WorldWideScience

Sample records for setting soil remediation

  1. Electrochemical remediation of copper contaminated clay soils

    Energy Technology Data Exchange (ETDEWEB)

    Korolev, V.A.; Babakina, O.A.; Mitojan, R.A. [Moscow State Univ. (Russian Federation)

    2001-07-01

    The study objective focused on electrochemical remediation copper polluted soils in the presence of adjuvant substances and conditions that are more effective for the treatment. Some of these substances were studied in different researches. Moreover, authors obtained a result of extraction copper rate higher than 90%. In this connection the following problems were set: - Influence organic and inorganic substances on copper mobility in soil under the DC current. - Moisture effect on copper migration in clay. - Electrochemical remediation soils different mineralogical composition. - A washing conditions contribution to electrochemical remediation of soil from copper. - Accuracy rating experimental dates. (orig.)

  2. Electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Karlsmose, Bodil; Ottosen, Lisbeth M.; Hansen, Lene

    1999-01-01

    The paper gives an overview of how heavy metals can be found in the soil and the theory of electrodialytic remediation. Basically electrodialytic remediation works by passing electric current through the soil, and the heavy metals in ionic form will carry some of the current. Ion-exchange membranes...... prevents the protons and the hydroxides ions from the electrode processes to enter the soil. The heavy metals are collected in a concentration compartment, which is separated from the soil by ion-exchange membranes. Examples from remediation experiments are shown, and it is demonstrated that it is possible...... to remediate soil polluted with heavy metals be this method. When adding desorbing agents or complexing agents, chosing the right current density, electrolyte and membranes, the proces can be optimised for a given remediation situation. Also electroosmosis is influencing the system, and if extra water...

  3. Thermal soil remediation

    International Nuclear Information System (INIS)

    Nelson, D.

    1999-01-01

    The environmental properties and business aspects of thermal soil remediation are described. Thermal soil remediation is considered as being the best option in cleaning contaminated soil for reuse. The thermal desorption process can remove hydrocarbons such as gasoline, kerosene and crude oil, from contaminated soil. Nelson Environmental Remediation (NER) Ltd. uses a mobile thermal desorption unit (TDU) with high temperature capabilities. NER has successfully applied the technology to target heavy end hydrocarbon removal from Alberta's gumbo clay in all seasons. The TDU consist of a feed system, a counter flow rotary drum kiln, a baghouse particulate removal system, and a secondary combustion chamber known as an afterburner. The technology has proven to be cost effective and more efficient than bioremediation and landfarming

  4. Electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Hansen, Lene

    1997-01-01

    It is not possible for all heavy metal polluted soils to remediate it by an applied electric field alone. A desorbing agent must in different cases be added to the soil in order to make the process possible or to make it cost effective......It is not possible for all heavy metal polluted soils to remediate it by an applied electric field alone. A desorbing agent must in different cases be added to the soil in order to make the process possible or to make it cost effective...

  5. Electrochemical remediation of the phenol contaminated clay soils

    Energy Technology Data Exchange (ETDEWEB)

    Korolev, V.A.; Babakina, O.A.; Lazareva, E.V. [Moscow State Univ. (Russian Federation)

    2001-07-01

    The study phenol migration induced by electric current is multiple analyze, because determine the governing factor of electrokinetic remediation is one more problem. The governing factor of phenol removal can be electroosmotic water transport, ionic migration or phenol destruction caused by electrolysis or oxidizing agents. Therefore research objective was study mechanism of removal phenol from soils with different mineral composition. To answer on set issue should be studied the effectiveness of electrochemcial remediation for contaminated soil and determination electrokinetic characteristics of interaction clay's particles with phenol solution. (orig.)

  6. Soil Contamination and Remediation Strategies. Current research and future challenge

    Science.gov (United States)

    Petruzzelli, G.

    2012-04-01

    Soil contamination: the heritage of industrial development Contamination is only a part of a whole set of soil degradation processes, but it is one of paramount importance since soil pollution greatly influences the quality of water, food and human health. Soil contamination has been identified as an important issue for action in the European strategy for soil protection, it has been estimated that 3.5 million of sites are potentially contaminated in Europe. Contaminated soils have been essentially discovered in industrial sites landfills and energy production plants, but accumulation of heavy metals and organic compounds can be found also in agricultural land . Remediation strategies. from incineration to bioremediation The assessment of soil contamination is followed by remedial action. The remediation of contaminated soils started using consolidates technologies (incineration inertization etc.) previously employed in waste treatment,. This has contributed to consider a contaminated soil as an hazardous waste. This rough approximation was unfortunately transferred in many legislations and on this basis soil knowledge have been used only marginally in the clean up procedures. For many years soil quality has been identified by a value of concentration of a contaminant and excavation and landfill disposal of soil has been largely used. In the last years the knowledge of remediation technology has rapidly grown, at present many treatment processes appear to be really feasible at field scale, and soil remediation is now based on risk assessment procedures. Innovative technologies, largely dependent on soil properties, such as in situ chemical oxidation, electroremediation, bioventing, soil vapor extraction etc. have been successfully applied. Hazardous organic compounds are commonly treated by biological technologies, biorememdiation and phytoremediation, being the last partially applied also for metals. Technologies selection is no longer exclusively based on

  7. [Immobilization remediation of Cd and Pb contaminated soil: remediation potential and soil environmental quality].

    Science.gov (United States)

    Sun, Yue-Bing; Wang, Peng-Chao; Xu, Ying-Ming; Sun, Yang; Qin, Xu; Zhao, Li-Jie; Wang, Lin; Liang, Xue-Feng

    2014-12-01

    A pot experiment was conducted to investigate the immobilization remediation effects of sepiolite on soils artificially combined contamination by Cd and Pb using a set of various pH and speciation of Cd and Pb in soil, heavy metal concentration in Oryza sativa L., and soil enzyme activity and microbial quantity. Results showed that the addition of sepiolite increased the soil pH, and the exchangeable fraction of heavy metals was converted into Fe-Mn oxide, organic and residual forms, the concentration of exchangeable form of Cd and Pb reduced by 1.4% - 72.9% and 11.8% - 51.4%, respectively, when compared with the control. The contents of heavy metals decreased with increasing sepiolite, with the maximal Cd reduction of 39.8%, 36.4%, 55.2% and 32.4%, respectively, and 22.1%, 54.6%, 43.5% and 17.8% for Pb, respectively, in the stems, leaves, brown rice and husk in contrast to CK. The addition of sepiolite could improve the soil environmental quality, the catalase and urease activities and the amount of bacteria and actinomycete were increased to some extents. Although the fungi number and invertase activity were inhibited compared with the control group, it was not significantly different (P > 0.05). The significant correlation between pH, available heavy metal content, urease and invertase activities and heavy metal concentration in the plants indicated that these parameters could be used to evaluate the effectiveness of stabilization remediation of heavy metal contaminated soil.

  8. Electrochemical soil remediation - accelerated soil weathering?

    Energy Technology Data Exchange (ETDEWEB)

    Ottosen, L.M.; Villumsen, A.; Hansen, H.K.; Jensen, P.E.; Pedersen, A.J. [Dept. of Civil Engineering, Technical Univ. of Denmark, Lyngby (Denmark); Ribeiro, A.B. [Dept. of Environmental Sciences and Engineering, New Univ. of Lisbon, Monte da Caparica (Portugal)

    2001-07-01

    In electrochemical soil remediation systems, where enhancement solutions and complexing agents are not used, a developing acidic front is mobilizing the heavy metals and the electric current is removing the mobilized elements from the soil. The hypotheses investigated in this paper is whether this process may be comparable to the chemical soil weathering that occurs in the environment due to the acidic rain, where the mobilized elements are removed from the soil by the penetrating water. Even through the weathering process is highly accelerated in the electrochemical cell. This paper shows results from electrodialytic remediation experiments performed with four different Danish heavy metal polluted soils. The main emphasis is laid on the relation between the developing acidic front and electromigration of Cu, Zn, Mn, Mg, Fe and Ca. (orig.)

  9. Operable Unit 3-13, Group 3, Other Surface Soils Remediation Sets 4-6 (Phase II) Waste Management Plan

    International Nuclear Information System (INIS)

    G. L. Schwendiman

    2006-01-01

    This Waste Management Plan describes waste management and waste minimization activities for Group 3, Other Surface Soils Remediation Sets 4-6 (Phase II) at the Idaho Nuclear Technology and Engineering Center located within the Idaho National Laboratory. The waste management activities described in this plan support the selected response action presented in the Final Record of Decision for Idaho Nuclear Technology and Engineering Center, Operable Unit 3-13. This plan identifies the waste streams that will be generated during implementation of the remedial action and presents plans for waste minimization, waste management strategies, and waste disposition

  10. Electrodialytic Remediation of Different Cu-Polluted Soils

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik K.; Hansen, Lene

    1999-01-01

    Based on characterization of a polluted soil a proper desorbing agent to be added to the soil before the remediation can be found. The desorbing agent can improve the remediation according to both energy consumption and duration of the action......Based on characterization of a polluted soil a proper desorbing agent to be added to the soil before the remediation can be found. The desorbing agent can improve the remediation according to both energy consumption and duration of the action...

  11. Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process.

    Science.gov (United States)

    Dias-Ferreira, Celia; Kirkelund, Gunvor M; Ottosen, Lisbeth M

    2015-01-01

    Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm(-2)), concentration of enhancing agent (0.25, 0.5 and 1.0 M) and remediation times (21, 42 and 117 d) for the removal of Cu and Cr from a calcareous soil. To gain insight on metal behavior, soil solution was periodically collected using suction cups. It was seen that current densities higher than 1.0 mA cm(-2) did not increase removal and thus using too high current densities can be a waste of energy. Desorption rate is important and both remediation time and ammonium citrate concentration are relevant parameters. It was possible to collect soil solution samples following an adaptation of the experimental set-up to ensure continuous supply of ammonium citrate to the soil in order to keep it saturated during the remediation. Monitoring soil solution gives valuable information on the evolution of remediation and helps deciding when the soil is remediated. Final concentrations in the soil ranged from 220 to 360 mg Cu kg(-1) (removals: 78-86%) and 440-590 mg Cr kg(-1) (removals: 35-51%), being within the 500 mg kg(-1) limit for a clean soil only for Cu. While further optimization is still required for Cr, the removal percentages are the highest achieved so far, for a real Cu and Cr-contaminated, calcareous soil. The results highlight EDR potential to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Remediation of soils combining soil vapor extraction and bioremediation: benzene.

    Science.gov (United States)

    Soares, António Alves; Albergaria, José Tomás; Domingues, Valentina Fernandes; Alvim-Ferraz, Maria da Conceição M; Delerue-Matos, Cristina

    2010-08-01

    This work reports the study of the combination of soil vapor extraction (SVE) with bioremediation (BR) to remediate soils contaminated with benzene. Soils contaminated with benzene with different water and natural organic matter contents were studied. The main goals were: (i) evaluate the performance of SVE regarding the remediation time and the process efficiency; (ii) study the combination of both technologies in order to identify the best option capable to achieve the legal clean up goals; and (iii) evaluate the influence of soil water content (SWC) and natural organic matter (NOM) on SVE and BR. The remediation experiments performed in soils contaminated with benzene allowed concluding that: (i) SVE presented (a) efficiencies above 92% for sandy soils and above 78% for humic soils; (b) and remediation times from 2 to 45 h, depending on the soil; (ii) BR showed to be an efficient technology to complement SVE; (iii) (a) SWC showed minimum impact on SVE when high airflow rates were used and led to higher remediation times for lower flow rates; (b) NOM as source of microorganisms and nutrients enhanced BR but hindered the SVE due the limitation on the mass transfer of benzene from the soil to the gas phase. (c) 2010 Elsevier Ltd. All rights reserved.

  13. Thermal remediation alters soil properties - a review.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Khan, Eakalak; Wick, Abbey F

    2018-01-15

    Contaminated soils pose a risk to human and ecological health, and thermal remediation is an efficient and reliable way to reduce soil contaminant concentration in a range of situations. A primary benefit of thermal treatment is the speed at which remediation can occur, allowing the return of treated soils to a desired land use as quickly as possible. However, this treatment also alters many soil properties that affect the capacity of the soil to function. While extensive research addresses contaminant reduction, the range and magnitude of effects to soil properties have not been explored. Understanding the effects of thermal remediation on soil properties is vital to successful reclamation, as drastic effects may preclude certain post-treatment land uses. This review highlights thermal remediation studies that have quantified alterations to soil properties, and it supplements that information with laboratory heating studies to further elucidate the effects of thermal treatment of soil. Notably, both heating temperature and heating time affect i) soil organic matter; ii) soil texture and mineralogy; iii) soil pH; iv) plant available nutrients and heavy metals; v) soil biological communities; and iv) the ability of the soil to sustain vegetation. Broadly, increasing either temperature or time results in greater contaminant reduction efficiency, but it also causes more severe impacts to soil characteristics. Thus, project managers must balance the need for contaminant reduction with the deterioration of soil function for each specific remediation project. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Steam and electroheating remediation of tight soils

    Energy Technology Data Exchange (ETDEWEB)

    Balshaw-Biddle, K.; Oubre, C.L.; Ward, C.H. [eds.; Dablow, J.F. III; Pearce, J.A.; Johnson, P.C.

    2000-07-01

    In the past few decades the need for soil remediation has become urgent, even more necessary--innovative, cost effective methods. Steam and Electroheating Remediation of Tight Soils presents the results of a field study testing the cleanup of semi-volatile fuels from tight soils using combination of hydraulic fracturing and soil heating technologies.

  15. Overview: Microbial amendment of remediated soils for effective recycling

    Directory of Open Access Journals (Sweden)

    Kim Soo-Bin

    2017-01-01

    Full Text Available In recent years, various methods are being considered with appropriate amendments, not with conventional reclamation to recycle deteriorated soils after remediation as agricultural addition, backfilling and construction materials etc. Among these amendments, microbial amendments with effective microorganism(EMs are known to improve soil qualities such as fertility, strength and toxicity to be recycled into possible utilizations. This study indicates the possibility of recycling the remediated soils by using these EMs most efficiently. Soil samples will be collected from contaminated sites with either heavy metals or petroleum and will be remediated by bench-scale soil washing and thermal desorption. And then the remediated soils will be treated with easily obtainable inocula, substrates (culture media near our life and they are compared with commercial EM products in terms of the cost and efficiency. Also, after treating with a number of mixing ratios, soil properties of (1 fresh, (2 contaminated, (3 remediated (4 amended soils will be evaluated based on soil quality indicators depending on demands and the optimal mixing ratios which are effective than commercial EM products will be determined. The ratio derived from pre-tests could be applied on the remediated soils with pilot-scale in order to assess suitability for recycling and characterize correlation between soil properties and microbial amendments regarding contaminants and remediation, and furthermore for modelling. In conclusion, application of the established models on recycling remediated soils may help to dispose the remediated soils in future, including environmental and ecological values as well as economical values.

  16. Electrodialytic remediation of heavy metal polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2012-01-01

    Electrodialytic soil remediation is a method for removal of heavy metals. Good results have previously been obtained with both treatment of a stationary, water saturated soil matrix and with remediation of a stirred suspension of soil in water. The two different setups have different uses....... The first as in-situ or on-site treatment when there is no requirement for fast remediation, as the removal rate of the heavy metals are dependent on the distance between the electrodes (everything else equal) and in such application the electrode spacing must have a certain distance (often meters......). In the stirred setup it is possible to shorten the transport route to few mm and to have a faster and continuous process. The present paper for the first time reports a direct comparison of the two options. The remediation of the stirred suspension showed faster than remediation of the water saturated soil even...

  17. Functioning of metal contaminated garden soil after remediation

    International Nuclear Information System (INIS)

    Jelusic, Masa; Grcman, Helena; Vodnik, Dominik; Suhadolc, Metka; Lestan, Domen

    2013-01-01

    The effect of remediation using three EDTA doses (10, 30, 60 mmol kg −1 ) on soil functioning was assessed using column experiment and Brassica rapa. Soil washing removed up to 77, 29 and 72% of metals from soil contaminated with 1378, 578 and 8.5 mg kg −1 of Pb, Zn and Cd, respectively. Sequential extraction indicated removal from the carbonate soil fraction. Metal oral-accessibility from the stomach phase was reduced by up to 75 and from the small intestine by up to 79% (Pb). Part of metals (up to 0.8% Cd) was lost due to leaching from columns. Remediation reduced toxic metal soil-root transfer by up to 61% but did not prevent metal accumulation in leaves. The fitness of plants grown on EDTA washed soils (gas exchange, fluorescence) was not compromised. Remediation initially reduced the soil DNA content (up to 29%, 30 mmol kg −1 EDTA) and changed the structure of microbial population. -- Highlights: ► Toxic metals contaminated garden soil was remediated in a pilot-scale. ► EDTA washing reduced soil Pb, Zn and Cd content and bioavailability. ► Remediated soil preserved the function of plant and microbial substrate. ► Remediation didn't prevent the accumulation of toxic metals in the test plant. -- EDTA soil washing effectively removed toxic metals and reduced their transfer from the soil to plant roots but did not prevent their accumulation in leaves

  18. An Expert support model for ex situ soil remediation

    NARCIS (Netherlands)

    Okx, J.P.; Frankhuizen, E.M.; Wit, de J.C.; Pijls, C.G.J.M.; Stein, A.

    2000-01-01

    This paper presents an expert support model recombining knowledge and experience obtained during ex situ soil remediation. To solve soil remediation problems, an inter-disciplinary approach is required. Responsibilities during the soil remediation process, however, are increasingly decentralised,

  19. Laboratory Experiment on Electrokinetic Remediation of Soil

    Science.gov (United States)

    Elsayed-Ali, Alya H.; Abdel-Fattah, Tarek; Elsayed-Ali, Hani E.

    2011-01-01

    Electrokinetic remediation is a method of decontaminating soil containing heavy metals and polar organic contaminants by passing a direct current through the soil. An undergraduate chemistry laboratory is described to demonstrate electrokinetic remediation of soil contaminated with copper. A 30 cm electrokinetic cell with an applied voltage of 30…

  20. Biological technologies for the remediation of co-contaminated soil.

    Science.gov (United States)

    Ye, Shujing; Zeng, Guangming; Wu, Haipeng; Zhang, Chang; Dai, Juan; Liang, Jie; Yu, Jiangfang; Ren, Xiaoya; Yi, Huan; Cheng, Min; Zhang, Chen

    2017-12-01

    Compound contamination in soil, caused by unreasonable waste disposal, has attracted increasing attention on a global scale, particularly since multiple heavy metals and/or organic pollutants are entering natural ecosystem through human activities, causing an enormous threat. The remediation of co-contaminated soil is more complicated and difficult than that of single contamination, due to the disparate remediation pathways utilized for different types of pollutants. Several modern remediation technologies have been developed for the treatment of co-contaminated soil. Biological remediation technologies, as the eco-friendly methods, have received widespread concern due to soil improvement besides remediation. This review summarizes the application of biological technologies, which contains microbial technologies (function microbial remediation and composting or compost addition), biochar, phytoremediation technologies, genetic engineering technologies and biochemical technologies, for the remediation of co-contaminated soil with heavy metals and organic pollutants. Mechanisms of these technologies and their remediation efficiencies are also reviewed. Based on this study, this review also identifies the future research required in this field.

  1. Quicklime-induced changes of soil properties: Implications for enhanced remediation of volatile chlorinated hydrocarbon contaminated soils via mechanical soil aeration.

    Science.gov (United States)

    Ma, Yan; Dong, Binbin; He, Xiaosong; Shi, Yi; Xu, Mingyue; He, Xuwen; Du, Xiaoming; Li, Fasheng

    2017-04-01

    Mechanical soil aeration is used for soil remediation at sites contaminated by volatile organic compounds. However, the effectiveness of the method is limited by low soil temperature, high soil moisture, and high soil viscosity. Combined with mechanical soil aeration, quicklime has a practical application value related to reinforcement remediation and to its action in the remediation of soil contaminated with volatile organic compounds. In this study, the target pollutant was trichloroethylene, which is a volatile chlorinated hydrocarbon pollutant commonly found in contaminated soils. A restoration experiment was carried out, using a set of mechanical soil-aeration simulation tests, by adding quicklime (mass ratios of 3, 10, and 20%) to the contaminated soil. The results clearly indicate that quicklime changed the physical properties of the soil, which affected the environmental behaviour of trichloroethylene in the soil. The addition of CaO increased soil temperature and reduced soil moisture to improve the mass transfer of trichloroethylene. In addition, it improved the macroporous cumulative pore volume and average pore size, which increased soil permeability. As soil pH increased, the clay mineral content in the soils decreased, the cation exchange capacity and the redox potential decreased, and the removal of trichloroethylene from the soil was enhanced to a certain extent. After the addition of quicklime, the functional group COO of soil organic matter could interact with calcium ions, which increased soil polarity and promoted the removal of trichloroethylene. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Electrokinetic remediation of fluorine-contaminated soil and its impact on soil fertility.

    Science.gov (United States)

    Zhou, Ming; Wang, Hui; Zhu, Shufa; Liu, Yana; Xu, Jingming

    2015-11-01

    Compared to soil pollution by heavy metals and organic pollutants, soil pollution by fluorides is usually ignored in China. Actually, fluorine-contaminated soil has an unfavorable influence on human, animals, plants, and surrounding environment. This study reports on electrokinetic remediation of fluorine-contaminated soil and the effects of this remediation technology on soil fertility. Experimental results showed that electrokinetic remediation using NaOH as the anolyte was a considerable choice to eliminate fluorine in contaminated soils. Under the experimental conditions, the removal efficiency of fluorine by the electrokinetic remediation method was 70.35%. However, the electrokinetic remediation had a significant impact on the distribution and concentrations of soil native compounds. After the electrokinetic experiment, in the treated soil, the average value of available nitrogen was raised from 69.53 to 74.23 mg/kg, the average value of available phosphorus and potassium were reduced from 20.05 to 10.39 mg/kg and from 61.31 to 51.58 mg/kg, respectively. Meanwhile, the contents of soil available nitrogen and phosphorus in the anode regions were higher than those in the cathode regions, but the distribution of soil available potassium was just the opposite. In soil organic matter, there was no significant change. These experiment results suggested that some steps should be taken to offset the impacts, after electrokinetic treatment.

  3. Advanced multivariate analysis to assess remediation of hydrocarbons in soils.

    Science.gov (United States)

    Lin, Deborah S; Taylor, Peter; Tibbett, Mark

    2014-10-01

    Accurate monitoring of degradation levels in soils is essential in order to understand and achieve complete degradation of petroleum hydrocarbons in contaminated soils. We aimed to develop the use of multivariate methods for the monitoring of biodegradation of diesel in soils and to determine if diesel contaminated soils could be remediated to a chemical composition similar to that of an uncontaminated soil. An incubation experiment was set up with three contrasting soil types. Each soil was exposed to diesel at varying stages of degradation and then analysed for key hydrocarbons throughout 161 days of incubation. Hydrocarbon distributions were analysed by Principal Coordinate Analysis and similar samples grouped by cluster analysis. Variation and differences between samples were determined using permutational multivariate analysis of variance. It was found that all soils followed trajectories approaching the chemical composition of the unpolluted soil. Some contaminated soils were no longer significantly different to that of uncontaminated soil after 161 days of incubation. The use of cluster analysis allows the assignment of a percentage chemical similarity of a diesel contaminated soil to an uncontaminated soil sample. This will aid in the monitoring of hydrocarbon contaminated sites and the establishment of potential endpoints for successful remediation.

  4. Remediation of a radioactively contaminated soil using a mobile soil-washing system

    International Nuclear Information System (INIS)

    Grant, D.C.; Lahoda, E.J.; Dietrich, A.J.; Weigle, D.H.; Keegan, C.P.; Sachse, J.D.

    1993-01-01

    In order to obtain free-release of a former uranium mining site in Texas, it was required that the surface soil meet specific radiological guidelines. The soil has been contaminated with uranium and radium as a result of the spillage of well-drilling material, process solutions, and ion exchange resins during mining. To meet the required guidelines, the contaminated soil had to be either removed and disposed of off-site or remediated. For economic and long-term liability reasons, remediation of the soil by soil washing was performed. The remediation of this site utilizing the Scientific Ecology Group's soil washing system is discussed in this paper

  5. Remediation of sandy soils contaminated with hydrocarbons and halogenated hydrocarbons by soil vapour extraction.

    Science.gov (United States)

    Albergaria, José Tomás; Alvim-Ferraz, Maria da Conceição M; Delerue-Matos, Cristina

    2012-08-15

    This paper presents the study of the remediation of sandy soils containing six of the most common contaminants (benzene, toluene, ethylbenzene, xylene, trichloroethylene and perchloroethylene) using soil vapour extraction (SVE). The influence of soil water content on the process efficiency was evaluated considering the soil type and the contaminant. For artificially contaminated soils with negligible clay contents and natural organic matter it was concluded that: (i) all the remediation processes presented efficiencies above 92%; (ii) an increase of the soil water content led to a more time-consuming remediation; (iii) longer remediation periods were observed for contaminants with lower vapour pressures and lower water solubilities due to mass transfer limitations. Based on these results an easy and relatively fast procedure was developed for the prediction of the remediation times of real soils; 83% of the remediation times were predicted with relative deviations below 14%. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Electrodialytic remediation of soil polluted with heavy metals

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Hansen, Lene

    1999-01-01

    In this paper, the importance of some parameters for the efficiency of electrodialytic soil remediation are evaluated. The parameters investigated are pH, the limiting current density and the adding of desorbing agents to the soil. Three parameters are found to be of greatest importance. Results...... show that the electrodialytic soil remediation can be optimized by understanding and adjusting of these parameters. For scaling up of the remediation method these parameters are of crucial importance....

  7. Soil remediation process and system

    International Nuclear Information System (INIS)

    Monlux, K.J.

    1992-01-01

    This patent describes a process for remediation of soil containing up to about 30,000 ppm hydrocarbon contaminants. It comprises: providing hydrocarbon-contaminated soil in a divided condition of minus 1 1/2 double-prime to a first confined zone where it is exposed to an open flame; heating while agitating the contaminated soil in an oxidizing atmosphere in the first zone to a temperature below soil ignition within a range of from about 375 degrees F. to about 750 degrees F. for a time sufficient to drive off as vapors a substantial percentage of the hydrocarbon contaminates from the soil; passing hot gases containing the hydrocarbon contaminates from the soil; passing hot gases containing the hydrocarbon vapors from the first zone to a second zone; recovering heat from the hot gases in the second zone to condense a substantial percentage of the hydrocarbon vapors as liquid hydrocarbons; recovering the liquid hydrocarbons; and removing the soil from the first zone as remediated soil having below about 1000 ppm hydrocarbon contaminants

  8. Electrodialytic Remediation of Pb Contaminated Soil - Effects of Soil Properties and Pb Distribution

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Jensen, Pernille Erland

    1999-01-01

    The aim of this work was to investigate the effects of soil properties and Pb distribution on the electrodialytic remediation of Pb contaminated soil. Two naturally Pb contaminated soils were compared with respect to total Pb content, Pb distribution, pH, carbonate content, clay content and organic...... matter, and an electrodialytic remediation experiment was made on each soil.It was concluded that soil pH was the most important factor limiting the mobilisation of Pb. In one of the remediation experiments it was possible to mobilise and reduce the amount of Pb significantly, whereas in the other only...... a small amount of the initial Pb was mobilised at similar experimental conditions. A high buffering capacity of one of the soils, which was partly due to a high carbonate content, led to a bad remediation result....

  9. Microbial Remediation of Metals in Soils

    Science.gov (United States)

    Hietala, K. A.; Roane, T. M.

    Of metal-contaminated systems, metal-contaminated soils present the greatest challenge to remediation efforts because of the structural, physical, chemical, and biological heterogeneities encountered in soils. One of the confounding issues surrounding metal remediation is that metals can be readily re-mobilized, requiring constant monitoring of metal toxicity in sites where metals are not removed. Excessive metal content in soils can impact air, surface water, and groundwater quality. However, our understanding of how metals affect organisms, from bacteria to plants and animals, and our ability to negate the toxicity of metals are in their infancies. The ubiquity of metal contamination in developing and industrialized areas of the world make remediation of soils via removal, containment, and/or detoxification of metals a primary concern. Recent examples of the health and environmental consequences of metal contamination include arsenic in drinking water (Wang and Wai 2004), mercury levels in fish (Jewett and Duffy 2007), and metal uptake by agricultural crops (Howe et al. 2005). The goal of this chapter is to summarize the traditional approaches and recent developments using microorganisms and microbial products to address metal toxicity and remediation.

  10. Electrodialytic Remediation of Different Heavy Metal-Polluted Soils in Suspension

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2013-01-01

    Electrokinetic remediation of heavy metal-polluted soil faces different challenges in relation to implementation. One challenge is to cope with the nonlinear and transient geochemical changes in the soil and another is to increase the remediation rate. Both these challenges are met when treating...... the soil in a suspension in an electrodialytic cell. The soil suspension is stirred and uniform during treatment. Previously, it has been shown that a faster remediation can be obtained when remediating a stirred soil suspension compared to a stationary water saturated soil (all other parameters the same...

  11. Remediation techniques for heavy metal-contaminated soils: Principles and applicability.

    Science.gov (United States)

    Liu, Lianwen; Li, Wei; Song, Weiping; Guo, Mingxin

    2018-08-15

    Globally there are over 20millionha of land contaminated by the heavy metal(loid)s As, Cd, Cr, Hg, Pb, Co, Cu, Ni, Zn, and Se, with the present soil concentrations higher than the geo-baseline or regulatory levels. In-situ and ex-situ remediation techniques have been developed to rectify the heavy metal-contaminated sites, including surface capping, encapsulation, landfilling, soil flushing, soil washing, electrokinetic extraction, stabilization, solidification, vitrification, phytoremediation, and bioremediation. These remediation techniques employ containment, extraction/removal, and immobilization mechanisms to reduce the contamination effects through physical, chemical, biological, electrical, and thermal remedy processes. These techniques demonstrate specific advantages, disadvantages, and applicability. In general, in-situ soil remediation is more cost-effective than ex-situ treatment, and contaminant removal/extraction is more favorable than immobilization and containment. Among the available soil remediation techniques, electrokinetic extraction, chemical stabilization, and phytoremediation are at the development stage, while the others have been practiced at full, field scales. Comprehensive assessment indicates that chemical stabilization serves as a temporary soil remediation technique, phytoremediation needs improvement in efficiency, surface capping and landfilling are applicable to small, serious-contamination sites, while solidification and vitrification are the last remediation option. The cost and duration of soil remediation are technique-dependent and site-specific, up to $500ton -1 soil (or $1500m -3 soil or $100m -2 land) and 15years. Treatability studies are crucial to selecting feasible techniques for a soil remediation project, with considerations of the type and degree of contamination, remediation goals, site characteristics, cost effectiveness, implementation time, and public acceptability. Copyright © 2018 Elsevier B.V. All rights

  12. Soil sorting, new approach to site remediation management

    International Nuclear Information System (INIS)

    Bramlitt, E.T.; Woods, J.A.; Dillon, M.J.

    1996-01-01

    Soil sorting is the technology which conveys soil beneath contaminant detectors and, based on contaminant signal, automatically toggles a gate at the conveyor end to send soil with contamination above a guideline to a separate location from soil which meets the guideline. The technology was perfected for remediation of sites having soils with radioactive contamination, but it is applicable to other contaminants when instrumental methods exist for rapid contaminant detection at levels of concern. This paper examines the three methods for quantifying contamination in soil in support of site remediation management. Examples are discussed where the primary contaminant is plutonium, a radioactive substance and source of nuclear energy which can be hazardous to health when in the environment without controls. Field survey instruments are very sensitive to plutonium and can detect it in soil at levels below a part per billion, and there are a variety of soils which have been contaminated by plutonium and thoroughly investigated. The lessons learned with plutonium are applicable to other types of contaminants and site remediations. The paper concludes that soil sorting can be the most cost effective approach to site remediation, and it leads to the best overall cleanup

  13. Electrodialytic remediation of suspended soil – Comparison of two different soil fractions

    DEFF Research Database (Denmark)

    Sun, Tian Ran; Ottosen, Lisbeth M.; Jensen, Pernille Erland

    2012-01-01

    Electrodialytic remediation (EDR) can be used for removal of heavy metals from suspended soil, which allows for the soil remediation to be a continuous process. The present paper focused on the processing parameters for remediation of a soil polluted with Cu and As from wood preservation. Six...... electrodialytic treatments lasting from 5 to 22 days with different liquid to solid ratio (L/S) and current intensity were conducted. Among treatments, the highest removal was obtained from the soil fines with 5mA current at L/S 3.5 after 22 days where 96% of Cu and 64% of As were removed. Comparing the removal...... from the original soil and the soil fines in experiments with identical charge transportation, higher removal efficiency was observed from the soil fines. Constant current with 5mA could be maintained at L/S 3.5 for the soil fines while not for the original soil. Doubling current to 10mA could...

  14. Some aspects of remediation of contaminated soils

    Science.gov (United States)

    Bech, Jaume; Korobova, Elena; Abreu, Manuela; Bini, Claudio; Chon, Hyo-Taek; Pérez-Sirvent, Carmen; Roca, Núria

    2014-05-01

    Soils are essential components of the environment, a limited precious and fragile resource, the quality of which should be preserved. The concentration, chemical form and distribution of potential harmful elements in soils depends on parent rocks, weathering, soil type and soil use. However, their concentration can be altered by mismanagement of industrial and mining activities, energy generation, traffic increase, overuse of agrochemicals, sewage sludge and waste disposal, causing contamination, environmental problems and health concerns. Heavy metals, some metalloids and radionuclides are persistent in the environment. This persistence hampers the cost/efficiency of remediation technologies. The choice of the most appropriate soil remediation techniques depends of many factors and essentially of the specific site. This contribution aims to offer an overview of the main remediation methods in contaminated soils. There are two main groups of technologies: the first group dealing with containment and confinement, minimizing their toxicity, mobility and bioavailability. Containment measures include covering, sealing, encapsulation and immobilization and stabilization. The second group, remediation with decontamination, is based on the remotion, clean up and/or destruction of contaminants. This group includes mechanical procedures, physical separations, chemical technologies such as soil washing with leaching or precipitation of harmful elements, soil flushing, thermal treatments and electrokinetic technologies. There are also two approaches of biological nature: bioremediation and phytoremediation. Case studies from Chile, Ecuador, Italy, Korea, Peru, Portugal, Russia and Spain, will be discussed in accordance with the time available.

  15. Ecotoxicological impact of two soil remediation treatments in Lactuca sativa seeds.

    Science.gov (United States)

    Rede, Diana; Santos, Lúcia H M L M; Ramos, Sandra; Oliva-Teles, Filipe; Antão, Cristina; Sousa, Susana R; Delerue-Matos, Cristina

    2016-09-01

    Pharmaceuticals have been identified as environmental emerging pollutants and are present in different compartments, including soils. Chemical remediation showed to be a good and suitable approach for soil remediation, though the knowledge in their impact for terrestrial organisms is still limited. Therefore, in this work, two different chemical remediation treatments (Fenton oxidation and nanoremediation) were applied to a soil contaminated with an environmental representative concentration of ibuprofen (3 ng g(-1)). The phytotoxic impact of a traditional soil remediation treatment (Fenton oxidation) and of a new and more sustainable approach for soil remediation (nanoremediation using green nano-scale zero-valent iron nanoparticles (nZVIs)) was evaluated in Lactuca sativa seeds. Percentage of seed germination, root elongation, shoot length and leaf length were considered as endpoints to assess the possible acute phytotoxicity of the soil remediation treatments as well as of the ibuprofen contaminated soil. Both chemical remediation treatments showed to have a negative impact in the germination and development of lettuce seeds, exhibiting a reduction up to 45% in the percentage of seed germination and a decrease around 80% in root elongation comparatively to the contaminated soil. These results indicate that chemical soil remediation treatments could be more prejudicial for terrestrial organisms than contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. The risk implications of approaches to setting soil remediation goals at hazardous waste contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Labieniec, Paula Ann [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    1994-08-01

    An integrated exposure and carcinogenic risk assessment model for organic contamination in soil, SoilRisk, was developed and used for evaluating the risk implications of both site-specific and uniform-concentration approaches to setting soil remediation goals at hazardous-waste-contaminated sites. SoilRisk was applied to evaluate the uncertainty in the risk estimate due to uncertainty in site conditions at a representative site. It was also used to evaluate the variability in risk across a region of sites that can occur due to differences in site characteristics that affect contaminant transport and fate when a uniform concentration approach is used. In evaluating regional variability, Ross County, Ohio and the State of Ohio were used as examples. All analyses performed considered four contaminants (benzene, trichloroethylene (TCE), chlordane, and benzo[a]pyrene (BAP)) and four exposure scenarios (commercial, recreational and on- and offsite residential). Regardless of whether uncertainty in risk at a single site or variability in risk across sites was evaluated, the exposure scenario specified and the properties of the target contaminant had more influence than variance in site parameters on the resulting variance and magnitude of the risk estimate. In general, variance in risk was found to be greater for the relatively less degradable and more mobile of the chemicals studied (TCE and chlordane) than for benzene which is highly degradable and BAP which is very immobile in the subsurface.

  17. The risk implications of approaches to setting soil remediation goals at hazardous waste contaminated sites

    International Nuclear Information System (INIS)

    Labieniec, P.A.

    1994-08-01

    An integrated exposure and carcinogenic risk assessment model for organic contamination in soil, SoilRisk, was developed and used for evaluating the risk implications of both site-specific and uniform-concentration approaches to setting soil remediation goals at hazardous-waste-contaminated sites. SoilRisk was applied to evaluate the uncertainty in the risk estimate due to uncertainty in site conditions at a representative site. It was also used to evaluate the variability in risk across a region of sites that can occur due to differences in site characteristics that affect contaminant transport and fate when a uniform concentration approach is used. In evaluating regional variability, Ross County, Ohio and the State of Ohio were used as examples. All analyses performed considered four contaminants (benzene, trichloroethylene (TCE), chlordane, and benzo[a]pyrene (BAP)) and four exposure scenarios (commercial, recreational and on- and offsite residential). Regardless of whether uncertainty in risk at a single site or variability in risk across sites was evaluated, the exposure scenario specified and the properties of the target contaminant had more influence than variance in site parameters on the resulting variance and magnitude of the risk estimate. In general, variance in risk was found to be greater for the relatively less degradable and more mobile of the chemicals studied (TCE and chlordane) than for benzene which is highly degradable and BAP which is very immobile in the subsurface

  18. Enhanced electrokinetic remediation of fluorine-contaminated soil by applying an ammonia continuous circulation system

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Shufa; Zhou, Ming; Zhang, Shuangyan [Henan University of Science and Technology, Luoyang (China)

    2016-02-15

    The objective of this research was to investigate the effects of ammonia continuous circulation enhanced electrokinetic remediation of fluorine contaminated soil and to analyze its influence on soil pH after remediation. An experimental study was carried out in self-made electrokinetic apparatus. The voltage gradient was set at 1.0V/cm and ammonia water with different concentrations was used as electrolyte which circulated in series. Comparative studies were made by using deionized water as electrolyte which circulated separately in one experiment and continuously in another. According to the experiment the continuous circulation of ammonia water increased the current value during the remediation process and maintained current through the soil cell stabler, which not only increased fluorine migration but also reduced energy consumption. Among the given ammonia concentrations (0, 0.01, 0.1 and 0.2mol/L) the removal rate increased with ammonia concentration. 0.2mol/L had the highest current (26.8mA), and the removal rate amounted up to 57.3%. By using ammonia circulation enhanced electrokinetic technology, the difference between pH values of cathode soil and anode soil became smaller. Ammonia continuous circulation enhanced electrokinetics can effectively remediate fluorine contaminated soil and the residual ammonia in the soil can also improve soil fertility.

  19. Lasagna trademark soil remediation

    International Nuclear Information System (INIS)

    1996-04-01

    Lasagna trademark is an integrated, in situ remediation technology being developed which remediates soils and soil pore water contaminated with soluble organic compounds. Lasagna trademark is especially suited to sites with low permeability soils where electroosmosis can move water faster and more uniformly than hydraulic methods, with very low power consumption. The process uses electrokinetics to move contaminants in soil pore water into treatment zones where the contaminants can be captured and decomposed. Initial focus is on trichloroethylene (TCE), a major contaminant at many DOE and industrial sites. Both vertical and horizontal configurations have been conceptualized, but fieldwork to date is more advanced for the vertical configuration. Major features of the technology are electrodes energized by direct current, which causes water and soluble contaminants to move into or through the treatment layers and also heats the soil; treatment zones containing reagents that decompose the soluble organic contaminants or adsorb contaminants for immobilization or subsequent removal and disposal; and a water management system that recycles the water that accumulates at the cathode (high pH) back to the anode (low pH) for acid-base neutralization. Alternatively, electrode polarity can be reversed periodically to reverse electroosmotic flow and neutralize pH

  20. Remediation of lead contaminated soil by biochar-supported nano-hydroxyapatite.

    Science.gov (United States)

    Yang, Zhangmei; Fang, Zhanqiang; Zheng, Liuchun; Cheng, Wen; Tsang, Pokeung Eric; Fang, Jianzhang; Zhao, Dongye

    2016-10-01

    In this study, a high efficiency and low cost biochar-supported nano-hydroxyapatite (nHAP@BC) material was used in the remediation of lead (Pb)-contaminated soil. The remediation effect of nHAP@BC on Pb-contaminated soil was evaluated through batch experiments. The stability, bioaccessibility of Pb in the soil and the change in soil characteristics are discussed. Furthermore, the effects of the amendments on the growth of cabbage mustard seedlings and the accumulation of Pb were studied. The results showed that the immobilization rates of Pb in the soil were 71.9% and 56.8%, respectively, after a 28 day remediation using 8% nHAP and nHAP@BC materials, and the unit immobilization amount of nHAP@BC was 5.6 times that of nHAP, indicating that nHAP@BC can greatly reduce the cost of remediation of Pb in soil. After the nHAP@BC remediation, the residual fraction Pb increased by 61.4%, which greatly reduced the bioaccessibility of Pb in the soil. Moreover, nHAP@BC could effectively reduce the accumulation of Pb in plants by 31.4%. Overall, nHAP@BC can effectively remediate Pb-contaminated soil and accelerate the recovery of soil fertility. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Remediation of Soil at Nuclear Sites

    International Nuclear Information System (INIS)

    Holmes, R.; Boardman, C.; Robbins, R; Fox, Robert Vincent; Mincher, Bruce Jay

    2000-01-01

    As the major nuclear waste and decontamination and decommissioning projects progress, one of the remaining problems that faces the nuclear industry is that of site remediation. The range of contamination levels and contaminants is wide and varied and there is likely to be a significant volume of soil contaminated with transuranics and hazardous organic materials that could qualify as mixed TRU waste. There are many technologies that offer the potential for remediating this waste but few that tackle all or most of the contaminants and even fewer that have been deployed with confidence. This paper outlines the progress made in proving the ability of Supercritical Fluid Extraction as a method of remediating soil, classified as mixed (TRU) transuranic waste

  2. Use of surfactants for the remediation of contaminated soils: A review

    International Nuclear Information System (INIS)

    Mao, Xuhui; Jiang, Rui; Xiao, Wei; Yu, Jiaguo

    2015-01-01

    Highlights: • The recent advances in use of surfactant for soil remediation are reviewed. • The mechanisms of surfactant-based soil remediation are discussed. • A review on the application of different types of surfactants is made. • The future research direction of surfactant-based technologies is suggested. - Abstract: Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation

  3. Use of surfactants for the remediation of contaminated soils: A review

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Xuhui, E-mail: clab@whu.edu.cn [School of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Jiang, Rui; Xiao, Wei [School of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Yu, Jiaguo, E-mail: jiaguoyu@yahoo.com [State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China)

    2015-03-21

    Highlights: • The recent advances in use of surfactant for soil remediation are reviewed. • The mechanisms of surfactant-based soil remediation are discussed. • A review on the application of different types of surfactants is made. • The future research direction of surfactant-based technologies is suggested. - Abstract: Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation.

  4. Remediation trials of crude oil contaminated soil using different ...

    African Journals Online (AJOL)

    A 3 month remediation trial of the use of detergent and sawdust in different combination forms in the restoration of a crude oil contaminated tropical soil was investigated. 8 remediation treatments labeled A – H in addition to the control (I) were used in 10 kg soil artificially polluted with 300 ml crude oil each. Remediation ...

  5. Soil radiological characterisation and remediation at CIEMAT

    International Nuclear Information System (INIS)

    Correa, Cristina; Garcia Tapias, Esther; Leganes, Jose

    2012-01-01

    Located in Madrid, CIEMAT is the Spanish Centre for Energy-Related, Environmental and Technological Research. It used to have more than 60 facilities in operation that allowed a wide range of activities in the nuclear field and in the application of ionising radiations. At present, the centre includes several facilities; some of them are now obsolete, shut down and in dismantling phases. In 2000 CIEMAT started the 'Integrated plan for the improvement of CIEMAT facilities (PIMIC)', which includes activities for the decontamination, dismantling, rehabilitation of obsolete installations and soil remediation activities. A small contaminated area named with the Spanish word 'Lenteja' (Lentil), has had to be remediate and restored. In the 70's, an incidental leakage of radioactive liquid occurred during a transference operation from the Reprocessing Plant to the Liquid Treatment Installation, and contaminated about 1000 m 3 of soil. Remediation activities in this area started with an exhaustive radiological characterisation of the soil, including surface samples and up to 16 meters boreholes, and the development of a comprehensive radiological characterization methodology for pre-classification of materials. Once the framework was defined the following tasks were being carried out: preparation of the area, soil extraction activities and final radiological characterisation for release purposes. Next step will be the refilling of the resulting hole from the removal soil activities. This paper will describe the soil radiological characterization and remediation activities at the Lentil Zone in Ciemat Research Centre. (authors)

  6. 200 Areas soil remediation strategy -- Environmental Restoration Program

    International Nuclear Information System (INIS)

    1996-09-01

    The remediation and waste management activities in the 200 Areas of the Hanford Site (located in Richland, Washington) currently range from remediating groundwater, remediating source units (contaminated soils), decontaminating and decommissioning of buildings and structures, maintaining facilities, managing transuranic, low-level and mixed waste, and operating tank farms that store high-level waste. This strategy focuses on the assessment and remediation of soil that resulted from the discharge of liquids and solids from processing facilities to the ground (e.g., ponds, ditches, cribs, burial grounds) in the 200 Areas and addresses only those waste sites assigned to the Environmental Restoration Program

  7. evaluation of different remediation methods of polluted soils using nuclear technique

    International Nuclear Information System (INIS)

    Moussa, I.E.A.

    2012-01-01

    Remediation of heavy metal contaminated has become a considerable task to introduce such marginal or waste lands into productive systems. Various techniques, i.e. chemical and organic agents, bio- and Phyto remediation including microorganisms and/or phyto plants are used to remediate such contaminated soils. The contamination of the soil with metals has become a widespread environmental problem in many industrialized countries. The fact that the Earth's surface is becoming increasingly polluted by human activities challenges society to develop strategies for sustainability that conserve nonrenewable natural resources such as soil. The aim of the present study is to investigate the effectiveness of (I) some chemical and organic amendments in remediation of heavy metals contaminated soil. At the same time, a follow up the effects of interaction between amendment concentration and incubation time intervals on bioavailability of tested heavy metals was taken into consideration. (II) Fungi inoculation in remediation of heavy metals contaminated soils. (III) Calcium carbonate on the potentiality of panikum and sudan grass (as hyper accumulators) in remediation of heavy metals contaminated soil. To fulfill this task, it was suggested to conduct three experiments, namely; (1) Chemical remediation of Contaminated Soils experiment (2) Bioremediation experiment (3) Phyto remediation Experiment

  8. Remediation of PAH-contaminated soil using Achromobacter sp

    International Nuclear Information System (INIS)

    Cutright, T.J.; Lee, S.

    1994-01-01

    Several technologies have the potential to effectively remediate soil contaminated with polycyclic aromatic hydrocarbons (PAHs): solvent extraction, coal-oil agloflotation, supercritical extraction, and bioremediation. Due to the cost effectiveness and in-situ treatment capabilities of bioremediation, studies were conducted to determine the efficiency of Achromobacter sp. to remediate an industrial contaminated soil sample. Specifically, the use of three different mineral salt solutions in conjunction with the Achromobacter sp. was investigated. The molecular identification of the contaminants and their respective levels after remediation were determined using a Hewlett-Packard 1050 HPLC. Preliminary results show a 92% remediation for the use of two of the mineral salt solutions after 20 days' treatment. After 8 weeks, the remediation efficiency reached 99%. Bioremediation was also critically compared to the other potential remediation technologies

  9. Phyto remediation of PAH contaminated soil

    International Nuclear Information System (INIS)

    Petruzzelli, G.; Pedron, F.; Barbafieri, M.; Cervelli, St.; Vigna Guidi, G.

    2005-01-01

    Phyto-remediation may enhance degradation of organic compounds promoting an adequate substrate for microbial growth. The aim of this work was to evaluate the efficiency of two plant species, Lupinus albus and Zea mais, in the bio-remediation of a PAH contaminated soil. This soil has been collected in a contaminated industrial area in Italy characterized by PAH concentrations up to 16000 mg/Kg. Microcosms experiments were carried out by planting Lupinus albus and Zea mais in the polluted soil; controls without plants were run separately. Growing period lasted by three months. Plants favoured PAH biodegradation by percentages of 32% with Lupinus albus and 22% with Zea mais, with respect to non vegetated microcosms. (authors)

  10. Pulse current enhanced electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Sun, Tian R.; Ottosen, Lisbeth M.; Jensen, Pernille E.

    2012-01-01

    Energy consumption is an important factor influencing the cost of electrodialytic soil remediation (EDR). It has been indicated that the pulse current (in low frequency range) could decrease the energy consumption during EDR. This work is focused on the comparison of energy saving effect at diffe......Energy consumption is an important factor influencing the cost of electrodialytic soil remediation (EDR). It has been indicated that the pulse current (in low frequency range) could decrease the energy consumption during EDR. This work is focused on the comparison of energy saving effect...

  11. The soil remediation fund for petrol stations in Belgium

    International Nuclear Information System (INIS)

    Naeyer, F. de; Van Dyck, E.; Janssens, J.P.; Duliere, A.; Fondaire, D.; Bodart, O.

    2005-01-01

    In the Flemish, Brussels-Capital and Walloon Region, petrol stations are subjected to strict operating standards, to avoid soil contamination as much as possible in the future. Besides these operating requirements, regional authorities also issued regulations regarding the remediation of contaminated soils. For many petrol stations operators, land owners and users, these rules and regulations are a heavy financial burden. As a result, the soil contamination threaten to become a public charge, due to a lack of adequate remediation by the stakeholders. After years of negotiating between the petroleum industry and the government the negotiations finally resulted in a cooperation agreement between the Federal Government, the Flemish, Walloon and Brussels-Capital Regions regarding the execution and financing of the remediation of contaminated soil at petrol stations. The cooperation agreement, signed in Brussels on 13 December 2002 and approved by all Regions and the Federal Government, makes it possible to provide a structured approach for the remediation of the soil contamination at petrol stations in Belgium. In the cooperation agreement the establishment of an Inter-regional Soil Remediation Committee is provided to guarantee the fund's independence and to observe the fund's operation. The official start is given through the accreditation of BOFAS by the Inter-regional Soil Remediation Committee. To calculate the amount that would be necessary for the remediation of the soil contamination at petrol stations and the contribution to the fund, an economical research has been carried out. This research indicated that the total cost for the remediation of the soil contamination at petrol stations in Belgium is situated between 400 and 450 million EUR. BOFAS has calculated that 5.000 petrol stations can comply with the conditions mentioned in the cooperation agreement. Operators, Owners or Actual users can submit an application if they comply with the legally established

  12. The soil remediation fund for petrol stations in Belgium

    Energy Technology Data Exchange (ETDEWEB)

    Naeyer, F. de; Van Dyck, E. [OVAM, Mechelen (Belgium); Janssens, J.P.; Duliere, A. [BIM, Brussel (Belgium); Fondaire, D. [DGRNE, Liege (Belgium); Bodart, O. [Governement Wallon, Namur (Belgium)

    2005-07-01

    In the Flemish, Brussels-Capital and Walloon Region, petrol stations are subjected to strict operating standards, to avoid soil contamination as much as possible in the future. Besides these operating requirements, regional authorities also issued regulations regarding the remediation of contaminated soils. For many petrol stations operators, land owners and users, these rules and regulations are a heavy financial burden. As a result, the soil contamination threaten to become a public charge, due to a lack of adequate remediation by the stakeholders. After years of negotiating between the petroleum industry and the government the negotiations finally resulted in a cooperation agreement between the Federal Government, the Flemish, Walloon and Brussels-Capital Regions regarding the execution and financing of the remediation of contaminated soil at petrol stations. The cooperation agreement, signed in Brussels on 13 December 2002 and approved by all Regions and the Federal Government, makes it possible to provide a structured approach for the remediation of the soil contamination at petrol stations in Belgium. In the cooperation agreement the establishment of an Inter-regional Soil Remediation Committee is provided to guarantee the fund's independence and to observe the fund's operation. The official start is given through the accreditation of BOFAS by the Inter-regional Soil Remediation Committee. To calculate the amount that would be necessary for the remediation of the soil contamination at petrol stations and the contribution to the fund, an economical research has been carried out. This research indicated that the total cost for the remediation of the soil contamination at petrol stations in Belgium is situated between 400 and 450 million EUR. BOFAS has calculated that 5.000 petrol stations can comply with the conditions mentioned in the cooperation agreement. Operators, Owners or Actual users can submit an application if they comply with the legally

  13. Electrokinetic remediation of a copper contaminated soil - experiments and 1-D model

    Energy Technology Data Exchange (ETDEWEB)

    Vereda Alonso, C.; Hansen, H.K. [Inst. for Geologi and Geoteknik, Danmarks Tekniske Univ., Lyngby (Denmark); Gomez Lahoz, C.; Rodriguez Maroto, J.M. [Dept. de Ingenieria Quimica, Univ. de Malaga (Spain)

    2001-07-01

    In this work, a set of electrokinetic soil remediation experiments has been performed in a column containing a commercial standard kaolin that was previously contaminated with copper. The profile evolution of copper concentration and pH along the soil column was obtained from these experiments. A one-dimensional numerical model has been developed to simulate the experimental results obtained from these experiments. (orig.)

  14. Spectral Characteristics of Salinized Soils during Microbial Remediation Processes.

    Science.gov (United States)

    Ma, Chuang; Shen, Guang-rong; Zhi, Yue-e; Wang, Zi-jun; Zhu, Yun; Li, Xian-hua

    2015-09-01

    In this study, the spectral reflectance of saline soils, the associated soil salt content (SSC) and the concentrations of salt ions were measured and analysed by tracing the container microbial remediation experiments for saline soil (main salt is sodium chloride) of Dongying City, Shandong Province. The sensitive spectral reflectance bands of saline soils to SSC, Cl- and Na+ in the process of microbial remediation were analysed. The average-dimension reduction of these bands was conducted by using a combination of correlation coefficient and decision coefficient, and by gradually narrowing the sampling interval method. Results showed that the tendency and magnitude of the average spectral reflectance in all bands of saline soils during the total remediation processes were nearly consistent with SSC and with Cl- coocentration, respectively. The degree of salinity of the soil, including SSC and salt ion concentrations, had a significant positive correlation with the spectral reflectance of all bands, particularly in the near-infrared band. The optimal spectral bands of SSC were 1370 to 1445 nm and 1447 to 1608 nm, whereas the optimal spectral bands of Cl- and Na+ were 1336 to 1461 nm and 1471 to 1561 nm, respectively. The relationship model among SSC, soil salt ion concentrations (Cl- and Na+) and soil spectral reflectance of the corresponding optimal spectral band was established. The largest R2 of relationship model between SSC and the average reflectance of associated optimal band reached to 0.95, and RMSEC and RMSEP were 1.076 and 0.591, respectively. Significant statistical analysis of salt factors and soil reflectance for different microbial remediation processes indicated that the spectral response characteristics and sensitivity of SSC to soil reflectance, which implied the feasibility of high spectrum test on soil microbial remediation monitoring, also provided the basis for quick nondestructive monitoring soil bioremediation process by soil spectral

  15. Predicting the phytoextraction duration to remediate heavy metal contaminated soils

    NARCIS (Netherlands)

    Koopmans, G.F.; Römkens, P.F.A.M.; Song, J.; Temminghoff, E.J.M.; Japenga, J.

    2007-01-01

    The applicability of phytoextraction to remediate soils contaminated with heavy metals (HMs) depends on, amongst others, the duration before remediation is completed. The impact of changes in the HM content in soil occurring during remediation on plant uptake has to be considered in order to obtain

  16. Electrokinetic remediation of contaminated soils

    International Nuclear Information System (INIS)

    Lindgren, E.R.; Kozak, M.W.; Mattson, E.D.

    1991-01-01

    Electrokinetic remediation of contaminated soil has been demonstrated for saturated and unsaturated sand in preliminary experiments using a novel transport visualization technique. Large anionic organic dyes were mixed with a portion of soil and the rate of electromigration of the dye in an imposed electric field was monitored photographically. One of the fastest current-normalized electromigration rates was measured in the driest sand, which contained 7% water by weight. This moisture content is typical of the moisture content in the unsaturated zone of subsurface native soils found in New Mexico. The characteristics of the electromigration were similar in both the saturated and unsaturated sand. The leading edge of the dye migration front was diffuse while the trailing edge was sharp and concentrated. This and other observed behavior may indicate a concentration effect, where the electromigration rate of dilute dye is greater than that of concentrated dye. The soil left after the trailing edge passed seemed to contain no residual dye in both the saturated and unsaturated cases. The success of demonstrating electromigration of large molecules in unsaturated soil is encouraging and indicates that it may be feasible to remediate in situ anionic heavy metals such as chromate from unsaturated soil with electrokinetic techniques. 23 refs., 7 figs

  17. Electrokinetic remediation of contaminated soils

    International Nuclear Information System (INIS)

    Lindgren, E.R.; Kozak, M.W.; Mattson, E.D.

    1991-01-01

    Electrokinetic remediation of contaminated soil has been demonstrated for saturated and unsaturated sand in preliminary experiments using a novel transport visualization technique. Large anionic organic dyes were mixed with a portion of soil and the rate of electromigration of the dye in an imposed electric field was monitored photographically. One of the fastest current-normalized electromigration rates was measured in the driest sand, which contained 7% water by-weight. This moisture content is typical of the moisture content in the unsaturated zone of subsurface native soils found in New Mexico. The characteristics of the electromigration were similar in both the saturated and unsaturated sand. The leading edge of the dye migration front was diffuse while the trailing edge was sharp and concentrated. This and other observed behavior may indicate a concentration effect, where the electromigration rate of dilute dye is greater than that of concentrated dye. The soil left after the trailing edge passed seemed to contain no residual dye in both the saturated and unsaturated cases. The success of demonstrating electromigration of large molecules in unsaturated soil is encouraging and indicates that it may be feasible to remediate in situ anionic heavy metals such as chromate from unsaturated soil with electrokinetic techniques

  18. Use of surfactants for the remediation of contaminated soils: a review.

    Science.gov (United States)

    Mao, Xuhui; Jiang, Rui; Xiao, Wei; Yu, Jiaguo

    2015-03-21

    Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Physicochemical and biological quality of soil in hexavalent chromium-contaminated soils as affected by chemical and microbial remediation.

    Science.gov (United States)

    Liao, Yingping; Min, Xiaobo; Yang, Zhihui; Chai, Liyuan; Zhang, Shujuan; Wang, Yangyang

    2014-01-01

    Chemical and microbial methods are the main remediation technologies for chromium-contaminated soil. These technologies have progressed rapidly in recent years; however, there is still a lack of methods for evaluating the chemical and biological quality of soil after different remediation technologies have been applied. In this paper, microbial remediation with indigenous bacteria and chemical remediation with ferrous sulphate were used for the remediation of soils contaminated with Cr(VI) at two levels (80 and 1,276 mg kg(-1)) through a column leaching experiment. After microbial remediation with indigenous bacteria, the average concentration of water-soluble Cr(VI) in the soils was reduced to less than 5.0 mg kg(-1). Soil quality was evaluated based on 11 soil properties and the fuzzy comprehensive assessment method, including fuzzy mathematics and correlative analysis. The chemical fertility quality index was improved by one grade using microbial remediation with indigenous bacteria, and the biological fertility quality index increased by at least a factor of 6. Chemical remediation with ferrous sulphate, however, resulted in lower levels of available phosphorus, dehydrogenase, catalase and polyphenol oxidase. The result showed that microbial remediation with indigenous bacteria was more effective for remedying Cr(VI)-contaminated soils with high pH value than chemical remediation with ferrous sulphate. In addition, the fuzzy comprehensive evaluation method was proven to be a useful tool for monitoring the quality change in chromium-contaminated soils.

  20. Microbial fuel cell driving electrokinetic remediation of toxic metal contaminated soils.

    Science.gov (United States)

    Habibul, Nuzahat; Hu, Yi; Sheng, Guo-Ping

    2016-11-15

    An investigation of the feasibility of in-situ electrokinetic remediation for toxic metal contaminated soil driven by microbial fuel cell (MFC) is presented. Results revealed that the weak electricity generated from MFC could power the electrokinetic remediation effectively. The metal removal efficiency and its influence on soil physiological properties were also investigated. With the electricity generated through the oxidation of organics in soils by microorganisms, the metals in the soils would mitigate from the anode to the cathode. The concentrations of Cd and Pb in the soils increased gradually through the anode to the cathode regions after remediation. After about 143days and 108 days' operation, the removal efficiencies of 31.0% and 44.1% for Cd and Pb at the anode region could be achieved, respectively. Soil properties such as pH and soil conductivity were also significantly redistributed from the anode to the cathode regions. The study shows that the MFC driving electrokinetic remediation technology is cost-effective and environmental friendly, with a promising application in soil remediation. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Microemulsion-enhanced remediation of soils contaminated with organochlorine pesticides.

    Science.gov (United States)

    Zhang, Yanlin; Wong, Jonathan W C; Zhao, Zhenyong; Selvam, Ammaiyappan

    2011-12-01

    Soil contaminated by organic pollutants, especially chlorinated aromatic compounds such as DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane), is an environmental concern because of the strong sorption of organochlorine pesticide onto the soil matrix and persistence in the environment. The remediation of organochlorine pesticide contaminated soils through microemulsion is an innovative technology to expedite this process. The remediation efficiency was evaluated by batch experiments through studying the desorption of DDT and hexachlorocyclohexane (y-HCH) and sorption of microemulsion composed of Triton X-100, 1-pentanol and linseed oil in the soil-surfactant-water suspension system. The reduction of desorption efficiency caused by the sorption loss of microemulsion components onto the soil could be corrected by the appropriate adjustment of C/S (Cosurfactant/Surfactant) and O/S (Oil/Surfactant) ratio. The C/S and O/S ratios of 1:2 and 3:20 were suitable to desorb DDT and gamma-HCH from the studied soils because of the lower sorption of Triton X-100 onto the soil. Inorganic salts added in microemulsion increased the pesticides desorption efficiency of pesticides and calcium chloride has a stronger ability to enhance the desorption of DDT than sodium chloride. From the remediation perspective, the balance of surfactant or cosurfactant sorbed to soil and desorption efficiency should be taken into consideration to enhance the remediation of soils contaminated by organochlorine pesticides.

  2. Steam Injection For Soil And Aquifer Remediation

    Science.gov (United States)

    The purpose of this Issue Paper is to provide to those involved in assessing remediation technologies for specific sites basic technical information on the use of steam injection for the remediation of soils and aquifers that are contaminated by...

  3. An expert support model for in situ soil remediation

    NARCIS (Netherlands)

    Okx, J.P.; Stein, A.

    2000-01-01

    This article presents an expert support model for in situ soil remediation. It combines knowledge and experiences obtained from previous in situ soil remediations. The aim of this model is to optimise knowledge transfer among the various parties involved in contaminated site management. Structured

  4. Current state and future prospects of remedial soil protection. Background

    Energy Technology Data Exchange (ETDEWEB)

    Frauenstein, Joerg

    2009-08-15

    The legal basis for soil protection in the Federal Republic of Germany is: -The Act on Protection against Harmful Changes to Soil and on Rehabilitation of Contaminated Sites (Federal Soil Protection Act) (Bundes-Bodenschutzgesetz - BBodSchG) of 1998 [1] -The Federal Soil Protection and Contaminated Sites Ordinance (BBodSchV) of 1999 [2]. In Germany, the Federal Government has legislative competence in the field of soil protection. The Lander (German federal states), in turn, are responsible for enforcement of the BBodSchG and the BBodSchV; they may also issue supplementary procedural regulations. According to Article 1 BBodschG, the purpose of the Act is inter alia to protect and restore the functions of the soil on a permanent sustainable basis. These actions shall include prevention of harmful soil changes as well as rehabilitating soil, contaminated sites and waters contaminated by such sites in such a way that any contamination remains permanently below the hazard threshold. Whilst prevention aims to protect and preserve soil functions on a long-term basis, the object of remediation is mainly to avert concrete hazards in a spatial, temporal and manageable causative context. ''Remedial soil protection'' encompasses a tiered procedure in which a suspicion is verified successively and with least-possible effort and in which the circumstances of the individual case at hand are taken into account in deciding whether or not a need for remediation exists. It comprises the systematic stages of identifying, investigating and assessing suspect sites and sites suspected of being contaminated with a view to their hazard potential, determining whether remediation is necessary, remediating identified harmful soil changes and contaminated sites, and carrying out, where necessary, aftercare measures following final inspection of the remedial measure. (orig.)

  5. Case study of shallow soil mixing and soil vacuum extraction remediation project

    International Nuclear Information System (INIS)

    Carey, M.J.; Day, S.R.; Pinewski, R.; Schroder, D.

    1995-01-01

    Shallow Soil Mixing (SSM) and Soil Vacuum Extraction (SVE) are techniques which have been increasingly relied on for the insitu remediation of contaminated soils. The primary applications of SSM have been to mix cement, bentonite, or other reagents to modify properties and thereby remediate contaminated soils or sludges. Soil vacuum extraction has been used at numerous applications for insitu removal of contaminants from soils. At a recent project in southern Ohio, the two technologies were integrated and enhanced to extract volatile organic compounds (VOCs) from soils at a Department of Energy facility. Advantages of the integrated SSM/SVE technology over alternative technologies include a relatively rapid remediation compared to other in-situ techniques at a lower cost, less exposure of waste to the surface environment and elimination of off-site disposal. These advantages led to the selection of the use of both technologies on the project in Southern Ohio. The information presented in this paper is intended to provide Engineers and owners with the level of understanding necessary to apply soil mixing and vacuum extraction technology to a specific site. The most important steps in implementing the technology are site investigation, feasibility estimate, selection of performance criteria, selection of appropriate materials, bench scale testing and construction

  6. Clean-up criteria for remediation of contaminated soils

    International Nuclear Information System (INIS)

    Nguyen, H.D.; Wilson, J.R.; Sato, Chikashi

    1997-01-01

    'How clean is clean?' is a question commonly raised in the remediation of contaminated soils. To help with the answer, criteria are proposed to serve as guidelines for remedial actions and to define a clean-up level such that the remaining contaminant residuals in the soil will not violate the Drinking Water Standards (DWS). The equations for computing those criteria are developed from the principle of conservation of mass and are functions of the maximum concentration level in the water (MCL) and the sorption coefficient. A multiplier, ranging from 10 to 1000, is also factored into the soil standard equation to reflect the effectiveness of various remediation techniques. Maximum allowable concentration in the soil (MSCL) is presented for several contaminants which are being regulated at the present time. Future modifications are recommended for better estimates of the MSCLs as additional transport mechanisms are incorporated to account for other potentially dominant effects

  7. Soil remediation of a former power plant site in Tulita, Northwest Territories

    International Nuclear Information System (INIS)

    Pouliot, Y.; Thomassin-Lacroix, E.; Moreau, N.

    2005-01-01

    This paper outlines major stages of an ongoing remediation project caused by a power generating plant in the Dene Hamlet of Tulita. High levels of soil contamination were caused by the plant's operations as well as accidental petroleum hydrocarbon (PHC) spills. The decommissioning of the plant required that the site be remediated. Challenges faced by the remediators included the high level of contamination, the remote location of the community, as well as the fact that the site was located in the centre of the community. In addition, the soil in the impacted site was fine, and a 20 cm thick layer of peat acted as sponge, absorbing and trapping hydrocarbons. Remedial criteria was outlined according to Canada-Wide Standards for fine-grained soil in an industrial setting. The technology used for the project was Biopile, a process consisting of installing wells in the contaminated zone in order to provide the aeration required for PHC biodegradation and to condition the soil on a regular basis in order to promote optimal treatment conditions throughout the impacted material. Results indicated that the first 2 months were successful in reducing initial PHC levels. However, the following treatment season did not show as much degradation. An investigation revealed that nitrogen and phosphorus levels were insufficient to sustain microbial activity, as a result of lower than normal temperatures in the area for that season. Nutrients were added to the soil to re-establish the appropriate treatment conditions. It was concluded that the technology used presented numerous advantages. Overall disturbance of the area was reduced, and allowed other measures to be implemented, including segregation of the highly impacted peat layer. It was expected that remediation objectives for the entire site will be met by July 2005. 3 refs., 3 tabs

  8. Soil remediation of a former power plant site in Tulita, Northwest Territories

    Energy Technology Data Exchange (ETDEWEB)

    Pouliot, Y.; Thomassin-Lacroix, E. [Biogenie Inc., Lachenaie, PQ (Canada); Moreau, N. [Biogenie, Quebec City, PQ (Canada)

    2005-07-01

    This paper outlines major stages of an ongoing remediation project caused by a power generating plant in the Dene Hamlet of Tulita. High levels of soil contamination were caused by the plant's operations as well as accidental petroleum hydrocarbon (PHC) spills. The decommissioning of the plant required that the site be remediated. Challenges faced by the remediators included the high level of contamination, the remote location of the community, as well as the fact that the site was located in the centre of the community. In addition, the soil in the impacted site was fine, and a 20 cm thick layer of peat acted as sponge, absorbing and trapping hydrocarbons. Remedial criteria was outlined according to Canada-Wide Standards for fine-grained soil in an industrial setting. The technology used for the project was Biopile, a process consisting of installing wells in the contaminated zone in order to provide the aeration required for PHC biodegradation and to condition the soil on a regular basis in order to promote optimal treatment conditions throughout the impacted material. Results indicated that the first 2 months were successful in reducing initial PHC levels. However, the following treatment season did not show as much degradation. An investigation revealed that nitrogen and phosphorus levels were insufficient to sustain microbial activity, as a result of lower than normal temperatures in the area for that season. Nutrients were added to the soil to re-establish the appropriate treatment conditions. It was concluded that the technology used presented numerous advantages. Overall disturbance of the area was reduced, and allowed other measures to be implemented, including segregation of the highly impacted peat layer. It was expected that remediation objectives for the entire site will be met by July 2005. 3 refs., 3 tabs.

  9. Effect of Remediation Parameters on in-Air Ambient Dose Equivalent Rates When Remediating Open Sites with Radiocesium-contaminated Soil.

    Science.gov (United States)

    Malins, Alex; Kurikami, Hiroshi; Kitamura, Akihiro; Machida, Masahiko

    2016-10-01

    Calculations are reported for ambient dose equivalent rates [H˙*(10)] at 1 m height above the ground surface before and after remediating radiocesium-contaminated soil at wide and open sites. The results establish how the change in H˙*(10) upon remediation depends on the initial depth distribution of radiocesium within the ground, on the size of the remediated area, and on the mass per unit area of remediated soil. The remediation strategies considered were topsoil removal (with and without recovering with a clean soil layer), interchanging a topsoil layer with a subsoil layer, and in situ mixing of the topsoil. The results show the ratio of the radiocesium components of H˙*(10) post-remediation relative to their initial values (residual dose factors). It is possible to use the residual dose factors to gauge absolute changes in H˙*(10) upon remediation. The dependency of the residual dose factors on the number of years elapsed after fallout deposition is analyzed when remediation parameters remain fixed and radiocesium undergoes typical downward migration within the soil column.

  10. The effect of soil type on the electrodialytic remediation of lead-contaminated soil

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ottosen, Lisbeth M.; Harmon, Thomas C.

    2007-01-01

    experiments with ten representative industrially Pb-contaminated surface soils. Results indicate that Pb-speciation is of primary importance. Specifically, organic matter and stable compounds like PbCrO4 can impede and possibly even preclude soil remediation. In soils rich in carbonate, where the acidic front...... to the catholyte. Thus, the presence of carbonate negatively influences the remediation time. Pb bound to soluble organic matter is also transported towards the anolyte during EDR. The primary effect of the mainly insoluble organic matter commonly present in surface soil is however to immobilize Pb and impede...

  11. Soil contamination with cadmium, consequences and remediation using organic amendments.

    Science.gov (United States)

    Khan, Muhammad Amjad; Khan, Sardar; Khan, Anwarzeb; Alam, Mehboob

    2017-12-01

    Cadmium (Cd) contamination of soil and food crops is a ubiquitous environmental problem that has resulted from uncontrolled industrialization, unsustainable urbanization and intensive agricultural practices. Being a toxic element, Cd poses high threats to soil quality, food safety, and human health. Land is the ultimate source of waste disposal and utilization therefore, Cd released from different sources (natural and anthropogenic), eventually reaches soil, and then subsequently bio-accumulates in food crops. The stabilization of Cd in contaminated soil using organic amendments is an environmentally friendly and cost effective technique used for remediation of moderate to high contaminated soil. Globally, substantial amounts of organic waste are generated every day that can be used as a source of nutrients, and also as conditioners to improve soil quality. This review paper focuses on the sources, generation, and use of different organic amendments to remediate Cd contaminated soil, discusses their effects on soil physical and chemical properties, Cd bioavailability, plant uptake, and human health risk. Moreover, it also provides an update of the most relevant findings about the application of organic amendments to remediate Cd contaminated soil and associated mechanisms. Finally, future research needs and directions for the remediation of Cd contaminated soil using organic amendments are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Low-concentration tailing and subsequent quicklime-enhanced remediation of volatile chlorinated hydrocarbon-contaminated soils by mechanical soil aeration.

    Science.gov (United States)

    Ma, Yan; Du, Xiaoming; Shi, Yi; Xu, Zhu; Fang, Jidun; Li, Zheng; Li, Fasheng

    2015-02-01

    Mechanical soil aeration has long been regarded as an effective ex-situ remediation technique and as suitable for remediation of large-scale sites contaminated by volatile organic compounds (VOCs) at low cost. However, it has been reported that the removal efficiency of VOCs from soil is relatively low in the late stages of remediation, in association with tailing. Tailing may extend the remediation time required; moreover, it typically results in the presence of contaminants residues at levels far exceeding regulations. In this context, the present study aimed to discuss the tailing that occurs during the process of remediation of soils contaminated artificially with volatile chlorinated hydrocarbons (VCHs) and to assess possible quicklime-enhanced removal mechanisms. The results revealed the following conclusions. First, temperature and aeration rate can be important controls on both the timing of appearance of tailing and the levels of residual contaminants. Furthermore, the addition of quicklime to soil during tailing can reduce the residual concentrations rapidly to below the remedial target values required for site remediation. Finally, mechanical soil aeration can be enhanced using quicklime, which can improve the volatilization of VCHs via increasing soil temperature, reducing soil moisture, and enhancing soil permeability. Our findings give a basic understanding to the elimination of the tailing in the application of mechanical soil aeration, particularly for VOCs-contaminated soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Risk characterization and remedial management of TPH-affected soils

    International Nuclear Information System (INIS)

    Smith, J.; Von Burg, R.; Preslo, L.; Lakin, M.

    1994-01-01

    A risk-based remedial program for petroleum hydrocarbon affected soils has been implemented at a large land parcel in California. The site is the former location of a manufacturing facility that had been in operation since the 1940s. As a result of various activities related to parts manufacturing, several large areas of soil were found to contain various petroleum products. The primary sources of petroleum hydrocarbons included cutting oils, lubricating oils, fuels, and hydraulic oils associated with the site operations. Concentrations of total petroleum hydrocarbons (TPH) as high as 100,000 mg/kg were identified in soil. These high concentrations of TPH were identified at depths up to 60 feet below ground surface (bgs), with the vadose zone extending to depths of more than 150 feet bgs. Within California, traditional cleanup levels for TPH-affected soils typically range from 100 to 1,000 mg/kg. Because of the client's desire to sell the property for rapid development, the remedial alternative of excavation and off-haul was deemed too time consuming and costly. The estimated costs associated with this remediation which potentially involved soil removal to 100--120 feet exceeded $20 million and could take up to one year to complete. To meet the schedule requirements for site remediations as well as significantly reduce the overall project cost, the authors undertook a risk-based approach to assess if remediation of the TPH-affected soils was required

  14. The relative influence of electrokinetic remediation design on the removal of As, Cu, Pb and Sb from shooting range soils

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2018-01-01

    to simultaneously optimise the removal by applying a stirred set-up, placement of the anode directly in the soil suspension, sieving the soil (analysis is a valuable tool for evaluating remediation measures depending soil...... and analysis was applied for assessing the efficiency of electrodialytic remediation treatment and variable importance varied for each of the studied metals. In general, applying a stirred set-up improved the metal removal, acidification time and reduced the energy consumption. The placement of the anode...... directly in the soil did not significantly influence the removal of Al, Mg, Mn, As and Pb, while moderately influencing the removal of Cu. Multivariate analysis (projections onto latent structures) revealed similar variable importance and optimal settings for removal of Cu and Pb. It is hence possible...

  15. Is soil dressing a way once and for all in remediation of arsenic contaminated soils? A case study of arsenic re-accumulation in soils remediated by soil dressing in Hunan Province, China.

    Science.gov (United States)

    Su, Shiming; Bai, Lingyu; Wei, Caibing; Gao, Xiang; Zhang, Tuo; Wang, Yanan; Li, Lianfang; Wang, Jinjin; Wu, Cuixia; Zeng, Xibai

    2015-07-01

    The investigation of arsenic (As) re-accumulation in an area previously remediated by soil dressing will help in sustainable controlling the risks of As to local ecosystems and should influence management decisions about remediation strategies. In this study, As content in an area remediated by soil dressing and the possible As accumulation risk in agricultural products were investigated. The results indicated that after 7 years of agricultural activities, the average As content (24.6 mg kg(-1)) in surface soil of the investigated area increased by 83.6% compared with that (13.4 mg kg(-1)) in clean soil. Of the surface soil samples (n = 88), 21.6% had As levels that exceeded the limits of the Environmental Quality Standard for Soils of China (GB 15618-1995) and 98.9% of the surface soil samples with As contents exceeding that in clean soil was observed. Soil dressing might be not a remediation method once and for all in some contaminated areas, even though no significant difference in available As content was found between clean (0.18 mg kg(-1)) and surface (0.22 mg kg(-1)) soils. The foreign As in surface soil of the investigated area mainly specifically sorbed with soil colloid or associated with hydrous oxides of Fe and Al, or existed in residual fraction. The upward movement of contaminated soil from the deeper layers and the atmospheric deposition of slag particles might be responsible for the re-accumulation of As in the investigated area. Decreases in soil pH in the investigated soils and the fact that no plant samples had As levels exceeding the limits of the National Food Safety Standards for Contaminants of China (GB 2762-2012) were also observed.

  16. Electrodialytic Remediation of Soil Fines (<63μm) in Suspension

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ottosen, Lisbeth M.; Ferreira, Célia

    2007-01-01

    Current treatment of the remaining soil fines from soil wash is onerous and expensive, and therefore, in this work, we investigated the feasibility of electrodialytic remediation (EDR) as an alternative treatment. The study focuses on EDR efficiency as a function of current strength, liquid......-exchange membrane increased the pH, and this resulted in decreased remediation efficiency. It was shown that complete remediation of the soil-fines is possible, with the majority of the Pb being transported into the catholyte and precipitated at the cathode. Based on the results it is recommended that EDR...

  17. Electrodialytic Remediation of Soil Polluted with Copper from Wood Preservation

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik; Laursen, Søren

    1997-01-01

    The principle of electrodialytic soil remediation was tested in six experiments on a copper polluted loamy sand. It was possible to decontaminate from 1360 to below 40 mg of Cu/kg of dry soil......The principle of electrodialytic soil remediation was tested in six experiments on a copper polluted loamy sand. It was possible to decontaminate from 1360 to below 40 mg of Cu/kg of dry soil...

  18. Electrodialytic Soil Remediation. Improved conditions and acceleration of the process by addition of desorbing agents to the soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik; Hansen, Lene

    1998-01-01

    The principel of electrodialytic soil remediation was improved when ammonia was added to a calcareous copper polluted soil......The principel of electrodialytic soil remediation was improved when ammonia was added to a calcareous copper polluted soil...

  19. Effects of different remediation treatments on crude oil contaminated saline soil.

    Science.gov (United States)

    Gao, Yong-Chao; Guo, Shu-Hai; Wang, Jia-Ning; Li, Dan; Wang, Hui; Zeng, De-Hui

    2014-12-01

    Remediation of the petroleum contaminated soil is essential to maintain the sustainable development of soil ecosystem. Bioremediation using microorganisms and plants is a promising method for the degradation of crude oil contaminants. The effects of different remediation treatments, including nitrogen addition, Suaeda salsa planting, and arbuscular mycorrhiza (AM) fungi inoculation individually or combined, on crude oil contaminated saline soil were assessed using a microcosm experiment. The results showed that different remediation treatments significantly affected the physicochemical properties, oil contaminant degradation and bacterial community structure of the oil contaminated saline soil. Nitrogen addition stimulated the degradation of total petroleum hydrocarbon significantly at the initial 30d of remediation. Coupling of different remediation techniques was more effective in degrading crude oil contaminants. Applications of nitrogen, AM fungi and their combination enhanced the phytoremediation efficiency of S. salsa significantly. The main bacterial community composition in the crude oil contaminated saline soil shifted with the remediation processes. γ-Proteobacteria, β-Proteobacteria, and Actinobacteria were the pioneer oil-degraders at the initial stage, and Firmicutes were considered to be able to degrade the recalcitrant components at the later stage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Remediation of soils contaminated with heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Boni, M.R.; D' Aprile, L. [Univ. of Rome ' ' La Sapienza' ' , Dept. of Hydraulic Transportation and Roads (Italy)

    2001-07-01

    In December 1999 Italy issued the national regulation (DM 471/99) for the clean-up of contaminated sites. This regulation applies both to derelict and to still operating industrial plants and waste management facilities. Target concentration values for clean-up interventions are issued and the requirements for design and planning of technical operation are defined. The selection of the appropriate clean-up technology are based on the following main criteria: - reduce the concentration in environmental media and the migration of pollutants without removing soil off-site; - in order to reduce contaminated material removal and transportation, remedial actions of soil, subsoil and groundwater should preferably be based on in-situ treatments. In-situ technologies commonly applied in Italy to the remediation of soils contaminated by heavy metals (As, Cd, Cr, Hg, Pb) are: - containment (caps, vertical barriers); - soil flushing; - cement based solidification/stabilization. (orig.)

  1. Soil and ground-water remediation techniques

    International Nuclear Information System (INIS)

    Beck, P.

    1996-01-01

    Urban areas typically contain numerous sites underlain by soils or ground waters which are contaminated to levels that exceed clean-up guidelines and are hazardous to public health. Contamination most commonly results from the disposal, careless use and spillage of chemicals, or the historic importation of contaminated fill onto properties undergoing redevelopment. Contaminants of concern in soil and ground water include: inorganic chemicals such as heavy metals; radioactive metals; salt and inorganic pesticides, and a range of organic chemicals included within petroleum fuels, coal tar products, PCB oils, chlorinated solvents, and pesticides. Dealing with contaminated sites is a major problem affecting all urban areas and a wide range of different remedial technologies are available. This chapter reviews the more commonly used methods for ground-water and soil remediation, paying particular regard to efficiency and applicability of specific treatments to different site conditions. (author). 43 refs., 1 tab., 27 figs

  2. Lead (II) removal from natural soils by enhanced electrokinetic remediation.

    Science.gov (United States)

    Altin, Ahmet; Degirmenci, Mustafa

    2005-01-20

    Electrokinetic remediation is a very effective method to remove metal from fine-grained soils having low adsorption and buffering capacity. However, remediation of soil having high alkali and adsorption capacity via the electrokinetic method is a very difficult process. Therefore, enhancement techniques are required for use in these soil types. In this study, the effect of the presence of minerals having high alkali and cation exchange capacity in natural soil polluted with lead (II) was investigated by means of the efficiency of electrokinetic remediation method. Natural soil samples containing clinoptilolite, gypsum and calcite minerals were used in experimental studies. Moreover, a sample containing kaolinite minerals was studied to compare with the results obtained from other samples. Best results for soils bearing alkali and high sorption capacity minerals were obtained upon addition of 3 mol AcH and application of 20 V constant potential after a remediation period of 220 h. In these test conditions, lead (II) removal efficiencies for these samples varied between 60% and 70% up to 0.55 normalized distance. Under the same conditions, removal efficiencies in kaolinite sample varied between 50% and 95% up to 0.9 normalized distance.

  3. Remediation of multiple heavy metal-contaminated soil through the combination of soil washing and in situ immobilization.

    Science.gov (United States)

    Zhai, Xiuqing; Li, Zhongwu; Huang, Bin; Luo, Ninglin; Huang, Mei; Zhang, Qiu; Zeng, Guangming

    2018-09-01

    The remediation of heavy metal-contaminated soils is a great challenge for global environmental sciences and engineering. To control the ecological risks of heavy metal-contaminated soil more effectively, the present study focused on the combination of soil washing (with FeCl 3 ) and in situ immobilization (with lime, biochar, and black carbon). The results showed that the removal rate of Cd, Pb, Zn, and Cu was 62.9%, 52.1%, 30.0%, and 16.7%, respectively, when washed with FeCl 3 . After the combined remediation (immobilization with 1% (w/w) lime), the contaminated soils showed 36.5%, 73.6%, 70.9%, and 53.4% reductions in the bioavailability of Cd, Cu, Pb, and Zn (extracted with 0.11M acetic acid), respectively, than those of the soils washed with FeCl 3 only. However, the immobilization with 1% (w/w) biochar or 1% (w/w) carbon black after washing exhibited low effects on stabilizing the metals. The differences in effects between the immobilization with lime, biochar, and carbon black indicated that the soil pH had a significant influence on the lability of heavy metals during the combined remediation process. The activity of the soil enzymes (urease, sucrase, and catalase) showed that the addition of all the materials, including lime, biochar, and carbon black, exhibited positive effects on microbial remediation after soil washing. Furthermore, lime was the most effective material, indicating that low soil pH and high acid-soluble metal concentrations might restrain the activity of soil enzymes. Soil pH and nutrition were the major considerations for microbial remediation during the combined remediation. These findings suggest that the combination of soil washing and in situ immobilization is an effective method to amend the soils contaminated with multiple heavy metals. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Research factors of the electrochemical remediation clay soils from the nitrates

    Energy Technology Data Exchange (ETDEWEB)

    Korolev, V.A.; Babakina, O.A. [Moscow State Univ. (Russian Federation)

    2001-07-01

    The electrokinetic's methods are prevalent [1, 2], but abilities of the method for remediation nitrates contaminated soils are studied insufficiently. The investigations of effectiveness electrochemical remediation are complicated by processes of reduction nitrates to nitrites (that are more toxic) and then to nitrogen in soil under the constant electric current. Therefore, the objectives of the research was following: - Evaluate mechanism of electrokinetic's removing nitrates from soil; - Evaluate basic value of moisture and alkalinity influence for electrochemical remediation of soil from nitrates; - Determine flow-through regime effect on electrokinetic's treating. (orig.)

  5. Geostatistical approach for assessing soil volumes requiring remediation: validation using lead-polluted soils underlying a former smelting works.

    Science.gov (United States)

    Demougeot-Renard, Helene; De Fouquet, Chantal

    2004-10-01

    Assessing the volume of soil requiring remediation and the accuracy of this assessment constitutes an essential step in polluted site management. If this remediation volume is not properly assessed, misclassification may lead both to environmental risks (polluted soils may not be remediated) and financial risks (unexpected discovery of polluted soils may generate additional remediation costs). To minimize such risks, this paper proposes a geostatistical methodology based on stochastic simulations that allows the remediation volume and the uncertainty to be assessed using investigation data. The methodology thoroughly reproduces the conditions in which the soils are classified and extracted at the remediation stage. The validity of the approach is tested by applying it on the data collected during the investigation phase of a former lead smelting works and by comparing the results with the volume that has actually been remediated. This real remediated volume was composed of all the remediation units that were classified as polluted after systematic sampling and analysis during clean-up stage. The volume estimated from the 75 samples collected during site investigation slightly overestimates (5.3% relative error) the remediated volume deduced from 212 remediation units. Furthermore, the real volume falls within the range of uncertainty predicted using the proposed methodology.

  6. Remediating soils: Designing biochars to meet the need

    Science.gov (United States)

    Biochar, the porous, carbon-rich product of pyrolysis, may provide an additional tool for remediating both metal and organic contaminated soils and for reducing other soil limitations. Soils contaminated with metals, organics or limited in some other way is a world-wide problem...

  7. Bioavailability-Based In Situ Remediation To Meet Future Lead (Pb) Standards in Urban Soils and Gardens.

    Science.gov (United States)

    Henry, Heather; Naujokas, Marisa F; Attanayake, Chammi; Basta, Nicholas T; Cheng, Zhongqi; Hettiarachchi, Ganga M; Maddaloni, Mark; Schadt, Christopher; Scheckel, Kirk G

    2015-08-04

    Recently the Centers for Disease Control and Prevention lowered the blood Pb reference value to 5 μg/dL. The lower reference value combined with increased repurposing of postindustrial lands are heightening concerns and driving interest in reducing soil Pb exposures. As a result, regulatory decision makers may lower residential soil screening levels (SSLs), used in setting Pb cleanup levels, to levels that may be difficult to achieve, especially in urban areas. This paper discusses challenges in remediation and bioavailability assessments of Pb in urban soils in the context of lower SSLs and identifies research needs to better address those challenges. Although in situ remediation with phosphate amendments is a viable option, the scope of the problem and conditions in urban settings may necessitate that SSLs be based on bioavailable rather than total Pb concentrations. However, variability in soil composition can influence bioavailability testing and soil amendment effectiveness. More data are urgently needed to better understand this variability and increase confidence in using these approaches in risk-based decision making, particularly in urban areas.

  8. Initial screening of thermal desorption for soil remediation

    International Nuclear Information System (INIS)

    Yezzi, J.J. Jr.; Tafuri, A.N.; Rosenthal, S.; Troxler, W.L.

    1994-01-01

    Petroleum-contaminated soils--caused by spills, leaks, and accidental discharges--exist at many sites throughout the United States. Thermal desorption technologies which are increasingly being employed to treat these soils, have met soil cleanup criteria for a variety of petroleum products. Currently the United States Environmental Protection Agency is finalizing a technical report entitled Use of Thermal Desorption for Treating Petroleum-Contaminated Soils to assist remedial project managers, site owners, remediation contractors, and equipment vendors in evaluating the use of thermal desorption technologies for petroleum-contaminated soil applications. The report will present a three-level screening method to help a reader predict the success of applying thermal desorption at a specific site. The objective of screening level one is to determine the likelihood of success in a specific application of thermal desorption. It will take into account procedures for collecting and evaluating data on site characteristics, contaminant characteristics, soil characteristics, and regulatory requirements. This level will establish whether or not thermal desorption should be evaluated further for site remediation, whether treatment should occur on-site or off-site, and if on-site is a viable option, what system size will be most cost-effective. The scope of this paper addresses only screening level one which provides a preliminary assessment of the applicability of thermal desorption to a particular site. This topic encompasses worksheets that are an integral part of the ''user friendly'' screening process. Level one screening provides a foundation for the subsequent two levels which follow a similar ''user friendly'' worksheet approach to evaluating thermal desorption technologies and establishing costs for thermal desorption in an overall remediation project

  9. Dynamics and role of sphingomonas/mycobacterium populations during bio-remediation of weathered PAH-contaminated soils

    International Nuclear Information System (INIS)

    Bastiaens, L.; Ryngaert, A.; Leys, N.; Van Houtven, D.; Gemoets, J.; Goethals, L.; Springael, D.

    2005-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are major soil pollutants in many industrialized countries. During the last decades, a diversity of PAH-degrading micro-organisms has been isolated, suggesting possibilities for bio-remediation. However, biodegradation of PAHs in contaminated soils is not always successful. The low bio-availability of the PAHs is the major problem, especially in weathered soils. In these soils a tightly sorbed PAH-fraction is present which is in general hardly accessible for microorganisms. In order to bio-remedy PAHs also in weathered soils, stimulation of bacteria which have special strategies to access sorbed organics may be a solution. Sphingomonas and Mycobacterium strains may represent such bacteria as (I) they are often isolated as PAH degraders, (II) they are ubiquitously present in PAH-contaminated soils, and (III) they display features which might promote bioavailability. Lab- and pilot-scale experiments were set up in order (A) to study the dynamics of indigenous Sphingomonas and Mycobacterium populations during bio-remediation, and (B) to evaluate their role in the biodegradation of the less bio-available PAH-fraction during treatment of an historic PAH polluted soil. The soil was treated under natural soil moisture conditions and slurry conditions. The experimental set-ups ranged from 2 g lab-scale test to pilot experiments in 1 ton bio-piles and dry solid reactors (50 kg 70% dry matter soil). Different additives were evaluated for stimulation of the Sphingomonas and Mycobacterium population as a strategy to improve bio-remediation of PAHs. The evolution of this microbial population was followed using culture-independent general and genus-specific PCR-based detection methods targeting the 16S rRNA genes of the eu-bacterial community, Mycobacterium or the Sphingomonas populations, respectively. During the different bio-remediation experiments that were conducted, the Mycobacterium population remained very stable, only minor

  10. Dynamics and role of sphingomonas/mycobacterium populations during bio-remediation of weathered PAH-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Bastiaens, L.; Ryngaert, A.; Leys, N.; Van Houtven, D.; Gemoets, J. [Flemish Institute for Technological Research-Vito, Mol (Belgium); Goethals, L. [ENVISAN, Aalst, (Belgium); Springael, D. [Catholic University of Leuven-KUL, Leuven (Belgium)

    2005-07-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are major soil pollutants in many industrialized countries. During the last decades, a diversity of PAH-degrading micro-organisms has been isolated, suggesting possibilities for bio-remediation. However, biodegradation of PAHs in contaminated soils is not always successful. The low bio-availability of the PAHs is the major problem, especially in weathered soils. In these soils a tightly sorbed PAH-fraction is present which is in general hardly accessible for microorganisms. In order to bio-remedy PAHs also in weathered soils, stimulation of bacteria which have special strategies to access sorbed organics may be a solution. Sphingomonas and Mycobacterium strains may represent such bacteria as (I) they are often isolated as PAH degraders, (II) they are ubiquitously present in PAH-contaminated soils, and (III) they display features which might promote bioavailability. Lab- and pilot-scale experiments were set up in order (A) to study the dynamics of indigenous Sphingomonas and Mycobacterium populations during bio-remediation, and (B) to evaluate their role in the biodegradation of the less bio-available PAH-fraction during treatment of an historic PAH polluted soil. The soil was treated under natural soil moisture conditions and slurry conditions. The experimental set-ups ranged from 2 g lab-scale test to pilot experiments in 1 ton bio-piles and dry solid reactors (50 kg 70% dry matter soil). Different additives were evaluated for stimulation of the Sphingomonas and Mycobacterium population as a strategy to improve bio-remediation of PAHs. The evolution of this microbial population was followed using culture-independent general and genus-specific PCR-based detection methods targeting the 16S rRNA genes of the eu-bacterial community, Mycobacterium or the Sphingomonas populations, respectively. During the different bio-remediation experiments that were conducted, the Mycobacterium population remained very stable, only minor

  11. Sustainable remediation of mercury contaminated soils by thermal desorption.

    Science.gov (United States)

    Sierra, María J; Millán, Rocio; López, Félix A; Alguacil, Francisco J; Cañadas, Inmaculada

    2016-03-01

    Mercury soil contamination is an important environmental problem that needs the development of sustainable and efficient decontamination strategies. This work is focused on the application of a remediation technique that maintains soil ecological and environmental services to the extent possible as well as search for alternative sustainable land uses. Controlled thermal desorption using a solar furnace at pilot scale was applied to different types of soils, stablishing the temperature necessary to assure the functionality of these soils and avoid the Hg exchange to the other environmental compartments. Soil mercury content evolution (total, soluble, and exchangeable) as temperature increases and induced changes in selected soil quality indicators are studied and assessed. On total Hg, the temperature at which it is reduced until acceptable levels depends on the intended soil use and on how restrictive are the regulations. For commercial, residential, or industrial uses, soil samples should be heated to temperatures higher than 280 °C, at which more than 80 % of the total Hg is released, reaching the established legal total Hg level and avoiding eventual risks derived from high available Hg concentrations. For agricultural use or soil natural preservation, conversely, maintenance of acceptable levels of soil quality limit heating temperatures, and additional treatments must be considered to reduce available Hg. Besides total Hg concentration in soils, available Hg should be considered to make final decisions on remediation treatments and potential future uses. Graphical Abstract Solar energy use for remediation of soils affected by mercury.

  12. Remediation of contaminated soil by cement treatment

    International Nuclear Information System (INIS)

    Dimovic, S.

    2004-01-01

    This manuscript presents the most applicable remedial technologies for contaminated soil with focus on cement stabilisation/solidification treatment. These technologies are examined in the light of soil contamination with depleted uranium in the large area of south Serbia,after Nato bombing 1999. (author) [sr

  13. Remediation of Oil-Contaminated Soil in Greenland

    DEFF Research Database (Denmark)

    Fritt-Rasmussen, Janne; Jensen, Pernille Erland

    2013-01-01

    This paper present the recent research conducted at the Arctic Technology Centre, where different solutions for remediation of excavated oil contaminated soil in Greenlandic towns were tested. In the first work, soil polluted by light oil was treated with two different nutrient sources (substrate...

  14. Multi-objective decision-making for soil remediation problems

    NARCIS (Netherlands)

    Drunen, van M.A.; Beinat, E.; Nijboer, M.; Okx, J.P.

    2005-01-01

    After deciding whether or not a soil clean-up operation is necessary, the question remains which remedial strategy and technique should be applied. Traditionally, remediation techniques aim at reaching environmental threshold values within the shortest possible time. There is, however, a growing

  15. Impact of electrokinetic remediation on microbial communities within PCP contaminated soil

    International Nuclear Information System (INIS)

    Lear, G.; Harbottle, M.J.; Sills, G.; Knowles, C.J.; Semple, K.T.; Thompson, I.P.

    2007-01-01

    Electrokinetic techniques have been used to stimulate the removal of organic pollutants within soil, by directing contaminant migration to where remediation may be more easily achieved. The effect of this and other physical remediation techniques on the health of soil microbial communities has been poorly studied and indeed, largely ignored. This study reports the impact on soil microbial communities during the application of an electric field within ex situ laboratory soil microcosms contaminated with pentachlorophenol (PCP; 100 mg kg -1 oven dry soil). Electrokinetics reduced counts of culturable bacteria and fungi, soil microbial respiration and carbon substrate utilisation, especially close to the acidic anode where PCP accumulated (36 d), perhaps exacerbated by the greater toxicity of PCP at lower soil pH. There is little doubt that a better awareness of the interactions between soil electrokinetic processes and microbial communities is key to improving the efficacy and sustainability of this remediation strategy. - Electrokinetics negatively impacted soil

  16. IMPROVED RISK ASSESSMENT AND REMEDIATION OF SOIL METALS BASED ON BIOAVAILABILITY MEASUREMENTS

    Science.gov (United States)

    Heavy metals in soils can comprise risk through plant uptake or soil ingestion. Recent research results and progress in understandings of risks and methods for soil metal remediation will be presented. Beneficial use of composts/bosolids plus limestone to remediate metal killed e...

  17. Using biochar for remediation of soils contaminated with heavy metals and organic pollutants.

    Science.gov (United States)

    Zhang, Xiaokai; Wang, Hailong; He, Lizhi; Lu, Kouping; Sarmah, Ajit; Li, Jianwu; Bolan, Nanthi S; Pei, Jianchuan; Huang, Huagang

    2013-12-01

    Soil contamination with heavy metals and organic pollutants has increasingly become a serious global environmental issue in recent years. Considerable efforts have been made to remediate contaminated soils. Biochar has a large surface area, and high capacity to adsorb heavy metals and organic pollutants. Biochar can potentially be used to reduce the bioavailability and leachability of heavy metals and organic pollutants in soils through adsorption and other physicochemical reactions. Biochar is typically an alkaline material which can increase soil pH and contribute to stabilization of heavy metals. Application of biochar for remediation of contaminated soils may provide a new solution to the soil pollution problem. This paper provides an overview on the impact of biochar on the environmental fate and mobility of heavy metals and organic pollutants in contaminated soils and its implication for remediation of contaminated soils. Further research directions are identified to ensure a safe and sustainable use of biochar as a soil amendment for remediation of contaminated soils.

  18. Minimizing the Health Risks from Hydrocarbon Contaminated Soils by Using Electric Field-Based Treatment for Soil Remediation

    Directory of Open Access Journals (Sweden)

    Irina Aura Istrate

    2018-01-01

    Full Text Available The present work addresses the assessment of human health risk from soil contaminated with total petroleum hydrocarbons (TPHs due to crude oil pollution, with a particular focus on the polycyclic aromatic hydrocarbon (PAH group of carcinogenic and toxic substances. Given that the measured risk for human health exceeded the accepted level, the study considered an electrochemical remediation method. The laboratory-scale experiments were conducted by using an electric field-based treatment as a possible solution for the remediation of contaminated soil. After 20 days of treatment, while the voltage applied was 15 V (specific voltage of 1 V/cm, the hydrocarbon content was significantly reduced. The parameters measured to determine the overall remediation efficiency were pH, redox potential, ionic strength, soil characteristics, voltage gradient, and zeta potential. The remediation degree observed during the experiments was around 50% for TPHs and 46% for PAHs. The applied remediation method resulted in significant removal efficiency of the tested contaminants from the soil. Consequently, the human health risk assessment for the new degree of contaminants in the soil was achieved. This data demonstrated to what extent the application of the remediation applied technology ensured an acceptable risk under the same exposure conditions for the industrial workers.

  19. Remediation of soil contaminated with polycyclic aromatic ...

    African Journals Online (AJOL)

    user

    2011-02-14

    Feb 14, 2011 ... The aim of this study was to determine ways of remediating soils contaminated with polycyclic aromatic hydrocarbons (PAHs) associated with crude oil. The study involves the use of planted cowpeas, mushrooms, algae, dead vegetable and live earthworm, and fire-heating of the contaminated garden soil ...

  20. The harm of petroleum-polluted soil and its remediation research

    Science.gov (United States)

    Wang, Shuguang; Xu, Yan; Lin, Zhaofeng; Zhang, Jishi; Norbu, Namkha; Liu, Wei

    2017-08-01

    Land resources are the foundation of human's survival and development, and it's one of the most valuable natural resources of each country. In view of the serious problems of petroleum pollution to soil caused during the exploration and development processes, this article based on a large number of literature researches, firstly discussed the compositions and properties of petroleum contaminants, secondly investigated some restoration methods for the current situation of petroleum polluted soil, compared and analyzed the advantages and disadvantages of three kinds of bioremediation technologies. Finally, according to the deficiencies of previous research and existing problems, made an outlook of the physical and chemical remediation, bioremediation, and microbe-plant remediation, to provide some enlightenments for petroleum-contaminated soil remediation.

  1. Optimum Remediation Conditions of Vertical Electrokinetic-Flushing Equipment to Decontaminate a Radioactive Soil

    International Nuclear Information System (INIS)

    Kim, Gye Nam; Yang, Byeong IL; Moon, Jei Kwon; Lee, Kune Woo

    2009-01-01

    Vertical electrokintic-flushing remediation equipment was developed for the remediation of a radioactive soil near nuclear facilities. An optimum reagent was selected to decontaminate the radioactive soil near nuclear facilities with the developed vertical electrokintic-flushing remediation equipment, and the optimum remediation conditions were established to obtain a higher remediation efficiency. Namely, acetic acid was selected as an optimum reagent due to its higher remediation efficiency. When the electrokinetic remediation and the electrokinetic-flushing remediation results were compared, the removal efficiency of 4.6% and the soil waste solution volume of 1.5 times were increased in the electrokinetic remediation. When the potential gradient within an electrokinetic soil cell was increased by two times (4.0 V/cm), the removal efficiencies of Co 2+ and Cs + were increased by about 4.3%( Co 2+ : 98.9%, Cs + : 96.7%). Also, when the reagent concentration was increased from 0.01 M to 0.05 M, the removal efficiency of Co 2+ was increased but that of Cs + was decreased. Therefore, the optimum remediation conditions were that the acetic concentration was 0.01 M ∼ 0.05 M, the potential gradient was 4 V/cm, the injection of reagent 2.4 ml/g, and the remediation period was 20 days.

  2. Sequential Application of Soil Vapor Extraction and Bioremediation Processes for the Remediation of Ethylbenzene-Contaminated Soils

    DEFF Research Database (Denmark)

    Soares, António Carlos Alves; Pinho, Maria Teresa; Albergaria, José Tomás

    2012-01-01

    Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application of these technol......Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application...

  3. [Optimization of electrode configuration in soil electrokinetic remediation].

    Science.gov (United States)

    Liu, Fang; Fu, Rong-Bing; Xu, Zhen

    2015-02-01

    Electric field distributions of several different electrode configurations in non-uniform electric field were simulated using MATLAB software, and the electrokinetic remediation device was constructed according to the best electrode configuration. The changes of soil pH and heavy metal residues in different parts of the device during the electrokinetic remediation were also studied. The results showed that, in terms of the effectiveness of the electric field strength, the square (1-D-1) and hexagonal (2-D-3) were the optimal electrode configurations for one-dimensional and two-dimensional respectively and the changes of soil pH, the removal of heavy metals and the distribution of electric field were closely related to one another. An acidic migration band, which could prevent premature precipitation of heavy metals to a certain extent and promote electrokinetic removal of heavy metals, was formed gradually along with the remediation in the whole hexagon device when the cathodic pH was controlled during the remediation of the four cationic metallic ions, Cd2+, Ni2+, Pb2+ and Cu2+. After 480-hour remediation, the total removals of Cd, Ni, Pb and Cu were 86.6%, 86.2%, 67.7% and 73.0%, respectively. Remediation duration and replacement frequency of the electrodes could be adjusted according to the repair target.

  4. An analysis on the effect of the electrokinetic remediation of a soil around decommissioning site by reagent

    International Nuclear Information System (INIS)

    Kim, Gye-Nam; Jung, Yun-Ho; Lee, Jung-Joon; Moon, Jei-Kwon; Jung, Chong-Hun; Lee, Kune-Woo; Chung, Un-Soo

    2008-01-01

    Most nuclear facility sites have been contaminated by the leakage of a radioactive waste-solution due to the corrosion of concrete and pipes by a long-term operation of waste-solution tanks and connection pipes set up in an underground around nuclear power plant. Also, a great volume of radioactive soil has been generated due to the loss of radioactive contaminants during a long-term operation of nuclear facilities and nuclear operational accidents. Even if people's health has been threatened by a dissolution of radionuclide from such a contaminated soil, the existing soil remediation technologies have a lower removal efficiency for radionuclide. Therefore, it is necessary to develop a soil remediation technology suitable for the contamination characteristics of national nuclear facility sites

  5. Electrodialytic Remediation of Soil Slurry-Removal of Cu, Cr, and As

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Hansen, Henrik K.

    2009-01-01

    Severe soil contamination is often found at old wood preservation sites and a common combination of pollutants is Cu, Cr, and As. In the present work it is tested if simultaneous removal of Cu, Cr, and As can be obtained in an electrodialytic cell where the polluted soil is remediated as a stirred...... experiments; an experiment where the soil was suspended in distilled water and the remediation lasted 3 weeks with 2.5 mA and an experiment with acidification of the soil suspension with HNO3 to pH about 1.0 (2 weeks and 5 mA). The best separation of pollutants and soil was obtained in the experiment...... with suspension in distilled water. Based on soil concentrations, good Cu removal (95%) was obtained in both experiments. Removal of Cr was most efficient from the acidified soil suspension (74%). Both Cu and Cr concentrations were below the limiting values after the remediation. The As concentration, however...

  6. Remediation of contaminated soils by biotechnology with nanomaterials: bio-behavior, applications, and perspectives.

    Science.gov (United States)

    Gong, Xiaomin; Huang, Danlian; Liu, Yunguo; Peng, Zhiwei; Zeng, Guangming; Xu, Piao; Cheng, Min; Wang, Rongzhong; Wan, Jia

    2018-05-01

    Soil contamination caused by heavy metals and organic pollutants has drawn world-wide concern. Biotechnology has been applied for many years to the decontamination of soils polluted with organic and inorganic contaminants, and novel nanomaterials (NMs) has attracted much concern due to their high capacity for the removal/stabilization/degradation of pollutants. Recently, developing advanced biotechnology with NMs for the remediation of contaminated soils has become a hot research topic. Some researchers found that bioremediation efficiency of contaminated soils was enhanced by the addition of NMs, while others demonstrated that the toxicity of NMs to the organism negatively influenced the repair capacity of polluted soils. This paper reviews the application of biotechnology and NMs in soil remediation, and further provides a critical view of the effects of NMs on the phytoremediation and micro-remediation of contaminated soils. This review also discusses the future research needs for the combined application of biotechnology and NMs in soil remediation.

  7. Chemical and bioanalytical characterisation of PAHs in risk assessment of remediated PAH-contaminated soils.

    Science.gov (United States)

    Larsson, Maria; Hagberg, Jessika; Rotander, Anna; van Bavel, Bert; Engwall, Magnus

    2013-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in soil at former industrial areas; and in Sweden, some of the most contaminated sites are being remediated. Generic guideline values for soil use after so-called successful remediation actions of PAH-contaminated soil are based on the 16 EPA priority pollutants, which only constitute a small part of the complex cocktail of toxicants in many contaminated soils. The aim of the study was to elucidate if the actual toxicological risks of soil samples from successful remediation projects could be reflected by chemical determination of these PAHs. We compared chemical analysis (GC-MS) and bioassay analysis (H4IIE-luc) of a number of remediated PAH-contaminated soils. The H4IIE-luc bioassay is an aryl hydrocarbon (Ah) receptor-based assay that detects compounds that activate the Ah receptor, one important mechanism for PAH toxicity. Comparison of the results showed that the bioassay-determined toxicity in the remediated soil samples could only be explained to a minor extent by the concentrations of the 16 priority PAHs. The current risk assessment method for PAH-contaminated soil in use in Sweden along with other countries, based on chemical analysis of selected PAHs, is missing toxicologically relevant PAHs and other similar substances. It is therefore reasonable to include bioassays in risk assessment and in the classification of remediated PAH-contaminated soils. This could minimise environmental and human health risks and enable greater safety in subsequent reuse of remediated soils.

  8. Evaluation of bio-remediation technologies for PAHs contaminated soils

    International Nuclear Information System (INIS)

    Garcia Frutos, F.J.; Diaz, J.; Rodriguez, V.; Escolano, O.; Garcia, S.; Perez, R.; Martinez, R.; Oromendia, R.

    2005-01-01

    Natural attenuation is a new concept related to polluted soil remediation. Can be understood like an 'in situ' bio-remediation process with low technical intervention. This low intervention may be in order to follow the behaviour of pollutants 'monitored natural attenuation' or include an optimisation process to improve biological remediation. The use of this technology is a fact for light hydrocarbon polluted soil, but few is known about the behaviour of polycyclic aromatic hydrocarbons (PAHs) in this process. PAHs are more recalcitrant to bio-remediation due to their physic-chemical characteristics, mainly hydrophobicity and electrochemical stability. PAHs are a kind of pollutants widely distributed in the environment, not only in the proximity of the source. This linked to the characteristics of some of them related to toxicity and mutagenicity implies its inclusion as target compounds from an environmental point of view. Their low availability, solubility and the strong tendency to bind to soil particle, especially to the organic phase affect PAHs biological mineralisation. So, if the pollutant is not available to microorganisms it can not be bio-degraded. Bioavailability can be assessed form several but complementary points of view: physico-chemical and biological. First including the term availability and the second to point out the capacity of soil microorganisms to mineralize PAHs. Availability and Bio-degradability must be determined, as well as the presence and activity of specific degraders among the soil organisms, once settled these points is necessary to study the biological requirements to optimise biodegradation kinetics of these compounds. In this work we present a study carried out on a soil, contaminated by PAHs, the study includes three main topics: bioavailability assessment (both term availability and bio-degradability), bio-remediation assessment, once optimised conditions for natural attenuation and finally a simulation of the

  9. Complying with Land Disposal Restrictions (LDR) for CERCLA remedial actions involving contaminated soil and debris

    International Nuclear Information System (INIS)

    Bascietto, J.

    1991-01-01

    CERCLA Sect. 121(e) requires that remedial actions must comply with at least the minimum standards of all ''applicable or relevant and appropriate requirements'' (ARARs) of federal and state laws. EPA has determined that RCRA land disposal restrictions may be ARAR for certain CERCLA remedial actions involving soil and debris. This means that soil and debris contaminated with prohibited or restricted wastes cannot be land disposed if (1) these wastes have not attained the treatment standards set by EPA for a specified waste or (2) have been the subject of a case-by-case extension, national capacity variance, or successful ''no migration'' petition. RCRA LDR treatment standards are based on ''Best Demonstrated Available Technology'' (BDAT), not on health-based concentrations. Because the treatment of the soil and debris matrix presents technological difficulties not yet addressed by EPA (BDAT standards are generally set for industrial process wastes), compliance options such as obtaining a Treatability Variance, are available and will generally be necessary for soil and debris wastes. In the recently promulgated revisions to the National Contingency Plan (NCP) for CERCLA implementation, EPA provides important information for CERCLA project managers regarding LDR compliance, particularly for obtaining a treatability variance for land disposal of contaminated soil and debris

  10. Biofuel or excavation? - Life cycle assessment (LCA) of soil remediation options

    Energy Technology Data Exchange (ETDEWEB)

    Suer, Pascal; Andersson-Skoeld, Yvonne [Swedish Geotechnical Institute, 58193 Linkoeping (Sweden)

    2011-02-15

    The environmental consequences of soil remediation through biofuel or through dig-and-dump were compared using life cycle assessment (LCA). Willow (Salix viminalis) was actually grown in-situ on a discontinued oil depot, as a phytoremediation treatment. These data were used for the biofuel remediation, while excavation-and-refill data were estimated from experience. The biofuel remediation had great environmental advantages compared to the ex situ excavation remediation. With the ReCiPe impact assessment method, which included biodiversity, the net environmental effect was even positive, in spite of the fact that the wood harvest was not utilised for biofuel production, but left on the contaminated site. Impact from the Salix viminalis cultivation was mainly through land use for the short rotation coppice, and through journeys of control personnel. The latter may be reduced when familiarity with biofuel as a soil treatment method increases. The excavation-and-refill remediation was dominated by the landfill and the transport of contaminated soil and backfill. (author)

  11. Remediation Of Radioactive Contaminated Soil in Oil Fields

    International Nuclear Information System (INIS)

    Taha, A.A.; Hassib, G.M.; Ibrahim, Z.A.

    2011-01-01

    Radioactive contamination by naturally occurring radioactive materials (NORM) in evaporation pond has been evaluated. At several onshore oil field locations, the produced water is discharged to form artificial lagoons or ponds. Subsequently, the released waters drain to the ground leaving radioactive deposits associated with the soil that eventually require remedial action in accordance with radiation protection principles. The present study aims to investigate the remediation of contaminated soil in some oil fields and in this concern, two scenarios were proposed. The first scenario is studying the feasibility of using soil washing technique (a physical-chemical separation process) for removing radium-226 from the contaminated soil samples collected from an evaporating pond. The size/activity distribution analyses were carried out. The data obtained showed that almost 68 % of the investigated soil was coarse sand (≥ 300 μm), 28 % was medium and fine sand (≤300 μm and (≥75 μm) and only small fraction of 4 % was silt and clay (≤75 μm). A series of mild acids such as HCl and mild NaCl/HCl (chloride washing) were used for washing the investigated soil fractions. The obtained data showed that the coarse fraction ≥ 300 μm can be re mediated below a regulatory level of 1Bq/g. and the radium from this coarse fraction could be easily removed by screening and chloride washing. For the remediation of (≤ 300 μm and (≥ 75 μm soil fractions, a series of mild chloride washing experiments also showed that the chloride base (NaCl/HCl) was found to be potentially useful. However, there was a difficulty in achieving a low radium value in the fine (≥ 75 μm size fractions using chloride washing. The second scenario is to get rid of all contaminated soil and store it in a concrete basin through the program of radiological protection of personnel and environment. Preliminary gamma survey of contaminated soil showed that the significant area of the investigated

  12. Soil bacteria for remediation of polluted soils

    Energy Technology Data Exchange (ETDEWEB)

    Springael, D; Bastiaens, L; Carpels, M; Mergaey, M; Diels, L

    1996-09-18

    Soil bacteria, specifically adapted to contaminated soils, may be used for the remediation of polluted soils. The Flemish research institute VITO has established a collection of bacteria, which were isolated from contaminated areas. This collection includes microbacteria degrading mineral oils (Pseudomonas sp., Acinetobacter sp. and others), microbacteria degrading polycyclic aromatic hydrocarbons (genera Sphingomonas and Mycobacterium), microbacteria degrading polychlorobiphenyls (genus Ralstonia and strains related to beta-Proteobacteria), and metal resistant bacteria with plasmid borne resistances to Cd, Zn, Ni, Co, Cu, Hg, and Cr. Bench-scale reactors were developed to investigate the industrial feasibility of bioremediation. Batch Stirred Tank Reactors were used to evaluate the efficiency of oil degraders. Soils, contaminated with non-ferrous metals, were treated using a Bacterial Metal Slurry Reactor. It was found that the reduction of the Cd concentration may vary strongly from sample to sample: reduction factors vary from 95 to 50%. Is was shown that Cd contained in metallic sinter and biologically unavailable Cd could not be removed.

  13. An analysis on remediation characteristics of soils contaminated with Co for in-situ application

    International Nuclear Information System (INIS)

    Kim, K. N.; Won, H. J.; Kweun, H. S.; Shon, J. S.; Oh, W. J.

    1999-01-01

    The solvent flushing apparatus for in-situ soil remediation was designed. After the soil around nuclear facilities was sampled and compulsorily contaminated by Co solution, the remediation characteristics by solvent flushing were analyzed. Meanwhile, the nonequilibrium sorption code was developed for modelling of the soil remediation by solvent flushing, and input parameters needed for modelling were measured by laboratory experiment. Experimental results are as follows: The soil around nuclear facilities belongs to Silt Loam including a lot of silt and sand. When water was used as a solvent, the higher was the hydraulic conductivity, the higher the efficiency of soil remediation was. The values calculated by the nonequilibrium sorption code agreed with experimental values more exactly than the values calculated by the equilibrium sorption code. When citric acid was used as a solvent, the soil remediation efficiency by citric acid showed 1.65 times that by water

  14. ELECTROKINETIC REMEDIATION STUDY FOR CADMIUM CONTAMINATED SOIL

    OpenAIRE

    P. Bala Ramudu; R. P. Tiwari; R. K. Srivastava

    2007-01-01

    This paper presents the results of an experimental research undertaken to evaluate different purging solutions to enhance the removal of cadmium from spiked contaminated field soil by electrokinetic remediation. Three experiments were conducted when soil was saturated with deionised water and subsequently deionised water, ammonium citrate and sodium citrate were used as purging solutions at anode end. One experiment was conducted when the soil was saturated with ammonium citrate and itself wa...

  15. Electrical Resistance and Transport Numbers of Ion-Exchange Membranes Used in Electrodialytic Soil Remediation

    DEFF Research Database (Denmark)

    Hansen, Henrik; Ottosen, Lisbeth M.; Villumsen, Arne

    1999-01-01

    Electrodialytic soil remediation is a recently developed method to decontaminate heavy metal polluted soil using ion-exchange membranes. In this method one side of the ion-exchange membrane is in direct contact with the polluted soil. It is of great importance to know if this contact with the soil...... different electrodialytic soil remediation experiments. The experiments showed that after the use in electrodialytic soil remediation, the ion-exchange membranes had transport numbers in the same magnitude as new membranes. The electrical resistance for six membranes did not differ from that of new...

  16. Review of the Vortec soil remediation demonstration program

    International Nuclear Information System (INIS)

    Patten, J.S.

    1994-01-01

    The principal objective of the METC/Vortec program is to develop and demonstrate the effectiveness of the Vortec CMS in remediating soils contaminated with hazardous materials and/or low levels of radionuclides. To convincingly demonstrate the CMS's capability, a Demonstration Plant will be constructed and operated at a DOE site that has a need for the remediation of contamination soil. The following objectives will be met during the program: (1) establish the glass chemistry requirements to achieve vitrification of contaminated soils found at the selected DOE site; (2) complete the design of a fully integrated soil vitrification demonstration plant with a capacity to process 25 TPD of soil; (3) establish the cost of a fully integrated soil demonstration plant with a capacity to process 25 TPD of soil; (4) construct and operate a fully integrated demonstration plant; (5) analyze all influent and effluent streams to establish the partitioning of contaminants and to demonstrate compliance with all applicable health, safety, and environmental requirements; (6) demonstrate that the CMS technology has the capability to produce a vitrified product that will immobilize the hazardous and radionuclide materials consistent with the needs of the specific DOE waste repositories

  17. Effects of Soil Oxygen Conditions and Soil pH on Remediation of DDT-contaminated Soil by Laccase from White Rot Fungi

    Directory of Open Access Journals (Sweden)

    Yuechun Zhao

    2010-04-01

    Full Text Available High residues of DDT in agricultural soils are of concern because they present serious threats to food security and human health. This article focuses on remediation of DDT-contaminated soil using laccase under different soil oxygen and soil pH conditions. The laboratory experiment results showed significant effects of soil oxygen conditions and soil pH on remediation of DDT-contaminated soil by laccase at the end of a 25-d incubation period. This study found the positive correlation between the concentration of oxygen in soil and the degradation of DDT by laccase. The residue of DDTs in soil under the atmosphere of oxygen decreased by 28.1% compared with the atmosphere of nitrogen at the end of the incubation with laccase. A similar pattern was observed in the remediation of DDT-contaminated soil by laccase under different flooding conditions, the higher the concentrations of oxygen in soil, the lower the residues of four DDT components and DDTs in soils. The residue of DDTs in the nonflooding soil declined by 16.7% compared to the flooded soil at the end of the incubation. The residues of DDTs in soils treated with laccase were lower in the pH range 2.5–4.5.

  18. Technology selection for remediation of lead and hydrocarbon contaminated soil

    International Nuclear Information System (INIS)

    Richardson, K.E.; Sparks, G.M.

    1993-01-01

    This paper presents a methodology for selection of a technology for remediation of 70,000 tons of lead and hydrocarbon impacted soil resulting from an excavation at the Mobil Torrance Refinery. This methodology resulted from over two years of extensive research and technology evaluation. Twelve technologies and combination of technologies were evaluated, which often included bench scale testing, to determine the most cost effective and technically feasible remediation option. The results of the studies for each technology are discussed and presented in tabular form. The technologies investigated include: fixation/stabilization, soil washing, solvent washing, heap leach extraction, froth flotation, bioremediation, thermal desorption, electrokinetic extraction, asphalt incorporation, vitrification, off-site treatment, and off-site disposal. The associated costs and technical feasibility of each of the remediation options evaluated are presented. Laboratory analyses of the excavated soil indicate hydrocarbons range from non-detect to 11,000 ppm with an average of 2,600 ppm, soluble lead (CA test-not TCLP) range from 1.4 ppm to 100 ppm with an average of 29 ppm, and low levels of organic lead are present. Average grain size of the soil ranges from number-sign 200 to number-sign 120 mesh, and permeability averages 10--4 cm/sec. Significant odors, likely caused by hydrogen sulfide and thiophenes, were detected when the soil was excavated and control of odors during the remediation phase is a critical concern

  19. Thermal remediation of tar-contaminated soil and oil-contaminated gravel

    International Nuclear Information System (INIS)

    Anthony, E.J.; Wang, J.

    2005-01-01

    High temperature treatments are commonly considered for the decontamination of soil as they have the advantages of reliability, high capacity, and effective destruction of hazardous materials with reduced long-term liability. This paper examined the remediation of soil contaminated by coal tar as well as gravel contaminated by oil. Pilot plant studies were conducted using 2 representative incineration technologies: rotary kiln and fluidized bed. The coal tar contaminated soil had accumulated over a few decades at a calcination plant in western Canada. The soil was sticky and could not be handled by conventional feeding and combustion systems. Crushed lignite was mixed with the soil as an auxiliary fuel and to reduce stickiness. A pilot plant furnace was used to evaluate the potential of decontamination in a rotary calciner. An analysis of both a modelling study and the test results showed that complete decontamination could be achieved in the targeted calciner. The results suggested that energy recovery was also possible, which could in turn make the remediation process more cost-effective. Decontamination of oil-contaminated gravel was conducted with a pilot plant fluidized bed combustor to study the feasibility of using incineration technology in the remediation of gravel and debris contaminated by oil spills. Results indicated that the gravel was decontaminated with acceptable emission performance. It was concluded that the study will be valuable to the application of commercial incineration processes for the remediation of polluted soils. It was observed that the weathering of the oiled gravel lowered the rate of decontamination. A small amount of salt water resulted in lowered decontamination rates, which may be an important factor for situations involving the remediation of shoreline gravel contaminated by oil. 24 refs., 6 tabs., 7 figs

  20. Enhancement of in situ Remediation of Hydrocarbon Contaminated Soil

    Energy Technology Data Exchange (ETDEWEB)

    Palmroth, M.

    2006-07-01

    Approximately 750 000 sites of contaminated land exist across Europe. The harmful chemicals found in Finnish soils include heavy metals, oil products, polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorophenols, and pesticides. Petroleum and petroleum products enter soil from ruptured oil pipelines, land disposal of refinery products, leaking storage tanks and through accidents. PAH contamination is caused by the spills of coal tar and creosote from coal gasification and wood treatment sites in addition to oil spills. Cleanup of soil by bioremediation is cheaper than by chemical and physical processes. However, the cleaning capacity of natural attenuation and in situ bioremediation is limited. The purpose of this thesis was to find feasible options to enhance in situ remediation of hydrocarbon contaminants. The aims were to increase the bioavailability of the contaminants and microbial activity at the subsurface in order to achieve higher contaminant removal efficiency than by intrinsic biodegradation alone. Enhancement of microbial activity and decrease of soil toxicity during remediation were estimated by using several biological assays. The performance of these assays was compared in order to find suitable indicators to follow the progress of remediation. Phytoremediation and chemical oxidation are promising in situ techniques to increase the degradation of hydrocarbons in soil. Phytoremediation is plant-enhanced decontamination of soil and water. Degradation of hydrocarbons is enhanced in the root zone by increased microbial activity and through the detoxifying enzymes of plants themselves. Chemical oxidation of contaminants by Fenton's reaction can produce degradation products which are more biodegradable than the parent compounds. Fenton's reaction and its modifications apply solutions of hydrogen peroxide and iron for the oxidation of organic chemicals. The cost of oxidation can be reduced by aiming at partial instead of full

  1. Bioavailability enhanced rhizosphere remediation of petroleum hydrocarbon contaminated soil

    International Nuclear Information System (INIS)

    Marchenko, A.; Vorobyov, A.; Zharikov, G.; Ermolenko, Z.; Dyadishchev, N.; Borovick, R.; Sokolov, M.; Ortega-Calvo, J.J.

    2005-01-01

    Aliphatic, aromatic and polycyclic aromatic oil hydrocarbons are structurally complicated man-caused pollutants that are constantly brought into biosphere. Oil production in Russia, so as all over the world, is connected with pollution of biotopes, ecosystems and agro-landscapes. Presently large funds are allocated either for oil leak prevention or for discharged oil gathering. At the same time, in spite of large necessity in technologies for efficient reconstruction of soil bio-productivity, reliable regional systems of their remediation in situ have not been developed yet. One such method is rhizosphere remediation, a biotechnology, based on the functioning of plant-microbial complexes. Little is known about bioavailability in phyto-remediation systems. Specific bioavailability-promoting mechanisms, operating in soil with hydrocarbon-degrading populations, may be responsible for increased rates of pollutant transformation (increased bacterial adherence to the pollutants, production of bio-surfactants by bacteria or by plants, possible role of chemotaxis). In the course of work collection of 42 chemo-tactically active bio-surfactant producing strain-degraders of petroleum hydrocarbons including polycyclic aromatic hydrocarbons (PAHs) was created. Two representative strains were selected for detailed chemotaxis studies with PAHs (naphthalene, phenanthrene, anthracene, and pyrene), bacterial lipopolysaccharide and root exudates from seven different plants. These strains are produce the bio-surfactants (rhamno-lipid). The chemotactic response was quantified with a capillary and densitometric chemotaxis assay. Surface tension of cultural liquid was measured after cultivation of strains in the presence of hexadecane or phenanthrene with the use of a ring tensiometer. Before measuring of surface tension microbial cells were collected from liquid culture by centrifugation. Total petroleum Hydrocarbons (TPH) in soil were analyzed by infra-red spectroscopy method. PAHs

  2. Bioavailability enhanced rhizosphere remediation of petroleum hydrocarbon contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Marchenko, A.; Vorobyov, A.; Zharikov, G.; Ermolenko, Z.; Dyadishchev, N.; Borovick, R.; Sokolov, M. [Research Centre for Toxicology and Hygienic Regulation of Biopreparations, Moscow region (Russian Federation); Ortega-Calvo, J.J. [Instituto de Recursos Naturales y Agrobiologia, CSIC, Sevilla (Spain)

    2005-07-01

    Aliphatic, aromatic and polycyclic aromatic oil hydrocarbons are structurally complicated man-caused pollutants that are constantly brought into biosphere. Oil production in Russia, so as all over the world, is connected with pollution of biotopes, ecosystems and agro-landscapes. Presently large funds are allocated either for oil leak prevention or for discharged oil gathering. At the same time, in spite of large necessity in technologies for efficient reconstruction of soil bio-productivity, reliable regional systems of their remediation in situ have not been developed yet. One such method is rhizosphere remediation, a biotechnology, based on the functioning of plant-microbial complexes. Little is known about bioavailability in phyto-remediation systems. Specific bioavailability-promoting mechanisms, operating in soil with hydrocarbon-degrading populations, may be responsible for increased rates of pollutant transformation (increased bacterial adherence to the pollutants, production of bio-surfactants by bacteria or by plants, possible role of chemotaxis). In the course of work collection of 42 chemo-tactically active bio-surfactant producing strain-degraders of petroleum hydrocarbons including polycyclic aromatic hydrocarbons (PAHs) was created. Two representative strains were selected for detailed chemotaxis studies with PAHs (naphthalene, phenanthrene, anthracene, and pyrene), bacterial lipopolysaccharide and root exudates from seven different plants. These strains are produce the bio-surfactants (rhamno-lipid). The chemotactic response was quantified with a capillary and densitometric chemotaxis assay. Surface tension of cultural liquid was measured after cultivation of strains in the presence of hexadecane or phenanthrene with the use of a ring tensiometer. Before measuring of surface tension microbial cells were collected from liquid culture by centrifugation. Total petroleum Hydrocarbons (TPH) in soil were analyzed by infra-red spectroscopy method. PAHs

  3. An evaluation of different soil washing solutions for remediating arsenic-contaminated soils.

    Science.gov (United States)

    Wang, Yiwen; Ma, Fujun; Zhang, Qian; Peng, Changsheng; Wu, Bin; Li, Fasheng; Gu, Qingbao

    2017-04-01

    Soil washing is a promising way to remediate arsenic-contaminated soils. Most research has mostly focused on seeking efficient extractants for removing arsenic, but not concerned with any changes in soil properties when using this technique. In this study, the removal of arsenic from a heavily contaminated soil employing different washing solutions including H 3 PO 4 , NaOH and dithionite in EDTA was conducted. Subsequently, the changes in soil physicochemical properties and phytotoxicity of each washing technique were evaluated. After washing with 2 M H 3 PO 4 , 2 M NaOH or 0.1 M dithionite in 0.1 M EDTA, the soil samples' arsenic content met the clean-up levels stipulated in China's environmental regulations. H 3 PO 4 washing decreased soil pH, Ca, Mg, Al, Fe, and Mn concentrations but increased TN and TP contents. NaOH washing increased soil pH but decreased soil TOC, TN and TP contents. Dithionite in EDTA washing reduced soil TOC, Ca, Mg, Al, Fe, Mn and TP contents. A drastic color change was observed when the soil sample was washed with H 3 PO 4 or 0.1 M dithionite in 0.1 M EDTA. After adjusting the soil pH to neutral, wheat planted in the soil sample washed by NaOH evidenced the best growth of all three treated soil samples. These results will help with selecting the best washing solution when remediating arsenic-contaminated soils in future engineering applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. On site remediation of a fuel spill and soil reuse in Antarctica.

    Science.gov (United States)

    McWatters, R S; Wilkins, D; Spedding, T; Hince, G; Raymond, B; Lagerewskij, G; Terry, D; Wise, L; Snape, I

    2016-11-15

    The first large-scale remediation of fuel contamination in Antarctica treated 10000L of diesel dispersed in 1700t of soil, and demonstrated the efficacy of on-site bioremediation. The project progressed through initial site assessment and natural attenuation, passive groundwater management, then active remediation and the managed reuse of soil. Monitoring natural attenuation for the first 12years showed contaminant levels in surface soil remained elevated, averaging 5000mg/kg. By contrast, in five years of active remediation (excavation and biopile treatment) contaminant levels decreased by a factor of four. Chemical indicators showed hydrocarbon loss was apportioned to both biodegradation and evaporative processes. Hydrocarbon degradation rates were assessed against biopile soil temperatures, showing a phase of rapid degradation (first 100days above soil temperature threshold of 0°C) followed by slower degradation (beyond 100days above threshold). The biopiles operated successfully within constraints typical of harsh climates and remote sites, including limitations on resources, no external energy inputs and short field seasons. Non-native microorganisms (e.g. inoculations) and other organic materials (e.g. bulking agents) are prohibited in Antarctica making this cold region more challenging for remediation than the Arctic. Biopile operations included an initial fertiliser application, biannual mechanical turning of the soil and minimal leachate recirculation. The biopiles are a practical approach to remediate large quantities of contaminated soil in the Antarctic and already 370t have been reused in a building foundation. The findings presented demonstrate that bioremediation is a viable strategy for Antarctica and other cold regions. Operators can potentially use the modelled relationship between days above 0°C (threshold temperature) and the change in degradation rates to estimate how long it would take to remediate other sites using the biopile technology

  5. Degradation of oil products in a soil from a Russian Barents hot-spot during electrodialytic remediation

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Lejon, Tore; Jensen, Pernille Erland

    2016-01-01

    A highly oil-polluted soil from Krasnoe in North-West Russia was used to investigate the degradation of organic pollutants during electrodialytic remediation. Removal efficiencies were up to 70 % for total hydrocarbons (THC) and up to 65 % for polyaromatic hydrocarbons (PAH). Relatively more...... of the lighter PAH compounds and THC fractions were degraded. A principal component analysis (PCA) revealed a difference in the distribution of PAH compounds after the remediation. The observed clustering of experiments in the PCA scores plot was assessed to be related to the stirring rate. Multivariate analysis...... of the experimental settings and final concentrations in the 12 experiments revealed that the stirring rate of the soil suspension was by far the most important parameter for the remediation for both THC and PAH. Light was the second most important variable for PAH and seems to influence degradation. The experimental...

  6. Remediation of Cd-contaminated soil around metal sulfide mines

    Science.gov (United States)

    Lu, Xinzhe; Hu, Xuefeng; Kang, Zhanjun; Luo, Fan

    2017-04-01

    The mines of metal sulfides are widely distributed in the southwestern part of Zhejiang Province, Southeast China. The activities of mining, however, often lead to the severe pollution of heavy metals in soils, especially Cd contamination. According to our field investigations, the spatial distribution of Cd-contaminated soils is highly consistent with the presence of metal sulfide mines in the areas, further proving that the mining activities are responsible for Cd accumulation in the soils. To study the remediation of Cd-contaminated soils, a paddy field nearby large sulfide mines, with soil pH 6 and Cd more than 1.56 mg kg-1, five times higher than the national recommended threshold, was selected. Plastic boards were deeply inserted into soil to separate the field and make experimental plots, with each plot being 4 m×4 m. Six treatments, TK01˜TK06, were designed to study the effects of different experimental materials on remediating Cd-contaminated soils. The treatment of TK01 was the addition of 100 kg zeolites to the plot; TK02, 100 kg apatites; TK03, 100 kg humid manure; TK04, 50 kg zeolites + 50 kg apatites; TK05, 50 kg zeolites + 50 kg humid manure; TK06 was blank control (CK). One month after the treatments, soil samples at the plots were collected to study the possible change of chemical forms of Cd in the soils. The results indicated that these treatments reduced the content of available Cd in the soils effectively, by a decreasing sequence of TK04 (33%) > TK02 (25%) > TK01 (23%) > TK05 (22%) > TK03 (15%), on the basis of CK. Correspondingly, the treatments also reduced the content of Cd in rice grains significantly, by a similar decreasing sequence of TK04 (83%) > TK02 (77%) > TK05 (63%) > TK01 (47%) > TK03 (27%). The content of Cd in the rice grains was 0.071 mg kg-1, 0.094 mg kg-1, 0.159 mg kg-1, 0.22 mg kg-1 and 0.306 mg kg-1, respectively, compared with CK, 0.418 mg kg-1. This experiment suggested that the reduction of available Cd in the soils is

  7. In situ soil remediation using electrokinetics

    International Nuclear Information System (INIS)

    Buehler, M.F.; Surma, J.E.; Virden, J.W.

    1994-11-01

    Electrokinetics is emerging as a promising technology for in situ soil remediation. This technique is especially attractive for Superfund sites and government operations which contain large volumes of contaminated soil. The approach uses an applied electric field to induce transport of both radioactive and hazardous waste ions in soil. The transport mechanisms include electroosmosis, electromigration, and electrophoresis. The feasibility of using electrokinetics to move radioactive 137 Cs and 60 Co at the Hanford Site in Richland, Washington, is discussed. A closed cell is used to provide in situ measurements of 137 Cs and 60 Co movement in Hanford soil. Preliminary results of ionic movement, along with the corresponding current response, are presented

  8. Remediation mechanisms for Cd-contaminated soil using natural sepiolite at the field scale.

    Science.gov (United States)

    Yin, Xiuling; Xu, Yingming; Huang, Rong; Huang, Qingqing; Xie, Zhonglei; Cai, Yanming; Liang, Xuefeng

    2017-12-13

    Remediation of heavy metal polluted agricultural soil is essential for human health and ecological safety and remediation mechanisms at the microscopic level are vital for their large-scale utilization. In this study, natural sepiolite was employed as an immobilization agent for in situ field-scale remediation of Cd-contaminated paddy soil and the remediation mechanisms were investigated in terms of soil chemistry and plant physiology. Natural sepiolite had a significant immobilization effect for bioavailable Cd contents in paddy soil, and consequently could lower the Cd concentrations of brown rice, husk, straw, and roots of rice plants by 54.7-73.7%, 44.0-62.5%, 26.5-67.2%, and 36.7-46.7%, respectively. Regarding soil chemistry, natural sepiolite increased the soil pH values and shifted the zeta potentials of soil particles to be more negative, enhancing the fixation or sorption of Cd on soil particles, and resulted in the reduction of HCl and DTPA extractable Cd concentrations in paddy soil. Natural sepiolite neither enhanced nor inhibited iron plaques on the rice root surface, but did change the chemical environments of Fe and S in rice root. Natural sepiolite improved the activities of antioxidant enzymes and enhanced the total antioxidant capacity to alleviate the stress of Cd. It also promotes the synthesis of GSH and NPT to complete the detoxification. In general, the remediation mechanisms of natural sepiolite for the Cd pollutant in paddy soil could be summarized as the collective effects of soil chemistry and plant physiology.

  9. Remediation of mercury-polluted soils using artificial wetlands.

    Science.gov (United States)

    García-Mercadoa, Héctor Daniel; Fernándezb, Georgina; Garzón-Zúñigac, Marco Antonio; Durán-Domínguez-de-Bazúaa, María Del Carmen

    2017-01-02

    Mexico's mercury mining industry is important for economic development, but has unfortunately contaminated soils due to open-air disposal. This case was seen at two sites in the municipality of Pinal de Amoles, State of Queretaro, Mexico. This paper presents an evaluation of mercury dynamics and biogeochemistry in two soils (mining waste soil) using ex-situ wetlands over 36 weeks. In soils sampled in two former mines of Pinal de Amoles, initial mercury concentrations were 424 ± 29 and 433 ± 12 mg kg -1 in La Lorena and San Jose, former mines, respectively. Typha latifolia and Phragmites australis were used and 20 reactors were constructed (with and without plants). The reactors were weekly amended with a nutrient solution (NPK), for each plant, at a pH of 5.0. For remediation using soils from San Jose 70-78% of mercury was removed in T. latifolia reactors and 76-82% in P. australis reactors, and for remediation of soils from La Lorena, mercury content was reduced by 55-71% using T. latifolia and 58-66% in P. australis reactors. Mercury emissions into the atmosphere were estimated to be 2-4 mg m -2 h -1 for both soils.

  10. Remediation of lead and cadmium-contaminated soils.

    Science.gov (United States)

    Salama, Ahmed K; Osman, Khaled A; Gouda, Neama Abdel-Razeek

    2016-01-01

    The research was designated to study the ability of plants to bio-accumulate, translocate and remove the heavy metals, lead and cadmium from contaminated soil. The herbal plant ryegrass, Lolium multiflorum was investigated as a bio-accumulator plant for these metals. The translocation of these heavy metals in the herbal plant was compared considering root to shoot transport and redistribution of metals in the root and shoot system. The trace metal contents from root and shoot parts were determined using atomic absorption spectrometer. The results showed that the percent of lead and cadmium transferred to ryegrass plant were averaged as 51.39, and 74.57%, respectively, while those remained in the soil were averaged as 48.61 and 25.43% following 60 days of treatment. The soil-plant transfer index in root and shoot system of ryegrass was found to be 0.32 and 0.20 for lead, and 0.50 and 0.25 for cadmium. These findings indicated that the herbal plant ryegrass, Lolium multiflorum is a good accumulator for cadmium than lead. The soil-plant transfer factor (the conc. of heavy metal in plant to the conc. in soil) indicated that the mechanism of soil remedy using the investigated plant is phytoextraction where the amounts of heavy metals transferred by plant roots into the above ground portions were higher than that remained in the soil. The method offers green technology solution for the contamination problem since it is effective technology with minimal impact on the environment and can be easily used for soil remedy.

  11. Integrated vacuum extraction/pneumatic soil fracturing system for remediation of low permeability soil

    International Nuclear Information System (INIS)

    Plaines, A.L.; Piniewski, R.J.; Yarbrough, G.D.

    1994-01-01

    There is wide use of vacuum extraction to remove volatile and semi-volatile organic compounds (VOCs) from unsaturated soil. At sites with soil of low permeability, VOC extraction rates may not be sufficient to meet soil clean-up objectives within the desired time frame. During vacuum extraction in low permeability soil, the diffusion rates of VOCs through the soil matrix may limit VOC removal rates. An increase in the number of subsurface paths for advective flow through the contaminated zone results in a larger mass of contaminant being removed in a shorter time frame, accelerating site remediation. One technique for increasing the number of subsurface flow paths is Terra Vac's process of pneumatic soil fracturing (PSF). In this process, pressurized air is injected into the subsurface, creating micro-fractures for the vacuum extraction system to withdraw contaminants. Similar to hydraulic fracturing techniques long used in the petroleum industry for increasing yield from oil and gas production wells, this technique has applications for soil remediation in low permeability conditions. Two case studies, one in Louisiana at a gasoline service station and one at a manufacturing plant in New York, are presented

  12. A comprehensive guide of remediation technologies for oil contaminated soil - Present works and future directions.

    Science.gov (United States)

    Lim, Mee Wei; Lau, Ee Von; Poh, Phaik Eong

    2016-08-15

    Oil spills result in negative impacts on the environment, economy and society. Due to tidal and waves actions, the oil spillage affects the shorelines by adhering to the soil, making it difficult for immediate cleaning of the soil. As shoreline clean-up is the most costly component of a response operation, there is a need for effective oil remediation technologies. This paper provides a review on the remediation technologies for soil contaminated with various types of oil, including diesel, crude oil, petroleum, lubricating oil, bitumen and bunker oil. The methods discussed include solvent extraction, bioremediation, phytoremediation, chemical oxidation, electrokinetic remediation, thermal technologies, ultrasonication, flotation and integrated remediation technologies. Each of these technologies was discussed, and associated with their advantages, disadvantages, advancements and future work in detail. Nonetheless, it is important to note that no single remediation technology is considered the best solution for the remediation of oil contaminated soil. This review provides a comprehensive literature on the various remediation technologies studied in the removal of different oil types from soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Phyto-remediation of contaminated soils; La phytoremediation des sols contamines

    Energy Technology Data Exchange (ETDEWEB)

    Morel, J.L. [Ecole Nationale Superieure Agronomie et des Industries Alimentaires, 54 - Vandoeuvre les Nancy (France)

    2002-09-01

    Plants provide new ways for soil remediation. The activity of living roots (absorption, exudation of organic compounds, action on physical soil properties) contribute to decrease the negative effects of pollutants, as they are stabilised or eliminated (extraction or degradation). In the presence of plants, hydrocarbons, a rather ubiquitous group of soil pollutants, are degraded faster than in bare soil. Hydrocarbon degrading bacteria are stimulated by root exudates, which also create favourable conditions for co-metabolism. Also, the fragmentation of aggregates as well as the release of surfactants increase the exposure of organic pollutants to microorganism degradation. The phyto-remediation technology is efficient to reduce the dissemination of pollutants. On historically contaminated soils, effects are generally discrete within a short period of time and may be more effective in the long run. (author)

  14. Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process

    DEFF Research Database (Denmark)

    Dias-Ferreira, Celia; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2015-01-01

    Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm−2), concentration of enhancing agent (0...... to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution....

  15. APPLICATION OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF A LEAD-CONTAMINATED SOIL

    Science.gov (United States)

    Earthworm acute toxicity, plant seed germination/root elongation (SG/RE) and plant genotoxicity bioassays were employed to evaluate the remediation of a lead-contaminated soil. The remediation involved removal of heavy metals by a soil washing/soil leaching treatment process. A p...

  16. Use of solar cell in electrokinetic remediation of cadmium-contaminated soil.

    Science.gov (United States)

    Yuan, Songhu; Zheng, Zhonghua; Chen, Jing; Lu, Xiaohua

    2009-03-15

    This preliminary study used a solar cell, instead of direct current (DC) power supply, to generate electric field for electrokinetic (EK) remediation of cadmium-contaminated soil. Three EK tests were conducted and compared; one was conducted on a cloudy and rainy day with solar cell, one was conducted on a sunny day with solar cell and another was conducted periodically with DC power supply. It was found that the output potential of solar cell depended on daytime and was influenced by weather conditions; the applied potential in soil was affected by the output potential and weather conditions, and the current achieved by solar cell was comparable with that achieved by DC power supply. Solar cell could be used to drive the electromigration of cadmium in contaminated soil, and removal efficiency achieved by solar cell was comparable with that achieved by DC power supply. Compared with traditional DC power supply, using solar cell as power supply for EK remediation can greatly reduce energy expenditure. This study provided an alternative to improve the EK soil remediation and expanded the use of solar cell in environmental remediation.

  17. Use of solar cell in electrokinetic remediation of cadmium-contaminated soil

    International Nuclear Information System (INIS)

    Yuan Songhu; Zheng Zhonghua; Chen Jing; Lu Xiaohua

    2009-01-01

    This preliminary study used a solar cell, instead of direct current (DC) power supply, to generate electric field for electrokinetic (EK) remediation of cadmium-contaminated soil. Three EK tests were conducted and compared; one was conducted on a cloudy and rainy day with solar cell, one was conducted on a sunny day with solar cell and another was conducted periodically with DC power supply. It was found that the output potential of solar cell depended on daytime and was influenced by weather conditions; the applied potential in soil was affected by the output potential and weather conditions, and the current achieved by solar cell was comparable with that achieved by DC power supply. Solar cell could be used to drive the electromigration of cadmium in contaminated soil, and removal efficiency achieved by solar cell was comparable with that achieved by DC power supply. Compared with traditional DC power supply, using solar cell as power supply for EK remediation can greatly reduce energy expenditure. This study provided an alternative to improve the EK soil remediation and expanded the use of solar cell in environmental remediation

  18. FEASIBILITY OF HYDRAULIC FRACTURING OF SOILS TO IMPROVE REMEDIAL ACTIONS

    Science.gov (United States)

    Hydraulic fracturing, a method of increasing fluid flow within the subsurface, should improve the effectiveness of several remedial techniques, including pump and treat, vapor extraction, bio-remediation, and soil-flushing. he technique is widely used to increase the yields of oi...

  19. Electrokinetic remediation of anionic contamination from unsaturated soil: Field application

    International Nuclear Information System (INIS)

    Lindgren, E.R.; Mattson, E.D.

    1995-01-01

    Electrokinetic remediation is an in situ technique under development at Sandia National Laboratories for removal of ionic contaminants from soil. While to date most other studies of this technique have focused on saturated soils, usually clays, the work at Sandia has been to extend the process to unsaturated sandy soils typical of arid regions. The impetus for this study is a chromate plume located beneath an old Sandia chemical waste landfill. Working in unsaturated soils is complicated by moisture control requirements, both to prevent undesired hydraulic transport of contamination outside the treatment zone and to optimize soil properties for efficient electrokinetic remediation. Two field tests will be discussed. First, a field test in clean soil is in progress to demonstrate moisture control with the Sandia electrode system. The second field demonstration, planned to begin the Fall of 1995, involves chromate removal from a in a chemical waste landfill

  20. Geotechnical behaviour of low-permeability soils in surfactant-enhanced electrokinetic remediation.

    Science.gov (United States)

    López-Vizcaíno, Rubén; Navarro, Vicente; Alonso, Juan; Yustres, Ángel; Cañizares, Pablo; Rodrigo, Manuel A; Sáez, Cristina

    2016-01-01

    Electrokinetic processes provide the basis of a range of very interesting techniques for the remediation of polluted soils. These techniques consist of the application of a current field in the soil that develops different transport mechanisms capable of mobilizing several types of pollutants. However, the use of these techniques could generate nondesirable effects related to the geomechanical behavior of the soil, reducing the effectiveness of the processes. In the case of the remediation of polluted soils with plasticity index higher than 35, an excessive shrinkage can be observed in remediation test. For this reason, the continued evaporation that takes place in the sample top can lead to the development of cracks, distorting the electrokinetic transport regime, and consequently, the development of the operation. On the other hand, when analyzing silty soils, in the surroundings of injection surfactant wells, high seepages can be generated that give rise to the development of piping processes. In this article methods are described to allow a reduction, or to even eliminate, both problems.

  1. A novel phytoremediation technology shown to remediate petroleum hydrocarbons from soils in situ

    Energy Technology Data Exchange (ETDEWEB)

    Huang, X.D.; Yu, X.M.; Gerhardt, K.; Glick, B.; Greenberg, B [Waterloo Environmental Biotechnology Inc., Hamilton, ON (Canada); Waterloo Univ., ON (Canada). Dept. of Biology

    2009-04-01

    This article described a newly developed, advanced microbe-enhanced phytoremediation system that can be used to remediate lands polluted by hydrocarbons, salts and metals. The technology uses 3 complementary processes to achieve effective remediation of strongly bound persistent organic pollutants (POPs) from soil. The remediation process involves physical soil treatment, photochemical photooxidation, microbial remediation and growth of plants treated with plant growth promoting rhizobacteria (PGPR). The PGPR-enhanced phytoremediation system (PEPS) alleviates plant stress and increases biodegradation activities, thereby accelerating plant growth in the presence of POPs or poor soils. The PEPS has been used successfully to remove petroleum hydrocarbons (PHCs) from impacted soils in situ at several sites across Canada. Studies have shown that the PHCs are degraded in the rhizosphere. This article also presented a summary of the work conducted at 3 sites in Alberta. It took only 2 years to remediate the 3 sites to levels required for site closure under Alberta Tier 1 guidelines. It was concluded that PEPS is equally effective for total PHC and Fraction 3 CCME hydrocarbons. 1 tab., 3 figs.

  2. Effect of electrokinetic remediation on indigenous microbial activity and community within diesel contaminated soil.

    Science.gov (United States)

    Kim, Seong-Hye; Han, Hyo-Yeol; Lee, You-Jin; Kim, Chul Woong; Yang, Ji-Won

    2010-07-15

    Electrokinetic remediation has been successfully used to remove organic contaminants and heavy metals within soil. The electrokinetic process changes basic soil properties, but little is known about the impact of this remediation technology on indigenous soil microbial activities. This study reports on the effects of electrokinetic remediation on indigenous microbial activity and community within diesel contaminated soil. The main removal mechanism of diesel was electroosmosis and most of the bacteria were transported by electroosmosis. After 25 days of electrokinetic remediation (0.63 mA cm(-2)), soil pH developed from pH 3.5 near the anode to pH 10.8 near the cathode. The soil pH change by electrokinetics reduced microbial cell number and microbial diversity. Especially the number of culturable bacteria decreased significantly and only Bacillus and strains in Bacillales were found as culturable bacteria. The use of EDTA as an electrolyte seemed to have detrimental effects on the soil microbial activity, particularly in the soil near the cathode. On the other hand, the soil dehydrogenase activity was enhanced close to the anode and the analysis of microbial community structure showed the increase of several microbial populations after electrokinetics. It is thought that the main causes of changes in microbial activities were soil pH and direct electric current. The results described here suggest that the application of electrokinetics can be a promising soil remediation technology if soil parameters, electric current, and electrolyte are suitably controlled based on the understanding of interaction between electrokinetics, contaminants, and indigenous microbial community. Copyright 2010 Elsevier B.V. All rights reserved.

  3. 1,4-Dioxane Remediation by Extreme Soil Vapor Extraction (XSVE). Screening-Level Feasibility Assessment and Design Tool in Support of 1,4-Dioxane Remediation by Extreme Soil Vapor Extraction (XSVE) ESTCP Project ER 201326

    Science.gov (United States)

    2017-10-01

    USER GUIDE 1,4-Dioxane Remediation by Extreme Soil Vapor Extraction (XSVE) Screening-Level Feasibility Assessment and Design Tool in...Support of 1,4-Dioxane Remediation by Extreme Soil Vapor Extraction (XSVE) ESTCP Project ER-201326 OCTOBER 2017 Rob Hinchee Integrated Science...Technology, Inc. 1509 Coastal Highway Panacea, FL 32346 8/8/2013 - 8/8/2018 10-2017 1,4-Dioxane Remediation by Extreme Soil Vapor Extraction (XSVE) Screening

  4. Remediation of uranium contaminated water and soil by PIMS approach

    International Nuclear Information System (INIS)

    Raicevic, S.; Raicevic, J.; Smiciklas, I. . E-mail address of corresponding author: raich@beotel.yu; Raicevic, S.)

    2005-01-01

    Contamination of soil by uranium (U) represents a permanent threat for food and water resources. For this reason, remediation is a very important measure for protection of the health of the population living in the vicinity of these contaminated sites. Phosphate- Induced Metal Stabilization (PIMS) represents one of the powerful methods for remediation of soil and water contaminated by U, including depleted uranium (DU). By this approach it is possible to stabilize metals in the form of phosphate phases and other low soluble phases that are stable over geological time. PIMS is based on application of a special form of apatite of biological origin, Apatite II, to clean up metal and radionuclide contamination, in situ or ex situ. This biogenic apatite can be emplaced as a down-gradient permeable reactive barrier, mixed into contaminated soil or waste or used as a disposal liner. Here we will briefly describe the PIMS remediation protocol. (author)

  5. Remediation mechanisms of mercapto-grafted palygorskite for cadmium pollutant in paddy soil.

    Science.gov (United States)

    Liang, Xuefeng; Qin, Xu; Huang, Qingqing; Huang, Rong; Yin, Xiuling; Cai, Yanming; Wang, Lin; Sun, Yuebing; Xu, Yingming

    2017-10-01

    The immobilization agent was the key factor that determined the success of remediation of heavy metal polluted soil. In this study, mercapto-grafted palygorskite (MP) as a novel and efficient immobilization agent was utilized for the remediation of Cd-polluted paddy soil in pot trials, and the remediation mechanisms were investigated in the aspect of soil chemistry and plant physiology with different rice cultivars as model plants. Mercapto-grafted palygorskite at applied doses of 0.1-0.3% could reduce Cd contents of brown rice and straws of different cultivars significantly. Both reduced DTPA-extractable Cd contents in rhizosphere and non-rhizosphere soil and decreasing Cd contents in iron plaques on rice root surfaces confirmed that MP was an efficient immobilization agent for Cd pollutant in paddy soil. In the aspect of soil chemistry, the pH values of rhizosphere and non-rhizosphere soils had no statistical changes in the MP treatment groups, but their zeta potentials decreased obviously, indicating that MP could enhance the fixation or sorption of Cd on soil compositions. In the aspect of antioxidant system, MP could increase POD activity of rice roots significantly to alleviate the stress of Cd to roots, and resulted in the decrease of T-AOC, SOD, and CAT activities of rice roots of the selected cultivars. MP had no inhabitation or enhancement effects on TSH of rice roots but enhance the contents of MTs and NPT to binding Cd to complete detoxification process. MP as a novel and efficient immobilization agent could complete the remediation effects through soil chemistry and plant physiological mechanisms.

  6. Setting a benchmark in remediation

    International Nuclear Information System (INIS)

    Ong, Jacqueline

    2014-01-01

    Full text: Thiess Services has achieved a first in the treatment of contaminated soil, in the process assisting Orica in successfully removing a toxic legacy. In 1980, when Orica Australia's predecessor ICI Australia constructed its car park waste encapsulation (CPWE) to seal off contaminated soil at Botany Industrial Park, 12km south of the Sydney CBD, treatment methods were not available. Fast-forward more than 30 years and Thiess Services has successfully undertaken treatment of the soil, earning it the 2013 CARE award. The contaminated soil contained hexachlorobutadiene (HCBD), low levels of hexachlorobenzene and hexachloroethane, all by-products of historical manufacturing of chlorinated solvents, including dry cleaning fluid, in the 1960s and 1970s. ICI Australia decided initially to store the contaminated material in drums and place it on a bed of boiler ash. However, drum corrosion led to contamination of the ash bed and underlying soil, so the company decided to encapsulate the material within a synthetic Hypalon liner, covering it with clean soil and capping it with bitumen in a 45,000 cubic metre cell. In 2005, Orica commissioned Thiess to assess a range of remediation methods and technologies to treat the material. Three options were recommended — directly heated thermal desorption, in situ thermal desorption and indirectly heated thermal desorption. “Together with Orica, we decided that directly heated thermal desorption was the appropriate technology to use,” Thiess project manager Joshua Van Der Heiden said. “Essentially, the soil is introduced into a rotary kiln and a flame directly heats up the soil above the contaminants' boiling point (up to a maximum of 450C) so that the contaminants are volatilised and the soil comes out clean. The gas separated from the soil is then heated to around 1000C in a thermal oxidiser, converting it into carbon dioxide and water. To prevent contaminants from reforming, the gas stream is rapidly cooled by a

  7. GROUND WATER ISSUE: STEAM INJECTION FOR SOIL AND AQUIFER REMEDIATION

    Science.gov (United States)

    The purpose of this Issue Paper is to provide to those involved in assessing remediation technologies for specific sites basic technical information on the use of steam injection for the remediation of soils and aquifers that are contaminated by volatile or semivolatile organic c...

  8. Case studies illustrating in-situ remediation methods for soil and groundwater contaminated with petrochemicals

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, Robert A; Lance, P E; Downs, A; Kier, Brian P [EMCON Northwest Inc., Portland, OR (United States)

    1994-12-31

    Four case studies of successful in-situ remediation are summarized illustrating cost-effective methods to remediate soil and groundwater contaminated with volatile and non-volatile petrochemicals. Each site is in a different geologic environment with varying soil types and with and without groundwater impact. The methods described include vadose zone vapor extraction, high-vacuum vapor extraction combined with groundwater tab.le depression, air sparging with groundwater recovery and vapor extraction, and bio remediation of saturated zone soils using inorganic nutrient and oxygen addition

  9. Case studies illustrating in-situ remediation methods for soil and groundwater contaminated with petrochemicals

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, Robert A.; Lance, P.E.; Downs, A.; Kier, Brian P. [EMCON Northwest Inc., Portland, OR (United States)

    1993-12-31

    Four case studies of successful in-situ remediation are summarized illustrating cost-effective methods to remediate soil and groundwater contaminated with volatile and non-volatile petrochemicals. Each site is in a different geologic environment with varying soil types and with and without groundwater impact. The methods described include vadose zone vapor extraction, high-vacuum vapor extraction combined with groundwater tab.le depression, air sparging with groundwater recovery and vapor extraction, and bio remediation of saturated zone soils using inorganic nutrient and oxygen addition

  10. Co-remediation of the lead-polluted garden soil by exogenous natural zeolite and humic acids.

    Science.gov (United States)

    Shi, Wei-yu; Shao, Hong-bo; Li, Hua; Shao, Ming-an; Du, Sheng

    2009-08-15

    The current study reported the co-remediation effect on the lead-polluted garden soil by zeolite and humic acids (HA), which was from comparing with the remediation of single zeolite in term of the lead fraction of sequential extraction in the soil and the distribution of lead in different parts of rape. Mixed treatment (zeolite and HA) and single treatment (zeolite) were, respectively, applied to the artificially polluted garden soil to examine the difference of their remediation effects in pot experiment. Results indicated that the co-remediation led to significantly greater (plead concentration in plants than by singly adding to zeolite. The co-application of zeolite and HA reduced the available fraction of lead compounds, but slightly increased (plead compounds in the garden soil, compared with the application of single zeolite, especially in the severe lead-polluted soil (> or =1000 mg kg(-1)). This method might be an efficient way to remediate the lead-polluted soils on a large scale, although zeolite is a kind of hazardous material.

  11. Remediation of Steel Slag on Acidic Soil Contaminated by Heavy Metal

    OpenAIRE

    Gu, Haihong; Li, Fuping; Guan, Xiang; Li, Zhongwei; Yu, Qiang

    2013-01-01

    The technology of in situ immobilization with amendments is an important measure that remediates the soil contaminated by heavy metal, and selecting economical and effective modifier is the key. The effects and mechanism of steel slag, the silicon-rich alkaline by-product which can remediate acidic soil contaminated by heavy metal, are mainly introduced in this paper to provide theory inferences for future research. Firstly, the paper analyzes current research situation of in situ immobilizat...

  12. Modern approaches to remediation of heavy metal polluted soils: A review

    Science.gov (United States)

    Koptsik, G. N.

    2014-07-01

    The main principles and approaches to remediation of in situ polluted soils aimed at the removal or control of heavy metals (washing, stabilization, phytoremediation, and natural restoration) are analyzed. The prospects of gentle methods of stabilization oriented at the reduction of the mobility and biological availability of heavy metals due to the processes of adsorption, ionic exchange, and precipitation are emphasized. The use of sorbents and the traditional application of liming and phosphates to fix metal pollutants in soils is considered. The necessary conditions for successful soil remediation are the assessment of its economic efficiency, the analysis of the ecological risks, and confirming the achievement of the planned purposes related to the content of available metals in the soils.

  13. Effects from different types of construction refuse in the soil on electrodialytic remediation

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Eriksson, Thomas; Hansen, Henrik K.

    2002-01-01

    At abandoned industrial sites some of the previous buildings are often left behind. If the soil at such site is polluted with heavy metals and is to be remediated by an electrochemical method, the construction refuse within the soil matrix will influence the remediation action. The influence of d...

  14. Tannic acid for remediation of historically arsenic-contaminated soils.

    Science.gov (United States)

    Gusiatin, Zygmunt Mariusz; Klik, Barbara; Kulikowska, Dorota

    2017-12-22

    Soil washing effectively and permanently decreases soil pollution. Thus, it can be considered for the removal of the most toxic elements, for example arsenic (As). In this study, historically As-contaminated soils (2041-4294 mg/kg) were remediated with tannic acid (TA) as the washing agent. The scope of this study included optimization of the operational conditions of As removal, determination of As distribution in soil before and after double soil washing, and measurement of TA loss during washing. The optimum conditions for As removal were 4% TA, pH 4 and 24 h washing time. The average As removal after single and double washings was 38% and 63%, respectively. TA decreased As content in amorphous and poorly crystalline oxides by >90%. Although TA increased the amount of As in the easily mobilizable As fraction, the stability of As in washed soils increased, with reduced partition indexes of 0.52-0.66 after washing. The maximum capacity of the soils to adsorb TA (q max ) was 50.2-70.4 g C/kg. TA sorption was higher at alkaline than at acidic conditions. Only TA removes As from soils effectively if the proportion of As in amorphous and poorly crystalline oxides is high. Thus, it can be considered for remediation of historically contaminated soils.

  15. Electrodialytic remediation of polychlorinated biphenyls contaminated soil with iron nanoparticles and two different surfactants

    DEFF Research Database (Denmark)

    Gomes, Helena I.; Dias-Ferreira, Celia; Ottosen, Lisbeth M.

    2014-01-01

    Polychlorinated biphenyls (PCB) are persistent organic pollutants (POP) that strongly adsorb in soils and sediments. There is a need to develop new and cost-effective solutions for the remediation of PCB contaminated soils. The suspended electrodialytic remediation combined with zero valent iron......ZVI showed encouraging tendencies and a base is thus formed for further optimization towards a new method for remediation of PCB polluted soils....... nanoparticles (nZVI) could be a competitive alternative to the commonly adapted solutions of incineration or landfilling. Surfactants can enhance the PCB desorption, dechlorination, and the contaminated soil cleanup. In this work, two different surfactants (saponin and Tween 80) were tested to enhance PCB...

  16. Microorganisms in heavy metal bioremediation: strategies for applying microbial-community engineering to remediate soils

    Directory of Open Access Journals (Sweden)

    Jennifer L. Wood

    2016-06-01

    Full Text Available The remediation of heavy-metal-contaminated soils is essential as heavy metals persist and do not degrade in the environment. Remediating heavy-metal-contaminated soils requires metals to be mobilized for extraction whilst, at the same time, employing strategies to avoid mobilized metals leaching into ground-water or aquatic systems. Phytoextraction is a bioremediation strategy that extracts heavy metals from soils by sequestration in plant tissues and is currently the predominant bioremediation strategy investigated for remediating heavy-metal-contaminated soils. Although the efficiency of phytoextraction remains a limiting feature of the technology, there are numerous reports that soil microorganisms can improve rates of heavy metal extraction.This review highlights the unique challenges faced when remediating heavy-metal-contaminated soils as compared to static aquatic systems and suggests new strategies for using microorganisms to improve phytoextraction. We compare how microorganisms are used in soil bioremediation (i.e. phytoextraction and water bioremediation processes, discussing how the engineering of microbial communities, used in water remediation, could be applied to phytoextraction. We briefly outline possible approaches for the engineering of soil communities to improve phytoextraction either by mobilizing metals in the rhizosphere of the plant or by promoting plant growth to increase the root-surface area available for uptake of heavy metals. We highlight the technological advances that make this research direction possible and how these technologies could be employed in future research.

  17. Soil and groundwater remediation using dual-phase extraction technology

    International Nuclear Information System (INIS)

    Miller, A.W.; Gan, D.R.

    1995-01-01

    A gasoline underground storage tank (UST) was formerly used to fuel vehicles for a hospital in Madison, Wisconsin. Elevated concentrations of gasoline range organics (GRO) were observed in soils and groundwater at the site during the tank removal and a subsequent site investigation. Based on the extent of soil and groundwater contamination, a dual-phase extraction technology was selected as the most cost effective alternative to remediate the site. The dual-phase extraction system includes one extraction well functioning both as a soil vapor extraction (SVE) and groundwater recovery well. After six months of operation, samples collected from the groundwater monitoring wells indicated that the groundwater has been cleaned up to levels below the Wisconsin preventative action limits. The dual-phase extraction system effectively remediated the site in a short period of time, saving both operation and maintenance costs and overall project cost

  18. Remediation of lead-contaminated soils

    International Nuclear Information System (INIS)

    Peters, R.W.; Shem, L.

    1992-01-01

    Excavation and transport of soil contaminated with heavy metals has generally been the standard remediation technique for treatment of heavy-metal-contaminated soils. This approach is not a permanent solution; moreover, off-site shipment and disposal of contaminated soil involves high expense, liability, and appropriate regulatory approval. Recently, a number of other techniques have been investigated for treating such contaminated sites, including flotation, solidification/stabilization, vitrification, and chemical extraction. This paper reports the results of a laboratory investigation determining the efficiency of using chelating agents to extract lead from contaminated soils. Lead concentrations in the soils ranged from 500 to 10,000 mg/kg. Ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) were examined for their potential extractive capabilities. Concentrations of the chelating agents ranged from 0.01 to 0.10 M. The pH of the suspensions in which the extractions were performed ranged from 4 to 12. Results showed that the removal of lead using NTA and water was ph-dependent, whereas the removal of lead using EDTA was ph-insensitive. Maximum removals of lead were 68.7%,19.1%, and 7.3% using EDTA, NTA, and water, respectively (as compared with initial lead concentrations)

  19. A comparison of technologies for remediation of heavy metal contaminated soils

    OpenAIRE

    Khalid , Sana; Shahid , Muhammad; Niazi , Nabeel Khan; Murtaza , Behzad; Bibi , Irshad; Dumat , Camille

    2016-01-01

    International audience; Soil contamination with persistent and potentially (eco)toxic heavy metal(loid)s is ubiquitous around the globe. Concentration of these heavy metal(loid)s in soil has increased drastically over the last three decades, thus posing risk to the environment and human health. Some technologies have long been in use to remediate the hazardous heavy metal(loid)s. Conventional remediation methods for heavy metal(loid)s are generally based on physical, chemical and biological a...

  20. Electrochemical remediation technologies for soil and groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Doering, F. [Electrochemical Processes I.I. c. Valley Forge, PA (United States)]|[P2 Soil Remediation, Inc. Stuttgart (Germany); Doering, N. [P2 Soil Remediation, Inc. Stuttgart (Germany)

    2001-07-01

    In Direct Current Technologies (DCTs) a direct current electricity is passed between at least two subsurface electrodes in order to effect the remediation of the groundwater and/or the soil. DCTs in line with the U.S.-terminology comprise of the ElectroChemical Remediation Technologies (ECRTs), and GeoKinetics. The primary distinction between ECRTs and ElectroKinetics are the power input, and the mode of operation, which are electrochemical reactions vs. mass transport. ECRTs combine phenomena of colloid (surface) electrochemistry with the phenomena of Induced Polarization (IP). This report focuses on ECRTs, comprising of the ElectroChemical GeoOxidation (ECGO) for the mineralization of organic pollutants to finally carbon dioxide and water, and Induced Complexation (IC), related to the electrochemical conversion of metals enhancing the mobilization and precipitation of heavy metals on both electrodes. Both technologies are based on reduction-oxidation (redox) reactions at the scale of the individual soil particles. (orig.)

  1. Dynamics And Remediation Of Fine Textured Soils And Ground Water Contaminated With Salts And Chlorinated Organic Compounds

    Science.gov (United States)

    Murata, Alison; Naeth, M. Anne

    2017-04-01

    Soil and ground water are frequently contaminated by industrial activities, posing a potential risk to human and environmental health and limiting land use. Proper site management and remediation treatments can return contaminated areas to safe and useful states. Most remediation research focuses on single contaminants in coarse and medium textured soils. Contaminant mixtures are common and make remediation efforts complex due to differing chemical properties. Remediation in fine textured soils is difficult since their low hydraulic conductivities hinder addition of amendments into and removal of contaminated media out of the impacted zone. The objective of this research is to assess contaminant dynamics and potential remediation techniques for fine textured soil and ground water impacted by multiple contaminants in Edmonton, Alberta, Canada. The University of Alberta's Ellerslie Waste Management Facility was used to process liquid laboratory waste from 1972 to 2007. A waste water pond leak prior to 1984 resulted in salt and chlorinated organic compound contamination. An extensive annual ground water monitoring data set for the site is available since 1988. Analytical parameters include pH, electrical conductivity, major ions, volatile organic compounds, and metals. Data have been compared to Alberta Tier 1 Soil and Groundwater Remediation Guidelines to identify exceedances. The parameters of greatest concern, based on magnitude and frequency of detection, are electrical conductivity, sodium, chloride, chloroform, and dichloromethane. Spatial analyses of the data show that the contamination is focused in and down gradient of the former waste water pond. Temporal analyses show different trends depending on monitoring well location. Laboratory column experiments were used to assess leaching as a potential treatment for salt contamination in fine textured soils. Saturated hydraulic conductivity was measured for seven soils from two depth intervals with or without

  2. Study of the mechanism of remediation of Cd-contaminated soil by novel biochars.

    Science.gov (United States)

    Tan, Zhongxin; Wang, Yuanhang; Zhang, Limei; Huang, Qiaoyun

    2017-11-01

    This article used novel non-magnetized and magnetized biochars prepared under a CO 2 atmosphere returned to Cd-contaminated soil and compared these to the effects of conventional biochars prepared under a N 2 atmosphere with regard to Cd-contaminated soil remediation. A pot experiment with lettuce (Lactuca sativa) was conducted to investigate the relative soil remediation effects of these biochars. The soil used for the pot experiment was spiked with 20 mg kg -1 Cd and amended with 5% of a biochar before sowing. Through these research works, some important results were obtained as follows: (1) applying biochar treated by pyrolysis under a CO 2 atmosphere can obtain the best remediation effect of Cd-contaminated soil that the content of cadmium in the lettuce roots, stems, and leaves was reduced 67, 62, and 63%, respectively; (2) the magnetic biochar aggregation for the soil is weak, so the heavy metal cadmium in the soil could not be immobilized well by the magnetic biochar; (3) The remediation mechanism of novel biochars is that biochar includes a large number of organic functional groups (-C-OH, -C=O, COO-) that can act in a complexing reaction with heavy metal Cd(II) and the inorganic salt ions (Si, S, Cl, etc.) that can combine with cadmium and generate a stable combination.

  3. Enhanced electrokinetic remediation of lead-contaminated soil by complexing agents and approaching anodes.

    Science.gov (United States)

    Zhang, Tao; Zou, Hua; Ji, Minhui; Li, Xiaolin; Li, Liqiao; Tang, Tang

    2014-02-01

    Optimizing process parameters that affect the remediation time and power consumption can improve the treatment efficiency of the electrokinetic remediation as well as determine the cost of a remediation action. Lab-scale electrokinetic remediation of Pb-contaminated soils was investigated for the effect of complexant ethylenediaminetetraacetic acid (EDTA) and acetic acid and approaching anode on the removal efficiency of Pb. When EDTA was added to the catholyte, EDTA dissolved insoluble Pb in soils to form soluble Pb-EDTA complexes, increasing Pb mobility and accordingly removal efficiency. The removal efficiency was enhanced from 47.8 to 61.5 % when the EDTA concentration was increased from 0.1 to 0.2 M, showing that EDTA played an important role in remediation. And the migration rate of Pb was increased to 72.3 % when both EDTA and acetic acid were used in the catholyte. The "approaching anode electrokinetic remediation" process in the presence of both EDTA and acetic acid had a higher Pb-removal efficiency with an average efficiency of 83.8 %. The efficiency of electrokinetic remediation was closely related to Pb speciation. Exchangeable and carbonate-bounded Pb were likely the forms which could be removed. All results indicate that the approaching anode method in the presence of EDTA and acetic acid is an advisable choice for electrokinetic remediation of Pb-contaminated soil.

  4. Electrodialytic soil remediation in a small pilot plant (Part II)

    DEFF Research Database (Denmark)

    Karlsmose, Bodil; Hansen, Lene

    1999-01-01

    -monia. Ammonia was chosen because it forms strong complexes with copper and to keep the soil basic, so that the carbonates were not dissolved. The bulk soil was treated by electrodialytic reme-dia-tion, and soil treated for seven months was investigated with XRD, TEM and SEM.Malachite was found by use of XRD...

  5. Phyto-remediation of contaminated soils

    International Nuclear Information System (INIS)

    Chagvardieff, P.

    2014-01-01

    Some plants can be selected for their capacity to extract radionuclides from the soil, on the contrary other plants can be chosen for being able to produce food grade products in a contaminated environment. Modern genetic methods can be used to enhance these abilities and turn some plants into an efficient means in the managing of contaminated areas. The DEMETERRES project that gathers different research organisations like CEA, IRSN and INRA and industrial partners like AREVA and VEOLIA aims at developing innovative bio-technologies like phyto-extraction and environment friendly physico-chemical technologies for the remediation of contaminated soils. This project was launched in 2013 on a 5-year scheme and is expected to lead to industrial applications. (A.C.)

  6. Efficiency of modified chemical remediation techniques for soil contaminated by organochlorine pesticides

    Science.gov (United States)

    Correa-Torres, S. N.; Kopytko, M.; Avila, S.

    2016-07-01

    This study reports the optimization of innovation chemical techniques in order to improve the remediation of soils contaminated with organochloride pesticides. The techniques used for remediation were dehalogenation and chemical oxidation in soil contaminated by pesticides. These techniques were applied sequentially and combined to evaluate the design optimize the concentration and contact time variables. The soil of this study was collect in cotton crop zone in Agustin Codazzi municipality, Colombia, and its physical properties was measure. The modified dehalogenation technique of EPA was applied on the contaminated soil by adding Sodium Bicarbonate solution at different concentrations and rates during 4, 7 and 14 days, subsequently oxidation technique was implemented by applying a solution of KMnO4 at different concentration and reaction times. Organochlorine were detected by Gas Chromatography analysis coupled Mass Spectrometry and its removals were between 85.4- 90.0% of compounds such as 4, 4’-DDT, 4,4’-DDD, 4,4-DDE, trans-Clordane y Endrin. These results demonstrate that the technique of dehalogenation with oxidation chemistry can be used for remediation soils contaminated by organochloride pesticides.

  7. Soil remediation: humic acids as natural surfactants in the washings of highly contaminated soils

    International Nuclear Information System (INIS)

    Conte, Pellegrino; Agretto, Anna; Spaccini, Riccardo; Piccolo, Alessandro

    2005-01-01

    The remediation of the highly contaminated site around the former chemical plant of ACNA (near Savona) in Northern Italy is a top priority in Italy. The aim of the present work was to contribute in finding innovative and environmental-friendly technology to remediate soils from the ACNA contaminated site. Two soils sampled from the ACNA site (A and B), differing in texture and amount and type of organic contaminants, were subjected to soil washings by comparing the removal efficiency of water, two synthetic surfactants, sodium dodecylsulphate (SDS) and Triton X-100 (TX100), and a solution of a natural surfactant, a humic acid (HA) at its critical micelle concentration (CMC). The extraction of pollutants by sonication and soxhlet was conducted before and after the soil washings. Soil A was richer in polycyclic aromatic hydrocarbons, whereas soil B had a larger content of thiophenes. Sonication resulted more analytically efficient in the fine-textured soil B. The coarse-textured soil A was extracted with a general equal efficiency also by soxhlet. Clean-up by water was unable to exhaustively remove contaminants from the two soils, whereas all the organic surfactants revealed very similar efficiencies (up to 90%) in the removal of the contaminants from the soils. Hence, the use of solutions of natural HAs appears as a better choice for soil washings of highly polluted soils due to their additional capacity to promote microbial activity, in contrast to synthetic surfactants, for a further natural attenuation in washed soils. - Solutions of natural humic acids appear to be a better choice for washing highly polluted soils

  8. Remediation of heavy metal contaminated soils by using Solanum nigrum: A review.

    Science.gov (United States)

    Rehman, Muhammad Zia Ur; Rizwan, Muhammad; Ali, Shafaqat; Ok, Yong Sik; Ishaque, Wajid; Saifullah; Nawaz, Muhammad Farrakh; Akmal, Fatima; Waqar, Maqsooda

    2017-09-01

    Heavy metals are among the major environmental pollutants and the accumulation of these metals in soils is of great concern in agricultural production due to the toxic effects on crop growth and food quality. Phytoremediation is a promising technique which is being considered as an alternative and low-cost technology for the remediation of metal-contaminated soils. Solanum nigrum is widely studied for the remediation of heavy metal-contaminated soils owing to its ability for metal uptake and tolerance. S. nigrum can tolerate excess amount of certain metals through different mechanism including enhancing the activities of antioxidant enzymes and metal deposition in non-active parts of the plant. An overview of heavy metal uptake and tolerance in S. nigrum is given. Both endophytic and soil microorganisms can play a role in enhancing metal tolerance in S. nigrum. Additionally, optimization of soil management practices and exogenous application of amendments can also be used to enhance metal uptake and tolerance in this plant. The main objective of the present review is to highlight and discuss the recent progresses in using S. nigrum for remediation of metal contaminated soils. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. A critical assessment of asphalt batching as a viable remedial option for hydrocarbon contaminated soils

    International Nuclear Information System (INIS)

    Elliott, E.J.; Brashears, D.F.

    1991-01-01

    Hot mix asphalt production equipment has been successfully utilized in the remediation of soils contaminated with petroleum hydrocarbons. This paper reports that there are two major ways in which this equipment can be used to remediate the petroleum contaminated soils; by incorporating the contaminated soil in the hot mix asphalt product or by using the equipment to clean the soil thermally of the contaminant, leaving a clean soil material. Both of these processes have limitations encompassing technical, political, and certainly liability problems. The remediation of contaminated soil in hot mix asphalt facilities is primarily a physical phenomenon relying on laws of heat and mass transfer. Although chemical changes do occur, the primary function of the process is to cause a physical separation of the contaminant from the soils

  10. Evaluation of the effectiveness of sepiolite, bentonite, and phosphate amendments on the stabilization remediation of cadmium-contaminated soils.

    Science.gov (United States)

    Sun, Yuebing; Sun, Guohong; Xu, Yingming; Liu, Weitao; Liang, Xuefeng; Wang, Lin

    2016-01-15

    A pot trial was conducted to assess the effectiveness of sepiolite, bentonite, and phosphate on the immobilization remediation of cadmium (Cd)-contaminated soils using a set of variables, namely, physiological traits, sequential extraction procedure, plant growth and Cd concentration, and soil enzymatic activities and microbial population. Results showed that superoxide dismutase and peroxidase activities in the leaves of Oryza sativa L. and catalase activities in soils were stimulated after applying the amendments. However, soluble protein contents in leaves and urease and invertase activities in soils were reduced from 7.1% to 31.7%, 1.0%-23.3%, and 21.1%-62.5%, respectively, compared with the control. Results of the sequence extraction procedures revealed that the exchangeable fraction of Cd in soils was mostly converted into carbonated-associated forms. The water soluble plus exchangeable fraction (SE) of Cd in soil decreased when treated with single and compound materials of sepiolite, bentonite and phosphate, which resulted in 13.2%-69.2% reduction compared with that of CK (control test). The amendments led to decreased Cd concentrations in roots, stems, leaves, brown rice, and rice hull by 16.2%-54.5%, 16.6%-42.8%, 19.6%-59.6%, 5.0%-68.2%, and 6.2%-20.4%, respectively. Higher bacterial and actinomycete amount indicated that remediation measures improved soil environmental quality. Composite amendments could be more efficiently used for the stabilization remediation of Cd contaminated soils with low Cd uptake and translocation in the plants and available contents of Cd in soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. In Situ Evaluation of Crop Productivity and Bioaccumulation of Heavy Metals in Paddy Soils after Remediation of Metal-Contaminated Soils.

    Science.gov (United States)

    Kim, Shin Woong; Chae, Yooeun; Moon, Jongmin; Kim, Dokyung; Cui, Rongxue; An, Gyeonghyeon; Jeong, Seung-Woo; An, Youn-Joo

    2017-02-15

    Soils contaminated with heavy metals have been reused for agricultural, building, and industrial uses following remediation. This study assesses plant growth and bioaccumulation of heavy metals following remediation of industrially contaminated soil. The soil was collected from a field site near a nonferrous smelter and was subjected to laboratory- and field-scale studies. Soil from the contaminated site was remediated by washing with acid or mixed with soil taken from a distant uncontaminated site. The activities of various soil exoenzymes, the rate of plant growth, and the bioaccumulations of six heavy metals were measured to assess the efficacy of these bioremediation techniques. Growth of rice (Oryza sativa) was unaffected in acid-washed soil or the amended soil compared to untreated soil from the contaminated site. The levels of heavy metals in the rice kernels remained within safe limits in treated and untreated soils. Rice, sorghum (Sorghum bicolor), and wheat (Triticum aestivum) cultivated in the same soils in the laboratory showed similar growth rates. Soil exoenzyme activities and crop productivity were not affected by soil treatment in field experiments. In conclusion, treatment of industrially contaminated soil by acid washing or amendment did not adversely affect plant productivity or lead to increased bioaccumulation of heavy metals in rice.

  12. Microwave thermal remediation of crude oil contaminated soil enhanced by carbon fiber.

    Science.gov (United States)

    Li, Dawei; Zhang, Yaobin; Quan, Xie; Zhao, Yazhi

    2009-01-01

    Thermal remediation of the soil contaminated with crude oil using microwave heating enhanced by carbon fiber (CF) was explored. The contaminated soil was treated with 2.45 GHz microwave, and CF was added to improve the conversion of microwave energy into thermal energy to heat the soil. During microwave heating, the oil contaminant was removed from the soil matrix and recovered by a condensation system of ice-salt bath. The experimental results indicated that CF could efficiently enhance the microwave heating of soil even with relatively low-dose. With 0.1 wt.% CF, the soil could be heated to approximately 700 degrees C within 4 min using 800 W of microwave irradiation. Correspondingly, the contaminated soil could be highly cleaned up in a short time. Investigation of oil recovery showed that, during the remediation process, oil contaminant in the soil could be efficiently recovered without causing significant secondary pollution.

  13. SITE Technology Capsule. Demonstration of Rocky Mountain Remediation Services Soil Amendment

    Science.gov (United States)

    This report briefly summarizes the Rocky Mountain Remediation Services treatment technology demonstration of a soil amendment process for lead contaminated soil at Roseville, OH. The evaluation included leaching, bioavailability, geotechnical, and geochemical methods.

  14. SF Box--a tool for evaluating the effects on soil functions in remediation projects.

    Science.gov (United States)

    Volchko, Yevheniya; Norrman, Jenny; Rosén, Lars; Norberg, Tommy

    2014-10-01

    Although remediation is usually aimed at reducing the risks posed by contaminants to human health and the environment, it is also desirable that the remediated soil within future green spaces is capable of providing relevant ecological functions, e.g., basis for primary production. Yet while addressing a contamination problem by reducing contaminant concentration and/or amounts in the soil, the remedial action itself can lead to soil structure disturbances, decline in organic matter and nutrient deficiencies, and in turn affect a soil's capacity to carry out its ecological soil functions. This article presents the Soil Function Box (SF Box) tool that is aimed to facilitate integration of information from suggested soil quality indicators (SQIs) into a management process in remediation using a scoring method. The scored SQIs are integrated into a soil quality index corresponding to 1 of 5 classes. SF Box is applied to 2 cases from Sweden (Kvillebäcken and Hexion), explicitly taking into consideration uncertainties in the results by means of Monte Carlo simulations. At both sites the generated soil quality indices corresponded to a medium soil performance (soil class 3) with a high certainty. The main soil constraints at both Kvillebäcken and Hexion were associated with biological activity in the soil, as soil organisms were unable to supply plant-available N. At the Kvillebäcken site the top layer had a content of coarse fragment (ø > 2 mm) higher than 35%, indicating plant rooting limitations. At the Hexion site, the soil had limited amount of organic matter, thus poor aggregate stability and nutrient cycling potential. In contrast, the soil at Kvillebäcken was rich in organic matter. The soils at both sites were capable of storing a sufficient amount of water for soil organisms between precipitation events. © 2014 SETAC.

  15. Effect of soil organic matter on antimony bioavailability after the remediation process

    International Nuclear Information System (INIS)

    Nakamaru, Yasuo Mitsui; Martín Peinado, Francisco José

    2017-01-01

    We evaluated the long-term (18 year) and short-term (4 weeks) changes of Sb in contaminated soil with SOM increase under remediation process. In the Aznalcóllar mine accident (1998) contaminated area, the remediation measurement implemented the Guadiamar Green Corridor, where residual pollution is still detected. Soils of the re-vegetated area (O2) with high pH and high SOM content, moderately re-vegetated area (O1) and unvegetated area (C) were sampled. Soil pH, CEC, SOM amount and soil Sb forms were evaluated. Soil Sb was measured as total, soluble, exchangeable, EDTA extractable, acid oxalate extractable, and pyro-phosphate extractable fractions. Further, the short-term effect of artificial organic matter addition was also evaluated with incubation study by adding compost to the sampled soil from C, O1 and O2 areas. After 4 weeks of incubation, soil chemical properties and Sb forms were evaluated. In re-vegetated area (O2), soil total Sb was two times lower than in unvegetated area (C); however, soluble, exchangeable, and EDTA extractable Sb were 2–8 times higher. The mobile/bioavailable Sb increase was also observed after 4 weeks of incubation with the addition of compost. Soluble, exchangeable, and EDTA extractable Sb was increased 2–4 times by compost addition. By the linear regression analysis, the significantly related factors for soluble, exchangeable, and EDTA extractable Sb values were pH, CEC, and SOM, respectively. Soluble Sb increase was mainly related to pH rise. Exchangeable Sb should be bound by SOM-metal complex and increased with CEC. EDTA extractable fraction should be increased with increase of SOM as SOM-Fe associated Sb complex. From these results, it was shown that increase of SOM under natural conditions or application of organic amendment under remediation process should increase availability of Sb to plants. - Highlights: • The effect of SOM on Sb availability was evaluated after the remediation process. • Increase in SOM raised

  16. An experimental study on the bio-surfactant-assisted remediation of crude oil and salt contaminated soils.

    Science.gov (United States)

    Zhang, Wen; Li, Jianbing; Huang, Guohe; Song, Weikun; Huang, Yuefei

    2011-01-01

    The effect of bio-surfactant (rhamnolipid) on the remediation of crude oil and salt contaminated soil was investigated in this study. The experimental results indicated that there was a distinct decline of total petroleum hydrocarbon (TPH) concentration within the soil when using rhamnolipid during a remediation period of 30 days, with maximum TPH reduction of 86.97%. The most effective remediation that was observed was with rhamnolipid at a concentration of 2 CMC in soil solution, and a first-order TPH degradation rate constant of 0.0866 d(-1). The results also illustrated that salts in soil had a negative impact on TPH reduction, and the degradation rate was negatively correlated with NaCl concentration in soil solution. The analysis of soil TPH fractions indicated that there was a significant reduction of C13-C30 during the remediation process when using bio-surfactant.

  17. Remediation of soils contaminated with heavy metals with an emphasis on immobilization technology.

    Science.gov (United States)

    Derakhshan Nejad, Zahra; Jung, Myung Chae; Kim, Ki-Hyun

    2018-06-01

    The major frequent contaminants in soil are heavy metals which may be responsible for detrimental health effects. The remediation of heavy metals in contaminated soils is considered as one of the most complicated tasks. Among different technologies, in situ immobilization of metals has received a great deal of attention and turned out to be a promising solution for soil remediation. In this review, remediation methods for removal of heavy metals in soil are explored with an emphasis on the in situ immobilization technique of metal(loid)s. Besides, the immobilization technique in contaminated soils is evaluated through the manipulation of the bioavailability of heavy metals using a range of soil amendment conditions. This technique is expected to efficiently alleviate the risk of groundwater contamination, plant uptake, and exposure to other living organisms. The efficacy of several amendments (e.g., red mud, biochar, phosphate rock) has been examined to emphasize the need for the simultaneous measurement of leaching and the phytoavailability of heavy metals. In addition, some amendments that are used in this technique are inexpensive and readily available in large quantities because they have been derived from bio-products or industrial by-products (e.g., biochar, red mud, and steel slag). Among different amendments, iron-rich compounds and biochars show high efficiency to remediate multi-metal contaminated soils. Thereupon, immobilization technique can be considered a preferable option as it is inexpensive and easily applicable to large quantities of contaminants derived from various sources.

  18. Remediation of flare pit soils using supercritical fluid extraction

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, V.; Guigard, S.E. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil Engineering

    2005-09-01

    A laboratory study was conducted to examine the ability of supercritical fluid extraction (SFE) to remove petroleum hydrocarbons (PHCs) from two flare pit soils in Alberta. SFE is a technology for remediation of contaminated soils. In order to determine the optimal extraction conditions and to understand the effects of pressure, temperature, supercritical carbon dioxide flow rate, soil type, and extraction time on the extraction efficiency of SFE, extractions were performed on two flare pit soils at various pressures and temperatures. Chemicals in the study included diesel oil, SAE 10-30W motor oil, n-decane, hexadecane, tetratriacontane and pentacontane. The best extraction conditions were defined as conditions that result in a treated soil with a PHC concentration that meets the regulatory guidelines of the Canadian Council of Ministers of the Environment in the Canada-wide standard for PHC is soil. The study results indicate that the efficiency of the SFE process is solvent-density dependent for the conditions studied. The highest extraction efficiency for both soils was obtained at conditions of 24.1 MPa and 40 degrees C. An increase in pressure at a fixed temperature led to an increase in the extraction efficiency while an increase in temperature at a fixed pressure led to a decrease in the extraction efficiency. The treated soils were observed to be lighter in colour, drier, and grainier than the soil prior to extraction. It was concluded that SFE is an effective method for remediating flare pit soils. 63 refs., 4 tabs., 5 figs.

  19. Changes in soil organic carbon fractions after remediation of a coastal floodplain soil.

    Science.gov (United States)

    Wong, V N L; McNaughton, C; Pearson, A

    2016-03-01

    Coastal floodplain soils and wetland sediments can store large amounts of soil organic carbon (SOC). These environments are also commonly underlain by sulfidic sediments which can oxidise to form coastal acid sulfate soils (CASS) and contain high concentrations of acidity and trace metals. CASS are found on every continent globally except Antarctica. When sulfidic sediments are oxidised, scalds can form, which are large bare patches without vegetation. However, SOC stocks and fractions have not been quantified in these coastal floodplain environments. We studied the changes in soil geochemistry and SOC stocks and fractions three years after remediation of a CASS scald. Remediation treatments included raising water levels, and addition of either lime (LO) or lime and mulch (LM) relative to a control (C) site. We found SOC concentrations in the remediated sites (LO and LM) were more than double than that found at site C, reflected in the higher SOC stocks to a depth of 1.6 m (426 Mg C/ha, 478 Mg C/ha and 473 Mg C/ha at sites C, LO and LM, respectively). The particulate organic C (POC) fraction was higher at sites LO and LM due to increased vegetation and biomass inputs, compared to site C. Reformation of acid volatile sulfide (AVS) occurred throughout the profile at site LM, whereas only limited AVS reformation occurred at sites LO and C. Higher AVS at site LM may be linked to the additional source of organic matter provided by the mulch. POC can also potentially contribute to decreasing acidity as a labile SOC source for Fe(3+) and SO4(2-) reduction. Therefore, coastal floodplains and wetlands are a large store of SOC and can potentially increase SOC following remediation due to i) reduced decomposition rates with higher water levels and waterlogging, and ii) high C inputs due to rapid revegetation of scalded areas and high rates of biomass production. These results highlight the importance of maintaining vegetation cover in coastal floodplains and wetlands for

  20. Remediation of Wheat-Straw-Biochar on Petroleum-Polluted Soil

    Directory of Open Access Journals (Sweden)

    ZHU Wen-ying

    2014-06-01

    Full Text Available Biochar was made from wheat straw at 300 ℃ for 3, 6, 8 hours respectively. The productivity, pH, ash content and C, H, N content of these biochar were compared. The surface morphology of the 300 ℃-6 h biochar was characterized, and it was used to remediate the petroleum-polluted soil of Dagang oil field. Results showed that, as the extension of pyrolisis time, the productivity of biochar decreased, pH increased, ash content increased, H/C decreased. But productivity, pH, ash content and H/C changed significantly from 3 h to 6 h, unsignificantly from 6 h to 8 h. C content showed a downward trend after the first rise. After remediation of biochar for 14 and 28 days, the TPH degradation rate were 45.48% and 46.88% respectively, higher than control group. After 14 days remediation, content of naphthalene, acenaphthene, Benzo [a] anthracene, chrysene, Benzo [b] fluoranthene, Benzo [k] fluoranthene, Benzo [a] pyrene, Indene and [1,2,3-CD] pyrene were decreased to various degrees, with the Benzo [a] pyrene content decreased by 98.18%, and the degradation rate of other PAH higher than control group. After 28 days remediation however, content of these PAH showed a rising trend. It suggested that pyrolisis time had influence on biochar’ s characteristics, and 300 ℃-6 h biochar could be used to remediate petroleum-polluted soil.

  1. Remediation of arsenic-contaminated soils and groundwaters

    Science.gov (United States)

    Peters, Robert W.; Frank, James R.; Feng, Xiandong

    1998-01-01

    An in situ method for extraction of arsenic contaminants from a soil medium and remediation of the medium including contacting the medium with an extractant solution, directing the solution within and through the medium, and collecting the solution and contaminants. The method can also be used for arsenate and/or arsenite removal.

  2. Evaluation of contaminated soil remediation by low temperature thermal desorption

    International Nuclear Information System (INIS)

    Gibbs, L.; Punt, M.

    1993-01-01

    Soil contaminated with diesel and aviation fuels has been excavated and stored at a Canadian Forces Base in Ontario. Because of the volatile nature of this contamination, it was determined that low temperature thermal desorption (LTTD) would be an effective method of remediating this soil. A full scale evaluation of LTTD technology was conducted at the base to determine its acceptability for other sites. In the LTTD process, soil enters a primary treatment unit and is heated to a sufficiently high temperature to volatilize the hydrocarbon contaminants. Offgases are treated in a secondary combustion chamber. Primary treatment kiln temperature was maintained at 260 degree C for each test during the evaluation. The LTTD unit was evaluated for two sets of operating conditions: two levels of inlet soil total petroleum hydrocarbon concentrations and two feed rates (16,000 and 22,000 kg/h). Emissions from the LTTD unit were monitored continuously for volatile organics, moisture, and gas velocity. Results of the tests and emissions analyses are presented. Outlet soil hydrocarbon concentration requirements of 100 ppM were not exceeded during the evaluation. Air hydrocarbon emissions only exceeded 100-ppM limits under upset conditions, otherwise virturally no total hydrocarbon content was observed in the stack gas. 5 refs., 6 figs., 9 tabs

  3. Washing enhanced electrokinetic remediation for removal cadmium from real contaminated soil

    International Nuclear Information System (INIS)

    Giannis, Apostolos; Gidarakos, Evangelos

    2005-01-01

    The main objective of this study is to evaluate the combination of electrokinetic remediation and soil washing technology in order to remove cadmium from contaminated soil. This paper presents the results of an experimental research undertaken to evaluate different washing and purging solutions to enhance the removal of cadmium from a real contaminated soil during electrokinetic remediation. Two different experimental modules were applied in the laboratory. Soil was saturated with tap water, while acetic and hydrochloric acids, as well as ethylenediaminetetraacetic acid (EDTA) were used as purging solutions in the first module. Results show that there was a decrease of cadmium concentration near anode, but a significant increase in the middle of the cell, due to the increasing pH. Citric, nitric and acetic acids were used for soil washing and purging solutions in the second module. In this case, an 85% reduction of cadmium concentration was achieved. Therefore, results indicate that soil pH and washing solutions are the most important factors in governing the dissolution and/or desorption of Cd in a soil system under electrical fields

  4. Simulation of remediation alternatives for a 137Cs contaminated soil

    International Nuclear Information System (INIS)

    Bea, S.A.; Carrera, J.; Saaltink, M.; Soler, J.M.; Ayora, C.

    2004-01-01

    We analyze remediation alternatives for a soil contaminated with 137 Cs, which sorbs strongly to clay aggregates where water flux is negligible. The mobile portion of the soil (macropores) retains little water and cesium. Some of the remediation alternatives involve infiltration of seawater enriched with KCl, to promote mobilization of Cs through exchange with K. Therefore, a fully coupled reactive transport model is used to test these alternatives. We conclude that flushing is a viable alternative, provided that some recommendations, derived from the modelling exercise are followed. These include high rate periodic infiltration and draining, as well as performing infiltration from independent cells to limit the effect of preferential flowpaths. (orig.)

  5. Remediation approaches for polycyclic aromatic hydrocarbons (PAHs) contaminated soils: Technological constraints, emerging trends and future directions.

    Science.gov (United States)

    Kuppusamy, Saranya; Thavamani, Palanisami; Venkateswarlu, Kadiyala; Lee, Yong Bok; Naidu, Ravi; Megharaj, Mallavarapu

    2017-02-01

    For more than a decade, the primary focus of environmental experts has been to adopt risk-based management approaches to cleanup PAH polluted sites that pose potentially destructive ecological consequences. This focus had led to the development of several physical, chemical, thermal and biological technologies that are widely implementable. Established remedial options available for treating PAH contaminated soils are incineration, thermal conduction, solvent extraction/soil washing, chemical oxidation, bioaugmentation, biostimulation, phytoremediation, composting/biopiles and bioreactors. Integrating physico-chemical and biological technologies is also widely practiced for better cleanup of PAH contaminated soils. Electrokinetic remediation, vermiremediation and biocatalyst assisted remediation are still at the development stage. Though several treatment methods to remediate PAH polluted soils currently exist, a comprehensive overview of all the available remediation technologies to date is necessary so that the right technology for field-level success is chosen. The objective of this review is to provide a critical overview in this respect, focusing only on the treatment options available for field soils and ignoring the spiked ones. The authors also propose the development of novel multifunctional green and sustainable systems like mixed cell culture system, biosurfactant flushing, transgenic approaches and nanoremediation in order to overcome the existing soil- contaminant- and microbial-associated technological limitations in tackling high molecular weight PAHs. The ultimate objective is to ensure the successful remediation of long-term PAH contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Microorganisms in heavy metal bioremediation: strategies for applying microbial-community engineering to remediate soils

    OpenAIRE

    Jennifer L. Wood; Caixian Tang; Ashley E. Franks; Wuxing Liu

    2016-01-01

    The remediation of heavy-metal-contaminated soils is essential as heavy metals persist and do not degrade in the environment. Remediating heavy-metal-contaminated soils requires metals to be mobilized for extraction whilst, at the same time, employing strategies to avoid mobilized metals leaching into ground-water or aquatic systems. Phytoextraction is a bioremediation strategy that extracts heavy metals from soils by sequestration in plant tissues and is currently the predominant bioremediat...

  7. Electrokinetic remediation of anionic contaminants from unsaturated soils

    International Nuclear Information System (INIS)

    Lindgren, E.R.; Kozak, M.W.; Mattson, E.D.

    1992-01-01

    Heavy-metal contamination of soil and groundwater is a widespread problem in the DOE weapons complex, and for the nation as a whole. Electrokinetic remediation is one possible technique for in situ removal of such contaminants from unsaturated soils. In previous studies at Sandia National Laboratories, the electromigration of chromate ions and anionic dye ions have been demonstrated. This paper reports on a series of experiments that were conducted to study the effect of moisture content on the electromigration rate of anionic contaminants in unsaturated soil and determine the limiting moisture content for which electromigration occurs

  8. Combined Effects of Biochar and Fertilizer on Cadmium Contaminated Soil Remediation

    Directory of Open Access Journals (Sweden)

    WANG Qi-kai

    2015-12-01

    Full Text Available The field experiment was employed to study on the combined effects of biochar and chicken manure and N, P and K compound chemical fertilizer on cadmium contaminated soil remediation, and the immobilization mechanism was elucidated through fractionation of cadmium in the tested soil. Results showed that the addition of these ammendments could significantly reduce the edible Cd accumulation in Lactuca sativa L., decreased from 32.6% to 54.8% compared with the control. The application of these additives could also significantly decrease extractable Cd concentration by 7.04%~21.85%. Biochar could significantly improve soil pH value, promote the inactivation of Cd contaminated soil, while the application of chicken manure significantly decreased soil pH value, which showed the effect of activating Cd in soil. Soil pH value had significant positive correlation with root Cd concentration of tested cultivars, but did not reach the significant effect level with the shoot Cd concentration. The research can provide a theoretical basis for the application of biochar combined with chicken manure and N, P and K compound chemical fertilizer on remediation of sewage irrigated Cd contaminated soil.

  9. Screening of fungi for soil remediation potential

    Science.gov (United States)

    Richard T. Lamar; Laura M. Main; Diane M. Dietrich; John A. Glaser

    1999-01-01

    The purpose of the present investigation was to determine if physiological and/or biochemical factors such as growth rate, tolerance to and ability to degrade PCP or creosote have use for predicting the potential bioremediation performance of fungi. Because we have focused the initial development of a fungal-based soil remediation technology on PCP- and/or creosote-...

  10. Remediation of petroleum contaminated soils through bioventing in cold regions

    International Nuclear Information System (INIS)

    Brar, G.S.; Currier, P.M.; Reynolds, C.M.; Millhouse, J.B.

    1994-01-01

    Petroleum contaminated soils are found in many remote sites in Alaska where releases from bulk storage of fuel oil for heat and power generation have occurred. Bioventing, a process in which petroleum degradation by indigenous aerobic bacteria is enhanced by supplying oxygen and nutrients, may be a viable treatment technique for soils at remote sites if limitations due to low temperatures can be overcome. The objectives of this study were to: (1) test a design for ex-situ bioventing in cold regions, (2) evaluate biodegradation rates at low temperatures, and (3) determine the effects of applied nutrients on low-temperature biodegradation. Two aerated biopit remediation cells were constructed to treat previously excavated soils at Eareckson Air Force Station, Shemya, Alaska. Experimental treatments consisted of a fertilized pile (FP) and a nonfertilized pile (NFP). Hourly soil and air temperature data at 4 depths were recorded at 4 locations in each biopit. During 148 days of remediation, mean temperature ranged from -3 to 6 C for air at 100 cm. above the piles. The mean concentrations of TPH and DRO decreased from an initial 1,304 and 982 mg/kg of 139 and 82 mg/kg, respectively, with the FP, and 422 and 294 mg/kg with the NFP in 115 days. Cumulative degradation rates of TPH and DRO are significantly (P 2 = 0.94 for TPH. 0.93 for DRO). Pit bioventing technology was shown to be efficient, fast, and cost-effective in cold regions where temperature during winter months is a major constraint for the remediation of contaminated soils

  11. Flotation and remediation of contaminated sludge and soil

    NARCIS (Netherlands)

    Koopal, L.K.; Mulleneers, H.A.E.

    2003-01-01

    Flotation, traditionally applied in mineralogy, has been used more recently in wastewater treatment, soil and sediment remediation and paper de-inking. The latter types of application may differ from mineral separation by the fact that the particles that should be floated are often partially

  12. Effects of remediation train sequence on decontamination of heavy metal-contaminated soil containing mercury.

    Science.gov (United States)

    Hseu, Zeng-Yei; Huang, Yu-Tuan; Hsi, Hsing-Cheng

    2014-09-01

    When a contaminated site contains pollutants including both nonvolatile metals and Hg, one single remediation technology may not satisfactorily remove all contaminants. Therefore, in this study, chemical extraction and thermal treatment were combined as a remediation train to remove heavy metals, including Hg, from contaminated soil. A 0.2 M solution of ethylenediamine tetraacetic acid (EDTA) was shown to be the most effective reagent for extraction of considerable amounts of Cu, Pb, and Zn (> 50%). Hg removal was ineffective using 0.2 M EDTA, but thermogravimetric analysis suggested that heating to 550 degrees C with a heating rate of 5 degrees C/min for a duration of 1 hr appeared to be an effective approach for Hg removal. With the employment of thermal treatment, up to 99% of Hg could be removed. However executing thermal treatment prior to chemical extraction reduced the effectiveness of the subsequent EDTA extraction because nonvolatile heavy metals were immobilized in soil aggregates after the 550 degrees C treatment. The remediation train of chemical extraction followed by thermal treatment appears to remediate soils that have been contaminated by many nonvolatile heavy metals and Hg. Implications: A remediation train conjoining two or more techniques has been initialized to remove multiple metals. Better understandings of the impacts of treatment sequences, namely, which technique should be employed first on the soil properties and the decontamination efficiency, are in high demand. This study provides a strategy to remove multiple heavy metals including Hg from a contaminated soil. The interactions between thermal treatment and chemical extraction on repartitioning of heavy metals was revealed. The obtained results could offer an integrating strategy to remediate the soil contaminated with both heavy metals and volatile contaminants.

  13. Biochar based remediation of water and soil contaminated by phenanthrene and pentachlorophenol.

    Science.gov (United States)

    Rao, Maria A; Di Rauso Simeone, Giuseppe; Scelza, Rosalia; Conte, Pellegrino

    2017-11-01

    Phenanthrene (Phe) and pentachlorophenol (PCP) are classified as persistent organic pollutants and represent serious concern for the environment as they are toxic and ubiquitous. Biochar based remediation is an emerging technology used in water and soil contamination. In this study we used poplar (BP) and conifer (BC) biochars to remediate water and soil contaminated by Phe and PCP. BP and BC were able to remove completely either Phe or PCP from contaminated water within one to three days. When biochar was confined in a porous membrane, BC and BP maintained their sorption efficiency for several remediation cycles. However, in these conditions BC allowed faster Phe removal. In soil remediation experiments, addition of two biochar rates, i.e. 2.5 and 5 mg g -1 , strongly reduced Phe extractability (up to 2.7% of the initially added Phe with the larger BC dose). This was similar to the behavior observed when compost was applied in order to verify the role of soil organic matter in the fate of both contaminants. PCP extractability was reduced only up to 75% (in average) in all samples including those with compost amendment. Only larger amount of biochar (20 and 50 mg g -1 ) allowed reduction of the extractable PCP and nullified phytotoxicity of the contaminant. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. The effect of earthworms on the fractionation and bioavailability of heavy metals before and after soil remediation

    International Nuclear Information System (INIS)

    Udovic, Metka; Lestan, Domen

    2007-01-01

    The effect of two earthworm species, Lumbricus rubellus and Eisenia fetida, on the fractionation/bioavailability of Pb and Zn before and after soil leaching with EDTA was studied. Four leaching steps with total 12.5 mmol kg -1 EDTA removed 39.8% and 6.1% of Pb and Zn, respectively. EDTA removed Pb from all soil fractions fairly uniformly (assessed using sequential extractions). Zn was mostly present in the chemically inert residual soil fraction, which explains its poor removal. Analysis of earthworm casts and the remainder of the soil indicated that L. rubellus and E. fetida actively regulated soil pH, but did not significantly change Pb and Zn fractionation in non-remediated and remediated soil. However, the bioavailability of Pb (assessed using Ruby's physiologically based extraction test) in E. fetida casts was significantly higher than in the bulk of the soil. In remediated soil the Pb bioavailability in the simulated stomach phase increased by 5.1 times. - Earthworm activity increases heavy metal bioavailability in soil before and after remediation

  15. The effect of earthworms on the fractionation and bioavailability of heavy metals before and after soil remediation

    Energy Technology Data Exchange (ETDEWEB)

    Udovic, Metka [Agronomy Department, Centre for Soil and Environmental Science, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana (Slovenia); Lestan, Domen [Agronomy Department, Centre for Soil and Environmental Science, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana (Slovenia)]. E-mail: domen.lestan@bf.uni-lj.si

    2007-07-15

    The effect of two earthworm species, Lumbricus rubellus and Eisenia fetida, on the fractionation/bioavailability of Pb and Zn before and after soil leaching with EDTA was studied. Four leaching steps with total 12.5 mmol kg{sup -1} EDTA removed 39.8% and 6.1% of Pb and Zn, respectively. EDTA removed Pb from all soil fractions fairly uniformly (assessed using sequential extractions). Zn was mostly present in the chemically inert residual soil fraction, which explains its poor removal. Analysis of earthworm casts and the remainder of the soil indicated that L. rubellus and E. fetida actively regulated soil pH, but did not significantly change Pb and Zn fractionation in non-remediated and remediated soil. However, the bioavailability of Pb (assessed using Ruby's physiologically based extraction test) in E. fetida casts was significantly higher than in the bulk of the soil. In remediated soil the Pb bioavailability in the simulated stomach phase increased by 5.1 times. - Earthworm activity increases heavy metal bioavailability in soil before and after remediation.

  16. Selective separation of very small particles by flotation : in relation to soil and sediment remediation

    NARCIS (Netherlands)

    Mulleneers, H.

    2001-01-01

    Next to numerous contaminated sites, also large quantities of polluted dredged sediments have to be cleaned in the near future in the Netherlands. Soil washing (classification) is one of the most common remediation techniques to remediate contaminated dredged sediment and excavated soil. It uses

  17. Phytoavailability and geospeciation of cadmium in contaminated soil remediated by Rhodobacter sphaeroides.

    Science.gov (United States)

    Fan, Wenhong; Jia, Yingying; Li, Xiaomin; Jiang, Wei; Lu, Lin

    2012-07-01

    A microorganism was isolated from oil field injection water and identified as Rhodobacter sphaeroides. It was used for the remediation of simulated cadmium-contaminated soil. The phytoavailability of Cd was investigated through wheat seedling method to determine the efficiency of remediation. It was found that after remediation, the accumulation of Cd in wheat roots and leaves decreased by 67% and 53%, respectively. The Cd speciation in soil was determined with Tessier extraction procedure. It was found that the total Cd content in soil did not change during the experiments, but the geo-speciation of Cd changed remarkably. Among the five fractions, the concentration of exchangeable phases decreased by 27-46% and that of the phases bound to Fe-Mn oxides increased by 22-44%. The decrease of Cd accumulation in wheat showed significant positive correlation with the decrease of exchangeable phases. It could be concluded that the remediation of R. sphaeroides was carried out through the conversion of Cd to more stable forms. The decrease of sulfate concentration in supernatant indicated that the R. sphaeroides consumed sulfate. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Development of methods for remediation of artificial polluted soils and improvement of soils for ecologically clean agricultural production systems

    International Nuclear Information System (INIS)

    Bogachev, V.; Adrianova, G.; Zaitzev, V.; Kalinin, V.; Kovalenko, E.; Makeev, A.; Malikova, L.; Popov, Yu.; Savenkov, A.; Shnyakina, V.

    1996-01-01

    The purpose of the research: Development of methods for the remediation of artificial polluted soils and the improvement of polluted lands to ecologically clean agricultural production.The following tasks will be implemented in this project to achieve viable practical solutions: - To determine the priority pollutants, their ecological pathways, and sources of origin. - To form a supervised environmental monitoring data bank throughout the various geo system conditions. - To evaluate the degree of the bio geo system pollution and the influence on the health of the local human populations. - To establish agricultural plant tolerance levels to the priority pollutants. - To calculate the standard concentrations of the priority pollutants for main agricultural plant groups. - To develop a soil remediation methodology incorporating the structural, functional geo system features. - To establish a territory zone division methodology in consideration of the degree of component pollution, plant tolerance to pollutants, plant production conditions, and human health. - Scientific grounding of the soil remediation proposals and agricultural plant material introductions with soil pollution levels and relative plant tolerances to pollutants. Technological Means, Methods, and Approaches Final proposed solutions will be based upon geo system and ecosystem approaches and methodologies. The complex ecological valuation methods of the polluted territories will be used in this investigation. Also, laboratory culture in vitro, application work, and multi-factor field experiments will be conducted. The results will be statistically analyzed using appropriate methods. Expected Results Complex biogeochemical artificial province assessment according to primary pollutant concentrations. Development of agricultural plant tolerance levels relative to the priority pollutants. Assessment of newly introduced plant materials that may possess variable levels of pollution tolerance. Remediation

  19. Proceedings (of the) first annual groundwater and soil remediation R, D and D (research, development and demonstration) symposium

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    A symposium was held to present results of research on the remediation of contamination of groundwater and soils. Papers were presented on groundwater/soil remediation research and demonstration programs, in-situ bioremediation, remediation of groundwater contaminated by gasoline-derived aromatics, solvent extraction of petroleum hydrocarbons from soil, bioreactors for cleaning hydrocarbon- and salt-contaminated soils, in-situ volatilization technologies, evaluations of spill cleanup technologies, remediating subsurface contamination around sour gas processing plants, and the influence of gasoline oxygenates on the persistence of aromatics in groundwater. Separate abstracts have been prepared for 9 papers from this symposium.

  20. Remediation of hexavalent chromium spiked soil by using synthesized iron sulfide particles.

    Science.gov (United States)

    Li, Yujie; Wang, Wanyu; Zhou, Liqiang; Liu, Yuanyuan; Mirza, Zakaria A; Lin, Xiang

    2017-02-01

    Carboxymethyl cellulose (CMC) stabilized microscale iron sulfide (FeS) particles were synthesized and applied to remediate hexavalent chromium (Cr(VI)) spiked soil. The effects of parameters including dosage of FeS particles, soil moisture, and natural organic matter (NOM) in soil were investigated with comparison to iron sulfate (FeSO 4 ). The results show that the stabilized FeS particles can reduce Cr(VI) and immobilize Cr in soil quickly and efficiently. The soil moisture ranging from 40% to 70% and NOM in soil had no significant effects on Cr(VI) remediation by FeS particles. When molar ratio of FeS to Cr(VI) was 1.5:1, about 98% of Cr(VI) in soil was reduced by FeS particles in 3 d and Cr(VI) concentration decreased from 1407 mg kg -1 to 16 mg kg -1 . The total Cr and Cr(VI) in Toxicity Characteristic Leaching Procedure (TCLP) leachate were reduced by 98.4% and 99.4%, respectively. In FeS particles-treated soil, the exchangeable Cr fraction was mainly converted to Fe-Mn oxides bound fraction because of the precipitation of Cr(III)-Fe(III) hydroxides. The physiologically based extraction test (PBET) bioaccessibility of Cr was decreased from 58.67% to 6.98%. Compared to FeSO 4 , the high Cr(VI) removal and Cr immobilization efficiency makes prepared FeS particles a great potential in field application of Cr(VI) contaminated soil remediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. In situ remediation and phytotoxicity assessment of lead-contaminated soil by biochar-supported nHAP.

    Science.gov (United States)

    Yang, Zhangmei; Fang, Zhanqiang; Tsang, Pokeung Eric; Fang, Jianzhang; Zhao, Dongye

    2016-11-01

    In this study, a kind of biochar-supported nano-hydroxyapatite (nHAP@BC) material was used in in-situ remediation of lead-contaminated soil. Column experiments were performed to compare the mobility of nHAP@BC and Bare-nHAP. The immobilization, accumulation and toxic effects of Pb in the after-amended soil were assessed by the in vitro toxicity tests and pot experiments. The column experiments showed a significant improvement in the mobility of nHAP@BC. The immobilization rate of Pb in the soil was 74.8% after nHAP@BC remediation. Sequential extraction procedures revealed that the residual fraction of Pb increased by 66.6% after nHAP@BC remediation, which greatly reduced the bioavailability of Pb in the soil. In addition, pot experiments indicated that nHAP@BC could effectively reduce the upward translocation capacity of Pb in a soil-plant system. The concentration of Pb in the aerial part of the cabbage mustard was 0.1 mg/kg, which is lower than the tolerance limit (0.3 mg/kg). nHAP@BC can remediate Pb-contaminated soil effectively, which can restore soil quality for planting. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. The Reconstituited Soils: The Technology and Its Possible Implementation in the Remediation of Contaminated Soils

    OpenAIRE

    Paolo Adriano Manfredi

    2016-01-01

    Reconstitution technology is a pedotechnique whose action supplements soil structure with organic and mineral components that are quality and origin certified. The treatment procedure performs a mechanical action which forms an organic matter lining within the mineral fraction by means of soil structure disintegration and subsequent reconstitution. Results produced by the technology in the field of agronomy suggest that such method may be employed to remediate contaminated soil by altering it...

  3. Review of chemical and electrokinetic remediation of PCBs contaminated soils and sediments.

    Science.gov (United States)

    Fan, Guangping; Wang, Yu; Fang, Guodong; Zhu, Xiangdong; Zhou, Dongmei

    2016-09-14

    Polychlorinated biphenyls (PCBs) are manmade organic compounds, and pollution due to PCBs has been a global environmental problem because of their persistence, long-range atmospheric transport and bioaccumulation. Many physical, chemical and biological technologies have been utilized to remediate PCBs contaminated soils and sediments, and there are some emerging new technologies and combined methods that may provide cost-effective alternatives to the existing remediation practice. This review provides a general overview on the recent developments in chemical treatment and electrokinetic remediation (EK) technologies related to PCBs remediation. In particular, four technologies including photocatalytic degradation of PCBs combined with soil washing, Fe-based reductive dechlorination, advanced oxidation process, and EK/integrated EK technology (e.g., EK coupled with chemical oxidation, nanotechnology and bioremediation) are reviewed in detail. We focus on the fundamental principles and governing factors of chemical technologies, and EK/integrated EK technologies. Comparative analysis of these technologies including their major advantages and disadvantages is summarized. The existing problems and future prospects of these technologies regarding PCBs remediation are further highlighted.

  4. Role of biochar on composting of organic wastes and remediation of contaminated soils-a review.

    Science.gov (United States)

    Wu, Shaohua; He, Huijun; Inthapanya, Xayanto; Yang, Chunping; Lu, Li; Zeng, Guangming; Han, Zhenfeng

    2017-07-01

    Biochar is produced by pyrolysis of biomass residues under limited oxygen conditions. In recent years, biochar as an amendment has received increasing attention on composting and soil remediation, due to its unique properties such as chemical recalcitrance, high porosity and sorption capacity, and large surface area. This paper provides an overview on the impact of biochar on the chemical characteristics (greenhouse gas emissions, nitrogen loss, decomposition and humification of organic matter) and microbial community structure during composting of organic wastes. This review also discusses the use of biochar for remediation of soils contaminated with organic pollutants and heavy metals as well as related mechanisms. Besides its aging, the effects of biochar on the environment fate and efficacy of pesticides deserve special attention. Moreover, the combined application of biochar and compost affects synergistically on soil remediation and plant growth. Future research needs are identified to ensure a wide application of biochar in composting and soil remediation. Graphical abstract ᅟ.

  5. Microbial Fuel Cells for Organic-Contaminated Soil Remedial Applications

    NARCIS (Netherlands)

    Li, Xiaojing; Wang, Xin; Weng, Liping; Zhou, Qixing; Li, Yongtao

    2017-01-01

    Efficient noninvasive techniques are desired for repairing organic-contaminated soils. Bioelectrochemical technology, especially microbial fuel cells (MFCs), has been widely used to promote a polluted environmental remediation approach, and applications include wastewater, sludge, sediment, and

  6. Remediation of Cd(II)-contaminated soil via humin-enhanced electrokinetic technology.

    Science.gov (United States)

    Ding, Ling; Lv, Wenying; Yao, Kun; Li, Liming; Wang, Mengmeng; Liu, Guoguang

    2017-02-01

    Humin is the component of humic substances that is recalcitrant to extraction by either strong bases or strong acids, which contains a variety of functional groups that may combine with heavy metal ions. The present study employed humin as an adsorbent to investigate the efficacy of a remediation strategy under the effects of humin-enhanced electrokinetics. Because the cations gravitate toward cathode and anions are transferred to anode, humin was placed in close proximity to the cathode in the form of a package. The humin was taken out after the experiments to determine whether a target pollutant (cadmium) might be completely removed from soil. Acetic acid-sodium acetate was selected as the electrolyte for these experiments, which was circulated between the two electrode chambers via a peristaltic pump, in order to control the pH of the soil. The results indicated that when the remediation duration was extended to 240 h, the removal of acid extractable Cd(II) could be up to 43.86% efficiency, and the adsorption of the heavy metal within the humin was 86.15 mg/kg. Further, the recycling of the electrolyte exhibited a good control of the pH of the soil. When comparing the pH of the soil with the circulating electrolyte during remediation, in contrast to when it was not being recycled, the pH of the soil at the anode increased from 3.89 to 5.63, whereas the soil at the cathode decreased from 8.06 to 7.10. This indicated that the electrolyte recycling had the capacity to stabilize the pH of the soil.

  7. Assessment of produced water contaminated soils to determine remediation requirements

    International Nuclear Information System (INIS)

    Clodfelter, C.

    1995-01-01

    Produced water and drilling fluids can impact the agricultural properties of soil and result in potential regulatory and legal liabilities. Produced water typically is classified as saline or a brine and affects surface soils by increasing the sodium and chloride content. Sources of produced water which can lead to problems include spills from flowlines and tank batteries, permitted surface water discharges and pit areas, particularly the larger pits including reserve pits, emergency pits and saltwater disposal pits. Methods to assess produced water spills include soil sampling with various chemical analyses and surface geophysical methods. A variety of laboratory analytical methods are available for soil assessment which include electrical conductivity, sodium adsorption ratio, cation exchange capacity, exchangeable sodium percent and others. Limiting the list of analytical parameters to reduce cost and still obtain the data necessary to assess the extent of contamination and determine remediation requirements can be difficult. The advantage to using analytical techniques is that often regulatory remediation standards are tied to soil properties determined from laboratory analysis. Surface geophysical techniques can be an inexpensive method to rapidly determine the extent and relative magnitude of saline soils. Data interpretations can also provide an indication of the horizontal as well as the vertical extent of impacted soils. The following discussion focuses on produced water spills on soil and assessment of the impacted soil. Produced water typically contains dissolved hydrocarbons which are not addressed in this discussion

  8. Characterization and remediation of soil prior to construction of an on-site disposal facility at Fernald

    International Nuclear Information System (INIS)

    Hunt, A.; Jones, G.; Nelson, K.

    1998-03-01

    During the production years at the Feed Materials Production Center (FMPC), the soil of the site and the surrounding areas was surficially impacted by airborne contamination. The volume of impacted soil is estimated at 2.2 million cubic yards. During site remediation, this contamination will be excavated, characterized, and disposed of. In 1986 the US Environmental Protection Agency (EPA) and the Department of Energy (DOE) entered into a Federal Facility Compliance Agreement (FFCA) covering environmental impacts associated with the FMPC. A site wide Remedial Investigation/Feasibility Study (RI/FS) was initiated pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act, as amended by the Superfund Amendments and Reauthorization Act (CERCLA). The DOE has completed the RI/FS process and has received approval of the final Records of Decision. The name of the facility was changed to the Fernald Environmental Management Project (FEMP) to emphasize the change in mission to environmental restoration. Remedial actions which address similar scopes of work or types of contaminated media have been grouped into remedial projects for the purpose of managing the remediation of the FEMP. The Soil Characterization and Excavation Project (SCEP) will address the remediation of FEMP soils, certain waste units, at- and below-grade material, and will certify attainment of the final remedial limits (FRLs) for the FEMP. The FEMP will be using an on-site facility for low level radioactive waste disposal. The facility will be an above-ground engineered structure constructed of geological material. The area designated for construction of the base of the on-site disposal facility (OSDF) is referred to as the footprint. Contaminated soil within the footprint must be identified and remediated. Excavation of Phase 1, the first of seven remediation areas, is complete

  9. Remediation of trichloroethylene-contaminated soils by star technology using vegetable oil smoldering

    OpenAIRE

    Salman, Madiha; Gerhard, Jason I.; Major, David W.; Pironi, Paolo; Hadden, Rory

    2015-01-01

    Self-sustaining treatment for active remediation (STAR) is an innovative soil remediation approach based on smoldering combustion that has been demonstrated to effectively destroy complex hydrocarbon nonaqueous phase liquids (NAPLs) with minimal energy input. This is the first study to explore the smoldering remediation of sand contaminated by a volatile NAPL (trichloroethylene, TCE) and the first to consider utilizing vegetable oil as supplemental fuel for STAR. Thirty laboratory-scale exper...

  10. Phytoextraction and estimating optimal time for remediation of Cd-contaminated soils by Spinach

    Directory of Open Access Journals (Sweden)

    Somayyeh Eisazadeh Lazarjan

    2016-05-01

    Full Text Available The so-called phytoextraction in which hyperaccumulator plants are used to remediate the contaminated soils is proven to be an efficient method. The objective of this study was to investigate the capability of Spinach for phytoremediation of cadmium from Cd-contaminated soils and determine the efficiency extent of spinach for phytoremediation. For this purpose, a randomized block experimental design whit five treatments including 0, 15, 30, 60 and 120 mg Cd/ kg soil and three replications was established in the greenhouse. After contamination the soils with different levels of cadmium, spinach seeds were planted. When plants were fully developed, plants were harvested and their cadmium contents in shoot and roots as well as the soil-cadmium were measured. The results indicated that by increasing Cd concentration in soil, the major Cd accumulation was occurred in the roots rather than shoots. Maximum cadmium concentration within the shoots and roots was 73.7 and 75.86 mg/kg soil, respectively. According to Spinach ability to absorb high concentration of cadmium in the root zone and its high biomass and capability of Cadmium accumulation in shoots, Spinach can be used as hyperaccumulator plant to remediate cadmium from Cd-contaminated soils. But, according to minimum remediation time and maximum dry matter for the 30 mg Cd/ kg soil, maximum Cd extracted by shoots in hectare/year was in 30 mg Cd/ kg soil. It can be concluded that Spinach is a suitable plant for phytoremediation of slightly and to moderately cadmium contaminated soils.

  11. Heavy Metal Phytoremediation: Microbial Indicators of Soil Health for the Assessment of Remediation Efficiency

    Science.gov (United States)

    Epelde, Lur; Ma Becerril, José; Alkorta, Itziar; Garbisu, Carlos

    Phytoremediation is an effective, non-intrusive, inexpensive, aesthetically pleasing, socially accepted, promising phytotechnology for the remediation of polluted soils. The objective of any soil remediation process must be not only to remove the contaminant(s) from the soil but, most importantly, to restore the continued capacity of the soil to perform or function according to its potential (i.e., to recover soil health). Hence, indicators of soil health are needed to properly assess the efficiency of a phytoremediation process. Biological indicators of soil health, especially those related to the size, activity and diversity of the soil microbial communities, are becoming increasingly used, due to their sensitivity and capacity to provide information that integrates many environmental factors. In particular, microbial indicators of soil health are valid tools to evaluate the success of metal phytoremediation procedures such as phytoextraction and phytostabilization processes.

  12. In situ remediation-released zero-valent iron nanoparticles impair soil ecosystems health: A C. elegans biomarker-based risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ying-Fei; Cheng, Yi-Hsien; Liao, Chung-Min, E-mail: cmliao@ntu.edu.tw

    2016-11-05

    Highlights: • Fe{sup 0} NPs induced infertility risk in C. elegans. • A C.elegans-based probabilistic risk assessment model is developed. • In situ remediation-released Fe{sup 0} NPs impair soil ecosystems health. - Abstract: There is considerable concern over the potential ecotoxicity to soil ecosystems posed by zero-valent iron nanoparticles (Fe{sup 0} NPs) released from in situ environmental remediation. However, a lack of quantitative risk assessment has hampered the development of appropriate testing methods used in environmental applications. Here we present a novel, empirical approach to assess Fe{sup 0} NPs-associated soil ecosystems health risk using the nematode Caenorhabditis elegans as a model organism. A Hill-based dose-response model describing the concentration–fertility inhibition relationships was constructed. A Weibull model was used to estimate thresholds as a guideline to protect C. elegans from infertility when exposed to waterborne or foodborne Fe{sup 0} NPs. Finally, the risk metrics, exceedance risk (ER) and risk quotient (RQ) of Fe{sup 0} NPs in various depths and distances from remediation sites can then be predicted. We showed that under 50% risk probability (ER = 0.5), upper soil layer had the highest infertility risk (95% confidence interval: 13.18–57.40%). The margins of safety and acceptable criteria for soil ecosystems health for using Fe{sup 0} NPs in field scale applications were also recommended. Results showed that RQs are larger than 1 in all soil layers when setting a stricter threshold of ∼1.02 mg L{sup −1} of Fe{sup 0} NPs. This C. elegans biomarker-based risk model affords new insights into the links between widespread use of Fe{sup 0} NPs and environmental risk assessment and offers potential environmental implications of metal-based NPs for in situ remediation.

  13. Kinetics as a tool to assess the immobilization of soil trace metals by binding phase amendments for in situ remediation purposes

    International Nuclear Information System (INIS)

    Varrault, Gilles; Bermond, Alain

    2011-01-01

    Highlights: → Assessment of the efficiency of soil remediation method by binding phase amendment. → Use of a kinetic fractionation method to assess trace metal mobility in amended soils. → Vernadite amendments are effective for lead and cadmium remediation. → IHA amendments are only effective for copper remediation. → Advantages of kinetic fractionation vs. extraction schemes performed at equilibrium. - Abstract: Many soil remediation techniques consist in decreasing the mobility of trace metals by means of adding trace metal binding phases. For this study, whose aim is to assess the efficiency of soil remediation method by binding phase amendment, a kinetic fractionation method that provides the labile and slowly labile trace metal amounts in soil has been introduced. Manganese oxides (vernadite) and insolubilized humic acids (IHA) have been used as binding phases for the remediation of four heavily polluted soils. Vernadite amendments are effective for lead and cadmium remediation, whereas IHA amendments are only effective for copper remediation. In most cases, the labile metal fractions decrease dramatically in amended soils (up to 50%); on the other hand, the amounts of total extracted metal near the point of thermodynamic equilibrium often show no significant difference between the amended soil and the control soil. These results highlight the utility of kinetic fractionation in assessing the efficiency of soil remediation techniques and, more generally, in evaluating trace metal mobility in soils and its potential advantages compared to extraction schemes performed under equilibrium conditions. In the future, this kinetic method could be considerably simplified so as to consume much less time allowing its routine use.

  14. Bioventing - a new twist on soil vapor remediation of the vadose zone and shallow ground water

    International Nuclear Information System (INIS)

    Yancheski, T.B.; McFarland, M.A.

    1992-01-01

    Bioventing, which is a combination of soil vapor remediation and bioremediation techniques, may be an innovative, cost-effective, and efficient remedial technology for addressing petroleum contamination in the vadose zone and shallow ground water. The objective of bioventing is to mobilize petroleum compounds from the soil and ground water into soil vapor using soil vapor extraction and injection technology, and to promote the migration of the soil vapor upward to the turf root zone for degradation by active near-surface microbiological activity. Promoting and maintaining optimum microbiological activity in the turf root rhizosphere is a key component to the bioventing technique. Preliminary ongoing USEPA bioventing pilot studies (Kampbell, 1991) have indicated that this technique is a promising remediation technology, although feasibility studies are not yet complete. However, based on the preliminary data, it appears that proper bioventing design and implementation will result in substantial reductions of petroleum compounds in the capillary zone and shallow ground water, complete degradation of petroleum compounds in the turf root zone, and no surface emissions. A bioventing system was installed at a site in southern Delaware with multiple leaking underground storage tanks in early 1992 to remediate vadose zone and shallow ground-water contaminated by petroleum compounds. The system consists of a series of soil vapor extraction and soil vapor/atmospheric air injection points placed in various contamination areas and a central core remediation area (a large grassy plot). This system was chosen for this site because it was least costly to implement and operate as compared to other remedial alternatives (soil vapor extraction with carbon or catalytic oxidation of off-gas treatment, insitu bioremediation, etc.), and results in the generation of no additional wastes

  15. Use of plant and earthworm bioassays to evaluate remediation of soil from a site contaminated with polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Meier, J.R.; Chang, L.W.; Meckes, M.C.; Smith, M.K. [Environmental Protection Agency, Cincinnati, OH (United States); Jacobs, S. [DynCorp, Cincinnati, OH (United States); Torsella, J. [Oak Ridge Inst. of Science and Education, Cincinnati, OH (United States)

    1997-05-01

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The earthworm toxicity bioassays were the 14-d survival test and 21-d reproduction test, using Lumbricus terrestris and Eisenia fetida andrei. The plant bioassays included phytotoxicity tests for seed germination and root elongation in lettuce and oats, and a genotoxicity test (anaphase aberrations) in Allium cepa (common onion). Although the PCB content of the soil was reduced by 99% (below the remediation goal), toxicity to earthworm reproduction remained essentially unchanged following remediation. Furthermore, phytotoxicity and genotoxicity were higher for the remediated soil compared to the untreated soil. The toxicity remaining after treatment appeared to be due to residual solvent introduced during the remediation process, and/or to heavy metals or other inorganic contaminants not removed by the treatment. Mixture studies involving isopropanol and known toxicants indicated possible synergistic effects of the extraction solvent and soil contaminants. The toxicity in plants was essentially eliminated by a postremediation, water-rinsing step. These results demonstrate a need for including toxicity measurements in the evaluation of technologies used in hazardous waste site remediations, and illustrate the potential value of such measurements for making modifications to remediation processes.

  16. The possible use of soluble humic substances for remediation of heavy metal polluted soils

    DEFF Research Database (Denmark)

    Borggaard, Ole K.; Jensen, Julie Katrine; Holm, Peter Engelund

    2008-01-01

    Polluted soil is a common and serious environmental problem. While reliable methods exist for cleaning soil contaminated by organic compounds through degradation, remediation of heavy metal polluted soils awaits an appropriate solution. This is because heavy metals are nondegradable and generally....... Therefore, the potential of soluble natural humic substances (HS) to extract heavy metals from contaminated soils is tested as an environmental friendly substitute for EDTA. A strongly polluted urban soil and a moderately polluted agricultural soil were extracted at neutral pH in batch mode by three HS...... extraction. Heavy metal extraction with dissolved HS is compared with EDTA at the same concentration and sequential extraction has been performed to identify extracted pools. The results indicate a clear potential of using HS solutions for remediation of heavy metal polluted soils, which is fortunate...

  17. DECHEM: A remedial planning tool for metallic contaminants in soil at UMTRA Project sites

    International Nuclear Information System (INIS)

    1989-03-01

    The DECHEM (DEcontamination of CHEMicals) method was developed for the Uranium Mill Tailings Remedial Action (UMTRA) Project to guide characterization and remedial planning for metals contamination in soils. This is necessary because non-radiological hazardous constituents may be more mobile than radium-226 (Ra-226), and hence may migrate more deeply into subpile soils (beneath tailings that are to be relocated) or into adjacent contaminated soils at UMTRA Project sites. The result is that remedial action to the Ra-226 excavation limit, as specified in the US Environmental Protection Agency (EPA) standards, may not adequately remove hazardous non-radiological contamination. Unmitigated, these contaminants in soil may cause health risks because of their presence in resuspended particles, their uptake by crops or fodder their seepage into aquifers used for drinking water or other possible exposure pathways. The DECHEM method was developed in response to the need for advanced planning for the remediation of chemical contaminants at UMTRA Project sites, and includes the following elements: Establishment of acceptable exposure rates for humans to chemicals, based on EPA guidelines or other toxicological literature. Modeling of chemical migration through environmental pathways from a remediated UMTRA Project site to humans. Determination of allowable residual concentrations (i.e., cleanup guidelines) for chemicals in soils that results in doses to humans that are below established acceptable exposure rates. The initial development and application of the DECHEM method has focused upon hazardous metallic contaminants such as arsenic, lead, molybdenum, and selenium, which are known to occur in elevated concentrations at some UMTRA Project sites

  18. Remediation of Diesel Fuel Contaminated Sandy Soil using Ultrasonic Waves

    Directory of Open Access Journals (Sweden)

    Wulandari P.S.

    2010-01-01

    Full Text Available Ultrasonic cleaning has been used in industry for some time, but the application of ultrasonic cleaning in contaminated soil is just recently received considerable attention, it is a very new technique, especially in Indonesia. An ultrasonic cleaner works mostly by energy released from the collapse of millions of microscopic cavitations near the dirty surface. This paper investigates the use of ultrasonic wave to enhance remediation of diesel fuel contaminated sandy soil considering the ultrasonic power, soil particle size, soil density, water flow rate, and duration of ultrasonic waves application.

  19. The Reconstituited Soils: The Technology and Its Possible Implementation in the Remediation of Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Paolo Adriano Manfredi

    2016-11-01

    Full Text Available Reconstitution technology is a pedotechnique whose action supplements soil structure with organic and mineral components that are quality and origin certified. The treatment procedure performs a mechanical action which forms an organic matter lining within the mineral fraction by means of soil structure disintegration and subsequent reconstitution. Results produced by the technology in the field of agronomy suggest that such method may be employed to remediate contaminated soil by altering its properties according to need.

  20. [Effect of different soil types on the remediation of copper-pyrene compound contaminated soils by EK-oxidation process].

    Science.gov (United States)

    Fan, Guang-Ping; Cang, Long; Zhou, Dong-Mei; Zhou, Li-Xiang

    2011-11-01

    The effect of different soil types (red soil,yellow-brown soil and black soil) on the electrokinetic (EK)-oxidation remediation of heavy metals-organic pollutant contaminated soil was studied in laboratory-scale experiments. Copper and pyrene were chosen as model pollutant, and 12% H2O2, 10% hydroxypropyl-beta-cyclodextrin and 0.01 mol x L(-1) NaNO3 solution were added into the anode and cathode cell. The applied voltage was 1 V x cm(-1). After 15 days of EK remediation, the removal rate of pyrene and copper in red soil, yellow-brown soil and black soil were 38.5%, 46.8%, 51.3% for pyrene and 85.0%, 22.6%, 24.1% for Cu, respectively. The high pH of black soil produced high electroosmotic flow and increased the exposure of oxidants and pollutants, meanwhile the low clay content was also conducive to the desorption of pyrene. The low pH and organic matter of red soil affected the chemical species distribution of Cu and increased its removal rate. It is concluded that soil pH, clay content and heavy metal speciation in soil are the dominant factors affecting the migration and removal efficiency of pollutants.

  1. The use of chelating agents in the remediation of metal-contaminated soils: A review

    Energy Technology Data Exchange (ETDEWEB)

    Lestan, Domen [Agronomy Department, Centre for Soil and Environmental Science, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana (Slovenia); Luo Chunling [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Li Xiangdong [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)], E-mail: cexdli@polyu.edu.hk

    2008-05-15

    This paper reviews current remediation technologies that use chelating agents for the mobilization and removal of potentially toxic metals from contaminated soils. These processes can be done in situ as enhanced phytoextraction, chelant enhanced electrokinetic extraction and soil flushing, or ex situ as the extraction of soil slurry and soil heap/column leaching. Current proposals on how to treat and recycle waste washing solutions after soil is washed are discussed. The major controlling factors in phytoextraction and possible strategies for reducing the leaching of metals associated with the application of chelants are also reviewed. Finally, the possible impact of abiotic and biotic soil factors on the toxicity of metals left after the washing of soil and enhanced phytoextraction are briefly addressed. - The use of synthetic chelants for soil washing and enhanced phytoextraction by plants has been well studied for the remediation of metal-contaminated soils in the last two decades.

  2. The use of chelating agents in the remediation of metal-contaminated soils: A review

    International Nuclear Information System (INIS)

    Lestan, Domen; Luo Chunling; Li Xiangdong

    2008-01-01

    This paper reviews current remediation technologies that use chelating agents for the mobilization and removal of potentially toxic metals from contaminated soils. These processes can be done in situ as enhanced phytoextraction, chelant enhanced electrokinetic extraction and soil flushing, or ex situ as the extraction of soil slurry and soil heap/column leaching. Current proposals on how to treat and recycle waste washing solutions after soil is washed are discussed. The major controlling factors in phytoextraction and possible strategies for reducing the leaching of metals associated with the application of chelants are also reviewed. Finally, the possible impact of abiotic and biotic soil factors on the toxicity of metals left after the washing of soil and enhanced phytoextraction are briefly addressed. - The use of synthetic chelants for soil washing and enhanced phytoextraction by plants has been well studied for the remediation of metal-contaminated soils in the last two decades

  3. Soil and groundwater remediation guidelines for methanol

    International Nuclear Information System (INIS)

    2010-12-01

    Methanol is used by oil and gas operators to inhibit hydrate formation in the recovery of heavy oils, in natural gas production and transport, as well as in various other production applications. Emissions from methanol primary occur from miscellaneous solvent usage, methanol production, end-product manufacturing, and storage and handling losses. This document provided soil and groundwater remediation guidelines for methanol releases into the environment. The guidelines were consistent with the Alberta Environment tier 1 soil and groundwater framework. The chemical and physical properties of methanol were reviewed. The environmental fate and behavior of methanol releases was discussed, and the behaviour and effects of methanol in terrestrial and aquatic biota were evaluated. The toxicity of methanol and its effects in humans and mammalian species were reviewed. Soil quality and ground water quality guidelines were presented. Surface water and soil guideline calculation methods were provided, and ecological exposure and ground water pathways were discussed. Management limits for methanol concentrations were also provided. 162 refs., 18 tabs., 4 figs.

  4. Electrodialytic soil remediation enhanced by low frequency pulse current

    DEFF Research Database (Denmark)

    Sun, Tian R.; Ottosen, Lisbeth M.; Mortensen, John

    2013-01-01

    The effect of low frequency pulse current on decreasing the polarization and energy consumption during the process of electrodialytic soil remediation was investigated in the present work. The results indicated that the transportation of cations through the cation exchange membrane was the rate...

  5. Immediate remediation of heavy metal (Cr(VI)) contaminated soil by high energy electron beam irradiation

    International Nuclear Information System (INIS)

    Zhang, Jing; Zhang, Guilong; Cai, Dongqing; Wu, Zhengyan

    2015-01-01

    Highlights: • An immediate remediation method for Cr(VI) contaminated soil (CCS) was developed. • High energy electron beam (HEEB) irradiation could reduce Cr(VI) in CCS to Cr(III). • This effect was attributed to electrons, hydrated electrons, and reductive radicals. • This remediation method was effective, environmentally friendly, and low-cost. - Abstract: This work developed an immediate and high-performance remediation method for Cr(VI) contaminated soil (CCS) using high energy electron beam (HEEB) irradiation. The result indicated that, compared with γ-ray irradiation, HEEB irradiation displayed a significant reduction efficiency on Cr(VI) in CCS to Cr(III) with substantially lower toxicity, which was mainly attributed to the reduction effects of electrons, hydrated electrons, and reductive radicals generated in the irradiation process of HEEB. This work could provide a one-step and effective method for the remediation of heavy metal contaminated soil (HMCS)

  6. Immediate remediation of heavy metal (Cr(VI)) contaminated soil by high energy electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jing; Zhang, Guilong [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Cai, Dongqing, E-mail: dqcai@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Wu, Zhengyan, E-mail: zywu@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China)

    2015-03-21

    Highlights: • An immediate remediation method for Cr(VI) contaminated soil (CCS) was developed. • High energy electron beam (HEEB) irradiation could reduce Cr(VI) in CCS to Cr(III). • This effect was attributed to electrons, hydrated electrons, and reductive radicals. • This remediation method was effective, environmentally friendly, and low-cost. - Abstract: This work developed an immediate and high-performance remediation method for Cr(VI) contaminated soil (CCS) using high energy electron beam (HEEB) irradiation. The result indicated that, compared with γ-ray irradiation, HEEB irradiation displayed a significant reduction efficiency on Cr(VI) in CCS to Cr(III) with substantially lower toxicity, which was mainly attributed to the reduction effects of electrons, hydrated electrons, and reductive radicals generated in the irradiation process of HEEB. This work could provide a one-step and effective method for the remediation of heavy metal contaminated soil (HMCS)

  7. The Impact of Thermal Remediation on Soil Rehabilitation

    Science.gov (United States)

    Pape, Andrew; Switzer, Christine; Knapp, Charles

    2013-04-01

    In an effort to restore the social and economic value of brownfield sites contaminated by hazardous organic liquids, many new remediation techniques involving the use of elevated temperatures to desorb and extract or destroy these contaminants have been developed. These approaches are typically applied to heavily contaminated soils to effect substantial source removal from the subsurface. These processes operate over a range of temperatures from just above ambient to in excess of 1000˚C depending on technology choice and contaminant type. To facilitate the successful rehabilitation of treated soils for agriculture, biomass production, or habitat enrichment the effects of high temperatures on the ability of soil to support biological activity needs to be understood. Four soils were treated with high temperatures or artificially contaminated and subjected to a smouldering treatment (600-1100°C) in this investigation. Subsequent chemical analysis, plant growth trials and microbial analysis were used to characterise the impacts of these processes on soil geochemistry, plant health, and potential for recovery. Decreases were found in levels of carbon (>250˚C), nitrogen (>500˚C) and phosphorus (1000˚C) with intermediate temperatures having variable affects on bio-available levels. Macro and micro nutrients such as potassium, calcium, zinc and copper also showed changes with general trends towards reduced bioavailability at higher temperatures. Above 500°C, cation exchange capacity and phosphate adsorption were lowered indicating that nutrient retention will be a problem in some treated soils. In addition, these temperatures reduced the content of clay sized particles changing the texture of the soils. These changes had a statistically significant impact on plant growth with moderate growth reductions occurring at 250°C and 500°C. Above 750°C, growth was extremely limited and soils treated at these temperatures would need major restorative efforts. Microbial re

  8. Remediation of Soil Contaminated with Uranium using a Biological Method

    International Nuclear Information System (INIS)

    Park, Hye Min; Kim, Gye Nam; Shon, Dong Bin; Lee, Ki Won; Chung, Un Soo; Moon, Jai Kwon

    2011-01-01

    Bioremediation is a method to cleanup contaminants in soil or ground water with microorganisms. The biological method can reduce the volume of waste solution and the construction cost and operation cost of soil remediation equipment. Bioremediation can be divided into natural attenuation, bioaugmentation, biostimulation. Biostimulation is technology to improve natural purification by adding nutritional substances, supplying oxygen and controlling pH. In this study, penatron, that is a nutritional substances, was mixed with soil. Optimum conditions for mixing ratios of penatron and soil, and the pH of soil was determined through several bioremediation experiments with soil contaminated with uranium. Also, under optimum experiment conditions, the removal efficiencies of soil and concrete according to reaction time were measured for feasibility analysis of soil and concrete bioremediations

  9. The use of microbial gene abundance in the development of fuel remediation guidelines in polar soils.

    Science.gov (United States)

    Richardson, Elizabeth L; King, Catherine K; Powell, Shane M

    2015-04-01

    Terrestrial fuel spills in Antarctica commonly occur on ice-free land around research stations as the result of human activities. Successful spill clean-ups require appropriate targets that confirm contaminated sites are no longer likely to pose environmental risk following remediation. These targets are based on knowledge of the impacts of contaminants on the soil ecosystem and on the response of native biota to contamination. Our work examined the response of soil microbial communities to fuel contamination by measuring the abundance of genes involved in critical soil processes, and assessed the use of this approach as an indicator of soil health in the presence of weathered and fresh fuels. Uncontaminated and contaminated soils were collected from the site of remediation treatment of an aged diesel spill at Casey Station, East Antarctica in December 2012. Uncontaminated soil was spiked with fresh Special Antarctic Blend (SAB) diesel to determine the response of the genes to fresh fuel. Partly remediated soil containing weathered SAB diesel was diluted with uncontaminated soil to simulate a range of concentrations of weathered fuel and used to determine the response of the genes to aged fuel. Quantitative PCR (qPCR) was used to measure the abundance of rpoB, alkB, cat23, and nosZ in soils containing SAB diesel. Differences were observed between the abundance of genes in control soils versus soils containing weathered and fresh fuels. Typical dose-response curves were generated for genes in response to the presence of fresh fuel. In contrast, the response of these genes to the range of weathered fuel appeared to be due to dilution, rather than to the effect of the fuel on the microbial community. Changes in microbial genes in response to fresh contamination have potential as a sensitive measure of soil health and for assessments of the effect of fuel spills in polar soils. This will contribute to the development of remediation guidelines to assist in management

  10. Remediation of soil contaminated with pesticides by treatment with gamma radiation

    International Nuclear Information System (INIS)

    Santos, Janilson Silva

    2009-01-01

    The discharge of empty plastic packaging of pesticides can be an environmental concern mainly by soil contamination. Nowadays, Brazil figures in third place among the leading world pesticide markets. An understanding of the processes that affect the transport and fate of pesticides is crucial to assess their potential for contamination of soil and groundwater, and to develop efficient and cost-effective site management and soil remediation strategies. Due to its impact on soil remediation has made sorption a major topic of research on soil-pesticide interactions. The main objective of this study is the evaluation of the pesticides transferring from contaminated mixture of commercial polymeric packing of high-density polyethylene, HDPE, used in agriculture to soil and their removal by gamma irradiation. Two soil samples of argyles compositions and media composition were exposed to a mixture of commercial polymeric packing contaminated with the pesticides methomyl, dimethoate, carbofuran, methidathion, triazine, thiophos, atrazine, ametryne, endosulfan, chloropyrifos, thriazophos and trifluralin. The pesticides leaching from packaging to soil was homogeneous considering a experimental research. The radiation treatment presented high efficiency on removal pesticides from both soil, but it depends on the physical-chemical characteristics of the contaminated soil. The higher efficiency was obtained in soils with higher organic material and humidity. The higher efficiency was obtained for the medium texture soil, with 20 kGy all present pesticides were removed in all layers. In the case of argyles texture soil, it was necessary a 30 kGy to remove the totality of present pesticides. (author)

  11. Seasonal and temporal evolution of nutrient composition of pastures grown on remediated and non remediated soils affected by trace element contamination (Guadiamar Valley, SW Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Madejon, P.; Dominguez, M. T.; Murillo, J. M.

    2010-07-01

    Elevated trace element concentrations in soils can affect the solubility and uptake of essential elements, resulting in nutrient deficiencies in plant tissues. The present paper deals with nutrient composition of pastures established on polluted and remediated soils (Green Corridor of the Guadiamar river Valley), in order to check the potential nutritional disorders that could derive from the soil pollution. In addition, nutrient composition of a representative grass, Cynodon dactylon, collected in 1999 and 2008 was compared in remediated and non-remediated sites of the polluted area. In general, nutrient concentrations of pastures were similar or even higher in polluted sites compared to control sites. Therefore, the estimated potential ingestion of main nutrients by horses (the most abundant animals in the area) was also greater in the polluted and remediated soils and covered their nutritional requirements (more than 300 (N), 70 (S), 35 (P), 400 (K), 175 (Ca) and 30 (Mg) mg kg{sup -}1 body weight day {sup -}1 in spring and autumn). Temporal evolution of nutrients and physiological ratios (N/S, Ca/P, K/Na, K/Ca+Mg) in C. dactylon showed a significant variation from 1999 to 2008, especially in the non-remediated area, leading to a recovery of the nutritional quality of this grass. The reasonable nutritional quality of pastures and the absence of negative interactions between nutrients and trace elements seem to indicate a stabilisation of soil pollutants in the affected area. (Author) 41 refs.

  12. Impact of carbonate on the efficiency of heavy metal removal from kaolinite soil by the electrokinetic soil remediation method

    Energy Technology Data Exchange (ETDEWEB)

    Ouhadi, V.R., E-mail: vahidouhadi@yahoo.ca [Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Yong, R.N. [RNY Geoenvironmental Research, North Saanich (Canada); Shariatmadari, N. [Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Saeidijam, S.; Goodarzi, A.R.; Safari-Zanjani, M. [Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of)

    2010-01-15

    While the feasibility of using electrokinetics to decontaminate soils has been studied by several authors, the effects of soil composition on the efficiency of this method of decontamination has yet to be fully studied. This study focuses its attention on the effect of 'calcite or carbonate' (CaCO{sub 3}) on removal efficiency in electrokinetic soil remediation. Bench scale experiments were conducted on two soils: kaolinite and natural-soil of a landfill in Hamedan, Iran. Prescribed quantities of carbonates were mixed with these soils which were subsequently contaminated with zinc nitrate. After that, electrokinetic experiments were conducted to determine the efficiency of electrokinetic remediation. The results showed that an increase in the quantity of carbonate caused a noticeable increase on the contaminant retention of soil and on the resistance of soil to the contaminant removal by electrokinetic method. Because the presence of carbonates in the soil increases its buffering capacity, acidification is reduced, resulting in a decrease in the rate of heavy metal removed from the contaminant soil. This conclusion was validated by the evaluation of efficiency of electrokinetic method on a soil sample from the liner of a waste disposal site, with 28% carbonates.

  13. Impact of carbonate on the efficiency of heavy metal removal from kaolinite soil by the electrokinetic soil remediation method

    International Nuclear Information System (INIS)

    Ouhadi, V.R.; Yong, R.N.; Shariatmadari, N.; Saeidijam, S.; Goodarzi, A.R.; Safari-Zanjani, M.

    2010-01-01

    While the feasibility of using electrokinetics to decontaminate soils has been studied by several authors, the effects of soil composition on the efficiency of this method of decontamination has yet to be fully studied. This study focuses its attention on the effect of 'calcite or carbonate' (CaCO 3 ) on removal efficiency in electrokinetic soil remediation. Bench scale experiments were conducted on two soils: kaolinite and natural-soil of a landfill in Hamedan, Iran. Prescribed quantities of carbonates were mixed with these soils which were subsequently contaminated with zinc nitrate. After that, electrokinetic experiments were conducted to determine the efficiency of electrokinetic remediation. The results showed that an increase in the quantity of carbonate caused a noticeable increase on the contaminant retention of soil and on the resistance of soil to the contaminant removal by electrokinetic method. Because the presence of carbonates in the soil increases its buffering capacity, acidification is reduced, resulting in a decrease in the rate of heavy metal removed from the contaminant soil. This conclusion was validated by the evaluation of efficiency of electrokinetic method on a soil sample from the liner of a waste disposal site, with 28% carbonates.

  14. Remediation of Nitrobenzene Contaminated Soil by Combining Surfactant Enhanced Soil Washing and Effluent Oxidation with Persulfate

    Science.gov (United States)

    Yan, Jingchun; Gao, Weiguo; Qian, Linbo; Han, Lu; Chen, Yun; Chen, Mengfang

    2015-01-01

    The combination of surfactant enhanced soil washing and degradation of nitrobenzene (NB) in effluent with persulfate was investigated to remediate NB contaminated soil. Aqueous solution of sodium dodecylbenzenesulfonate (SDBS, 24.0 mmol L-1) was used at a given mass ratio of solution to soil (20:1) to extract NB contaminated soil (47.3 mg kg-1), resulting in NB desorption removal efficient of 76.8%. The washing effluent was treated in Fe2+/persulfate and Fe2+/H2O2 systems successively. The degradation removal of NB was 97.9%, being much higher than that of SDBS (51.6%) with addition of 40.0 mmol L-1 Fe2+ and 40.0 mmol L-1 persulfate after 15 min reaction. The preferential degradation was related to the lone pair electron of generated SO4•−, which preferably removes electrons from aromatic parts of NB over long alkyl chains of SDBS through hydrogen abstraction reactions. No preferential degradation was observed in •OH based oxidation because of its hydrogen abstraction or addition mechanism. The sustained SDBS could be reused for washing the contaminated soil. The combination of the effective surfactant-enhanced washing and the preferential degradation of NB with Fe2+/persulfate provide a useful option to remediate NB contaminated soil. PMID:26266532

  15. Innovative vitrification for soil remediation

    International Nuclear Information System (INIS)

    Jetta, N.W.; Patten, J.S.; Hart, J.G.

    1995-01-01

    The objective of this DOE demonstration program is to validate the performance and operation of the Vortec Cyclone Melting System (CMS trademark) for the processing of LLW contaminated soils found at DOE sites. This DOE vitrification demonstration project has successfully progressed through the first two phases. Phase 1 consisted of pilot scale testing with surrogate wastes and the conceptual design of a process plant operating at a generic DOE site. The objective of Phase 2, which is scheduled to be completed the end of FY 95, is to develop a definitive process plant design for the treatment of wastes at a specific DOE facility. During Phase 2, a site specific design was developed for the processing of LLW soils and muds containing TSCA organics and RCRA metal contaminants. Phase 3 will consist of a full scale demonstration at the DOE gaseous diffusion plant located in Paducah, KY. Several DOE sites were evaluated for potential application of the technology. Paducah was selected for the demonstration program because of their urgent waste remediation needs as well as their strong management and cost sharing financial support for the project. During Phase 2, the basic nitrification process design was modified to meet the specific needs of the new waste streams available at Paducah. The system design developed for Paducah has significantly enhanced the processing capabilities of the Vortec vitrification process. The overall system design now includes the capability to shred entire drums and drum packs containing mud, concrete, plastics and PCB's as well as bulk waste materials. This enhanced processing capability will substantially expand the total DOE waste remediation applications of the technology

  16. Assessment of the Use of Natural Materials for the Remediation of Cadmium Soil Contamination.

    Science.gov (United States)

    de O Pinto, Tatiana; García, Andrés C; Guedes, Jair do N; do A Sobrinho, Nelson M B; Tavares, Orlando C H; Berbara, Ricardo L L

    2016-01-01

    Rice plants accumulate cadmium (Cd2+) within the grain, increasing the danger of human exposure. Natural materials have been used in soil remediation, but few studies have examined the risks (based on the bioavailability of these metals to plants) of using these materials, so the practice remains controversial. In the present study, we evaluated the effectiveness of biochar produced from sugarcane bagasse, vermicompost (VC), vermicompost solid residue (VCR) and humin for remediation of Cd2+-contaminated soils. We characterized the interactions between these materials and Cd2+ and evaluated their capacity to alter Cd2+ availability to rice plants. Our results show that under the conditions in this study, biochar and humin were not effective for soil remediation. Although biochar had high Cd2+ retention, it was associated with high Cd2+ bioavailability and increased Cd2+ accumulation in rice plants. VC and VCR had high Cd2+ retention capacity as well as low Cd2+ availability to plants. These characteristics were especially notable for VCR, which was most effective for soil remediation. The results of our study demonstrate that in the tested materials, the bioavailability of Cd2+ to plants is related to their structural characteristics, which in turn determine their retention of Cd2+.

  17. Assessment of the Use of Natural Materials for the Remediation of Cadmium Soil Contamination.

    Directory of Open Access Journals (Sweden)

    Tatiana de O Pinto

    Full Text Available Rice plants accumulate cadmium (Cd2+ within the grain, increasing the danger of human exposure. Natural materials have been used in soil remediation, but few studies have examined the risks (based on the bioavailability of these metals to plants of using these materials, so the practice remains controversial. In the present study, we evaluated the effectiveness of biochar produced from sugarcane bagasse, vermicompost (VC, vermicompost solid residue (VCR and humin for remediation of Cd2+-contaminated soils. We characterized the interactions between these materials and Cd2+ and evaluated their capacity to alter Cd2+ availability to rice plants. Our results show that under the conditions in this study, biochar and humin were not effective for soil remediation. Although biochar had high Cd2+ retention, it was associated with high Cd2+ bioavailability and increased Cd2+ accumulation in rice plants. VC and VCR had high Cd2+ retention capacity as well as low Cd2+ availability to plants. These characteristics were especially notable for VCR, which was most effective for soil remediation. The results of our study demonstrate that in the tested materials, the bioavailability of Cd2+ to plants is related to their structural characteristics, which in turn determine their retention of Cd2+.

  18. In-Situ Electrokinetic Remediation for Metal Contaminated Soils

    Science.gov (United States)

    2001-03-01

    phytoremediation , and electrokinetic extraction. The US Army Environmental Center (USAEC) and Engineer Research and Development Center (ERDC...California (CA) List Metals: Antimony, arsenic, barium, beryllium, cadmium, chromium, cobalt, copper, lead, mercury , molybdenum, nickel, selenium...Comparison Technologies with which electrokinetic remediation must compete are "Dig and Haul", Soil Washing, and Phytoremediation . "Dig and haul

  19. Effect of long-term electrodialytic soil remediation on Pb removal and soil weathering

    DEFF Research Database (Denmark)

    Skibsted, Gry; Ottosen, Lisbeth M.; Elektorowicz, Maria

    2017-01-01

    Weathering of soil minerals during long-term electrochemical soil remediation was evaluated for two different soils: an industrially Pb contaminated soil with high carbonate content and an unpolluted soil with low carbonate content. A constant current of 5 mA was applied for 842 days, and sampling...... was made 22 times during the treatment. The overall qualitative mineral composition was unaffected by electrodialysis, except for calcite removal which was complete. However, dissolution and removal of Al, Fe, Si, Mg, Ca and Pb from the soil during the treatment exceeded the fraction extractable by...... digestion in 7 M HNO3, and provided evidence of enhanced mineral dissolution induced by the current. Nevertheless, the total dissolved Si and Al only constituted 0.2-0.3 % and 1.1-3.5 % of the total content, while the Pb overall removal from the contaminated soil was only 8.1 %. An observed reduction in the...

  20. Remediation of hydrocarbon-contaminated soils by ex situ microwave treatment: technical, energy and economic considerations.

    Science.gov (United States)

    Falciglia, P P; Vagliasindi, F G A

    2014-01-01

    In this study, the remediation of diesel-polluted soils was investigated by simulating an ex situ microwave (MW) heating treatment under different conditions, including soil moisture, operating power and heating duration. Based on experimental data, a technical, energy and economic assessment for the optimization of full-scale remediation activities was carried out. Main results show that the operating power applied significantly influences the contaminant removal kinetics and the moisture content in soil has a major effect on the final temperature reachable during MW heating. The first-order kinetic model showed an excellent correlation (r2 > 0.976) with the experimental data for residual concentration at all operating powers and for all soil moistures tested. Excellent contaminant removal values up to 94.8% were observed for wet soils at power higher than 600 W for heating duration longer than 30 min. The use of MW heating with respect to a conventional ex situ thermal desorption treatment could significantly decrease the energy consumption needed for the removal of hydrocarbon contaminants from soils. Therefore, the MW treatment could represent a suitable cost-effective alternative to the conventional thermal treatment for the remediation of hydrocarbon-polluted soil.

  1. Remediation of diesel-oil-contaminated soil using peat

    International Nuclear Information System (INIS)

    Ghaly, R.A.; Pyke, J.B.; Ghaly, A.E.; Ugursal, V.I.

    1999-01-01

    We investigated a remediation process for diesel-contaminated soil, in which water was used to remove the diesel from the soil and peat was used to absorb the diesel layer formed on the surface of the water. The percolation of water through the soil was uniform. The time required for water to percolate the soil and for the layers (soil, water, and diesel) to separate depended on the soil depth. Both the depth of soil and mixing affected the thickness of the diesel layer and thus diesel recovery from the contaminated soil. Higher diesel recovery was achieved with smaller soil depth and mixing. The initial moisture content and the lower heating value of the peat were 7.1% and 17.65 MJ/kg, respectively. The final moisture content and lower heating value of the diesel-contaminated peat obtained from the experiment with mixing were 8.65 - 10.80% and 32.57 - 35.81 MJ/kg, respectively. The energy content of the diesel-contaminated peat is much higher than that of coal, and the moisture content is within the range recommended for biomass gasification. (author)

  2. Effect of soil organic matter on antimony bioavailability after the remediation process.

    Science.gov (United States)

    Nakamaru, Yasuo Mitsui; Martín Peinado, Francisco José

    2017-09-01

    We evaluated the long-term (18 year) and short-term (4 weeks) changes of Sb in contaminated soil with SOM increase under remediation process. In the Aznalcóllar mine accident (1998) contaminated area, the remediation measurement implemented the Guadiamar Green Corridor, where residual pollution is still detected. Soils of the re-vegetated area (O2) with high pH and high SOM content, moderately re-vegetated area (O1) and unvegetated area (C) were sampled. Soil pH, CEC, SOM amount and soil Sb forms were evaluated. Soil Sb was measured as total, soluble, exchangeable, EDTA extractable, acid oxalate extractable, and pyro-phosphate extractable fractions. Further, the short-term effect of artificial organic matter addition was also evaluated with incubation study by adding compost to the sampled soil from C, O1 and O2 areas. After 4 weeks of incubation, soil chemical properties and Sb forms were evaluated. In re-vegetated area (O2), soil total Sb was two times lower than in unvegetated area (C); however, soluble, exchangeable, and EDTA extractable Sb were 2-8 times higher. The mobile/bioavailable Sb increase was also observed after 4 weeks of incubation with the addition of compost. Soluble, exchangeable, and EDTA extractable Sb was increased 2-4 times by compost addition. By the linear regression analysis, the significantly related factors for soluble, exchangeable, and EDTA extractable Sb values were pH, CEC, and SOM, respectively. Soluble Sb increase was mainly related to pH rise. Exchangeable Sb should be bound by SOM-metal complex and increased with CEC. EDTA extractable fraction should be increased with increase of SOM as SOM-Fe associated Sb complex. From these results, it was shown that increase of SOM under natural conditions or application of organic amendment under remediation process should increase availability of Sb to plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Surfactant flushing remediation of o-dichlorobenzene and p-dichlorobenzene contaminated soil.

    Science.gov (United States)

    Pei, Guangpeng; Zhu, Yuen; Cai, Xiatong; Shi, Weiyu; Li, Hua

    2017-10-01

    Surfactant-enhanced remediation is used to treat dichlorobenzene (DCB) contaminated soil. In this study, soil column experiments were conducted to investigate the removal efficiencies of o-dichlorobenzene (o-DCB) and p-dichlorobenzene (p-DCB) from contaminated soil using micellar solutions of biosurfactants (saponin, alkyl polyglycoside) compare to a chemically synthetic surfactant (Tween 80). Leachate was collected and analyzed for o-DCB and p-DCB content. In addition, soil was analyzed to explore the effect of surfactants on soil enzyme activities. Results showed that the removal efficiency of o-DCB and p-DCB was highest for saponin followed by alkyl polyglycoside and Tween 80. The maximum o-DCB and p-DCB removal efficiencies of 76.34% and 80.43%, respectively, were achieved with 4 g L -1 saponin solution. However, an opposite result was observed in the cumulative mass of o-DCB and p-DCB in leachate. The cumulative extent of o-DCB and p-DCB removal by the biosurfactants saponin and alkyl polyglycoside was lower than that of the chemically synthetic surfactant Tween 80 in leachate. Soil was also analyzed to explore the effect of surfactants on soil enzyme activities. The results indicated that surfactants were potentially effective in facilitating soil enzyme activities. Thus, it was confirmed that the biosurfactants saponin and alkyl polyglycoside could be used for remediation of o-DCB and p-DCB contaminated soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. 75 FR 7591 - Guidance on Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and...

    Science.gov (United States)

    2010-02-22

    ... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-SFUND-2009-0907; FRL-9114-6] RIN 2050-ZA05 Guidance on Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites; Extension of... Interim Preliminary Remediation Goals for Dioxin in Soil at Comprehensive Environmental Response...

  5. Soil remediation using a coupled process: soil washing with surfactant followed by photo-Fenton oxidation

    International Nuclear Information System (INIS)

    Villa, Ricardo D.; Trovo, Alam G.; Nogueira, Raquel F. Pupo

    2010-01-01

    In the present work the use of a coupled process, soil washing and photo-Fenton oxidation, was investigated for remediation of a soil contaminated with p,p'-DDT (DDT) and p,p'-DDE (DDE), and a soil artificially contaminated with diesel. In the soil washing experiments, Triton X-100 (TX-100) aqueous solutions were used at different concentrations to obtain wastewaters with different compositions. Removal efficiencies of 66% (DDT), 80% (DDE) and 100% (diesel) were achieved for three sequential washings using a TX-100 solution strength equivalent to 12 times the effective critical micelle concentration of the surfactant (12 CMC eff ). The wastewater obtained was then treated using a solar photo-Fenton process. After 6 h irradiation, 99, 95 and 100% degradation efficiencies were achieved for DDT, DDE and diesel, respectively. In all experiments, the concentration of dissolved organic carbon decreased by at least 95%, indicating that residual concentration of contaminants and/or TX-100 in the wastewater was very low. The co-extraction of metals was also evaluated. Among the metals analyzed (Pb, Cr, Ni, Cu, Cd, Mn and Co), only Cr and Mn were detected in the wastewater at concentrations above the maximum value permitted by current Brazilian legislation. The effective removal of contaminants from soil by the TX-100 washing process, together with the high degradation efficiency of the solar photo-Fenton process, suggests that this procedure could be a useful option for soil remediation.

  6. Soil remediation using a coupled process: soil washing with surfactant followed by photo-Fenton oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Villa, Ricardo D., E-mail: ricardovilla@ufmt.br [UNESP - Sao Paulo State University, Institute of Chemistry of Araraquara, Department of Analytical Chemistry, P.O. Box 355, 14801-970 Araraquara, SP (Brazil); Trovo, Alam G., E-mail: alamtrovo@smail.ufsm.br [UNESP - Sao Paulo State University, Institute of Chemistry of Araraquara, Department of Analytical Chemistry, P.O. Box 355, 14801-970 Araraquara, SP (Brazil); Nogueira, Raquel F. Pupo, E-mail: nogueira@iq.unesp.br [UNESP - Sao Paulo State University, Institute of Chemistry of Araraquara, Department of Analytical Chemistry, P.O. Box 355, 14801-970 Araraquara, SP (Brazil)

    2010-02-15

    In the present work the use of a coupled process, soil washing and photo-Fenton oxidation, was investigated for remediation of a soil contaminated with p,p'-DDT (DDT) and p,p'-DDE (DDE), and a soil artificially contaminated with diesel. In the soil washing experiments, Triton X-100 (TX-100) aqueous solutions were used at different concentrations to obtain wastewaters with different compositions. Removal efficiencies of 66% (DDT), 80% (DDE) and 100% (diesel) were achieved for three sequential washings using a TX-100 solution strength equivalent to 12 times the effective critical micelle concentration of the surfactant (12 CMC{sub eff}). The wastewater obtained was then treated using a solar photo-Fenton process. After 6 h irradiation, 99, 95 and 100% degradation efficiencies were achieved for DDT, DDE and diesel, respectively. In all experiments, the concentration of dissolved organic carbon decreased by at least 95%, indicating that residual concentration of contaminants and/or TX-100 in the wastewater was very low. The co-extraction of metals was also evaluated. Among the metals analyzed (Pb, Cr, Ni, Cu, Cd, Mn and Co), only Cr and Mn were detected in the wastewater at concentrations above the maximum value permitted by current Brazilian legislation. The effective removal of contaminants from soil by the TX-100 washing process, together with the high degradation efficiency of the solar photo-Fenton process, suggests that this procedure could be a useful option for soil remediation.

  7. Recare - Preventing and remediating degradation of soils in Europe through land care

    NARCIS (Netherlands)

    Lynden, van G.; Ritsema, C.J.; Hessel, R.

    2014-01-01

    Much knowledge is available on soil threats in Europe, but this is fragmented and incomplete, in particular regarding the complexity and functioning of soil systems and their interaction with human activities. The main aim of the new RECARE project is to develop effective prevention, remediation and

  8. Remediation of metal polluted mine soil with compost: Co-composting versus incorporation

    International Nuclear Information System (INIS)

    Tandy, Susan; Healey, John R.; Nason, Mark A.; Williamson, Julie C.; Jones, Davey L.

    2009-01-01

    Trace element contamination of post-industrial sites represents a major environmental problem and sustainable management options for remediating them are required. This study compared two strategies for immobilizing trace elements (Cu, Pb, Zn, and As) in mine spoil: (1) co-composting contaminated soil with organic wastes and (2) conventional incorporation of mature compost into contaminated soil. Sequential chemical extraction of the soil was performed to determine temporal changes in trace element fractionation and bioavailability during composting and plant growth. We show that mine spoil can be co-composted successfully and this action causes significant shifts in metal availability. However, co-composting did not lead to significant differences in metal partitioning in soil or in plant metal uptake compared with simply mixing mine spoil with mature compost. Both treatments promoted plant growth and reduced metal accumulation in plants. We conclude that co-composting provides little additional benefit for remediating trace-element-polluted soil compared with incorporation of compost. - Co-composting did not provide enhanced stabilization of trace elements over the conventional addition of compost to contaminated land

  9. Remediation of Arsenic contaminated soil using malposed intercropping of Pteris vittata L. and maize.

    Science.gov (United States)

    Ma, Jie; Lei, En; Lei, Mei; Liu, Yanhong; Chen, Tongbin

    2018-03-01

    Intercropping of arsenic (As) hyperaccumulator and cash crops during remediation of contaminated soil has been applied in farmland remediation project. However, little is known about the fate of As fractions in the soil profile and As uptake within the intercropping plants under field condition. In this study, As removal, uptake, and translocation were investigated within an intercropping system of Pteris vittata L. (P. vittata) and maize (Zea mays). Results indicated that the concentration of As associated with amorphous Fe (hydr)oxides in the 10-20 cm soil layer was significantly lower under malposed intercropping of P. vittata and maize, and As accumulation in P. vittata and biomass of P. vittata were simultaneously higher under malposed intercropping than under coordinate intercropping, leading to a 2.4 times higher rate of As removal. Although maize roots absorbed over 13.4 mg kg -1 As and maize leaves and flowers accumulated over 21.5 mg kg -1 As (translocation factor higher than 1), grains produced in all intercropping modes accumulated lower levels of As, satisfying the standard for human consumption. Our results suggested that malposed intercropping of a hyperaccumulator and a low-accumulation cash crop was an ideal planting pattern for As remediation in soil. Furthermore, timely harvest of P. vittata, agronomic strategies during remediation, and appropriate management of the above ground parts of P. vittata and high-As tissues of cash crops may further improve remediation efficiency. Copyright © 2017. Published by Elsevier Ltd.

  10. EDTA and HCl leaching of calcareous and acidic soils polluted with potentially toxic metals: remediation efficiency and soil impact.

    Science.gov (United States)

    Udovic, Metka; Lestan, Domen

    2012-07-01

    The environmental risk of potentially toxic metals (PTMs) in soil can be diminished by their removal. Among the available remediation techniques, soil leaching with various solutions is one of the most effective but data about the impact on soil chemical and biological properties are still scarce. We studied the effect of two common leaching agents, hydrochloric acid (HCl) and a chelating agent (EDTA) on Pb, Zn, Cd removal and accessibility and on physico-chemical and biological properties in one calcareous, pH neutral soil and one non-calcareous acidic soil. EDTA was a more efficient leachant compared to HCl: up to 133-times lower chelant concentration was needed for the same percentage (35%) of Pb removal. EDTA and HCl concentrations with similar PTM removal efficiency decreased PTM accessibility in both soils but had different impacts on soil properties. As expected, HCl significantly dissolved carbonates from calcareous soil, while EDTA leaching increased the pH of the acidic soil. Enzyme activity assays showed that leaching with HCl had a distinctly negative impact on soil microbial and enzyme activity, while leaching with EDTA had less impact. Our results emphasize the importance of considering the ecological impact of remediation processes on soil in addition to the capacity for PTM removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Remediation of lead contaminated soil

    International Nuclear Information System (INIS)

    Urban, W.; Krishnamurthy, S.

    1992-01-01

    Lead contaminated soil in urban area is of major concern because of the potential health risk to children. Many studies have established a direct correlation between lead in soil and elevated blood lead levels in children. In Minneapolis, Minnesota, Mielke et al. (1983) reported that 50% of the Hmong children with lead poisioning were in areas where soil lead levels were between 500 and 1000 micrograms per gram (ug/g), and 40% of the children suffering from lead poisioning lived in areas where soil lead levels exceeded 1000 ug/g. In urban areas, lead pollution in soil has come from many different sources. The sources include lead paint, lead batteries and automobile exhaust. Olson and Skogerbee (1975) found the following lead compounds in soils where the primary source of pollution was from automobiles: lead sulfate, lead oxide, lead dioxide, lead sulfide, and metallic lead. The primary form of lead found was lead sulfate. Lead sulfate, lead tetraoxide, white lead, and other forms of lead have been used in the manufacture of paints for houses. At present, two remediation techniques, solidification and Bureau of Mines fluosilicic acid leaching, are available for lead-contaminated sites. The objective of the present investigation at the Risk Reduction Engineering Laboratory (RREL), Edison, was to try to solubilize the lead species by appropriate reagents and then recover the contaminants by precipitation as lead sulfate, using environmentally acceptable methods. The apparatus used for mixing was a LabMaster mixer, with variable speed and high-shear impeller. Previous work had used nitric acid for dissolving metallic lead. Owing to the environmental concerns, it was decided to use acetic acid in the presence of oxygen. The theoretical justification for this approach is the favorable redox potential for the reaction between metallic lead, acetic acid, and gaseous oxygen

  12. Electrokinetic remediation on cadmium (CD) spiked soils

    Energy Technology Data Exchange (ETDEWEB)

    Sah Jy-Gau [Dept. of Environmental Science and Engineering, National Pingtung Univ. of Science and Technology, Pingtung (Taiwan); Yu Lin, L. [Dept. of Civil and Environmental Engineering, Christian Bros. Univ. Memphis, TN (United States)

    2001-07-01

    The objective of this study is to examine several variables, such as soil pH, adsorption capacity, fraction of Cd in soils, and organic content for Cd removal in contaminated soil using electrokinetic technology. Two different experimental modules were constructed in the laboratory. In the small module, most Cd was able to move and concentrate at or near the cathode zone in acidic soil and neutral soil under 8 volts after 30 days of electrification. However, the Cd removal efficiency did not improve even when the alkaline soil was soaked in stronger acid solutions. The results indicated that the removal efficiencies were influenced not only by the pH of conducting solutions, but also the pH of the soils. The removal efficiencies of Cd were reduced when a portion of organic peat moss was added into the soils. The increases of organic content in the soils inhibit the removal efficiency in electrokinetic technology. In the larger scale module, the removal efficiency of Cd was lower than that in the smaller module during a short period of time. Nevertheless, the efficiency was improved in the larger module while 16 volts electric pressure and 180 days were applied to the module. The results also showed that the sequence of removal efficiency of the three soils in larger module followed the changes of soil pH. From this study, it concluded that electrokinetic technology has a highly potential to removal Cd in contaminated soils. Within these influence variable studies, the soil pH and organic content are the most important factor in electrokinetic technology. Keywords: Electrokinetic Technique, Heavy Metal, Cd, Soil Remediation. (orig.)

  13. Update on the National Groundwater and Soil Remediation Program (GASReP)

    International Nuclear Information System (INIS)

    Lye, A.

    1992-01-01

    The national Groundwater and Soil Remediation Program (GASReP), supported jointly by government and the petroleum industry, targets research on innovative ways to clean up groundwater and soil contaminated with petroleum hydrocarbons, and conducts technology transfer sessions. Within its broad context as an initiative for research, development and demonstration of innovative cleanup technologies, GASReP now targets basic applied research and/or technology development only. Industry partners and other government programs will be encouraged to extend GASReP research findings to the final stage of technology demonstration. During 1991-92 GASReP shifted its attention from starting new projects to evaluating the program, setting a new direction, and establishing a better way to seek ideas for projects. Unlike previous years, only three projects began during this period. Two technology development projects are iron and manganese pre-treatment for pump and treat clean-up systems, and surface bioreactor to clean soil/waste contaminated with petroleum hydrocarbons. The one technology assessment project dealt with a review of six technologies for in-situ bioremediation of BTEX (benzene, toluene, ethylbenzene, xylene) in groundwater. Current program direction, interests, and research needs are summarized, and candidate proposals for project selection in 1992-93 are listed

  14. Review on utilization of biochar for metal-contaminated soil and sediment remediation.

    Science.gov (United States)

    Wang, Mingming; Zhu, Yi; Cheng, Lirong; Andserson, Bruce; Zhao, Xiaohui; Wang, Dayang; Ding, Aizhong

    2018-01-01

    Biochar is a carbon-neutral or even carbon-negative material produced through thermal decomposition of plant- and animal-based biomass under oxygen-limited conditions. Recently, there has been an increasing interest in the application of biochar as an adsorbent, soil ameliorant and climate mitigation approach in many types of applications. Metal-contaminated soil remediation using biochar has been intensively investigated in small-scale and pilot-scale trials with obtained beneficial results and multifaceted effects. But so far, the study and application of biochar in contaminated sediment management has been very limited, and this is also a worldwide problem. Nonetheless, there is reason to believe that the same multiple benefits can also be realized with these sediments due to similar mechanisms for stabilizing contaminants. This paper provides a review on current biochar properties and its use as a sorbent/amendment for metal-contaminated soil/sediment remediation and its effect on plant growth, fauna habits as well as microorganism communities. In addition, the use of biochar as a potential strategy for contaminated sediment management is also discussed, especially as regards in-situ planning. Finally, we highlight the possibility of biochar application as an effective amendment and propose further research directions to ensure the safe and sustainable use of biochar as an amendment for remediation of contaminated soil and sediment. Copyright © 2017. Published by Elsevier B.V.

  15. Phytostabilisation-A Sustainable Remediation Technique for Zinc in Soils

    Energy Technology Data Exchange (ETDEWEB)

    Padmavathiamma, Prabha [University of British Columbia, Faculty of Land and Food Systems (Canada); Li, Loretta, E-mail: lli@civil.ubc.c [University of British Columbia, Department of Civil Engineering (Canada)

    2009-08-15

    Two studies were conducted to determine a feasible and practical phytoremediation strategy for Zn-contaminated soils. The aim of the first study was to identify promising plant species capable of Zn remediation for the soils and climatic conditions of British Columbia. The purpose of the second study was to assess the effects of soil amendments in modifying the soil properties and providing the right conditions for the plants to immobilise Zn. Promising plants for phytostabilisation in the first study (Lolium perenne, Festuca rubra and Poa pratensis) were tested in the presence of soil amendments (lime, phosphate and compost, both individually and in combination) in the second study. The efficiency of treatments to stabilise Zn was based on Zn fractionation in the soil and on absorption and partitioning of Zn in plants. Maximum Zn immobilisation was achieved in the soil by a combination of lime, phosphate and compost, in conjunction with growth of P. pratensis.

  16. Characteristics of soil under variations in clay, water saturation, and water flow rates, and the implications upon soil remediation

    International Nuclear Information System (INIS)

    Aikman, M.; Mirotchnik, K.; Kantzas, A.

    1997-01-01

    A potential remediation method for hydrocarbon contaminated soils was discussed. The new method was based on the use of proven and economic petroleum reservoir engineering methods for soil remediation. The methods that were applied included water and gas displacement methods together with horizontal boreholes as the flow inlet and outlets. This system could be used in the case of spills that seep beneath a plant or other immovable infrastructure which requires in-situ treatment schemes to decontaminate the soil. A study was conducted to characterize native soils and water samples from industrial plants in central Alberta and Sarnia, Ontario and to determine the variables that impact upon the flow conditions of synthetic test materials. The methods used to characterize the soils included X-Ray computed tomographic analysis, grain size and density measurements, and X-Ray diffraction. Clay content, initial water saturation, and water and gas flow rate were the variables that impacted on the flow conditions

  17. Stability of immobilization remediation of several amendments on cadmium contaminated soils as affected by simulated soil acidification.

    Science.gov (United States)

    Guo, Fuyu; Ding, Changfeng; Zhou, Zhigao; Huang, Gaoxiang; Wang, Xingxiang

    2018-06-04

    Chemical immobilization is a practical approach to remediate heavy metal contamination in agricultural soils. However, the potential remobilization risks of immobilized metals are a major environmental concern, especially in acid rain zones. In the present study, changes in the immobilization efficiency of several amendments as affected by simulated soil acidification were investigated to evaluate the immobilization remediation stability of several amendments on two cadmium (Cd) contaminated soils. Amendments (hydrated lime, hydroxyapatite and biochar) effectively immobilized Cd, except for organic fertilizer, and their immobilizations were strongly decreased by the simulated soil acidification. The ratio of changes in CaCl 2 -extractable Cd: pH (△CaCl 2 -Cd/△pH) can represent the Cd remobilization risk of different amended soils. Hydroxyapatite and biochar had a stronger durable immobilizing effect than did hydrated lime, particularly in soil with a lower pH buffering capacity, which was further confirmed by the Cd concentration and accumulation in lettuce. These results can be attributed to that hydroxyapatite and biochar transformed greater proportions of exchangeable Cd to other more stable fractions than lime. After 48 weeks of incubation, in soil with a lower pH buffering capacity, the immobilization efficiencies of lime, hydroxyapatite, biochar and organic fertilizer in the deionized water group (pH 6.5) were 71.7%, 52.7%, 38.6% and 23.9%, respectively, and changed to 19.1%, 33.6%, 26.5% and 5.0%, respectively, in the simulated acid rain group (pH 2.5). The present study provides a simple method to preliminarily estimate the immobilization efficiency of amendments and predict their stability in acid rain regions before large-scale field application. In addition, hydrated lime is recommended to be combined with other acid-stable amendments (such as hydroxyapatite or biochar) to remediate heavy metal-contaminated agricultural soils in acid precipitation

  18. Cr (VI) remediation by indigenous bacteria in soils contaminated by chromium-containing slag

    International Nuclear Information System (INIS)

    Chai Liyuan; Huang Shunhong; Yang Zhihui; Peng Bing; Huang Yan; Chen Yuehui

    2009-01-01

    Hexavalent chromium (Cr) is a toxic element causing serious environmental threat. Recently, more and more attention is paid to the bio-remediation of Cr (VI) in the contaminated soils. Cr (VI) remediation by indigenous bacteria in soils contaminated by chromium-containing slag at a steel-alloy factory in Hunan Province, China, was investigated in the present study. The results showed that when sufficient nutrients were amended into the contaminated soils, total Cr (VI) concentration declined from the initial value of 462.8 to 10 mg kg -1 at 10 days and the removal rate was 97.8%. Water soluble Cr (VI) decreased from the initial concentration of 383.8 to 1.7 mg kg -1 . Exchangeable Cr (VI) and carbonates-bound Cr (VI) were removed by 92.6% and 82.4%, respectively. Meanwhile, four Cr (VI) resistant bacterial strains were isolated from the soil under the chromium-containing slag. Only one strain showed a high ability for Cr (VI) reduction in liquid culture. This strain was identified as Pannonibacter phragmitetus sp. by gene sequencing of 16S rRNA. X-ray photoelectron spectroscope (XPS) analysis indicated that Cr (VI) was reduced into trivalent chromium. The results suggest that indigenous bacterial strains have potential application for Cr (VI) remediation in the soils contaminated by chromium-containing slag.

  19. Aerobic and anaerobic biosynthesis of nano-selenium for remediation of mercury contaminated soil.

    Science.gov (United States)

    Wang, Xiaonan; Zhang, Daoyong; Pan, Xiangliang; Lee, Duu-Jong; Al-Misned, Fahad A; Mortuza, M Golam; Gadd, Geoffrey Michael

    2017-03-01

    Selenium (Se) nanoparticles are often synthesized by anaerobes. However, anaerobic bacteria cannot be directly applied for bioremediation of contaminated top soil which is generally aerobic. In this study, a selenite-reducing bacterium, Citrobacter freundii Y9, demonstrated high selenite reducing power and produced elemental nano-selenium nanoparticles (nano-Se 0 ) under both aerobic and anaerobic conditions. The biogenic nano-Se 0 converted 45.8-57.1% and 39.1-48.6% of elemental mercury (Hg 0 ) in the contaminated soil to insoluble mercuric selenide (HgSe) under anaerobic and aerobic conditions, respectively. Addition of sodium dodecyl sulfonate enhanced Hg 0 remediation, probably owing to the release of intracellular nano-Se 0 from the bacterial cells for Hg fixation. The reaction product after remediation was identified as non-reactive HgSe that was formed by amalgamation of nano-Se 0 and Hg 0 . Biosynthesis of nano-Se 0 both aerobically and anaerobically therefore provides a versatile and cost-effective remediation approach for Hg 0 -contaminated surface and subsurface soils, where the redox potential often changes dramatically. Copyright © 2016. Published by Elsevier Ltd.

  20. Innovative fossil fuel fired vitrification technology for soil remediation

    International Nuclear Information System (INIS)

    1993-08-01

    Vortex has successfully completed Phase 1 of the ''Innovative Fossil Fuel Fired Vitrification Technology for Soil Remediation'' program with the Department of Energy (DOE) Morgantown Energy Technology Center (METC). The Combustion and Melting System (CMS) has processed 7000 pounds of material representative of contaminated soil that is found at DOE sites. The soil was spiked with Resource Conversation and Recovery Act (RCRA) metals surrogates, an organic contaminant, and a surrogate radionuclide. The samples taken during the tests confirmed that virtually all of the radionuclide was retained in the glass and that it did not leach to the environment. The organic contaminant, anthracene, was destroyed during the test with a Destruction and Removal Efficiency (DRE) of at least 99.99%. RCRA metal surrogates, that were in the vitrified product, were retained and will not leach to the environment--as confirmed by the TCLP testing. Semi-volatile RCRA metal surrogates were captured by the Air Pollution Control (APC) system, and data on the amount of metal oxide particulate and the chemical composition of the particulate were established for use in the Phase 2 APC system design. This topical report will present a summary of the activities conducted during Phase 1 of the ''Innovative Fossil Fuel Fired Vitrification Technology for Soil Remediation'' program. The report includes the detail technical data generated during the experimental program and the design and cost data for the preliminary Phase 2 plant

  1. Ricinus communis L. A Value Added Crop for Remediation of Cadmium Contaminated Soil.

    Science.gov (United States)

    Bauddh, Kuldeep; Singh, Kripal; Singh, Rana P

    2016-02-01

    Heavy metal pollution of soil is a global environmental problem and therefore its remediation is of paramount importance. Cadmium (Cd) is a potential toxicant to living organisms and even at very low concentrations. This study was aimed to assess the effectiveness of Ricinus communis for remediation of Cd contaminated soils. For this, growth and biomass of R. communis and Cd accumulation, translocation and partitioning in different plant parts were investigated after 8 months of plant growth in Cd contaminated soil (17.50 mg Cd kg−1 soil). Eight months old plants stabilized 51 % Cd in its roots and rest of the metal was transferred to the stem and leaves. There were no significant differences in growth, biomass and yield between control and Cd treated plants, except fresh weight of shoots. The seed yield per plant was reduced only by 5 % of Cd contaminated plants than control. The amount of Cd translocated to the castor seeds was nominal i.e. 0.007 µg Cd g−1 seeds. The bioconcentration factor reduced significantly in shoots and seeds in comparison to roots. The data indicates that R. communis is highly tolerant to Cd contamination and can be used for remediation of heavy metal polluted sites.

  2. Effect of pulse current on energy consumption and removal of heavy metals during electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Sun, Tian Ran

    pathways to unacceptable dosages, leading to intolerable adverse effects on both public health and the environment. In the last decades, soil and water remediation have gained growing awareness, as the necessity becomes clearer for development of such techniques for elimination of the negative impact from......: transport of water (electroosmosis) and ions (electromigration), with electromigration being the most important transport process when treating heavy metal contaminated soils. Electrodialytic remediation (EDR), one of the enhanced electrochemical remediation techniques, is developed at the Technical...... compartments. Therefore no current is wasted for carrying ions from one electrode compartment to the other. The EDR technique has been tested for decontamination of a variety of different heavy metal polluted particulate materials: mine tailings, soil, different types of fly ashes, sewage sludge, freshwater...

  3. Evaluation methods for assessing effectiveness of in situ remediation of soil and sediment contaminated with organic pollutants and heavy metals.

    Science.gov (United States)

    Song, Biao; Zeng, Guangming; Gong, Jilai; Liang, Jie; Xu, Piao; Liu, Zhifeng; Zhang, Yi; Zhang, Chen; Cheng, Min; Liu, Yang; Ye, Shujing; Yi, Huan; Ren, Xiaoya

    2017-08-01

    Soil and sediment contamination has become a critical issue worldwide due to its great harm to the ecological environment and public health. In recent years, many remediation technologies including physical, chemical, biological, and combined methods have been proposed and adopted for the purpose of solving the problems of soil and sediment contamination. However, current research on evaluation methods for assessing these remediation technologies is scattered and lacks valid and integrated evaluation methods for assessing the remediation effectiveness. This paper provides a comprehensive review with an environmental perspective on the evaluation methods for assessing the effectiveness of in situ remediation of soil and sediment contaminated with organic pollutants and heavy metals. The review systematically summarizes recent exploration and attempts of the remediation effectiveness assessment based on the content of pollutants, soil and sediment characteristics, and ecological risks. Moreover, limitations and future research needs of the practical assessment are discussed. These limitations are not conducive to the implementation of the abatement and control programs for soil and sediment contamination. Therefore, more attention should be paid to the evaluation methods for assessing the remediation effectiveness while developing new in situ remediation technologies in future research. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. In-situ remediation of brine impacted soils and groundwater using hydraulic fracturing, desalinization and recharge wells

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, C. [Wiebe Environmental Services Inc., Calgary, AB (Canada); Ratiu, I. [GeoGrid Environmental Inc., Calgary, AB (Canada)

    2006-07-01

    This conference presentation focused on the in-stu remediation of brine impacted soils and groundwater using hydraulic fracturing, desalinization and recharge wells. A former oil battery was established in the 1940s, decommissioned in the late 1960s with a reclamation certificate issued in 1972. The land owner reported poor vegetative growth in the former battery area. The purpose of the study was to investigate the cause of poor growth and delineate contaminants of concern and to remediate impacted soil and groundwater associated with the former battery site. The investigation involved agrological, geophysical and hydrogeological investigation into the extent of anthropogenic impacts as well as the development of remediation options and plans to deal with issues of concern. The presentation provided the results of the investigation, options identified, and discussed limitation on salt remediation and treatment of saline soils. Other topics included hydraulic fracturing, injection wells that were installed to re-circulate treated groundwater though the salt plume, desalinization processes, and next steps. figs.

  5. Natural remediation of an unremediated soil twelve years after a mine accident: trace element mobility and plant composition.

    Science.gov (United States)

    Burgos, Pilar; Madejón, Paula; Madejón, Engracia; Girón, Ignacio; Cabrera, Francisco; Murillo, José Manuel

    2013-01-15

    The long-term influence of a mine spill in soil was studied 12 years after the Aznalcóllar accident. Soils where the pyritic sludge was not removed, a fenced plot established for research purposes (2000 m(2)) and soils where the process of remediation was accomplished successfully were sampled and studied in detail. Soils were characterized at different depths, down to 100 cm depth, determining chemical parameters and total concentrations of major and trace elements. Moreover plants colonizing remediated (RE) and non remediated (NRE) soils were also analysed attending their potential risk for herbivores. Strong acidification was observed in the NRE soil except in surface (0-10 cm). The progressive colonization of natural vegetation, more than 90% of the fenced plot covered by plants, could facilitate this increased pH values in the top soil (pH 6). In the NRE soil, the successive oxidation and hydrolysis of sulphide in the deposited sludge on the surface after the accident resulted in a re-dissolution of the most mobile element (Cd, Cu and Zn) and a penetration to deeper layers. Trace element concentrations in plants growing in the NRE soil showed normal contents for higher plants and tolerable for livestock. Nitrogen and mineral nutrients were of the same order in both soils, and also normal for high plants and adequate for animal nutrition. Despite of the natural remediation of the NRE soil, results demonstrate that the remediation tasks carried out in all the area, the Guadiamar Green Corridor at present, were necessary to avoid the leaching of the most mobile elements and minimize the risk of contamination of groundwater sources, many of them close to the Doñana National Park. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Remediation of Heavy Metal(loid)s Contaminated Soils – To Mobilize or To Immobilize?

    Science.gov (United States)

    Unlike organic contaminants, metal(loid)s do not undergo microbial or chemical degradation and persist for a long time after their introduction. Bioavailability of metal(loid)s plays a vital role in the remediation of contaminated soils. In this review, the remediation of heavy ...

  7. Action of Canavalia ensiformis in remediation of contaminated soil with sulfentrazone

    Directory of Open Access Journals (Sweden)

    João Carlos Madalão

    Full Text Available ABSTRACT This study evaluated the jack bean (Canavalia ensiformis as a potential remediator of sulfentrazone in the soil. The experiment was conducted under field conditions in a complete randomised block design. The treatments consisted of soils with and without herbicide application as well as the absence and presence of C. ensiformis cultivation associated with incorporation into the soil or the removal of shoots of C. ensiformis. Sorghum was planted as a bioindicator to evaluate the remediation efficiency of jack bean. Sulfentrazone application in areas without C. ensiformis cultivation decreased plants stands, productivity, and height of sorghum compared to treatments where C. ensiformis was cultivated. Sorghum cultivated in succession to C. ensiformis in areas contaminated with sulfentrazone resulted in dry matter production, plants numbers, productivity, and height of sorghum equivalent to uncontaminated areas. The results of this research indicate that the use of jack bean for the bioremediation of sulfentrazone treated soils would provide greater security in the planting of susceptible species in areas where this herbicide has been applied. The cultivation of C. ensiformis in contaminated areas may reduce the risk of environmental impacts caused by sulfentrazone.

  8. Electrochemical EDTA recycling with sacrificial Al anode for remediation of Pb contaminated soil

    International Nuclear Information System (INIS)

    Pociecha, Maja; Lestan, Domen

    2010-01-01

    Recycling chelant is a precondition for cost-effective EDTA-based soil remediation. Extraction with EDTA removed 67.5% of Pb from the contaminated soil and yielded washing solution with 1535 mg L -1 Pb and 33.4 mM EDTA. Electrochemical treatment of the washing solution using Al anode, current density 96 mA cm -2 and pH 10 removed 90% of Pb from the solution (by electrodeposition on the stainless steel cathode) while the concentration of EDTA in the treated solution remained the same. The obtained data indicate that the Pb in the EDTA complex was replaced by electro-corroded Al after electro-reduction of the EDTA and subsequently removed from the solution. Additional soil extraction with the treated washing solution resulted in total removal of 87% of Pb from the contaminated soil. The recycled EDTA retained the Pb extraction potential through several steps of soil extraction and washing solution treatment, although part of the EDTA was lost by soil absorption. - Aluminium anode at alkaline pH in conventional electrolytic cell enables efficient recycling of EDTA as a part of soil washing remediation technology.

  9. Sustainability likelihood of remediation options for metal-contaminated soil/sediment.

    Science.gov (United States)

    Chen, Season S; Taylor, Jessica S; Baek, Kitae; Khan, Eakalak; Tsang, Daniel C W; Ok, Yong Sik

    2017-05-01

    Multi-criteria analysis and detailed impact analysis were carried out to assess the sustainability of four remedial alternatives for metal-contaminated soil/sediment at former timber treatment sites and harbour sediment with different scales. The sustainability was evaluated in the aspects of human health and safety, environment, stakeholder concern, and land use, under four different scenarios with varying weighting factors. The Monte Carlo simulation was performed to reveal the likelihood of accomplishing sustainable remediation with different treatment options at different sites. The results showed that in-situ remedial technologies were more sustainable than ex-situ ones, where in-situ containment demonstrated both the most sustainable result and the highest probability to achieve sustainability amongst the four remedial alternatives in this study, reflecting the lesser extent of off-site and on-site impacts. Concerns associated with ex-situ options were adverse impacts tied to all four aspects and caused by excavation, extraction, and off-site disposal. The results of this study suggested the importance of considering the uncertainties resulting from the remedial options (i.e., stochastic analysis) in addition to the overall sustainability scores (i.e., deterministic analysis). The developed framework and model simulation could serve as an assessment for the sustainability likelihood of remedial options to ensure sustainable remediation of contaminated sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Leaching of Contamination from Stabilization/Solidification Remediated Soils of Different Texture

    Science.gov (United States)

    Burlakovs, Juris; Kasparinskis, Raimonds; Klavins, Maris

    2012-09-01

    Development of soil and groundwater remediation technologies is a matter of great importance to eliminate historically and currently contaminated sites. Stabilization/solidification (S/S) refers to binding of waste contaminants to a more chemically stable form and thus diminishing leaching of contamination. It can be performed using cement with or without additives in order to stabilize and solidify soil with the contamination in matrix. A series of experiments were done to determine leaching properties of spiked soils of different texture bound with cement. Results of experiments showed, that soil texture (content of sand, silt and clay particles) affects the leaching of heavy metals from stabilized soils.

  11. Eisenia fetida avoidance behavior as a tool for assessing the efficiency of remediation of Pb, Zn and Cd polluted soil

    International Nuclear Information System (INIS)

    Udovic, Metka; Lestan, Domen

    2010-01-01

    Remediation by means of soil leaching with ethylenediaminetetraacetic acid (EDTA) is capable of extracting the most labile soil fractions, leaving the residual metals in biologically non-available forms. We evaluated the feasibility of the standardized earthworm (Eisenia fetida) avoidance test for assessing the efficiency of soil remediation of Pb, Zn and Cd polluted soil. Chemical extraction tests (six-step sequential extraction, toxicity characteristic leaching procedure, physiologically based extraction test, diethylenediaminepentaacetic acid extraction) indicated that the mobility, oral bioaccessibility and phytoavailability of Pb, Zn and Cd were consistently reduced. However, the avoidance test showed no significant avoidance of polluted soil in favor of that which had been remediated. Pb, Zn and Cd accumulation in E. fetida mirrored the decreasing pattern of metal potential bioavailability gained by leaching the soil with increasing EDTA concentrations. The calculated bioaccumulation factors indicated the possibility of underestimating the metal bioavailability in soil using chemical extraction tests. - Tests with indicator organisms should be used for a more meaningful and holistic assessment of metal biological availability in polluted and remediated soil.

  12. Eisenia fetida avoidance behavior as a tool for assessing the efficiency of remediation of Pb, Zn and Cd polluted soil

    Energy Technology Data Exchange (ETDEWEB)

    Udovic, Metka [Centre for Soil and Environmental Science, Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, Sl-1000 Ljubljana (Slovenia); Lestan, Domen, E-mail: domen.lestan@bf.uni-lj.s [Centre for Soil and Environmental Science, Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, Sl-1000 Ljubljana (Slovenia)

    2010-08-15

    Remediation by means of soil leaching with ethylenediaminetetraacetic acid (EDTA) is capable of extracting the most labile soil fractions, leaving the residual metals in biologically non-available forms. We evaluated the feasibility of the standardized earthworm (Eisenia fetida) avoidance test for assessing the efficiency of soil remediation of Pb, Zn and Cd polluted soil. Chemical extraction tests (six-step sequential extraction, toxicity characteristic leaching procedure, physiologically based extraction test, diethylenediaminepentaacetic acid extraction) indicated that the mobility, oral bioaccessibility and phytoavailability of Pb, Zn and Cd were consistently reduced. However, the avoidance test showed no significant avoidance of polluted soil in favor of that which had been remediated. Pb, Zn and Cd accumulation in E. fetida mirrored the decreasing pattern of metal potential bioavailability gained by leaching the soil with increasing EDTA concentrations. The calculated bioaccumulation factors indicated the possibility of underestimating the metal bioavailability in soil using chemical extraction tests. - Tests with indicator organisms should be used for a more meaningful and holistic assessment of metal biological availability in polluted and remediated soil.

  13. Towards successful bioaugmentation with entrapped cells as a soil remediation technology

    DEFF Research Database (Denmark)

    Owsianiak, Mikolaj; Dechesne, Arnaud; Binning, Philip John

    2010-01-01

    Soil remediation technologies are proposed that rely on inoculation with degrading microorganisms entrapped in protective carriers. A mathematical model developed to model entrapped cell bioaugmentation describes the 3-D diffusion-driven mass transfer of benzoate, and its mineralization...... but is restricted in dry conditions, as confirmed by performing cell counts. This highlights the potential of entrapped cells when they act as seeds for soil colonization....

  14. When is a soil remediated? Comparison of biopiled and windrowed soils contaminated with bunker-fuel in a full-scale trial

    Energy Technology Data Exchange (ETDEWEB)

    Coulon, Frederic [Centre for Resource Management and Efficiency, Sustainable Systems Department, School of Applied Sciences, Cranfield University, Cranfield MK43 0AL (United Kingdom); Al Awadi, Mohammed; Cowie, William [Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen AB24 3UU (United Kingdom); Mardlin, David [Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen AB24 3UU (United Kingdom); Remedios Limited, Campus 3, Unit E2, Aberdeen Science and Technology Park, Aberdeen AB22 8GW (United Kingdom); Pollard, Simon [Centre for Resource Management and Efficiency, Sustainable Systems Department, School of Applied Sciences, Cranfield University, Cranfield MK43 0AL (United Kingdom); Cunningham, Colin [CLARRC, John Muir Building, The Kings Buildings, University of Edinburgh, Edinburgh EH9 3LJ (United Kingdom); Risdon, Graeme [TES Bretby, Bretby Business Park, Ashby Road, Burton upon Trent DE15 0YZ (United Kingdom); Arthur, Paul [Remedios Limited, Campus 3, Unit E2, Aberdeen Science and Technology Park, Aberdeen AB22 8GW (United Kingdom); Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Semple, Kirk T., E-mail: k.semple@lancaster.ac.u [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Paton, Graeme I. [Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen AB24 3UU (United Kingdom); Remedios Limited, Campus 3, Unit E2, Aberdeen Science and Technology Park, Aberdeen AB22 8GW (United Kingdom)

    2010-10-15

    A six month field scale study was carried out to compare windrow turning and biopile techniques for the remediation of soil contaminated with bunker C fuel oil. End-point clean-up targets were defined by human risk assessment and ecotoxicological hazard assessment approaches. Replicate windrows and biopiles were amended with either nutrients and inocula, nutrients alone or no amendment. In addition to fractionated hydrocarbon analysis, culturable microbial characterisation and soil ecotoxicological assays were performed. This particular soil, heavy in texture and historically contaminated with bunker fuel was more effectively remediated by windrowing, but coarser textures may be more amendable to biopiling. This trial reveals the benefit of developing risk and hazard based approaches in defining end-point bioremediation of heavy hydrocarbons when engineered biopile or windrow are proposed as treatment option. - Windrows outperform biopiles in the bioremediation of bunker oil contaminated soils.

  15. When is a soil remediated? Comparison of biopiled and windrowed soils contaminated with bunker-fuel in a full-scale trial

    International Nuclear Information System (INIS)

    Coulon, Frederic; Al Awadi, Mohammed; Cowie, William; Mardlin, David; Pollard, Simon; Cunningham, Colin; Risdon, Graeme; Arthur, Paul; Semple, Kirk T.; Paton, Graeme I.

    2010-01-01

    A six month field scale study was carried out to compare windrow turning and biopile techniques for the remediation of soil contaminated with bunker C fuel oil. End-point clean-up targets were defined by human risk assessment and ecotoxicological hazard assessment approaches. Replicate windrows and biopiles were amended with either nutrients and inocula, nutrients alone or no amendment. In addition to fractionated hydrocarbon analysis, culturable microbial characterisation and soil ecotoxicological assays were performed. This particular soil, heavy in texture and historically contaminated with bunker fuel was more effectively remediated by windrowing, but coarser textures may be more amendable to biopiling. This trial reveals the benefit of developing risk and hazard based approaches in defining end-point bioremediation of heavy hydrocarbons when engineered biopile or windrow are proposed as treatment option. - Windrows outperform biopiles in the bioremediation of bunker oil contaminated soils.

  16. Recent advances in conventional and contemporary methods for remediation of heavy metal-contaminated soils.

    Science.gov (United States)

    Sharma, Swati; Tiwari, Sakshi; Hasan, Abshar; Saxena, Varun; Pandey, Lalit M

    2018-04-01

    Remediation of heavy metal-contaminated soils has been drawing our attention toward it for quite some time now and a need for developing new methods toward reclamation has come up as the need of the hour. Conventional methods of heavy metal-contaminated soil remediation have been in use for decades and have shown great results, but they have their own setbacks. The chemical and physical techniques when used singularly generally generate by-products (toxic sludge or pollutants) and are not cost-effective, while the biological process is very slow and time-consuming. Hence to overcome them, an amalgamation of two or more techniques is being used. In view of the facts, new methods of biosorption, nanoremediation as well as microbial fuel cell techniques have been developed, which utilize the metabolic activities of microorganisms for bioremediation purpose. These are cost-effective and efficient methods of remediation, which are now becoming an integral part of all environmental and bioresource technology. In this contribution, we have highlighted various augmentations in physical, chemical, and biological methods for the remediation of heavy metal-contaminated soils, weighing up their pros and cons. Further, we have discussed the amalgamation of the above techniques such as physiochemical and physiobiological methods with recent literature for the removal of heavy metals from the contaminated soils. These combinations have showed synergetic effects with a many fold increase in removal efficiency of heavy metals along with economic feasibility.

  17. In-situ remediation system for groundwater and soils

    Science.gov (United States)

    Corey, John C.; Kaback, Dawn S.; Looney, Brian B.

    1993-01-01

    A method and system for in-situ remediation of contaminated groundwater and soil where the contaminants, such as toxic metals, are carried in a subsurface plume. The method comprises selection and injection into the soil of a fluid that will cause the contaminants to form stable, non-toxic compounds either directly by combining with the contaminants or indirectly by creating conditions in the soil or changing the conditions of the soil so that the formation of stable, non-toxic compounds between the contaminants and existing substances in the soil are more favorable. In the case of non-toxic metal contaminants, sulfides or sulfates are injected so that metal sulfides or sulfates are formed. Alternatively, an inert gas may be injected to stimulate microorganisms in the soil to produce sulfides which, in turn, react with the metal contaminants. Preferably, two wells are used, one to inject the fluid and one to extract the unused portion of the fluid. The two wells work in combination to create a flow of the fluid across the plume to achieve better, more rapid mixing of the fluid and the contaminants.

  18. Thermal Treatment of Hydrocarbon-Impacted Soils: A Review of Technology Innovation for Sustainable Remediation

    Directory of Open Access Journals (Sweden)

    Julia E. Vidonish

    2016-12-01

    Full Text Available Thermal treatment technologies hold an important niche in the remediation of hydrocarbon-contaminated soils and sediments due to their ability to quickly and reliably meet cleanup standards. However, sustained high temperature can be energy intensive and can damage soil properties. Despite the broad applicability and prevalence of thermal remediation, little work has been done to improve the environmental compatibility and sustainability of these technologies. We review several common thermal treatment technologies for hydrocarbon-contaminated soils, assess their potential environmental impacts, and propose frameworks for sustainable and low-impact deployment based on a holistic consideration of energy and water requirements, ecosystem ecology, and soil science. There is no universally appropriate thermal treatment technology. Rather, the appropriate choice depends on the contamination scenario (including the type of hydrocarbons present and on site-specific considerations such as soil properties, water availability, and the heat sensitivity of contaminated soils. Overall, the convergence of treatment process engineering with soil science, ecosystem ecology, and plant biology research is essential to fill critical knowledge gaps and improve both the removal efficiency and sustainability of thermal technologies.

  19. Assessing the efficacy over time of the addition of industrial by-products to remediate contaminated soils at a pilot-plant scale.

    Science.gov (United States)

    González-Núñez, Raquel; Rigol, Anna; Vidal, Miquel

    2017-04-01

    The effect of the addition of industrial by-products (gypsum and calcite) on the leaching of As and metals (Cu, Zn, Ni, Pb and Cd) in a soil contaminated by pyritic minerals was monitored over a period of 6 months at a two-pit pilot plant. The contaminated soil was placed in one pit (non-remediated soil), whereas a mixture of the contaminated soil (80% w/w) with gypsum (10% w/w) and calcite (10% w/w) was placed in the other pit (remediated soil). Soil samples and leachates of the two pits were collected at different times. Moreover, the leaching pattern of major and trace elements in the soil samples was assessed at laboratory level through the application of the pH stat leaching test. Addition of the by-products led to an increase in initial soil pH from around 2.0 to 7.5, and it also provoked that the concentration of trace elements in soil extracts obtained from the pH stat leaching test decreased to values lower than quantification limits of inductively coupled plasma optical emission spectrometry and lower than the hazardous waste threshold for soil management. The trace element concentration in the pilot-plant leachates decreased over time in the non-remediated soil, probably due to the formation of more insoluble secondary minerals containing sulphur, but especially decreased in pit of the remediated soil, in agreement with laboratory data. The pH in the remediated soil remained constant over the 6-month period, and the X-ray diffraction analyses confirmed that the phases did not vary over time, thus indicating the efficacy of the addition of the by-products. This finding suggests that soil remediation may be a feasible option for the re-use of non-hazardous industrial by-products.

  20. Use of LCA as decision support for the selection of remedial strategies for remediation of contaminated soil and groundwater

    DEFF Research Database (Denmark)

    Lemming, Gitte; Hauschild, Michael Zwicky; Bjerg, Poul Løgstrup

    2009-01-01

    , there is a trade-off between obtaining local beneficial effects from the remediation and generating environmental impacts on the regional and global scale due to the remedial actions. Therefore there is a need for including the impact of soil contaminants that will potentially leach to the groundwater, e......Groundwater is the dominant source of drinking water in Denmark and the general policy is to maintain the groundwater as a clean source of drinking water. The risk of groundwater contamination is therefore often the prime reason for remediating a contaminated site. Chlorinated solvents are among...... the contaminants most frequently found to be threatening the groundwater quality in Denmark and worldwide. Life cycle assessment has recently been applied as part of decision support for contaminated site management and subsurface remediation techniques. Impacts in the groundwater compartment have only gained...

  1. In situ vadose zone remediation of petroleum-contaminated soils

    International Nuclear Information System (INIS)

    Greacen, J.R.; Finkel, D.J.

    1991-01-01

    This paper discusses a pilot-scale system treating vadose zone soils contaminated with petroleum products constructed and operated at a former petroleum bulk storage terminal in New England. A site investigation following decommissioning activities identified more than 100,000 yds of soil at the site contaminated by both No. 2 fuel oil and gasoline. Soil cleanup criteria of 50 ppm TPH and 0.25 ppm BTEX were established. A pilot-scale treatment unit with dimensions of 125 ft x 125 ft x 6 ft was constructed to evaluate the potential for in situ treatment of vadose zone soils. Contaminant levels in pilot cell soils ranged from 0 to 5,250 ppm TPH and 0.0 to 4.2 ppm BTEX. Two soil treatment methods n the pilot system were implemented; venting to treat the lighter petroleum fractions and bioremediation to treat the nonvolatile petroleum constituents. Seven soil gas probes were installed to monitor pressure and soil gas vapor concentrations in the subsurface. Changes in soil gas oxygen and carbon dioxide concentrations were used as an indirect measure of enhanced bioremediation of pilot cell soils. After operating the system for a period of 2.5 months, soil BTEX concentrations were reduced to concentrations below the remediation criteria for the site

  2. Remedial Design/Remedial Action Work Plan for Operable Units 6-05 and 10-04, Phase III

    Energy Technology Data Exchange (ETDEWEB)

    R. P. Wells

    2006-09-19

    The remedial design/remedial action for Operable Unit 6-05 (Waste Area Group 6) and Operable Unit 10-04 (Waste Area Group 10) - collectively called Operable Unit 10-04 has been divided into four phases. Phase I consists of developing and implementing institutional controls at Operable Unit 10-04 sites and developing and implementing Idaho National Laboratory-wide plans for both institutional controls and ecological monitoring. Phase II will remediate sites contaminated with trinitrotoluene and Royal Demolition Explosive. Phase III will remediate lead contamination at a gun range, and Phase IV will remediate hazards from unexploded ordnance. This Phase III remedial Design/Remedial Action Work Plan addresses the remediation of lead-contaminated soils found at the Security Training Facility (STF)-02 Gun Range located at the Idaho National Laboratory. Remediation of the STF-02 Gun Range will include excavating contaminated soils; physically separating copper and lead for recycling; returning separated soils below the remediation goal to the site; stabilizing contaminated soils, as required, and disposing of the separated soils that exceed the remediation goal; encapsulating and disposing of creosote-contaminated railroad ties and power poles; removing and disposing of the wooden building and asphalt pads found at the STF-02 Gun Range; sampling and analyzing soil to determine the excavation requirements; and when the remediation goals have been met, backfilling and contouring excavated areas and revegetating the affected area.

  3. Decontamination of Petroleum-Contaminated Soils Using The Electrochemical Technique: Remediation Degree and Energy Consumption.

    Science.gov (United States)

    Streche, Constantin; Cocârţă, Diana Mariana; Istrate, Irina-Aura; Badea, Adrian Alexandru

    2018-02-19

    Currently, there are different remediation technologies for contaminated soils, but the selection of the best technology must be not only the treatment efficiency but also the energy consumption (costs) during its application. This paper is focused on assessing energy consumption related to the electrochemical treatment of polluted soil with petroleum hydrocarbons. In the framework of a research project, two types of experiments were conducted using soil that was artificially contaminated with diesel fuel at the same level of contamination. The experimental conditions considered for each experiment were: different amounts of contaminated soils (6 kg and 18 kg, respectively), the same current intensity level (0.25A and 0.5A), three different contamination degrees (1%, 2.5% and 5%) and the same time for application of the electrochemical treatment. The remediation degree concerning the removal of petroleum hydrocarbons from soil increased over time by approximately 20% over 7 days. With regard to energy consumption, the results revealed that with an increase in the quantity of treated soil of approximately three times, the specific energy consumption decreased from 2.94 kWh/kg treated soil to 1.64 kWh/kg treated soil.

  4. Innovative vitrification for soil remediation

    Energy Technology Data Exchange (ETDEWEB)

    Jetta, N.W.; Patten, J.S.; Hnat, J.G. [Vortec Corp., Collegeville, PA (United States)

    1995-10-01

    The objective of this DOE demonstration program is to validate the performance and operation of the Vortec Cyclone Melting System (CMS{trademark}) for the processing of LLW contaminated soils found at DOE sites. This DOE vitrification demonstration project has successfully progressed through the first two phases. Phase I consisted of pilot scale testing with surrogate wastes and the conceptual design of a process plant operating at a generic DOE site. The objective of Phase 2, which is scheduled to be completed the end of FY 95, is to develop a definitive process plant design for the treatment of wastes at a specific DOE facility. During Phase 2, a site specific design was developed for the processing of LLW soils and muds containing TSCA organics and RCRA metal contaminants. Phase 3 will consist of a full scale demonstration at the DOE gaseous diffusion plant located in Paducah, KY. Several DOE sites were evaluated for potential application of the technology. Paducah was selected for the demonstration program because of their urgent waste remediation needs as well as their strong management and cost sharing financial support for the project.

  5. Remediation of cadmium contaminated water and soil using vinegar residue biochar.

    Science.gov (United States)

    Li, Yuxin; Pei, Guangpeng; Qiao, Xianliang; Zhu, Yuen; Li, Hua

    2018-06-01

    This study investigated a new biochar produced from vinegar residue that could be used to remediate cadmium (Cd)-contaminated water and soil. Aqueous solution adsorption and soil incubation experiments were performed to investigate whether a biochar prepared at 700 °C from vinegar residue could efficiently adsorb and/or stabilize Cd in water and soil. In the aqueous solution adsorption experiment, the Cd adsorption process was best fitted by the pseudo-second-order kinetic and Freundlich isotherm models. If the optimum parameters were used, i.e., pH 5 or higher, a biochar dosage of 12 g L -1 , a 10 mg L -1 Cd initial concentration, and 15-min equilibrium time, at 25 °C, then Cd removal could reach about 100%. The soil incubation experiment evaluated the biochar effects at four different application rates (1, 2, 5, and 10% w/w) and three Cd contamination rates (0.5, 1, and 2.5 mg kg -1 ) on soil properties and Cd fractionation. Soil pH and organic matter increased after adding biochar, especially at the 10% application rate. At Cd pollution levels of 1.0 or 2.5 mg kg -1 , a 10% biochar application rate was most effective. At 0.5 mg Cd kg -1 soil, a 5% biochar application rate was most efficient at transforming the acid extractable and easily reducible Cd fractions to oxidizable and residual Cd. The results from this study demonstrated that biochar made from vinegar residue could be a new and promising alternative biomass-derived material for Cd remediation in water and soil.

  6. Reducing the bioavailability of cadmium in contaminated soil by dithiocarbamate chitosan as a new remediation.

    Science.gov (United States)

    Yin, Zheng; Cao, Jingjing; Li, Zhen; Qiu, Dong

    2015-07-01

    Dithiocarbamate chitosan (DTC-CTS) was used as a new amendment for remediation of cadmium (Cd)-contaminated soils to reduce the Cd bioavailability. Arabidopsis thaliana was chosen as a model plant to evaluate its efficiency. It was found that DTC-CTS could effectively improve the growth of A. thaliana. The amount of Cd up-taken by A. thaliana could be decreased by as much as 50% compared with that grown in untreated Cd-contaminated soil samples. The chlorophyll content and the aerial biomass of Arabidopsis also increased substantially and eventually returned to a level comparable to plants grown in non-contaminated soils, with the addition of DTC-CTS. These findings suggested that DTC-CTS amendment could be effective in immobilizing Cd and mitigating its accumulation in plants grown in Cd-contaminated soils, with potential application as an in situ remediation of Cd-polluted soils.

  7. Cost studies of thermally enhanced in situ soil remediation technologies

    International Nuclear Information System (INIS)

    Bremser, J.; Booth, S.R.

    1996-05-01

    This report describes five thermally enhanced technologies that may be used to remediate contaminated soil and water resources. The standard methods of treating these contaminated areas are Soil Vapor Extraction (SVE), Excavate ampersand Treat (E ampersand T), and Pump ampersand Treat (P ampersand T). Depending on the conditions at a given site, one or more of these conventional alternatives may be employed; however, several new thermally enhanced technologies for soil decontamination are emerging. These technologies are still in demonstration programs which generally are showing great success at achieving the expected remediation results. The cost savings reported in this work assume that the technologies will ultimately perform as anticipated by their developers in a normal environmental restoration work environment. The five technologies analyzed in this report are Low Frequency Heating (LF or Ohmic, both 3 and 6 phase AC), Dynamic Underground Stripping (DUS), Radio Frequency Heating (RF), Radio Frequency Heating using Dipole Antennae (RFD), and Thermally Enhanced Vapor Extraction System (TEVES). In all of these technologies the introduction of heat to the formation raises vapor pressures accelerating contaminant evaporation rates and increases soil permeability raising diffusion rates of contaminants. The physical process enhancements resulting from temperature elevations permit a greater percentage of volatile organic compound (VOC) or semi- volatile organic compound (SVOC) contaminants to be driven out of the soils for treatment or capture in a much shorter time period. This report presents the results of cost-comparative studies between these new thermally enhanced technologies and the conventional technologies, as applied to five specific scenarios

  8. Integrating removal actions and remedial actions: Soil and debris management at the Fernald Environmental Management Project

    International Nuclear Information System (INIS)

    Goidell, L.C.; Hagen, T.D.; Strimbu, M.J.; Dupuis-Nouille, E.M.; Taylor, A.C.; Weese, T.E.; Yerace, P.J.

    1996-01-01

    Since 1991, excess soil and debris generated at the Fernald Environmental management Project (FEMP) have been managed in accordance with the principles contained in a programmatic Removal Action (RvA) Work Plan (WP). This plan provides a sitewide management concept and implementation strategy for improved storage and management of excess soil and debris over the period required to design and construct improved storage facilities. These management principles, however, are no longer consistent with the directions in approved and draft Records of Decision (RODs) and anticipated in draft RODs other decision documents. A new approach has been taken to foster improved management techniques for soil and debris that can be readily incorporated into remedial design/remedial action plans. Response, Compensation and Liability Act (CERCLA) process. This paper describes the methods that were applied to address the issues associated with keeping the components of the new work plan field implementable and flexible; this is especially important as remedial design is either in its initial stages or has not been started and final remediation options could not be precluded

  9. Evaluation of Bioaugmentation with Entrapped Degrading Cells as a Soil Remediation Technology

    DEFF Research Database (Denmark)

    Owsianiak, Mikolaj; Dechesne, Arnaud; Binning, Philip John

    2010-01-01

    Soil augmentation with microbial degraders immobilized on carriers is evaluated as a potential remediation technology using a mathematical model that includes degradation within spatially distributed carriers and diffusion or advectiondispersion as contaminant mass transfer mechanisms. The total...... degraders have low intrinsic degradation rates and that only limited carrier to soil volume ratios are practically feasible, bioaugmented soils are characterized by low effective degradation ratesandcanbeconsidered fully mixed. A simple exponential model is then sufficient to predict biodegradation...

  10. Remediation of oil-contaminated soil in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Fritt-Rasmussen, Janne; Rodrigo, Ana

    Oil spill is a problem in towns in Greenland, where oil is used for heating and transport. The problem may increase in the future with expected oil exploitation in Greenlandic marine areas and related terrestrial activities. Oil undergoes natural microbial degradation in which nutrients, temperat....... Experiments have been made with excavated oil-contaminated soil from the Greenlandic town Sisimiut to study different low-tech and low-cost solutions for remediation of oil-contamination...

  11. Remediation of oil-contaminated soil in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Fritt-Rasmussen, Janne; Rodrigo, Ana P.

    Oil spill is a problem in towns in Greenland, where oil is used for heating and transport. The problem may increase in the future with expected oil exploitation in Greenlandic marine areas and related terrestrial activities. Oil undergoes natural microbial degradation in which nutrients, temperat...... have been made with excavated oil-contaminated soil from the Greenlandic town Sisimiut to study different low-tech and low-cost solutions for remediation of oil-contamination....

  12. 300-FF-1 operable unit remedial investigation phase II report: Physical separation of soils treatability study

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This report describes the approach and results of physical separations treatability tests conducted at the Hanford Site in the North Process Pond of the 300-FF-1 Operable Unit. Physical separation of soils was identified as a remediation alternative due to the potential to significantly reduce the amount of contaminated soils prior to disposal. Tests were conducted using a system developed at Hanford consisting of modified EPA equipment integrated with screens, hoppers, conveyors, tanks, and pumps from the Hanford Site. The treatability tests discussed in this report consisted of four parts, in which an estimated 84 tons of soil was processed: (1) a pre-test run to set up the system and adjust system parameters for soils to be processed; (2) a baseline run to establish the performance of the system - Test No. 1; (3) a final run in which the system was modified as a result of findings from the baseline run - Test No. 2; and (4) water treatment.

  13. 300-FF-1 operable unit remedial investigation phase II report: Physical separation of soils treatability study

    International Nuclear Information System (INIS)

    1994-04-01

    This report describes the approach and results of physical separations treatability tests conducted at the Hanford Site in the North Process Pond of the 300-FF-1 Operable Unit. Physical separation of soils was identified as a remediation alternative due to the potential to significantly reduce the amount of contaminated soils prior to disposal. Tests were conducted using a system developed at Hanford consisting of modified EPA equipment integrated with screens, hoppers, conveyors, tanks, and pumps from the Hanford Site. The treatability tests discussed in this report consisted of four parts, in which an estimated 84 tons of soil was processed: (1) a pre-test run to set up the system and adjust system parameters for soils to be processed; (2) a baseline run to establish the performance of the system - Test No. 1; (3) a final run in which the system was modified as a result of findings from the baseline run - Test No. 2; and (4) water treatment

  14. The Research of Nanoparticle and Microparticle Hydroxyapatite Amendment in Multiple Heavy Metals Contaminated Soil Remediation

    Directory of Open Access Journals (Sweden)

    Zhangwei Li

    2014-01-01

    Full Text Available It was believed that when hydroxyapatite (HAP was used to remediate heavy metal-contaminated soils, its effectiveness seemed likely to be affected by its particle size. In this study, a pot trial was conducted to evaluate the efficiency of two particle sizes of HAP: nanometer particle size of HAP (nHAP and micrometer particle size of HAP (mHAP induced metal immobilization in soils. Both mHAP and nHAP were assessed for their ability to reduce lead (Pb, zinc (Zn, copper (Cu, and chromium (Cr bioavailability in an artificially metal-contaminated soil. The pakchoi (Brassica chinensis L. uptake and soil sequential extraction method were used to determine the immobilization and bioavailability of Pb, Zn, Cu, and Cr. The results indicated that both mHAP and nHAP had significant effect on reducing the uptake of Pb, Zn, Cu, and Cr by pakchoi. Furthermore, both mHAP and nHAP were efficient in covering Pb, Zn, Cu, and Cr from nonresidual into residual forms. However, mHAP was superior to nHAP in immobilization of Pb, Zn, Cu, and Cr in metal-contaminated soil and reducing the Pb, Zn, Cu, and Cr utilized by pakchoi. The results suggested that mHAP had the better effect on remediation multiple metal-contaminated soils than nHAP and was more suitable for applying in in situ remediation technology.

  15. Application of remedy studies to the development of a soil washing pilot plant that uses mineral processing technology: a practical experience

    International Nuclear Information System (INIS)

    Richardson, W.S.; Phillips, C.R.; Hicks, R.; Luttrell, J.; Cox, C.

    1999-01-01

    Soil washing employing mineral processing technology to treat radionuclide-contaminated soils has been examined as a remedy alternative to the exclusive excavation, transportation, and disposal of the soil. Successful application depends on a thorough remedy study, employing a systematic tiered approach that is efficient, self-limiting, and cost effective. The study includes: (1) site and soil characterization to determine the basic mineral and physical properties of both the soil and contaminants and to identify their relative associations; (2) treatment studies to evaluate the performance of process units for contaminant separation; (3) conceptual process design to develop a treatment pilot plant; and (4) engineering design to construct, test, and optimize the actual full-scale plant. A pilot plant using soil washing technology for the treatment of radium-contaminated soil was developed, tested, and demonstrated. The plant used particle-size separation to produced a remediated product that represented approximately 50% of the contaminated soil. Subsequently, it was modified for more effective performance and application to soil with alternate characteristics; it awaits further testing. The economic analysis of soil washing using the pilot plant as a model indicates that a remedy plan based on mineral processing technology is very competitive with the traditional alternative employing excavation, transportation, and disposal exclusively, even when disposal costs are modest or when recovery of remediated soil during treatment is low. This paper reviews the tiered approach as it applies to mineral processing technology to treat radionuclide-contaminated soils and a pilot plant developed to test the soil washing process. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  16. Bioaccumulation in Porcellio scaber (Crustacea, Isopoda) as a measure of the EDTA remediation efficiency of metal-polluted soil

    International Nuclear Information System (INIS)

    Udovic, Metka; Drobne, Damjana; Lestan, Domen

    2009-01-01

    Leaching using EDTA applied to a Pb, Zn and Cd polluted soil significantly reduced soil metal concentrations and the pool of metals in labile soil fractions. Metal mobility (Toxicity Characteristic Leaching Procedure), phytoavailability (diethylenetriaminepentaacetic acid extraction) and human oral-bioavailability (Physiologically Based Extraction Test) were reduced by 85-92%, 68-91% and 88-95%, respectively. The metal accumulation capacity of the terrestrial isopod Porcellio scaber (Crustacea) was used as in vivo assay of metal bioavailability, before and after soil remediation. After feeding on metal contaminated soil for two weeks, P. scaber accumulated Pb, Zn and Cd in a concentration dependent manner. The amounts of accumulated metals were, however, higher than expected on the basis of extraction (in vitro) tests. The combined results of chemical extractions and the in vivo test with P. scaber provide a more relevant picture of the availability stripping of metals after soil remediation. - Bioaccumulation tests with Porcellio scaber isopods are proposed as a supplement to chemical extraction in assessing metal bioavailability before and after soil remediation.

  17. Study on adsorption and remediation of heavy metals by poplar and larch in contaminated soil.

    Science.gov (United States)

    Wang, Xin; Jia, Youngfeng

    2010-08-01

    Field experiments at the Shenyang Experimental Station of Ecology were conducted to study the adsorption, accumulation, and remediation of heavy metals by poplar and larch grown in artificially contaminated soil. The soil was spiked with a combination of Cd, Cu, and Zn at concentrations of 1.5, 100, and 200 mg.kg(-1), respectively. The results showed that the biomass of poplar (Populus canadensis Moench) was lower by 26.0% in the soil spiked with a mixture of Cd, Cu, and Zn, compared with the control. Concentrations of Cd in poplar leaf and Cu in poplar roots in the treated soil were 4.11 and 14.55 mg kg(-1), respectively, which are much greater than in corresponding controls. The migration of heavy metals in woody plant body was in the order Cd > Zn > Cu. Poplar had higher metal concentrations in aboveground tissues and a higher biomass compared with larch of the same age and therefore is potentially more suitable for remediation. In the heavy metal-polluted soil of this study, phytoremediation by poplar may take 56 and 245 years for Cd and Cu, respectively, for meeting the soil standards of heavy metals, and the corresponding phytoremediation times by larch would take 211 and 438 years. The research findings could be used as a basis to develop ecological engineering technologies for environmental control and remediation of pollution caused by heavy metals in soils.

  18. Remediation of a historically Pb contaminated soil using a model natural Mn oxide waste.

    Science.gov (United States)

    McCann, Clare M; Gray, Neil D; Tourney, Janette; Davenport, Russell J; Wade, Matthew; Finlay, Nina; Hudson-Edwards, Karen A; Johnson, Karen L

    2015-11-01

    A natural Mn oxide (NMO) waste was assessed as an in situ remediation amendment for Pb contaminated sites. The viability of this was investigated using a 10 month lysimeter trial, wherein a historically Pb contaminated soil was amended with a 10% by weight model NMO. The model NMO was found to have a large Pb adsorption capacity (qmax 346±14 mg g(-1)). However, due to the heterogeneous nature of the Pb contamination in the soils (3650.54-9299.79 mg kg(-1)), no treatment related difference in Pb via geochemistry could be detected. To overcome difficulties in traditional geochemical techniques due to pollutant heterogeneity we present a new method for unequivocally proving metal sorption to in situ remediation amendments. The method combines two spectroscopic techniques; namely electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). Using this we showed Pb immobilisation on NMO, which were Pb free prior to their addition to the soils. Amendment of the soil with exogenous Mn oxide had no effect on microbial functioning, nor did it perturb the composition of the dominant phyla. We conclude that NMOs show excellent potential as remediation amendments. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Remediation of Biological Organic Fertilizer and Biochar in Paddy Soil Contaminated by Cd and Pb

    Directory of Open Access Journals (Sweden)

    MA Tie-zheng

    2015-02-01

    Full Text Available The effect of application of biological organic fertilizer and biochar on the immobilized remediation of paddy soil contaminated by Cd and Pb was studied under the field experiment. The results showed that biological organic fertilizer and biochar increased the soil pH and soil nutrient contents, and reduced the soil available Cd and Pb concentrations significantly. The soil pH had significantly negative correla-tion with the soil available Cd and Pb contents. The application of biological organic fertilizer and biochar decreased Cd and Pb concentration in all parts of the rice plant, with Cd concentration in brown rice decrease by 22.00% and 18.34% and Pb decease in brown rice by 33.46% and 12.31%. The concentration of Cd and Pb in brown rice had significant positive correlation with the soil available Cd and Pb concentra-tions. It was observed that both biological organic fertilizer and biochar had a positive effect on the remediation of paddy soil contaminated by Cd and Pb.

  20. Phosphorus Amendment Efficacy for In Situ Remediation of Soil Lead Depends on the Bioaccessible Method

    Science.gov (United States)

    A validated method is needed to measure reductions of in vitro bioaccessible (IVBA) Pb in urban soil remediated with amendments. This study evaluated the effect of in vitro extraction solution pH and glycine buffer on bioaccesible Pb in P-treated soils. Two Pb-contaminated soils...

  1. Reliability and stability of immobilization remediation of Cd polluted soils using sepiolite under pot and field trials

    International Nuclear Information System (INIS)

    Sun, Yuebing; Xu, Yi; Xu, Yingming; Wang, Lin; Liang, Xuefeng; Li, Ye

    2016-01-01

    Long-term effectiveness and persistence are two important criterias to evaluate alternative remediation technology of heavy metal polluted soils. Pot and field studies showed addition of sepiolite was effective in immobilizing Cd in polluted soils, with significant reduction in TCLP extracts (0.6%–49.6% and 4.0%–32.5% reduction in pot and field experiments, respectively) and plant uptake (14.4%–84.1% and 22.8%–61.4% declines in pot and field studies, correspondingly). However, the applications of sepiolite offered a limited guarantee for the safety of edible vegetables in Cd-polluted soils, depending on the soil type, the Cd pollution type and level, and the dose and application frequency of chemical amendments. Bioassays, such as plant growth, soil enzymatic activities and microbial community diversity, indicated a certain degree of recovery of soil metabolic function. Therefore, sepiolite-assisted in situ remediation is cost-effective, environmentally friendly, and technically applicable, and can be successfully used to reduce Cd enter into the food chain on field scale. - Highlights: • Sepiolite has reliability and stability for remediation of contaminated Cd. • Sepiolite significantly decreases Cd bioavailability in soil and uptake in plant. • The treatment of sepiolite improves soil quality. - Sepiolite not only decreased soil Cd bioavailability and plant Cd uptake, but also improved soil quality.

  2. Leaching of Contamination from Stabilization/Solidification Remediated Soils of Different Texture

    OpenAIRE

    Burlakovs, J; Kasparinskis, R; Klavins, M

    2012-01-01

    Development of soil and groundwater remediation technologies is a matter of great importance to eliminate historically and currently contaminated sites. Stabilization/solidification (S/S) refers to binding of waste contaminants to a more chemically stable form and thus diminishing leaching of contamination. It can be performed using cement with or without additives in order to stabilize and solidify soil with the contamination in matrix. A series of experiments were done to determine leaching...

  3. Caresoil: A multidisciplinar Project to characterize, remediate, monitor and evaluate the risk of contaminated soils in Madrid (Spain)

    Science.gov (United States)

    Muñoz-Martín, Alfonso; Antón, Loreto; Granja, Jose Luis; Villarroya, Fermín; Montero, Esperanza; Rodríguez, Vanesa

    2016-04-01

    Soil contamination can come from diffuse sources (air deposition, agriculture, etc.) or local sources, these last being related to anthropogenic activities that are potentially soil contaminating activities. According to data from the EU, in Spain, and particularly for the Autonomous Community of Madrid, it can be considered that heavy metals, toxic organic compounds (including Non Aqueous Phases Liquids, NAPLs) and combinations of both are the main problem of point sources of soil contamination in our community. The five aspects that will be applied in Caresoil Program (S2013/MAE-2739) in the analysis and remediation of a local soil contamination are: 1) the location of the source of contamination and characterization of soil and aquifer concerned, 2) evaluation of the dispersion of the plume, 3) application of effective remediation techniques, 4) monitoring the evolution of the contaminated soil and 5) risk analysis throughout this process. These aspects involve advanced technologies (hydrogeology, geophysics, geochemistry,...) that require new developing of knowledge, being necessary the contribution of several researching groups specialized in the fields previously cited, as they are those integrating CARESOIL Program. Actually two cases concerning hydrocarbon spills, as representative examples of soil local contamination in Madrid area, are being studied. The first is being remediated and we are monitoring this process to evaluate its effectiveness. In the second location we are defining the extent of contamination in soil and aquifer to define the most effective remediation technique.

  4. Soil and groundwater remediation through the program of energy research and development at Environment Canada

    International Nuclear Information System (INIS)

    Bacchus, P.

    2005-01-01

    Research and development in groundwater and soil remediation within the federal Program of Energy Research and Development (PERD) are conducted in the context of activities related to the oil and gas industry. Contamination of groundwater and soil by the oil and gas sector affects the health of ecosystems and the economic viability of impacted lands. This paper presented an outline of remediation research and development activities associated with PERD, as well as an overview of PERD's development of improved generic remediation technologies and approaches for use by industries. In addition, issues concerning the development of key guidelines, methods and protocols for use by regulators were discussed. Science and technology efforts within PERD contribute to the development of national standards and guidelines concerning public safety and environmental needs

  5. Electrokinetic-Enhanced Remediation of Phenanthrene-Contaminated Soil Combined with Sphingomonas sp. GY2B and Biosurfactant.

    Science.gov (United States)

    Lin, Weijia; Guo, Chuling; Zhang, Hui; Liang, Xujun; Wei, Yanfu; Lu, Guining; Dang, Zhi

    2016-04-01

    Electrokinetic-microbial remediation (EMR) has emerged as a promising option for the removal of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils. The aim of this study was to enhance degradation of phenanthrene (Phe)-contaminated soils using EMR combined with biosurfactants. The electrokinetic (EK) remediation, combined with Phe-degrading Sphingomonas sp. GY2B, and biosurfactant obtained by fermentation of Pseudomonas sp. MZ01, degraded Phe in the soil with an efficiency of up to 65.1 % at the anode, 49.9 % at the cathode after 5 days of the treatment. The presence of biosurfactants, electricity, and a neutral electrolyte stimulated the growth of the degrading bacteria as shown by a rapid increase in microbial biomass with time. The electrical conductivity and pH changed little during the course of the treatment, which benefitted the growth of microorganisms and the remediation of Phe-contaminated soil. The EMR system with the addition of biosurfactant had the highest Phe removal, demonstrating the biosurfactant may enhance the bioavailability of Phe and the interaction with the microorganism. This study suggests that the EMR combined with biosurfactants can be used to enhance in situ bioremediation of PAH-contaminated soils.

  6. Application of a participative process for DSS development in soil remediation

    Science.gov (United States)

    José Blanco-Velázquez, Francisco; Muñoz-Vallés, Sara; Anaya-Romero, María

    2017-04-01

    A wide range of current legislation concerning environmental protection and public health at the national and international level include mandatory actions related to site characterization and the implementation of effective soil remediation measures. The efficiency, in terms of reliability and costs, of this kind of assessment, involves the development and linkage of integrated-harmonized databases, simulating models and specialization tools. So far, no data/knowledge engineering technologies in the academy or market provides the possibility for simulating soil remediation processes for hypothetic spatio-temporal scenarios in a harmonized manner across Europe. In this context, under the framework of RECARE (Preventing and Remediating degradation of Soils in Europe through Land Care) project, we are designing a Decision Support System (DSS) comprising a large database of knowledge including soil, climatic and socio-economic attributes, focused on soil remediation techniques that allows the user to automatically perform a more accurate quantifying of soil pollution, spatial identification of vulnerable zones and formulation of action programs to deal with the particular problem under scenarios of climate and land-use changes. The pilot study area is the Guadiamar valley (SW Spain) where the main threat is soil contamination, after a mine spill occurred on April 1998. About four hm3 of acid waters and two hm3 of mud, rich in heavy metals, were released into the Agrio and Guadiamar rivers affecting more than 4,600 ha of agricultural and pasture land. Consequently, the area was subjected to a large-scale phyto-management project, including the removal of sludge and topsoil, the addition of amendments, and plantation of native shrubs and trees. The objective of this research is to test the feasibility of the DSS concept as well as the likelihood to establish a solid high-potential innovation tool, aligned with the scientific and market strategy and within a European

  7. A laboratory test of NOM-assisted remediation of arsenic and copper contaminated soils

    DEFF Research Database (Denmark)

    Rasmussen, Signe Bonde; Jensen, Julie Katrine; Borggaard, Ole K.

    2015-01-01

    Soils contaminated by arsenic (As) and copper (Cu) must be remediated because As and Cu are non-degradable and toxic. On moderately contaminated soils, As and Cu may be removed by in-situ plant uptake (phytoremediation), whereas strongly contaminated soils must be removed and cleaned by soil...... at neutral pH to enhance in-situ phytoremediation of moderately contaminated soils. Citrate (and NTA) cannot be suggested for enhancement of on-site phytoremediation because of high mobilization rates caused by these extractants, which through leaching and runoff may lead to contamination of recipient waters...

  8. Accelerated remediation of pesticide-contaminated soil with zerovalent iron

    Energy Technology Data Exchange (ETDEWEB)

    Shea, P.J. [University of Nebraska-Lincoln, Lincoln, NE 68583-0915 (United States)]. E-mail: pshea@unl.edu; Machacek, T.A. [University of Nebraska-Lincoln, Lincoln, NE 68583-0915 (United States); Comfort, S.D. [University of Nebraska-Lincoln, Lincoln, NE 68583-0915 (United States)

    2004-11-01

    High pesticide concentrations in soil from spills or discharges can result in point-source contamination of ground and surface waters. Cost-effective technologies are needed for on-site treatment that meet clean-up goals and restore soil function. Remediation is particularly challenging when a mixture of pesticides is present. Zerovalent iron (Fe{sup 0}) has been shown to promote reductive dechlorination and nitro group reduction of a wide range of contaminants in soil and water. We employed Fe{sup 0} for on-site treatment of soil containing >1000 mg metolachlor, >55 mg alachlor, >64 mg atrazine, >35 mg pendimethalin, and >10 mg chlorpyrifos kg{sup -1}. While concentrations were highly variable within the windrowed soil, treatment with 5% (w/w) Fe{sup 0} resulted in >60% destruction of the five pesticides within 90 d and increased to >90% when 2% (w/w) Al{sub 2}(SO{sub 4}){sub 3} was added to the Fe{sup 0}. GC/MS analysis confirmed dechlorination of metolachlor and alachlor during treatment. Our observations support the use of Fe{sup 0} for ex situ treatment of pesticide-contaminated soil. - Capsule: Zerovalent iron promotes pesticide degradation in highly contaminated soil.

  9. Application of bioassays to evaluate a copper contaminated soil before and after a pilot-scale electrokinetic remediation

    Energy Technology Data Exchange (ETDEWEB)

    Wang Quanying [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Zhou Dongmei [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China)], E-mail: dmzhou@issas.ac.cn; Cang Long [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Sun Tianran [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China)

    2009-02-15

    Remediation programmes are considered to be complete when human risk-based criteria are met. However, these targets are often unsatisfied with the ecological parameters that may be important with regard to future soil use. Five soil subsamples, collecting along a pilot-scale soil column after electrokinetic treatment, were studied, from which about 42.0%-93.3% soil Cu had been successfully removed. A series of biological assays including soil microbial biomass carbon, basal soil respiration, soil urease activity, earthworm assays, and seed assays were used to evaluate their ecological risks. The results showed that the bioassay data from the treatment variants did not supposedly reflecting the decreased soil Cu concentrations after the electrokinetic treatment, but were highly correlated with some soil physicochemical characteristics. It suggests that bioassays are necessary to assess the ecotoxicity of soil after electrokinetic treatment. - There has been a motivation towards using biological indicators for risk assessment of contaminated soil after electrokinetic remediation.

  10. Application of bioassays to evaluate a copper contaminated soil before and after a pilot-scale electrokinetic remediation

    International Nuclear Information System (INIS)

    Wang Quanying; Zhou Dongmei; Cang Long; Sun Tianran

    2009-01-01

    Remediation programmes are considered to be complete when human risk-based criteria are met. However, these targets are often unsatisfied with the ecological parameters that may be important with regard to future soil use. Five soil subsamples, collecting along a pilot-scale soil column after electrokinetic treatment, were studied, from which about 42.0%-93.3% soil Cu had been successfully removed. A series of biological assays including soil microbial biomass carbon, basal soil respiration, soil urease activity, earthworm assays, and seed assays were used to evaluate their ecological risks. The results showed that the bioassay data from the treatment variants did not supposedly reflecting the decreased soil Cu concentrations after the electrokinetic treatment, but were highly correlated with some soil physicochemical characteristics. It suggests that bioassays are necessary to assess the ecotoxicity of soil after electrokinetic treatment. - There has been a motivation towards using biological indicators for risk assessment of contaminated soil after electrokinetic remediation

  11. REMEDIATION OF SOILS CONTAMINATED WITH MOTOR OIL BY HIGHLY BIODEGRADABLE SURFACTANTS

    Directory of Open Access Journals (Sweden)

    Ignacio Moya-Ramírez

    2014-06-01

    Full Text Available The remediation of a sandy soil contaminated with motor oil was studied by applying two different washing procedures: one discontinuous and the other continuous. In addition the capacity of three highly biodegradable surfactants, two synthetic (Glucopon 600 and Findet 1214N/23 and a biosurfactant from Bacillus subtilis, to enhance oil removal was tested. The results obtained with the continuous procedure were much better than those achieved with the discontinuous one, even in experiments conducted with distilled water. Both the addition of surfactants and the rise in temperature significantly increased the removal of the pollutant in experiments conducted with the discontinuous procedure, but the biosurfactant showed a higher capacity for soil remediation than the synthetic surfactants at concentrations close to its CMC. Conversely, when the continuous method was used, surfactant concentration seems to have a lower effect on motor oil removal, at least below the CMC.

  12. In situ remediation of Jet A in soil and ground water by high vacuum, dual phase extraction

    International Nuclear Information System (INIS)

    Kirshner, M.; Pressly, N.C.; Roth, R.J.

    1996-01-01

    This report summarizes the initial results of subsurface remediation at Terminal 1, Kennedy International Airport, to remediate soil and ground water contaminated with Jet A fuel. The project was driven and constrained by the construction schedule of a major new terminal at the facility. The remediation system used a combination of ground water pumping, air injection, and soil vapor extraction. In the first five months of operation, the combined processes of dewatering, volatilization, and biodegradation removed a total of 36,689 pounds of total volatile and semivolatile organic jet fuel hydrocarbons from subsurface soil and ground water. The results of this case study have shown that 62% of the removal resulted from biodegradation, 27% occurred as a result of liquid removal, and 11% resulted from the extraction of volatile organic compounds (VOCs)

  13. Effects and mechanisms of biochar-microbe interactions in soil improvement and pollution remediation: A review.

    Science.gov (United States)

    Zhu, Xiaomin; Chen, Baoliang; Zhu, Lizhong; Xing, Baoshan

    2017-08-01

    Biochars have attracted tremendous attention due to their effects on soil improvement; they enhance carbon storage, soil fertility and quality, and contaminant (organic and heavy metal) immobilization and transformation. These effects could be achieved by modifying soil microbial habitats and (or) directly influencing microbial metabolisms, which together induce changes in microbial activity and microbial community structures. This review links microbial responses, including microbial activity, community structures and soil enzyme activities, with changes in soil properties caused by biochars. In particular, we summarized possible mechanisms that are involved in the effects that biochar-microbe interactions have on soil carbon sequestration and pollution remediation. Special attention has been paid to biochar effects on the formation and protection of soil aggregates, biochar adsorption of contaminants, biochar-mediated transformation of soil contaminants by microorganisms, and biochar-facilitated electron transfer between microbial cells and contaminants and soil organic matter. Certain reactive organic compounds and heavy metals in biochar may induce toxicity to soil microorganisms. Adsorption and hydrolysis of signaling molecules by biochar interrupts microbial interspecific communications, potentially altering soil microbial community structures. Further research is urged to verify the proposed mechanisms involved in biochar-microbiota interactions for soil remediation and improvement. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Remediation in Situ of Hydrocarbons by Combined Treatment in a Contaminated Alluvial Soil due to an Accidental Spill of LNAPL

    Directory of Open Access Journals (Sweden)

    Ettore Trulli

    2016-10-01

    Full Text Available Soil contamination represents an environmental issue which has become extremely important in the last decades due to the diffusion of industrial activities. Accidents during transport of dangerous materials and fuels may cause severe pollution. The present paper describes the criteria of the actions which were operated to remediate the potential risk and observed negative effects on groundwater and soil originating from an accidental spill of diesel fuel from a tank truck. With the aim to evaluate the quality of the involved environmental matrices in the “emergency” phase, in the following “safety” operation and during the remediation action, a specific survey on hydrocarbons, light and heavy, was carried out in the sand deposits soil. Elaboration of collected data allows us to observe the movement of pollutants in the unsaturated soil. The remediation action was finalized to improve the groundwater and soil quality. The former was treated by a so called “pump and treat” system coupled with air sparging. A train of three different technologies was applied to the unsaturated soil in a sequential process: soil vapour extraction, bioventing and enhanced bioremediation. Results showed that the application of sequential remediation treatments allowed us to obtain a state of quality in unsaturated soil and groundwater as required by Italian law.

  15. Combined Effects of Biochar and Fertilizer on Cadmium Contaminated Soil Remediation

    OpenAIRE

    WANG Qi-kai; GUO Wen-juan; SUN Guo-hong; LIN Da-song; XU Ying-ming; LIU Jing-ru; YU Shi-lei

    2015-01-01

    The field experiment was employed to study on the combined effects of biochar and chicken manure and N, P and K compound chemical fertilizer on cadmium contaminated soil remediation, and the immobilization mechanism was elucidated through fractionation of cadmium in the tested soil. Results showed that the addition of these ammendments could significantly reduce the edible Cd accumulation in Lactuca sativa L., decreased from 32.6% to 54.8% compared with the control. The application of these a...

  16. Comparative review of techniques used for in situ remediation of contaminated soils

    International Nuclear Information System (INIS)

    Escusol Tomey, M.; Rodriguez Abad, R.

    2014-01-01

    Soil pollution may influence the geotechnical parameters of the soil itself, properties such as solid particle density or water within its pores. It may also vary its friction angle, modify its structure and texture, or change the properties of its constitutive minerals due to the inclusion of polluting components. For these reasons, soil decontamination is an important factor to consider in geotechnics. This work focuses on those soil decontamination techniques carried out in situ, since they allow to eliminate soil pollutants in a less invasive way than confinement, containment or ex situ remediation techniques, causing a minor soil alteration and, therefore, affecting less to its mechanical properties. These factors should be taken into account when carrying out a geotechnical performance on a previously decontaminated soil. (Author)

  17. Remediation of explosive-polluted soil in slurry phase by aerobic biostimulation

    International Nuclear Information System (INIS)

    Xin, Baoping; Shen, Mengyue; Aslam, Hina; Wu, Feng

    2013-01-01

    There is a great volume of polluted soil by 2,4,6-trinitrotoluene (TNT) manufacturing wastewater containing dozen of nitrocompounds in China. In this study, biostimulation was used for remediating the explosive-polluted soil in aerobic bioslurry by monitoring the removal of total organic carbon (TOC). The results showed that the pulp density had almost no effect on TOC removal; whereas the acetone addition evidently improved remediation efficiency of the polluted soil by intrinsic microorganism, and the TOC removal increased from 25% to 38.4% when dose of acetone increased from 0% to 4% (v/v). The maximum TOC removal of 49.1% was achieved through further adjusting pH at 9.0 and temperature at 30 °C. The second order reaction fits well removal dynamics of TOC under the optimum conditions. With the average conditions, liquid phase TOC decreased from 3404 to 3144 mg/L and solid phase TOC dropped from 1022 to 104 mg/L, leading to toxicity decline by 35%; the optimum condition witnessed 48.9% of TOC removal from 4500 to 2300 mg/L in liquid phase, causing toxicity drop by 62%.

  18. Remediation of soils, sediments and sludges by extraction with organic solvents

    NARCIS (Netherlands)

    Noordkamp, E.R.

    1999-01-01

    Remediation of contaminated soils, sediments and sludges by extraction with organic solvents is still in the initial stages of development. So far hardly any scientific research has been carried out into this approach. Therefore, the main objective of the present investigation was to study

  19. When is a soil remediated? Comparison of biopiled and windrowed soils contaminated with bunker-fuel in a full-scale trial.

    Science.gov (United States)

    Coulon, Frédéric; Al Awadi, Mohammed; Cowie, William; Mardlin, David; Pollard, Simon; Cunningham, Colin; Risdon, Graeme; Arthur, Paul; Semple, Kirk T; Paton, Graeme I

    2010-10-01

    A six month field scale study was carried out to compare windrow turning and biopile techniques for the remediation of soil contaminated with bunker C fuel oil. End-point clean-up targets were defined by human risk assessment and ecotoxicological hazard assessment approaches. Replicate windrows and biopiles were amended with either nutrients and inocula, nutrients alone or no amendment. In addition to fractionated hydrocarbon analysis, culturable microbial characterisation and soil ecotoxicological assays were performed. This particular soil, heavy in texture and historically contaminated with bunker fuel was more effectively remediated by windrowing, but coarser textures may be more amendable to biopiling. This trial reveals the benefit of developing risk and hazard based approaches in defining end-point bioremediation of heavy hydrocarbons when engineered biopile or windrow are proposed as treatment option. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  20. Remediation of soil co-contaminated with petroleum and heavy metals by the integration of electrokinetics and biostimulation.

    Science.gov (United States)

    Dong, Zhi-Yong; Huang, Wen-Hui; Xing, Ding-Feng; Zhang, Hong-Feng

    2013-09-15

    Successful remediation of soil co-contaminated with high levels of organics and heavy metals is a challenging task, because that metal pollutants in soil can partially or completely suppress normal heterotrophic microbial activity and thus hamper biodegradation of organics. In this study, the benefits of integrating electrokinetic (EK) remediation with biodegradation for decontaminating soil co-contaminated with crude oil and Pb were evaluated in laboratory-scale experiments lasting for 30 days. The treated soil contained 12,500 mg/kg of total petroleum hydrocarbons (TPH) and 450 mg/kg Pb. The amendments of EDTA and Tween 80, together with a regular refreshing of electrolyte showed the best performance to remediate this contaminated soil. An important function of EDTA-enhanced EK treatment was to eliminate heavy metal toxicity from the soil, thus activating microbial degradation of oil. Although Tween 80 reduced current, it could serve as a second substrate for enhancing microbial growth and biodegradation. It was found that oil biodegradation degree and microbial numbers increased toward the anode and cathode. Microbial metabolism was found to be beneficial to metal release from the soil matrix. Under the optimum conditions, the soil Pb and TPH removal percentages after 30 days of running reached 81.7% and 88.3%, respectively. After treatment, both the residual soil Pb and TPH concentrations met the requirement of the Chinese soil environmental quality standards. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Comparative study of remediation of Cr(VI)-contaminated soil using electrokinetics combined with bioremediation.

    Science.gov (United States)

    He, Jiaying; He, Chiquan; Chen, Xueping; Liang, Xia; Huang, Tongli; Yang, Xuecheng; Shang, Hai

    2018-06-01

    The purpose of this research is to design a new bioremediation-electrokinetic (Bio-EK) remediation process to increase treatment efficiency of chromium contamination in soil. Upon residual chromium analysis, it is shown that traditional electrokinetic-PRB system (control) does not have high efficiency (80.26%) to remove Cr(VI). Bio-electrokinetics of exogenous add with reduction bacteria Microbacterium sp. Y2 and electrokinetics can enhance treatment efficiency Cr(VI) to 90.67% after 8 days' remediation. To optimize the overall performance, integrated bio-electrokinetics were designed by synergy with 200 g humic substances (HS) into the systems. According to our results, Cr(VI) (98.33%) was effectively removed via electrokinetics. Moreover, bacteria and humic substances are natural, sustainable, and economical enhancement agents. The research results indicated that the use of integrated bio-electrokinetics is an effective method to remediate chromium-contaminated soils.

  2. Innovative approaches for the remediation of arsenic and mercury pollution via soil washing

    International Nuclear Information System (INIS)

    Sierra, C.; Gonzalez-Coto, F.; Villa, R.; Menendez-Aguado, J. M.; Gallego, J. R.

    2009-01-01

    Soil washing techniques are ex situ remediation procedures to remove contaminants concentrating them into a minor volume through particle size separation, gravity separation, and attrition scrubbing; with or without the utilization of chemical additives. Systems incorporating these removal techniques offer possibilities for application to soils contaminated with a wide variety of heavy metal, radionuclides, and organic contaminants. (Author)

  3. ERC hazard classification matrices for above ground structures and groundwater and soil remediation activities

    International Nuclear Information System (INIS)

    Curry, L.R.

    1997-01-01

    This document provides the status of the preliminary hazard classification (PHC) process for the Environmental Restoration Contractor (ERC) above ground structures and groundwater and soil remediation activities currently underway for planned for fiscal year (FY) 1997. This classification process is based on current US Department of Energy (DOE), Richland Operations Office (RL) guidance for the classification of facilities and activities containing radionuclide and nonradiological hazardous material inventories. The above ground structures presented in the matrices were drawn from the Bechtel Hanford, Inc. (BHI) Decontamination and Decommissioning (D and D) Project Facility List (DOE 1996), which identifies the facilities in the RL-Environmental Restoration baseline contract in 1997. This document contains the following two appendices: (1) Appendix A, which consists of a matrix identifying PHC documents that have been issued for BHI's above ground structures and groundwater and soil remediation activities underway or planned for FY 1997, and (2) Appendix B, which consists of a matrix showing anticipated PHCs for above ground structures, and groundwater and soil remediation activities underway or planned for FY 1997. Appendix B also shows the schedule for finalization of PHCs for above ground structures with an anticipated classification of Nuclear

  4. Investigations involving oxidation-reduction (REDOX) pretreatment in conjunction with biological remediation of contaminated soils

    International Nuclear Information System (INIS)

    Montemagno, C.D.; Peters, R.W.; Tyree, A.

    1991-01-01

    Oxidation-reduction (REDOX) reactions are among the most important reactions involved in the environmental engineering field. Oxidation is a reaction in which the oxidation state of the treated compound is increased, i.e., the material loses electrons. Reduction involves the addition of a chemical (reducing) agent which lowers the oxidation state of a substance, i.e., the material gains electrons. Both processes of oxidation and reduction occur together. All REDOX reactions are thermodynamically based. There are a number of oxidizing agents which have been reported in the technical literature for treatment of refractory organic compounds. Common oxidizing agents include: hydrogen peroxide, ozone, ultraviolet (UV) irradiation, and combinations thereof, such as UV/ozone and UV/peroxide. A gradient of REDOX reactions is possible, depending on such factors as the oxidation-reduction reaction conditions, the availability of electron donors and acceptors, and the nature of the organic compounds involved. A review of the technical literature revealed that the majority of the oxidation-reduction applications have been in the areas of wastewater treatment and groundwater remediation, with very little attention devoted to the potential of using REDOX technologies for remediation of hydrocarbon contaminated soils. In this particular study, feasibility studies were performed on gasoline- contaminated soil. These studies focused on three major phases: 1) containment of the contamination by addition of tailoring agents to the soil, 2) biological remediation either performed in situ or on-site (using a slurry reactor system), and 3) pretreatment of the contaminated soils using REDOX systems, prior to biological remediation. This particular paper focuses on the third phase of the project, aimed at ''softening'' the refractory organics resulting in the formation of organic compounds which are more amenable to biological degradation. This paper focuses its attention on the use of

  5. Investigations involving oxidation-reduction (REDOX) pretreatment in conjunction with biological remediation of contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Montemagno, C. D. [Argonne National Laboratory, Argonne, IL (United States); Peters, R. W.; Tyree, A.

    1991-07-01

    Oxidation-reduction (REDOX) reactions are among the most important reactions involved in the environmental engineering field. Oxidation is a reaction in which the oxidation state of the treated compound is increased, i.e., the material loses electrons. Reduction involves the addition of a chemical (reducing) agent which lowers the oxidation state of a substance, i.e., the material gains electrons. Both processes of oxidation and reduction occur together. All REDOX reactions are thermodynamically based. There are a number of oxidizing agents which have been reported in the technical literature for treatment of refractory organic compounds. Common oxidizing agents include: hydrogen peroxide, ozone, ultraviolet (UV) irradiation, and combinations thereof, such as UV/ozone and UV/peroxide. A gradient of REDOX reactions is possible, depending on such factors as the oxidation-reduction reaction conditions, the availability of electron donors and acceptors, and the nature of the organic compounds involved. A review of the technical literature revealed that the majority of the oxidation-reduction applications have been in the areas of wastewater treatment and groundwater remediation, with very little attention devoted to the potential of using REDOX technologies for remediation of hydrocarbon contaminated soils. In this particular study, feasibility studies were performed on gasoline- contaminated soil. These studies focused on three major phases: 1) containment of the contamination by addition of tailoring agents to the soil, 2) biological remediation either performed in situ or on-site (using a slurry reactor system), and 3) pretreatment of the contaminated soils using REDOX systems, prior to biological remediation. This particular paper focuses on the third phase of the project, aimed at ''softening'' the refractory organics resulting in the formation of organic compounds which are more amenable to biological degradation. This paper focuses its attention on the use of

  6. Sampling errors associated with soil composites used to estimate mean Ra-226 concentrations at an UMTRA remedial-action site

    International Nuclear Information System (INIS)

    Gilbert, R.O.; Baker, K.R.; Nelson, R.A.; Miller, R.H.; Miller, M.L.

    1987-07-01

    The decision whether to take additional remedial action (removal of soil) from regions contaminated by uranium mill tailings involves collecting 20 plugs of soil from each 10-m by 10-m plot in the region and analyzing a 500-g portion of the mixed soil for 226 Ra. A soil sampling study was conducted in the windblown mill-tailings flood plain area at Shiprock, New Mexico, to evaluate whether reducing the number of soil plugs to 9 would have any appreciable impact on remedial-action decisions. The results of the Shiprock study are described and used in this paper to develop a simple model of the standard deviation of 226 Ra measurements on composite samples formed from 21 or fewer plugs. This model is used to predict as a function of the number of soil plugs per composite, the percent accuracy with which the mean 226 Ra concentration in surface soil can be estimated, and the probability of making incorrect remedial action decisions on the basis of statistical tests. 8 refs., 15 figs., 9 tabs

  7. [Mixture Leaching Remediation Technology of Arsenic Contaminated Soil].

    Science.gov (United States)

    Chen, Xun-feng; Li, Xiao-ming; Chen, Can; Yang, Qi; Deng, Lin-jing; Xie, Wei-qiang; Zhong, Yui; Huang, Bin; Yang, Wei-qiang; Zhang, Zhi-bei

    2016-03-15

    Soil contamination of arsenic pollution has become a severely environmental issue, while soil leaching is an efficient method for remediation of arsenic-contaminated soil. In this study, batch tests were primarily conducted to select optimal mixture leaching combination. Firstly, five conventional reagents were selected and combined with each other. Secondly, the fractions were analyzed before and after the tests. Finally, to explore the feasibility of mixed leaching, three soils with different arsenic pollution levels were used to compare the leaching effect. Comparing with one-step washing, the two-step sequential washing with different reagents increased the arsenic removal efficiency. These results showed that the mixture of 4 h 0.5 mol · L⁻¹ NaOH + 4 h 0.1 mol · L⁻¹ EDTA was found to be practicable, which could enhance the removal rate of arsenic from 66.67% to 91.83%, and the concentration of arsenic in soil was decreased from 186 mg · kg⁻¹ to 15.2 mg · kg⁻¹. Furthermore, the results indicated that the distribution of fractions of arsenic in soil changed apparently after mixture leaching. Leaching process could significantly reduce the available contents of arsenic in soil. Moreover, the mixture of 0.5 mol · L⁻¹ NaOH + 0.1 mol L⁻¹ EDTA could well decrease the arsenic concentration in aluminum-type soils, while the mixture of 0.5 mol · L⁻¹ OX + 0.5 mol · L⁻¹ NaOH could well decrease the arsenic concentration in iron-type soils.

  8. Differents remediation methodos for lead, chromium and cadmium contaminated soils

    International Nuclear Information System (INIS)

    Trelles, G; Pochintesta, L; Ehrlich, S.

    2008-01-01

    The usage of phosphates in the remediation of plots contaminated with heavy metals appears to be a good strategy to lessen the danger of these metals. This study analyses the effect of the mobilization of: Lead, chromium and cadmium by utilizing diverse forms of phosphates in contaminated soils of three different origins with ph modification and without it

  9. Technical Evaluation of Soil Remediation Alternatives at the Building 812 Operable Unit, Lawrence Livermore National Laboratory Site 300

    International Nuclear Information System (INIS)

    Eddy-Dilek, C.; Miles, D.; Abitz, R.

    2009-01-01

    The Department of Energy Livermore Site Office requested a technical review of remedial alternatives proposed for the Building 812 Operable Unit, Site 300 at the Lawrence Livermore National Laboratory. The team visited the site and reviewed the alternatives proposed for soil remediation in the draft RI/FS and made the following observations and recommendations. Based on the current information available for the site, the team did not identify a single technology that would be cost effective and/or ecologically sound to remediate DU contamination at Building 812 to current remedial goals. Soil washing is not a viable alternative and should not be considered at the site unless final remediation levels can be negotiated to significantly higher levels. This recommendation is based on the results of soil washing treatability studies at Fernald and Ashtabula that suggest that the technology would only be effective to address final remediation levels higher than 50 pCi/g. The technical review team identified four areas of technical uncertainty that should be resolved before the final selection of a preferred remedial strategy is made. Areas of significant technical uncertainty that should be addressed include: (1) Better delineation of the spatial distribution of surface contamination and the vertical distribution of subsurface contamination in the area of the firing table and associated alluvial deposits; (2) Chemical and physical characterization of residual depleted uranium (DU) at the site; (3) Determination of actual contaminant concentrations in air particulates to support risk modeling; and (4) More realistic estimation of cost for remedial alternatives, including soil washing, that were derived primarily from vendor estimates. Instead of conducting the planned soil washing treatability study, the team recommends that the site consider a new phased approach that combines additional characterization approaches and technologies to address the technical uncertainty in

  10. TECHNICAL EVALUATION OF SOIL REMEDIATION ALTERNATIVES AT THE BUILDING 812 OPERABLE UNIT, LAWRENCE LIVERMORE NATIONAL LABORATORY SITE 300

    Energy Technology Data Exchange (ETDEWEB)

    Eddy-Dilek, C.; Miles, D.; Abitz, R.

    2009-08-14

    The Department of Energy Livermore Site Office requested a technical review of remedial alternatives proposed for the Building 812 Operable Unit, Site 300 at the Lawrence Livermore National Laboratory. The team visited the site and reviewed the alternatives proposed for soil remediation in the draft RI/FS and made the following observations and recommendations. Based on the current information available for the site, the team did not identify a single technology that would be cost effective and/or ecologically sound to remediate DU contamination at Building 812 to current remedial goals. Soil washing is not a viable alternative and should not be considered at the site unless final remediation levels can be negotiated to significantly higher levels. This recommendation is based on the results of soil washing treatability studies at Fernald and Ashtabula that suggest that the technology would only be effective to address final remediation levels higher than 50 pCi/g. The technical review team identified four areas of technical uncertainty that should be resolved before the final selection of a preferred remedial strategy is made. Areas of significant technical uncertainty that should be addressed include: (1) Better delineation of the spatial distribution of surface contamination and the vertical distribution of subsurface contamination in the area of the firing table and associated alluvial deposits; (2) Chemical and physical characterization of residual depleted uranium (DU) at the site; (3) Determination of actual contaminant concentrations in air particulates to support risk modeling; and (4) More realistic estimation of cost for remedial alternatives, including soil washing, that were derived primarily from vendor estimates. Instead of conducting the planned soil washing treatability study, the team recommends that the site consider a new phased approach that combines additional characterization approaches and technologies to address the technical uncertainty in

  11. Large-scale sulfolane-impacted soil remediation at a gas plant

    Energy Technology Data Exchange (ETDEWEB)

    Lavoie, G.; Rockwell, K. [Biogenie Inc., Calgary, AB (Canada)

    2006-07-01

    A large-scale sulfolane-impacted soil remediation project at a gas plant in central Alberta was discussed. The plant was operational from the 1960s to present and the former operation involved the Sulfinol process which resulted in groundwater contamination. In 2005, the client wanted to address the sources area. The Sulfinol process has been used since the 1960s to remove hydrogen sulfide and other corrosive gases from natural gas streams. Sulfinol uses sulfolane and diisopropanolamine. Sulfolane is toxic, non-volatile, and water soluble. The presentation also addressed the remediation objectives and an additional site assessment that was conducted to better delineate the sulfolane and sulphur plume, as well as metals. The findings of the ESA and site specific challenges were presented. These challenges included: plant operation concerns; numerous overhead, surface, and underground structures; large volume of impacted material, limited space available on site; several types of contaminants; and time required to perform the overall work. Next, the sulfolane remediation strategy was discussed including advantages and results of the investigation. Last, the results of the project were presented. It was found that there were no recordable safety incidents and that all remedial objectives were achieved. tabs., figs.

  12. A critical review of ferrate(VI)-based remediation of soil and groundwater.

    Science.gov (United States)

    Rai, Prabhat Kumar; Lee, Jechan; Kailasa, Suresh Kumar; Kwon, Eilhann E; Tsang, Yiu Fai; Ok, Yong Sik; Kim, Ki-Hyun

    2018-01-01

    Over the past few decades, diverse chemicals and materials such as mono- and bimetallic nanoparticles, metal oxides, and zeolites have been used for soil and groundwater remediation. Ferrate (Fe VI O 4 2- ) has been widely employed due to its high-valent iron (VI) oxo compound with high oxidation/reduction potentials. Ferrate has received attention for wide environmental applications including water purification and sewage sludge treatment. Ferrate provides great potential for diverse environmental applications without any environmental problems. Therefore, this paper provides comprehensive information on the recent progress on the use of (Fe VI O 4 2- ) as a green material for use in sustainable treatment processes, especially for soil and water remediation. We reviewed diverse synthesis recipes for ferrates (Fe VI O 4 2- ) and their associated physicochemical properties as oxidants, coagulants, and disinfectants for the elimination of a diverse range of chemical and biological species from water/wastewater samples. A summary of the eco-sustainable performance of ferrate(VI) in water remediation is also provided and the future of ferrate(VI) is discussed in this review. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Lead immobilization in thermally remediated soils and igneous rocks

    International Nuclear Information System (INIS)

    Hickmott, D.D.; Carey, J.W.; Stimac, J.; Larocque, A.; Abell, R.; Gauerke, E.; Eppler, A.

    1997-01-01

    This is the final report for a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The principal goal of this project was to investigate the speciation of lead in the environment at LANL and to determine the feasibility of using thermal remediation methods to immobilize lead in the environment. Lead occurs as pyromorphite [Pb(PO 4 ) 3 (Cl, OH)], cerussite (PbCO 3 ) and galena (PbS) in vapor-phase-altered Bandelier Tuff samples. LANL soils primarily contain cerussite and PbO. Thermal remediation experiments at high temperatures (up to 400 C) suggest that thermal immobilization of highly-reactive Pb compounds in the environment may be feasible, but that this technique is not optimal for more refractory lead phases such as cerussite and PbO

  14. Remediation and reclamation of soils heavily contaminated with toxic metals as a substrate for greening with ornamental plants and grasses.

    Science.gov (United States)

    Jelusic, Masa; Lestan, Domen

    2015-11-01

    Soils highly contaminated with toxic metals are currently treated as waste despite their potential inherent fertility. We applied EDTA washing technology featuring chelant and process water recovery for remediation of soil with 4037, 2527, and 26 mg kg(-1) of Pb, Zn and Cd, respectively in a pilot scale. A high EDTA dose (120 mmol kg(-1) of soil) removed 70%, 15%, and 58% of Pb, Zn, and Cd, respectively, and reduced human oral bioaccessibility of Pb below the limit of quantification and that of Zn and Cd 3.4 and 3.2 times. In a lysimeters experiment, the contaminated and remediated soils were laid into two garden beds (4×1×0.15 m) equipped with lysimeters, and subjected to cultivation of ornamental plants: Impatiens walleriana, Tagetes erecta, Pelargonium×peltatum, and Verbena×hybrida and grasses: Dactylis glomerata, Lolium multiflorum, and Festuca pratensis. Plants grown on remediated soil demonstrated the same or greater biomass yield and reduced the uptake of Pb, Zn and Cd up to 10, 2.5 and 9.5 times, respectively, compared to plants cultivated on the original soil. The results suggest that EDTA remediation produced soil suitable for greening. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Phytoextraction and estimating optimal time for remediation of Cd-contaminated soils by Spinach

    OpenAIRE

    Somayyeh Eisazadeh Lazarjan; safoora asadi kapourchal; Mehdi Homaee

    2016-01-01

    The so-called phytoextraction in which hyperaccumulator plants are used to remediate the contaminated soils is proven to be an efficient method. The objective of this study was to investigate the capability of Spinach for phytoremediation of cadmium from Cd-contaminated soils and determine the efficiency extent of spinach for phytoremediation. For this purpose, a randomized block experimental design whit five treatments including 0, 15, 30, 60 and 120 mg Cd/ kg soil and three replications was...

  16. The sequential use of washing and an electrochemical reduction process for the remediation of lead-contaminated soils.

    Science.gov (United States)

    Demir, Aydeniz; Köleli, Nurcan

    2013-01-01

    A two-step method for the remediation of three different types of lead (Pb)-contaminated soil was evaluated. The first step included soil washing with ethylenediaminetetraacetic acid (EDTA) to remove Pb from soils. The washing experiments were performed with 0.05 M Na2EDTA at 1:10 soil to liquid ratio. Following the washing, Pb removal efficiency from soils ranged within 50-70%. After the soil washing process, Pb2+ ions in the washing solution were reduced electrochemically in a fixed-bed reactor. Lead removal efficiency with the electrochemical reduction at -2.0 V potential ranged within 57-76%. The overall results indicate that this two-step method is an environmentally-friendly and effective technology to remediate Pb-contaminated soils, as well as Pb-contaminated wastewater treatment due to the transformation of toxic Pb2+ ions into a non-hazardous metallic form (Pb(0)).

  17. Source zone remediation by ZVI-clay soil-mixing: Reduction of tetrachloroethene mass and mass discharge at a Danish DNAPL site

    DEFF Research Database (Denmark)

    Fjordbøge, Annika Sidelmann; Lange, Ida Vedel; Binning, Philip John

    2012-01-01

    The presence of chlorinated solvent source zones in the subsurface pose a continuous threat to groundwater quality. The remediation of Dense Non-Aqueous Phase Liquid (DNAPL) sites is especially challenging and the development of innovative remediation technologies is needed. Zero-valent iron (ZVI......) technologies have proven effective for remediation of chlorinated compounds. ZVI-Clay soil-mixing is a new remediation technology, which combines abiotic degradation (via ZVI addition) and immobilization (via soil-mixing and clay addition), whereby a great potential for reduction of both contaminant mass....... The concentrations of chlorinated ethenes were monitored via soil sampling at the source zone and groundwater sampling at a control plane with multilevel samplers covering the entire contaminated plume down-gradient (3 m) of the source zone. The results showed a significant mass depletion of PCE (2-3 orders...

  18. Apatite ore mine tailings as an amendment for remediation of a lead-contaminated shooting range soil.

    Science.gov (United States)

    Venäläinen, Salla H

    2011-10-01

    This study investigated the use of tailings from apatite ore beneficiation in the remediation of a heavily contaminated shooting range soil. The tailings originating in Siilinjärvi carbonatite complex, Finland, consist of apatite residues accompanied by phlogopite and calcite. In a pot experiment, organic top layer of a boreal forest soil predisposed to pellet-derived lead (Pb) was amended with tailings of various particle-sizes (Ø>0.2mm, Øremediation technique at polluted sites. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Phytoextraction of arsenic-contaminated soil with Pteris vittata in Henan Province, China: comprehensive evaluation of remediation efficiency correcting for atmospheric depositions.

    Science.gov (United States)

    Lei, Mei; Wan, Xiaoming; Guo, Guanghui; Yang, Junxing; Chen, Tongbin

    2018-01-01

    Research on the appropriate method for evaluating phytoremediation efficiency is limited. A 2-year field experiment was conducted to investigate phytoremediation efficiency using the hyperaccumulator Pteris vittata on an arsenic (As)-contaminated site. The remediation efficiency was evaluated through the removal rate of As in soils and extraction rate of heavy metals in plants. After 2 years of remediation, the concentration of total As in soils decreased from 16.27 mg kg -1 in 2012 to 14.58 mg kg -1 in 2014. The total remediation efficiency of As was 10.39% in terms of the removal rate of heavy metals calculated for soils, whereas the remediation efficiency calculated from As uptake by P. vittata was 16.09%. Such a discrepancy aroused further consideration on the potential input of As. A large amount of As was brought in by atmospheric emissions, which possibly biased the calculation of remediation efficiency. In fact, considering also the atmospheric depositions of As, the corrected removal rate of As from soil was 16.57%. Therefore, the results of this work suggest that (i) when evaluating the phytoextraction efficiency, the whole input and output cycle of the element of interest in the targeted ecosystem must be considered, and (ii) P. vittata has the potential to be used to remediate As-contaminated soils in Henan Province, China.

  20. Biochemical parameters and bacterial species richness in soils contaminated by sludge-borne metals and remediated with inorganic soil amendments

    International Nuclear Information System (INIS)

    Mench, Michel; Renella, Giancarlo; Gelsomino, Antonio; Landi, Loretta; Nannipieri, Paolo

    2006-01-01

    The effectiveness of two amendments for the in situ remediation of a Cd- and Ni-contaminated soil in the Louis Fargue long-term field experiment was assessed. In April 1995, one replicate plot (S1) was amended with 5% w/w of beringite (B), a coal fly ash (treatment S1 + B), and a second plot with 1% w/w zerovalent-Fe iron grit (SS) (treatment S1+SS), with the aim of increasing metal sorption and attenuating metal impacts. Long-term responses of daily respiration rates, microbial biomass, bacterial species richness and the activities of key soil enzymes (acid and alkaline phosphatase, arylsulfatase, β-glucosidase, urease and protease activities) were studied in relation to soil metal extractability. Seven years after initial amendments, the labile fractions of Cd and Ni in both the S1 + B and S1 + SS soils were reduced to various extents depending on the metal and fractions considered. The soil microbial biomass and respiration rate were not affected by metal contamination and amendments in the S1 + B and S1 + SS soils, whereas the activity of different soil enzymes was restored. The SS treatment was more effective in reducing labile pools of Cd and Ni and led to a greater recovery of soil enzyme activities than the B treatment. Bacterial species richness in the S1 soil did not alter with either treatment. It was concluded that monitoring of the composition and activity of the soil microbial community is important in evaluating the effectiveness of soil remediation practices. - Amendments (coal fly ash, zerovalent-Fe iron grit), reduced labile fractions of Cd and Ni in contaminated soils and restored the activity of key soil hydrolases

  1. Solid/solution Cu fractionations/speciation of a Cu contaminated soil after pilot-scale electrokinetic remediation and their relationships with soil microbial and enzyme activities

    International Nuclear Information System (INIS)

    Wang Quanying; Zhou Dongmei; Cang Long; Li Lianzhen; Wang Peng

    2009-01-01

    The aim of this study was to investigate the detailed metal speciation/fractionations of a Cu contaminated soil before and after electrokinetic remediation as well as their relationships with the soil microbial and enzyme activities. Significant changes in the exchangeable and adsorbed-Cu fractionations occurred after electrokinetic treatment, while labile soil Cu in the solution had a tendency to decrease from the anode to the cathode, and the soil free Cu 2+ ions were mainly accumulated in the sections close to the cathode. The results of regression analyses revealed that both the soil Cu speciation in solution phase and the Cu fractionations in solid phase could play important roles in the changes of the soil microbial and enzyme activities. Our findings suggest that the bioavailability of soil heavy metals and their ecotoxicological effects on the soil biota before and after electroremediation can be better understood in terms of their chemical speciation and fractionations. - The assessment of the roles of soil solution speciation and solid-phase fractionations in metal bioavailability after electrokinetic remediation deserves close attention.

  2. Evaluation of the assimilation of As by vegetables in contaminated soils submitted to a remediation process

    Science.gov (United States)

    Pérez-Sirvent, Carmen; Martinez Sanchez, Maria Jose; Agudo, Ines; Belen Martinez, Lucia; Bech, Jaume

    2016-04-01

    A greenhouse trial was carried out to evaluate the assimilation of heavy metals by three types of plants (lettuce, onion and broccoli), different parts of which are destined for human and farm animals consumption (leaves, roots, fruits). The experiments were carried out to check the validity of the use of calcareous materials to recover soils contaminated with heavy metals. The aim of this work was to apply a technology for decontamination to ensure that As do not enter into the trophic chain at risky levels and analyze and to assess the risk pre and post operational of the different treatments proposed. The materials used was a soils to be remediated (mining soils) and the materials used for remediation were lime filler and Construction and Demolition Waste (CDW). The plants were cultivated in greenhouse with several types of soil. Five experiments were used, namely, Tc (contaminated soil), T1 (uncontaminated soil (blank soil)), T2 (50% T1 + 50% Tc), T3 (Tc + (25%) lime residues coming from quarries) and T4 (Tc + (25%) residues coming from demolition and construction activities). The entire project involves twenty experiments which were prepared from soils highly contaminated mixed with two types of calcareous materials. The total As content of the soils samples, rhizosphere and vegetable samples, were measured and the translocation factor (TF), which is defined as the ratio of metal concentration in the leaves or shoots to the roots, and the Bioconcentration factor (BCF), which is defined as the ratio of metal concentration in the roots to that in soil were calculated. The use of CDR is shown to be a suitable way for remediating soils contaminated by metals. The methodology permits a revalorization of CDW.

  3. Monitoring of Soil Remediation Process in the Metal Mining Area

    Science.gov (United States)

    Kim, Kyoung-Woong; Ko, Myoung-Soo; Han, Hyeop-jo; Lee, Sang-Ho; Na, So-Young

    2016-04-01

    Stabilization using proper additives is an effective soil remediation technique to reduce As mobility in soil. Several researches have reported that Fe-containing materials such as amorphous Fe-oxides, goethite and hematite were effective in As immobilization and therefore acid mine drainage sludge (AMDS) may be potential material for As immobilization. The AMDS is the by-product from electrochemical treatment of acid mine drainage and mainly contains Fe-oxide. The Chungyang area in Korea is located in the vicinity of the huge abandoned Au-Ag Gubong mine which was closed in the 1970s. Large amounts of mine tailings have been remained without proper treatment and the mobilization of mine tailings can be manly occurred during the summer heavy rainfall season. Soil contamination from this mobilization may become an urgent issue because it can cause the contamination of groundwater and crop plants in sequence. In order to reduce the mobilization of the mine tailings, the pilot scale study of in-situ stabilization using AMDS was applied after the batch and column experiments in the lab. For the monitoring of stabilization process, we used to determine the As concentration in crop plants grown on the field site but it is not easily applicable because of time and cost. Therefore, we may need simple monitoring technique to measure the mobility or leachability which can be comparable with As concentration in crop plants. We compared several extraction methods to suggest the representative single extraction method for the monitoring of soil stabilization efficiency. Several selected extraction methods were examined and Mehlich 3 extraction method using the mixture of NH4F, EDTA, NH4NO3, CH3COOH and HNO3 was selected as the best predictor of the leachability or mobility of As in the soil remediation process.

  4. The interactions of composting and biochar and their implications for soil amendment and pollution remediation: a review.

    Science.gov (United States)

    Wu, Haipeng; Lai, Cui; Zeng, Guangming; Liang, Jie; Chen, Jin; Xu, Jijun; Dai, Juan; Li, Xiaodong; Liu, Junfeng; Chen, Ming; Lu, Lunhui; Hu, Liang; Wan, Jia

    2017-09-01

    Compost and biochar, used for the remediation of soil, are seen as attractive waste management options for the increasing volume of organic wastes being produced. This paper reviews the interaction of biochar and composting and its implication for soil amendment and pollution remediation. The interaction of biochar and composting affect each other's properties. Biochar could change the physico-chemical properties, microorganisms, degradation, humification and gas emission of composting, such as the increase of nutrients, cation exchange capacity (CEC), organic matter and microbial activities. The composting could also change the physico-chemical properties and facial functional groups of biochar, such as the improvement of nutrients, CEC, functional groups and organic matter. These changes would potentially improve the efficiency of the biochar and composting for soil amendment and pollution remediation. Based on the above review, this paper also discusses the future research required in this field.

  5. Remediation of heavy metal(loid)s contaminated soils--to mobilize or to immobilize?

    Science.gov (United States)

    Bolan, Nanthi; Kunhikrishnan, Anitha; Thangarajan, Ramya; Kumpiene, Jurate; Park, Jinhee; Makino, Tomoyuki; Kirkham, Mary Beth; Scheckel, Kirk

    2014-02-15

    Unlike organic contaminants, metal(loid)s do not undergo microbial or chemical degradation and persist for a long time after their introduction. Bioavailability of metal(loid)s plays a vital role in the remediation of contaminated soils. In this review, the remediation of heavy metal(loid) contaminated soils through manipulating their bioavailability using a range of soil amendments will be presented. Mobilizing amendments such as chelating and desorbing agents increase the bioavailability and mobility of metal(loid)s. Immobilizing amendments such of precipitating agents and sorbent materials decrease the bioavailabilty and mobility of metal(loid)s. Mobilizing agents can be used to enhance the removal of heavy metal(loid)s though plant uptake and soil washing. Immobilizing agents can be used to reduce the transfer to metal(loid)s to food chain via plant uptake and leaching to groundwater. One of the major limitations of mobilizing technique is susceptibility to leaching of the mobilized heavy metal(loid)s in the absence of active plant uptake. Similarly, in the case of the immobilization technique the long-term stability of the immobilized heavy metal(loid)s needs to be monitored. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Evaluation of silkworm excrement and mushroom dreg for the remediation of multiple heavy metal/metalloid contaminated soil using pakchoi.

    Science.gov (United States)

    Wang, Ruigang; Guo, Junkang; Xu, Yingming; Ding, Yongzhen; Shen, Yue; Zheng, Xiangqun; Feng, Renwei

    2016-02-01

    The economical, environmental friendly and efficient materials to remediate the pollution with multiple heavy metals and metalloids are scarce. Silkworm excrement (SE) and mushroom dregs (MD) are two types of agricultural wastes, and they are widely used to improve the soil fertility in many regions of China. A pot experiment with sixteen treatments was set up to assess the possibility of using SE and MD to stabilize heavy metals and metalloids and reduce their uptake in pakchoi cultivated in slightly contaminated soils with arsenic (As), cadmium (Cd), lead (Pb) and zinc (Zn). The results showed that the single addition of SE obviously stimulated the growth of pakchoi, reduced the contents of all tested heavy metals and metalloids in the edible part of pakchoi and availability of Zn and Cd in soil. The single MD treatment showed an inferior ability to enhance the growth and reduce the contents of heavy metals and metalloids in the edible part of pakchoi. The combined utilization of SE and MD appeared not to show better effects than their individual treatment when using them to remediate this contaminated soil. Some potential mechanisms on the stimulation on pakchoi growth and decreasing the accumulation of heavy metals and metalloids in pakchoi subjected to SE were suggested, including: (1) enhancing soil pH to impact the availability of heavy metals and metalloids; (2) improve the fertility of soil; (3) sulfhydryl groups of organic materials in SE play a role in conjugating heavy metals and metalloids to affect their availability in soil; and (4) stimulating the growth of pakchoi so as to show a "dilution effect" of heavy metals and metalloids. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Use of in-situ Dual Vacuum Extraction trademark for remediation of soil and ground water

    International Nuclear Information System (INIS)

    Dodson, M.E.; Trowbridge, B.E.; Ott, D.

    1994-01-01

    Dual Vacuum Extraction trademark provides a rapid and cost-effective method of remediating soil and ground water contaminated with volatile organic compounds. The system involves the removal of both water and vapors through the same borehole by use of entrainment. This technology provides for the remediation of the vadose zone, capillary fringe, smear zone, and existing water table. The effectiveness of this technology is shown in a case study. A release from an underground storage tank was responsible for a hydrocarbon plume spreading over approximately 50,000 ft 2 . The release produced vadose-zone contamination in the silty and sandy clays from 10 to 30 ft below ground surface (bgs) with total petroleum hydrocarbon (TPH) concentrations up to 1,400 mg/kg. In addition, a layer of free-floating liquid hydrocarbon was present on a shallow aquifer located at 25 ft bgs in thicknesses ranging from 0.5 to 3.0 ft. An in-situ dual-extraction system was installed to remediate the soils and ground water to levels as required by the Los Angeles Regional Water Quality Control Board (RWQCB). The system operated 24 hr a day, with an operating efficiency of over 99%. After 196 days (28 weeks), over 17,000 lb of hydrocarbons had been extracted from the soils. Seven confirmatory soil borings in the area of highest initial hydrocarbon concentrations indicated that TPH and benzene, toluene, ethylbenzene, xylene (BTEX) concentrations had decreased over 99% from initial soil concentrations

  8. Assessing the potential of brachiaria decumbens as remediation agent for soil contaminated wit oil sludge

    International Nuclear Information System (INIS)

    Latiffah Norddin; Ahmad Nazrul Abd Wahid; Hazlina Abdullah; Abdul Razak Ruslan

    2005-01-01

    Bioremediation is a method of treatment of soil or water contaminated with toxic materials, involving the use of living organisms. Oil or petroleum sludge is a waste product of the petroleum refining industry, and is now accumulating at a fast rate at petroleum refinery sites in the country. Common components of oil sludge are mud and sand, containing toxic materials from hydrocarbons, heavy metals and radioactive elements from the seabed. In the present study, the oil sludge samples were obtained from barrels of the materials stored at the Radioactive Waste Treatment Centre, MINT. The samples were analysed of their compounds, elemental and radioactive contents. Trials on microbial degradation of the sludge materials were ongoing. This paper discusses the potential of a grass to remediate soils contaminated with petroleum sludge. Remediation of soils contaminated with organic compounds and heavy metals using plants, including grasses, including Vetiver, Lolium and Agrostis have been carried out in many countries. A greenhouse pot trial was conducted to assess the suitability of the pasture grass Brachiaria decumbens Stapf. and its mutant Brachiaria decumbens KLUANG Comel as a remediation agent for oil sludge contaminated soil. Samples of grasses and soils before planting, during growth stage and at end of experiment were analysed for the different toxicity. Although the grasses were promoted for use in pasture, and KLUANG Comel has good potential as an ornamental plant, too, their other potentials, including as phytoremediation agents need to be explored. (Author)

  9. The remediation of the lead-polluted garden soil by natural zeolite.

    Science.gov (United States)

    Li, Hua; Shi, Wei-yu; Shao, Hong-bo; Shao, Ming-an

    2009-09-30

    The current study investigated the remediation effect of lead-polluted garden soil by natural zeolite in terms of soil properties, Pb fraction of sequential extraction in soil and distribution of Pb in different parts of rape. Natural zeolite was added to artificially polluted garden soil to immobilize and limit the uptake of lead by rape through changing soil physical and chemical properties in the pot experiment under greenhouse conditions. Results indicated that the addition of natural zeolite could increase soil pH, CEC, content of soil organic matter and promote formation of soil aggregate. The application of zeolite decreased the available fraction of Pb in the garden soil by adjusting soil pH rather than CEC, and restrained the Pb uptake by rape. Data obtained suggested that the application of a dose of zeolite was adequate (>or=10 g kg(-1)) to reduce soluble lead significantly, even if lead pollution is severe in garden soil (>or=1000 mg kg(-1)). An appropriate dose of zeolite (20 g kg(-1)) could reduce the Pb concentration in the edible part (shoots) of rape up to 30% of Pb in the seriously polluted soil (2000 mg kg(-1)).

  10. Evaluation and determination of soil remediation schemes using a modified AHP model and its application in a contaminated coking plant.

    Science.gov (United States)

    Li, Xingang; Li, Jia; Sui, Hong; He, Lin; Cao, Xingtao; Li, Yonghong

    2018-07-05

    Soil remediation has been considered as one of the most difficult pollution treatment tasks due to its high complexity in contaminants, geological conditions, usage, urgency, etc. The diversity in remediation technologies further makes quick selection of suitable remediation schemes much tougher even the site investigation has been done. Herein, a sustainable decision support hierarchical model has been developed to select, evaluate and determine preferred soil remediation schemes comprehensively based on modified analytic hierarchy process (MAHP). This MAHP method combines competence model and the Grubbs criteria with the conventional AHP. It not only considers the competence differences among experts in group decision, but also adjusts the big deviation caused by different experts' preference through sample analysis. This conversion allows the final remediation decision more reasonable. In this model, different evaluation criteria, including economic effect, environmental effect and technological effect, are employed to evaluate the integrated performance of remediation schemes followed by a strict computation using above MAHP. To confirm the feasibility of this developed model, it has been tested by a benzene workshop contaminated site in Beijing coking plant. Beyond soil remediation, this MAHP model would also be applied in other fields referring to multi-criteria group decision making. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Citric acid facilitated thermal treatment: An innovative method for the remediation of mercury contaminated soil

    International Nuclear Information System (INIS)

    Ma, Fujun; Peng, Changsheng; Hou, Deyi; Wu, Bin; Zhang, Qian; Li, Fasheng; Gu, Qingbao

    2015-01-01

    Highlights: • Hg content was reduced to <1.5 mg/kg when treated at 400 °C with citric acid. • The treated soil retained most of its original soil physicochemical properties. • Proton provided by citric acid facilitates thermal removal of mercury. • This thermal treatment method is expected to reduce energy input by 35%. - Abstract: Thermal treatment is a promising technology for the remediation of mercury contaminated soils, but it often requires high energy input at heating temperatures above 600 °C, and the treated soil is not suitable for agricultural reuse. The present study developed a novel method for the thermal treatment of mercury contaminated soils with the facilitation of citric acid (CA). A CA/Hg molar ratio of 15 was adopted as the optimum dosage. The mercury concentration in soils was successfully reduced from 134 mg/kg to 1.1 mg/kg when treated at 400 °C for 60 min and the treated soil retained most of its original soil physiochemical properties. During the treatment process, CA was found to provide an acidic environment which enhanced the volatilization of mercury. This method is expected to reduce energy input by 35% comparing to the traditional thermal treatment method, and lead to agricultural soil reuse, thus providing a greener and more sustainable remediation method for treating mercury contaminated soil in future engineering applications.

  12. Citric acid facilitated thermal treatment: An innovative method for the remediation of mercury contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Fujun [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Peng, Changsheng [The Key Lab of Marine Environmental Science and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); Hou, Deyi [Geotechnical and Environmental Research Group, Department of Engineering, University of Cambridge, Cambridge CB2 1PZ (United Kingdom); Wu, Bin; Zhang, Qian; Li, Fasheng [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Gu, Qingbao, E-mail: guqb@craes.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China)

    2015-12-30

    Highlights: • Hg content was reduced to <1.5 mg/kg when treated at 400 °C with citric acid. • The treated soil retained most of its original soil physicochemical properties. • Proton provided by citric acid facilitates thermal removal of mercury. • This thermal treatment method is expected to reduce energy input by 35%. - Abstract: Thermal treatment is a promising technology for the remediation of mercury contaminated soils, but it often requires high energy input at heating temperatures above 600 °C, and the treated soil is not suitable for agricultural reuse. The present study developed a novel method for the thermal treatment of mercury contaminated soils with the facilitation of citric acid (CA). A CA/Hg molar ratio of 15 was adopted as the optimum dosage. The mercury concentration in soils was successfully reduced from 134 mg/kg to 1.1 mg/kg when treated at 400 °C for 60 min and the treated soil retained most of its original soil physiochemical properties. During the treatment process, CA was found to provide an acidic environment which enhanced the volatilization of mercury. This method is expected to reduce energy input by 35% comparing to the traditional thermal treatment method, and lead to agricultural soil reuse, thus providing a greener and more sustainable remediation method for treating mercury contaminated soil in future engineering applications.

  13. Soil bioindicators as a usefull tools for land management and spatial planning processes: a case-study of prioritization of contaminated soil remediation

    Science.gov (United States)

    Grand, Cécile; Pauget, Benjamin; Villenave, Cécile; Le Guédard, Marina; Piron, Denis; Nau, Jean-François; Pérès, Guénola

    2017-04-01

    When setting up new land management, contaminated site remediation or soil use change are sometimes necessary to ensure soil quality and the restoration of the ecosystem services. The biological characterization of the soil can be used as complementary information to chemical data in order to better define the conditions for operating. Then, in the context of urban areas, elements on the soil biological quality can be taken into consideration to guide the land development. To assess this "biological state of soil health", some biological tools, called bioindicators, could provide comprehensive information to understand and predict the functioning of the soil ecosystem. In this context, a city of 200 thousand inhabitants has decided to integrate soil bioindicators in their soil diagnostic for their soil urban management. This city had to elaborate a spatial soil management in urban areas which presented soil contamination linked to a complex industrial history associated with bad uses of gardens not always safe for the environment. The project will lead to establish a Natural Urban Park (PNU) in order to develop recreational and leisure activities in a quality environment. In order to complete the knowledge of soil contamination and to assess the transfer of contaminants to the terrestrial ecosystem, a biological characterization of soils located in different areas was carried out using six bioindicators: bioindicators of accumulation which allowed to evaluate the transfers of soil contaminants towards the first 2 steps of a trophic chain (plants and soil fauna, e.g. snails), bioindicators of effects (Omega 3 index was used to assess the effects of soil contamination and to measure their impact on plants), bioindicators of soil functioning (measurement of microbial biomass, nematodes and earthworm community) ; the interest of these last bioindicators is that they also act on the functioning of ecosystems as on the dynamics of organic matter (mineralization) but also

  14. Coordinating bifurcated remediation of soil and groundwater at sites containing multiple operable units

    International Nuclear Information System (INIS)

    Laney, D.F.

    1996-01-01

    On larger and/or more complex sites, remediation of soil and groundwater is sometimes bifurcated. This presents some unique advantages with respect to expedited cleanup of one medium, however, it requires skillful planning and significant forethought to ensure that initial remediation efforts do not preclude some long-term options, and/or unduly influence the subsequent selection of a technology for the other operable units and/or media. this paper examines how the decision to bifurcate should be approached, the various methods of bifurcation, the advantages and disadvantages of bifurcation, and the best methods to build flexibility into the design of initial remediation systems so as to allow for consideration of a fuller range of options for remediation of other operable units and/or media at a later time. Pollutants of concern include: metals; petroleum hydrocarbons; and chlorinated solvents

  15. Modelling cadmium contamination in paddy soils under long-term remediation measures: Model development and stochastic simulations.

    Science.gov (United States)

    Peng, Chi; Wang, Meie; Chen, Weiping

    2016-09-01

    A pollutant accumulation model (PAM) based on the mass balance theory was developed to simulate long-term changes of heavy metal concentrations in soil. When combined with Monte Carlo simulation, the model can predict the probability distributions of heavy metals in a soil-water-plant system with fluctuating environmental parameters and inputs from multiple pathways. The model was used for evaluating different remediation measures to deal with Cd contamination of paddy soils in Youxian county (Hunan province), China, under five scenarios, namely the default scenario (A), not returning paddy straw to the soil (B), reducing the deposition of Cd (C), liming (D), and integrating several remediation measures (E). The model predicted that the Cd contents of soil can lowered significantly by (B) and those of the plants by (D). However, in the long run, (D) will increase soil Cd. The concentrations of Cd in both soils and rice grains can be effectively reduced by (E), although it will take decades of effort. The history of Cd pollution and the major causes of Cd accumulation in soil were studied by means of sensitivity analysis and retrospective simulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Remediation of cadmium-contaminated paddy soils by washing with calcium chloride: Verification of on-site washing

    International Nuclear Information System (INIS)

    Makino, Tomoyuki; Kamiya, Takashi; Takano, Hiroyuki; Itou, Tadashi; Sekiya, Naoki; Sasaki, Kouta; Maejima, Yuji; Sugahara, Kazuo

    2007-01-01

    We developed a new, three-step soil-wash method to remediate Cd-contaminated paddy fields. The method comprises (1) chemically washing the field soil with a CaCl 2 solution; (2) washing the treated soil with water to eliminate residual Cd and CaCl 2 ; and (3) on-site treatment of wastewater using a portable wastewater treatment system. Cd concentrations in the treated water were below Japan's environmental quality standard (0.01 mg Cd L -1 ), and the removal of Cd from the exchangeable fraction was 55% and from the acid-soluble fraction 15%. While soil fertility properties were affected by the soil washing, adverse effects were not crucial and could be corrected. The washing had no affect on rice growth, and reduced the average Cd concentration in rice grains by about two-thirds compared to a control plot. These results confirmed the effectiveness of the soil-wash method in remediating Cd-contaminated paddy fields. - In situ soil washing in a paddy field using an on-site wastewater treatment system resulted in an effective decrease of Cd in soil and rice grains without affecting rice yield

  17. Ecopiling: A combined Phytoremediation and Passive Biopiling System for Remediating Hydrocarbon Impacted Soils at Field Scale

    Directory of Open Access Journals (Sweden)

    Kieran J Germaine

    2015-01-01

    Full Text Available Biopiling is an ex situ bioremediation technology that has been extensively used for remediating a wide range of petrochemical contaminants in soils. Biopiling involves the assembling of contaminated soils into piles and stimulating the biodegrading activity of microbial populations by creating near optimum growth conditions. Phytoremediation is another very successful bioremediation technique and involves the use of plants and their associated microbiomes to degrade, sequester or bio-accumulate pollutants from contaminated soil and water. The objective of this study was to investigate the effectiveness of a combined phytoremediation/biopiling system, termed Ecopiling, to remediate hydrocarbon impacted industrial soil. The large scale project was carried out on a sandy loam, petroleum impacted soil (1613 mg Total Petroleum Hydrocarbons (TPH kg-1 soil. The contaminated soil was amended with chemical fertilisers, inoculated with TPH degrading bacterial consortia and then used to construct passive biopiles. Finally, a phyto-cap of perennial rye grass (Lolium multiflorum and white clover (Trifolium repens was sown on the soil surface to complete the Ecopile. Monitoring of important physico-chemical parameters was carried out at regular intervals throughout the trial. Two years after construction the TPH levels in the petroleum impacted Ecopiles were below detectable limits in all but 1 subsample (152mg TPH kg-1 soil. The Ecopile system is a multi-factorial bioremediation process involving bio-stimulation, bio-augmentation and phytoremediation. One of the key advantages to this system is the reduced costs of the remediation process, as once constructed, there is little additional cost in terms of labour and maintenance (although the longer process time may incur additional monitoring costs. The other major advantage is that many ecological functions are rapidly restored to the site and the process is aesthetically pleasing.

  18. Ecopiling: a combined phytoremediation and passive biopiling system for remediating hydrocarbon impacted soils at field scale.

    Science.gov (United States)

    Germaine, Kieran J; Byrne, John; Liu, Xuemei; Keohane, Jer; Culhane, John; Lally, Richard D; Kiwanuka, Samuel; Ryan, David; Dowling, David N

    2014-01-01

    Biopiling is an ex situ bioremediation technology that has been extensively used for remediating a wide range of petrochemical contaminants in soils. Biopiling involves the assembling of contaminated soils into piles and stimulating the biodegrading activity of microbial populations by creating near optimum growth conditions. Phytoremediation is another very successful bioremediation technique and involves the use of plants and their associated microbiomes to degrade, sequester or bio-accumulate pollutants from contaminated soil and water. The objective of this study was to investigate the effectiveness of a combined phytoremediation/biopiling system, termed Ecopiling, to remediate hydrocarbon impacted industrial soil. The large scale project was carried out on a sandy loam, petroleum impacted soil [1613 mg total petroleum hydrocarbons (TPHs) kg(-1) soil]. The contaminated soil was amended with chemical fertilizers, inoculated with TPH degrading bacterial consortia and then used to construct passive biopiles. Finally, a phyto-cap of perennial rye grass (Lolium perenne) and white clover (Trifolium repens) was sown on the soil surface to complete the Ecopile. Monitoring of important physico-chemical parameters was carried out at regular intervals throughout the trial. Two years after construction the TPH levels in the petroleum impacted Ecopiles were below detectable limits in all but one subsample (152 mg TPH kg(-1) soil). The Ecopile system is a multi-factorial bioremediation process involving bio-stimulation, bio-augmentation and phytoremediation. One of the key advantages to this system is the reduced costs of the remediation process, as once constructed, there is little additional cost in terms of labor and maintenance (although the longer process time may incur additional monitoring costs). The other major advantage is that many ecological functions are rapidly restored to the site and the process is esthetically pleasing.

  19. Implications of soil mixing for NAPL source zone remediation: Column studies and modeling of field-scale systems.

    Science.gov (United States)

    Olson, Mitchell R; Sale, Tom C

    2015-01-01

    Soil remediation is often inhibited by subsurface heterogeneity, which constrains contaminant/reagent contact. Use of soil mixing techniques for reagent delivery provides a means to overcome contaminant/reagent contact limitations. Furthermore, soil mixing reduces the permeability of treated soils, thus extending the time for reactions to proceed. This paper describes research conducted to evaluate implications of soil mixing on remediation of non-aqueous phase liquid (NAPL) source zones. The research consisted of column studies and subsequent modeling of field-scale systems. For column studies, clean influent water was flushed through columns containing homogenized soils, granular zero valent iron (ZVI), and trichloroethene (TCE) NAPL. Within the columns, NAPL depletion occurred due to dissolution, followed by either column-effluent discharge or ZVI-mediated degradation. Complete removal of TCE NAPL from the columns occurred in 6-8 pore volumes of flow. However, most of the TCE (>96%) was discharged in the column effluent; less than 4% of TCE was degraded. The low fraction of TCE degraded is attributed to the short hydraulic residence time (10 m) and reducing permeability by one-or-more orders of magnitude, the residence time could be greatly extended, potentially for periods of years to decades. Model output indicates that the fraction of TCE degraded can be increased to >99.9%, given typical post-mixing soil permeability values. These results suggest that remediation performance can be greatly enhanced by combining contaminant degradation with an extended residence time. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Remediation of trichloroethylene-contaminated soils by star technology using vegetable oil smoldering.

    Science.gov (United States)

    Salman, Madiha; Gerhard, Jason I; Major, David W; Pironi, Paolo; Hadden, Rory

    2015-03-21

    Self-sustaining treatment for active remediation (STAR) is an innovative soil remediation approach based on smoldering combustion that has been demonstrated to effectively destroy complex hydrocarbon nonaqueous phase liquids (NAPLs) with minimal energy input. This is the first study to explore the smoldering remediation of sand contaminated by a volatile NAPL (trichloroethylene, TCE) and the first to consider utilizing vegetable oil as supplemental fuel for STAR. Thirty laboratory-scale experiments were conducted to evaluate the relationship between key outcomes (TCE destruction, rate of remediation) to initial conditions (vegetable oil type, oil: TCE mass ratio, neat versus emulsified oils). Several vegetable oils and emulsified vegetable oil formulations were shown to support remediation of TCE via self-sustaining smoldering. A minimum concentration of 14,000 mg/kg canola oil was found to treat sand exhibiting up to 80,000 mg/kg TCE. On average, 75% of the TCE mass was removed due to volatilization. This proof-of-concept study suggests that injection and smoldering of vegetable oil may provide a new alternative for driving volatile contaminants to traditional vapour extraction systems without supplying substantial external energy. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Secondary successions of biota in oil-polluted peat soil upon different biological remediation methods

    Science.gov (United States)

    Melekhina, E. N.; Markarova, M. Yu.; Shchemelinina, T. N.; Anchugova, E. M.; Kanev, V. A.

    2015-06-01

    The effects of different bioremediation methods on restoration of the oil-polluted peat soil (Histosol) in the northernmost taiga subzone of European Russia was studied. The population dynamics of microorganisms belonging to different trophic groups (hydrocarbon-oxidizing, ammonifying, nitrifying, and oligonitrophilic) were analyzed together with data on the soil enzyme (catalase and dehydrogenase) activities, population densities of soil microfauna groups, their structures, and states of phytocenoses during a sevenyear-long succession. The remediation with biopreparations Roder composed of oil-oxidizing microorganisms-Roder with Rhodococcus rubber and R. erythropolis and Universal with Rhodotorula glutinis and Rhodococcus sp.-was more efficient than the agrochemical and technical remediation. It was concluded that the biopreparations activate microbiological oil destruction, thereby accelerating restoration succession of phytocenosis and zoocenosis. The succession of dominant microfauna groups was observed: the dipteran larvae and Mesostigmata mites predominant at the early stages were replaced by collembolans at later stages. The pioneer oribatid mite species were Tectocepheus velatus, Oppiella nova, Liochthonius sellnicki, Oribatula tibialis, and Eupelops sp.

  2. Elemental composition study of heavy metal (Ni, Cu, Zn) in riverbank soil by electrokinetic-assisted phyto remediation using XRF and SEM/EDX

    International Nuclear Information System (INIS)

    Suhailly Jamari; Zaidi Embong; Zaidi Embong; Ismail Bakar

    2013-01-01

    Full-text: Electrokinetic (EK)-assisted phyto remediation is one of the methods that have a big potential in enhancing the ability of plant uptake in soils remediation process. This research was conducted to investigate the difference in elemental composition concentration of riverbank soil and the change of pH between pre- and post-phyto remediation under the following condition: 1) control or as-receive sample; 2) Dieffenbachia spp plant with EK system (a pair of EK electrodes connected to a direct current (DC) power supply). After the electrodes were connected to a magnitude of 6 V/ cm -1 electric field for 4 hours/ day, the soil and plant samples were analyzed using and X-ray Fluorescence Spectrometer (XRF) and Scanning Electron Microscope/ Energy Dispersive X-ray Spectroscopy (SEM/ EDX). The SEM/EDX analysis showed that concentration of elemental composition (Ni, Cu and Zn) in post-phyto remediation plant powder samples had increase while elemental concentrations in the post-hydrotreatment soil samples were decreased. XRF analysis presented a variation in soil elemental composition concentration from anode to cathode where the concentration near anode region increased while decreased near the cathode region. A significant changes in soil pH were obtained where the soil pH increase in cathode region while decrease in anode region. The results reveal that the assistance of EK in phyto remediation process has increase the efficiency of plant uptake. (author)

  3. Remediation of Cr(VI) contaminated soil using long-duration sodium thiosulfate supported by micro–nano networks

    International Nuclear Information System (INIS)

    He, Lulu; Wang, Min; Zhang, Guilong; Qiu, Guannan; Cai, Dongqing; Wu, Zhengyan; Zhang, Xin

    2015-01-01

    Highlights: • This work aims to develop a long-duration remediation agent (LRA). • LRA was obtained using Na 2 S 2 O 3 supported by attapulgite (ATP) micro–nano networks. • ATP micro–nano networks was induced by high-energy electron beam irradiation. • LRA can effectively control the migration of Cr(VI) and reducing Cr(VI) to Cr(III). • LRA displayed high performance on the remediation of heavy metal contaminated soil. - Abstract: In this work, a long-duration remediation agent (LRA) on hexavalent chromium (Cr(VI)) was developed using sodium thiosulfate (ST) supported by attapulgite (ATP) micro–nano networks induced through high-energy electron beam (HEEB) irradiation. The ATP networks could effectively reduce the leaching amount of Cr(VI) in soil. More importantly, the ATP networks could significantly control the leaching behavior of ST, and then prolong the duration and increase the reduction efficiency of ST on Cr(VI). As a result, LRA displayed high performance on controlling the migration of Cr(VI) and reducing Cr(VI) to Cr(III). Additionally, pot experiment indicated that LRA could effectively decrease the absorbed amount of Cr(VI) in corn, and reduce the inhibition effect of Cr(VI) on the growth of corn. Therefore, this work could provide a facile approach to remediate the Cr(VI)-contaminated soil and lower the harmful effect of Cr(VI) on crop

  4. Remediation of Cr(VI) contaminated soil using long-duration sodium thiosulfate supported by micro–nano networks

    Energy Technology Data Exchange (ETDEWEB)

    He, Lulu [School of Life Sciences, Anhui Agricultural University, Hefei 230036 (China); Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Wang, Min; Zhang, Guilong [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Qiu, Guannan [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Cai, Dongqing, E-mail: dqcai@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Wu, Zhengyan, E-mail: zywu@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Zhang, Xin, E-mail: xinzhang@ahau.edu.cn [School of Life Sciences, Anhui Agricultural University, Hefei 230036 (China)

    2015-08-30

    Highlights: • This work aims to develop a long-duration remediation agent (LRA). • LRA was obtained using Na{sub 2}S{sub 2}O{sub 3} supported by attapulgite (ATP) micro–nano networks. • ATP micro–nano networks was induced by high-energy electron beam irradiation. • LRA can effectively control the migration of Cr(VI) and reducing Cr(VI) to Cr(III). • LRA displayed high performance on the remediation of heavy metal contaminated soil. - Abstract: In this work, a long-duration remediation agent (LRA) on hexavalent chromium (Cr(VI)) was developed using sodium thiosulfate (ST) supported by attapulgite (ATP) micro–nano networks induced through high-energy electron beam (HEEB) irradiation. The ATP networks could effectively reduce the leaching amount of Cr(VI) in soil. More importantly, the ATP networks could significantly control the leaching behavior of ST, and then prolong the duration and increase the reduction efficiency of ST on Cr(VI). As a result, LRA displayed high performance on controlling the migration of Cr(VI) and reducing Cr(VI) to Cr(III). Additionally, pot experiment indicated that LRA could effectively decrease the absorbed amount of Cr(VI) in corn, and reduce the inhibition effect of Cr(VI) on the growth of corn. Therefore, this work could provide a facile approach to remediate the Cr(VI)-contaminated soil and lower the harmful effect of Cr(VI) on crop.

  5. Integrated electrokinetics-adsorption remediation of saline-sodic soils: effects of voltage gradient and contaminant concentration on soil electrical conductivity.

    Science.gov (United States)

    Essa, Mohammed Hussain; Mu'azu, Nuhu Dalhat; Lukman, Salihu; Bukhari, Alaadin

    2013-01-01

    In this study, an integrated in situ remediation technique which couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic clay soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg), was used in this study to investigate the effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil electrical conductivity. Box-Behnken Design (BBD) was used for the experimental design and response surface methodology (RSM) was employed to model, optimize, and interpret the results obtained using Design-Expert version 8 platform. The total number of experiments conducted was 15 with voltage gradient, polarity reversal rate, and initial contaminant concentration as variables. The main target response discussed in this paper is the soil electrical conductivity due to its importance in electrokinetic remediation process. Responses obtained were fitted to quadratic models whose R (2) ranges from 84.66% to 99.19% with insignificant lack of fit in each case. Among the investigated factors, voltage gradient and initial contaminant concentration were found to be the most significant influential factors.

  6. Integrated Electrokinetics-Adsorption Remediation of Saline-Sodic Soils: Effects of Voltage Gradient and Contaminant Concentration on Soil Electrical Conductivity

    Directory of Open Access Journals (Sweden)

    Mohammed Hussain Essa

    2013-01-01

    Full Text Available In this study, an integrated in situ remediation technique which couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic clay soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg, was used in this study to investigate the effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil electrical conductivity. Box-Behnken Design (BBD was used for the experimental design and response surface methodology (RSM was employed to model, optimize, and interpret the results obtained using Design-Expert version 8 platform. The total number of experiments conducted was 15 with voltage gradient, polarity reversal rate, and initial contaminant concentration as variables. The main target response discussed in this paper is the soil electrical conductivity due to its importance in electrokinetic remediation process. Responses obtained were fitted to quadratic models whose R2 ranges from 84.66% to 99.19% with insignificant lack of fit in each case. Among the investigated factors, voltage gradient and initial contaminant concentration were found to be the most significant influential factors.

  7. Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil.

    Science.gov (United States)

    Li, Xiaojing; Wang, Xin; Ren, Zhiyong Jason; Zhang, Yueyong; Li, Nan; Zhou, Qixing

    2015-12-01

    Bioelectrochemical system is an emerging technology for the remediation of soils contaminated by petroleum hydrocarbons. However, performance of such systems can be limited by the inefficient mass transport in soil. Here we report a new method of sand amendment, which significantly increases both oxygen and proton transports, resulting to increased soil porosity (from 44.5% to 51.3%), decreased Ohmic resistance (by 46%), and increased charge output (from 2.5 to 3.5Cg(-1)soil). The degradation rates of petroleum hydrocarbons increased by up to 268% in 135d. The degradation of n-alkanes and polycyclic aromatic hydrocarbons with high molecular weight was accelerated, and denaturing gradient gel electrophoresis showed that the microbial community close to the air-cathode was substantially stimulated by the induced current, especially the hydrocarbon degrading bacteria Alcanivorax. The bioelectrochemical stimulation imposed a selective pressure on the microbial community of anodes, including that far from the cathode. These results suggested that sand amendment can be an effective approach for soil conditioning that will enhances the bioelectrochemical removal of hydrocarbons in contaminated soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Research Progress of Artificial Forest in the Remediation of Heavy Metal Contaminated Soils

    Science.gov (United States)

    Jiafang, MA; Guangtao, MENG; Liping, HE; Guixiang, LI

    2017-01-01

    (1) Remediation of soil contaminated by heavy metals has become a hot topic in the world, and phytoremediation technology is the most widely used. (2) In addition to traditional economic benefits, ecological benefits of artificial forest have been more and more important, which are very helpful to soil polluted with heavy metals in the environment. (3) The characteristics of heavy metal pollution of soil and plantations of repair mechanism have been reviewed, and the current mining areas, wetlands, urban plantations on heavy metal elements have enriched the research results. The purpose is to find a new path for governance of heavy metal soil pollution.

  9. Microbial metabolism and community structure in response to bioelectrochemically enhanced remediation of petroleum hydrocarbon-contaminated soil.

    Science.gov (United States)

    Lu, Lu; Huggins, Tyler; Jin, Song; Zuo, Yi; Ren, Zhiyong Jason

    2014-04-01

    This study demonstrates that electrodes in a bioelectrochemical system (BES) can potentially serve as a nonexhaustible electron acceptor for in situ bioremediation of hydrocarbon contaminated soil. The deployment of BES not only eliminates aeration or supplement of electron acceptors as in contemporary bioremediation but also significantly shortens the remediation period and produces sustainable electricity. More interestingly, the study reveals that microbial metabolism and community structure distinctively respond to the bioelectrochemically enhanced remediation. Tubular BESs with carbon cloth anode (CCA) or biochar anode (BCA) were inserted into raw water saturated soils containing petroleum hydrocarbons for enhancing in situ remediation. Results show that total petroleum hydrocarbon (TPH) removal rate almost doubled in soils close to the anode (63.5-78.7%) than that in the open circuit positive controls (37.6-43.4%) during a period of 64 days. The maximum current density from the BESs ranged from 73 to 86 mA/m(2). Comprehensive microbial and chemical characterizations and statistical analyses show that the residual TPH has a strongly positive correlation with hydrocarbon-degrading microorganisms (HDM) numbers, dehydrogenase activity, and lipase activity and a negative correlation with soil pH, conductivity, and catalase activity. Distinctive microbial communities were identified at the anode, in soil with electrodes, and soil without electrodes. Uncommon electrochemically active bacteria capable of hydrocarbon degradation such as Comamonas testosteroni, Pseudomonas putida, and Ochrobactrum anthropi were selectively enriched on the anode, while hydrocarbon oxidizing bacteria were dominant in soil samples. Results from genus or phylum level characterizations well agree with the data from cluster analysis. Data from this study suggests that a unique constitution of microbial communities may play a key role in BES enhancement of petroleum hydrocarbons

  10. Alleviation of Heavy Metal Stress in Plants and Remediation of Soil by Rhizosphere Microorganisms

    Directory of Open Access Journals (Sweden)

    Jitendra Mishra

    2017-09-01

    Full Text Available Increasing concentration of heavy metals (HM due to various anthropogenic activities is a serious problem. Plants are very much affected by HM pollution particularly in contaminated soils. Survival of plants becomes tough and its overall health under HM stress is impaired. Remediation of HM in contaminated soil is done by physical and chemical processes which are costly, time-consuming, and non-sustainable. Metal–microbe interaction is an emerging but under-utilized technology that can be exploited to reduce HM stress in plants. Several rhizosphere microorganisms are known to play essential role in the management of HM stresses in plants. They can accumulate, transform, or detoxify HM. In general, the benefit from these microbes can have a vast impact on plant’s health. Plant–microbe associations targeting HM stress may provide another dimension to existing phytoremediation and rhizoremediation uses. In this review, applied aspects and mechanisms of action of heavy metal tolerant-plant growth promoting (HMT-PGP microbes in ensuring plant survival and growth in contaminated soils are discussed. The use of HMT-PGP microbes and their interaction with plants in remediation of contaminated soil can be the approach for the future. This low input and sustainable biotechnology can be of immense use/importance in reclaiming the HM contaminated soils, thus increasing the quality and yield of such soils.

  11. Alleviation of Heavy Metal Stress in Plants and Remediation of Soil by Rhizosphere Microorganisms.

    Science.gov (United States)

    Mishra, Jitendra; Singh, Rachna; Arora, Naveen K

    2017-01-01

    Increasing concentration of heavy metals (HM) due to various anthropogenic activities is a serious problem. Plants are very much affected by HM pollution particularly in contaminated soils. Survival of plants becomes tough and its overall health under HM stress is impaired. Remediation of HM in contaminated soil is done by physical and chemical processes which are costly, time-consuming, and non-sustainable. Metal-microbe interaction is an emerging but under-utilized technology that can be exploited to reduce HM stress in plants. Several rhizosphere microorganisms are known to play essential role in the management of HM stresses in plants. They can accumulate, transform, or detoxify HM. In general, the benefit from these microbes can have a vast impact on plant's health. Plant-microbe associations targeting HM stress may provide another dimension to existing phytoremediation and rhizoremediation uses. In this review, applied aspects and mechanisms of action of heavy metal tolerant-plant growth promoting (HMT-PGP) microbes in ensuring plant survival and growth in contaminated soils are discussed. The use of HMT-PGP microbes and their interaction with plants in remediation of contaminated soil can be the approach for the future. This low input and sustainable biotechnology can be of immense use/importance in reclaiming the HM contaminated soils, thus increasing the quality and yield of such soils.

  12. MICHIGAN SOIL VAPOR EXTRACTION REMEDIATION (MISER) MODEL: A COMPUTER PROGRAM TO MODEL SOIL VAPOR EXTRACTION AND BIOVENTING OF ORGANIC CHEMICALS IN UNSATURATED GEOLOGICAL MATERIAL

    Science.gov (United States)

    Soil vapor extraction (SVE) and bioventing (BV) are proven strategies for remediation of unsaturated zone soils. Mathematical models are powerful tools that can be used to integrate and quantify the interaction of physical, chemical, and biological processes occurring in field sc...

  13. Use of composts in the remediation of heavy metal contaminated soil.

    Science.gov (United States)

    Farrell, Mark; Jones, Davey L

    2010-03-15

    High levels of heavy metals in soil can ultimately lead to pollution of drinking water and contamination of food. Consequently, sustainable remediation strategies for treating soil are required. The potential ameliorative effect of several composts derived from source-separated and mixed municipal wastes were evaluated in a highly acidic heavily contaminated soil (As, Cu, Pb, Zn) in the presence and absence of lime. Overall, PTE (potentially toxic element) amelioration was enhanced by compost whilst lime had little effect and even exacerbated PTE mobilization (e.g. As). All composts reduced soil solution PTE levels and raised soil pH and nutrient levels and are well suited to revegetation of contaminated sites. However, care must be taken to ensure correct pH management (pH 5-6) to optimize plant growth whilst minimizing PTE solubilization, particularly at high pH. In addition, 'metal excluder' species should be sown to minimize PTE entry into the food chain. (c) 2009 Elsevier B.V. All rights reserved.

  14. The use of in-situ dual vacuum extraction for remediation of soil and groundwater

    International Nuclear Information System (INIS)

    Trowbridge, B.E.; Ott, D.E.

    1992-01-01

    Dual Extraction provides a rapid and cost-effective method of remediating soil and groundwater impacted by volatile organic compounds (VOC's). Dual Extraction is the removal of both water and vapors through the same borehole using entrainment. This technology provides for the remediation of the vadose zone, capillary fringe, smear zone, and existing water table. The effectiveness of this technology is shown in a case study. A release from an Underground Storage Tank (UST) was responsible for a hydrocarbon plume spreading over approximately 50,000 square feet. The release produced vadose zone contamination in the silty and sandy clays from 10 - 30 feet below ground surface with TPH concentrations up to 1,400 mg/kg. A layer of free floating liquid hydrocarbon was present on a shallow aquifer located at 30 feet bgs in thicknesses ranging from 0.5 feet to 3.0 feet. An in-situ dual-extraction system was installed to remediate the soils and groundwater to levels as required by the Los Angeles Regional Water Quality Control Board (RWQCB). The system operated 24 hours/day for 196 days with an operating efficiency of over 99%. After 196 days, over 17,000 pounds of hydrocarbons had been extracted from the soils. Seven confirmatory soil borings were advanced in the area of highest initial hydrocarbon concentrations and indicated that TPH and BTEX concentrations had decreased over 99% from initial soil concentrations. Three confirmatory groundwater samples were obtained from monitoring wells initially exhibiting up to 3 feet of floating product. Confirmatory samples exhibited non-detectable (ND) concentrations of TPH and BTEX. Based upon the positive confirmatory results, site closure was obtained from the RWQCB in May of 1991. In only 28 weeks of operation, the groundwater contamination was reduced from free floating product to non-detectable concentrations of TPH using Dual Vacuum Extraction

  15. Assessment of the Use of Natural Materials for the Remediation of Cadmium Soil Contamination

    OpenAIRE

    de O. Pinto, Tatiana; Garc?a, Andr?s C.; Guedes, Jair do N.; do A. Sobrinho, Nelson M. B.; Tavares, Orlando C. H.; Berbara, Ricardo L. L.

    2016-01-01

    Rice plants accumulate cadmium (Cd2+) within the grain, increasing the danger of human exposure. Natural materials have been used in soil remediation, but few studies have examined the risks (based on the bioavailability of these metals to plants) of using these materials, so the practice remains controversial. In the present study, we evaluated the effectiveness of biochar produced from sugarcane bagasse, vermicompost (VC), vermicompost solid residue (VCR) and humin for remediation of Cd2+-c...

  16. Feasibility Study of the Use of Thiosulfate as Extractant Agent in the Electrokinetic Remediation of a Soil Contaminated by Mercury from Almadén

    DEFF Research Database (Denmark)

    Subires-Muñoz, José Diego; García-Rubio, Ana; Vereda-Alonso, Carlos

    2010-01-01

    Natural soils are rather complex, making the predictability of the behavior of some remediation techniques very complicated. In this paper, the remediation of a Hg contaminated soil close to Almadén using a thiosulfate solution as extractant agent is studied. In addition, the use of the BCR...... extraction procedure before and after the remediation was performed. Once again, a clear relationship between the remediation and the extraction results are observed, giving further support to the idea that BCR can be used as a reasonable tool for feasibility studies of EKR among other remediation techniques....

  17. Remediation and recycling of oil-contaminated soil beneath a large above-ground storage tank

    International Nuclear Information System (INIS)

    Wallace, G.

    1994-01-01

    While retrofitting a large 30-year-old, above-ground petroleum storage tank, Southern California Edison Company (SCE) discovered that soil beneath the fixed-roof, single-bottom tank was contaminated with 40,000 gallons of number-sign 6 fuel oil. The steel tank was left in place during the excavation and remediation of the contaminated soil to retain the operating permit. The resulting 2,000 tons of contaminated aggregate was recycled to make asphalt concrete for paving the tank basin and the remaining 5,600 tons of oily soil was thermally treated on site for use as engineered fill at another location. This successful operation provided an economical cleanup solution for a common leakage problem of single-lined tanks and eliminated the long-term liability of Class 1 landfill disposal. As a pro-active environmental effort, this paper shares SCE's site assessment procedure, reveals the engineering method developed to stabilize the tank, discusses the soil treatment technologies used, describes the problems encountered and lessons learned during the cleanup, discloses the costs of the operation, and offers guidelines and recommendations for similar tank remediation. This paper does not describe the work or costs for removing or replacing the tank bottom

  18. Glyphosate contaminated soil remediation by atmospheric pressure dielectric barrier discharge plasma and its residual toxicity evaluation.

    Science.gov (United States)

    Wang, Tiecheng; Ren, Jingyu; Qu, Guangzhou; Liang, Dongli; Hu, Shibin

    2016-12-15

    Glyphosate was one of the most widely used herbicides in the world. Remediation of glyphosate-contaminated soil was conducted using atmospheric pressure dielectric barrier discharge (DBD) plasma. The feasibility of glyphosate degradation in soil was explored, and the soil leachate toxicity after remediation was assessed via a seed germination test. The experimental results showed that approximately 93.9% of glyphosate was degraded within 45min of DBD plasma treatment with an energy yield of 0.47gkWh -1 , and the degradation process fitted the first-order kinetic model. Increasing the discharge voltage and decreasing the organic matter content of the soil were both found to facilitate glyphosate degradation. There existed appropriate soil moisture to realize high glyphosate degradation efficiency. Glyphosate mineralization was confirmed by changes of total organic carbon (TOC), chemical oxygen demand (COD), PO 4 3- and NO 3 - . The degradation intermediates including glycine, aminomethylphosphonic acid, acetic acid, formic acid, PO 4 3- and NO 3 - , CO 2 and CO were observed. A possible pathway for glyphosate degradation in the soil using this system was proposed. Based on the soil leachate toxicity test using wheat seed germination, the soil did not exhibit any hazardous effects following high-efficiency glyphosate degradation. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. RECARE - Preventing and Remediating Degradation of Soils in Europe through Landcare.

    Science.gov (United States)

    van den Elsen, Erik; Hessel, Rudi; Verzandvoort, Simone; Ritsema, Coen; Geissen, Violette

    2015-04-01

    Although there is a large body of knowledge available on soil threats in Europe, this knowledge is fragmented and incomplete, in particular regarding the complexity and functioning of soil systems and their interaction with human activities. The main aim of the RECARE project is to develop effective prevention, remediation and restoration measures using an innovative trans-disciplinary approach, actively integrating and advancing knowledge of stakeholders and scientists in 17 Case Studies, covering a range of soil threats in different bio-physical and socio-economic environments across Europe. Within these Case Study sites, i) the current state of degradation and conservation will be assessed using a new methodology, based on the WOCAT mapping procedure, ii) impacts of degradation and conservation on soil functions and ecosystem services will be quantified in a harmonized, spatially explicit way, accounting for costs and benefits, and possible trade-offs, iii) prevention, remediation and restoration measures selected and implemented by stakeholders in a participatory process will be evaluated regarding efficacy, and iv) the applicability and impact of these measures at the European level will be assessed using a new integrated bio-physical and socio-economic model, accounting for land use dynamics as a result of for instance economic development and policies. Existing national and EU policies will be reviewed and compared to identify potential incoherence, contradictions and synergies. Policy messages will be formulated based on the Case Study results and their integration at European level. A comprehensive dissemination and communication strategy, including the development of a web-based Dissemination and Communication Hub, will accompany the other activities to ensure that project results are disseminated to a variety of stakeholders at the right time and in the appropriate formats to stimulate renewed care for European soils.

  20. Citric-acid preacidification enhanced electrokinetic remediation for removal of chromium from chromium-residue-contaminated soil.

    Science.gov (United States)

    Meng, Fansheng; Xue, Hao; Wang, Yeyao; Zheng, Binghui; Wang, Juling

    2018-02-01

    Electrokinetic experiments were conducted on chromium-residue-contaminated soils collected from a chemical plant in China. Acidification-electrokinetic remediation technology was proposed in order to solve the problem of removing inefficient with ordinary electrokinetic. The results showed that electrokinetic remediation removal efficiency of chromium from chromium-contaminated soil was significantly enhanced with acidizing pretreatment. The total chromium [Cr(T)] and hexavalent chromium [Cr(VI)] removal rate of the group acidized by citric acid (0.9 mol/L) for 5 days was increased from 6.23% and 19.01% in the acid-free experiments to 26.97% and 77.66% in the acidification-treated experiments, respectively. In addition, part of chromium with the state of carbonate-combined will be converted into water-soluble state through acidification to improve the removal efficiency. Within the appropriate concentration range, the higher concentration of acid was, the more chromium was released. So the removal efficiency of chromium depended on the acid concentration. The citric acid is also a kind of complexing agent, which produced complexation with Cr that was released by the electrokinetic treatment and then enhanced the removal efficiency. The major speciation of chromium that was removed from soils by acidification-electrokinetics remediation was acid-soluble speciation, revivification speciation and oxidation speciation, which reduced biological availability of chromium.

  1. Biochar- and phosphate-induced immobilization of heavy metals in contaminated soil and water: implication on simultaneous remediation of contaminated soil and groundwater.

    Science.gov (United States)

    Liang, Yuan; Cao, Xinde; Zhao, Ling; Arellano, Eduardo

    2014-03-01

    Long-term wastewater irrigation or solid waste disposal has resulted in the heavy metal contamination in both soil and groundwater. It is often separately implemented for remediation of contaminated soil or groundwater at a specific site. The main objective of this study was to demonstrate the hypothesis of simultaneous remediation of both heavy metal contaminated soil and groundwater by integrating the chemical immobilization and pump-and-treat methods. To accomplish the objective, three experiments were conducted, i.e., an incubation experiment was first conducted to determine how dairy-manure-derived biochar and phosphate rock tailing induced immobilization of Cd in the Cd-contaminated soils; second, a batch sorption experiment was carried out to determine whether the pre-amended contaminated soil still had the ability to retain Pb, Zn and Cd from aqueous solution. BCR sequential extraction as well as XRD and SEM analysis were conducted to explore the possible retention mechanism; and last, a laboratory-scale model test was undertaken by leaching the Pb, Zn, and Cd contaminated groundwater through the pre-amended contaminated soils to demonstrate how the heavy metals in both contaminated soil and groundwater were simultaneously retained and immobilized. The incubation experiment showed that the phosphate biochar were effective in immobilizing soil Cd with Cd concentration in TCLP (toxicity characteristics leaching procedure) extract reduced by 19.6 % and 13.7 %, respectively. The batch sorption experiment revealed that the pre-amended soil still had ability to retain Pb, Zn, and Cd from aqueous solution. The phosphate-induced metal retention was mainly due to the metal-phosphate precipitation, while both sorption and precipitation were responsible for the metal stabilization in the biochar amendment. The laboratory-scale test demonstrated that the soil amended with phosphate removed groundwater Pb, Zn, and Cd by 96.4 %, 44.6 %, and 49.2 %, respectively, and the

  2. Reliability and stability of immobilization remediation of Cd polluted soils using sepiolite under pot and field trials.

    Science.gov (United States)

    Sun, Yuebing; Xu, Yi; Xu, Yingming; Wang, Lin; Liang, Xuefeng; Li, Ye

    2016-01-01

    Long-term effectiveness and persistence are two important criterias to evaluate alternative remediation technology of heavy metal polluted soils. Pot and field studies showed addition of sepiolite was effective in immobilizing Cd in polluted soils, with significant reduction in TCLP extracts (0.6%-49.6% and 4.0%-32.5% reduction in pot and field experiments, respectively) and plant uptake (14.4%-84.1% and 22.8%-61.4% declines in pot and field studies, correspondingly). However, the applications of sepiolite offered a limited guarantee for the safety of edible vegetables in Cd-polluted soils, depending on the soil type, the Cd pollution type and level, and the dose and application frequency of chemical amendments. Bioassays, such as plant growth, soil enzymatic activities and microbial community diversity, indicated a certain degree of recovery of soil metabolic function. Therefore, sepiolite-assisted in situ remediation is cost-effective, environmentally friendly, and technically applicable, and can be successfully used to reduce Cd enter into the food chain on field scale. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Site remediation: The naked truth

    International Nuclear Information System (INIS)

    Calloway, J.M.

    1991-01-01

    The objective of any company faced with an environmental site remediation project is to perform the cleanup effectively at the lowest possible cost. Today, there are a variety of techniques being applied in the remediation of sites involving soils and sludges. The most popular include: stabilization, incineration, bioremediation and off-site treatment. Dewatering may also play an integral role in a number of these approaches. Selecting the most cost-effective technique for remediation of soils and sludges can be a formidable undertaking, namely because it is often difficult to quantify certain expenses in advance of the project. In addition to providing general cost guidelines for various aspects of soil and sludge remediation, this paper will show how some significant cost factors can be affected by conditions related to specific remediation projects and the cleanup technology being applied

  4. Decision support tools for evaluation and selection of technologies for soil remediation and disposal of halogenated waste

    Energy Technology Data Exchange (ETDEWEB)

    Khelifi, O.; Zinovyev, S.; Lodolo, A.; Vranes, S.; Miertus, S. [ICS-UNIDO, Trieste (Italy)

    2004-09-15

    One of the most justified demands in abating the pollution created by polychlorinated substances is the remediation of contaminated sites, mainly soil remediation, which is also the most complex technical task in removing pollution because of the necessity to process huge quantities of matrix and to account for numerous side factors. The commercial technologies are usually based on rather direct and simplified but also secure processes, which often approach remediation in a general way, where different types of pollutants can be decontaminated at the same time by each technology. A number of different soil remediation technologies are nowadays available and the continuous competition among environmental service companies and technology developers generates a further increase in the clean-up options. The demand for decision support tools that could help decision makers in selecting the most appropriate technology for the specific contaminated site has consequently increased. These decision support tools (DST) are designed to help decision makers (site owners, local community representatives, environmentalists, regulators, etc.) to assess available technologies and preliminarily select the preferred remedial options. The analysis for the identification of the most suitable options in the DST is based on technical, economic, environmental, and social criteria. These criteria are ranked by all parties involved in the decision process to determine their relative importance for a particular remediation project. The aim of the present paper is to present the new approach for building decision support tool to evaluate different technologies for remediation and disposal of halogenated waste.

  5. Remediation of soil/concrete contaminated with uranium and radium by biological method

    International Nuclear Information System (INIS)

    Gye-Nam Kim; Seung-Su Kim; Hye-Min Park; Won-Suk Kim; Uk-Ryang Park; Jei-Kwon Moon

    2013-01-01

    Biological method was studied for remediation of soil/concrete contaminated with uranium and radium. Optimum experiment conditions for mixing ratios of penatron and soil, and the pH of soil was obtained through several bioremediations with soil contaminated with uranium and radium. It was found that an optimum mixing ratio of penatron for bioremediation of uranium soil was 1 %. Also, the optimum pH condition for bioremediation of soil contaminated with uranium and radium was 7.5. The removal efficiencies of uranium and radium from higher concentration of soil were rather reduced in comparison with those from lower concentration of soil. Meanwhile, the removal of uranium and radium in concrete by bioremediation is possible but the removal rate from concrete was slower than that from soil. The removal efficiencies of uranium and radium from soil under injection of 1 % penatron at pH 7.5 for 120 days were 81.2 and 81.6 %, respectively, and the removal efficiencies of uranium and radium from concrete under the same condition were 63.0 and 45.2 %, respectively. Beyond 30 days, removal rates of uranium and radium from soil and concrete by bioremediation was very slow. (author)

  6. Implementation of in situ vitrification technology for remediation of Oak Ridge contaminated soil sites: Past results and future plans

    International Nuclear Information System (INIS)

    Tixier, J.S.; Powell, T.D.; Spalding, B.P.; Jacobs, G.K.

    1993-02-01

    In situ vitrification is a thermal treatment technology being developed for remediation of contaminated soils. The process transforms easily leached, contaminated soils into a durable, leach-resistant. vitreous and crystalline monolith. This paper presents the results of the recent highly successful ISV demonstration conducted jointly by PNL and ORNL on a tracer-level quantity of radioactive sludge in a model trench at ORNL. A retention of 90 r in the vitreous and crystalline product of greater than 99.9999% was measured with a reduction in potential environmental mobility of more than two orders of magnitude. The paper also presents the current plans for continued collaboration on a two-setting treatability test on one portion of an old seepage pit at ORNL

  7. Geophysical Monitoring of Hydrocarbon-Contaminated Soils Remediated with a Bioelectrochemical System.

    Science.gov (United States)

    Mao, Deqiang; Lu, Lu; Revil, André; Zuo, Yi; Hinton, John; Ren, Zhiyong Jason

    2016-08-02

    Efficient noninvasive techniques are desired for monitoring the remediation process of contaminated soils. We applied the direct current resistivity technique to image conductivity changes in sandbox experiments where two sandy and clayey soils were initially contaminated with diesel hydrocarbon. The experiments were conducted over a 230 day period. The removal of hydrocarbon was enhanced by a bioelectrochemical system (BES) and the electrical potentials of the BES reactors were also monitored during the course of the experiment. We found that the variation in electrical conductivity shown in the tomograms correlate well with diesel removal from the sandy soil, but this is not the case with the clayey soil. The clayey soil is characterized by a larger specific surface area and therefore a larger surface conductivity. In sandy soil, the removal of the diesel and products from degradation leads to an increase in electrical conductivity during the first 69 days. This is expected since diesel is electrically insulating. For both soils, the activity of BES reactors is moderately imaged by the inverted conductivity tomogram of the reactor. An increase in current production by electrochemically active bacteria activity corresponds to an increase in conductivity of the reactor.

  8. Flare pits wastes remediation by low temperature oxidation

    International Nuclear Information System (INIS)

    Catalan, L. J. L.; Jamaluddin, A. K. M.; Mehta, R.; Moore, R. G.; Okazawa, N.; Ursenbach, M.

    1997-01-01

    The remediation of contaminated soil in oilfield sites, flare pits in particular, is subject to strict environmental regulations. Most current remediation techniques such as biological or thermal treatment are not particularly effective in highly contaminated sites, or effective only at costs that are considered prohibitive. This contribution describes a cost-effective method for the treatment of contaminated soil in-situ. The proposed treatment involves low temperature oxidation which converts the hydrocarbons in the contaminated soil to inert coke. In laboratory studies contaminated soil was oxidized with air at temperatures between 150 degrees C and 170 degrees C for three weeks. After the three week treatment extractable hydrocarbon levels were reduced to less than 0.1 per cent. Bioassays also demonstrated that toxicity associated with hydrocarbons was eliminated. Salts and metals remaining in the soil after treatment were removed by leaching with water. Low temperature oxidation requires no special equipment; it can occur under conditions and with equipment that are readily available in an oilfield setting. 5 refs., 8 tabs., 7 figs

  9. Field trial using bone meal amendments to remediate mine waste derived soil contaminated with zinc, lead and cadmium

    International Nuclear Information System (INIS)

    Sneddon, I.R.; Orueetxebarria, M.; Hodson, M.E.; Schofield, P.F.; Valsami-Jones, E.

    2008-01-01

    Bone meal amendments are being considered as a remediation method for metal-contaminated wastes. In various forms (biogenic, geogenic or synthetic), apatite, the principal mineral constituent of bone, has shown promise as an amendment to remediate metal-contaminated soils via the formation of insoluble phosphates of Pb and possibly other metals. The efficacy of commercially available bovine bone meal in this role was investigated in a field trial at Nenthead, Cumbria with a mine waste derived soil contaminated with Zn, Pb and Cd. Two 5 m 2 plots were set up; the first as a control and the second, a treatment plot where the soil was thoroughly mixed with bone meal to a depth of 50 cm at a soil to amendment ratio of 25:1 by weight. An array of soil solution samplers (Rhizon SMS TM ) were installed in both plots and the soil pore water was collected and analysed for Ca, Cd, Zn and Pb regularly over a period of 2 a. Concurrently with the field trial, a laboratory trial with 800 mm high and 100 mm wide leaching columns was conducted using identical samplers and with soil from the field site. A substantial release of Zn, Pb, Cd and Ca was observed associated with the bone meal treatment. This release was transient in the case of the leaching columns, and showed seasonal variation in the case of the field trial. It is proposed that this effect resulted from metal complexation with organic acids released during breakdown of the bone meal organic fraction and was facilitated by the relatively high soil pH of 7.6-8.0. Even after this transient release effect had subsided or when incinerated bone meal was substituted in order to eliminate the organic fraction, no detectable decrease in dissolved metals was observed and no P was detected in solution, in contrast with an earlier small column laboratory study. It is concluded that due to the relative insolubility of apatite at above-neutral pH, the rate of supply of phosphate to soil solution was insufficient to result in

  10. Study on 3D surfactant assisted electrokinetic remediation of 1,2,4-trichlorobenzene in low permeability soil

    Science.gov (United States)

    Qiao, W.; Ye, S.; Wu, J.

    2014-12-01

    Electrickinetic(EK) is a promising remediation technology because of its capability to remediate soils with low permeability. It has been used for heavy metals and organic pollutant(OPs) contaminated soils. As the most OPs are poor solubility and strong sorption capacity, combined EK technology is usually used, for example, EK combined with surfactants. Numerous combined EK tests are done in one-dimension(1D) column, however, it is proved that there is a big gap between 1D tests and field application. The objectives of this study are to investigate the remediation efficiency and EK behavior of 1,2,4-trichlorobenzene(1,2,4-TCB) contaminated clay enhanced by surfactants in a three-dimension reactor with 28cm length×15cm width×16cm height. 1,2,4-TCB was one of the main contaminants at a field site in Nanjing, China, where the polluted soils are clay. Soil filled in EK cell was divided into six layers in depth, and each layer was divided into six parts in length and three parts in width. There were 108 specimens in total which realized 3D monitoring the effects of EK. Triton X-100(Exp1) and Tween80(Exp2) dissolved in NaCO3/NaHCO3 buffer respectively, were used as the anode purging solution. The distributions of soil pH and water content showed that the buffer was sufficient to neutralize H+ produced at anode and the direction of electroosmotic flow(EOF) remained constant. Exp2 generated a higher EOF than Exp1, but remediation efficiencies were not satisfactory so far. The concentration of 1,2,4-TCB in soil reached a peak and nadir in the normalized distances of 0.75 and 0.9 from cathode after 5 days, respectively. The 1,2,4-TCB concentration in the peak was almost twice as much as the initial concentration. It suggested that 1,2,4-TCB was desorbed from soil by surfactants and was transported from anode to cathode by EOF, which proved the capability of EK with surfactants to move 1,2,4-TCB in clay. The concentration of 1,2,4-TCB in the normalized distances of 0

  11. Rhizobia and their bio-partners as novel drivers for functional remediation in contaminated soils.

    Science.gov (United States)

    Teng, Ying; Wang, Xiaomi; Li, Lina; Li, Zhengao; Luo, Yongming

    2015-01-01

    Environmental pollutants have received considerable attention due to their serious effects on human health. There are physical, chemical, and biological means to remediate pollution; among them, bioremediation has become increasingly popular. The nitrogen-fixing rhizobia are widely distributed in the soil and root ecosystems and can increase legume growth and production by supplying nitrogen, resulting in the reduced need for fertilizer applications. Rhizobia also possess the biochemical and ecological capacity to degrade organic pollutants and are resistant to heavy metals, making them useful for rehabilitating contaminated soils. Moreover, rhizobia stimulate the survival and action of other biodegrading bacteria, thereby lowering the concentration of pollutants. The synergistic action of multiple rhizobial strains enhances both plant growth and the availability of pollutants ranging from heavy metals to persistent organic pollutants. Because phytoremediation has some restrictions, the beneficial interaction between plants and rhizobia provides a promising option for remediation. This review describes recent advances in the exploitation of rhizobia for the rehabilitation of contaminated soil and the biochemical and molecular mechanisms involved, thereby promoting further development of this novel bioremediation strategy into a widely accepted technique.

  12. Electrokinetic-Fenton remediation of organochlorine pesticides from historically polluted soil.

    Science.gov (United States)

    Ni, Maofei; Tian, Shulei; Huang, Qifei; Yang, Yanmei

    2018-04-01

    Soil contamination by persistent organic pollutants (POPs) poses a great threat to historically polluted soil worldwide. In this study, soils were characterized, and organochlorine pesticides contained in the soils were identified and quantified. Individual electrokinetic (IE), EK-Fenton-coupled technologies (EF), and enhanced EK-Fenton treatment (E-1, E-2, and E-3) were applied to remediate soils contaminated with hexachloro-cyclohexane soprocide (HCH) and dichloro-diphenyl-trichloroethane (DDT). Variation of pH, electrical conductivity, and electroosmotic flow was evaluated during the EK-Fenton process. The IE treatment showed low removal efficiency for HCHs (30.5%) and DDTs (25.9%). In the EF treatment, the highest removal level (60.9%) was obtained for α-HCH, whereas P,P-DDT was the lowest (40.0%). Low solubility of pollutants impeded the HCH and DDT removal. After enhanced EK-Fenton treatment, final removal of pollutants decreased as follows: β-HCH (82.6%) > γ-HCH (81.6%) > α-HCH (81.2%) > δ-HCH (80.0%) > P,P-DDD (73.8%) > P,P-DDE (73.1%) > P,P-DDT (72.6%) > O,P-DDT (71.5%). The results demonstrate that EK-Fenton is a promising technology for POP removal in historically polluted soil.

  13. Potential of oil palm empty fruit bunch ash for remediation of crude ...

    African Journals Online (AJOL)

    The potential of oil palm empty fruit bunch ash for remediation of crude oil polluted soil was investigated. Three levels (100 g, 200 g and 300 g) of ash treatments in 2 kg of soil were set up alongside a control (nil ash) after pollution with100 ml of crude oil. Composite soil samples were collected and analyzed at intervals of ...

  14. A review on heavy metal contamination in the soil worldwide: Situation, impact and remediation techniques

    Directory of Open Access Journals (Sweden)

    Chao Su

    2014-06-01

    Full Text Available Heavy metals in the soil refers to some significant heavy metals of biological toxicity, including mercury (Hg, cadmium (Cd, lead (Pb, chromium (Cr, and arsenic (As, etc. With the development of the global economy, both type and content of heavy metals in the soil caused by human activities have gradually increased in recent years, which have resulted in serious environment deterioration. In present study we compared and analyzed soil contamination of heavy metals in various cities/countries, and reviewed background, impact and remediation methods of soil heavy metal contamination worldwide.

  15. Stimulation of biological N2-fixation to accelerate the microbial remediation of soil contaminated by petroleum hydrocarbons

    International Nuclear Information System (INIS)

    Tereshenko, N.N.; Lushnikov, S.V.

    2005-01-01

    All remediation projects are comprised at least in accelerating the processes of the self-cleaning and self-restoration of biocenose which is led to increasing the functional activity of hydrocarbon-oxidizing microflora (HOM). Some of experts are carefully relate to introducing the commercial cultures of active hydrocarbon-consuming microbes into soils. They are afraid of unpredictable behavior of the cultures in soils. That why the stimulation of metabolic activity of indigenous soil microflora seems to be most preferable. In fact, contamination of soil with low nitrogen capacity by oil spills leads to significant deficient of nitrogen for HOM. Nitrogen content limits the soil self-restoration. Inorganic nitrogen fertilizers are supplied to recover the balance. The study of the microbial destruction of petroleum-hydrocarbons in association with biochemical transformation of nitrogen was carried out in lab and field experiments during 2000-2004. Study showed the activity of HOM correlates with rate of microbial fixing atmospheric nitrogen. Activity of biological N 2 -fixation significantly depends on supplying fertilizers (dose, date and kind). General practice of remediation of hydrocarbon-contaminated soils applies high initial doses of nitrogen-fertilizers (0.5-1 t per ha). Such practice leads to inhibition of N 2 -fixation processes, decreasing rate of oil destruction and loosing nitrogen due to activation of microbial denitrification. In opposition to that, the fractioned and advanced supplying mineral nitrogen fertilizers with aluminosilicate is the cost-effective approach to remediation of hydrocarbon-contaminated soils. Field experiments showed that the approach allows to increase efficiency of treatment up to 70-75% and to decrease operational expenses 2-3 times at least. (authors)

  16. The potential impact on the biodegradation of organic pollutants from composting technology for soil remediation.

    Science.gov (United States)

    Ren, Xiaoya; Zeng, Guangming; Tang, Lin; Wang, Jingjing; Wan, Jia; Wang, Jiajia; Deng, Yaocheng; Liu, Yani; Peng, Bo

    2018-02-01

    Large numbers of organic pollutants (OPs), such as polycyclic aromatic hydrocarbons, pesticides and petroleum, are discharged into soil, posing a huge threat to natural environment. Traditional chemical and physical remediation technologies are either incompetent or expensive, and may cause secondary pollution. The technology of soil composting or use of compost as soil amendment can utilize quantities of active microbes to degrade OPs with the help of available nutrients in the compost matrix. It is highly cost-effective for soil remediation. On the one hand, compost incorporated into contaminated soil is capable of increasing the organic matter content, which improves the soil environment and stimulates the metabolically activity of microbial community. On the other hand, the organic matter in composts would increase the adsorption of OPs and affect their bioavailability, leading to decreased fraction available for microorganism-mediated degradation. Some advanced instrumental analytical approaches developed in recent years may be adopted to expound this process. Therefore, the study on bioavailability of OPs in soil is extremely important for the application of composting technology. This work will discuss the changes of physical and chemical properties of contaminated soils and the bioavailability of OPs by the adsorption of composting matrix. The characteristics of OPs, types and compositions of compost amendments, soil/compost ratio and compost distribution influence the bioavailability of OPs. In addition, the impact of composting factors (composting temperature, co-substrates and exogenous microorganisms) on the removal and bioavailability of OPs is also studied. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Enhancement Solution to Improve Remediation of Soil Contaminated with Lead by Electrical Field

    Directory of Open Access Journals (Sweden)

    Ayad Abd Al-hamza Faisal

    2015-11-01

    Full Text Available A laboratory investigation of six different tests were conducted on silty clay soil spiked with lead in concentrations of 1500 mg/kg. A constant DC voltage gradient of 1 V/cm was applied for all these tests with duration of 7 days remediation process for each test. Different purging solutions and addition configurations, i.e. injection wells, were investigated experimentally to enhance the removal of lead from Iraqi soil during electro-kinetic remediation process. The experimental results showed that the overall removal efficiency of lead for tests conducted with distilled water, 0.1 M acetic acid, 0.2 M EDTA and 1 M ammonium citrate as the purging solutions were equal to 18 %, 37 %, 42 %, and 29 %, respectively. However, introducing the injection wells as another enhancement technique into the tests used the same purging solutions mentioned above which have vital role in increasing the removal efficiency up to 59 %.

  18. Control of electrode processes in electrokinetic soil remediation

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, M.; Marb, C. [Bavarian State Office for Environmental Protection, Waste Technology Centre, Augsburg (Germany)

    2001-07-01

    Technical control of electrode processes induced by water electrolysis is crucial for the effectiveness of electrokinetic soil remediation. A calculation method for the quantification of electrolysis products is derived and its validity by the consumption of neutralizing agents verified. Steel rods used as sacrificial anodes instead of inert materials cannot counteract the acidification of the anolyte due to the acidic property of Fe-cations released as oxidation products. An an alternative to ordinary porous well materials a tubular cation exchange membrane was used as a cathode well. Thereby the migration of anions stemming from the catholyte neutralisation was hampered and no loss in the electric field strength occured. (orig.)

  19. Petroleum hydrocarbon remediation in frozen soil using a meat and bonemeal biochar plus fertilizer.

    Science.gov (United States)

    Karppinen, Erin M; Stewart, Katherine J; Farrell, Richard E; Siciliano, Steven D

    2017-04-01

    Petroleum hydrocarbon (PHC) degradation slows significantly during the winter which substantially increases the time it takes to remediate soil in Arctic landfarms. The aim of this laboratory trial was to assess the potential of a meat and bonemeal (MBM) biochar to stimulate PHC degradation in contaminated soil collected from Iqaluit, Canada. Over 90 days, 3% (w/w) MBM biochar significantly increased F3- (equivalent nC 16 -C 34 ) PHC degradation rate constants (k) in frozen soils when compared to the fertilizer (urea and monoammonium phosphate) control. Taking into consideration extensive variability within treatments and negative k values, this difference may not reflect significant remediation. Decreasing C 17 /Pr and C 18 /Ph ratios in the frozen soil suggest that this reduction is a result of microbial degradation rather than volatilization. Amendment type and application rate affected the immediate abiotic losses of F2 and F3-PHC in sterile soils, with the greatest losses occurring in compost-amended treatments in the first 24 h. In frozen soils, MBM biochar was found to increase liquid water content (θ liquid ) but not nutrient supply rates. Under frozen but not thawed conditions, genes for aromatic (C2,3O and nahAc) but not aliphatic (alkB) PHC degradation increased over time in both biochar-amended and control treatments but total viable PHC-degrading populations only increased in biochar-amended soils. Based on these results, it is possible that PHC degradation in biochar-amended soils is active and even enhanced under frozen conditions, but further investigation is required. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Remediation of asbestos in soil

    International Nuclear Information System (INIS)

    McFarland, Ross; Dangerfield, David

    2012-01-01

    The former Patea Freezing Works in the Tarankai region of New Zealand began as a canning plant and tallow factory in the late 1800s. Freezing technology was introduced in 1904 and was in continuous operation until 1982. Some of the structures were destroyed by fire in 2008, leaving metal, ash and asbestos. Fragments of Asbestos Containing Material (ACM) were blown over the local town and a large area of the site. A remedial strategy was developed by Aecom and they also provided validation services. . The preferred option was to remove the top layer of ACM impacted soil and place it in an engineered containment cell on site. However this process could not be used due to local cultural objections, and the 'dig and dump' option was adopted. The Western Australian Department of Health (DOH) Guidelines, May 2009, were used in collaboration with local district New Zealand Councils. Monitoring wells were installed, however the monitoring program is not yet underway as the revegetation program is not complete.

  1. Integrated phytobial remediation for sustainable management of arsenic in soil and water.

    Science.gov (United States)

    Roy, Madhumita; Giri, Ashok K; Dutta, Sourav; Mukherjee, Pritam

    2015-02-01

    Arsenic (As), cited as the most hazardous substance by the U.S. Agency for Toxic Substance and Disease Registry (ATSDR, 2005), is an ubiquitous metalloid which when ingested for prolonged periods cause extensive health effects leading to ultimate untimely death. Plants and microbes can help mitigate soil and groundwater As problem since they have evolved elaborate detoxification machineries against this toxic metalloid as a result of their coexistence with this since the origin of life on earth. Utilization of the phytoremediation and bioremediation potential of the plants and microbes, respectively, is now regarded as two innovative tools that encompass biology, geology, biotechnology and allied sciences with cutting edge applications for sustainable mitigation of As epidemic. Discovery of As hyperaccumulating plants that uptake and concentrate large amounts of this toxic metalloid in their shoots or roots offered new hope to As phytoremediation, solar power based nature's own green remediation. This review focuses on how phytoremediation and bioremediation can be merged together to form an integrated phytobial remediation which could synergistically achieve the goal of large scale removal of As from soil, sediment and groundwater and overcome the drawbacks of the either processes alone. The review also points to the feasibility of the introduction of transgenic plants and microbes that bring new hope for more efficient treatment of As. The review identifies one critical research gap on the importance of remediation of As contaminated groundwater not only for drinking purpose but also for irrigation purpose and stresses that more research should be conducted on the use of constructed wetland, one of the most suitable areas of application of phytobial remediation. Finally the review has narrowed down on different phytoinvestigation and phytodisposal methods, which constitute the most essential and the most difficult part of pilot scale and field scale applications

  2. Electrokinetic delivery of persulfate to remediate PCBs polluted soils: effect of injection spot.

    Science.gov (United States)

    Fan, Guangping; Cang, Long; Fang, Guodong; Qin, Wenxiu; Ge, Liqiang; Zhou, Dongmei

    2014-12-01

    Persulfate-based in situ chemical oxidation (ISCO) is a promising technique for the remediation of organic compounds contaminated soils. Electrokinetics (EK) provides an alternative method to deliver oxidants into the target zones especially in low permeable-soil. In this study, the flexibility of delivering persulfate by EK to remediate polychlorinated biphenyls (PCBs) polluted soil was investigated. 20% (w/w) of persulfate was injected at the anode, cathode and both electrodes to examine its transport behaviors under electrical field, and the effect of field inversion process was also evaluated. The results showed that high dosage of persulfate could be delivered into S4 section (near cathode) by electroosmosis when persulfate was injected from anode, 30.8% of PCBs was removed from the soil, and the formed hydroxyl precipitation near the cathode during EK process impeded the transportation of persulfate. In contrast, only 18.9% of PCBs was removed with the injection of persulfate from cathode, although the breakthrough of persulfate into the anode reservoir was observed. These results indicated that the electroosmotic flow is more effective for the transportation of persulfate into soil. The addition of persulfate from both electrodes did not significantly facilitate the PCBs oxidation as well as the treatment of electrical field reversion, the reinforced negative depolarization function occurring in the cathode at high current consumed most of the oxidant. Furthermore, it was found that strong acid condition near the anode favored the oxidation of PCBs by persulfate and the degradation of PCBs was in consistent with the oxidation of Soil TOC in EK/persulfate system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction

    Energy Technology Data Exchange (ETDEWEB)

    Crean, Daniel E. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield (United Kingdom); Centre for Radiochemistry Research, School of Chemistry, The University of Manchester (United Kingdom); Livens, Francis R.; Sajih, Mustafa [Centre for Radiochemistry Research, School of Chemistry, The University of Manchester (United Kingdom); Stennett, Martin C. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield (United Kingdom); Grolimund, Daniel; Borca, Camelia N. [Swiss Light Source, Paul Scherrer Institute, Villigen (Switzerland); Hyatt, Neil C., E-mail: n.c.hyatt@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield (United Kingdom)

    2013-12-15

    Highlights: • Batch leaching was examined to remediate soils contaminated with munitions depleted uranium. • Site specific maximum extraction was 42–50% total U in single batch with NH{sub 4}HCO{sub 3}. • Analysis of residues revealed partial leaching and secondary carbonate phases. • Sequential batch leaching alternating between NH{sub 4}HCO{sub 3} and citric acid was designed. • Site specific extraction was increased to 68–87% total U in three batch steps. -- Abstract: Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42–50% total DU extracted), citric acid (30–42% total DU) and sulphuric acid (13–19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68–87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents.

  4. Plant remediation of soil contaminated with 137Cs

    International Nuclear Information System (INIS)

    Yang Juncheng; Zhang Jianfeng; Zhu Yongyi; Chen Jingjie; Mei Yong; Jiang Huimin

    2005-01-01

    A pot experiment was conducted to evaluate the bio-remediation of soils contaminated with 137 Cs. The selected plants are Cucurbita moschata Duchesne, Brassica chinensis L, Chloris virgata, Beta oulgaris L. Hongye, Beta oulgaris L. Dongshengye and Beta oulgaris L. The soils samples were taken from the paddy field, 2 km from the Dayawan nuclear power plant and Qinshan nuclear power plant, respectively, and cinnamon soil from the cultivated land in Beijing. The results show that all the employed species of plant have a higher accumulation to 137 Cs with the increased grade of the radioactivity of 137 Cs. A good correlation exist with the coefficient (r 2 ) of 0.9989. When the contaminated radioactivity of 137 Cs is in the same level the uptake of Cucurbita moschata Duchesne, Brassica chinensis L. and Chloris virgata increased with the decrease of pH value ranged 5.22-7.69. The ability of bioremediation in the orders were Chloris virgata, Brassica chinensis L., Beta oulgaris L. Hongye, Cucurbita moschata Duchesne, Beta oulgaris L. and Beta oulgaris L. Dongshengye, according to the comprehensive evaluation of transfer factor, specific activity of plant in dry weight of biomass and total absorption of 137 Cs by the individual plant in the same area. (authors)

  5. Feasibility of Using Phytoextraction to Remediate a Compost-Based Soil Contaminated with Cadmium.

    Science.gov (United States)

    Parisien, Michele A; Rutter, Allison; Zeeb, Barbara A

    2015-01-01

    Greenhouse and in-situ field experiments were used to determine the potential for phytoextraction to remediate soil contaminated with Cd from municipal solid waste (MSW) and sewage sludge (SS) compost application at a Peterborough (Canada) site. For the greenhouse experiment, one native (Chenopodium album) and three naturalized (Poa compressa, Brassica juncea, Helianthus annuus) plant species were planted in soil containing no detectable Cd (phytoextraction is therefore not feasible at this site. Though low Cd bioavailability has negative implications for Cd phytoextraction from MSW/SS compost-based soils, it may limit receptor exposure to Cd sufficiently to eliminate the potential for risk at this site.

  6. Environmental materials for remediation of soils contaminated with lead and cadmium using maize (Zea mays L.) growth as a bioindicator.

    Science.gov (United States)

    Shi, Yu; Huang, Zhanbin; Liu, Xiujie; Imran, Suheryani; Peng, Licheng; Dai, Rongji; Deng, Yulin

    2016-04-01

    Heavy metal pollution is a severe environmental problem. Remediation of contaminated soils can be accomplished using environmental materials that are low cost and environmentally friendly. We evaluated the individual and combination effects of humic acid (HA), super absorbent polymer (SAP), zeolite (ZE), and fly ash composites (FC) on immobilization of lead (Pb) and cadmium (Cd) in contaminated soils. We also investigated long-term practical approaches for remediation of heavy metal pollution in soil. The biochemical and morphological properties of maize (Zea mays L.) were selected as biomarkers to assess the effects of environmental materials on heavy metal immobilization. The results showed that addition of test materials to soil effectively reduced heavy metal accumulation in maize foliage, improving chlorophyll levels, plant growth, and antioxidant enzyme activity. The test materials reduced heavy metal injury to maize throughout the growth period. A synergistic effect from combinations of different materials on immobilization of Pb and Cd was determined based on the reduction of morphological and biochemical injuries to maize. The combination of zeolite and humic acid was especially effective. Treatment with a combination of HA + SAP + ZE + FC was superior for remediation of soils contaminated with high levels of Pb and Cd.

  7. LCA of Soil and Groundwater Remediation

    DEFF Research Database (Denmark)

    Søndergaard, Gitte Lemming; Owsianiak, Mikolaj

    2018-01-01

    Today, there is increasing interest in applying LCA to support decision-makers in contaminated site management. In this chapter, we introduce remediation technologies and associated environmental impacts, present an overview of literature findings on LCA applied to remediation technologies...... and present methodological issues to consider when conducting LCAs within the area. Within the field of contaminated site remediation , a terminology distinguishing three types of environmental impacts: primary, secondary and tertiary, is often applied. Primary impacts are the site-related impacts due...... and efficiency of remediation, which are important for assessment or primary impacts; (ii) robust assessment of primary impacts using site-specific fate and exposure models; (iii) weighting of primary and secondary (or tertiary) impacts to evaluate trade-offs between life cycle impacts from remediation...

  8. The application of in situ air sparging as an innovative soils and ground water remediation technology

    International Nuclear Information System (INIS)

    Marley, M.C.; Hazebrouck, D.J.; Walsh, M.T.

    1992-01-01

    Vapor extraction (soil venting) has been demonstrated to be a successful and cost-effective remediation technology for removing VOCs from the vadose (unsaturated) zone. However, in many cases, seasonal water table fluctuations, drawdown associated with pump-and-treat remediation techniques, and spills involving dense, non-aqueous phase liquids (DNAPLS) create contaminated soil below the water table. Vapor extraction alone is not considered to be an optimal remediation technology to address this type of contamination. An innovative approach to saturated zone remediation is the use of sparging (injection) wells to inject a hydrocarbon-free gaseous medium (typically air) into the saturated zone below the areas of contamination. The contaminants dissolved in the ground water and sorbed onto soil particles partition into the advective air phase, effectively simulating an in situ air-stripping system. The stripped contaminants are transported in the gas phase to the vadose zone, within the radius of influence of a vapor extraction and vapor treatment system. In situ air sparging is a complex multifluid phase process, which has been applied successfully in Europe since the mid-1980s. To date, site-specific pilot tests have been used to design air-sparging systems. Research is currently underway to develop better engineering design methodologies for the process. Major design parameters to be considered include contaminant type, gas injection pressures and flow rates, site geology, bubble size, injection interval (areal and vertical) and the equipment specifications. Correct design and operation of this technology has been demonstrated to achieve ground water cleanup of VOC contamination to low part-per-billion levels

  9. Integrated Nanozero Valent Iron and Biosurfactant-Aided Remediation of PCB-Contaminated Soil

    Directory of Open Access Journals (Sweden)

    He Zhang

    2016-01-01

    Full Text Available Polychlorobiphenyls (PCBs have been identified as environmental hazards for years. Due to historical issues, a considerable amount of PCBs was released deep underground in Canada. In this research, a nanoscale zero valent iron- (nZVI- aided dechlorination followed by biosurfactant enhanced soil washing method was developed to remove PCBs from soil. During nZVI-aided dechlorination, the effects of nZVI dosage, initial pH level, and temperature were evaluated, respectively. Five levels of nZVI dosage and two levels of initial pH were experimented to evaluate the PCB dechlorination rate. Additionally, the temperature changes could positively influence the dechlorination process. In soil washing, the presence of nanoiron particles played a key role in PCB removal. The crude biosurfactant was produced using a bacterial stain isolated from the Atlantic Ocean and was applied for soil washing. The study has led to a promising technology for PCB-contaminated soil remediation.

  10. APPLICATION OF FENTON’S REAGENT ON REMEDIATION OF POLYCYCLIC AROMATIC HYDROCARBONs (PAHs IN SPIKED SOIL

    Directory of Open Access Journals (Sweden)

    Nursiah La Nafie

    2010-06-01

    Full Text Available Problem associated with Polycyclic Aromatic Hydrocarbons (PAHs contaminated site in environmental media have received increasing attention. To resolve such problems, innovative in situ methods are urgently required. This work investigated the feasibility of using Fenton's Reagent to remediate PAHs in spiked soil. PAHs were spiked into soil to simulate contaminated soil. Fenton's Reagent (H2O2 + Fe2+ and surfactant were very efficient in destruction of PAHs including naphthalene, anthracene, fluoranthene, pyrene, and benzo(apyrene from spiked soil. It was indicated by the fact that more than 96% of PAHs were degraded in the solution and the spiked soil.   Keywords: Environmental, Fenton's Reagent, Polycyclic Aromatic Hydrocarbons, and Spiked soil.

  11. [Remediation Pb, Cd contaminated soil in lead-zinc mining areas by hydroxyapatite and potassium chloride composites].

    Science.gov (United States)

    Wang, Li; Li, Yong-Hua; Ji, Yan-Fang; Yang, Lin-Sheng; Li, Hai-Rong; Zhang, Xiu-Wu; Yu, Jiang-Ping

    2011-07-01

    The composite agents containing potassium chloride (KCl) and Hydroxyapatite (HA) were used to remediate the lead and cadmium contaminated soil in Fenghuang lead-zinc mining-smelting areas, Hunan province. The objective of this study was to identify and evaluate the influence of Cl- to the fixing efficiency of Pb and Cd by HA. Two types of contaminated soil (HF-1, HF-2) were chosen and forty treatments were set by five different Hydroxyapatite (HA) dosages and four different Cl- dosages. The toxicity characteristic leaching procedure (TCLP) was used to evaluate the results. It showed that HA could efficiently fix the Pb and Cd from TCLP form. The maximum Pb-fixing efficiency and Cd-fixing efficiency of two types of soil were 83.3%, 97.27% and 35.96%, 57.82% when the HA: Pb: KCl molar ratio was 8: 1: 2. Compared to the fixing efficiency without KCl, KCl at the KCl: Pb molar ratio of 2 improved Pb-fixing efficiency and Cd-fixing efficiency by 6.26%, 0.33% and 7.74%, 0.83% respectively when the HA: Pb molar ratio was 8. Generally, Cl- can improve the Pb/Cd-fixing efficiency in heavy metal contaminated soil by Hydroxyapatite.

  12. Cultural and wild plant species as bio indicators and phyto-remedies of PHC contaminated soils in Russia

    International Nuclear Information System (INIS)

    Breus, I.; Larionova, N.; Semenova, E.; Breus, V.

    2005-01-01

    The biological indicators are widely used along with the chemical and physical soil characteristics for the ecological risk assessment for soils during and after anthropogenic impacts. In many cases it often happens that only biological indicators are capable of establishing the physiological activity of contaminant complex in soil and of revealing the critical levels of soil contamination. Bio-testing is often used to determine the toxicity of various environmental objects - soils, waters, sediments and wastes. Firstly bio-testing demands the selection of testable biological organisms adequate to studying objects. The test objects must be representative for a given contaminated ecosystem community which is influenced by toxicants. So one can obtain data adequate to the real situation and also minimise the mistakes during the extrapolation of data obtained in bio-testing. Among bio-testing methods the methods of soil toxicity determination using high plants gained wide distribution. And moreover, if such plants are relatively tolerant to soil contamination and can accumulate sufficient plant biomass, it is possible to expect their phyto-remediation effect, which can be realized by different mechanisms. But the experimental investigations of the plant use for soil remediation in Russia are now still under development. The aims of this work were: i) the determination and selection of informative bio-indicative parameters could be used for evaluation of PHC (petroleum hydrocarbons) - soil contamination levels; ii) the choose of test plants based on these values; and iii) the revelation of the possible phyto-remediation effects in soil contaminated with PHC.In laboratory experiments the phyto-toxicity of soil contaminated with PHC was evaluated in relation to 35 plant species and sorts traditional and non-traditional for Russia and cultivated for fodder green biomass purposes, and also for some wild plant species. The following parameters were determined in the

  13. Cultural and wild plant species as bio indicators and phyto-remedies of PHC contaminated soils in Russia

    Energy Technology Data Exchange (ETDEWEB)

    Breus, I.; Larionova, N.; Semenova, E.; Breus, V. [Kazan State Univ., Dept. of Geography and Geoecology (Russian Federation)

    2005-07-01

    The biological indicators are widely used along with the chemical and physical soil characteristics for the ecological risk assessment for soils during and after anthropogenic impacts. In many cases it often happens that only biological indicators are capable of establishing the physiological activity of contaminant complex in soil and of revealing the critical levels of soil contamination. Bio-testing is often used to determine the toxicity of various environmental objects - soils, waters, sediments and wastes. Firstly bio-testing demands the selection of testable biological organisms adequate to studying objects. The test objects must be representative for a given contaminated ecosystem community which is influenced by toxicants. So one can obtain data adequate to the real situation and also minimise the mistakes during the extrapolation of data obtained in bio-testing. Among bio-testing methods the methods of soil toxicity determination using high plants gained wide distribution. And moreover, if such plants are relatively tolerant to soil contamination and can accumulate sufficient plant biomass, it is possible to expect their phyto-remediation effect, which can be realized by different mechanisms. But the experimental investigations of the plant use for soil remediation in Russia are now still under development. The aims of this work were: i) the determination and selection of informative bio-indicative parameters could be used for evaluation of PHC (petroleum hydrocarbons) - soil contamination levels; ii) the choose of test plants based on these values; and iii) the revelation of the possible phyto-remediation effects in soil contaminated with PHC.In laboratory experiments the phyto-toxicity of soil contaminated with PHC was evaluated in relation to 35 plant species and sorts traditional and non-traditional for Russia and cultivated for fodder green biomass purposes, and also for some wild plant species. The following parameters were determined in the

  14. DOE In Situ Remediation Integrated Program

    International Nuclear Information System (INIS)

    Yow, J.L. Jr.

    1993-01-01

    The In Situ Remediation Integrated Program (ISRP) supports and manages a balanced portfolio of applied research and development activities in support of DOE environmental restoration and waste management needs. ISRP technologies are being developed in four areas: containment, chemical and physical treatment, in situ bioremediation, and in situ manipulation (including electrokinetics). the focus of containment is to provide mechanisms to stop contaminant migration through the subsurface. In situ bioremediation and chemical and physical treatment both aim to destroy or eliminate contaminants in groundwater and soils. In situ manipulation (ISM) provides mechanisms to access contaminants or introduce treatment agents into the soil, and includes other technologies necessary to support the implementation of ISR methods. Descriptions of each major program area are provided to set the technical context of the ISM subprogram. Typical ISM needs for major areas of in situ remediation research and development are identified

  15. Effect of Wetting Agents and Approaching Anodes on Lead Migration in Electrokinetic Soil Remediation

    OpenAIRE

    Ng, Yee-Sern; Gupta, Bhaskar Sen; Hashim, Mohd Ali

    2015-01-01

    This is the presentation slides for my conference paper "Effect of Wetting Agents and Approaching Anodes on Lead Migration in Electrokinetic Soil Remediation", which was presented in 5th International Conference on Chemical Engineering and Applications, Taipei on 27 August 2014.

  16. Remediation of lead, cadmium and uranium contaminated water and soil by apatite amendment

    International Nuclear Information System (INIS)

    Raicevic, S.; Plecas, I.; Kaludjerovic, T.

    2002-01-01

    During the past years as a consequence of war and some accidents in neighboring countries large areas in Serbia were contaminated by toxic heavy metals, including lead, cadmium and uranium. For example, the concentrations of Pb, Cd, Cu and Cr have been doubled above the allowed maximum value in the Romanian part of the Danube while sediments near the border in Bulgaria have higher concentrations of Pb 3 times, Cu 1400 times and Cd 30 times more than the average long-standing levels. Furthermore, an estimated 10 tons of depleted uranium (DU) was spread mainly throughout the territory of Kosovo. This contamination is a potential source of different chronic diseases including malignant diseases and represents a long-term threat for the population living in the affected areas. For this reason, remediation of contaminated sites represents an urgent need and priority. The standard remediation procedure which includes soil removal, treatment (washing, chelating), conditioning etc. is costly, disruptive and not sustainable. This study was carried out to evaluate apatite from the Lisina deposit as soil amendment for in situ stabilization of toxic heavy metals. Preliminary theoretical and experimentally results presented here point out this natural apatite as an ecological, nontoxic material which can be used for efficient and cost-effective remediation of large areas contaminated with Pb, Cd and U. (author)

  17. Remediation using trace element humate surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Riddle, Catherine Lynn; Taylor, Steven Cheney; Bruhn, Debra Fox

    2016-08-30

    A method of remediation at a remediation site having one or more undesirable conditions in which one or more soil characteristics, preferably soil pH and/or elemental concentrations, are measured at a remediation site. A trace element humate surfactant composition is prepared comprising a humate solution, element solution and at least one surfactant. The prepared trace element humate surfactant composition is then dispensed onto the remediation site whereby the trace element humate surfactant composition will reduce the amount of undesirable compounds by promoting growth of native species activity. By promoting native species activity, remediation occurs quickly and environmental impact is minimal.

  18. A study on the assessment of treatment technologies for efficient remediation of radioactively-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jong Soon; Shin, Seung Su; KIm, Sun Il [Chosun University, Gwangju (Korea, Republic of)

    2016-09-15

    Soil can be contaminated by radioactive materials due to nuclide leakage following unexpected situations during the decommissioning of a nuclear power plant. Soil decontamination is necessary if contaminated land is to be reused for housing or industry. The present study classifies various soil remediation technologies into biological, physics/chemical and thermal treatment and analyzes their principles and treatment materials. Among these methods, this study selects technologies and categorizes the economics, applicability and technical characteristics of each technology into three levels of high, medium and low by weighting the various factors. Based on this analysis, the most applicable soil decontamination technology was identified.

  19. Characterization and remediation of highly radioactive contaminated soil at Hanford

    International Nuclear Information System (INIS)

    Buckmaster, M.A.; Erickson, J.K.

    1993-09-01

    The Hanford Site, Richland, Washington, contains over 1,500 identified waste sites and numerous groundwater plumes that will be characterized and remediated over the next 30 years. As a result of the Hanford Federal Facility Agreement and Consent Order, the US Department of Energy (DOE) has initiated a remedial investigation/feasibility study (RI/FS) at the 200-BP-1 operable unit. The 200-BP-1 RI/FS is the first Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) investigation on the Hanford Site that involves highly radioactive and chemically contaminated soils. The initial phase of site characterization was designed to assess the nature and extent of contamination associated with the source waste sites within the 200-BP-1 operable unit. Characterization activities consisted of drilling and sampling, chemical and physical analysis of samples, and development of a conceptual vadose zone model. These data were then used. to develop remedial alternatives during the FS evaluation. The preferred alternative resulting from the RI/FS process for the 200-BP-1 operable unit is to construct a surface isolation barrier. The multi-layered earthen barrier will be designed to prevent migration of contaminants resulting from water infiltration, biointrusion, and wind and water erosion

  20. APPLICATION OF THE LASAGNA(trademark) SOIL REMEDIATION TECHNOLOGY AT THE DOE PADUCAH GASEOUS DIFFUSION PLANT

    International Nuclear Information System (INIS)

    Swift, Barry D.; Tarantino, Joseph J. P. E.

    2003-01-01

    The Paducah Gaseous Diffusion Plant (PGDP), owned by the Department of Energy (DOE), has been enriching uranium since the early 1950s. The enrichment process involves electrical and mechanical components that require periodic cleaning. The primary cleaning agent was trichloroethene (TCE) until the late 1980s. Historical documentation indicates that a mixture of TCE and dry ice were used at PGDP for testing the integrity of steel cylinders, which stored depleted uranium. TCE and dry ice were contained in a below-ground pit and used during the integrity testing. TCE seeped from the pit and contaminated the surrounding soil. The Lasagna(trademark) technology was identified in the Record of Decision (ROD) as the selected alternative for remediation of the cylinder testing site. A public-private consortium formed in 1992 (including DOE, the U.S. Environmental Protection Agency, and the Kentucky Department for Environmental Protection, Monsanto, DuPont, and General Electric) developed the Lasagna(trademark) technology. This innovative technology employs electrokinetics to remediate soil contaminated with organics and is especially suited to sites with low permeability soils. This technology uses direct current to move water through the soil faster and more uniformly than hydraulic methods. Electrokinetics moves contaminants in soil pore water through treatment zones comprised of iron filings, where the contaminants are decomposed to basic chemical compounds such as ethane. After three years of development in the laboratory, the consortium field tested the Lasagna(trademark) process in several phases. CDM installed and operated Phase I, the trial installation and field test of a 150-square-foot area selected for a 120-day run in 1995. Approximately 98 percent of the TCE was removed. CDM then installed and operated the next phase (IIa), a year-long test on a 600-square-foot site. Completed in July 1997, this test removed 75 percent of the total volume of TCE down to a

  1. Bioventing feasibility study of low permeability soils for remediation of petroleum contamination

    International Nuclear Information System (INIS)

    Brackney, K.M.

    1994-01-01

    A site characterization of leaking underground gasoline and diesel storage tanks at the University of Idaho, West Farm Operations Center, identified approximately 800 cubic yards of petroleum-contaminated soil exceedingly regulatory action limits of 100 ppm TPH. Bioventing, a combination of in situ soil vapor extraction and microbial degradation, was selected as a remedial alternative on the basis of the presumably unsaturated paleo-soil with a 45-foot depth to groundwater, and a microbial study which concluded that indigenous petroleum-degrading microorganisms existed throughout the contamination. Soil vapor extraction tests were conducted by applying a 60-inch water column vacuum to a soil vapor extraction well and monitoring pneumatic pressure drawdown in 12 adjacent pneumatic piezometers and vertically distributed piezometer clusters. Pressure drawdown vs time data plots indicated that air permeability is inadequate everywhere at the site except at 20 feet below ground surface. Low soil permeability creates conditions for a perched water table that was documented during the investigation, resulting in unsatisfactory conditions for in situ bioventing. 8 refs., 14 figs

  2. Integrated remediation of soil and groundwater

    International Nuclear Information System (INIS)

    Dykes, R.S.; Howles, A.C.

    1992-01-01

    Remediation of sites contaminated with petroleum hydrocarbons and other organic chemicals frequently focuses on a single phase of the chemical in question. This paper describes an integrated approach to remediation involving selection of complimentary technologies designed to create a remedial system which achieves cleanup goals in affected media in the shortest possible time consistent with overall environmental protection

  3. Full-scale testing and early production results from horizontal air sparging and soil vapor extraction wells remediating jet fuel in soil and groundwater at JFK International Airport, New York

    International Nuclear Information System (INIS)

    Roth, R.J.; Bianco, P.; Pressly, N.C.

    1996-01-01

    Jet fuel contaminated soil and groundwater contaminated at the International Arrivals Building (IAB) of the JFK International Airport in Jamaica, New York, are being remediated using soil vapor extraction (SVE) and air sparging (AS). The areal extent of the contaminated soil is estimated to be 70 acres and the volume of contaminated groundwater is estimated to be 2.3 million gallons. The remediation uses approximately 13,000 feet of horizontal SVE (HSVE) wells and 7,000 feet of horizontal AS (HAS) wells. The design of the HSVE and HAS wells was based on a pilot study followed by a full-scale test. In addition to the horizontal wells, 28 vertical AS wells and 15 vertical SVE wells are used. Three areas are being remediated, thus, three separate treatment systems have been installed. The SVE and AS wells are operated continuously while groundwater will be intermittently extracted at each HAS well, treated by liquid phase activated carbon and discharged into stormwater collection sewerage. Vapors extracted by the SVE wells are treated by vapor phase activated carbon and discharged into ambient air. The duration of the remediation is anticipated to be between two and three years before soil and groundwater are remediated to New York State cleanup criteria for the site. Based on the monitoring data for the first two months of operation, approximately 14,600 lbs. of vapor phase VOCs have been extracted. Analyses show that the majority of the VOCs are branched alkanes, branched alkenes, cyclohexane and methylated cyclohexanes

  4. Alleviation of Heavy Metal Stress in Plants and Remediation of Soil by Rhizosphere Microorganisms

    OpenAIRE

    Mishra, Jitendra; Singh, Rachna; Arora, Naveen K.

    2017-01-01

    Increasing concentration of heavy metals (HM) due to various anthropogenic activities is a serious problem. Plants are very much affected by HM pollution particularly in contaminated soils. Survival of plants becomes tough and its overall health under HM stress is impaired. Remediation of HM in contaminated soil is done by physical and chemical processes which are costly, time-consuming, and non-sustainable. Metal–microbe interaction is an emerging but under-utilized technology that can be ex...

  5. Rhizobia and their bio-partners as novel drivers for functional remediation in contaminated soils

    Science.gov (United States)

    Teng, Ying; Wang, Xiaomi; Li, Lina; Li, Zhengao; Luo, Yongming

    2015-01-01

    Environmental pollutants have received considerable attention due to their serious effects on human health. There are physical, chemical, and biological means to remediate pollution; among them, bioremediation has become increasingly popular. The nitrogen-fixing rhizobia are widely distributed in the soil and root ecosystems and can increase legume growth and production by supplying nitrogen, resulting in the reduced need for fertilizer applications. Rhizobia also possess the biochemical and ecological capacity to degrade organic pollutants and are resistant to heavy metals, making them useful for rehabilitating contaminated soils. Moreover, rhizobia stimulate the survival and action of other biodegrading bacteria, thereby lowering the concentration of pollutants. The synergistic action of multiple rhizobial strains enhances both plant growth and the availability of pollutants ranging from heavy metals to persistent organic pollutants. Because phytoremediation has some restrictions, the beneficial interaction between plants and rhizobia provides a promising option for remediation. This review describes recent advances in the exploitation of rhizobia for the rehabilitation of contaminated soil and the biochemical and molecular mechanisms involved, thereby promoting further development of this novel bioremediation strategy into a widely accepted technique. PMID:25699064

  6. Rhizobia and their bio-partners as novel drivers for functional remediation in contaminated soils

    Directory of Open Access Journals (Sweden)

    Ying eTeng

    2015-02-01

    Full Text Available Environmental pollutants have received considerable attention due to their serious effects on human health. There are physical, chemical, and biological means to remediate pollution; among them, bioremediation has become increasingly popular. The nitrogen-fixing rhizobia are widely distributed in the soil and root ecosystems and can increase legume growth and production by supplying nitrogen, resulting in the reduced need for fertilizer applications. Rhizobia also possess the biochemical and ecological capacity to degrade organic pollutants and are resistant to heavy metals, making them useful for rehabilitating contaminated soils. Moreover, rhizobia stimulate the survival and action of other biodegrading bacteria, thereby lowering the concentration of pollutants. The synergistic action of multiple rhizobial strains enhances both plant growth and the availability of pollutants ranging from heavy metals to persistent organic pollutants. Because phytoremediation has some restrictions, the beneficial interaction between plants and rhizobia provides a promising option for remediation. This review describes recent advances in the exploitation of rhizobia for the rehabilitation of contaminated soil and the biochemical and molecular mechanisms involved, thereby promoting further development of this novel bioremediation strategy into a widely accepted technique.

  7. Papers of the remediation technologies symposium 2005. CD-ROM ed.

    International Nuclear Information System (INIS)

    2005-01-01

    This conference was attended by over 500 delegates and provided an opportunity for industry, practitioners, researchers and regulators to discuss technical issues in environmental remediation research and recent innovations in soil and groundwater remediation. Sessions included presentations on in-situ, groundwater and surface water remediation. Issues concerning phytoremediation, natural attenuation, extraction and commercial redevelopment were examined. The aim of the conference was also to provide a forum for innovators in remediation to present new work. Topics included hydrocarbon and salt contamination; engineered soil cover for management of salt impacted sites; remediation and revegetation of tar sands composite tailings containing naphthenic acids; sorption of oil sands naphthenic acid mixtures; denitrification as a natural attenuation mechanism; sampling methodologies; variability assessments; stabilization treatment technologies; remediation of coal wastes; bioreactor landfills; well blowouts in Alberta; soil remediation in coarse gravelly soils; diesel-contaminated aquifers; gasoline spill remediation; soil vapour extraction systems; technological solutions for erosion control and water clarification; and cost-effective in-situ remediation strategies. Fifty-two technical presentations were given, of which 27 have been catalogued separately for inclusion in this database

  8. Papers of the remediation technologies symposium 2005. CD-ROM ed.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This conference was attended by over 500 delegates and provided an opportunity for industry, practitioners, researchers and regulators to discuss technical issues in environmental remediation research and recent innovations in soil and groundwater remediation. Sessions included presentations on in-situ, groundwater and surface water remediation. Issues concerning phytoremediation, natural attenuation, extraction and commercial redevelopment were examined. The aim of the conference was also to provide a forum for innovators in remediation to present new work. Topics included hydrocarbon and salt contamination; engineered soil cover for management of salt impacted sites; remediation and revegetation of tar sands composite tailings containing naphthenic acids; sorption of oil sands naphthenic acid mixtures; denitrification as a natural attenuation mechanism; sampling methodologies; variability assessments; stabilization treatment technologies; remediation of coal wastes; bioreactor landfills; well blowouts in Alberta; soil remediation in coarse gravelly soils; diesel-contaminated aquifers; gasoline spill remediation; soil vapour extraction systems; technological solutions for erosion control and water clarification; and cost-effective in-situ remediation strategies. Fifty-two technical presentations were given, of which 27 have been catalogued separately for inclusion in this database. tabs., figs.

  9. The development and testing of technologies for the remediation of mercury-contaminated soils, Task 7.52. Topical report, December 1992--December 1993

    International Nuclear Information System (INIS)

    Stepan, D.J.; Fraley, R.H.; Charlton, D.S.

    1994-02-01

    The release of elemental mercury into the environment from manometers that are used in the measurement of natural gas flow through pipelines has created a potentially serious problem for the gas industry. Regulations, particularly the Land Disposal Restrictions (LDR), have had a major impact on gas companies dealing with mercury-contaminated soils. After the May 8, 1993, LDR deadline extension, gas companies were required to treat mercury-contaminated soils by designated methods to specified levels prior to disposal in landfills. In addition, gas companies must comply with various state regulations that are often more stringent than the LDR. The gas industry is concerned that the LDRs do not allow enough viable options for dealing with their mercury-related problems. The US Environmental Protection Agency has specified the Best Demonstrated Available Technology (BDAT) as thermal roasting or retorting. However, the Agency recognizes that treatment of certain wastes to the LDR standards may not always be achievable and that the BDAT used to set the standard may be inappropriate. Therefore, a Treatability Variance Process for remedial actions was established (40 Code of Federal Regulations 268.44) for the evaluation of alternative remedial technologies. This report presents evaluations of demonstrations for three different remedial technologies: a pilot-scale portable thermal treatment process, a pilot-scale physical separation process in conjunction with chemical leaching, and a bench-scale chemical leaching process

  10. The phyto-remediation of radioactively contaminated land - a feasible approach or just bananas?

    International Nuclear Information System (INIS)

    Nesbitt, Victoria A

    2013-01-01

    Soil is an essential component of all terrestrial ecosystems and is under increasing threat from human activity. Techniques available for removing radioactive contamination from soil and aquatic substrates are limited and often costly to implement; particularly over large areas. Frequently, bulk soil removal, with its attendant consequences, is a significant component of the majority of contamination incidents. Alternative techniques capable of removing contamination or exposure pathways without damaging or removing the soil are therefore of significant interest. An increasing number of old nuclear facilities are entering 'care and maintenance', with significant ground contamination issues. Phyto-remediation - the use of plants' natural metabolic processes to remediate contaminated sites is one possible solution. Its key mechanisms include phyto-extraction and phyto-stabilisation. These are analogues of existing remedial techniques. Further, phyto-remediation can improve soil quality and stability and restore functionality. Information on the application of phyto-remediation in the nuclear industry is widely distributed over an extended period of time and sources. It is therefore difficult to quickly and effectively identify which plants would be most suitable for phyto-remediation on a site by site basis. In response, a phyto-remediation tool has been developed to address this issue. Existing research and case studies were reviewed to understand the mechanisms of phyto-remediation, its effectiveness and the benefits and limitations of implementation. The potential for cost recovery from a phyto-remediation system is also briefly considered. An overview of this information is provided here. From this data, a set of matrices was developed to guide potential users through the plant selection process. The matrices take the user through a preliminary screening process to determine whether the contamination present at their site is amenable to phyto-remediation

  11. Electrokinetic Enhanced Permanganate Delivery for Low Permeability Soil Remediation

    Science.gov (United States)

    Chowdhury, A. I.; Gerhard, J.; Reynolds, D. A.; Sleep, B. E.; O'Carroll, D. M.

    2016-12-01

    Contaminant mass sequestered in low permeability zones (LPZ) in the subsurface has become a significant concern due to back diffusion of contaminants, leading to contaminant rebound following treatment of the high permeability strata. In-situ remediation technologies such as in-situ chemical oxidation (ISCO) are promising, however, successful delivery of oxidants into silts and clays remains a challenge. Electrokinetics (EK) has been proposed as a technique that can overcome this challenge by delivering oxidants into low permeability soils. This study demonstrates the ability of EK to facilitate permanganate delivery into silt for treatment of trichloroethene (TCE). A two-dimensional sandbox was packed with alternate vertical layers of coarse sand and silt contaminated with high concentrations of aqueous phase TCE. Nine experiments were conducted to compare EK-enhanced in-situ chemical oxidation (EK-ISCO) to ISCO alone or EK alone. Frequent groundwater sampling at multiple locations combined with image analysis provided detailed mapping of TCE, permanganate, and manganese dioxide mass distributions. EK-ISCO successfully delivered the permanganate throughout the silt cross-section while ISCO without EK resulted in permanganate delivery only to the edges of the silt layer. EK-ISCO resulted in a 4.4 order-of-magnitude (OoM) reduction in TCE concentrations in the coarse sand compared to a 3.5 OoM reduction for ISCO alone. This study suggests that electrokinetics coupled with ISCO can achieve enhanced remediation of lower permeability strata, where remediation technologies for successful contaminant mass removal would otherwise be limited.

  12. Remediation of cadmium by Indian mustard (Brassica juncea L.) from cadmium contaminated soil: a phytoextraction study

    OpenAIRE

    Rajeev Kumar Bhadkariya; VK Jain; GPS Chak; SK Gupta

    2014-01-01

    Cadmium is a toxic metal for living organisms and an environmental contaminant. Soils in many parts of the world are slightly too moderately contaminated by Cd due to long term use and disposal of Cd-contaminated wastes. Cost effective technologies are needed to remove cadmium from the contaminated sites. Soil phytoextraction is engineering based, low cost and socially accepted developing technology that uses plants to clean up contaminants in soils. This technology can be adopted as a remedi...

  13. Application of Microbial Products to Promote Electrodialytic Remediation of Heavy Metal Contaminated Soil

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland

    2006-01-01

    remediation (EDR) method for efficient treatment of Pb-contaminated soil by application of microbial products. Mobilization of Pb in soil by complexation with exopolymers and whole or disintegrated cells was investigated in column studies. Although exopolymers were previously shown to mobilize Pb in soil...... as potential methods for promotion of EDR of Pb contaminated soil. By these methods mobilization of Pb would occur due to complexation with much smaller substances than the previously examined and rejected exopolymers, why they were considered more efficient for mobilization of Pb in an electric current field...... also rejected, primarily due to the insufficient concentrations produced by microorganisms in general and the unrealistic high costs of industrially produced siderophores in relation to the low value of the product to be treated. Furthermore no detection of siderophore production was possible during...

  14. The potential of willow for remediation of heavy metal polluted calcareous urban soils

    International Nuclear Information System (INIS)

    Jensen, Julie K.; Holm, Peter E.; Nejrup, Jens; Larsen, Morten B.; Borggaard, Ole K.

    2009-01-01

    Growth performance and heavy metal uptake by willow (Salix viminalis) from strongly and moderately polluted calcareous soils were investigated in field and growth chamber trials to assess the suitability of willow for phytoremediation. Field uptakes were 2-10 times higher than growth chamber uptakes. Despite high concentrations of cadmium (≥80 mg/kg) and zinc (≥3000 mg/kg) in leaves of willow grown on strongly polluted soil with up to 18 mg Cd/kg, 1400 mg Cu/kg, 500 mg Pb/kg and 3300 mg Zn/kg, it is unsuited on strongly polluted soils because of poor growth. However, willow proved promising on moderately polluted soils (2.5 mg Cd/kg and 400 mg Zn/kg), where it extracted 0.13% of total Cd and 0.29% of the total Zn per year probably representing the most mobile fraction. Cu and Pb are strongly fixed in calcareous soils. - Willow is suited for remediation of moderately heavy metal polluted calcareous soils

  15. Proceedings of the remediation technologies symposium 2007

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This conference provided a forum to discuss the remediation of contaminated sites. It was attended by all industry sectors that have an interest in learning about technical issues in environmental remediation research and the latest innovations in soil and groundwater remediation and industrial pollutant treatments. Cost effective in-situ and ex-situ soil reclamation strategies were presented along with groundwater and surface water remediation strategies. The diversified sessions at this conference were entitled: regulatory update; Montreal Centre of Excellence in Brownfields Rehabilitation; soil and groundwater remediation through the Program of Energy Research and Development at Environment Canada; technology from the Netherlands; bioremediation; hydrocarbons; in-situ remediation; phytoremediation; salt management; unique locations; and, miscellaneous issues. Some areas and case studies covered in the presentations included: biological and non-biological treatments; thermal desorption; encapsulation; natural attenuation; multi-phase extraction; electrochemical remediation; and membrane technology. The conference featured 63 presentations, of which 23 have been catalogued separately for inclusion in this database. tabs., figs.

  16. Proceedings of the remediation technologies symposium 2007

    International Nuclear Information System (INIS)

    2007-01-01

    This conference provided a forum to discuss the remediation of contaminated sites. It was attended by all industry sectors that have an interest in learning about technical issues in environmental remediation research and the latest innovations in soil and groundwater remediation and industrial pollutant treatments. Cost effective in-situ and ex-situ soil reclamation strategies were presented along with groundwater and surface water remediation strategies. The diversified sessions at this conference were entitled: regulatory update; Montreal Centre of Excellence in Brownfields Rehabilitation; soil and groundwater remediation through the Program of Energy Research and Development at Environment Canada; technology from the Netherlands; bioremediation; hydrocarbons; in-situ remediation; phytoremediation; salt management; unique locations; and, miscellaneous issues. Some areas and case studies covered in the presentations included: biological and non-biological treatments; thermal desorption; encapsulation; natural attenuation; multi-phase extraction; electrochemical remediation; and membrane technology. The conference featured 63 presentations, of which 23 have been catalogued separately for inclusion in this database. tabs., figs

  17. Some Case Studies on Metal-Microbe Interactions to Remediate Heavy Metals- Contaminated Soils in Korea

    Science.gov (United States)

    Chon, Hyo-Taek

    2015-04-01

    Conventional physicochemical technologies to remediate heavy metals-contaminated soil have many problems such as low efficiency, high cost and occurrence of byproducts. Recently bioremediation technology is getting more and more attention. Bioremediation is defined as the use of biological methods to remediate and/or restore the contaminated land. The objectives of bioremediation are to degrade hazardous organic contaminants and to convert hazardous inorganic contaminants to less toxic compounds of safe levels. The use of bioremediation in the treatment of heavy metals in soils is a relatively new concept. Bioremediation using microbes has been developed to remove toxic heavy metals from contaminated soils in laboratory scale to the contaminated field sites. Recently the application of cost-effective and environment-friendly bioremediation technology to the heavy metals-contaminated sites has been gradually realized in Korea. The merits of bioremediation include low cost, natural process, minimal exposure to the contaminants, and minimum amount of equipment. The limitations of bioremediation are length of remediation, long monitoring time, and, sometimes, toxicity of byproducts for especially organic contaminants. From now on, it is necessary to prove applicability of the technologies to contaminated sites and to establish highly effective, low-cost and easy bioremediation technology. Four categories of metal-microbe interactions are generally biosorption, bioreduction, biomineralization and bioleaching. In this paper, some case studies of the above metal-microbe interactions in author's lab which were published recently in domestic and international journals will be introduced and summarized.

  18. GASReP/DESRT: Proceedings [of the] 2nd annual symposium on groundwater and soil remediation. Comptes rendus [de la] 2e symposium annuel sur la restauration des eaux souterraines et des sois contamines

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    A conference was held to discuss ground water and soil remediation with emphasis on the Canadian national Groundwater and Soil Remediation Program (GASReP) and the Development and Demonstration of Site Remediation Technology (DESRT) program. Papers were presented on the subjects of groundwater and soil remediation research projects, bioremediation, excavation and treatment, pumping and treatment/soil venting, and industry and government initiatives. Separate abstracts have been prepared for 15 papers from the conference.

  19. Evaluation of the potential of soil remediation by direct multi-channel pulsed corona discharge in soil.

    Science.gov (United States)

    Wang, Tie Cheng; Qu, Guangzhou; Li, Jie; Liang, Dongli

    2014-01-15

    A novel approach, named multi-channel pulsed corona discharge in soil, was developed for remediating organic pollutants contaminated soil, with p-nitrophenol (PNP) as the model pollutant. The feasibility of PNP degradation in soil was explored by evaluating effects of pulse discharge voltage, air flow rate and soil moisture on PNP degradation. Based on roles of chemically active species and evolution of degradation intermediates, PNP degradation processes were discussed. Experimental results showed that about 89.4% of PNP was smoothly degraded within 60min of discharge treatment at pulse discharge voltage 27kV, soil moisture 5% and air flow rate 0.8Lmin(-1), and the degradation process fitted the first-order kinetic model. Increasing pulse discharge voltage was found to be favorable for PNP degradation, but not for energy yield. There existed appropriate air flow rate and soil moisture for obtaining gratifying PNP degradation efficacy. Roles of radical scavenger and measurement of active species suggested that ozone, H2O2, and OH radicals played very important roles in PNP degradation. CN bond in PNP molecule was cleaved, and the main intermediate products such as hydroquinone, benzoquinone, catechol, phenol, acetic acid, formic acid, oxalic acid, NO2(-) and NO3(-) were identified. Possible pathway of PNP degradation in soil in such a system was proposed. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Novel Approach for the Remediation of Radioactive Cesium Contaminated Soil with nano-Fe/Ca/CaO Dispersion Mixture in Dry Condition

    Directory of Open Access Journals (Sweden)

    Mallampati S. R.

    2013-04-01

    Full Text Available Present study, first time we developed a nano-Fe/Ca/CaO dispersion mixture based remediation and volume reduction method of real radioactive cesium contaminated soils. After soil samples treated with 10wt% of nano-Fe/Ca/CaO dispersion mixtures, emitting radiation intensity was reduced from 4.00 μSv/h to 0.95 μSv/h in non-magnetic fraction soils. While, after treatment, about 30wt% magnetic and 70wt% nonmagnetic fraction soils were separated, and it’s condensed radioactive cesium concentration was about 80% and 20%, respectively. By this way, cesium contaminated soil volume can be reduced. These preliminary results appear to be very promising and the simple mixing with the addition of nano-Fe/Ca/CaO may be considered potentially applicable for the remediation and separation of radioactive Cs contaminated soil in dry conditions.

  1. Prediction of blood lead levels in children before and after remediation of soil samples in the upper Meza Valley, Slovenia.

    Science.gov (United States)

    Jez, Erika; Lestan, Domen

    2015-10-15

    The Meza Valley, Slovenia, has been contaminated by Pb smelting, resulting in an epidemic of lead poisoning in childhood. The potential of remediation with EDTA soil washing to mitigate the risk from Pb poisoning was investigated by applying the Integrated Exposure Uptake Bio-kinetic (IEUBK) model. Soils from 79 locations were collected and the total and bio-accessible Pb concentrations were determined before and after extraction with 60 mmol kg(-1) EDTA. Extraction reduced the soil Pb concentration in towns of Mezica, Zerjav and Crna by 53, 67 and 62%, respectively, and the concentration of in vitro bio-accessible Pb in the simulated human gastric phase by 2.6-, 3.2- and 2.9-times, respectively. The predictions of the IEUBK model based on Pb contamination data were verified with data on blood Pb levels in children. The IEUBK model predicted that, after soil remediation, the number of locations at which the expected blood Pb level in children was higher than the stipulated 10 μg d L(-1) would decrease by 90, 38 and 91% in the towns of Mezica, Zerjav and Crna, respectively. The results confirmed the feasibility of soil washing with EDTA as an efficient remediation measure in Mezica and Crna and advice for soil capping/removal for the most polluted town of Zerjav. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. the potential use of some amendments to remediate heavy metal polluted soil in egypt as determined by nuclear techniques

    International Nuclear Information System (INIS)

    Lotfy, S.M.

    2003-01-01

    the objectives of this work were four folds. first ,to characterize the behavior of some heavy metals (zinc and Cr) in tested-amended soil as affected by its physical and chemical properties using Zn 65 and Zr 51 tracer technique. second, to describe the sorption and desorption of these metals. (Zn 65 and Cr 51 ), which may help in remediation technique for the contaminated sites. third, to assess the effect of some oil amendments on heavy metals uptake and recovery from the contaminated soil . fourth, to enhance the remediation of pollutants as well as to protect soil quality. adsorption maximum for Zn 65 ranged between 161 and 909 mg Kg - 1 and from 303 mg Kg - 1 to 1111 mg Kg - 1 for Cr 51 . the highest values were reported for the organic enriched soils. the total contents of tested heavy metals increased in soil due to sludge and/or gypsum application . the addition of sludge resulted in a remarkable increase in heavy metals content

  3. Application of persulfate to remediate petroleum hydrocarbon-contaminated soil: feasibility and comparison with common oxidants.

    Science.gov (United States)

    Yen, Chia-Hsien; Chen, Ku-Fan; Kao, Chih-Ming; Liang, Shu-Hao; Chen, Ting-Yu

    2011-02-28

    In this study, batch experiments were conducted to evaluate the feasibility of petroleum-hydrocarbon contaminated soil remediation using persulfate oxidation. Various controlling factors including different persulfate and ferrous ion concentrations, different oxidants (persulfate, hydrogen peroxide, and permanganate), and different contaminants (diesel and fuel oil) were considered. Results show that persulfate oxidation is capable of treating diesel and fuel oil contaminated soil. Higher persulfate and ferrous ion concentrations resulted in higher diesel degrading rates within the applied persulfate/ferrous ion molar ratios. A two-stage diesel degradation was observed in the batch experiments. In addition, treatment of diesel-contaminated soil using in situ metal mineral activation under ambient temperature (e.g., 25°C) may be a feasible option for site remediation. Results also reveal that persulfate anions could persist in the system for more than five months. Thus, sequential injections of ferrous ion to generate sulfate free radicals might be a feasible way to enhance contaminant oxidation. Diesel oxidation efficiency and rates by the three oxidants followed the sequence of hydrogen peroxide>permanganate>persulfate in the limited timeframes. Results of this study indicate that the application of persulfate oxidation is a feasible method to treat soil contaminated by diesel and fuel oil. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. From conceptual model to remediation: bioavailability, a key to clean up heavy metal contaminated soils.

    Science.gov (United States)

    Petruzzelli, Gianniantonio; Pedron, Francesca; Pezzarossa, Beatrice

    2013-04-01

    Processes of metal bioavailability in the soil To know the bioavailability processes at site specific levels is essential to understand in detail the risks associated with pollution, and to support the decision-making process, i.e. description of the conceptual model and choice of clean up technologies. It is particularly important to assess how chemical, physical and biological processes in the soil affect the reactions leading to adsorption, precipitation or release of contaminants. The measurement of bioavailability One of the main difficulties in the practical application of the bioavailability concept in soil remediation is the lack of consensus on the method to be used to measure bioavailability. The best strategy is to apply a series of tests to assess bioavailability, since no applicable method is universally valid under all conditions. As an example, bioavailability tests for phytotechnology application should consider two distinct aspects: a physico-chemical driven solubilization process and a physiologically driven uptake process. Soil and plant characteristics strongly influence bioavailability. Bioavailability as a tool in remediation strategies Bioavailability can be used at all stages in remediation strategies: development of the conceptual model, evaluation of risk assessment, and selection of the best technology, considering different scenarios and including different environmental objectives. Two different strategies can be followed: the reduction and the increase of bioavailability. Procedures that reduce bioavailability aim to prevent the movement of pollutants from the soil to the living organisms, essentially by: i) removal of the labile phase of the contaminant, i.e. the fraction which is intrinsic to the processes of bioavailability (phytostabilization); ii) conversion of the labile fraction into a stable fraction (precipitation or adsorption); iii) increase of the resistance to mass transfer of the contaminants (inertization). Procedures

  5. Simultaneous removal of organic contaminants and heavy metals from kaolin using an upward electrokinetic soil remediation process

    International Nuclear Information System (INIS)

    Wang, J.-Y.; Huang, X.-J.; Kao, Jimmy C.M.; Stabnikova, Olena

    2007-01-01

    Kaolins contaminated with heavy metals, Cu and Pb, and organic compounds, p-xylene and phenanthrene, were treated with an upward electrokinetic soil remediation (UESR) process. The effects of current density, cathode chamber flushing fluid, treatment duration, reactor size, and the type of contaminants under the vertical non-uniform electric field of UESR on the simultaneous removal of the heavy metals and organic contaminants were studied. The removal efficiencies of p-xylene and phenanthrene were higher in the experiments with cells of smaller diameter or larger height, and with distilled water flow in the cathode chamber. The removal efficiency of Cu and Pb were higher in the experiments with smaller diameter or shorter height cells and 0.01 M HNO 3 solution as cathode chamber flow. In spite of different conditions for removal of heavy metals and organics, it is possible to use the upward electrokinetic soil remediation process for their simultaneous removal. Thus, in the experiments with duration of 6 days removal efficiencies of phenanthrene, p-xylene, Cu and Pb were 67%, 93%, 62% and 35%, respectively. The experiment demonstrated the feasibility of simultaneous removal of organic contaminants and heavy metals from kaolin using the upward electrokinetic soil remediation process

  6. [Recent advance in solidification/stabilization technology for the remediation of heavy metals-contaminated soil].

    Science.gov (United States)

    Hao, Han-zhou; Chen, Tong-bin; Jin, Meng-gui; Lei, Mei; Liu, Cheng-wu; Zu, Wen-pu; Huang, Li-mi

    2011-03-01

    Remediation of heavy metals-contaminated soil is still a difficulty and a hotspot of international research projects. At present, the technologies commonly adopted for the remediation of contaminated sites mainly include excavation, solidification/stabilization (S/S), soil washing, soil vapor extraction (SVE), thermal treatment, and bioremediation. Based on the S/S technical guidelines of Unite State Environmental Protection Agency (EPA) and United Kingdom Environment Agency (EA) and the domestic and foreign patents, this paper introduced the concepts of S/S and its development status at home and abroad, and discussed its future development directions. Solidification refers to a process that binds contaminated media with a reagent, changing the media's physical properties via increasing its compressive strength, decreasing its permeability, and encapsulating the contaminants to form a solid material. Stabilization refers to the process that involves a chemical reaction which reduces the leachability of a waste, chemically immobilizes the waste and reduces its solubility, making the waste become less harmful or less mobile. S/S technology includes cement solidification, lime pozzolanic solidification, plastic materials stabilization, vitrification, and regent-based stabilization. Stabilization (or immobilization) treatment processes convert contaminants to less mobile forms through chemical or thermal interactions. In stabilization technology, the aim of adding agents is to change the soil physical and chemical properties through pH control technology, redox potential technology, precipitation techniques, adsorption technology, and ion-exchange technology that change the existing forms of heavy metals in soil, and thus, reduce the heavy metals bioavailability and mobility. This review also discussed the S/S evaluation methods, highlighted the need to enhance S/S technology in the molecular bonding, soil polymers, and formulation of China's S/S technical guidelines.

  7. The Use of Plants for Remediation of Metal-Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Andon Vassilev

    2004-01-01

    Full Text Available The use of green plants to remove, contain, inactivate, or degrade harmful environmental contaminants (generally termed phytoremediation is an emerging technology. In this paper, an overview is given of existing information concerning the use of plants for the remediation of metal-contaminated soils. Both site decontamination (phytoextraction and stabilization techniques (phytostabilization are described. In addition to the plant itself, the use of soil amendments for mobilization (in case of phytoextraction and immobilization (in case of phytostabilization is discussed. Also, the economical impacts of changed land-use, eventual valorization of biomass, and cost-benefit aspects of phytoremediation are treated. In spite of the growing public and commercial interest and success, more fundamental research is needed still to better exploit the metabolic diversity of the plants themselves, but also to better understand the complex interactions between metals, soil, plant roots, and micro-organisms (bacteria and mycorrhiza in the rhizosphere. Further, more demonstration experiments are needed to measure the underlying economics, for publicacceptance and last but not least, to convince policy makers.

  8. The application of bioassays as indicators of petroleum-contaminated soil remediation.

    Science.gov (United States)

    Płaza, Grazyna; Nałecz-Jawecki, Grzegorz; Ulfig, Krzysztof; Brigmon, Robin L

    2005-04-01

    Bioremediation has proven successful in numerous applications to petroleum contaminated soils. However, questions remain as to the efficiency of bioremediation in lowering long-term soil toxicity. In the present study, the bioassays Spirotox, Microtox, Ostracodtoxkit F, umu-test with S-9 activation, and plant assays were applied, and compared to evaluate bioremediation processes in heavily petroleum contaminated soils. Six higher plant species (Secale cereale L., Lactuca sativa L., Zea mays L., Lepidium sativum L., Triticum vulgare L., Brassica oleracea L.) were used for bioassay tests based on seed germination and root elongation. The ecotoxicological analyses were made in DMSO/H2O and DCM/DMSO soil extracts. Soils were tested from two biopiles at the Czechowice oil refinery, Poland, that have been subjected to different bioremediation applications. In biopile 1 the active or engineered bioremediation process lasted four years, while biopile 2 was treated passively or non-engineered for eight months. The test species demonstrated varying sensitivity to soils from both biopiles. The effects on test organisms exposed to biopile 2 soils were several times higher compared to those in biopile 1 soils, which correlated with the soil contaminants concentration. Soil hydrocarbon concentrations indeed decreased an average of 81% in biopile 1, whereas in biopile 2 TPH/TPOC concentrations only decreased by 30% after eight months of bioremediation. The bioassays were presented to be sensitive indicators of soil quality and can be used to evaluate the quality of bioremediated soil. The study encourages the need to combine the bioassays with chemical monitoring for evaluation of the bioremediation effectiveness and assessing of the contaminated/remediated soils.

  9. DEMONSTRATION OF ELECTROCHEMICAL REMEDIATION TECHNOLOGIES-INDUCED COMPLEXATION

    Energy Technology Data Exchange (ETDEWEB)

    Barry L. Burks

    2002-12-01

    The Project Team is submitting this Topical Report on the results of its bench-scale demonstration of ElectroChemical Remediation Technologies (ECRTs) and in particular the Induced Complexation (ECRTs-IC) process for remediation of mercury contaminated soils at DOE Complex sites. ECRTs is an innovative, in-situ, geophysically based soil remediation technology with over 50 successful commercial site applications involving remediation of over two million metric tons of contaminated soils. ECRTs-IC has been successfully used to remediate 220 cu m of mercury-contaminated sediments in the Union Canal, Scotland. In that operation, ECRTs-IC reduced sediment total mercury levels from an average of 243 mg/kg to 6 mg/kg in 26 days of operation. The clean up objective was to achieve an average total mercury level in the sediment of 20 mg/kg.

  10. Independent Verification Survey of the Clean Coral Storage Pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project

    International Nuclear Information System (INIS)

    Wilson-Nichols, M.J.; Egidi, P.V.; Roemer, E.K.; Schlosser, R.M.

    2000-01-01

    f I The Oak Ridge National Laboratory (ORNL) Environmental Technology Section conducted an independent verification (IV) survey of the clean storage pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project (JAPCSRP) from January 18-25, 1999. The goal of the JAPCSRP is to restore a 24-acre area that was contaminated with plutonium oxide particles during nuclear testing in the 1960s. The selected remedy was a soil sorting operation that combined radiological measurements and mining processes to identify and sequester plutonium-contaminated soil. The soil sorter operated from about 1990 to 1998. The remaining clean soil is stored on-site for planned beneficial use on Johnston Island. The clean storage pile currently consists of approximately 120,000 m3 of coral. ORNL conducted the survey according to a Sampling and Analysis Plan, which proposed to provide an IV of the clean pile by collecting a minimum number (99) of samples. The goal was to ascertain wi th 95% confidence whether 97% of the processed soil is less than or equal to the accepted guideline (500-Bq/kg or 13.5-pCi/g) total transuranic (TRU) activity

  11. Remediation aspect of microbial changes of plant rhizosphere in mercury contaminated soil.

    Science.gov (United States)

    Sas-Nowosielska, Aleksandra; Galimska-Stypa, Regina; Kucharski, Rafał; Zielonka, Urszula; Małkowski, Eugeniusz; Gray, Laymon

    2008-02-01

    Phytoremediation, an approach that uses plants to remediate contaminated soil through degradation, stabilization or accumulation, may provide an efficient solution to some mercury contamination problems. This paper presents growth chamber experiments that tested the ability of plant species to stabilize mercury in soil. Several indigenous herbaceous species and Salix viminalis were grown in soil collected from a mercury-contaminated site in southern Poland. The uptake and distribution of mercury by these plants were investigated, and the growth and vitality of the plants through a part of one vegetative cycle were assessed. The highest concentrations of mercury were found at the roots, but translocation to the aerial part also occurred. Most of the plant species tested displayed good growth on mercury contaminated soil and sustained a rich microbial population in the rhizosphere. The microbial populations of root-free soil and rhizosphere soil from all species were also examined. An inverse correlation between the number of sulfur amino acid decomposing bacteria and root mercury content was observed. These results indicate the potential for using some species of plants to treat mercury contaminated soil through stabilization rather than extraction. The present investigation proposes a practical cost-effective temporary solution for phytostabilization of soil with moderate mercury contamination as well as the basis for plant selection.

  12. Biopiles - demonstration of cost effective biological remediation of furnace oil contaminated soils

    International Nuclear Information System (INIS)

    Kirchmair, G.A.

    1998-01-01

    Approximately 900 tonnes of soil was contaminated at a rural manufacturing facility near Collingwood, Ontario, when a 9000 litre underground furnace oil storage tank sprang a leak. The contaminated soil was excavated and stockpiled at the site and the leak was repaired. The Ontario Ministry of the Environment ordered that the owner treat the soil to the proper criteria or have the soil removed from the site and properly disposed of at a licensed landfill facility. Barenco was hired to treat the soil. Bioremediation began in December 1994 with the creation of nine above-ground biopiles which were constructed through the addition of nutrients (manure from a local farmer). Piping for air injection and treatment were located throughout the biopiles. The biopiles were then covered with 6 mil black HDPE plastic. The progress of the bioremediation was monitored regularly through measurement of carbon dioxide and oxygen concentrations in the biopiles. By October 1995, the soil was treated to within the appropriate criteria. In 10 months, the total petroleum hydrocarbon concentrations in the polluted soil were reduced from an average of 2690 ppm to 275 ppm. This simple and cost effective approach can also be used to remediate soils impacted with diesel fuels

  13. The improvement of Pilot-scale Electrokinetic for Radioactive Soil Decontamination

    International Nuclear Information System (INIS)

    Park, Hye Min; Kim, Gye Nam; Kim, Wan Suk; Moon, Jai Kwon

    2012-01-01

    Most nuclear facility sites have been contaminated by leakage of radioactive waste-solution due to corrosion of the waste-solution tanks and connection pipes by their long-term operation, set up around underground nuclear facilities. Therefore it was needed that the method to remediate a large volume of radioactive soil should be developed. Until now the soil washing method has studied to remediate soil contaminated with uranium, cobalt, cesium, and so on. But it has a lower removal efficiency of nuclide from soils and generated a large volume of waste-solution. And its application to the soil composed of fine particle is impossible. So, the electrokinetic method has been studied as a new technology for soil remediation recently. In this study, the original electrokinetic equipment of 50L suitable to soil contamination characteristics of Korean nuclear facility sites was manufactured for the remediation of soil contaminated with uranium. During experiment with the original electrokinetic equipment, many metal oxides were generated and were stuck on the cathod plate. Several methods to reduce the generation quantity of metal oxides in the electrokinetic equipment and to take off metal oxides from the cathod plate were improved. The soil with uranium was remediated with the improved electrokinetic equipment. The required time to remediate a radioactive soil to under a clearance concentration level was yielded through demonstration experiment with the improved electrokinetic equipment for its different radioactivity concentration

  14. The improvement of Pilot-scale Electrokinetic for Radioactive Soil Decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hye Min; Kim, Gye Nam; Kim, Wan Suk; Moon, Jai Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    Most nuclear facility sites have been contaminated by leakage of radioactive waste-solution due to corrosion of the waste-solution tanks and connection pipes by their long-term operation, set up around underground nuclear facilities. Therefore it was needed that the method to remediate a large volume of radioactive soil should be developed. Until now the soil washing method has studied to remediate soil contaminated with uranium, cobalt, cesium, and so on. But it has a lower removal efficiency of nuclide from soils and generated a large volume of waste-solution. And its application to the soil composed of fine particle is impossible. So, the electrokinetic method has been studied as a new technology for soil remediation recently. In this study, the original electrokinetic equipment of 50L suitable to soil contamination characteristics of Korean nuclear facility sites was manufactured for the remediation of soil contaminated with uranium. During experiment with the original electrokinetic equipment, many metal oxides were generated and were stuck on the cathod plate. Several methods to reduce the generation quantity of metal oxides in the electrokinetic equipment and to take off metal oxides from the cathod plate were improved. The soil with uranium was remediated with the improved electrokinetic equipment. The required time to remediate a radioactive soil to under a clearance concentration level was yielded through demonstration experiment with the improved electrokinetic equipment for its different radioactivity concentration

  15. Uptake of heavy metals by Brachiaria Decumbens and its mutant as a remediation agent for soil contaminated with oil sludge

    International Nuclear Information System (INIS)

    Ahmad Nazrul Abd Wahid; Latiffah Noordin; Abdul Razak Ruslan; Hazlina Abdullah; Khairuddin Abdul Rahim

    2006-01-01

    The Malaysian petroleum industry produces thousands of tonnes of oil sludge per year. Oil sludge is the residue accumulated during processing of petroleum at petroleum processing plants. Besides soil, mud and sand, oil sludge is often rich in radioactive substances, heavy metals and other toxic materials from hydrocarbon group which could contaminate and environment. In the present study the pasture grass Brachiaria decumbens and its mutant B. decumbens Kluang Comel were evaluated on their effectiveness as remediation agents for contaminated soils. The contaminating agent tested was the oil sludge with its hydrocarbons vaporised, obtained from the Waste Management Centre, MINT. Amongst the indicators for an effective remediation agent is the ability to accumulate heavy metals in their tissues without affecting their growth. This trial was conducted at MINT glasshouse, whereby the test plants were planted in pots in soil added with vaporised oil sludge. Analysis of heavy metals was through Inductive Coupled Plasma Mass Spectrometry (ICPMS) and Neutron Activation Analysis (NAA). This paper discusses the accumulation of heavy metals by B. decumbens and its mutant Kluang Comel and their growth performance, hence assessing their suitability as remediation agent in soil contaminated with oil sludge. (Author)

  16. Soil-Water Repellency and Critical Humidity as Cleanup Criteria for Remediation of a Hydrocarbon Contaminated Mud

    Science.gov (United States)

    Guzmán, Francisco Javier; Adams, Randy H.

    2010-05-01

    The majority of soil remediation programs focus mainly on reducing the hydrocarbon concentration, based on the assumption that the primary impact is toxicity and/or leachates and that these are directly proportional to concentration. None-the-less, interference with natural soil-water interactions are frequently more damaging, especially for sites contaminated with very viscous, weathered hydrocarbons. Therefore, the kind of hydrocarbons present in the soil and their interactions with soil surfaces may be more important than the overall hydrocarbon concentration in terms of soil restoration. One recently patented technology, the Chemical-Biological Stabilization process, focuses specifically on restoring soil fertility as the main objective for remediation of sites with agricultural use. This method was recently validated at an industrial scale by the treatment of 150 cubic meters of bentonitic drilling muds (70,5% fines) from an old sulphur mine, which were contaminated with very weathered oil (4° API), consisting of 31% asphaltenes. This material was treated by adding 4% (w/w, dry) of calcium hydroxide, followed by 4% (w/w, dry) of sugar cane cachasse (a fine fibered agricultural waste), thoroughly mixing between additions using an excavator. After the soil had dried sufficiently and the pH was soil water repellency. MED was measured on air dried soil and WDPT values were calculated from the extrapolation of penetration time vs. ethanol molarity functions (Rx=0,99). Additionally, water penetration times were measured at different humidities to determine critical moisture levels for absorption in soil humic substances while a vigorous vegetative growth was established. During two years of treatment the MED values were reduced 30% from 5,13 to 3,58M, and WDPT values were reduced over 25 times (from 10 exp5,6 s to 10 exp4,2 s). Critical humidity values varied from ~16,9 - 19,5%H for penetration in treated and untreated material. During the driest part of the year

  17. Harmful algal bloom removal and eutrophic water remediation by commercial nontoxic polyamine-co-polymeric ferric sulfate-modified soils.

    Science.gov (United States)

    Dai, Guofei; Zhong, Jiayou; Song, Lirong; Guo, Chunjing; Gan, Nanqin; Wu, Zhenbin

    2015-07-01

    Harmful algal bloom has posed great threat to drinking water safety worldwide. In this study, soils were combined with commercial nontoxic polyamine poly(epichlorohydrin-dimethylamine) (PN) and polymeric ferric sulfate (PFS) to obtain PN-PFS soils for Microcystis removal and eutrophic water remediation under static laboratory conditions. High pH and temperature in water could enhance the function of PN-PFS soil. Algal removal efficiency increased as soil particle size decreased or modified soil dose increased. Other pollutants or chemicals (such as C, P, and organic matter) in eutrophic water could participate and promote algal removal by PN-PFS soil; these pollutants were also flocculated. During PN-PFS soil application in blooming field samples, the removal efficiency of blooming Microcystis cells exceeded 99 %, the cyanotoxin microcystins reduced by 57 %. Water parameters (as TP, TN, SS, and SPC) decreased by about 90 %. CODMn, PO4-P, and NH4-N also sharply decreased by >45 %. DO and ORP in water improved. Netting and bridging effects through electrostatic attraction and complexation reaction could be the two key mechanisms of Microcystis flocculation and pollutant purification. Considering the low cost of PN-PFS soil and its nontoxic effect on the environment, we proposed that this soil combination could be applied to remove cyanobacterial bloom and remediate eutrophic water in fields.

  18. Assessment of trace element accumulation by earthworms in an orchard soil remediation study using soil amendments

    Science.gov (United States)

    Centofantia, Tiziana; Chaney, Rufus L.; Beyer, W. Nelson; McConnell, Laura L.; Davis, A. P.; Jackson, Dana

    2016-01-01

    This study assessed potential bioaccumulation of various trace elements in grasses and earthworms as a consequence of soil incorporation of organic amendments for in situ remediation of an orchard field soil contaminated with organochlorine and Pb pesticide residues. In this experiment, four organic amendments of differing total organic carbon content and quality (two types of composted manure, composted biosolids, and biochar) were added to a contaminated orchard field soil, planted with two types of grasses, and tested for their ability to reduce bioaccumulation of organochlorine pesticides and metals in earthworms. The experiment was carried out in 4-L soil microcosms in a controlled environment for 90 days. After 45 days of orchardgrass or perennial ryegrass growth, Lumbricus terrestris L. were introduced to the microcosms and exposed to the experimental soils for 45 days before the experiment was ended. Total trace element concentrations in the added organic amendments were below recommended safe levels and their phytoavailablity and earthworm availability remained low during a 90-day bioremediation study. At the end of the experiment, total tissue concentrations of Cu, Cd, Mn, Pb, and Zn in earthworms and grasses were below recommended safe levels. Total concentrations of Pb in test soil were similar to maximum background levels of Pb recorded in soils in the Eastern USA (100 mg kg−1 d.w.) because of previous application of orchard pesticides. Addition of aged dairy manure compost and presence of grasses was effective in reducing the accumulation of soil-derived Pb in earthworms, thus reducing the risk of soil Pb entry into wildlife food chains.

  19. Remediation of soils contaminated with polychlorinated biphenyls by microwave-irradiated manganese dioxide

    International Nuclear Information System (INIS)

    Huang Guanyi; Zhao Ling; Dong Yuanhua; Zhang Qin

    2011-01-01

    The removal of polychlorinated biphenyls (PCBs) using microwave-irradiated manganese dioxide (MnO 2 ) in PCB-contaminated soils under different conditions is investigated. The removal of PCB77 in two actual soil samples exhibits strong pH-dependent behavior, and the removal efficiency is higher in acidic soil (Ali-Perudic Ferrosols) than that in neutral soil (Udic Argosols). The removal kinetics of PCB77 using microwave-irradiated MnO 2 under different experimental conditions fits a pseudo-first-order kinetic model well. Both the removal efficiency and the kinetic constant (k) values of PCB77 in Ali-Perudic Ferrosols considerably increase, although in a nonlinear fashion, as the initial amount of MnO 2 is increased, as the treated soil mass is increased, and as the microwave power is increased. The reactivity of three PCBs (PCB28, PCB77, and PCB118) did not present as a function of the degree of chlorination in the reaction with microwave-irradiated MnO 2 . The pronounced removal of three PCBs in contaminated soil (all above 95%) indicates that MnO 2 in combination with microwave irradiation is promising for technological applications that seek to remediate sites critically polluted with PCBs.

  20. Remediation of Cu in the Contaminated Soil by Using Equisetum debile (Horsetail

    Directory of Open Access Journals (Sweden)

    Irna Rahmaniar

    2015-05-01

    Full Text Available Paddy fields in the Rancaekek area, Bandung Regency-Indonesia, has been contaminated by textile wastewater. The area needs to recover back to its normal condition and function. Several compounds were found in the soil, such as Cu, Zn, Pb, Cd, Co, Ni, and Cr. Phytoremediation was selected as a site remediation strategy, which employs plants to remove non-volatile and immiscible soil contents. The objective of the study was to determine the ability of Equisetum debile to absorb Cu from the contaminated soil. Cu measurement was conducted by using the AAS (Atomic Absorption Spectrophotometer method. The study has shown that Equisetum debile can absorb Cu concentrations of up to 25.3 ppm in 60 days after initial planting. However, the Enrichment Coefficient value (0.392 indicated that Equisetum debile was not efficient as a hyperaccumulator plant.

  1. Upscaling Self-Sustaining Treatment for Active Remediation (STAR): Experimental Study of Scaling Relationships for Smouldering Combustion to Remediate Soil

    Science.gov (United States)

    Kinsman, L.; Gerhard, J.; Torero, J.; Scholes, G.; Murray, C.

    2013-12-01

    Self-sustaining Treatment for Active Remediation (STAR) is a relatively new remediation approach for soil contaminated with organic industrial liquids. This technology uses smouldering combustion, a controlled, self-sustaining burning reaction, to destroy nonaqueous phase liquids (NAPLs) and thereby render soil clean. While STAR has been proven at the bench scale, success at industrial scales requires the process to be scaled-up significantly. The objective of this study was to conduct an experimental investigation into how liquid smouldering combustion phenomena scale. A suite of detailed forward smouldering experiments were conducted in short (16 cm dia. x 22 cm high), intermediate (16 cm dia. x 127 cm high), and large (97 cm dia. x 300 cm high; a prototype ex-situ reactor) columns; this represents scaling of up to 530 times based on the volume treated. A range of fuels were investigated, with the majority of experiments conducted using crude oil sludge as well as canola oil as a non-toxic surrogate for hazardous contaminants. To provide directly comparable data sets and to isolate changes in the smouldering reaction which occurred solely due to scaling effects, sand grain size, contaminant type, contaminant concentration and air injection rates were controlled between the experimental scales. Several processes could not be controlled and were identified to be susceptible to changes in scale, including: mobility of the contaminant, heat losses, and buoyant flow effects. For each experiment, the propagation of the smouldering front was recorded using thermocouples and analyzed by way of temperature-time and temperature-distance plots. In combination with the measurement of continuous mass loss and gaseous emissions, these results were used to evaluate the fundamental differences in the way the reaction front propagates through the mixture of sand and fuel across the various scales. Key governing parameters were compared between the small, intermediate, and large

  2. Studies on soil contamination due to used motor oil and its remediation

    International Nuclear Information System (INIS)

    Singh, S.K.; John, S.; Srivastava, R.K.

    2009-01-01

    Used motor oil (UMO) contains lead, chromium, cadmium, naphthalene, chlorinated hydrocarbons and sulphur. Although UMO can be recycled if safely and properly collected, in many cases it is poured into open drains or thrown into the trash where it can contaminate the subsurface soil and ground water. A study was conducted to evaluate the changes in behaviour of soils due to interaction with UMO followed by its remediation. Different types of soils classified as clay with low plasticity, clay with high plasticity, and poorly graded sand were used for the study. Used motor oil was the contaminant and sodium dedecyl sulphate (SDS) was used as the surfactant for decontamination. In order to compare the geotechnical properties before and after contamination, laboratory studies were conducted on uncontaminated soil samples as well as on soil samples simulated to varying degrees of contamination. The contaminants in the soil matrix were held either by chemical adsorption or entrained within the pore space surrounding the soil grains. The study showed that the sensitivity of soil to the contaminants depends not only on the local environment, but also on the mineral structure, particle size, bonding and ion exchange capacity. It was observed that the original geotechnical properties of soils could be almost restored upon decontamination with SDS washing at an optimum dosage. 31 refs., 7 tabs., 3 figs

  3. The large-scale process of microbial carbonate precipitation for nickel remediation from an industrial soil.

    Science.gov (United States)

    Zhu, Xuejiao; Li, Weila; Zhan, Lu; Huang, Minsheng; Zhang, Qiuzhuo; Achal, Varenyam

    2016-12-01

    Microbial carbonate precipitation is known as an efficient process for the remediation of heavy metals from contaminated soils. In the present study, a urease positive bacterial isolate, identified as Bacillus cereus NS4 through 16S rDNA sequencing, was utilized on a large scale to remove nickel from industrial soil contaminated by the battery industry. The soil was highly contaminated with an initial total nickel concentration of approximately 900 mg kg -1 . The soluble-exchangeable fraction was reduced to 38 mg kg -1 after treatment. The primary objective of metal stabilization was achieved by reducing the bioavailability through immobilizing the nickel in the urease-driven carbonate precipitation. The nickel removal in the soils contributed to the transformation of nickel from mobile species into stable biominerals identified as calcite, vaterite, aragonite and nickelous carbonate when analyzed under XRD. It was proven that during precipitation of calcite, Ni 2+ with an ion radius close to Ca 2+ was incorporated into the CaCO 3 crystal. The biominerals were also characterized by using SEM-EDS to observe the crystal shape and Raman-FTIR spectroscopy to predict responsible bonding during bioremediation with respect to Ni immobilization. The electronic structure and chemical-state information of the detected elements during MICP bioremediation process was studied by XPS. This is the first study in which microbial carbonate precipitation was used for the large-scale remediation of metal-contaminated industrial soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Removal and Remediation Effects of Cd from Cadmium-contaminated Farmland Soils by A Magnetic Solid Chelator

    Directory of Open Access Journals (Sweden)

    NIE Xin-xing

    2017-10-01

    Full Text Available In this paper, a simulated experiment was carried out to study the removal and remediation effects of Cd from cadmium-contaminated farmland soils by a magnetic solid chelator(MSC at different application rates as well as its recovery rates and chelating capacity for Cd. The results showed that when the application rates of MSC materials was between 0.4% and 1.2%, the removal rate of total Cd and available Cd were 15.91%~17.69% and 33.33%~50.26%, respectively. And the MSC recovery rates were between 74.01% and 94.33% which increased with the increase of application rates of MSC and gradually tended to be stable. The content of Cd in recycled magnetic materials(mainly MSC was between 19.31 mg·kg-1 to 25.72 mg·kg-1, reaching to the highest at the application rates of 0.4% which was significantly higher than those of 0.8%, 1% and 1.2% treatment. But the content of Cd in magnetic materials had the trend that decreased with the increase of the recovery amount of MSC. The amount of Cd chelated by magnetic materials was nearly equal to the removal amount of Cd from soil at the 0.8% and 1.2% treatments. Besides, the Cd concentration in water samples was lower thanⅠ-level standard issued by the surface water environment quality standard(GB 3838-2002, meaning that it would not be a new pollution source. Therefore, MSC does have some removal and remediation effects on soil Cd and will provide a new method for remediation of heavy metals in farmland soils.

  5. Sorption interactions of heavy metals with biochar in soil remediation studies

    Science.gov (United States)

    Fristak, Vladimir; Friesl-Hanl, Wolfgang; Wawra, Anna; Soja, Gerhard

    2015-04-01

    The search for new materials in soil remediation applications has led to new conversion technologies such as carbonization and pyrolysis. Biochar represents the pyrolytic product of different biomass input materials processed at 350-1000°C and anoxic conditions. The pyrolysis temperature and feedstock have a considerable influence on the quality of the charred product and also its main physico-chemical properties. Biochar as porous material with large specific surface and C-stability is utilized in various environmental and agricultural technologies. Carbon sequestration, increase of soil water-holding capacity and pH as well as sorption of different xenobiotics present only a fraction of the multitude of biochar application possibilities. Heavy metals as potential sources of ecotoxicological risks are characterized by their non-degradability and the potential transfer into the food chain. Carbonaceous materials have been used for a long time as sorbents for heavy metals and organic contaminants in soil and water technologies. The similarity of biochar with activated carbon predetermines this material as remediation tool which plays an important role in heavy metal immobilization and retention with a parallel reduction in the risk of ground water and food crop contamination. In all this processes the element-specific sorption behaviour of biochar creates new conditions for pollutant binding. Sorption interaction and separation of contaminants from soil solution or waste effluent can be affected by wide-ranging parameters. In detail, our study was based on batch-sorption comparisons of two biochars produced from wood chips and green waste residues. We observed that sorption efficiency of biochar for model bivalent heavy metals (Cd, Zn, Cu) can be influenced by equilibrium parameters such as pH, contact time, initial concentration of metal in reaction solutions, presence of surfactants and chemical modification by acid hydrolysis, esterification and methylation. The

  6. Use of a risk-based hydrogeologic model to set remedial goals in a Puget Sound basin watershed

    International Nuclear Information System (INIS)

    Pascoe, G.; Gould, L.; Martin, J.; Riley, M.; Floyd, T.

    1995-01-01

    The Port of Seattle is redeveloping industrial land for a container terminal along the southwest Seattle waterfront. Concrete, asphalt, ballast, and a landfill geomembrane will cover the site and prevent direct contact with surface soils, so remedial goals focused on groundwater contamination from subsurface soils. Groundwater at the site flows along an old stormwater drain, in a filled estuary of a small creek, to Elliott Bay. Remedial goals for a variety of organic chemicals, metals, and TPH in subsurface soils were identified to protect marine receptors in the bay and their consumers. Washington State and federal marine water quality criteria were the starting points in the risk-based model, and corresponding concentrations of chemicals in groundwater were back-calculated through a hydrogeologic model. The hydrogeologic model included a mixing zone component in the bay and dilution/attenuation factors along the groundwater transport pathway that were determined from onsite groundwater and surface water chemical concentrations. A rearranged Summers equation was then applied in a second back-calculation to determine subsurface soil concentrations corresponding to the back calculated groundwater concentrations. The equation was based on calculated aquifer flow rates for the small creek watershed and rates of infiltration through surface materials calculated for each redevelopment soil cover type by the HELP model. Results of the risk-based hydrogeologic back-calculation model indicate that, depending on soil cover type at the site, concentrations in subsurface soils of PCBs from 2 to 1,000 mg/kg and of TPH up to free phase concentration would not result in risks to marine organisms or their consumers in Elliott Bay

  7. A greenhouse study on arsenic remediation potential of Vetiver grass (Vetiveria Zizanioides) as a function of soil physico-chemical properties

    Science.gov (United States)

    Quispe, M. A.; Datta, R.; Sarkar, D.; Sharma, S.

    2006-05-01

    Arsenic is one of the most harmful and toxic metals, being a Group A human carcinogen. Mining activities as well as the use of arsenic-containing pesticides have resulted in the contamination of a wide variety of sites including mine tailings, cattle dip sites, wood treatment sites, pesticide treatment areas, golf courses, etc. Phytoremediation has emerged as a novel and promising technology, which uses plants to clean up contaminated soil and water taking advantage of plant's natural abilities to extract and accumulate various contaminants. This method has distinct advantages, since it maintains the biological properties and physical structure of the soil, is environment friendly, and above all, inexpensive. However, effective remediation of contaminated residential soils using a specific plant species is an immensely complex task whose success depends on a multitude of factors including the ability of the target plant to uptake, translocate, detoxify, and accumulate arsenic in its system. One of the major challenges in phytoremediation lies in identifying a fast- growing, high biomass plant that can accumulate the contaminant in its harvestable parts. vetiver grass (Vetiveria zizanioides) is a fast-growing perennial grass with strong ecological adaptability and large biomass. While this plant is not a hyperaccumulator of arsenic, it has been reported to be able to tolerate and accumulate considerable amounts of arsenic. Being a high biomass, fast-growing plant, vetiver has the potential to be used for arsenic remediation. The present study investigates the potential of vetiver grass to tolerate and accumulate arsenic in soils with varying physico-chemical properties. A greenhouse study is in progress to study the uptake, tolerance and stress response of vetiver grass to inorganic arsenical pesticide. A column study was set up using 5 soils (Eufaula, Millhopper, Orelia, Orla, and Pahokee Muck) contaminated with sodium arsenite at 4 different concentrations of

  8. Ecopiling: a combined phytoremediation and passive biopiling system for remediating hydrocarbon impacted soils at field scale

    OpenAIRE

    Germaine, Kieran J.; Byrne, John; Liu, Xuemei; Keohane, Jer; Culhane, John; Lally, Richard D.; Kiwanuka, Samuel; Ryan, David; Dowling, David N.

    2015-01-01

    Biopiling is an ex situ bioremediation technology that has been extensively used for remediating a wide range of petrochemical contaminants in soils. Biopiling involves the assembling of contaminated soils into piles and stimulating the biodegrading activity of microbial populations by creating near optimum growth conditions. Phytoremediation is another very successful bioremediation technique and involves the use of plants and their associated microbiomes to degrade, sequester or bio-accumu...

  9. Environmental impact of hazardous inorganic materials. Pollution and remediation of soils

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, S.; Hakuta, T. [National Institute of Materials and Chemical Research, Tsukuba (Japan); Barrington, S.; Wasay, S. [McGill University, (Canada)

    1998-02-10

    Recently, soil pollution has become a grave social problem. This paper reviews history, laws and regulations, current status and measures related to soil pollution, centered by those of Japan. Soil pollution problems in Japan date back to around 1880, when pollution of the Watarase River basin started by waste water exhausted from Asio Mine. Various grave problems have been recorded since then, including the Itai-itai and Minamata Diseases caused by Cd and methyl mercury, respectively, which started in 1945 and 1956, with the result that the government has amended laws/regulations related to treatment and cleaning of industrial wastes. Later, the related laws/regulations have been frequently amended, and the environmental standards related to soil pollution was established in 1991. Treatment for remediation of polluted soils has been effected with the aid of inorganic acids, organic solvents, chelating agents, natural organic acids (such as acetic and formic acids) and biological surface active agents. They must be carefully planned to take into consideration various aspects, such as pH level and other conditions, cost and environmental safety, before being actually used. One of the recommended measures is on-the-site treatment in an enclosed space while regenerating and recycling the agent. 66 refs., 7 figs., 8 tabs.

  10. Use of clay to remediate cadmium contaminated soil under different water management regimes.

    Science.gov (United States)

    Li, Jianrui; Xu, Yingming

    2017-07-01

    We examined in situ remediation of sepiolite on cadmium-polluted soils with diverse water regimes, and several variables including brown rice Cd, exchangeable Cd, pH, and available Fe/P. pH, available Fe/P in soils increased gradually during continuous flooding, which contributed to Cd absorption on colloids. In control group (untreated soils), compared to conventional irrigation, brown rice Cd in continuous flooding reduced by 37.9%, and that in wetting irrigation increased by 31.0% (psoils reduced by 44.4%, 34.5% and 36.8% under continuous flooding, conventional irrigation and wetting irrigation (psoils reduced by 27.5-49.0%, 14.3-40.5%, and 24.9-32.8% under three water management regimes (psoils were higher in continuous flooding than in conventional irrigation and wetting irrigation. Continuous flooding management promoted soil Cd immobilization by sepiolite. Copyright © 2017. Published by Elsevier Inc.

  11. Feasibility study of the use of different extractant agents in the remediation of a mercury contaminated soil from Almaden

    DEFF Research Database (Denmark)

    Subirés-Muñoz, J.D.; García-Rubio, A.; Vereda-Alonso, C.

    2011-01-01

    The soil of Almaden mining district in Spain has a high concentration of mercury (1000mgkg−1), therefore decontamination activities are necessary. This paper studies the effectiveness of some chelant agents (thiosulfate, EDTA, iodide and HNO3) for the remediation of this soil which has been...

  12. Remediation of electronic waste polluted soil using a combination of persulfate oxidation and chemical washing.

    Science.gov (United States)

    Chen, Fu; Luo, Zhanbin; Liu, Gangjun; Yang, Yongjun; Zhang, Shaoliang; Ma, Jing

    2017-12-15

    Laboratory experiments were conducted to investigate the efficiency of a simultaneous chemical extraction and oxidation for removing persistent organic pollutants (POPs) and toxic metals from an actual soil polluted by the recycling activity of electronic waste. Various chemicals, including hydroxypropyl-β-cyclodextrin (HPCD), citric acid (CA) and sodium persulfate (SP) were applied synchronously with Fe 2+ activated oxidation to enhance the co-removal of both types of pollutants. It is found that the addition of HPCD can enhance POPs removal through solubilization of POPs and iron chelation; while the CA-chelated Fe 2+ activation process is effective for extracting metals and degrading residual POPs. Under the optimized reagent conditions, 69.4% Cu, 78.1% Pb, 74.6% Ni, 97.1% polychlorinated biphenyls, 93.8% polycyclic aromatic hydrocarbons, and 96.4% polybrominated diphenylethers were removed after the sequential application of SP-HPCD-Fe 2+ and SP-CA-Fe 2+ processes with a duration of 180 and 240 min, respectively. A high dehalogenation efficiency (84.8% bromine and 86.2% chlorine) is observed, suggesting the low accumulation of halogen-containing organic intermediates. The remediated soil can satisfy the national soil quality standard of China. Collectively, co-contaminated soil can be remediated with reasonable time and capital costs through simultaneous application of persulfate oxidation and chemical extraction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Hybrid life cycle assessment comparison of colloidal silica and cement grouted soil barrier remediation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, Patricia M., E-mail: pmg24@drexel.edu [Civil, Architectural and Environmental Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19038 (United States); Spatari, Sabrina; Cucura, Jeffrey [Civil, Architectural and Environmental Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19038 (United States)

    2013-04-15

    Highlights: ► We use LCA to study environmental impacts of grouting techniques for site remediation. ► We consider colloidal silica permeation grouting and cement jet grouting. ► Manufacturing and transportation contribute significantly in all impact categories. ► Activity outside of direct site activity is important in assessing impacts. ► LCA can be used to consider sustainability criteria for remediation decisions. -- Abstract: Site remediation involves balancing numerous costs and benefits but often neglects the environmental impacts over the entire project life cycle. Life cycle assessment (LCA) offers a framework for inclusion of global environmental “systems-level” decision metrics in combination with technological and cost analysis. We compare colloidal silica (CS) and cement grouted soil barrier remediation technologies for soils affected by low level radionuclides at a U.S. Superfund site using hybrid LCA methods. CS is a new, high performance grouting material installed using permeation grouting techniques. Cement, a more traditional grouting material, is typically installed using jet grouting techniques. Life cycle impacts were evaluated using the US EPA TRACI 2 model. Results show the highest life cycle environmental impacts for the CS barrier occur during materials production and transportation to the site. In general, the life cycle impacts for the cement barrier were dominated by materials production; however, in the extreme scenario the life cycle impacts were dominated by truck transportation of spoils to a distant, off-site radioactive waste facility. It is only in the extreme scenario tested in which soils are transported by truck (Option 2) that spoils waste transport dominates LCIA results. Life cycle environmental impacts for both grout barriers were most sensitive to resource input requirements for manufacturing volumes and transportation. Uncertainty associated with the efficacy of new technology such as CS over its required

  14. Hybrid life cycle assessment comparison of colloidal silica and cement grouted soil barrier remediation technologies

    International Nuclear Information System (INIS)

    Gallagher, Patricia M.; Spatari, Sabrina; Cucura, Jeffrey

    2013-01-01

    Highlights: ► We use LCA to study environmental impacts of grouting techniques for site remediation. ► We consider colloidal silica permeation grouting and cement jet grouting. ► Manufacturing and transportation contribute significantly in all impact categories. ► Activity outside of direct site activity is important in assessing impacts. ► LCA can be used to consider sustainability criteria for remediation decisions. -- Abstract: Site remediation involves balancing numerous costs and benefits but often neglects the environmental impacts over the entire project life cycle. Life cycle assessment (LCA) offers a framework for inclusion of global environmental “systems-level” decision metrics in combination with technological and cost analysis. We compare colloidal silica (CS) and cement grouted soil barrier remediation technologies for soils affected by low level radionuclides at a U.S. Superfund site using hybrid LCA methods. CS is a new, high performance grouting material installed using permeation grouting techniques. Cement, a more traditional grouting material, is typically installed using jet grouting techniques. Life cycle impacts were evaluated using the US EPA TRACI 2 model. Results show the highest life cycle environmental impacts for the CS barrier occur during materials production and transportation to the site. In general, the life cycle impacts for the cement barrier were dominated by materials production; however, in the extreme scenario the life cycle impacts were dominated by truck transportation of spoils to a distant, off-site radioactive waste facility. It is only in the extreme scenario tested in which soils are transported by truck (Option 2) that spoils waste transport dominates LCIA results. Life cycle environmental impacts for both grout barriers were most sensitive to resource input requirements for manufacturing volumes and transportation. Uncertainty associated with the efficacy of new technology such as CS over its required

  15. An Integrated H-G Scheme Identifying Areas for Soil Remediation and Primary Heavy Metal Contributors: A Risk Perspective.

    Science.gov (United States)

    Zou, Bin; Jiang, Xiaolu; Duan, Xiaoli; Zhao, Xiuge; Zhang, Jing; Tang, Jingwen; Sun, Guoqing

    2017-03-23

    Traditional sampling for soil pollution evaluation is cost intensive and has limited representativeness. Therefore, developing methods that can accurately and rapidly identify at-risk areas and the contributing pollutants is imperative for soil remediation. In this study, we propose an innovative integrated H-G scheme combining human health risk assessment and geographical detector methods that was based on geographical information system technology and validated its feasibility in a renewable resource industrial park in mainland China. With a discrete site investigation of cadmium (Cd), arsenic (As), copper (Cu), mercury (Hg) and zinc (Zn) concentrations, the continuous surfaces of carcinogenic risk and non-carcinogenic risk caused by these heavy metals were estimated and mapped. Source apportionment analysis using geographical detector methods further revealed that these risks were primarily attributed to As, according to the power of the determinant and its associated synergic actions with other heavy metals. Concentrations of critical As and Cd, and the associated exposed CRs are closed to the safe thresholds after remediating the risk areas identified by the integrated H-G scheme. Therefore, the integrated H-G scheme provides an effective approach to support decision-making for regional contaminated soil remediation at fine spatial resolution with limited sampling data over a large geographical extent.

  16. Development of in situ vitrification for remediation of ORNL contaminated soils

    International Nuclear Information System (INIS)

    Tixier, J.S.; Spalding, B.P.

    1994-08-01

    A full-scale field treatability study of in situ vitrification (ISV) is underway at the Oak Ridge National Laboratory (ORNL) for the remediation of radioactive liquid waste seepage pits and trenches that received over one million curies of mixed fission products (mostly 137 Cs and 90 Sr) during the 1950s and 1960s. The treatability study is being conducted on a portion of the original seepage pit and will support an Interim Record of Decision (IROD) for closure of one or more of the seven seepage pits and trenches in early fiscal year (FY) 1996. Mr treatability study will establish ft technical performance of ISV for remediation of the contaminated soil sites. Melt operations at ORNL are expected to begin in early FY 1994. This paper presents the latest accomplishments of the project in preparation for the field testing. Discussion centers on the results of a parametric crucible melt study, a description of the site characterization efforts, and the salient features of a new hood design

  17. Fenton oxidation to remediate PAHs in contaminated soils: A critical review of major limitations and counter-strategies.

    Science.gov (United States)

    Usman, M; Hanna, K; Haderlein, S

    2016-11-01

    Fenton oxidation constitutes a viable remediation strategy to remove polycyclic aromatic hydrocarbons (PAHs) in contaminated soils. This review is intended to illustrate major limitations associated with this process like acidification, PAH unavailability, and deterioration of soil quality along with associated factors, followed by a critical description of various developments to overcome these constraints. Considering the limitation that its optimal pH is around 3, traditional Fenton treatment could be costly, impractical in soil due to the high buffering capacity of soils and associated hazardous effects. Use of various chelating agents (organic or inorganic) allowed oxidation at circumneutral pH but factors like higher oxidant demand, cost and toxicity should be considered. Another alternative is the use of iron minerals that can catalyze Fenton-like oxidation over a wide range of pH, but mobility of these particles in soils (i.e. saturated and unsaturated zones) should be investigated prior to in-situ applications. The PAH-unavailability is the crucial limitation hindering their effective degradation. Research data is compiled describing various strategies to address this issue like the use of availability enhancement agents, extraction or thermal pretreatment. Last section of this review is devoted to describe the effects of various developments in Fenton treatment onto soil quality and native microbiota. Finally, research gaps are discussed to suggest future directions in context of applying Fenton oxidation to remediate contaminated soils. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Investigation on reusing water treatment residuals to remedy soil contaminated with multiple metals in Baiyin, China

    International Nuclear Information System (INIS)

    Wang, Changhui; Zhao, Yuanyuan; Pei, Yuansheng

    2012-01-01

    Highlights: ► Fe/Al water treatment residuals (FARs) can stabilize As, Pb, Ni, Zn, Cr and Cu. ► FARs cannot stabilize Ba and Cd. ► The properties of FARs and soil affect the FARs’ ability of stabilizing metals. - Abstract: In this work, the remediation of soils contaminated with multiple metals using ferric and alum water treatment residuals (FARs) in Baiyin, China, was investigated. The results of metals fractionation indicated that after the soil was treated with FARs, arsenic (As), lead (Pb), nickel (Ni), zinc (Zn) and copper (Cu) could be transformed into more stable forms, i.e., As bound in crystalline Fe/Al oxides and other metals in the oxidable and residual forms. However, the forms of chromium (Cr) and cadmium (Cd) were unaffected. Interestingly, due to the effect of FARs, barium (Ba) was predominantly transformed into more mobile forms. The bioaccessibility extraction test demonstrated that the FARs reduced the bioaccessibility of As by 25%, followed by Cu, Cr, Zn, Ni and Pb. The bioaccessibility of Cd and Ba were increased; in particular, there was an increase of 41% for Ba at the end of the test. In conclusion, the FARs can be used to remedy soil contaminated with multiple metals, but comprehensive studies are needed before practical applications of this work.

  19. Remedial action of radium contaminated residential properties

    International Nuclear Information System (INIS)

    White, D.; Eng, J.

    1986-01-01

    Since November 1983, the New Jersey Department of Environmental Protection (NJDEP) and the US Environmental Protection Agency (USEPA) have been in the process of identifying properties in Montclair, Glen Ridge and West Orange, New Jersey, which were built over radium contaminated soil landfilled areas. Elevated indoor radon concentrations prompted the Centers for Disease Control (CDC) to issue a health advisory which included permanent remediation of radon progeny levels in excess of 0.02 Working Levels within two years of discovery. In order to expedite remedial action, NJDEP undertook a ten million dollar cleanup program. Remedial Action at the 12 residential properties encountered some unanticipated problems despite the efforts of numerous government agencies and their contractors to characterize the contamination as much as possible prior to remediation. Some of the unanticipated issues include contamination from other radionuclides, underestimation of removal volumes, and controversy over the transportation and disposal of the radium contaminated soil at a commercial facility in Nevada. This paper will review the approach taken by NJDEP to the remedial action for radium contaminated soil, discuss some of the issues encountered during the remedial action, and provide post remedial action data

  20. Developing a disposal and remediation plan

    International Nuclear Information System (INIS)

    Messier, T.S.

    1999-01-01

    The environmental release of wastes generated by the upstream oil and gas industry in Alberta can result in polluted soil and groundwater at several facilities across the province. Responsibility for decommissioning upstream oil and gas facilities falls under the jurisdiction of the Alberta Energy and Utilities Board (EUB) and Alberta Environmental Protection (AEP). This paper outlines a protocol that can serve as a framework for the development of a plan to dispose of oilfield waste and to remediate related contaminated soils. The components involved in developing a disposal and remediation plan for oilfield wastes are: (1) identifying the potential source of pollution and oilfield waste generation, (2) characterizing oilfield wastes, (3) determining the nature and extent of soil and groundwater pollution, (4) preparing a remedial action plan, (5) assessing the viability of various remediation options, and (6) preparing health and safety plan. 12 refs., 2 tabs., 2 figs

  1. Heavy Metals in Contaminated Soils: A Review of Sources, Chemistry, Risks and Best Available Strategies for Remediation

    OpenAIRE

    Wuana, Raymond A.; Okieimen, Felix E.

    2011-01-01

    Scattered literature is harnessed to critically review the possible sources, chemistry, potential biohazards and best available remedial strategies for a number of heavy metals (lead, chromium, arsenic, zinc, cadmium, copper, mercury and nickel) commonly found in contaminated soils. The principles, advantages and disadvantages of immobilization, soil washing and phytoremediation techniques which are frequently listed among the best demonstrated available technologies for cleaning up heavy met...

  2. Plant-based remediation processes

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Dharmendra Kumar (ed.) [Belgian Nuclear Research Centre (SCK.CEN), Mol (Belgium). Radiological Impact and Performance Assessment Division

    2013-11-01

    A valuable source of information for scientists in the field of environmental pollution and remediation. Describes the latest biotechnological methods for the treatment of contaminated soils. Includes case studies and protocols. Phytoremediation is an emerging technology that employs higher plants for the clean-up of contaminated environments. Basic and applied research have unequivocally demonstrated that selected plant species possess the genetic potential to accumulate, degrade, metabolize and immobilize a wide range of contaminants. The main focus of this volume is on the recent advances of technologies using green plants for remediation of various metals and metalloids. Topics include biomonitoring of heavy metal pollution, amendments of higher uptake of toxic metals, transport of heavy metals in plants, and toxicity mechanisms. Further chapters discuss agro-technological methods for minimizing pollution while improving soil quality, transgenic approaches to heavy metal remediation and present protocols for metal remediation via in vitro root cultures.

  3. Particle morphology and mineral structure of heavy metal-contaminated kaolin soil before and after electrokinetic remediation.

    Science.gov (United States)

    Roach, Nicole; Reddy, Krishna R; Al-Hamdan, Ashraf Z

    2009-06-15

    This study aims to characterize the physical distribution of heavy metals in kaolin soil and the chemical and structural changes in kaolinite minerals that result from electrokinetic remediation. Three bench-scale electrokinetic experiments were conducted on kaolin that was spiked with Cr(VI) alone, Ni (II) alone, and a combination of Cr(VI), Ni(II) and Cd(II) under a constant electric potential of 1VDC/cm for a total duration of 4 days. Transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analyses were performed on the soil samples before and after electrokinetic remediation. Results showed that the heavy metal contaminant distribution in the soil samples was not observable using TEM and EDX. EDX detected nickel and chromium on some kaolinite particles and titanium-rich, high-contrast particles, but no separate phases containing the metal contaminants were detected. Small amounts of heavy metal contaminants that were detected by EDX in the absence of a visible phase suggest that ions are adsorbed to kaolinite particle surfaces as a thin coating. There was also no clear correlation between semiquantitative analysis of EDX spectra and measured total metal concentrations, which may be attributed to low heavy metal concentrations and small size of samples used. X-ray diffraction analyses were aimed to detect any structural changes in kaolinite minerals resulting from EK. The diffraction patterns showed a decrease in peak height with decreasing soil pH value, which indicates possible dissolution of kaolinite minerals during electrokinetic remediation. Overall this study showed that the changes in particle morphology were found to be insignificant, but a relationship was found between the crystallinity of kaolin and the pH changes induced by the applied electric potential.

  4. Particle morphology and mineral structure of heavy metal-contaminated kaolin soil before and after electrokinetic remediation

    International Nuclear Information System (INIS)

    Roach, Nicole; Reddy, Krishna R.; Al-Hamdan, Ashraf Z.

    2009-01-01

    This study aims to characterize the physical distribution of heavy metals in kaolin soil and the chemical and structural changes in kaolinite minerals that result from electrokinetic remediation. Three bench-scale electrokinetic experiments were conducted on kaolin that was spiked with Cr(VI) alone, Ni (II) alone, and a combination of Cr(VI), Ni(II) and Cd(II) under a constant electric potential of 1 VDC/cm for a total duration of 4 days. Transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analyses were performed on the soil samples before and after electrokinetic remediation. Results showed that the heavy metal contaminant distribution in the soil samples was not observable using TEM and EDX. EDX detected nickel and chromium on some kaolinite particles and titanium-rich, high-contrast particles, but no separate phases containing the metal contaminants were detected. Small amounts of heavy metal contaminants that were detected by EDX in the absence of a visible phase suggest that ions are adsorbed to kaolinite particle surfaces as a thin coating. There was also no clear correlation between semiquantitative analysis of EDX spectra and measured total metal concentrations, which may be attributed to low heavy metal concentrations and small size of samples used. X-ray diffraction analyses were aimed to detect any structural changes in kaolinite minerals resulting from EK. The diffraction patterns showed a decrease in peak height with decreasing soil pH value, which indicates possible dissolution of kaolinite minerals during electrokinetic remediation. Overall this study showed that the changes in particle morphology were found to be insignificant, but a relationship was found between the crystallinity of kaolin and the pH changes induced by the applied electric potential.

  5. Selection of innovative technologies for the remediation of soils contaminated with radioactive and mixed wastes

    International Nuclear Information System (INIS)

    Steude, J.; Tucker, B.

    1991-01-01

    The remediation of sites containing radioactive and mixed wastes is in a period of rapid growth. The state of the art of remediation is progressing to handle the shortcomings of conventional pump and treat or disposal technologies. The objective of this paper is to review the status of selected innovative technologies which treat soils contaminated with radioactive and mixed waste. Technologies are generally classified as innovative if they are fully developed, but lack sufficient cost or performance data for comparison with conventional technologies. The Environmental Protection Agency recommends inclusion of innovative technologies in the RI/FS screening process if there is reason to believe that they would offer advantages in performance, implementability, cost, etc. This paper serves as a compilation of the pertinent information necessary to gain an overview of the selected innovative technologies to aid in the RI/F'S screening process. The innovative technologies selected for evaluation are listed below. Bioremediation, although innovative, was not included due to the combination of the vast amount of literature on this subject and the limited scope of this project. 1. Soil washing and flushing; 2. Low temperature thermal treatment; 3. Electrokinetics; 4. Infrared incineration; 5. Ultrasound; 6. In situ vitrification; 7. Soil vapor extraction; 8. Plasma torch slagging; 9. In situ hot air/steam extraction; 10. Cyclone reactor treatment; 11. In situ radio frequency; 12. Vegetative radionuclide uptake; and 13. In situ soil heating. The information provided on each technology includes a technical description, status, summary of results including types of contaminants and soils treated, technical effectiveness, feasibility and estimated cost

  6. Hybrid technologies for the remediation of Diesel fuel polluted soil

    Energy Technology Data Exchange (ETDEWEB)

    Pazos, M.; Alcantara, M.T.; Rosales, E.; Sanroman, M.A. [Department of Chemical Engineering, University of Vigo (Spain)

    2011-12-15

    Diesel fuel may be released into soil due to anthropogenic activities, such as accidental spills or leaks in underground storage tanks or pipelines. Since diesel fuel is mainly composed of hydrophobic organic compounds, it has low water solubility. Therefore, treating contaminated areas with conventional techniques is difficult. In this study, electrokinetic treatment of soil contaminated with diesel fuel was carried out. Two different hybrid approaches to pollutant removal were tested. A surfactant was used as a processing fluid during electrokinetic treatment to increase desorption and the solubility of diesel fuel. Additionally, a hybrid technology combining a Fenton reaction and electrokinetic remediation (EK-Fenton) was tested in an attempt to generate favorable in situ degradation of pollutants. The efficiency of each treatment was determined based on diesel fuel removal. After 30 days of treatment, the highest removal of diesel fuel was found to be achieved with the EK-Fenton process. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Pig Manure Application for Remediation of Mine Soils in Murcia Province, SE Spain

    Directory of Open Access Journals (Sweden)

    A. Faz

    2008-01-01

    Full Text Available In southern Spain, specifically in Murcia Province, an increased pig population causes large amounts of slurry production that creates a very serious environmental concern. Our aim was to use this waste to reduce the acid mine drainage process, heavy metal mobilization, and to improve soil conditions to enhance plant establishment in mine soils. Pig manure, sewage sludge, and lime were used as soil amendments in a field experiment and in undisturbed soil column. Field experiments showed an increase in pH, total nitrogen, organic carbon, and carbonate contents; a reduction of diethylene-tetramine pentaacetic acid (DTPA– and water-extractable metals; and an improvement of plant establishment. The field studies showed that pig manure could be utilized to remediate polluted soils. Column studies in the laboratory showed that amendment of mine soil with pig manure initially increased soil pH from 2.21 to 6.34, promoted reduced conditions in the surface soil, and decreased the metal mobility. After 21 weeks, while the leachate was slightly acidic, however, the mobility of metals was substantially low. Additions of 7 and 14% of pig manure were insufficient to maintain a neutral pH in the leachate. Therefore, continuous application of the pig manure may be advised.

  8. Assessment of a remediation technique using the replacement of contaminated soils in kitchen gardens nearby a former lead smelter in Northern France.

    Science.gov (United States)

    Douay, F; Roussel, H; Pruvot, C; Loriette, A; Fourrier, H

    2008-08-15

    Vegetables cultivated in kitchen gardens that are strongly contaminated by heavy metals (Pb, Cd) may represent to consumers a means of exposure to these metals. This exposure is more problematic for those families that include a large quantity of home-grown vegetables in their diet. Researchers have shown that the majority of vegetables produced in kitchen gardens in the vicinity of the Metaleurop Nord smelter (Northern France) do not conform to European regulations. This study was carried out in three of these kitchen gardens. The concentrations of Cd and Pb in the topsoils were up to 24 and 3300 mg kg(-1) respectively. The method consisted of delineating a surface area of about 50 to 100 m(2) for each garden, then removing the contaminated soil and replacing it with a clean one. Seven species of vegetables were cultivated from 2003 to 2005 in the original contaminated soils and the remediated ones. The data showed a clear improvement of the quality of the vegetables cultivated in remediated soils, although 17% of them were still over the European legislative limits for foodstuffs. This suggested that there was a foliar contamination due to contaminated dust fallout coming from the closed smelter site and the adjacent polluted soils. In addition, the measurement of the Cd and Pb concentrations in the dust fallout showed that the substantial rise in metal concentrations in the remediated soil was not only due to atmospheric fallout. These results raise questions about possible technical, economic and sociological problems associated with this kind of remediation.

  9. Proceedings of the remediation technologies symposium 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This conference provided an opportunity for industry, practitioners, researchers and regulators to discuss technical issues in environmental remediation research and the latest innovations in soil and groundwater remediation. Cost effective in-situ and ex-situ soil reclamation strategies were presented along with groundwater and surface water remediation strategies in 13 sessions entitled: hydrocarbon contamination; salt management; liability management; chemical oxidation; light non-aqueous phase liquids (LNAPL); Montreal Center of Excellence in Brownfields Rehabilitation; Alberta government updates; phytoremediation; natural attenuation; Lake Wabamun; ex-situ remediation; in-situ remediation; and, miscellaneous issues. Technological solutions for erosion control and water clarification were highlighted. The conference featured 52 presentations, of which 17 have been catalogued separately for inclusion in this database. tabs., figs.

  10. [Bidens maximowicziana's adsorption ability and remediation potential to lead in soils].

    Science.gov (United States)

    Wang, Hong-qi; Li, Hua; Lu, Si-jin

    2005-11-01

    Bidens maximowicziana's adsorption ability and remediation potential to lead were studied. The results show: (1) The Bidens maximowicziana has a strong adsorption to lead, the concentration of lead in plants increased linearly with the increase of lead concentration in soil. Then maximum concentration was 1509.3 mg x kg(-1) in roots and 2164.7 mg x kg(-1) in shoots when lead concentration in soil was 2000 mg x L(-1); (2) The lead concentration distribution order in the Bidens maximorwicziana is: leaf>stem>root>seed, which indicate that Bidens maximowicziana has a strong ability to transfer lead; (3) Uptaking ability differes in different vegetal periods. Maximum lead uptaking rate occured in the period of blooming for 40-60 days, in which daily uptake capacity was 15.81 mg x (kg x d)(-1) in roots and 19.83 mg x (kg x d)(-1) in shoots respectively. It can be concluded that Bidens maximowicziana appeares to be a moderate Pb accumulator making it suitable for phytoremediation of Pb contaminated soil.

  11. Remediation of 20,000 m3 of hydrocarbon-impacted soil at a former well site using the biopile process

    Energy Technology Data Exchange (ETDEWEB)

    Bedard, G. [Biogenie Inc., Calgary, AB (Canada)

    2006-07-01

    The remediation of 20,000 m{sup 3} of hydrocarbon-impacted soil at a former well site using the biopile process was discussed. The site involved was an abandoned site located southwest from Red Deer, Alberta in an agricultural area. The presentation provided background on the site history and discussed an additional site assessment. The objectives of this assessment were to complete the delineation of the hydrocarbon plume; confirm the depth of impact identified in a previous environmental assessment; and, select the most efficient remediation strategy. The presentation also discussed findings of the Environmental Services Association (ESA). Site specific challenges that were addressed included proximity of land owners; lease slopes to a nearby river; large volume of impacted material; depth of impact; limited space available on-site; high concentrations of petroleum hydrocarbons (PHCs); segregation of impacted soil; and winter installation and start-up. The proposed strategy and its advantages as well as the methodology for the remediation strategy were all discussed. 5 tabs., 5 figs.

  12. In situ radio-frequency heating for soil remediation at a former service station: case study and general aspects

    Energy Technology Data Exchange (ETDEWEB)

    Huon, G.; Simpson, T.; Maini, G. [Ecologia Environmental Solutions Ltd., Sittingbourne, Kent (United Kingdom); Holzer, F.; Kopinke, F.D.; Roland, U. [Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Leipzig (Germany); Will, F. [Total UK, Watford (United Kingdom)

    2012-08-15

    In situ radio-frequency heating (ISRFH) was successfully applied during remediation of a former petrol station. Using a three-electrode array in combination with extraction wells for soil vapor extraction (SVE), pollution consisting mainly of benzene, toluene, ethylbenzene, xylenes, and mineral oil hydrocarbons (in total about 1100 kg) was eliminated from a chalk soil in the unsaturated zone. Specially designed rod electrodes allowed selective heating of a volume of approximately 480 m{sup 3}, at a defined depth, to a mean temperature of about 50 C. The heating drastically increased the extraction rates. After switching off ISRFH, SVE remained highly efficient for some weeks due to the heat-retaining properties of the soil. Comparison of an optimized regime of ISRFH/SVE with conventional ''cold'' SVE showed a reduction of remediation time by about 80 % while keeping the total energy consumption almost constant. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Electrokinetic remediation of contaminated soils: An update

    International Nuclear Information System (INIS)

    Lindgren, E.R.; Kozak, M.W.; Mattson, E.D.

    1992-01-01

    Electrokinetic remediation of chromium contaminated soil has been demonstrated for unsaturated 50-100 mesh sand with 10% moisture by weight. The initial region of sand contaminated with 100 ppm w chromate ions was completely cleansed of contamination. After 22 hours of treatment, chromate was found near the anode and apparently migrated at a rate of at least 0.40 cm/hr with a pore water current density of 2.26mA/cm 2 . An analogous run was made using the same sand and FD and C Red No. 40 as the contaminant at a molar concentration equivalent to the 100 ppm w Cr run. The position of the migrating dye was monitored photographically. After similar treatment conditions, the visual dye concentration profile exhibited characteristics similar to the chromate. The migration rate of the dye was slower than the chromate but the qualitative similarity of behavior in an electric field suggests the dye is an analog for chromate ions. The slower migration rate of the dye is not unexpected because the dye molecule is larger than chromate. The use of dye as an analog for chromate greatly accelerates the experimentation process in unsaturated soil because destructive sampling is not required to monitor the contaminant location. Experiments were also conducted to determine the effect of soil heterogeneities on the electrokinetic processes. Unsaturated sands in size fractions of 50-100 mesh (medium) and 100-200 mesh (fine) were studied both individually and in layers. The dye migration rate was accelerated in the tine sand and slowed in the medium sand of the layered experiment when compared with the corresponding individual experiments. This discrepancy was explained by estimating the current density in each layer which was proportionally higher in the fine layer and lower in the medium layer. These preliminary experiments illustrate the significant dependence of electromigration rates on current density. (author)

  14. Study of the potential of barnyard grass for the remediation of Cd- and Pb-contaminated soil.

    Science.gov (United States)

    Xu, Jianling; Cai, Qiongyao; Wang, Hanxi; Liu, Xuejun; Lv, Jing; Yao, Difu; Lu, Yue; Li, Wei; Liu, Yuanyuan

    2017-05-01

    In this study, the microwave digestion method was used to determine total cadmium (Cd) and lead (Pb) concentrations, the BCR method was used to determine different states of Cd and Pb, and atomic absorption spectroscopy (AAS) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to determine Cd and Pb concentrations in simulated soil and barnyard grass before and after planting barnyard grass to provide a theoretical basis for the remediation of Cd- and Pb-contaminated soil. The results showed that the bioconcentration factor changes with different Cd concentrations are relatively complex and that the removal rate increases regularly. The 100 mg kg -1 Cd treatment had the highest removal rate, which reached 36.66%. For Pb, the bioconcentration factor decreased and tended to reach equilibrium as the Pb concentration increased. The highest removal rate was 41.72% and occurred in the 500 mg kg -1 Pb treatment; however, this removal rate was generally lower than that of Cd. In addition, the reduction state had the highest change rate, followed by the residual, acid soluble and oxidation states. For Pb, the residual state has the highest change rate, followed by the acid soluble state, reduction state and oxidation state. In addition, a significant correlation was observed between the soil Pb and Cd concentrations and the concentrations of Pb and Cd that accumulated in the belowground biomass of the barnyard grass, but no significant correlation was observed between the soil Pb and Cd concentrations and the amounts of Pb and Cd that accumulated in the aboveground biomass of the barnyard grass. The highest transfer factor of Cd was 0.49, which occurred in the 5 mg kg -1 Cd treatment. The higher transfer factor of Pb was 0.48 in the 100 mg kg -1 Pb treatment. All of these factors indicate that the belowground biomass of barnyard grass plays a more important role in the remediation of Cd- and Pb-contaminated soils than the aboveground

  15. Terrestrial exposure of oilfield flowline additives diminish soil structural stability and remediative microbial function

    International Nuclear Information System (INIS)

    George, S.J.; Sherbone, J.; Hinz, C.; Tibbett, M.

    2011-01-01

    Onshore oil production pipelines are major installations in the petroleum industry, stretching many thousands of kilometres worldwide which also contain flowline additives. The current study focuses on the effect of the flowline additives on soil physico-chemical and biological properties and quantified the impact using resilience and resistance indices. Our findings are the first to highlight deleterious effect of flowline additives by altering some fundamental soil properties, including a complete loss of structural integrity of the impacted soil and a reduced capacity to degrade hydrocarbons mainly due to: (i) phosphonate salts (in scale inhibitor) prevented accumulation of scale in pipelines but also disrupted soil physical structure; (ii) glutaraldehyde (in biocides) which repressed microbial activity in the pipeline and reduced hydrocarbon degradation in soil upon environmental exposure; (iii) the combinatory effects of these two chemicals synergistically caused severe soil structural collapse and disruption of microbial degradation of petroleum hydrocarbons. - Highlights: → Effects of flowline additives on soil structure and microbial function highlighted. → Phosphonate salts (in scale inhibitor) were found to disrupt soil physical structure. → Glutaraldehyde (in biocides) caused significant reduction of hydrocarbon degradation in soil. → Flowline additive chemicals synergistically affects soil structure and remediative microbial function. - Scale inhibitor and biocide oilfield flowline additives interactively affect soil physical and microbial properties

  16. The Impacts of Thermal and Smouldering Remediation on Soil Properties Related to Rehabilitation and Plant Growth

    Science.gov (United States)

    Pape, A.; Knapp, C.; Switzer, C.

    2012-04-01

    Tens of thousands of sites worldwide are contaminated with toxic non-aqueous phase liquids (NAPLs) reducing their economic and environmental value. As a result a number of treatments involving heat and smouldering have been developed to desorb and extract or destroy these contaminants including; steam injection (treatments are efficient enough for the soil to be safe for use, but the heating may unintentionally reduce the capability of the soil to act as a growing media. To investigate the effects of elevated temperature soils samples were heated at fixed temperatures (ambient to 1000°C) for one hour or smouldered after artificial contamination. Temperatures up to 105°C resulted in very little change in soil properties but at 250°C nutrients became more available. At 500°C little organic matter or nitrogen remained in the soil and clay sized particles started to decompose and aggregate. By 1000°C total and available phosphorus were very low, cation exchange capacity had been reduced, pH had increased and the clay fraction had been completely lost. Similar changes were observed in smouldered soils with variations dependent upon remediation conditions. As a result the smouldered soils will require nutrient supplementation to facilitate plant growth. Nutrient addition will also improve the physical properties of the soil and serve to re-inoculate it with microbes, particularly if an organic source such as compost or sewage sludge is used. The soils may remain effective growing media during lower temperature treatments; however some sort of soil inoculant would also be beneficial as these temperatures are sufficient to sterilise the system, which may impact nutrient cycling. Further work involving months-long exposure to the elevated temperatures that are typical of thermal remediation would be necessary to evaluate these changes relative to treatment conditions. Using this information rehabilitation packages can be developed and tailored to specific treatments as

  17. Sorbent amendment as a remediation strategy to reduce PFAS mobility and leaching in a contaminated sandy soil from a Norwegian firefighting training facility.

    Science.gov (United States)

    Hale, Sarah E; Arp, Hans Peter H; Slinde, Gøril Aasen; Wade, Emma Jane; Bjørseth, Kamilla; Breedveld, Gijs D; Straith, Bengt Fredrik; Moe, Kamilla Grotthing; Jartun, Morten; Høisæter, Åse

    2017-03-01

    Aqueous film-forming foams (AFFF) containing poly- and perfluoroalkyl substances (PFAS) used for firefighting have led to the contamination of soil and water at training sites. The unique physicochemical properties of PFAS results in environmental persistency, threatening water quality and making remediation of such sites a necessity. This work investigated the role of sorbent amendment to PFAS contaminated soils in order to immobilise PFAS and reduce mobility and leaching to groundwater. Soil was sampled from a firefighting training facility at a Norwegian airport and total and leachable PFAS concentrations were quantified. Perfluorooctanesulfonic acid (PFOS) was the most dominant PFAS present in all soil samples (between 9 and 2600 μg/kg). Leaching was quantified using a one-step batch test with water (L/S 10). PFOS concentrations measured in leachate water ranged between 1.2 μg/L and 212 μg/L. Sorbent amendment (3%) was tested by adding activated carbon (AC), compost soil and montmorillonite to selected soils. The extent of immobilisation was quantified by measuring PFAS concentrations in leachate before and after amendment. Leaching was reduced between 94 and 99.9% for AC, between 29 and 34% for compost soil and between 28 and 40% for the montmorillonite amended samples. Sorbent + soil/water partitioning coefficients (K D ) were estimated following amendment and were around 8 L/kg for compost soil and montmorillonite amended soil and ranged from 1960 to 16,940 L/kg for AC amended soil. The remediation of AFFF impacted soil via immobilisation of PFAS following sorbent amendment with AC is promising as part of an overall remediation strategy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Intrinsic remediation of JP-4 fuel in soil and ground water

    International Nuclear Information System (INIS)

    Schmithorst, W.L. Jr.; Vardy, J.A.

    1995-01-01

    Intrinsic remediation methods were employed to remediate soil and ground water contaminated by JP-4 fuel at the United States Coast Guard (USCG) Support Center facility in Elizabeth City, North Carolina. By the time the release was discovered, non-aqueous phase JP-4 fuel was detected in ground water over an area of approximately 8,000 square feet. In addition, concentrations of dissolved BTEX in ground water exceeded 5,000 microg/L. Tight clays present in the upper two meters of the aquifer, underlain by highly transmissive sands, prevented remediation of the JP-4 by conventional treatment methods. Therefore, a system of air injection and air extraction wells were installed that simultaneously depressed the water table and extracted hydrocarbon vapors. The conceptual idea, developed by the EPA RS Kerr Environmental Laboratory (RSKERL) in Ada, Oklahoma, is to stimulate rapid intrinsic biodegradation of the JP-4 fuel compounds. Subsequent biorespiration measurements indicated that the fuel compounds were being rapidly biodegraded. Upon removal of the non aqueous JP-4 compounds, an investigation was conducted to determine if the aquifer had an adequate assimilative capacity to support natural aerobic and anaerobic biodegradation of the contaminants. Analysis of ground water samples collected using a cone penetrometer and a direct-push sampling device indicate a sufficient concentration of electron acceptors to support natural biodegradation of the JP-4 compounds

  19. Rural areas affected by the Chernobyl accident: Radiation exposure and remediation strategies

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P., E-mail: Jacob@helmholtz-muenchen.de [Helmholtz Zentrum Muenchen, Institute of Radiation Protection, 85764 Neuherberg (Germany); Fesenko, S. [International Atomic Energy Agency, Vienna (Austria); Bogdevitch, I. [Scientific Research State Enterprise ' Institute for Soil Science and Agrochemistry' , Minsk (Belarus); Kashparov, V. [Ukrainian Institute of Agricultural Radiology, Chabany (Ukraine); Sanzharova, N. [Russian Institute of Agricultural Radiology and Radioecology, Obninsk (Russian Federation); Grebenshikova, N. [Institute of Radiology, Gomel (Belarus); Isamov, N. [Russian Institute of Agricultural Radiology and Radioecology, Obninsk (Russian Federation); Lazarev, N. [Ukrainian Institute of Agricultural Radiology, Chabany (Ukraine); Panov, A. [Russian Institute of Agricultural Radiology and Radioecology, Obninsk (Russian Federation); Ulanovsky, A. [Helmholtz Zentrum Muenchen, Institute of Radiation Protection, 85764 Neuherberg (Germany); Zhuchenko, Y. [Institute of Radiology, Gomel (Belarus); Zhurba, M. [Ukrainian Institute of Agricultural Radiology, Chabany (Ukraine)

    2009-12-15

    Main objectives of the present work were to develop an internationally agreed methodology for deriving optimized remediation strategies in rural areas that are still affected by the Chernobyl accident, and to give an overview of the radiological situation in the three affected countries, Belarus, Russia and Ukraine. Study settlements were defined by having in 2004 less than 10,000 inhabitants and official dose estimates exceeding 1 mSv. Data on population, current farming practices, contamination of soils and foodstuffs, and remedial actions previously applied were collected for each of such 541 study settlements. Calculations of the annual effective dose from internal radiation were validated with extensive data sets on whole body counter measurements. According to our calculations for 2004, in 290 of the study settlements the effective dose exceeded 1 mSv, and the collective dose in these settlements amounted to about 66 person-Sv. Six remedial actions were considered: radical improvement of grassland, application of ferrocyn to cows, feeding pigs with uncontaminated fodder before slaughter, application of mineral fertilizers for potato fields, information campaign on contaminated forest produce, and replacement of contaminated soil in populated areas by uncontaminated soil. Side effects of the remedial actions were quantified by a 'degree of acceptability'. Results are presented for two remediation strategies, namely, Strategy 1, in which the degree of acceptability was given a priority, and Remediation Strategy 2, in which remedial actions were chosen according to lowest costs per averted dose only. Results are highly country-specific varying from preference for soil replacement in populated areas in Belarus to preference for application of ferrocyn to cows in Ukraine. Remedial actions in 2010 can avert a large collective dose of about 150 person-Sv (including averted doses, which would be received in the following years). Nevertheless, the number of

  20. Fiscal 1994 survey report. Part 2. Study on soil environment remediation system using ecological information and functions; 1994 nendo seitaikei joho to seitaikei kino ni yoru dojo kankyo fukugen system no chosa hokokusho. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    A survey is conducted of the feasibility of soil environment remediation through detecting contamination of soil and changes in ecosystems caused by industrial activities, with attention paid to biological antagonists. In this fiscal year, based on the results of surveys conducted in the past, studies are continued mainly on hypersensitive biosensing technology using ecosystem functions, remote sensing technology to monitor the terrestrial vegetation and soil environment over wide areas, and soil environment remediation technology using biological antagonists and vegetation. In consideration of Europe's long experience in this field, seven organizations known for their accomplishments are visited, where interviews are held. There is a close relationship between soil environments and ecosystems, and ecosystems are provided not only with information on changes in soil environments but also with functions to remedy soil environments by minimizing secondary contamination. To put such information and functions to practical use, element technologies are indispensable, including hypersensitive soil environment biosensors and environmental remediation by identification and isolation of biological information carrying substances and by vegetation. Proposed in this report is a project for soil remediation by use of biological information and functions and for elucidation of biological antagonists. (NEDO)