Bioremediation of soils contaminated with fuel oils

International Nuclear Information System (INIS)

Baker, K.H.; Herson, D.S.; Vercellon-Smith, P.; Cronce, R.C.

1991-01-01

A utility company discovered soils in their plant contaminated with diesel fuel and related fuel oils (300-450 ppm). The soils were excavated and removed to a concrete pad for treatment. The authors conducted laboratory studies to determine if biostimulation or bioaugmentation would be appropriate for treating the soils. Microbial numbers and soil respiration were monitored in microcosms supplemented with: (1) organic nutrients, (2) inorganic nutrients, and (3) inorganic nutrients plus additional adapted microorganisms. Their studies indicated that biostimulation via the addition of inorganic nutrients would be appropriate at this site. Treatment cells for the contaminated soils were constructed. Initial data indicates that a 35% reduction in the concentration of contaminants has occurred within the first month of operation

Soil sealing degree as factor influencing urban soil contamination with polycyclic aromatic hydrocarbons (PAHs

Directory of Open Access Journals (Sweden)

Mendyk Łukasz

2016-03-01

Full Text Available The objective of the study was to determine role of soil sealing degree as the factor influencing soil contamination with polycyclic aromatic hydrocarbons (PAHs. The study area included four sampling sites located within the administrative boundaries of the Toruń city, Poland. Sampling procedure involved preparing soil pits representing three examples of soil sealing at each site: non-sealed soil as a control one (I and two degrees of soil sealing: semi-pervious surface (II and totally impervious surface (III. Together with basic properties defined with standard procedures (particle size distribution, pH, LOI, content of carbonates content of selected PAHs was determined by dichloromethane extraction using gas chromatography with mass spectrometric detection (GC-MS. Obtained results show that urban soils in the city of Toruń are contaminated with polycyclic aromatic hydrocarbons. Soil sealing degree has a strong influence on the soil contamination with polycyclic aromatic hydrocarbons. Totally sealed soils are better preserved from atmospheric pollution including PAHs. Combustion of grass/wood/coal was the main source of determined PAHs content in examined soils.

Radionuclide contaminated soil: Laboratory study and economic analysis of soil washing. Final report

International Nuclear Information System (INIS)

Fuhrmann, M.; Zhou, H.; Patel, B.; Bowerman, B.; Brower, J.

1996-01-01

The objective of the work discussed in this report is to determine if soil washing is a feasible method to remediate contaminated soils from the Hazardous Waste Management Facility (HWMF) at Brookhaven National Laboratory (BNL). The contaminants are predominantly Cs-137 and Sr-90. The authors have assumed that the target activity for Cs-137 is 50 pCi/g and that remediation is required for soils having greater activities. Cs-137 is the limiting contaminant because it is present in much greater quantities than Sr-90. This work was done in three parts, in which they: estimated the volume of contaminated soil as a function of Cs-137 content, determined if simple removal of the fine grained fraction of the soil (the material that is less than 0.063 mm) would effectively reduce the activity of the remaining soil to levels below the 50 pCi/g target, assessed the effectiveness of chemical and mechanical (as well as combinations of the two) methods of soil decontamination. From this analysis the authors were then able to develop a cost estimate for soil washing and for a baseline against which soil washing was compared

Evaluation of soil flushing of complex contaminated soil: An experimental and modeling simulation study

Energy Technology Data Exchange (ETDEWEB)

Yun, Sung Mi; Kang, Christina S. [Department of Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Kim, Jonghwa [Department of Industrial Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Kim, Han S., E-mail: hankim@konkuk.ac.kr [Department of Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)

2015-04-28

Highlights: • Remediation of complex contaminated soil achieved by sequential soil flushing. • Removal of Zn, Pb, and heavy petroleum oils using 0.05 M citric acid and 2% SDS. • Unified desorption distribution coefficients modeled and experimentally determined. • Nonequilibrium models for the transport behavior of complex contaminants in soils. - Abstract: The removal of heavy metals (Zn and Pb) and heavy petroleum oils (HPOs) from a soil with complex contamination was examined by soil flushing. Desorption and transport behaviors of the complex contaminants were assessed by batch and continuous flow reactor experiments and through modeling simulations. Flushing a one-dimensional flow column packed with complex contaminated soil sequentially with citric acid then a surfactant resulted in the removal of 85.6% of Zn, 62% of Pb, and 31.6% of HPO. The desorption distribution coefficients, K{sub Ubatch} and K{sub Lbatch}, converged to constant values as C{sub e} increased. An equilibrium model (ADR) and nonequilibrium models (TSNE and TRNE) were used to predict the desorption and transport of complex contaminants. The nonequilibrium models demonstrated better fits with the experimental values obtained from the column test than the equilibrium model. The ranges of K{sub Ubatch} and K{sub Lbatch} were very close to those of K{sub Ufit} and K{sub Lfit} determined from model simulations. The parameters (R, β, ω, α, and f) determined from model simulations were useful for characterizing the transport of contaminants within the soil matrix. The results of this study provide useful information for the operational parameters of the flushing process for soils with complex contamination.

Soil contamination issues at U.S. ports

International Nuclear Information System (INIS)

Rice, D.W.; Hagner, D.

1991-01-01

This paper reports that seven large and medium size west coast ports were surveyed during August 1990 to determine their involvement with hydrocarbon contaminated soils and activities associated with the characterization and remediation of these soils. All ports surveyed indicated that hey have hydrocarbon contaminated soil problems. Although other west coast ports do not have the scale of petroleum transfer and storage facilities that the Prot of Los Angeles has, all ports had tenants with bulk oil or fuel storage in aboveground tanks and were undertaking characterization and remediation work. Hydrocarbon contaminated soil problems were associated with these facilities or with decommissioned facilities of this type

Biological detoxification of a hydrocarbon contaminated soil

International Nuclear Information System (INIS)

Fabbri, F.; Lucchese, G.; Nardella, A.

2005-01-01

The soil quality of an industrial site chronically contaminated by 39000 mg/kg of oil was detrimentally affected. Soil treatments by bio-pile and land-farming resulted in a reduction of the level of contamination exceeding 90% of the original values, but without reaching regulatory limits. However, the bio-remediation treatments dramatically reduced the mobility of the contaminants and, accordingly, microbial tests clearly indicate that the soil quality improved to acceptable levels, similar to those typically observed in unaltered soils. Hydrocarbon mobility was estimated by the use of water and mild extractants (methanol and sodium dodecyl sulphate) to leach the contaminants from the soil; soil quality was evaluated by comparing the values of selected microbial and enzymatic parameters of the treated soil samples to reference values determined for natural soils. Microbial assessments included: measurement of the nitrification potential, dehydrogenase activity, measures of respiration and lipase activity, microbial counts (MPN on rich media) and Microtox TM assays of the water elutriate. Dermal absorption potential was evaluated using absorption on C 18 disks

Uptake by Plants of Radiostrontium from Contaminated Soils

DEFF Research Database (Denmark)

Andersen, A. J.

1965-01-01

In a recent report from this department it was shown that the extractability of radiostrontium from contaminated soil samples was effectively reduced by heat treatment and by the addition of phosphate to the soil. It was pointed out that, under emergency conditions, heat-treatment of the contamin......In a recent report from this department it was shown that the extractability of radiostrontium from contaminated soil samples was effectively reduced by heat treatment and by the addition of phosphate to the soil. It was pointed out that, under emergency conditions, heat......-treatment of the contaminated soil surface and heavy phosphate application might thus reduce the uptake by plants of radiostrontium more efficiently than liming, which is only effective in soils of low calcium status. In the investigation reviewed here the influence of heat treatment and superphosphate application on the plant...... uptake of radiostrontium was examined in pot experiments. For comparison the effect of applying calcium carbonate to the contaminated soil surface was also determined....

NCRP soil contamination task group

International Nuclear Information System (INIS)

Jacobs, D.G.

1987-01-01

The National Council of Radiation Protection and Measurements (NCRP) has recently established a Task Group on Soil Contamination to describe and evaluate the migration pathways and modes of radiation exposure that can potentially arise due to radioactive contamination of soil. The purpose of this paper is to describe the scientific principles for evaluation of soil contamination which can be used as a basis for derivation of soil contamination limits for specific situations. This paper describes scenarios that can lead to soil contamination, important characteristics of soil contamination, the subsequent migration pathways and exposure modes, and the application of principles in the report in deriving soil contamination limits. The migration pathways and exposure modes discussed in this paper include: direct radiation exposure; and exhalation of gases

Determination of solute organic concentration in contaminated soils using a chemical-equilibrium soil column system

DEFF Research Database (Denmark)

Gamst, Jesper; Kjeldsen, Peter; Christensen, Thomas Højlund

2007-01-01

using two soils with different content of organic carbon (f(oc) of 1.5 and 6.5%, respectively). A quadruple blind test of the ER-V system using glass beads in stead of soil showed an acceptable recovery (65-85%) of all of the 11 VOCs tested. Only for the most volatile compound (heptane, K-H similar...... to 80) an unacceptable recovery was found (9%). The contact time needed for obtaining chemical equilibrium was tested in the ER-H system by performing five test with different duration (1, 2, 4, 7 and 19 days) using the low organic carbon soil. Seven days of contact time appeared sufficient...... for determination of solute concentration in a contaminated soil were developed; (1) a chemical Equilibrium and Recirculation column test for Volatile organic chemicals (ER-V) and (2) a chemical Equilibrium and Recirculation column test for Hydrophobic organic chemicals (ER-H). The two test systems were evaluated...

Cadmium determination in lettuce grown in contaminated soil by INAAA and GFAAS

Energy Technology Data Exchange (ETDEWEB)

Armelin, Maria Jose A.; Maihara, Vera A.; Saiki, Mitiko, E-mail: marmelin@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Trevizam, Anderson R.; Silva, Maria Ligia S. [Universidade Estadual do Centro Oeste (UNICENTRO), Guarapuava, PR (Brazil); Muraoka, Takashi, E-mail: muraoka@cena.usp.b [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)

2011-07-01

Although Cd is not essential for the mammalian organism, it follows in body the same pathways of essential elements such as zinc and copper. There is evidence that the Cd induced reduction of Ca absorption, may lead to the development of osteoporosis. Anthropogenic activities associated with industrial activities, mining and use of fertilizers, limestone pesticides in agriculture are the main sources of Cd enrichment in soils. Due to the possibility that Cd being absorbed by plants and through them to reach the food chain, interest has increased in regard to developing techniques for remediation of contaminated sites. The addition of substances capable of immobilizing the toxic elements from the soil is a procedure that has been used for remediation of contaminated sites. The function of these substances is to reduce the mobility and bioavailability of potentially toxic elements in the soil. In this study, five doses of phosphorus as triple phosphorus were used in a number of lettuce plants grown in contaminated soil. The concentration of Cd present in lettuce leaves treated with phosphate was compared with the Cd absorbed by the control plant leaves. Instrumental Neutron Activation Analysis (INAA) and Graphite-Furnace Absorption Atomic Spectrometry (GFAAS) were the analytical methods used to determine Cd contents in lettuce leaves. The objective was to evaluate the performance of the employed analytical methods: INAA and GFAAS in the assessment of the efficiency of phosphorus treatments to reduce the Cd concentrations in leaves of lettuce. Results obtained indicated that both analytical methods were efficient to discriminate the response of Cd concentration in lettuce as a function of soil treatment with phosphorus. Although INAA has shown a positive performance in this study, GFAAS seemed more appropriate because its sensitivity was much higher than that obtained by INAA, in the experimental conditions. (author)

Cadmium determination in lettuce grown in contaminated soil by INAAA and GFAAS

International Nuclear Information System (INIS)

Armelin, Maria Jose A.; Maihara, Vera A.; Saiki, Mitiko; Trevizam, Anderson R.; Silva, Maria Ligia S.; Muraoka, Takashi

2011-01-01

Although Cd is not essential for the mammalian organism, it follows in body the same pathways of essential elements such as zinc and copper. There is evidence that the Cd induced reduction of Ca absorption, may lead to the development of osteoporosis. Anthropogenic activities associated with industrial activities, mining and use of fertilizers, limestone pesticides in agriculture are the main sources of Cd enrichment in soils. Due to the possibility that Cd being absorbed by plants and through them to reach the food chain, interest has increased in regard to developing techniques for remediation of contaminated sites. The addition of substances capable of immobilizing the toxic elements from the soil is a procedure that has been used for remediation of contaminated sites. The function of these substances is to reduce the mobility and bioavailability of potentially toxic elements in the soil. In this study, five doses of phosphorus as triple phosphorus were used in a number of lettuce plants grown in contaminated soil. The concentration of Cd present in lettuce leaves treated with phosphate was compared with the Cd absorbed by the control plant leaves. Instrumental Neutron Activation Analysis (INAA) and Graphite-Furnace Absorption Atomic Spectrometry (GFAAS) were the analytical methods used to determine Cd contents in lettuce leaves. The objective was to evaluate the performance of the employed analytical methods: INAA and GFAAS in the assessment of the efficiency of phosphorus treatments to reduce the Cd concentrations in leaves of lettuce. Results obtained indicated that both analytical methods were efficient to discriminate the response of Cd concentration in lettuce as a function of soil treatment with phosphorus. Although INAA has shown a positive performance in this study, GFAAS seemed more appropriate because its sensitivity was much higher than that obtained by INAA, in the experimental conditions. (author)

CONTAMINATED SOIL VOLUME ESTIMATE TRACKING METHODOLOGY

International Nuclear Information System (INIS)

Durham, L.A.; Johnson, R.L.; Rieman, C.; Kenna, T.; Pilon, R.

2003-01-01

The U.S. Army Corps of Engineers (USACE) is conducting a cleanup of radiologically contaminated properties under the Formerly Utilized Sites Remedial Action Program (FUSRAP). The largest cost element for most of the FUSRAP sites is the transportation and disposal of contaminated soil. Project managers and engineers need an estimate of the volume of contaminated soil to determine project costs and schedule. Once excavation activities begin and additional remedial action data are collected, the actual quantity of contaminated soil often deviates from the original estimate, resulting in cost and schedule impacts to the project. The project costs and schedule need to be frequently updated by tracking the actual quantities of excavated soil and contaminated soil remaining during the life of a remedial action project. A soil volume estimate tracking methodology was developed to provide a mechanism for project managers and engineers to create better project controls of costs and schedule. For the FUSRAP Linde site, an estimate of the initial volume of in situ soil above the specified cleanup guidelines was calculated on the basis of discrete soil sample data and other relevant data using indicator geostatistical techniques combined with Bayesian analysis. During the remedial action, updated volume estimates of remaining in situ soils requiring excavation were calculated on a periodic basis. In addition to taking into account the volume of soil that had been excavated, the updated volume estimates incorporated both new gamma walkover surveys and discrete sample data collected as part of the remedial action. A civil survey company provided periodic estimates of actual in situ excavated soil volumes. By using the results from the civil survey of actual in situ volumes excavated and the updated estimate of the remaining volume of contaminated soil requiring excavation, the USACE Buffalo District was able to forecast and update project costs and schedule. The soil volume

Contaminant Gradients in Trees: Directional Tree Coring Reveals Boundaries of Soil and Soil-Gas Contamination with Potential Applications in Vapor Intrusion Assessment.

Science.gov (United States)

Wilson, Jordan L; Samaranayake, V A; Limmer, Matthew A; Schumacher, John G; Burken, Joel G

2017-12-19

Contaminated sites pose ecological and human-health risks through exposure to contaminated soil and groundwater. Whereas we can readily locate, monitor, and track contaminants in groundwater, it is harder to perform these tasks in the vadose zone. In this study, tree-core samples were collected at a Superfund site to determine if the sample-collection location around a particular tree could reveal the subsurface location, or direction, of soil and soil-gas contaminant plumes. Contaminant-centroid vectors were calculated from tree-core data to reveal contaminant distributions in directional tree samples at a higher resolution, and vectors were correlated with soil-gas characterization collected using conventional methods. Results clearly demonstrated that directional tree coring around tree trunks can indicate gradients in soil and soil-gas contaminant plumes, and the strength of the correlations were directly proportionate to the magnitude of tree-core concentration gradients (spearman's coefficient of -0.61 and -0.55 in soil and tree-core gradients, respectively). Linear regression indicates agreement between the concentration-centroid vectors is significantly affected by in planta and soil concentration gradients and when concentration centroids in soil are closer to trees. Given the existing link between soil-gas and vapor intrusion, this study also indicates that directional tree coring might be applicable in vapor intrusion assessment.

Restoration of contaminated soils

International Nuclear Information System (INIS)

Miranda J, Jose Eduardo

2009-01-01

A great variety of techniques are used for the restoration of contaminated soils. The contamination is present by both organic and inorganic pollutants. Environmental conditions and soil characteristics should take into account in order to implement a remedial technique. The bioremediation technologies are showed as help to remove a variety of soil contaminants. (author) [es

Bioremediation of Pyrene-Contaminated Soils Using Biosurfactant

OpenAIRE

Jorfi; Rezaee; Jaafarzadeh; Esrafili; Akbari; Moheb Ali

2014-01-01

Background Polycyclic aromatic hydrocarbons (PAHs) are persistence organic chemicals with proved carcinogenic and mutagenic hazards. These compounds are usually adsorbed in soils in vicinity of oil and gas industries. Bioremediation of PAHs contaminated soils is difficult due to hydrophobic nature of PAHs. Objectives The main purpose of the current study was to determine the pyrene removal efficiency in synthetically contaminated ...

Bioremediation of Pyrene-Contaminated Soils Using Biosurfactant

Directory of Open Access Journals (Sweden)

Jorfi

2014-10-01

Full Text Available Background Polycyclic aromatic hydrocarbons (PAHs are persistence organic chemicals with proved carcinogenic and mutagenic hazards. These compounds are usually adsorbed in soils in vicinity of oil and gas industries. Bioremediation of PAHs contaminated soils is difficult due to hydrophobic nature of PAHs. Objectives The main purpose of the current study was to determine the pyrene removal efficiency in synthetically contaminated soil, using biosurfactant. Materials and Methods Four pure bacterial strains capable of pyrene degradation were isolated from contaminated soils via enrichment techniques. The soil samples were spiked with an initial pyrene concentration of 500 mg/kg and subjected to bioremediation using a mixed culture comprised of previously isolated strains, in addition to application of biosurfactant during 63 days. Results The pyrene removal efficiency in samples containing biosurfactant, without biosurfactant and controls, were 86.4%, 59.8% and 14%, respectively, after 63 days. The difference of pyrene removal efficiency between the biosurfactant-containing samples and the ones without it was significant (P < 0.05. Conclusions Application of rhamnolipid biosurfactant produced by Pseudomonas aeruginosa significantly improved pyrene removal in contaminated soils.

Hydrocarbon degradation potential in reference soils and soils contaminated with jet fuel

International Nuclear Information System (INIS)

Lee, R.F.; Hoeppel, R.

1991-01-01

Petroleum degradation in surface and subsurface soils is affected by such factors as moisture content, pH, soil type, soil organics, temperature, and oxygen concentrations. In this paper, the authors determine the degradation rates of 14 C-labeled hydrocarbons added to soils collected from a contaminated surface site, contaminated subsurface sites, and a clean reference site. The radiolabeled hydrocarbons used include benzene, toluene, naphthalene, 1-methynaphthalene, phenanthrene, fluorene, anthracene, chrysene, and hexadecane. Microbial degradation rates were based on determination of mineralization rates (production of 14 CO 2 ) of hydrocarbons that were added to soil samples. Since water was added and oxygen was not limiting, the hydrocarbon rates determined are likely to be higher than those occurring in situ. Using radiolabeled hydrocarbons, information can be provided on differences in the degradation rates of various petroleum compounds in different types of soils at a site, on possible production of petroleum metabolites in the soil, and on the importance of anaerobic petroleum degradation and the effects of nutrient, water, and surfactant addition on biodegradation rates

Soil contamination of plant surfaces from grazing and rainfall interactions

International Nuclear Information System (INIS)

Hinton, T.G.; Stoll, J.M.; Tobler, L.

1995-01-01

Contaminants often attach to soil particles, and their subsequent environmental transport is largely determined by processes that govern soil movement. We examined the influence of grazing intensity on soil contamination of pastures. Four different grazing densities of sheep were tested against an ungrazed control plot. Scandium concentrations were determined by neutron activation analysis and was used as a tracer of soil adhesion on vegetation. Soil loadings ( g soil kg -1 dry plant) increased 60% when grazing intensity was increased by a factor of four (p 0.003). Rain and wind removed soil from vegetation in the ungrazed control plots, but when grazing sheep were present, an increase in rain from 0.3 to 9.7 mm caused a 130% increase in soil contamination. Multiple regression was used to develop an equation that predicts soil loadings as a function of grazing density, rainfall and wind speed (p = 0.0001, r 2 = 0.78). The model predicts that if grazing management were to be used as a tool to reduce contaminant intake from inadvertent consumption of resuspended soil by grazing animals, grazing densities would have to be reduced 2.5 times to reduce soil loadings by 50%. (author)

Uptake of Organic Contaminants from Soil into Vegetables and Fruits

DEFF Research Database (Denmark)

Trapp, Stefan; Legind, Charlotte Nielsen

2011-01-01

Contaminants may enter vegetables and fruits by several pathways: by uptake with soil pore water, by diffusion from soil or air, by deposition of soil or airborne particles, or by direct application. The contaminant-specific and plantspecific properties that determine the importance of these path......Contaminants may enter vegetables and fruits by several pathways: by uptake with soil pore water, by diffusion from soil or air, by deposition of soil or airborne particles, or by direct application. The contaminant-specific and plantspecific properties that determine the importance...... of these pathways are described in this chapter. A variety of models have been developed, specific for crop types and with steady-state or dynamic solutions. Model simulations can identify sensitive properties and relevant processes. Persistent, polar (log KOW ... particles, or from air. Volatile contaminants have a low potential for accumulation because they quickly escape to air. Experimental data are listed that support these model predictions, but underline also the high variability of accumulation under field conditions. Plant uptake predictions are uncertain...

Protozoan predation in soil slurries compromises determination of contaminant mineralization potential

International Nuclear Information System (INIS)

Badawi, Nora; Johnsen, Anders R.; Brandt, Kristian K.; Sørensen, Jan; Aamand, Jens

2012-01-01

Soil suspensions (slurries) are commonly used to estimate the potential of soil microbial communities to mineralize organic contaminants. The preparation of soil slurries disrupts soil structure, however, potentially affecting both the bacterial populations and their protozoan predators. We studied the importance of this “slurry effect” on mineralization of the herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA, 14 C-labelled), focussing on the effects of protozoan predation. Mineralization of MCPA was studied in “intact” soil and soil slurries differing in soil:water ratio, both in the presence and absence of the protozoan activity inhibitor cycloheximide. Protozoan predation inhibited mineralization in dense slurry of subsoil (soil:water ratio 1:3), but only in the most dilute slurry of topsoil (soil:water ratio 1:100). Our results demonstrate that protozoan predation in soil slurries may compromise quantification of contaminant mineralization potential, especially when the initial density of degrader bacteria is low and their growth is controlled by predation during the incubation period. - Highlights: ► We studied the protozoan impact on MCPA mineralization in soil slurries. ► Cycloheximide was used as protozoan inhibitor. ► Protozoa inhibited MCPA mineralization in dilute topsoil slurry and subsoil slurry. ► Mineralization potentials may be underestimated when using soil slurries. - Protozoan predation may strongly bias the quantification of mineralization potential when performed in soil slurries, especially when the initial density of degrader bacteria is low such as in subsoil or very dilute topsoil slurries.

The Influence of Soil Chemical Factors on In Situ Bioremediation of Soil Contamination

Energy Technology Data Exchange (ETDEWEB)

Breedveld, Gijs D.

1997-12-31

Mineral oil is the major energy source in Western society. Production, transport and distribution of oil and oil products cause serious contamination problems of water, air and soil. The present thesis studies the natural biodegradation processes in the soil environment which can remove contamination by oil products and creosote. The main physical/chemical processes determining the distribution of organic contaminants between the soil solid, aqueous and vapour phase are discussed. Then a short introduction to soil microbiology and environmental factors important for biodegradation is given. There is a discussion of engineered and natural bioremediation methods and the problems related to scaling up laboratory experiments to field scale remediation. Bioremediation will seldom remove the contaminants completely; a residue remains. Factors affecting the level of residual contamination and the consequences for contaminant availability are discussed. Finally, the main findings of the work are summarized and recommendations for further research are given. 111 refs., 41 figs., 19 tabs.

Contaminant resorption during soil washing

International Nuclear Information System (INIS)

Gombert, D.

1993-01-01

To evaluate the applicability of soil washing to a specific site requires some basic research in how contaminants are bound. Much can be learned from sequential extraction methodology based on micronutrient bioavailability studies wherein the soil matrix is chemically dissected to selectively remove particular fixation mechanisms independently. This procedure uses a series of progressively more aggressive solvents to dissolve the principle phases that make up a soil, however, the published studies do not appear to consider the potential for a contaminant released from one type of site to resorb on another site during an extraction. This physical model assumes no ion exchange or adsorption at sites either previously occupied by other ions, or exposed by the dissolution. Therefore, to make engineering use of the sequential extraction data, the release of contamination must be evaluated relative to the effects of resorption. Time release studies were conducted to determine the optimum duration for extraction to maximize complete destruction of the target matrix fraction while minimizing contaminant resorption. Tests with and without a potassium brine present to inhibit cesium resorption indicated extraction efficiency could be enhanced by as much as a factor of ten using the brine

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

Uptake of Organic Contaminants from Soil into Vegetables and Fruits

DEFF Research Database (Denmark)

Trapp, Stefan; Legind, Charlotte Nielsen

2011-01-01

Contaminants may enter vegetables and fruits by several pathways: by uptake with soil pore water, by diffusion from soil or air, by deposition of soil or airborne particles, or by direct application. The contaminant-specific and plantspecific properties that determine the importance...... of these pathways are described in this chapter. A variety of models have been developed, specific for crop types and with steady-state or dynamic solutions. Model simulations can identify sensitive properties and relevant processes. Persistent, polar (log KOW contaminants have...... the highest potential for accumulation from soil, and concentrations in leaves may be several hundred times higher than in soil. However, for most contaminants the accumulation in vegetables or fruits is much lower. Lipophilic (log KOW > 3) contaminants are mainly transported to leaves by attached soil...

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

Enhanced bioremediation of PAH contaminated soils from coal processing sites

International Nuclear Information System (INIS)

Joshi, M.M.; Lee, S.

1995-01-01

The polycyclic aromatic hydrocarbons (PAH) are a potential hazard to health due to their carcinogenic, mutagenic nature and acute toxicity and there is an imminent need for remediation of PAH contaminated soils abounding the several coke oven and town gas sites. Aerobic biological degradation of PAHs is an innovative technology and has shown high decontamination efficiencies, complete mineralization of contaminants, and is environmentally safe. The present study investigates the remediation of PAH contaminated soils achieved using Acinetobacter species and fungal strain Phanerochaete Chrysosporium. The soil used for the experiments was an industrially contaminated soil obtained from Alberta Research Council (ARC) primary cleanup facility, Alberta, Canada. Soil characterization was done using High Performance Liquid Chromatography (HPLC) to qualitatively and quantitatively determine the contaminants in the soil. Artificially contaminated soil was also used for some experiments. All the experiments were conducted under completely mixed conditions with suitable oxygen and nutrient amendments. The removal efficiency obtained for various PAHs using the two microorganisms was compared

Ecotoxicological hazard assessment of hydrocarbon contaminated soils: A case study

International Nuclear Information System (INIS)

Roy, Y.; Pauwels, S.J.; Chasse, R.

1994-01-01

The Ecotoxicological Hazard Assessment (EHA) developed by the Quebec Ministry of Environment and Wildlife was used as part of the management scheme of contaminated soils from a former refinery. The study consists of assessing five types of soils (reference, heavily contaminated, slightly contaminated, thermally-treated, and biotreated) to determine their relative intrinsic hazard. During the exploratory activities a series of ten assessment endpoints where identified to support this typical EHA. During SOURCE characterization, the physicochemical make-up of the soils is described and the presence and concentrations of priority pollutants is determined. During FATE characterization, the potential for bioconcentration, mobility, and persistence of pollutants is determined. During EFFECTS characterization, the soils and their leachates are tested using standard terrestrial and aquatic bioassays. The data from the toxicological and analytical testing program are evaluated semi-quantitatively on the basis of a scoring system developed by consensus. The discussion will highlight how data are used within an EHA to streamline the decision-making process regarding the follow-up cleanup and disposal of contaminated soils

Prospects for separating heavy metal from contaminated soil

International Nuclear Information System (INIS)

Langen, M.; Hoberg, H.; Hamacher, B.

1994-01-01

For decades, large quantities of organic and inorganic pollutants have been brought into the soil as a result of the industrial operations of smelting and coking plants. This paper reports on the prospects of separating heavy metals from soil contaminated by smelting and coking plants by means of a physical/chemical washing procedure. Besides the description of virgin soil characteristics, cleaning results and process parameters of calssification, density separation and flotation processes are presented. It is shown that heavy metal pollution of virgin soil can be reduced by the classical process stages of soil washing. The metal content of virgin soil are critically assessed whereby the limits of the physical-chimical washing process will also be entered into. Emphasis is placed on the significance of the determination of limiting values for inorganic contamination, especially for soil contaminated with both organic and inorganic pollution. (orig.) [de

Bioremediation of contaminated soil

International Nuclear Information System (INIS)

Balba, M.T.; Ying, A.C.; McNeice, T.G.

1992-01-01

Microorganisms, especially bacteria, yeast and fungi are capable of degrading many kinds of xenobiotic compounds and toxic chemicals such as petroleum hydrocarbon compounds. These microorganisms are ubiquitous in nature and, despite their enormous versatility, there are numerous cases in which long-term contamination of soil and groundwater has been observed. The persistence of the contamination is usually caused by the inability of microorganisms to metabolize these compounds under the prevailing environmental condition. This paper reports on biological remediation of contaminated sites which can be accomplished by using naturally-occurring microorganisms to treat the contaminants. The development of a bioremediation program for a specific contaminated soil system usually includes: A thorough site/soil/waste characterization; Treatability studies

Plant tolerance to diesel minimizes its impact on soil microbial characteristics during rhizoremediation of diesel-contaminated soils

International Nuclear Information System (INIS)

Barrutia, O.; Garbisu, C.; Epelde, L.; Sampedro, M.C.; Goicolea, M.A.; Becerril, J.M.

2011-01-01

Soil contamination due to petroleum-derived products is an important environmental problem. We assessed the impacts of diesel oil on plants (Trifolium repens and Lolium perenne) and soil microbial community characteristics within the context of the rhizoremediation of contaminated soils. For this purpose, a diesel fuel spill on a grassland soil was simulated under pot conditions at a dose of 12,000 mg diesel kg -1 DW soil. Thirty days after diesel addition, T. repens (white clover) and L. perenne (perennial ryegrass) were sown in the pots and grown under greenhouse conditions (temperature 25/18 o C day/night, relative humidity 60/80% day/night and a photosynthetic photon flux density of 400 μmol photon m -2 s -1 ) for 5 months. A parallel set of unplanted pots was also included. Concentrations of n-alkanes in soil were determined as an indicator of diesel degradation. Seedling germination, plant growth, maximal photochemical efficiency of photosystem II (F v /F m ), pigment composition and lipophylic antioxidant content were determined to assess the impacts of diesel on the studied plants. Soil microbial community characteristics, such as enzyme and community-level physiological profiles, were also determined and used to calculate the soil quality index (SQI). The presence of plants had a stimulatory effect on soil microbial activity. L. perenne was far more tolerant to diesel contamination than T. repens. Diesel contamination affected soil microbial characteristics, although its impact was less pronounced in the rhizosphere of L. perenne. Rhizoremediation with T. repens and L. perenne resulted in a similar reduction of total n-alkanes concentration. However, values of the soil microbial parameters and the SQI showed that the more tolerant species (L. perenne) was able to better maintain its rhizosphere characteristics when growing in diesel-contaminated soil, suggesting a better soil health. We concluded that plant tolerance is of crucial importance for the

Risk assessment of soil contamination criteria

International Nuclear Information System (INIS)

King, C.M.; Marter, W.L.; Montaque, D.F.; Holton, G.A.

1987-06-01

Criteria have been developed to select radioactive and nonradioactive contaminants at waste sites detailed analysis and risk assessment. These criteria were based on soil and water quality guidelines developed by various government agencies to determine if the criteria were appropriate. We performed a risk assessment of a hypothetical site which contained radioactive and nonradioactive contaminants at levels equal to the criteria values. Risks to the public from atmospheric, surface water, and groundwater exposure pathways were examined. Health risks to the public from atmospheric releases of radioactive and nonradioactive materials from a waste at soil criteria contamination levels are low. Health risks to the maximally exposed individual to chemical carcinogens are considerably below traditional EPA action levels. And health risks to the maximally exposed individual to atmospherically released radioactive contaminants is 1.88 x 10 -7 , more than a factor of 5 less than 10 -6 . Based on our atmospheric exposure pathways analysis and risk assessment, the applied soil criteria are appropriate for screening out unimportant risk contributors to human health from atmospheric exposure pathways. 13 refs., 3 figs., 7 tabs

Natural revegetation of hydrocarbon-contaminated soil in semi-arid grasslands

International Nuclear Information System (INIS)

Bizecki Robson, D.; Knight, J. D.; Farrell, R. E.; Germida, J. J.

2004-01-01

Phytoremediation, or the use of plants to degrade and contain soil contaminants is considered a cost-effective decontaminant for sites contaminated by spills in the oil and gas producing areas of Western Canada. The objective of this study was to determine if contamination by hydrocarbons changes soil properties, species composition, and species abundance when compared with uncontaminated plots, and to identify species and functional groups unique to contaminated sites that may be further screened for their hydrocarbon-degrading ability. In pursuit of these objectives the effect of contamination on coverage, litter and bare ground was examined, differences in species composition between contaminated and uncontaminated sites were assessed, and the ability to fix nitrogen, and form mycorrhiza, life form, pollination mode, seed dispersal and reproduction mode of each species was determined. Results showed less vegetation and litter cover in contaminated plots, and significantly higher soil carbon to nitrogen ratios. Species diversity was also lower on contaminated sites, although species richness was not significantly different. Self-pollinated species were significantly more common on contaminated sites. Five grasses and three forbs were identified as tolerant of hydrocarbon-contaminated soils, with two grasses -- Agropyron smithii, and Agropyron trachycaulum -- being the most promising for reclamation. The low vegetation cover on contaminated plots is attributed to high pH and carbon to nitrogen ratios, and low nitrogen and phosphorus that results from soil disturbance. High electrical conductivity is also considered to adversely affect vegetation and litter cover on contaminated sites. 54 refs., 3 tabs., 1 fig

Natural revegetation of hydrocarbon-contaminated soil in semi-arid grasslands

Energy Technology Data Exchange (ETDEWEB)

Bizecki Robson, D.; Knight, J. D.; Farrell, R. E.; Germida, J. J. [University of Saskatchewan, Dept. of Soil Science, Saskatoon, SK (Canada)

2004-01-01

Phytoremediation, or the use of plants to degrade and contain soil contaminants is considered a cost-effective decontaminant for sites contaminated by spills in the oil and gas producing areas of Western Canada. The objective of this study was to determine if contamination by hydrocarbons changes soil properties, species composition, and species abundance when compared with uncontaminated plots, and to identify species and functional groups unique to contaminated sites that may be further screened for their hydrocarbon-degrading ability. In pursuit of these objectives the effect of contamination on coverage, litter and bare ground was examined, differences in species composition between contaminated and uncontaminated sites were assessed, and the ability to fix nitrogen, and form mycorrhiza, life form, pollination mode, seed dispersal and reproduction mode of each species was determined. Results showed less vegetation and litter cover in contaminated plots, and significantly higher soil carbon to nitrogen ratios. Species diversity was also lower on contaminated sites, although species richness was not significantly different. Self-pollinated species were significantly more common on contaminated sites. Five grasses and three forbs were identified as tolerant of hydrocarbon-contaminated soils, with two grasses -- Agropyron smithii, and Agropyron trachycaulum -- being the most promising for reclamation. The low vegetation cover on contaminated plots is attributed to high pH and carbon to nitrogen ratios, and low nitrogen and phosphorus that results from soil disturbance. High electrical conductivity is also considered to adversely affect vegetation and litter cover on contaminated sites. 54 refs., 3 tabs., 1 fig.

Bench Scale Treatability Studies of Contaminated Soil Using Soil Washing Technique

Directory of Open Access Journals (Sweden)

M. K. Gupta

2010-01-01

Full Text Available Soil contamination is one of the most widespread and serious environmental problems confronting both the industrialized as well as developing nations like India. Different contaminants have different physicochemical properties, which influence the geochemical reactions induced in the soils and may bring about changes in their engineering and environmental behaviour. Several technologies exist for the remediation of contaminated soil and water. In the present study soil washing technique using plain water with surfactants as an enhancer was used to study the remediation of soil contaminated with (i an organic contaminant (engine lubricant oil and (ii an inorganic contaminant (heavy metal. The lubricant engine oil was used at different percentages (by dry weight of the soil to artificially contaminate the soil. It was found that geotechnical properties of the soil underwent large modifications on account of mixing with the lubricant oil. The sorption experiments were conducted with cadmium metal in aqueous medium at different initial concentration of the metal and at varying pH values of the sorbing medium. For the remediation of contaminated soil matrices, a nonionic surfactant was used for the restoration of geotechnical properties of lubricant oil contaminated soil samples, whereas an anionic surfactant was employed to desorb cadmium from the contaminated soil matrix. The surfactant in case of soil contaminated with the lubricant oil was able to restore properties to an extent of 98% vis-à-vis the virgin soil, while up to 54% cadmium was desorbed from the contaminated soil matrix in surfactant aided desorption experiments.

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.

A petroleum contaminated soil bioremediation facility

Energy Technology Data Exchange (ETDEWEB)

Lombard, K.; Hazen, T.

1994-06-01

The amount of petroleum contaminated soil (PCS) at the Savannah River site (SRS) that has been identified, excavated and is currently in storage has increased several fold during the last few years. Several factors have contributed to this problem: (1) South Carolina Department of Health ad Environmental control (SCDHEC) lowered the sanitary landfill maximum concentration for total petroleum hydrocarbons (TPH) in the soil from 500 to 100 parts per million (ppm), (2) removal and replacement of underground storage tanks at several sites, (3) most recently SCDHEC disallowed aeration for treatment of contaminated soil, and (4) discovery of several very large contaminated areas of soil associated with leaking underground storage tanks (LUST), leaking pipes, disposal areas, and spills. Thus, SRS has an urgent need to remediate large quantities of contaminated soil that are currently stockpiled and the anticipated contaminated soils to be generated from accidental spills. As long as we utilize petroleum based compounds at the site, we will continue to generate contaminated soil that will require remediation.

A petroleum contaminated soil bioremediation facility

International Nuclear Information System (INIS)

Lombard, K.; Hazen, T.

1994-01-01

The amount of petroleum contaminated soil (PCS) at the Savannah River site (SRS) that has been identified, excavated and is currently in storage has increased several fold during the last few years. Several factors have contributed to this problem: (1) South Carolina Department of Health ad Environmental control (SCDHEC) lowered the sanitary landfill maximum concentration for total petroleum hydrocarbons (TPH) in the soil from 500 to 100 parts per million (ppm), (2) removal and replacement of underground storage tanks at several sites, (3) most recently SCDHEC disallowed aeration for treatment of contaminated soil, and (4) discovery of several very large contaminated areas of soil associated with leaking underground storage tanks (LUST), leaking pipes, disposal areas, and spills. Thus, SRS has an urgent need to remediate large quantities of contaminated soil that are currently stockpiled and the anticipated contaminated soils to be generated from accidental spills. As long as we utilize petroleum based compounds at the site, we will continue to generate contaminated soil that will require remediation

Contaminated soil concrete blocks

NARCIS (Netherlands)

de Korte, A.C.J.; Brouwers, Jos; Limbachiya, Mukesh C.; Kew, Hsein Y.

2009-01-01

According to Dutch law the contaminated soil needs to be remediated or immobilised. The main focus in this article is the design of concrete blocks, containing contaminated soil, that are suitable for large production, financial feasible and meets all technical and environmental requirements. In

Optimization of surfactant-aided remediation of industrially contaminated soils

International Nuclear Information System (INIS)

Joshi, M.M.; Lee, S.

1996-01-01

Soil matrices contaminated with polycyclic aromatic hydrocarbons (PAHs) abound at the sites of coke-oven gas plants, refineries, and many other major chemical industries. The removal of PAHs from soil using pure water, via soil washing (ex situ) or soil flushing (in situ), is quite ineffective due to their low solubility and hydrophobicity. However, addition of suitable surfactant(s) has been shown to increase the removal efficiency several fold. For the present work, the removal of PAHs occurring in industrially contaminated soil was studied. The objective was to use a nonionic surfactant solution for in situ soil flushing and to evaluate the optimal range of process parameters that can significantly increase the removal efficiency. The process parameters chosen were surfactant concentration, ratio of washing solution volume to soil weight, and temperature of washing solution. These parameters were found to have a significant effect on PAH removal from the contaminated soil and an optimal range was determined for each parameter under given washing conditions

Effect of soil contamination due to wastewater irrigation on total cesium as determined by destructive and nondestructive analytical techniques in some soils of egypt

International Nuclear Information System (INIS)

Abdel-Sabour, M.F.; Abdel-Lattif, A.

2005-01-01

Fifteen soil samples were chosen from different locations to represent different soils irrigated with different sources of contaminated wastewater (sewage and industrial effluent). Sequential extraction experiment was carried out to determine different forms of Cs in soils. Moreover, Soil samples were analyzed for total Cs using two analytical methods i.e. destructive wet digestion technique (Atomic Absorption Spectrometry, AAS or by summation of all sequential extracted fractions, SUM) and non-destructive technique (Neutron Activation Analysis, NAA). The aim of this study was to evaluate soil total Cs-forms (especially, bio-available fraction) as affected by soil pollution. Cesium was mostly concentrated in the residual fraction, and its values ranged from 57.4% to 82.9 % of total Cs in sandy soils and from 31.5% to 64.5 % of total Cs in tested clayey soil. Then organically bound Cs- fraction followed by Cs-occluded in Fe-Mn fraction, carbonate, exchangeable and water soluble fractions. Results suggested that, Cs level is affected by soil organic matter content, Fe-Mn oxides and clay content. The mobile Cs fraction (the sum of soluble and exchangeable fractions) ranged from 2% up to 9.9 % of total Cs in sandy soils. However, a higher value (9.82% to 15.31 %) could be observed in case of the tested clayey soils. Soils D and E were more contaminated than other tested soils. Data show obviously, that soil contaminated due to the irrigation with either sewage effluent or industrial wastewater has resulted in a drastic increase in both metal-organic and occluded in Fe and Mn oxide fractions followed by the carbonate fraction

CLOPYRALID DISSIPATION IN THE SOIL CONTAMINATED WITH HEAVY METALS

Directory of Open Access Journals (Sweden)

Mariusz Kucharski

2014-12-01

Full Text Available The aim of the studies was to determine the influence of copper and zinc contamination on clopyralid dissipation in soil. The experiment was carried out in laboratory conditions (plant growth chamber. Clopyralid was applied to three different soils [similar textures, pH, organic carbon content and contrasting copper and zinc content: soil natural contaminated with Cu and Zn (S1, soil with natural low Cu and Zn concentration (S2 and soil S21 prepared in the laboratory (S2 soil additionally contaminated with Cu and Zn salts in the amounts equivalent to contamination level of S1 soil]. Soil samples were taken for analyses for 1 hour (initial concentration and 2, 4, 8, 16, 32, 64 and 96 days after treatment. Clopyralid residue was analysed using GC/ECD (gas chromatography with electron capture detector. Good linearity was found between logarithmic concentration of clopyralid residues and time. The differences in Cu and Zn content influenced the clopyralid decay in soil. The values of DT50 obtained in the experiment ranged from 21 to 27 days. A high concentration of Cu and Zn in soil slowed down clopyralid degradation (the DT50 value was higher – 25–27 days.

Chemical fingerprinting of hydrocarbon-contamination in soil.

Science.gov (United States)

Boll, Esther S; Nejrup, Jens; Jensen, Julie K; Christensen, Jan H

2015-03-01

Chemical fingerprinting analyses of 29 hydrocarbon-contaminated soils were performed to assess the soil quality and determine the main contaminant sources. The results were compared to an assessment based on concentrations of the 16 priority polycyclic aromatic hydrocarbons pointed out by the U.S. Environmental Protection Agency (EPAPAH16) and total petroleum hydrocarbon (TPH). The chemical fingerprinting strategy proposed in this study included four tiers: (i) qualitative analysis of GC-FID chromatograms, (ii) comparison of the chemical composition of both un-substituted and alkyl-substituted polycyclic aromatic compounds (PACs), (iii) diagnostic ratios of selected PACs, and (iv) multivariate data analysis of sum-normalized PAC concentrations. The assessment criteria included quantitative analysis of 19 PACs and C1-C4 alkyl-substituted homologues of naphthalene, fluorene, dibenzothiophene, phenanthrene, pyrene, and chrysene; and 13 oxygenated polycyclic aromatic compounds (O-PACs). The chemical composition of un-substituted and alkyl-substituted PACs and visual interpretation of GC-FID chromatograms were in combination successful in differentiating pyrogenic and petrogenic hydrocarbon sources and in assessing weathering trends of hydrocarbon contamination in the soils. Multivariate data analysis of sum-normalized concentrations could as a stand-alone tool distinguish between hydrocarbon sources of petrogenic and pyrogenic origin, differentiate within petrogenic sources, and detect weathering trends. Diagnostic ratios of PACs were not successful for source identification of the heavily weathered hydrocarbon sources in the soils. The fingerprinting of contaminated soils revealed an underestimation of PACs in petrogenic contaminated soils when the assessment was based solely on EPAPAH16. As alkyl-substituted PACs are dominant in petrogenic sources, the evaluation of the total load of PACs based on EPAPAH16 was not representative. Likewise, the O-PACs are not

Effect Of Soil Contamination Due To Wastewater Irrigation On Total Co As Determined By Neutron Activation And Other Conventional Analytical Techniques In Some Soils Of Egypt

International Nuclear Information System (INIS)

Abdel-Sabour, M. F.; Al-Salama, Y. J.

2004-01-01

Fifteen soil samples were chosen from different locations (five different locations at north greater Cairo, Egypt) to represent different soils (alluvial and sandy) as well as different sources of contaminated wastewater (sewage and industrial effluent). Using sequential extraction technique (extracting the soil with different solutions, which is designed to separate metal fractions), Co was separated into six operationally defined fractions: water soluble, exchangeable, carbonate bound, Fe-Mn oxides bound, organic bound and residual fractions. Moreover, total-Co in soils as determined by three analytical methods (sum of sequential extracting, Atomic Absorption Spectrometry (AAS) and neutron activation analysis (NAA) techniques) were compared. Cobalt distribution between different extractants shows that the greatest amounts are found in the residual and Occluded in Fe and Mn-Oxides fractions followed by carbonate or organic fractions. In most cases the proportion of all tested Co-forms has increased in contaminated soil layers with higher enrichment in organically bound Co, occluded in Fe and Mn oxides, carbonate exchangeable and soluble fractions. Results indicate that soil properties have a significant role on Co fractions in soil. In the mean time, soil properties are affected by pollution factors such as source of pollution and load of pollution on the studied soil. Data showed that values of total Co determined by NAA method were always higher than the relevant values determined by AAS or those calculated after the sequential extraction method. (Authors)

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

Allowable residual contamination levels of radionuclides in soil from pathway analysis

International Nuclear Information System (INIS)

Nyquist, J.E.; Baes, C.F. III

1987-01-01

The Remedial Action Program (RAP) at Oak Ridge National Laboratory will include well drilling, facility upgrades, and other waste management operations likely to involve soils contaminated with radionuclides. A preliminary protocol and generalized criteria for handling contaminated soils is needed to coordinate and plan RAP activities, but there exists only limited information on contaminate nature and distribution at ORNL RAP sites. Furthermore, projections of long-term decommissioning and closure options for these sites are preliminary. They have adapted a pathway analysis model, DECOM, to quantify risks to human health from radionuclides in soil and used it to outline preliminary criteria for determining the fate of contaminated soil produced during RAP activities. They assumed that the site could be available for unrestricted use immediately upon decontamination. The pathways considered are consumption of food grown on the contaminated soil, including direct ingestion of soil from poorly washed vegetables, direct radiation from the ground surface, inhalation of resuspended radioactive soil, and drinking water from a well drilled through or near the contaminated soil. We will discuss the assumptions and simplifications implicit in DECOM, the site-specific data required, and the results of initial calculations for the Oak Ridge Reservation

Preliminary Experimental Analysis of Soil Stabilizers for Contamination Control

International Nuclear Information System (INIS)

Lagos, L.; Varona, J.; Zidan, A.; Gudavalli, R.; Wu, Kuang-His

2006-01-01

A major focus of Department of Energy's (DOE's) environmental management mission at the Hanford site involves characterizing and remediating contaminated soil and groundwater; stabilizing contaminated soil; remediating disposal sites; decontaminating and decommissioning structures, and demolishing former plutonium production process buildings, nuclear reactors, and separation plants; maintaining inactive waste sites; transitioning facilities into the surveillance and maintenance program; and mitigating effects to biological and cultural resources from site development and environmental cleanup and restoration activities. For example, a total of 470,914 metric tons of contaminated soil from 100 Areas remediation activities were disposed at the Environmental Restoration Disposal Facility (ERDF) during 2004. The Applied Research Center (ARC) at Florida International University (FIU) is supporting the Hanford's site remediation program by analyzing the effectiveness of several soil stabilizers (fixatives) for contamination control during excavation activities. The study is focusing on determining the effects of varying soil conditions, temperature, humidity and wind velocity on the effectiveness of the candidate stabilizers. The test matrix consists of a soil penetration-depth study, wind tunnel experiments for determination of threshold velocity, and temperature and moisture-controlled drying/curing experiments. These three set of experiments are designed to verify performance metrics, as well as provide insight into what fundamental forces are altered by the use of the stabilizer. This paper only presents the preliminary results obtained during wind tunnel experiments using dry Hanford soil samples (with 2.7% moisture by weight). These dry soil samples were exposed to varying wind speeds from 2.22 m/sec to 8.88 m/sec. Furthermore, airborne particulate data was collected for the dry Hanford soil experiments using an aerosol analyzer instrument. (authors)

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...

Application of Ultrasonic for Decontamination of Contaminated Soil - 13142

International Nuclear Information System (INIS)

Vasilyev, A.P.; Lebedev, N.M.; Savkin, A.E.

2013-01-01

The trials of soil decontamination were carried out with the help of a pilot ultrasonic installation in different modes. The installation included a decontamination bath equipped with ultrasonic sources, a precipitator for solution purification from small particles (less than 80 micrometer), sorption filter for solution purification from radionuclides washing out from soil, a tank for decontamination solution, a pump for decontamination solution supply. The trials were carried out on artificially contaminated sand with specific activity of 4.5 10 5 Bk/kg and really contaminated soil from Russian Scientific Center 'Kurchatovsky Institute' (RSC'KI') with specific activity of 2.9 10 4 Bk/kg. It was established that application of ultrasonic intensify the process of soil reagent decontamination and increase its efficiency. The decontamination factor for the artificially contaminated soil was ∼200 and for soil from RSC'KI' ∼30. The flow-sheet diagram has been developed for the new installation as well as determined the main technological characteristics of the equipment. (authors)

Chelate-assisted phytoextraction of lead from contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Cooper, E.M.; Sims, J.T.; Cunningham, S.D.; Huang, J.W.; Berti, W.R.

1999-12-01

Phytoextraction, a remediation strategy for lead (Pb)-contaminated soils that removes soil Pb through plant uptake and harvest, may be enhanced by use of synthetic chelates. The authors evaluated Pb desorption from four contaminated soils by seven chelates (CDTA, DTPA, EDDHA, EFTA, HEDTA, HEIDA, and NTA) at three rates. The three most effective chelates (CDTA, DTPA, and HEDTA) were used in greenhouse studies with an uncontaminated soil and a Pb-contaminated soil to determine the effect of chelate type and rate on growth, Pb uptake, and plant elemental composition. Lead desorption varied with chelate and soil and increased with chelate rate, averaging 948 mg Pb kg{sup {minus}1} at the 20 mmol kg{sup {minus}1} rate vs. 28 mg Pb kg{sup {minus}1} by the control. The general ranking of chelate effectiveness, based on total Pb desorbed, was HEDTA > CDTA > DTPA > EGTA > HEIDA > EDDHA {approximately} NTA. Plant uptake of Pb from the contaminated soil was enhanced by CDTA, DTPA, and HEDTA, but with even the most effective treatment (corn, high CDTA rate), the amount of Pb extracted by plants was rather low. Lead extractable by the Toxicity Characteristic Leaching Procedure (TCLP) was increased from 9 mg L{sup {minus}1} in the control to from 47 to 174 mg L{sup {minus}1} in soils treated with 20 mmol kg{sup {minus}1} CDTA or DTPA and chelates generally caused a shift in Pb from resistant to more soluble chemical fractions.

Enhancement of in situ Remediation of Hydrocarbon Contaminated Soil

Energy Technology Data Exchange (ETDEWEB)

Palmroth, M.

2006-07-01

oxidation of contaminants and by integrating the process to biological treatment, in which the formed degradation products can be biodegraded. Phytoremediation was used to remove fresh and aged petroleum hydrocarbons from soil, and modified FentonAEs reaction combined with biodegradation was used to remove aged creosote oil from soil. The effects of hydrocarbon aging, different plant species and soil amendments on the removal efficiency were studied in phytoremediation experiments. Lab-scale experiments were made with fresh diesel fuel, and a field study was made with aged hydrocarbons deriving from diesel fuel and lubricants. The used plant species were pine, poplar, a grass mixture and a legume mixture. The experiments with modified Fenton's treatment were carried out in soil columns, to which concentrated H{sub 2}O{sub 2} was added simulating in situ injection. Iron was not added since the soil was rich in iron. After FentonAEs treatment, the soil was incubated in serum bottles to determine the effects on bioavailability of PAHs by modified FentonAEs oxidation and to simulate the potential of intrinsic remediation. In addition to hydrocarbon analyses, the effects of both methods on soil microbial activities and toxicity were determined. In the presence of white clover and green pea, pine or poplar, 89 to 98 % of diesel fuel was removed, whereas the presence of grasses did not increase diesel fuel removal compared to treatment without plants, where up to 86 % of diesel fuel was removed. When diesel was applied to the trees for a second time, reduction in one month was 9 to 25 % higher than what was achieved after first month of first application. During the four growing season study with soil contaminated with aged hydrocarbon contaminants, the presence of vegetation did not increase hydrocarbon removal in unfertilised soil. Vegetation cover was denser in amended soil than in unfertilised soil. The addition of compost or NPK fertiliser enhanced hydrocarbon removal

Characterization and Low-Cost Remediation of Soils Contaminated by Timbers in Community Gardens.

Science.gov (United States)

Heiger-Bernays, W; Fraser, A; Burns, V; Diskin, K; Pierotti, D; Merchant-Borna, K; McClean, M; Brabander, D; Hynes, H P

2009-01-01

Urban community gardens worldwide provide significant health benefits to those gardening and consuming fresh produce from them. Urban gardens are most often placed in locations and on land in which soil contaminants reflect past practices and often contain elevated levels of metals and organic contaminants. Garden plot dividers made from either railroad ties or chromated copper arsenate (CCA) pressure treated lumber contribute to the soil contamination and provide a continuous source of contaminants. Elevated levels of polycyclic aromatic hydrocarbons (PAHs) derived from railroad ties and arsenic from CCA pressure treated lumber are present in the gardens studied. Using a representative garden, we 1) determined the nature and extent of urban community garden soil contaminated with PAHs and arsenic by garden timbers; 2) designed a remediation plan, based on our sampling results, with our community partner guided by public health criteria, local regulation, affordability, and replicability; 3) determined the safety and advisability of adding city compost to Boston community gardens as a soil amendment; and 4) made recommendations for community gardeners regarding healthful gardening practices. This is the first study of its kind that looks at contaminants other than lead in urban garden soil and that evaluates the effect on select soil contaminants of adding city compost to community garden soil.

Degradation of tetraethyllead in leaded gasoline contaminated and uncontaminated soils

International Nuclear Information System (INIS)

Ou, L.; Jing, W.; Thomas, J.; Mulroy, P.

1995-01-01

For over 50 years, since its introduction in 1923 by General Motors, tetraethyllead (TEL) was the major antiknock agent used in leaded gasoline. Since the middle of 1970, use of leaded gasoline in automobiles was gradually phased out. The main objective of this study is to determine the degradation rates and metabolites of TEL in gasoline contaminated and uncontaminated soils. TEL in uncontaminated soils disappeared rapidly. Ionic triethyllead (TREL) was the major organolead metabolite in these soils, with ionic diethyllead (DEL) being the minor product. Nonsterile soils, but not autoclaved soils, had limited capacity to mineralize 14 C-TEL to 14 CO 2 , H 2 0, and Pb 2+ . Unlike TEL in uncontaminated soils, petroleum hydrocarbons protected TEL in leaded gasoline contaminated soils from being degraded. Both disappearance and mineralization rates of TEL in leaded gasoline contaminated soils decreased with the increase in gasoline concentration. It appears that TEL in leaded gasoline contaminated soils is relatively stable until the level of petroleum hydrocarbons falls below a critical value. TEL is then rapidly degraded. Hydrocarbon degrading microorganisms may be involved, to some extent, in the degradation of TEL

Validated sampling strategy for assessing contaminants in soil stockpiles

International Nuclear Information System (INIS)

Lame, Frank; Honders, Ton; Derksen, Giljam; Gadella, Michiel

2005-01-01

Dutch legislation on the reuse of soil requires a sampling strategy to determine the degree of contamination. This sampling strategy was developed in three stages. Its main aim is to obtain a single analytical result, representative of the true mean concentration of the soil stockpile. The development process started with an investigation into how sample pre-treatment could be used to obtain representative results from composite samples of heterogeneous soil stockpiles. Combining a large number of random increments allows stockpile heterogeneity to be fully represented in the sample. The resulting pre-treatment method was then combined with a theoretical approach to determine the necessary number of increments per composite sample. At the second stage, the sampling strategy was evaluated using computerised models of contaminant heterogeneity in soil stockpiles. The now theoretically based sampling strategy was implemented by the Netherlands Centre for Soil Treatment in 1995. It was applied to all types of soil stockpiles, ranging from clean to heavily contaminated, over a period of four years. This resulted in a database containing the analytical results of 2570 soil stockpiles. At the final stage these results were used for a thorough validation of the sampling strategy. It was concluded that the model approach has indeed resulted in a sampling strategy that achieves analytical results representative of the mean concentration of soil stockpiles. - A sampling strategy that ensures analytical results representative of the mean concentration in soil stockpiles is presented and validated

Uranium-contaminated soil pilot treatment study

International Nuclear Information System (INIS)

Turney, W.R.J.R.; Mason, C.F.V.; Michelotti, R.A.

1996-01-01

A pilot treatment study is proving to be effective for the remediation of uranium-contaminated soil from a site at the Los Alamos National Laboratory by use of a two-step, zero-discharge, 100% recycle system. Candidate uranium-contaminated soils were characterized for uranium content, uranium speciation, organic content, size fractionization, and pH. Geochemical computer codes were used to forecast possible uranium leach scenarios. Uranium contamination was not homogenous throughout the soil. In the first step, following excavation, the soil was sorted by use of the ThemoNuclean Services segmented gate system. Following the sorting, uranium-contaminated soil was remediated in a containerized vat leach process by use of sodium-bicarbonate leach solution. Leach solution containing uranium-carbonate complexes is to be treated by use of ion-exchange media and then recycled. Following the treatment process the ion exchange media will be disposed of in an approved low-level radioactive landfill. It is anticipated that treated soils will meet Department of Energy site closure guidelines, and will be given open-quotes no further actionclose quotes status. Treated soils are to be returned to the excavation site. A volume reduction of contaminated soils will successfully be achieved by the treatment process. Cost of the treatment (per cubic meter) is comparable or less than other current popular methods of uranium-contamination remediation

Assessment of soil-gas, seep, and soil contamination at the North Range Road Landfill, Fort Gordon, Georgia, 2008-2009

Science.gov (United States)

Landmeyer, James E.; Falls, W. Fred; Ratliff, W. Hagan; Wellborn, John B.

2011-01-01

Soil gas, seeps, and soil were assessed for contaminants at the North Range Road Landfill at Fort Gordon, Georgia, from October 2008 to September 2009. The assessment included delineating organic contaminants present in soil-gas samples beneath the area estimated to be the landfill and in water samples collected from three seeps at the base of the landfill. Inorganic contaminants were determined in three seep samples and in soil samples. This assessment was conducted to provide environmental contamination data to Fort Gordon pursuant to requirements for the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process.

Phytoextraction of low level U-contaminated soil

International Nuclear Information System (INIS)

Vandenhove, H.A.; Hees, M. van

2002-01-01

The nuclear fuel cycle may be a source of environmental contamination. Uranium exploitation produces large quantities of wastes but also accidental spills at nuclear fuel production, reprocessing or waste treatment plants have led to soil contamination with uranium. U-contaminated soil is generally excavated, packaged and removed which is a costly enterprise. Soil washing has also shown promising in removing U from contaminated soil, but results in the generation of liquid wastes and the deterioration of soil properties. In contrast, phytoextraction, the use of plants to remove contaminants from polluted soil, allows for in situ treatment and does not generate liquid wastes. Furthermore, the contaminated site is covered by plants during phytoextraction and wind and water erosion will be reduced. The phytoextraction potential depends on the amount of radionuclides extracted and the biomass produced. Hyper-accumulating plants often have a low biomass production. Moreover, uranium soil-to-plant transfer factors (TF: ratio of U concentration in dry plant tissue to concentration in soil) rarely exceed a value of 0.1 gg -1 . With a TF of 0.1 gg -1 and a biomass yield of 15t dry weigh ha -1 only 0.1% of the soil uranium will be annually immobilised in the plant biomass. These figures clearly show that the phytoextraction option is not a feasible remediation option, unless the uranium bioavailability could be drastically increased. It was shown that citric acid addition to highly contaminated U contaminated soil increased the U-accumulation of Brassica juncea 1000-fold. The objective of the present paper is to find out if low level U contaminated soil can be phytoextracted in order to achieve proposed release limits

{sup 32}P-postlabeling determination of DNA adducts in the earthworm Lumbricus terrestris exposed to PAH-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Walsh, P. [Laval Univ. Research Center, Quebec (Canada)]|[Ministere de l`Environnement et de la Faune du Quebec (Canada); El Adlouni, C.; Mukhopadhyay, M.J.; Nadeau, D.; Poirier, G.G. [Laval Univ. Research Center, Quebec (Canada); Viel, G. [CreaLab., Quebec (Canada)

1995-05-01

The importance of the search for reliable biomarkers of DNA damage in environmental health assessment is well recognized by the scientific community and regulatory agencies. Among the major biomarkers of DNA damage is the measurement of DNA adducts in target cells or tissues. Up to now, DNA adduct determinations have been directed mostly toward human exposure to toxic substances from the workplace and environment. Moreover, techniques for measuring DNA adducts, and in particular the {sup 32}P-postlabelling technique, presented also the possibility of determining DNA adduct levels in endogenous animal populations exposed to polluted environments as early warning monitors of ecotoxicity. Soil contamination is becoming a major environmental issue. Therefore, numerous contaminated sites must now be remediated to protect human health and to permit new uses of these sites as agricultural, residential, or industrial areas. Fulfillment of this task requires standardized and sensitive bioassays to carry out site evaluations and to establish scientifically defensible soil quality criteria. To that effect, the earthworm appears to be one of the best organisms for use in soil toxicity evaluation. Earthworms are probably the most relevant soil species, representing 60 to 80% of the total animal biomass in soil. Present soil bioassays focus mostly on plant species with end points like seed germination, root elongation, seedling growth and seedling emergence, and on acute toxicity evaluation (re: LC 50) on the earthworm Eisenia fetida. As yet, a standardized soil invertebrate test for teratogenic or mutagenic end points has not been developed. In this paper, we report the feasibility of DNA adduct determination by {sup 32}P-postlabelling in the earthworm Lumbricus terrestris as a way to detect the presence of genotoxic substances in soils. 20 refs., 1 fig., 1 tab.

Soil washing and post-wash biological treatment of petroleum hydrocarbon contaminated soils

OpenAIRE

Bhandari, Alok

1992-01-01

A laboratory scale study was conducted to investigate the treatability of petroleum contaminated soils by soil washing and subsequent biological treatment of the different soil fractions. In addition to soils obtained from contaminated sites, studies were also performed on soils contaminated in the laboratory. Soil washing was performed using a bench-scale soil washing system. Washing was carried out with simultaneous fractionation of the bulk soil into sand, silt and clay fractions. Cl...

Plant uptake of radiocesium from contaminated soils

International Nuclear Information System (INIS)

Pipiska, M.; Lesny, J.; Hornik, M.; Augustin, J.

2004-01-01

Phytoextraction field experiments were conducted on soil contaminated with radiocesium to determine the capacity of autochthonous grasses and weeds to accumulate 137 Cs. The aim of the study was to evaluate the potential of spontaneously growing vegetation as a tool for decontamination of non-agricultural contaminated land. As a test field, the closed monitored area of the radioactive wastewater treatment plant of the Nuclear Power Plant in Jaslovskie Bohunice, Slovakia was used. contamination was irregularly distributed from the level of background to spots with maximal activity up to 900 Bq/g soil. Sequential extraction analysis of soil samples showed the following extractability of radiocesium (as percent of total): water 2 = 0.3-1.1%; 1M CH 3 COONa = 0.3-0.9%; 0.04 M NH 4 Cl (in 25% CH 3 COOH) = 0.9-1.4% and 30% H 2 O 2 - 0.02 M HNO 3 = 4.5-9.0%.Specific radioactivity of the most efficiently bioaccumulating plant species did not exceed 4.0 BqKg -1 (dry weight biomass). These correspond to the soil-to-plant transfer factor (TF) values up to 44.4x10 -4 BqKg -1 crop, d.w.)/(BqKg -1 soil d.w). Aggregated transfer factor (T ag ) of the average sample of the whole crop harvested from defined area was 0.5x10 -5 (Bqkg -1 d.w. crop)/(Bqm -2 soil). It can be concluded that low mobility of radiocesium in analysed soil type, confirmed by sequential extraction analyses, is the main hindrance for practical application for autochthonous plants as a phytoremediation tool for aged contaminated area of non-cultivated sites. Plant cover can efficiently serve only as a soil surface-stabilising layer, mitigating the migration of radiocesium into the surrounding environment. (author)

Quantifying Diffuse Contamination: Method and Application to Pb in Soil.

Science.gov (United States)

Fabian, Karl; Reimann, Clemens; de Caritat, Patrice

2017-06-20

A new method for detecting and quantifying diffuse contamination at the continental to regional scale is based on the analysis of cumulative distribution functions (CDFs). It uses cumulative probability (CP) plots for spatially representative data sets, preferably containing >1000 determinations. Simulations demonstrate how different types of contamination influence elemental CDFs of different sample media. It is found that diffuse contamination is characterized by a distinctive shift of the low-concentration end of the distribution of the studied element in its CP plot. Diffuse contamination can be detected and quantified via either (1) comparing the distribution of the contaminating element to that of an element with a geochemically comparable behavior but no contamination source (e.g., Pb vs Rb), or (2) comparing the top soil distribution of an element to the distribution of the same element in subsoil samples from the same area, taking soil forming processes into consideration. Both procedures are demonstrated for geochemical soil data sets from Europe, Australia, and the U.S.A. Several different data sets from Europe deliver comparable results at different scales. Diffuse Pb contamination in surface soil is estimated to be contamination sources and can be used to efficiently monitor diffuse contamination at the continental to regional scale.

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

Determining uranium speciation in contaminated soils by molecular spectroscopic methods: Examples from the Uranium in Soils Integrated Demonstration

International Nuclear Information System (INIS)

Allen, P.G.; Berg, J.M.; Chisholm-Brause, C.J.; Conradson, S.D.; Donohoe, R.J.; Morris, D.E.; Musgrave, J.A.; Tait, C.D.

1994-01-01

The US Department of Energy's former uranium production facility located at Fernald, OH (18 mi NW of Cincinnati) is the host site for an Integrated Demonstration for remediation of uranium-contaminated soils. A wide variety of source terms for uranium contamination have been identified reflecting the diversity of operations at the facility. Most of the uranium contamination is contained in the top ∼1/2 m of soil, but uranium has been found in perched waters indicating substantial migration. In support of the development of remediation technologies and risk assessment, we are conducting uranium speciation studies on untreated and treated soils using molecular spectroscopies. Untreated soils from five discrete sites have been analyzed. We have found that ∼80--90% of the uranium exists as hexavalent UO 2 2+ species even though many source terms consisted of tetravalent uranium species such as UO 2 . Much of the uranium exists as microcrystalline precipitates (secondary minerals). There is also clear evidence for variations in uranium species from the microscopic to the macroscopic scale. However, similarities in speciation at sites having different source terms suggest that soil and groundwater chemistry may be as important as source term in defining the uranium speciation in these soils. Characterization of treated soils has focused on materials from two sites that have undergone leaching using conventional extractants (e.g., carbonate, citrate) or novel chelators such as Tiron. Redox reagents have also been used to facilitate the leaching process. Three different classes of treated soils have been identified based on the speciation of uranium remaining in the soils. In general, the effective treatments decrease the total uranium while increasing the ratio of U(IV) to U(VI) species

Studies estimating the dermal bioavailability of polynuclear aromatic hydrocarbons from manufactured plant tar-contaminated soils

International Nuclear Information System (INIS)

Roy, T.A.; Krueger, A.J.; Taylor, B.B.; Mauro, D.M.; Goldstein, L.S.

1998-01-01

In vitro percutaneous absorption studies were performed with contaminated soils or organic extracts of contaminated soils collected at manufactured gas plant (MGP) sites. The MGP tar contaminated soils were found to contain a group of targeted polynuclear aromatic hydrocarbons (PAH) at levels ranging from 10 to 2400 mg/kg. The soil extracts contained target PAH at levels ranging from 12 000 - 34 000 mg/kg. Dermal penetration rates of target PAH from the MGP tar-contaminated soils/soil extracts were determined experimentally through human skin using 3 H-benzo(a)pyrene (BaP) as a surrogate. Results from three MGP sites showed reductions of 2-3 orders of magnitude in PAH absorption through human skin from the most contaminated soils in comparison to the soil extracts. Reduction in PAH penetration can be attributed to PAH concentration and (soil) matrix properties. PAH dermal flux values are used to determine site-specific dermally absorbed dose (DAD) and chronic daily intake (CDI) which are essential terms required to estimate risk associated with human exposure to MGP tar and MGP tar-contaminated soils. 21 refs., 4 figs., 3 tabs

Evaluation the Phytoremediation of Oil-contaminated Soils Around Isfahan Oil Refinery

Directory of Open Access Journals (Sweden)

Farida Iraji-Asiabadi

2016-07-01

Full Text Available Petroleum compounds are pollutants that most commonly occur in soils around oil refineries and that often find their ways into groundwater resources. Phytoremediation is a cost-effective alternative to physicochemical methods for oil-contaminated soil remediation, where feasible. In this study, a greenhouse experiment was conducted to evaluate the phytoremediation of oil-contaminated soils around Isfahan Oil Refinery. Four different plants (namely, sorghum, barley, agropyron, and festuca were initially evaluated in terms of their germinability in both contaminated and control (non-contaminated soils. Sorghum and barley (recording the highest germinability values were chosen as the species for use in the phytoremediation experiments. Shoot and root dry weights, total and oil-degrading bacteria counts, microbial activity, and total concentrations of petroleum hydrocarbons (TPHs were determined at harvest 120 days after planting. A significant difference was observed in the bacterial counts (total and oil-degrading bacteria between the planted soils and the control. In contaminated soils, a higher microbial activity was observed in the rhizosphere of the sorghum soil than in that of barley. TPHs concentration decreased by 52%‒64% after 120 days in contaminated soil in which sorghum and barley had been cultivated. This represented an improvement of 30% compared to the contaminated soil without plants. Based on the results obtained, sorghum and barley may be recommended for the removal of petro-contaminants in areas close to Isfahan Oil Refinery. Nevertheless, caution must be taken as such cultivated lands may need to be protected against grazing animals.

A decision-making process on cleanup of contaminated surface soil

International Nuclear Information System (INIS)

Yasuda, Hiroshi

1996-01-01

This study presents principles for determining derived intervention levels (DILs) for surface soil cleanup. The people concerned were divided into major three groups: residents, responsible parties, and cleanup workers; it was considered that each group has different interests. The DILs for soil cleanup were determined from the viewpoints of these three groups: safety of residence, advantages of the countermeasures, and safety of cleanup activities, respectively. An example process for determination of the DILs in accordance with the principles was also presented for a site contaminated by 137 Cs. This decision-making frame is expected to be applicable to other contaminants. (author)

Immobilization of uranium in contaminated soil by natural apatite addition

International Nuclear Information System (INIS)

Mrdakovic Popic, Jelena; Stojanovic, Mirjana; Milosevic, Sinisa; Iles, Deana; Zildzovic, Snezana

2007-01-01

Available in abstract form only. Full text of publication follows: The goal of this study was to evaluate the effectiveness of Serbian natural mineral apatite as soil additive for reducing the migration of uranium from contaminated sediments. In laboratory study we investigated the sorption properties of domestic apatite upon different experimental conditions, such as pH, adsorbent mass, reaction period, concentration of P 2 O 5 in apatite, solid/liquid ratio. In second part of study, we did the quantification of uranium in soil samples, taken from uranium mine site 'Kalna', by sequential extraction method. The same procedure was, also, used for uranium determination in contaminated soil samples after apatite addition, in order to determine the changes in U distribution in soil fraction. The obtained results showed the significant level of immobilization (96.7%) upon certain conditions. Increase of %P 2 O 5 in apatite and process of mechano-chemical activation led to increase of immobilization capacity from 17.50% till 91.64%. The best results for uranium binding were obtained at pH 5.5 and reaction period 60 days (98.04%) The sequential extraction showed the presence of uranium (48.2%) in potentially available soil fractions, but with the apatite addition uranium content in these fractions decreased (30.64%), what is considering environmental aspect significant fact. In situ immobilization of radionuclide using inexpensive sequestering agents, such as apatite, is very adequate for big contaminated areas of soil with low level of contamination. This investigation study on natural apatite from deposit 'Lisina' Serbia was the first one of this type in our country. Key words: apatite, uranium, immobilization, soil, contamination. (authors)

Bioremediation of petroleum contaminated soil

International Nuclear Information System (INIS)

Autry, A.R.; Ellis, G.M.

1992-01-01

This paper reports on bioremediation, which offers a cost-competitive, effective remediation alternative for soil contaminated with petroleum products. These technologies involve using microorganisms to biologically degrade organic constituents in contaminated soil. All bioremediation applications must mitigate various environmental rate limiting factors so that the biodegradation rates for petroleum hydrocarbons are optimized in field-relevant situations. Traditional bioremediation applications include landfarming, bioreactors, and composting. A more recent bioremediation application that has proven successful involves excavation of contaminated soil. The process involves the placement of the soils into a powerscreen, where it is screened to remove rocks and larger debris. The screened soil is then conveyed to a ribbon blender, where it is mixed in batch with nutrient solution containing nitrogen, phosphorus, water, and surfactants. Each mixed soil batch is then placed in a curing pile, where it remains undisturbed for the remainder of the treatment process, during which time biodegradation by naturally occurring microorganisms, utilizing biochemical pathways mediated by enzymes, will occur

Application of Ultrasonic for Decontamination of Contaminated Soil - 13142

Energy Technology Data Exchange (ETDEWEB)

Vasilyev, A.P. [JRC ' NIKIET' , Moscow (Russian Federation); Lebedev, N.M. [LLC ' Aleksandra-Plus' , Vologda (Russian Federation); Savkin, A.E. [SUE SIA ' Radon' , Moscow (Russian Federation)

2013-07-01

The trials of soil decontamination were carried out with the help of a pilot ultrasonic installation in different modes. The installation included a decontamination bath equipped with ultrasonic sources, a precipitator for solution purification from small particles (less than 80 micrometer), sorption filter for solution purification from radionuclides washing out from soil, a tank for decontamination solution, a pump for decontamination solution supply. The trials were carried out on artificially contaminated sand with specific activity of 4.5 10{sup 5} Bk/kg and really contaminated soil from Russian Scientific Center 'Kurchatovsky Institute' (RSC'KI') with specific activity of 2.9 10{sup 4} Bk/kg. It was established that application of ultrasonic intensify the process of soil reagent decontamination and increase its efficiency. The decontamination factor for the artificially contaminated soil was ∼200 and for soil from RSC'KI' ∼30. The flow-sheet diagram has been developed for the new installation as well as determined the main technological characteristics of the equipment. (authors)

Soil science basis and the effect of oil contamination on chemical properties of soils

International Nuclear Information System (INIS)

Wagner, A.; Miehlich, G.

1993-01-01

The changes in soil chemistry properties due to oil contamination and decontamination are examined. One main point of the work is the determination of the effect of oil on the availability of nutrients in the soil. Nutrients are not only present dissolved in the soil solution, but are for the most part reversibly adsorbed by exchangers on loaded surfaces. The clay minerals, the organic substance and iron and manganese oxide act as exchangers. Knowledge on surface structure and reactions in soils contaminated by oil is to be obtained via examination of the exchange behaviour of different bio-elements. The results supply the basis for the cleaning up technique, the judgement of cleaned materials and their reusability. (orig.) [de

Thermal treatment of petroleum contaminated soils - A case study

International Nuclear Information System (INIS)

Bubier, T.W.; Bilello. C.M.

1993-01-01

Thermal treatment is a cost-effective treatment method for removing chemicals from contaminated soils. However, detailed applicability studies are lacking. The goals of this paper are to (1) present the results of a thermal treatment study and (2) discuss the specific elements which must be evaluated prior to determining whether thermal treatment is a feasible option for a remediation project. Results of data collected during a pilot study involving thermal treatment of petroleum contaminated soils at a Marine Terminal are presented. The pilot study consisted of thermally treating the C8 through C40 + (gasoline, kerosene, diesel, motor oil, bunker fuel, etc.) hydrocarbon contaminated soils at treatment temperatures ranging from 250 degrees Fahrenheit (degree F) up to 550 degrees F. The low-temperature thermal treatment unit consisted of a rotary kiln with a temperature capacity of approximately 600 degrees F, a baghouse, and a catalytic oxidizer. The soil was monitored for concentrations of petroleum hydrocarbons and volatile organic compounds before and after treatment. The results of the pilot study were used to determine if thermal treatment technology is a cost-efficient and effective option of remediating the estimated 300,000 tons of petroleum contaminated soil to acceptable cleanup levels. The low-temperature thermal treatment pilot study was effective in desorbing the short chain hydrocarbons (gasoline and diesel) but was not effective in desorbing the long-chain petroleum hydrocarbons, such as motor oils and bunker fuels, from the soil. This was primarily due to the boiling points of motor oil and bunker fuels which were higher than the temperature capacity of the pilot study treatment equipment. Additional factors that influenced the effectiveness of the desorption process included configuration of the treatment equipment, soil moisture content, soil particle size, and type and concentration of petroleum hydrocarbons

Use of soft data in a GIS to improve estimation of the volume of contaminated soil

International Nuclear Information System (INIS)

Hendriks, L.A.M.; Leummens, H.; Stein, A.; Bruijn, P.J. de

1998-01-01

In the practice of soil remediation, organoleptic observations such as the smell or the colour of contaminated soil play an important role when determining well-defined volumes of contaminated soil. A geographical information system (GIS) is then used to combine quantitative measurements with such soft data. In this study general procedures concerning how to deal with this type of observation are presented. The procedures were applied to a former gas works site, which was contaminated with cyanide and polycyclic aromatic hydrocarbons in the Netherlands. The volume of contaminated soil was determined. Use of soft data reduced the uncertainty in the volume of contaminated soil 4 to 16%. 16 refs., 4 figs., 5 tabs

Use of soft data in a GIS to improve estimation of the volume of contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Hendriks, L.A.M.; Leummens, H.; Stein, A.; Bruijn, P.J. de [Agricultural University, Wageningen (Netherlands). Dept. of Soil Science and Geology

1998-01-01

In the practice of soil remediation, organoleptic observations such as the smell or the colour of contaminated soil play an important role when determining well-defined volumes of contaminated soil. A geographical information system (GIS) is then used to combine quantitative measurements with such soft data. In this study general procedures concerning how to deal with this type of observation are presented. The procedures were applied to a former gas works site, which was contaminated with cyanide and polycyclic aromatic hydrocarbons in the Netherlands. The volume of contaminated soil was determined. Use of soft data reduced the uncertainty in the volume of contaminated soil 4 to 16%. 16 refs., 4 figs., 5 tabs.

Soil contamination of toxic metals from zinc carbon batteries inadequate disposal

International Nuclear Information System (INIS)

Gazano, Vanessa Santos Oliveira

2006-01-01

The aim of the present study was to determine the concentration of Zn, Mn, Pb, Cd, Cu, Cr, and Ni in an oxisol column contaminated with zinc-carbon batteries. Two control and two contaminated columns, and batteries alone were leached for a periods of six months and one year with aqueous solution of HNO3 and H2SO4 (1:1, pH 4,0) to simulate rainwater. The metal concentrations in effluent and soil were measured by means of ICP-OES technique. Results from the contaminated column showed enhanced concentrations in both effluent and soil (mainly zinc, manganese and lead). In addition, the total amount of metals in effluent and soil showed similar sequence order as observed for batteries alone (Zn > Mn > Pb > Cr > Cu > Ni > Cd) indicating that batteries can be considered the main source of contamination. We also observed migration of Zn and Mn from the top to the lower layers of the soil columns. The study gives further evidence that batteries can significantly contaminate the soil with metals like Zn, Mn and Pb, and maybe Cd too. This soil contamination combined with the enhanced concentrations found in the effluent can point out a probable groundwater contamination. (author)

Isotopic ratio method for determining uranium contamination

International Nuclear Information System (INIS)

Miles, R.E.; Sieben, A.K.

1994-01-01

The presence of high concentrations of uranium in the subsurface can be attributed either to contamination from uranium processing activities or to naturally occurring uranium. A mathematical method has been employed to evaluate the isotope ratios from subsurface soils at the Rocky Flats Nuclear Weapons Plant (RFP) and demonstrates conclusively that the soil contains uranium from a natural source and has not been contaminated with enriched uranium resulting from RFP releases. This paper describes the method used in this determination which has widespread application in site characterizations and can be adapted to other radioisotopes used in manufacturing industries. The determination of radioisotope source can lead to a reduction of the remediation effort

Applying no-depletion equilibrium sampling and full-depletion bioaccessibility extraction to 35 historically polycyclic aromatic hydrocarbon contaminated soils

DEFF Research Database (Denmark)

Bartolomé, Nora; Hilber, Isabel; Sosa, Dayana

2018-01-01

Assessing the bioaccessibility of organic pollutants in contaminated soils is considered a complement to measurements of total concentrations in risk assessment and legislation. Consequently, methods for its quantification require validation with historically contaminated soils. In this study, 35...... with polyoxymethylene was used to determine freely dissolved concentrations (Cfree) of polycyclic aromatic hydrocarbons (PAHs), while sorptive bioaccessibility extraction (SBE) with silicone rods was used to determine the bioaccessible PAH concentrations (Cbioacc) of these soils. The organic carbon partition...... Capacity Ratio (SCR); particularly for soils with very high KD. The source of contamination determined bioaccessible fractions (fbioacc). The smallest fbioacc were obtained with skeet soils (15%), followed by the pyrogenically influenced soils, rural soils, and finally, the petrogenically contaminated soil...

Nondestructive analysis of plutonium contaminated soil

International Nuclear Information System (INIS)

Smith, H.E.; Taylor, L.H.

1977-01-01

Plutonium contaminated soil is currently being removed from a covered liquid waste disposal trench near the Pu Processing facility on the Hanford Project. This soil with the plutonium is being mined using remote techniques and equipment. The mined soil is being packaged for placement into retrievable storage, pending possible recovery. To meet the requirements of criticality safety and materials accountability, a nondestructive analysis program has been developed to determine the quantity of plutonium in each packing-storage container. This paper describes the total measurement program: equipment systems, calibration techniques, matrix assumption, instrument control program and a review of laboratory operating experience

Bench Scale Treatability Studies of Contaminated Soil Using Soil Washing Technique

OpenAIRE

Gupta, M. K.; Srivastava, R. K.; Singh, A. K.

2010-01-01

Soil contamination is one of the most widespread and serious environmental problems confronting both the industrialized as well as developing nations like India. Different contaminants have different physicochemical properties, which influence the geochemical reactions induced in the soils and may bring about changes in their engineering and environmental behaviour. Several technologies exist for the remediation of contaminated soil and water. In the present study soil washing technique using...

Effect of soil texture on phytoremediation of arsenic-contaminated soils

Science.gov (United States)

Pallud, C. E.; Matzen, S. L.; Olson, A.

2015-12-01

Soil arsenic (As) contamination is a global problem, resulting in part from anthropogenic activities, including the use of arsenical pesticides and treated wood, mining, and irrigated agriculture. Phytoextraction using the hyperaccumulating fern Pteris vittata is a promising new technology to remediate soils with shallow arsenic contamination with minimal site disturbance. However, many challenges still lie ahead for a global application of phytoremediation. For example, remediation times using P. vittata are on the order of decades. In addition, most research on As phytoextraction with P. vittata has examined As removal from sandy soils, where As is more available, with little research focusing on As removal from clayey soils, where As is less available. The objective of this study is to determine the effects of soil texture and soil fertilization on As extraction by P. vittata, to optimize remediation efficiency and decrease remediation time under complex field conditions. A field study was established 2.5 years ago in an abandoned railroad grade contaminated with As (average 85.5 mg kg-1) with texture varying from sandy loam to silty clay loam. Organic N, inorganic N, organic P, inorganic P, and compost were applied to separate sub-plots; control ferns were grown in untreated soil. In a parallel greenhouse experiment, ferns were grown in sandy loam soil extracted from the field (180 mg As kg-1), with similar treatments as those used at the field site, plus a high phosphate treatment and treatments with arbuscular mycorrhizal fungi. In the field study, fern mortality was 24% higher in clayey soil than in sandy soil due to waterlogging, while As was primarily associated with sandy soil. Results from the sandy loam soil indicate that soil treatments did not significantly increase As phytoextraction, which was lower in phosphate-treated ferns than in control ferns, both in the field and greenhouse study. Under greenhouse conditions, ferns treated with organic N were

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.

The organic contamination level based on the total soil mass is not a proper index of the soil contamination intensity

Science.gov (United States)

Hung, H.-W.; Daniel, Sheng G.; Lin, T.-F.; Su, Y.; Chiou, C.T.

2009-01-01

Concentrations of organic contaminants in common productive soils based on the total soil mass give a misleading account of actual contamination effects. This is attributed to the fact that productive soils are essentially water-saturated, with the result that the soil uptake of organic compounds occurs principally by partition into the soil organic matter (SOM). This report illustrates that the soil contamination intensity of a compound is governed by the concentration in the SOM (Com) rather than by the concentration in whole soil (Cs). Supporting data consist of the measured levels and toxicities of many pesticides in soils of widely differing SOM contents and the related levels in in-situ crops that defy explanation by the Cs values. This SOM-based index is timely needed for evaluating the contamination effects of food crops grown in different soils and for establishing a dependable priority ranking for intended remediation of numerous contamination sites.

Soil pollution in the railway junction Niš (Serbia) and possibility of bioremediation of hydrocarbon-contaminated soil

Science.gov (United States)

Jovanovic, Larisa; Aleksic, Gorica; Radosavljevic, Milan; Onjia, Antonije

2015-04-01

Mineral oil leaking from vehicles or released during accidents is an important source of soil and ground water pollution. In the railway junction Niš (Serbia) total 90 soil samples polluted with mineral oil derivatives were investigated. Field work at the railway Niš sites included the opening of soil profiles and soil sampling. The aim of this work is the determination of petroleum hydrocarbons concentration in the soil samples and the investigation of the bioremediation technique for treatment heavily contaminated soil. For determination of petroleum hydrocarbons in the soil samples method of gas-chromatography was carried out. On the basis of measured concentrations of petroleum hydrocarbons in the soil it can be concluded that: Obtained concentrations of petroleum hydrocarbons in 60% of soil samples exceed the permissible values (5000 mg/kg). The heavily contaminated soils, according the Regulation on the program of systematic monitoring of soil quality indicators for assessing the risk of soil degradation and methodology for development of remediation programs, Annex 3 (Official Gazette of RS, No.88 / 2010), must be treated using some of remediation technologies. Between many types of phytoremediation of soil contaminated with mineral oils and their derivatives, the most suitable are phytovolatalisation and phytostimulation. During phytovolatalisation plants (poplar, willow, aspen, sorgum, and rye) absorb organic pollutants through the root, and then transported them to the leaves where the reduced pollutants are released into the atmosphere. In the case of phytostimulation plants (mulberry, apple, rye, Bermuda) secrete from the roots enzymes that stimulates the growth of bacteria in the soil. The increase in microbial activity in soil promotes the degradation of pollutants. Bioremediation is performed by composting the contaminated soil with addition of composting materials (straw, manure, sawdust, and shavings), moisture components, oligotrophs and

Uranium Leaching from Contaminated Soil Utilizing Rhamnolipid, EDTA, and Citric Acid

Directory of Open Access Journals (Sweden)

Sara Asselin

2014-01-01

Full Text Available Biosurfactants have recently gained attention as “green” agents that can be used to enhance the remediation of heavy metals and some organic matter in contaminated soils. The overall objective of this paper was to investigate rhamnolipid, a microbial produced biosurfactant, and its ability to leach uranium present in contaminated soil from an abandoned mine site. Soil samples were collected from two locations in northern Arizona: Cameron (site of open pit mining and Leupp (control—no mining. The approach taken was to first determine the total uranium content in each soil using a hydrofluoric acid digestion, then comparing the amount of metal removed by rhamnolipid to other chelating agents EDTA and citric acid, and finally determining the amount of soluble metal in the soil matrix using a sequential extraction. Results suggested a complex system for metal removal from soil utilizing rhamnolipid. It was determined that rhamnolipid at a concentration of 150 μM was as effective as EDTA but not as effective as citric acid for the removal of soluble uranium. However, the rhamnolipid was only slightly better at removing uranium from the mining soil compared to a purified water control. Overall, this study demonstrated that rhamnolipid ability to remove uranium from contaminated soil is comparable to EDTA and to a lesser extent citric acid, but, for the soils investigated, it is not significantly better than a simple water wash.

Test plan for the soils facility demonstration: A petroleum contaminated soil bioremediation facility

International Nuclear Information System (INIS)

Lombard, K.H.

1994-01-01

The objectives of this test plan are to show the value added by using bioremediation as an effective and environmentally sound method to remediate petroleum contaminated soils (PCS) by: demonstrating bioremediation as a permanent method for remediating soils contaminated with petroleum products; establishing the best operating conditions for maximizing bioremediation and minimizing volatilization for SRS PCS during different seasons; determining the minimum set of analyses and sampling frequency to allow efficient and cost-effective operation; determining best use of existing site equipment and personnel to optimize facility operations and conserve SRS resources; and as an ancillary objective, demonstrating and optimizing new and innovative analytical techniques that will lower cost, decrease time, and decrease secondary waste streams for required PCS assays

Treatment of chromium contaminated soil using bioremediation

Science.gov (United States)

Purwanti, Ipung Fitri; Putri, Tesya Paramita; Kurniawan, Setyo Budi

2017-11-01

Chromium contamination in soil occurs due to the disposal of chromium industrial wastewater or sludge that excess the quality standard. Chromium concentration in soil is ranged between 1 to 300 mg/kg while the maximum health standard is 2.5 mg/kg. Bioremediation is one of technology that could be used for remediating heavy metal contamination in soil. Bacteria have an ability to remove heavy metal from soil. One bacteria species that capable to remove chromium from soil is Bacillus subtilis. The aim of this research was to know the chromium removal percentage in contaminated soil by Bacillus subtilis. Artificial chromium contaminated soil was used by mixing 425gram sand and chromium trichloride solution. Concentration of chromium added into the spiked soil were 50, 75, and 100 mg/L. During 14 days, pH, soil temperature and soil moisture were tested. Initial and final number of bacterial colony and chromium concentration analysed. The result showed that the highest percentage of chromium removal was 11% at a chromium concentration of 75 mg/L

Bioaccumulation of 137Cs by microorganisms isolated from soils contaminated with radionuclides

International Nuclear Information System (INIS)

Pipiska, M.; Hornik, M.; Augustin, J.

2003-01-01

With the aim to evaluate the possibility of utilisation of autochtone population of soil organisms, alone or with participation of higher plants, in the processes of bioremediation the authors quantitatively determined a number of psychrophyllic and mezophyllic germs in the soils contaminated by low-level activities of Cs-137 (0.08 - 2.8 kBq/g). Hereafter they gained isolates of clean cultures of mushrooms and actinomycetes and they determined their bioacumulative activity of Cs-137 at growing conditions. The authors found out, that a number of reproductionable psychrophyllic and mezophyllic germs are significantly lower in the soils with the highest contamination by radionuclides than in the soils with low contamination. They gained the clean cultures of 5 isolates of micromycetes and 3 isolates of actinomycetes from contaminated soil. The micromycetes demonstrated the highest values of bioaccumulation of caesium 39 nmol/g of wet biomass at the growing conditions. In actionoomycetes these values were 4.7 nmol/g (approximately in one order lower). The significant part of cesium accumulated by cell matter at growing conditions were localised in cell matter and it could not be removed by washing with 0.9 percent of NaCl solution. The determined values of bioconcentration factor BCF recalculated on dry weight of biomass were in the range from 16.04 to 26.20 in micromycetes and 3.24 in actinomycetes. From this situation arise, that autochtone population of soil micromycetes and actionomycetes, which is found in contaminated soil, can relevantly participate in the processes of binding of biologically accessible forms of Cs-137 after a creation of suitable conditions for grow. (author)

Bioventing of gasoline-contaminated soil under varied laboratory conditions

International Nuclear Information System (INIS)

Hallman, M.; Shewfelt, K.; Lee, H.; Zytner, R.G.

2002-01-01

Bioventing is becoming a popular in situ soil remediation technology for the treatment of hydrocarbon-contaminated soil. Bioventing relies on enhancing the growth of indigenous microorganisms, which can mineralize the contaminant in the presence of sufficient nutrients. Although bioventing is currently being used as a remediation technology, there are some important questions that remain to be answered in order to optimize the process. These questions include the optimum soil moisture content, type and amount of nutrients necessary, and the best means of producing these conditions in the field. To address these questions, two distinct phases of experiments were conducted. The first experimental phase was designed to determine the optimum moisture content, C:N ratio and form of nitrogen supply for this soil. Using approximately 200g of contaminated soil in each of a series of sealed respirometers, microbial degradation of gasoline under bioventing conditions was quantified for C:N ratios of 5, 10 and 20:1, using varying mixtures of NH 4 + - and NO 3 - -N. The results of the studies indicated that the optimum soil moisture content was 15 wt%, with a C:N ratio of 10:1, using a 100% ammonium application. Using the results of the first phase, a second phase of laboratory research was initiated. Five mesoscale reactors have been developed to simulate the bioventing process that takes place in the field. These reactors are filled with approximately 4kg of gasoline-contaminated soil. The initial results are favourable. (author)

Environmental projects. Volume 14: Removal of contaminated soil and debris

Science.gov (United States)

Kushner, Len

1992-01-01

Numerous diverse activities at the Goldstone Deep Space Communications Complex (GDSCC) are carried out in support of six parabolic dish antennas. Some of these activities can result in possible spills or leakages of hazardous materials and wastes stored both above ground in steel drums and below ground in underground storage tanks (UST's). These possible leaks or spills, along with the past practice of burial of solid debris and waste in trenches and pits, could cause local subsurface contamination of the soil. In 1987, the Jet Propulsion Laboratory (JPL), retained Engineering-Science, Inc. (E-S), Pasadena, California, to identify the specific local areas within the GDSCC with subsurface soil contamination. The E-S study determined that some of the soils at the Apollo Site and the Mars Site were contaminated with hydrocarbons, while soil at a nonhazardous waste dumpsite at the Mojave Base site was contaminated with copper. This volume is a JPL-expanded version of the PE209 E-S report, and it also reports that all subsurface contaminated soils at the GDSCC were excavated, removed, and disposed of in an environmentally acceptable way, and the excavations were backfilled and covered in accordance with accepted Federal, State, and local environmental rules and regulations.

Aided Phytostabilization of Copper Contaminated Soils with L. Perenne and Mineral Sorbents as Soil Amendments

Science.gov (United States)

Radziemska, Maja

2017-09-01

The present study was designed to assess phytostabilization strategies for the treatment of soil co-contaminated by increasing levels of copper with the application mineral amendments (chalcedonite, zeolite, dolomite). From the results it will be possible to further elucidate the benefits or potential risks derived from the application of different types of mineral amendments in the remediation of a copper contaminated soil. A glasshouse pot experiment was designed to evaluate the potential use of different amendments as immobilizing agents in the aided phytostabilization of Cu-contaminated soil using ryegrass (Lolium perenne L.). The content of trace elements in plants and total in soil, were determined using the method of spectrophotometry. All of the investigated element contents in the tested parts of L. perenne were significantly different in the case of applying mineral amendments to the soil, as well as increasing concentrations of copper. The greatest average above-ground biomass was observed for soil amended with chalcedonite. In this experiment, all analyzed metals accumulated predominantly in the roots of the tested plant. In general, applying mineral amendments to soil contributed to decreased levels of copper concentrations.

Hydrogen peroxide treatment of TCE contaminated soil

International Nuclear Information System (INIS)

Hurst, D.H.; Robinson, K.G.; Siegrist, R.L.

1993-01-01

Solvent contaminated soils are ubiquitous in the industrial world and represent a significant environmental hazard due to their persistence and potentially negative impacts on human health and the environment. Environmental regulations favor treatment of soils with options which reduce the volume and toxicity of contaminants in place. One such treatment option is the in-situ application of hydrogen peroxide to soils contaminated with chlorinated solvents such as trichloroethylene (TCE). This study investigated hydrogen peroxide mass loading rates on removal of TCE from soils of varying organic matter content. Batch experiments conducted on contaminated loam samples using GC headspace analysis showed up to 80% TCE removal upon peroxide treatment. Column experiments conducted on sandy loam soils with high organic matter content showed only 25% TCE removal, even at hydrogen peroxide additions of 25 g peroxide per kg soil

DNA adduct quantification in Eisenia fetida after subchronic exposures to creosote contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Charrois, J.W.A.; McGill, W.B. [Alberta Univ., Dept. of Renewable Resources, Edmonton, AB (Canada)

1999-07-01

Within soil ecosystems contaminant toxicity can vary from acute and chronic, depending on the time of exposure. Due to the long times involved chronic toxicity is difficult to determine. DNA adducts fall into the category of biochemical markers that act as an early warning system in environmental monitoring. It has been proposed that they could be used as a sensitive method to determine environmental exposures to compounds such as polycyclic aromatic hydrocarbons (PAHs), which can occur, although not exclusively, in creosote. In this connection, Benzo[a]pyrene (BaP) is a PAH that can be transformed into an electrophilic metabolite, which ultimately results in DNA adduct formation. Use was made of a 32P postlabeling method to quantify the number of DNA adducts occurring in the earthworm Eisenia fetida after exposure to weathered creosote contaminated- and biotreated-soils with and without additions of extra BaP. DNA adducts can be measured in earthworms exposed to creosote contaminated- and biotreated-soils. E. fetida exposed to weathered creosote contaminated soils had significantly more DNA adducts than those exposed to a pristine control soil. Exposures to creosote contaminated soils with additional BaP (1000 mg/kg) or biotreatment did not yield statistically significant increases in DNA adducts compared to the pristine control. (Abstract only)

Developing an integration tool for soil contamination assessment

Science.gov (United States)

Anaya-Romero, Maria; Zingg, Felix; Pérez-Álvarez, José Miguel; Madejón, Paula; Kotb Abd-Elmabod, Sameh

2015-04-01

In the last decades, huge soil areas have been negatively influenced or altered in multiples forms. Soils and, consequently, underground water, have been contaminated by accumulation of contaminants from agricultural activities (fertilizers and pesticides) industrial activities (harmful material dumping, sludge, flying ashes) and urban activities (hydrocarbon, metals from vehicle traffic, urban waste dumping). In the framework of the RECARE project, local partners across Europe are focusing on a wide range of soil threats, as soil contamination, and aiming to develop effective prevention, remediation and restoration measures by designing and applying targeted land management strategies (van Lynden et al., 2013). In this context, the Guadiamar Green Corridor (Southern Spain) was used as a case study, aiming to obtain soil data and new information in order to assess soil contamination. The main threat in the Guadiamar valley 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. Main trace elements contaminating soil and water were As, Cd, Cu, Pb, Tl and Zn. The objective of the present research is to develop informatics tools that integrate soil database, models and interactive platforms for soil contamination assessment. Preliminary results were obtained related to the compilation of harmonized databases including geographical, hydro-meteorological, soil and socio-economic variables based on spatial analysis and stakeholder's consultation. Further research will be modellization and upscaling at the European level, in order to obtain a scientifically-technical predictive tool for the assessment of soil contamination.

Speciation of zinc in contaminated soils

International Nuclear Information System (INIS)

Stephan, Chadi H.; Courchesne, Francois; Hendershot, William H.; McGrath, Steve P.; Chaudri, Amar M.; Sappin-Didier, Valerie; Sauve, Sebastien

2008-01-01

The chemical speciation of zinc in soil solutions is critical to the understanding of its bioavailability and potential toxic effects. We studied the speciation of Zn in soil solution extracts from 66 contaminated soils representative of a wide range of field conditions in both North America and Europe. Within this dataset, we evaluated the links among the dissolved concentrations of zinc and the speciation of Zn 2+ , soil solution pH, total soil Zn, dissolved organic matter (DOM), soil organic matter (SOM) and the concentrations of different inorganic anions. The solid-liquid partitioning coefficient (K d ) for Zn ranged from 17 to 13,100 L kg -1 soil. The fraction of dissolved Zn bound to DOM varied from 60% to 98% and the soil solution free Zn 2+ varied from 40% to 60% of the labile Zn. Multiple regression equations to predict free Zn 2+ , dissolved Zn and the solid-liquid partitioning of Zn are given for potential use in environmental fate modeling and risk assessment. The multiple regressions also highlight some of the most important soil properties controlling the solubility and chemical speciation of zinc in contaminated soils. - We studied the relationships among the chemical speciation of Zn in soil solution extracts from 66 contaminated soils and various physicochemical properties of the soils

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

Bioremediation potential of coal-tar-oil-contaminated soil

International Nuclear Information System (INIS)

Lajoie, C.A.

1991-01-01

The bioremediation of coal tar oil contaminated soil was investigated in 90 day laboratory simulation experiments. The effect of soil moisture, humic acid amendment, and coal tar oil concentration on the rate of disappearance of individual coal tar oil constituents (PAHs and related compounds) was determined by methylene chloride extraction and gas chromatography. Mass balance experiments determined the fate of both the individual 14 C-labeled PAHs phenanthrene, pyrene, and benzo(a)pyrene, and the total coal tar oil carbon. Mineralization, volatilization, incorporation into microbial biomass, disappearance of individual coal tar oil constitutents, and the distribution of residual 14 C-activity in different soil fractions were measured. The rate of disappearance of coal tar oil constituents increased with increasing soil moisture over the experimental range. Humic acid amendment initially enhanced the rate of disappearance, but decreased the extent of disappearance. The amount of contamination removed decreased at higher coal tar oil concentrations. The practical limit for biodegradation in the system tested appeared to be between 1.0 and 2.5% coal tar oil. Mineralization accounted for 40 to 50% of the applied coal tar oil. Volatilization was a minor pathway of disappearance

Vitrification testing of soil fines from contaminated Hanford 100 Area and 300 Area soils

International Nuclear Information System (INIS)

Ludowise, J.D.

1994-01-01

The suitability of Hanford soil for vitrification is well known and has been demonstrated extensively in other work. The tests reported here were carried out to confirm the applicability of vitrification to the soil fines (a subset of the Hanford soil potentially different in composition from the bulk soil) and to provide data on the performance of actual, vitrified soil fines. It was determined that the soil fines were generally similar in composition to the bulk Hanford soil, although the fraction 2 O. The vitrified waste (plus additives) occupies only 60% of the volume of the initial untreated waste. Leach testing has shown the glasses made from the soil fines to be very durable relative to natural and man-made glasses and has demonstrated the ability of the vitrified waste to greatly reduce the release of radionuclides to the environment. Viscosity and electrical conductivity measurements indicate that the soil fines will be readily processable, although with levels of additives slightly greater than used in the radioactive melts. These tests demonstrate the applicability of vitrification to the contaminated soil fines and the exceptional performance of the waste form resulting from the vitrification of contaminated Hanford soils

An Optimised Method to Determine PAHs in a Contaminated Soil; Metodo Optimizado para la Determinacion de PAHs en un Suelo Contaminado

Energy Technology Data Exchange (ETDEWEB)

Garcia Alonso, S.; Perez Pastor, R. M.; Sevillano castano, M. L.; Escolano Segovia, O.; Garcia Frutos, F. J.

2007-07-20

An analytical study is presented based on an optimised method to determine selected polycyclic aromatic hydrocarbons (PAHs) by High Performance Liquid Chromatography (HPLC) with fluorescence detection. The work was focused to obtain reliable measurements of PAH in a gas work contaminated soil and was performed in the frame of the project 'Assessment of natural remediation technologies for PAHs in contaminated soils' (Spanish Plan Nacional l+D+i, CTM 2004-05832-CO2-01): First assays were focused to evaluate an initial proposed procedure by sonication extraction in the contaminated soil. Afterwards to extend the efficiency and reduce solvent and time consuming of extraction procedures, the more relevant parameters that affect the extraction step were investigated. A comparison between sonication and microwave procedures was done, and the influence of sample grinding was studied. In general, both extraction techniques led on comparable results, although sonication procedure needs to be more carefully optimised. Finally, as a final application of the optimised method, the effect of particle size on relative distribution of selected PAHs in the contaminated soil was investigated. Relative abundance of more volatile PAHs showed a decreasing according to lower grain size, while relative abundance of less volatile compounds indicated an increasing of concentration levels for lower grain size. (Author) 10 refs.

The role of soil quality maps in the reuse of lightly contaminated soil

OpenAIRE

Lamé, F.P.J.; Leenaers, H.; Zegwaard, J.

2000-01-01

In 1999 the Dutch government agreed on a new policy regarding the reuse of lightly contaminated soil. From now on, lightly contaminated soil may be reused under conditions of soil-quality management. The municipal authorities supervise the reuse under this new regime. Two basic criteria need to be met before reuse of lightly contaminated soil is allowed. Firstly, the quality of the soil has to be characterised on a soil quality map. Secondly, the soil that will be reused has to be of the same...

Three-dimensional data interpolation for environmental purpose: lead in contaminated soils in southern Brazil.

Science.gov (United States)

Piedade, Tales Campos; Melo, Vander Freitas; Souza, Luiz Cláudio Paula; Dieckow, Jeferson

2014-09-01

Monitoring of heavy metal contamination plume in soils can be helpful in establishing strategies to minimize its hazardous impacts to the environment. The objective of this study was to apply a new approach of visualization, based on tridimensional (3D) images, of pseudo-total (extracted with concentrated acids) and exchangeable (extracted with 0.5 mol L(-1) Ca(NO3)2) lead (Pb) concentrations in soils of a mining and metallurgy area to determine the spatial distribution of this pollutant and to estimate the most contaminated soil volumes. Tridimensional images were obtained after interpolation of Pb concentrations of 171 soil samples (57 points × 3 depths) with regularized spline with tension in a 3D function version. The tridimensional visualization showed great potential of use in environmental studies and allowed to determine the spatial 3D distribution of Pb contamination plume in the area and to establish relationships with soil characteristics, landscape, and pollution sources. The most contaminated soil volumes (10,001 to 52,000 mg Pb kg(-1)) occurred near the metallurgy factory. The main contamination sources were attributed to atmospheric emissions of particulate Pb through chimneys. The large soil volume estimated to be removed to industrial landfills or co-processing evidenced the difficulties related to this practice as a remediation strategy.

Determination of correlation and scaling factors of radionuclides in the contaminated soils from experimental lysimetric field

International Nuclear Information System (INIS)

Dulanska, S.

2009-04-01

contaminated soils of the experimental lysimeter has been found by the classical least-square method. The pair correlation coefficient R suggests the statistical significance of the y i =b 0 + b 1 a( 241 Am) regression model in which yi is the activity of examined radionuclides 238 Pu and 239 , 240 Pu. The statistical significance of the scaling regression models has been confirmed with the Fisher-Snedecor test and also with high values of pair-correlation coefficients R and D for all contaminated soil samples. Given results confirm theoretical assumptions of a possible correlation between investigated alpha radionuclides ( 238 Pu, 239 , 240 Pu, 241 Am) but do not confirm correlations with strontium ( 90 Sr) in such a complicated matrix like the experimental lysimeter soil. It appears that a combined approach using sufficient amount of experimental data and adequate statistical treatment is necessary for the hypothetic model verification. Based on this, a costly and lengthy radiochemical analysis of one of the investigated alpha radionuclides can be consequently replaced by a statistical factor connecting its content with another alpha radionuclide using a mathematical model. Determination of the activity of a radionuclide in contaminated soil may be determined by indirect methods such as an use of the scaling model, which relate the inferred activity concentration of one radionuclide to another that is measured. 241 Am and 239 , 240 Pu were selected as a suitable key nuclide for the determination of parameter linear scaling model for monitoring of radionuclides in the contaminated lysimer soil. The mechanism 239 , 240 Pu is similar as that of 241 Am and 238 Pu which also have similar chemical and physical properties. The scaling model was calculated with 239 , 240 Pu as the indicator variable for estimated radionuclides 238 Pu, 241 Am or with 241 Am as the indicator variable for estimated radionuclides 2 39 , 240 Pu, 238 Pu. The 239 , 240 Pu fraction is the most prominent

Phytoremediation of soils contaminated with radionuclides

International Nuclear Information System (INIS)

Yamaguchi, Isamu

2004-01-01

Aiming at efficient phytoremediation of soils contaminated with radionuclides, we examined the effect of soil microbes on the uptake ability of plants using the multitracer technique to find that tomato rhizofungi in Fusarium spp. can stimulate the uptake of 85 Sr and 137 Cs by the plants. The synergic effect of a nonpathogenic strain of F. oxysporum on the uptake of radionuclides by plants proved to be enhanced by introducing a phytochelatin synthase gene into the fungus. Since soil contamination by radionuclides is still an unsolved problem in many parts of the world. Studies on phytoremediation of polluted soil environment will be important for developing effective strategies and devising adequate techniques to reduce human risks caused by food contamination of radionuclides. (author)

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

Psychrotolerant bacteria for remediation of oil-contaminated soils in the Arctic

Science.gov (United States)

Svarovskaya, L. I.; Altunina, L. K.

2017-12-01

Samples of oil-contaminated peat soil are collected in the region of the Barents Sea in Arctic Kolguyev Island. A model experiment on biodegradation of polluting hydrocarbons by natural microflora exhibiting psychrophilic properties is carried out at +10°C. The geochemical activity of pure hydrocarbon-oxidizing Acinetobacter, Pseudomonas, Bacillus and Rhodococcus cultures isolated from the soil is studied at a lower temperature. The concentration of soil contamination is determined within the range 18-57 g/kg. The biodegradation of oil by natural microflora is 60% under the conditions of a model experiment.

Biological Treatment of Petroleum in Radiologically Contaminated Soil

Energy Technology Data Exchange (ETDEWEB)

BERRY, CHRISTOPHER

2005-11-14

This chapter describes ex situ bioremediation of the petroleum portion of radiologically co-contaminated soils using microorganisms isolated from a waste site and innovative bioreactor technology. Microorganisms first isolated and screened in the laboratory for bioremediation of petroleum were eventually used to treat soils in a bioreactor. The bioreactor treated soils contaminated with over 20,000 mg/kg total petroleum hydrocarbon and reduced the levels to less than 100 mg/kg in 22 months. After treatment, the soils were permanently disposed as low-level radiological waste. The petroleum and radiologically contaminated soil (PRCS) bioreactor operated using bioventing to control the supply of oxygen (air) to the soil being treated. The system treated 3.67 tons of PCRS amended with weathered compost, ammonium nitrate, fertilizer, and water. In addition, a consortium of microbes (patent pending) isolated at the Savannah River National Laboratory from a petroleum-contaminated site was added to the PRCS system. During operation, degradation of petroleum waste was accounted for through monitoring of carbon dioxide levels in the system effluent. The project demonstrated that co-contaminated soils could be successfully treated through bioventing and bioaugmentation to remove petroleum contamination to levels below 100 mg/kg while protecting workers and the environment from radiological contamination.

Effects of Two Kinds of Biochars on Soil Cu Availability in Contaminated Soil

Directory of Open Access Journals (Sweden)

WANG Xiao-qi

2016-07-01

Full Text Available This paper is aimed to research the impacts of different biochars(0,1%,2%,4%, including maize biochar and phytolacca root biochar, on rape growth and the soil Cu availability in the Cu-contaminated red soil via a series of pot experiments. The results showed that, compared with the control, the addition of two kinds of biochars could increase the biomass of the rape. In low Cu-contaminated red soil, added 4% maize biochar and phytolacca root biochar increased the biomass by 21.2 times and 67.9 times; however, the biomass were increased by 8.6 times and 109.6 times under high Cu-contaminated soil. The addition of phytolacca root biochar could increase the soil pH significantly, which has been increased by 0.4~1.6 units with the addition of phytolacca root biochar in low Cu-contaminated red soil, and it had 0.25~1.35 units more than that with maize biochar; In high Cu-contaminated red soil, with the addition of phytolacca root biochar, soil pH was increased by 0.33~1.52 units, which was 0.3~1.25 units higher than maize biochar. There was a significant effect on reducing the soil Cu availability with the addition of the two biochars. Among them, 4% addition of maize biochar and phytolacca root biochar could reduce soil available Cu content by 21.9% and 45.2% in low Cu-contaminated soil, however, it was decreased by 41.9% and 53.8% in high Cu-contaminated soil. Both of the two biochars were able to reduce the Cu accumulation in rape, where there was a decrease by 21.2% and 67.8% with he addition of 4% maize biochar and phytolacca root biochar under low Cu-contaminated soil, and it was decreased by 19.9% and 66.8% in high Cu-contaminated soil respectively. Both of the biochars could ameliorate the acidity and Cu availability in the red soil, enhance the biomass of the rape and reduce the Cu accumulation in rape, but phytolacca root biochar had more effective influence than maize biochar.

Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type.

Science.gov (United States)

Gomes, Helena I; Dias-Ferreira, Celia; Ottosen, Lisbeth M; Ribeiro, Alexandra B

2015-07-01

Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero valent iron particles in a two-compartment cell is tested and compared to a more conventional combination of electrokinetic remediation and nZVI in a three-compartment cell. In the new two-compartment cell, the soil is suspended and stirred simultaneously with the addition of zero valent iron nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used as windows sealants. Saponin, a natural surfactant, was also tested to increase the PCB desorption from soils and enhance dechlorination. Remediation of Soil 1 (with highest pH, carbonate content, organic matter and PCB concentrations) obtained the maximum 83% and 60% PCB removal with the two-compartment and the three-compartment cell, respectively. The highest removal with Soil 2 were 58% and 45%, in the two-compartment and the three-compartment cell, respectively, in the experiments without direct current. The pH of the soil suspension in the two-compartment treatment appears to be a determining factor for the PCB dechlorination, and this cell allowed a uniform distribution of the nanoparticles in the soil, while there was iron accumulation in the injection reservoir in the three-compartment cell. Copyright © 2015 Elsevier Ltd. All rights reserved.

Soil sampling for environmental contaminants

International Nuclear Information System (INIS)

2004-10-01

The Consultants Meeting on Sampling Strategies, Sampling and Storage of Soil for Environmental Monitoring of Contaminants was organized by the International Atomic Energy Agency to evaluate methods for soil sampling in radionuclide monitoring and heavy metal surveys for identification of punctual contamination (hot particles) in large area surveys and screening experiments. A group of experts was invited by the IAEA to discuss and recommend methods for representative soil sampling for different kinds of environmental issues. The ultimate sinks for all kinds of contaminants dispersed within the natural environment through human activities are sediment and soil. Soil is a particularly difficult matrix for environmental pollution studies as it is generally composed of a multitude of geological and biological materials resulting from weathering and degradation, including particles of different sizes with varying surface and chemical properties. There are so many different soil types categorized according to their content of biological matter, from sandy soils to loam and peat soils, which make analytical characterization even more complicated. Soil sampling for environmental monitoring of pollutants, therefore, is still a matter of debate in the community of soil, environmental and analytical sciences. The scope of the consultants meeting included evaluating existing techniques with regard to their practicability, reliability and applicability to different purposes, developing strategies of representative soil sampling for cases not yet considered by current techniques and recommending validated techniques applicable to laboratories in developing Member States. This TECDOC includes a critical survey of existing approaches and their feasibility to be applied in developing countries. The report is valuable for radioanalytical laboratories in Member States. It would assist them in quality control and accreditation process

Organic contaminants in soil : desorption kinetics and microbial degradation

NARCIS (Netherlands)

Schlebaum, W.

1999-01-01

The availability of organic contaminants in soils or sediments for microbial degradation or removal by physical means (e.g.) soil washing or soil venting) depends on the desorption kinetics of these contaminants from the soil matrix. When the organic contaminants desorb very slow from the

Distribution and Source Identification of Pb Contamination in industrial soil

Science.gov (United States)

Ko, M. S.

2017-12-01

INTRODUCTION Lead (Pb) is toxic element that induce neurotoxic effect to human, because competition of Pb and Ca in nerve system. Lead is classified as a chalophile element and galena (PbS) is the major mineral. Although the Pb is not an abundant element in nature, various anthropogenic source has been enhanced Pb enrichment in the environment after the Industrial Revolution. The representative anthropogenic sources are batteries, paint, mining, smelting, and combustion of fossil fuel. Isotope analysis widely used to identify the Pb contamination source. The Pb has four stable isotopes that are 208Pb, 207Pb, 206Pb, and 204Pb in natural. The Pb is stable isotope and the ratios maintain during physical and chemical fractionation. Therefore, variations of Pb isotope abundance and relative ratios could imply the certain Pb contamination source. In this study, distributions and isotope ratios of Pb in industrial soil were used to identify the Pb contamination source and dispersion pathways. MATERIALS AND METHODS Soil samples were collected at depth 0­-6 m from an industrial area in Korea. The collected soil samples were dried and sieved under 2 mm. Soil pH, aqua-regia digestion and TCLP carried out using sieved soil sample. The isotope analysis was carried out to determine the abundance of Pb isotope. RESULTS AND DISCUSSION The study area was developed land for promotion of industrial facilities. The study area was forest in 1980, and the satellite image show the alterations of land use with time. The variations of land use imply the possibilities of bringing in external contaminated soil. The Pb concentrations in core samples revealed higher in lower soil compare with top soil. Especially, 4 m soil sample show highest Pb concentrations that are approximately 1500 mg/kg. This result indicated that certain Pb source existed at 4 m depth. CONCLUSIONS This study investigated the distribution and source identification of Pb in industrial soil. The land use and Pb

Surfactant screening of diesel-contaminated soil

International Nuclear Information System (INIS)

Peters, R.W.; Shem, L.; Montemagno, C.D.; Lewis, B.

1991-01-01

At one installation, approximately 60,000 gal of No. 2 diesel fuel leaked into the subsurface environment, with contamination at depths of 6 to 34 m below the surface. Argonne National Laboratory was contracted to perform treatability studies for site remediation. The treatability studies focused on four separate phases: (1) leachability studies on the various contaminated soil borings, (2) air stripping studies, (3) bioremediation studies, and (4) surfactant screening/surfactant flooding studies. This paper summarizes the fourth phase of the research program in which 21 surfactants were screened for possible use to mobilize the organics from the contaminated soil prior to bioremediation. Anionic surfactants resulted in the greatest degree of diesel mobilization. The most promising surfactants will be employed on actual contaminated soil samples obtained from the site

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.)

Radioactive elements and earthworms in contaminated soils

International Nuclear Information System (INIS)

Suleymanova, A.S.; Abdullayev, A.S.; Ahmadov, G.S.; Naghiyev, J.A.; Samadov, P.A.

2010-11-01

Earthworms are one of the indispensable soil animals which treat soil with letting it through their gut and help increasing soil fertility. The effect of radioactive elements and comparative effect of heavy metals to the vital functions of earthworms were determined in laboratory conditions. Experiments were continued for a month, and first of all, each soil type, grey-brown soil from Ramana iodine plant territory of Baku city, brown soil from Aluminum plant territory of Ganja city, aborigine grey-brown soil of Absheron peninsula, treated with Ra and U salts as model variants and brown soil of Ganja city was analyzed by gamma-spectrometer for radionuclide determining at the beginning and at the end of the experiment. Earthworms (Nicodrilus Caliginosus Sav.trapezoides) aboriginal for Absheron peninsula and plant residues were added to the soil. At the end of the month the biomass, survival value, coprolite allocation value, food activity and catalase value in earthworms and in soil were determined. The gamma-spectrometric analysis results gave interesting values in coprolites, soils which had been treated through the earthworms' gut. In comparison with the initial variants in experimental results more percent of radioactivity was gathered in coprolites. By this way earthworms absorbed most of radioactive elements and allocated them as coprogenous substances on the upper layer of soil. During absorbing, some percents of radioactive elements were also gathered in gut cells of the earthworms. Thereby determination of some vital functions of earthworms was expedient. Thus, by the instrumentality of these experiments we can use earthworms for biodiagnosis and for bioremediation of contaminated soils with radionuclides and heavy metals.

Chelant extraction of heavy metals from contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Peters, R.W. [Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

1999-04-23

The current state of the art regarding the use of chelating agents to extract heavy metal contaminants has been addressed. Results are presented for treatability studies conducted as worst-case and representative soils from Aberdeen Proving Ground's J-Field for extraction of copper (Cu), lead (Pb), and zinc (Zn). The particle size distribution characteristics of the soils determined from hydrometer tests are approximately 60% sand, 30% silt, and 10% clay. Sequential extractions were performed on the 'as-received' soils (worst case and representative) to determine the speciation of the metal forms. The technique speciates the heavy metal distribution into an easily extractable (exchangeable) form, carbonates, reducible oxides, organically-bound, and residual forms. The results indicated that most of the metals are in forms that are amenable to soil washing (i.e. exchangeable+carbonate+reducible oxides). The metals Cu, Pb, Zn, and Cr have greater than 70% of their distribution in forms amenable to soil washing techniques, while Cd, Mn, and Fe are somewhat less amenable to soil washing using chelant extraction. However, the concentrations of Cd and Mn are low in the contaminated soil. From the batch chelant extraction studies, ethylenediaminetetraacetic acid (EDTA), citric acid, and nitrilotriacetic acid (NTA) were all effective in removing copper, lead, and zinc from the J-Field soils. Due to NTA being a Class II carcinogen, it is not recommended for use in remediating contaminated soils. EDTA and citric acid appear to offer the greatest potential as chelating agents to use in soil washing the Aberdeen Proving Ground soils. The other chelating agents studied (gluconate, oxalate, Citranox, ammonium acetate, and phosphoric acid, along with pH-adjusted water) were generally ineffective in mobilizing the heavy metals from the soils. The chelant solution removes the heavy metals (Cd, Cu, Pb, Zn, Fe, Cr, As, and Hg) simultaneously. Using a multiple

Chelant extraction of heavy metals from contaminated soils

International Nuclear Information System (INIS)

Peters, R.W.

1999-01-01

The current state of the art regarding the use of chelating agents to extract heavy metal contaminants has been addressed. Results are presented for treatability studies conducted as worst-case and representative soils from Aberdeen Proving Ground's J-Field for extraction of copper (Cu), lead (Pb), and zinc (Zn). The particle size distribution characteristics of the soils determined from hydrometer tests are approximately 60% sand, 30% silt, and 10% clay. Sequential extractions were performed on the 'as-received' soils (worst case and representative) to determine the speciation of the metal forms. The technique speciates the heavy metal distribution into an easily extractable (exchangeable) form, carbonates, reducible oxides, organically-bound, and residual forms. The results indicated that most of the metals are in forms that are amenable to soil washing (i.e. exchangeable+carbonate+reducible oxides). The metals Cu, Pb, Zn, and Cr have greater than 70% of their distribution in forms amenable to soil washing techniques, while Cd, Mn, and Fe are somewhat less amenable to soil washing using chelant extraction. However, the concentrations of Cd and Mn are low in the contaminated soil. From the batch chelant extraction studies, ethylenediaminetetraacetic acid (EDTA), citric acid, and nitrilotriacetic acid (NTA) were all effective in removing copper, lead, and zinc from the J-Field soils. Due to NTA being a Class II carcinogen, it is not recommended for use in remediating contaminated soils. EDTA and citric acid appear to offer the greatest potential as chelating agents to use in soil washing the Aberdeen Proving Ground soils. The other chelating agents studied (gluconate, oxalate, Citranox, ammonium acetate, and phosphoric acid, along with pH-adjusted water) were generally ineffective in mobilizing the heavy metals from the soils. The chelant solution removes the heavy metals (Cd, Cu, Pb, Zn, Fe, Cr, As, and Hg) simultaneously. Using a multiple-stage batch extraction

Chelant extraction and REDOX manipulation for mobilization of heavy metals from contaminated soils

International Nuclear Information System (INIS)

Brewster, M.D.; Peters, R.W.; Miller, G.A.; Patton, T.L.; Martino, L.E.

1994-01-01

Was the result of open burning and open detonation of chemical agents and munitions in the Toxic Burning Pits area at J-Field, located in the Edgewood Area of Aberdeen Proving Ground in Harford County, Maryland, soils have been contaminated with heavy metals. Simultaneous extraction is complicated because of the multitude of contaminant forms that exist. This paper uses data from a treatability study performed at Argonne National Laboratory to discuss and compare several treatment methods that were evaluated for remediating metals-contaminated soils. J-Field soils were subjected to a series of treatability experiments designed to determine the feasibility of using soil washing/soil flushing, enhancements to soil washing/soil flushing, solidification/stabilization, and electrokinetics for remediating soils contaminated with metals. Chelating and mobilizing agents evaluated included ammonium acetate, ethylenediaminetetraacetic acid, citric acid, Citranox, gluconic acid, phosphoric acid, oxalic acid, and nitrilotriacetic acid, in addition to pH-adjusted water. REDOX manipulation can maximize solubilities, increase desorption, and promote removal of heavy metal contaminants. Reducing agents that were studied included sodium borohydride, sodium metabisulfite, and thiourea dioxide. The oxidants studied included hydrogen peroxide, sodium percarbonate, sodium hypochlorite, and potassium permanganate. This paper summaries the results from the physical/chemical characterization, soil washing/soil flushing, and enhancements to soil washing/soil flushing portions of the study

Biodegradation of dicyclopentadiene by a mini-consortium isolated from hydrocarbon contaminated soil

International Nuclear Information System (INIS)

Shen, Y.; Stehmeier, L.; Voordouw, G.

1997-01-01

Thirty-five bacterial species were isolated from soil contaminated by low molecular weight hydrocarbons (C5+). All species were identified by gene sequencing. The isolated genomic DNAs from these bacteria were spotted on a master filter in denatured form. They were then hybridized with total community DNAs isolated from soil exposed to dicyclopentadiene (DCPD) in order to determine the effect of DCPD on the soil microbial community by comparison with an untreated control group. Incubation of soil with DCPD enriched a Sphingomonas sp. while incubation with DCPD in the absence of soil gave enrichment of a Pseudomonas sp. These results indicate that identification of bacterial isolates with DCPD degrading potential is possible and that such organisms can be isolated from C5+ contaminated sites. However, the possibility of removing DCPD contamination in soil by bioremediation is not yet proven.10 refs., 2 tabs., 2 figs

APPLICATION OF ZEOLITE AND BENTONITE FOR STABILIZING LEAD IN A CONTAMINATED SOIL

Directory of Open Access Journals (Sweden)

Agnieszka Andrzejewska

2017-08-01

The study evaluated the properties of zeolite and bentonite for stabilizing lead (Pb in a contaminated soil. Sorbents were applied at different rates 0, 0.25, 0.5, 1.0, 2.0, and 3.0% to the contaminated soil and incubated for four months. Soil reaction (pH was measured as well as the electrical conductivity (EC. The total content of Pb was determined in the soil samples as did the reactive forms (extracted by 0.11 mol CH3HCOOH dm-3. The evaluation of the efficiency of the stabilization of Pb was performed on the basis of the fractions of the reactive lead. It was found, that the addition of both zeolite and bentonite resulted in a decrease in the concentrations of the active forms of lead in soils. Thus, the two sorbents exerted a good stability and can be used for efficiently immobilizing lead in soil contaminated anthropogenically.

Potential of Trichoderma spp. strains for the bioremediation of soils contaminated with petroleum

Directory of Open Access Journals (Sweden)

Marcia Pesántez

2016-10-01

Full Text Available Fungi species can degrade xenobiotic compounds contaminating the soil, including hydrocarbons. The objective of this work was to determine the potential of three strains of Trichoderma, isolated from soil contaminated with petroleum, for bioremediation. Trichoderma harzianum CCECH-Te1, Trichoderma viride CCECH-Te2 and Trichoderma psedokoningii CCECH-Te3 were included in one assay with each independent strain. The inoculum was adjusted to a concentration of 1x1010 conidia ml-1 which was applied to soil contaminated by an oil spill. After 96 days of inoculation, soil samples were taken at 10 and 15 cm depth. The content of total hydrocarbons, polycyclic aromatic hydrocarbons and heavy metals such as cadmium, nickel and lead were determined. With the data, it was calculated the percentage of removal of the analyzed compounds by each strain. At 10 cm and 15 cm depth, it was observed the removal of the compounds in percentages that reached between 47 and 69.1% in the hydrocarbons and up to 53.72% in the heavy metals. It which denoted the potential of the three strains for bioremediation in contaminated soils.   Keywords: heavy metals, polycyclic aromatic hydrocarbons, xenobiotic compounds

Bioremediation of petroleum-contaminated soil

International Nuclear Information System (INIS)

Pearce, K.; Snyman, H.G.; Oellermann, R.A.; Gerber, A.

1995-01-01

A pilot-scale study was conducted to evaluate the application of land-farming techniques in bioremediating a soil highly contaminated with petroleum products. A commercial biosupplement, and one prepared with indigenous microorganisms from the contaminated soil, were tested. Application of either of the biosupplements, in addition to the control of pH, moisture, and oxygen levels, resulted in a 94% reduction of the initial total petroleum hydrocarbon concentration (TPHC) (32% mass/mass) over a 70-day period. Implementation of these findings at full scale to bioremediate highly weathered petroleum products showed an average reduction of 89% over 5.5 months. Target levels of 1,400 mg/kg soil were reached from an initial average TPHC concentration of 12,200 mg/kg soil

NORM remediation project of Der Ezzor Petroleum Company (DEZPC) oil fields in Der Ezzor area, Syrian Arab Republic: Determination of NORM contaminated soil volumes

International Nuclear Information System (INIS)

Al-Masri, M. S.; Aba, A.; Hamwi, A.; Hassan, M.

2002-04-01

DEZP Company has used to collect product water, scale and sludge in artificial pits. Run-off channel had been created to allow water to run-off into the desert. A radioactive contamination by NORM in DEZP oil fields (JAFRA) has occurred and quite significant area of land has been affected. As a part of the remediation project the volume of contaminated soil with NORM according to the Syrian criteria for clean up and disposal has been determined. Surface and core soil samples were collected from the contaminated areas and analyzed for 226 Ra. The results have shown that contamination has reached a depth of more than one meter in the surface water pit. The estimated contaminated soil that needs disposal according to the Syrian criteria was calculated and found to be about 3161 m 3 . Most of the contaminated soil was found to be in the surface water pit. In addition, the contamination in the mud pit and the run-off channel was rather small and could be treated on site. However, the obtained results can be used for preparation of the remediation plan where size of the disposal pit and on site treatment is defined. The plan should be submitted to the Syrian Regulatory Office for review and approval to initiation of the remediation work (author)

Immobilization of Lead Migrating from Contaminated Soil in Rhizosphere Soil of Barley (Hordeum vulgare L.) and Hairy Vetch (Vicia villosa) Using Hydroxyapatite.

Science.gov (United States)

Katoh, Masahiko; Risky, Elsya; Sato, Takeshi

2017-10-23

This study conducted plant growth tests using a rhizobox system to quantitatively determine the distance of immobilization lead migrating from contaminated soil into uncontaminated rhizosphere soil, and to assess the lead phases accumulated in rhizosphere soil by sequential extraction. Without the hydroxyapatite, exchangeable lead fractions increased as the rhizosphere soil got closer to the contaminated soil. Exchangeable lead fractions were higher even in the rhizosphere soil that shares a boundary with the root surface than in the soil before being planted. Thus, plant growth of hairy vetch was lower in the soil without the hydroxyapatite than in the soil with the hydroxyapatite. The presence of hydroxyapatite may immobilize the majority of lead migrating from contaminated soil into the rhizosphere soil within 1 mm from the contaminated soil. The dominant lead fraction in the rhizosphere soil with the hydroxyapatite was residual. Thus, plant growth was not suppressed and the lead concentration of the plant shoot remained at the background level. These results indicate that the presence of hydroxyapatite in the rhizosphere soil at 5% wt may immobilize most of the lead migrating into the rhizosphere soil within 1 mm from the contaminated soil, resulting in the prevention of lead migration toward the root surface.

Heavy-metal contamination of soils in Saxony/Germany by foundry fumes and low-cost rapid analyses of contaminated soils by XRF

Science.gov (United States)

Mucke, D.

2012-04-01

spectrometry (XRF) with a handheld instrument. Approx. 40 elements hereby are determined in a focussed X-ray spot of 3 mm of diameters. The device can be put directly on a section of the soil or measure loose substrata in a PVC bag through or in a cuvette. The measurement time is 30 seconds. In connection with the input of information, the relocating and the sample preparation 20 measurings can be carried out per hour. This leads at personnel expenditures of € 50/hour at a price of € 2.50/analysis of simultaneous 40 components. At requirement the transfer of the files from the instrument in Excel tables still would rise expenses. XRF is a fast low-cost method for the first assessment of the contamination of soils and the delimitation of areas of different contaminations. When exact laboratory analyses are still requested, the interesting areas from which bulk samples have to be taken for the laboratory examinations, with XRF can be fixed. The contamination with arsenic and toxic heavy metals is only subordinated by modern flue gas treatment in metallurgical plants and renunciation of thermal methods with hut smoke today. The whereabouts of arsenic and lead in the soil shows, though, that the soil has protected the groundwater against the contamination. GEOMONTAN has examined the Saxonian areas with radioactive fallout of the Chernobyl accident in the order of the BGR Hannover 1993. In the results of the analysis by BGR Cs-134 was already disintegrated and Cs-137 only 13 cm deep in the uppermost soil layers infiltrated during the 8 years after the accident. This means that soil protects groundwater against contaminations out of the air too. In the last years some German federal state governments decided the end of mine water winning for the public water supply and deregulated the water protection zones. The water supply was converted in water of water supply dams. The hazard of contamination of this open reservoirs by accidents or terrorism is increasing. Underground water

Cancer risk assessment of polycyclic aromatic hydrocarbon contaminated soils determined using bioassay-derived levels of benzo[a]pyrene equivalents.

Science.gov (United States)

Lemieux, Christine L; Long, Alexandra S; Lambert, Iain B; Lundstedt, Staffan; Tysklind, Mats; White, Paul A

2015-02-03

Here we evaluate the excess lifetime cancer risk (ELCR) posed by 10 PAH-contaminated soils using (i) the currently advocated, targeted chemical-specific approach that assumes dose additivity for carcinogenic PAHs and (ii) a bioassay-based approach that employs the in vitro mutagenic activity of the soil fractions to determine levels of benzo[a]pyrene equivalents and, by extension, ELCR. Mutagenic activity results are presented in our companion paper.1 The results show that ELCR values for the PAH-containing fractions, determined using the chemical-specific approach, are generally (i.e., 8 out of 10) greater than those calculated using the bioassay-based approach; most are less than 5-fold greater. Only two chemical-specific ELCR estimates are less than their corresponding bioassay-derived values; differences are less than 10%. The bioassay-based approach, which permits estimation of ELCR without a priori knowledge of mixture composition, proved to be a useful tool to evaluate the chemical-specific approach. The results suggest that ELCR estimates for complex PAH mixtures determined using a targeted, chemical-specific approach are reasonable, albeit conservative. Calculated risk estimates still depend on contentious PEFs and cancer slope factors. Follow-up in vivo mutagenicity assessments will be required to validate the results and their relevance for human health risk assessment of PAH-contaminated soils.

Development of Decontamination Process for Soil Contaminated Uranium

International Nuclear Information System (INIS)

Kim, Gye-Nam; Kim, Seung-Soo; Park, Uk-Rang; Han, Gyu-Seong; Moon, Jei-Kwon

2014-01-01

Various experiments with full-scaled electrokinetic equipment, soil washing equipment, and gravel washing equipment were performed to remove 238 U from contaminated soils of below 0.4 Bq/g. The repetition number and the removal efficiencies of the soil and gravel washing equipment were evaluated. The decontamination periods by the soil and gravel electrokinetic equipment were evaluated. Finally, a work process of full-scaled decontamination equipment was developed. Contaminated soils were classified into soils and gravels using a 8.0 cm sieve. Soils were sent to the soil washing equipment, while gravels were sent to the gravel washing equipment. Soils sent to the soil washing equipment were sent to the soil electrokinetic equipment after soil washing. A repetition number of soil washing was two times. The washed gravels were sent to the gravel electrokinetic equipment. Gravel contaminated with a high concentration requires crushing after gravel washing

Development of Decontamination Process for Soil Contaminated Uranium

Energy Technology Data Exchange (ETDEWEB)

Kim, Gye-Nam; Kim, Seung-Soo; Park, Uk-Rang; Han, Gyu-Seong; Moon, Jei-Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-10-15

Various experiments with full-scaled electrokinetic equipment, soil washing equipment, and gravel washing equipment were performed to remove {sup 238}U from contaminated soils of below 0.4 Bq/g. The repetition number and the removal efficiencies of the soil and gravel washing equipment were evaluated. The decontamination periods by the soil and gravel electrokinetic equipment were evaluated. Finally, a work process of full-scaled decontamination equipment was developed. Contaminated soils were classified into soils and gravels using a 8.0 cm sieve. Soils were sent to the soil washing equipment, while gravels were sent to the gravel washing equipment. Soils sent to the soil washing equipment were sent to the soil electrokinetic equipment after soil washing. A repetition number of soil washing was two times. The washed gravels were sent to the gravel electrokinetic equipment. Gravel contaminated with a high concentration requires crushing after gravel washing.

Analysis of soils contaminated with petroleum constituents

International Nuclear Information System (INIS)

O'Shay, T.A.; Hoddinott, K.

1994-01-01

This symposium was held in Atlanta, Georgia on June 24, 1993. The purpose of the symposium was to provide a forum for exchange of information on petroleum contaminated soils. When spilled on the ground, petroleum products can cause massive problems in the environment. In this Special Technical Publication (STP), papers were selected in two categories; the analytical procedures for soil contaminated with petroleum hydrocarbons and the behavior of hydrocarbon contaminated soils. Individual papers have been processed separately for inclusion in the appropriate data bases

Can impurities from soil-contaminated coffees reach the cup?

International Nuclear Information System (INIS)

Tagliaferro, F.S.; De Nadai Fernandes, E.A.; Bacchi, M.A.; Joacir De Franca, E.; Bode, P.

2007-01-01

Depending on the harvest conditions, coffee beans can be contaminated by soil when dropped to the ground. It is well known that agricultural soils act as sinks for agrochemicals applied to the crops. While coffee is brewed, substances present in the roasted and ground coffee beans are extracted by hot water, emphasizing the need to assess the possible transfer of impurities from the soil to the beverage. Soil-contaminated samples of roasted coffee beans were split into 2 groups according to the treatments: (a) washed and ground and (b) only ground. Brewing was performed in a household espresso machine for both coffees. The resulting beverage was freeze-dried and the elemental composition determined by instrumental neutron activation analysis (INAA). The mass fractions of the terrigenous elements Fe, La, Sc, Sm and Th in the freeze-dried non-washed coffee beverages were, at least, 2 times higher than in the washed samples. These elements are tracers of the soil, indicating that the impurities from the soil reached the beverage. (author)

Bioremediation potential of diesel-contaminated Libyan soil.

Science.gov (United States)

Koshlaf, Eman; Shahsavari, Esmaeil; Aburto-Medina, Arturo; Taha, Mohamed; Haleyur, Nagalakshmi; Makadia, Tanvi H; Morrison, Paul D; Ball, Andrew S

2016-11-01

Bioremediation is a broadly applied environmentally friendly and economical treatment for the clean-up of sites contaminated by petroleum hydrocarbons. However, the application of this technology to contaminated soil in Libya has not been fully exploited. In this study, the efficacy of different bioremediation processes (necrophytoremediation using pea straw, bioaugmentation and a combination of both treatments) together with natural attenuation were assessed in diesel contaminated Libyan soils. The addition of pea straw was found to be the best bioremediation treatment for cleaning up diesel contaminated Libyan soil after 12 weeks. The greatest TPH degradation, 96.1% (18,239.6mgkg(-1)) and 95% (17,991.14mgkg(-1)) were obtained when the soil was amended with pea straw alone and in combination with a hydrocarbonoclastic consortium respectively. In contrast, natural attenuation resulted in a significantly lower TPH reduction of 76% (14,444.5mgkg(-1)). The presence of pea straw also led to a significant increased recovery of hydrocarbon degraders; 5.7log CFU g(-1) dry soil, compared to 4.4log CFUg(-1) dry soil for the untreated (natural attenuation) soil. DGGE and Illumina 16S metagenomic analyses confirm shifts in bacterial communities compared with original soil after 12 weeks incubation. In addition, metagenomic analysis showed that original soil contained hydrocarbon degraders (e.g. Pseudoxanthomonas spp. and Alcanivorax spp.). However, they require a biostimulant (in this case pea straw) to become active. This study is the first to report successful oil bioremediation with pea straw in Libya. It demonstrates the effectiveness of pea straw in enhancing bioremediation of the diesel-contaminated Libyan soil. Copyright © 2016 Elsevier Inc. All rights reserved.

Investigation of plutonium behaviour in artificially contaminated soil

International Nuclear Information System (INIS)

Lukshiene, B.; Druteikiene, R.

2006-01-01

The vertical migration and transformation of plutonium chemical forms artificially supplied to sandy loam columns after its exposure to natural conditions for about one year was investigated. An analysis of artificially contaminated samples after one year had shown that 81% of 239 Pu 4+ and 44% of 239 Pu 3+ were accumulated in the 0-5 cm layer of sandy loam. The data of sequential analysis of the same type of soil at the adequate artificial contamination level after one month exposure under laboratory conditions are presented as well. Pu 239 binding to soil geochemical fractions was rather uneven. The largest amount of Pu 239 (60 %) was determined in the residual fraction. Consequently, it can be assumed that organic substances and some inorganic compounds, which usually are the main components of a residual fraction, affects the retention and migration of plutonium in the soil. (authors)

Investigation of plutonium behaviour in artificially contaminated soil

International Nuclear Information System (INIS)

Luksiene, B.; Druteikiene, R.

2006-01-01

The vertical migration and transformation of plutonium chemical forms artificially supplied to sandy loam columns after its exposure to natural conditions for about one year was investigated. An analysis of artificially contaminated samples after one year had shown that 81% of 239 Pu 4+ and 44% of 239 Pu 3+ were accumulated in the 0-5 cm layer of sandy loam. The data of sequential analysis of the same type of soil at the adequate artificial contamination level after one month exposure under laboratory conditions are presented as well. Pu 239 binding to soil geochemical fractions was rather uneven. The largest amount of Pu 239 (60%) was determined in the residual fraction. Consequently, it can be assumed that organic substances and some inorganic compounds, which usually are the main components of a residual fraction, affects the retention and migration of plutonium in the soil. (authors)

SOIL WASHING TREATABILITY TESTS FOR PESTICIDE- CONTAMINATED SOIL

Science.gov (United States)

The 1987 Sand Creek Operable Unit 5 record of decision (ROD) identified soil washing as the selected technology to remediate soils contaminated with high levels of organochlorine pesticides, herbicides, and metals. Initial treatability tests conducted to assess the applicability...

Arsenic adsorption of lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil

Directory of Open Access Journals (Sweden)

Wuthiphun, L.

2007-05-01

Full Text Available Arsenic adsorption efficiency of soil covering materials (lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil obtained from Ronpiboon District, Nakhon Sri Thammarat Province tosolve arsenic air pollution problem was investigated using batch experiments. The four types of the aforementioned soil covering materials were examined to determine their arsenic adsorption efficiency, equilibriumtime as well as adsorption isotherms.The results revealed that among soil covering materials mixed with arsenic-contaminated soil at 10% w/w, the efficiency of arsenic adsorption of fly ash, lateritic soil, lime and limestone powder were 84, 60,38 and 1% respectively. The equilibrium time for lateritic soil at pH 4 was achieved within 4 hrs, whereas pH 7 and 12, the equilibrium time was 6 hrs. For fly ash, 2 hrs were required to reach the equilibrium at pH 12, while the equilibrium time was attained within 6 hrs at pH 4 and 7. Furthermore, lateritic soil possessedhigh arsenic adsorption efficiency at pH 7 and 4 and best fit with the Langmuir isotherm. The fly ash showing high arsenic adsorption efficiency at pH 12 and 7 fit the Freundlich isotherm at pH 12 and Langmuirisotherm at pH 7.This indicated that lateritic soil was suitable for arsenic adsorption at low pH, whilst at high pH,arsenic was well adsorbed by fly ash. The Freundlich and Langmuir isotherm could be used to determine quantities of soil covering materials for arsenic adsorption to prevent arsenic air pollution from arseniccontaminated soils.

The time-dependent effect of the biological component of 137Cs soil contamination

International Nuclear Information System (INIS)

Dederichs, H.; Pillath, J.; Lennartz, R.; Hill, P.; Hille, R.

2004-01-01

In investigations of the long-term development of the population dose in the highly contaminated regions of the Commonwealth of Independence States it was found that the external dose has not decreased as strongly as expected since 1992. Further investigations have shown that, contrary to expectations, no linear correlation can be observed between soil contamination and measured area dose rate. As a contribution towards clarifying these issues, the area dose rate and the soil contamination including the plant fraction were investigated in the Korma district, Belarus. It was found that it is necessary to cover and average over larger areas in order to determine from ground contamination the long-term development of the external dose commitment. This means that for this purpose the introduction of an ''effective'' surface contamination (sum of mineral and organic contamination components) is necessary. The phenomena observed are described in a model, which permits an analytical calculation of the contamination profile in soil taking migration and transfer effects into account. The differences observed between the measured soil contamination and the resulting external doses or the directly measured dose rate can be explained by the proposed model. Moreover, their long-term development can be calculated. The results show that a time decade after the accident the biological part of the ''effective'' soil contamination becomes dominant and cannot be neglected. (orig.)

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...

Algal tests with soil suspensions and elutriates: A comparative evaluation for PAH contaminated soils

DEFF Research Database (Denmark)

Baun, Anders; Justesen, Kasper Bo; Nyholm, Niels

2002-01-01

An algal growth inhibition test procedure with soil suspensions is proposed and evaluated for PAH-contaminated soil. The growth rate reduction of the standard freshwater green alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum) was used as the toxicity endpoint......, and was quantified by measuring the fluorescence of solvent-extracted algal pigments. No growth rate reduction was detected for soil contents up to 20 g/l testing five non-contaminated Danish soils. Comparative testing with PAH-contaminated soil elutriates and soil suspensions showed that the suspensions had...

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.

Flotation separation of uranium from contaminated soils

International Nuclear Information System (INIS)

Misra, M.; Mehta, R.; Garcia, H.; Chai, C.D.; Smith, R.W.

1995-01-01

The volume of low-level contaminated soil at the Department of Energy's Nuclear Weapon Sites are in the order of several million tons. Most of the contaminants are uranium, plutonium, other heavy metals and organic compounds. Selected physical separation processes have shown demonstrated potential in concentrating the radionuclides in a small fraction of the soil. Depending upon the size, nature of bonding and distributions of radionuclides, more than 90% of the radionuclide activity can be concentrated in a small volume of fraction of the soil. The physico-chemical separation processes such as flotation in a mechanical and microbubble tall column cell have shown promising applications in cleaning up the high volume contaminated soil

Bioremediation of petroleum-contaminated soil: A Review

Science.gov (United States)

Yuniati, M. D.

2018-02-01

Petroleum is the major source of energy for various industries and daily life. Releasing petroleum into the environment whether accidentally or due to human activities is a main cause of soil pollution. Soil contaminated with petroleum has a serious hazard to human health and causes environmental problems as well. Petroleum pollutants, mainly hydrocarbon, are classified as priority pollutants. The application of microorganisms or microbial processes to remove or degrade contaminants from soil is called bioremediation. This microbiological decontamination is claimed to be an efficient, economic and versatile alternative to physicochemical treatment. This article presents an overview about bioremediation of petroleum-contaminated soil. It also includes an explanation about the types of bioremediation technologies as well as the processes.

assessment of trace metals contamination of soils around some ...

African Journals Online (AJOL)

ABSTRACT. This study was carried out to determine the level of soil contamination by metals around some automobile mechanic .... and this was done all through the sample preparation. ... shaking was done by a mechanical sieve shaker and.

Decontamination of Soils Contaminated with Co and Cs by Using an Acid Leaching Process

International Nuclear Information System (INIS)

Jung-Joon, Lee; Gye-Nam, Kim; Jei-Kwon, Moon; Kune-Woo, Lee

2009-01-01

Acid leaching process has been adapted for the remediation of soils contaminated with heavy metals and radionuclides. This method has been reported to be simple, and economically promising. Moreover it can be applicable for on-site and off-site remediations as well. Investigations were conducted on an acid leaching process using surrogate contaminated soils. Size sieving, agglomeration and column leaching were carried out with soils artificially contaminated with Co and Cs, respectively. Size distribution was analyzed for a determination of the particle size required to be agglomerated. Because of the low water permeability of the soils due to their fine particles, they were sieved by using a sieve with a 0.075 mm size (No. 200 mesh) for an agglomeration. The soils with a size smaller than 0.075 mm were agglomerated by using 2 % sodium silicate (Na 2 SiO 3 ), while the soils with a size larger than 0.075 mm were used directly for the column leaching test. From the preliminary test (the batch scale leaching test), 0.1 M of HCl was determined as the effective leaching agent for Co and Cs. Finally, the soils mixed with the coarse soil and the agglomerated soil were decontaminated with 0.1 M HCl within 11.3 days and the removal efficiencies of Co and Cs were 94.0 % and 82.8 %, respectively. In conclusion, an acid leaching process could be applied for a remediation of soils contaminated with radionuclides such as Co and Cs. (authors)

Bioremediation of uranium contaminated Fernald soils

International Nuclear Information System (INIS)

Delwiche, M.E.; Wey, J.E.; Torma, A.E.

1994-01-01

This study investigated the use of microbial bioleaching for removal of uranium from contaminated soils. The ability of bacteria to assist in oxidation and solubilization of uranium was compared to the ability of fungi to produce complexing compounds which have the same effect. Biosorption of uranium by fungi was also measured. Soil samples were examined for changes in mineralogical properties due to these processes. On the basis of these laboratory scale studies a generalized flow sheet is proposed for bioremediation of contaminated Fernald soils

CO₂ and O₂ respiration kinetics in hydrocarbon contaminated soils amended with organic carbon sources used to determine catabolic diversity.

Science.gov (United States)

Pietravalle, Stéphane; Aspray, Thomas J

2013-05-01

Multiple substrate induced respiration (MSIR) assays which assess the response of soils to carbon source amendment are effective approaches to determine catabolic diversity of soils. Many assays are based on a single short term (hydrocarbon contaminated soils using continuous CO2 and O2 respiration measurements. Based on cumulative CO2 and O2 measurements at 4, 24 and 120 h, the soils were found to be distinct in terms of their catabolic diversity. Most noteworthy, however, was the response to the addition of maleic acid which provided strong evidence of abiotic CO2 efflux to be the overriding process, raising questions about the interpretation of CO2 only responses from organic acid addition in MSIR assays. Copyright © 2013 Elsevier Ltd. All rights reserved.

Controlled release fertilizer increased phytoremediation of petroleum-contaminated sandy soil.

Science.gov (United States)

Cartmill, Andrew D; Cartmill, Donita L; Alarcón, Alejandro

2014-01-01

A greenhouse experiment was conducted to determine the effect of the application of controlled release fertilizer [(CRF) 0, 4,6, or 8 kg m(-3)] on Lolium multiflorum Lam. survival and potential biodegradation of petroleum hydrocarbons (0, 3000, 6000, or 15000 mg kg(-1)) in sandy soil. Plant adaptation, growth, photosynthesis, total chlorophyll, and proline content as well as rhizosphere microbial population (culturable heterotrophic fungal and bacterial populations) and total petroleum hydrocarbon (TPH)-degradation were determined. Petroleum induced-toxicity resulted in reduced plant growth, photosynthesis, and nutrient status. Plant adaptation, growth, photosynthesis, and chlorophyll content were enhanced by the application of CRF in contaminated soil. Proline content showed limited use as a physiological indicator of petroleum induced-stress in plants. Bacterial and filamentous fungi populations were stimulated by the petroleum concentrations. Bacterial populations were stimulated by CRF application. At low petroleum contamination, CRF did not enhance TPH-degradation. However, petroleum degradation in the rhizosphere was enhanced by the application of medium rates of CRF, especially when plants were exposed to intermediate and high petroleum contamination. Application of CRF allowed plants to overcome the growth impairment induced by the presence of petroleum hydrocarbons in soils.

Green waste compost as an amendment during induced phytoextraction of mercury-contaminated soil.

Science.gov (United States)

Smolinska, Beata

2015-03-01

Phytoextraction of mercury-contaminated soils is a new strategy that consists of using the higher plants to make the soil contaminant nontoxic. The main problem that occurs during the process is the low solubility and bioavailability of mercury in soil. Therefore, some soil amendments can be used to increase the efficiency of the Hg phytoextraction process. The aim of the investigation was to use the commercial compost from municipal green wastes to increase the efficiency of phytoextraction of mercury-contaminated soil by Lepidium sativum L. plants and determine the leaching of Hg after compost amendment. The result of the study showed that Hg can be accumulated by L. sativum L. The application of compost increased both the accumulation by whole plant and translocation of Hg to shoots. Compost did not affect the plant biomass and its biometric parameters. Application of compost to the soil decreased the leaching of mercury in both acidic and neutral solutions regardless of growing medium composition and time of analysis. Due to Hg accumulation and translocation as well as its potential leaching in acidic and neutral solution, compost can be recommended as a soil amendment during the phytoextraction of mercury-contaminated soil.

Bioremediation of lead contaminated soil with Rhodobacter sphaeroides.

Science.gov (United States)

Li, Xiaomin; Peng, Weihua; Jia, Yingying; Lu, Lin; Fan, Wenhong

2016-08-01

Bioremediation with microorganisms is a promising technique for heavy metal contaminated soil. Rhodobacter sphaeroides was previously isolated from oil field injection water and used for bioremediation of lead (Pb) contaminated soil in the present study. Based on the investigation of the optimum culturing conditions and the tolerance to Pb, we employed the microorganism for the remediation of Pb contaminated soil simulated at different contamination levels. It was found that the optimum temperature, pH, and inoculum size for R. sphaeroides is 30-35 °C, 7, and 2 × 10(8) mL(-1), respectively. Rhodobacter sphaeroides did not remove the Pb from soil but did change its speciation. During the bioremediation process, more available fractions were transformed to less accessible and inert fractions; in particular, the exchangeable phase was dramatically decreased while the residual phase was substantially increased. A wheat seedling growing experiment showed that Pb phytoavailability was reduced in amended soils. Results inferred that the main mechanism by which R. sphaeroides treats Pb contaminated soil is the precipitation formation of inert compounds, including lead sulfate and lead sulfide. Although the Pb bioremediation efficiency on wheat was not very high (14.78% root and 24.01% in leaf), R. sphaeroides remains a promising alternative for Pb remediation in contaminated soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

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)

Ecological Role of Soils upon Radioactive Contamination

Science.gov (United States)

Tsvetnov, Evgeny; Shcheglov, Alexei; Tsvenova, Olga

2016-04-01

The ecological role of soils upon radioactive contamination is clearly manifested in the system of notions about ecosystems services, i.e., benefits gained by humans from ecosystems and their components, including soils (Millennium Ecosystem Assessment, 2005). For the soils, these services are considered on the basis of soil functions in the biosphere that belong to the protective ecosystem functions within the group of soil functions known under the names of "Buffer and protective biogeocenotic shield" (at the level of particular biogeocenoses) and "Protective shield of the biosphere" (at the global biospheric level) (according to Dobrovol'skii & Nikitin, 2005). With respect to radionuclides, this group includes (1) the depositing function, i.e., the accumulation and long-term sequestration of radioactive substances by the soil after atmospheric fallout; (2) the geochemical function, i.e., the regulation of horizontal and vertical fluxes of radionuclides in the system of geochemically conjugated landscapes and in the soil-groundwater and soil-plant systems; and (3) the dose-forming function that is manifested by the shielding capacity of the soil with respect to the external ionizing radiation (lowering of the dose from external radiation) and by the regulation of the migration of radionuclides in the trophic chain (lowering of the dose from internal radiation). The depositing and geochemical functions of the soils are interrelated, which is seen from quantitative estimates of the dynamics of the fluxes of radionuclides in the considered systems (soil-plant, soil-groundwater, etc.). The downward migration of radionuclides into the lower soil layers proceeds very slowly: for decades, more than 90% of the pool of radionuclides is stored in the topmost 10 cm of the soil profile. In the first 3-5 years after the fallout, the downward migration of radionuclides with infiltrating water flows decreases from several percent to decimals and hundredths of percent from the

Pilot-scale feasibility of petroleum hydrocarbon-contaminated soil in situ bioremediation

International Nuclear Information System (INIS)

Walker, J.F. Jr.; Walker, A.B.

1995-01-01

An environmental project was conducted to evaluate in situ bioremediation of petroleum hydrocarbon-contaminated soils on Kwajalein Island, a US Army Kwajalein Atoll base in the Republic of the Marshall Islands. Results of laboratory column studies determined that nutrient loadings stimulated biodegradation rates and that bioremediation of hydrocarbon-contaminated soils at Kwajalein was possible using indigenous microbes. The column studies were followed by an ∼10-month on-site demonstration at Kwajalein to further evaluate in situ bioremediation and to determine design and operating conditions necessary to optimize the process. The demonstration site contained low levels of total petroleum hydrocarbons (diesel fuel) in the soil near the ground surface, with concentrations increasing to ∼10,000 mg/kg in the soil near the groundwater. The demonstration utilized 12 in situ plots to evaluate the effects of various combinations of water, air, and nutrient additions on both the microbial population and the hydrocarbon concentration within the treatment plots as a function of depth from the ground surface

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

Bioavailability and mobility of organic contaminants in soil: new three-step ecotoxicological evaluation.

Science.gov (United States)

Prokop, Zbyněk; Nečasová, Anežka; Klánová, Jana; Čupr, Pavel

2016-03-01

A novel approach was developed for rapid assessment of bioavailability and potential mobility of contaminants in soil. The response of the same test organism to the organic extract, water extract and solid phase of soil was recorded and compared. This approach was designed to give an initial estimate of the total organic toxicity (response to organic extractable fraction), as well as the mobile (response to water extract) and bioavailable fraction (response to solid phase) of soil samples. Eighteen soil samples with different levels of pollution and content of organic carbon were selected to validate the novel three-step ecotoxicological evaluation approach. All samples were chemically analysed for priority contaminants, including aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCH) and dichlordiphenyltrichloroethane (DDT). The ecotoxicological evaluation involved determination of toxicity of the organic, mobile and bioavailable fractions of soil to the test organism, bacterium Bacillus cereus. We found a good correlation between the chemical analysis and the toxicity of organic extract. The low toxicity of water extracts indicated low water solubility, and thus, low potential mobility of toxic contaminants present in the soil samples. The toxicity of the bioavailable fraction was significantly greater than the toxicity of water-soluble (mobile) fraction of the contaminants as deduced from comparing untreated samples and water extracts. The bioavailability of the contaminants decreased with increasing concentrations of organic carbon in evaluated soil samples. In conclusion, the three-step ecotoxicological evaluation utilised in this study can give a quick insight into soil contamination in context with bioavailability and mobility of the contaminants present. This information can be useful for hazard identification and risk assessment of soil-associated contaminants. Graphical Abstract New three-step ecotoxicological

Screening of plants for phytoremediation of oil-contaminated soil.

Science.gov (United States)

Ikeura, Hiromi; Kawasaki, Yu; Kaimi, Etsuko; Nishiwaki, Junko; Noborio, Kosuke; Tamaki, Masahiko

2016-01-01

Several species of ornamental flowering plants were evaluated regarding their phytoremediation ability for the cleanup of oil-contaminated soil in Japanese environmental conditions. Thirty-three species of plants were grown in oil-contaminated soil, and Mimosa, Zinnia, Gazania, and cypress vine were selected for further assessment on the basis of their favorable initial growth. No significant difference was observed in the above-ground and under-ground dry matter weight of Gazania 180 days after sowing between contaminated and non-contaminated plots. However, the other 3 species of plants died by the 180th day, indicating that Gazania has an especially strong tolerance for oil-contaminated soil. The total petroleum hydrocarbon concentration of the soils in which the 4 species of plants were grown decreased by 45-49% by the 180th day. Compared to an irrigated plot, the dehydrogenase activity of the contaminated soil also increased significantly, indicating a phytoremediation effect by the 4 tested plants. Mimosa, Zinnia, and cypress vine all died by the 180th day after seeding, but the roots themselves became a source of nutrients for the soil microorganisms, which led to a phytoremediation effect by increase in the oil degradation activity. It has been indicated that Gazania is most appropriate for phytoremediation of oil-contaminated soil.

CSOIL 2000 an exposure model for human risk assessment of soil contamination. A model description

NARCIS (Netherlands)

Brand E; Otte PF; Lijzen JPA; LER

2007-01-01

This RIVM description of the CSOIL 2000 model deals, for the first time, with all aspects of the model. CSOIL 2000 can be used to derive intervention values. Intervention values are calculated for contaminated soil and represent a measure for determining when contaminated soil needs to be

Assessment of contaminant lability during phytoremediation of polycyclic aromatic hydrocarbon impacted soil

Energy Technology Data Exchange (ETDEWEB)

Zakia D. Parrish; M. Katherine Banks; A. Paul Schwab [Connecticut Agricultural Experiment Station, New Haven, CT (United States). Department of Soil and Water

2005-09-15

Polycyclic aromatic hydrocarbons (PAHs) are recalcitrant compounds, some of which are known carcinogens, often found in high residual soil concentrations at industrial sites. Recent research has confirmed that phytoremediation holds promise as a low-cost treatment method for PAH contaminated soil. In this study, the lability of soil bound PAHs in the rhizosphere was estimated using solid phase extraction resin. An extraction time of 14 days was determined to be appropriate for this study. Resin-extractable PAHs, which are assumed to be more bioavailable, decreased during plant treatments. Significant reductions in the labile concentrations of several PAH compounds occurred over 12 months of plant growth. The differences in concentration between the unplanted and the planted soil indicate that the presence of plant roots, in addition to the passage of time, contributes to reduction in the bioavailability of target PAHs. The lability of sorbed contaminants is modified by the presence of plants. Remediation coupled with plant treatment can change the bioavailability of contaminants in soil.

Assessment of contaminant lability during phytoremediation of polycyclic aromatic hydrocarbon impacted soil

Energy Technology Data Exchange (ETDEWEB)

Parrish, Zakia D. [Department of Soil and Water, Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511 (United States); Banks, M. Katherine [School of Civil Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47907-2051 (United States)]. E-mail: kbanks@ecn.purdue.edu; Schwab, A. Paul [Department of Agronomy, Purdue University, 915 W. State Street, West Lafayette, IN 47907-2054 (United States)

2005-09-15

Polycyclic aromatic hydrocarbons (PAHs) are recalcitrant compounds, some of which are known carcinogens, often found in high residual soil concentrations at industrial sites. Recent research has confirmed that phytoremediation holds promise as a low-cost treatment method for PAH contaminated soil. In this study, the lability of soil bound PAHs in the rhizosphere was estimated using solid phase extraction resin. An extraction time of 14 days was determined to be appropriate for this study. Resin-extractable PAHs, which are assumed to be more bioavailable, decreased during plant treatments. Significant reductions in the labile concentrations of several PAH compounds occurred over 12 months of plant growth. The differences in concentration between the unplanted and the planted soil indicate that the presence of plant roots, in addition to the passage of time, contributes to reduction in the bioavailability of target PAHs. - The lability of sorbed contaminants is modified by the presence of plants. Remediation coupled with plant treatment can change the bioavailability of contaminants in soil.

Assessment of contaminant lability during phytoremediation of polycyclic aromatic hydrocarbon impacted soil

International Nuclear Information System (INIS)

Parrish, Zakia D.; Banks, M. Katherine; Schwab, A. Paul

2005-01-01

Polycyclic aromatic hydrocarbons (PAHs) are recalcitrant compounds, some of which are known carcinogens, often found in high residual soil concentrations at industrial sites. Recent research has confirmed that phytoremediation holds promise as a low-cost treatment method for PAH contaminated soil. In this study, the lability of soil bound PAHs in the rhizosphere was estimated using solid phase extraction resin. An extraction time of 14 days was determined to be appropriate for this study. Resin-extractable PAHs, which are assumed to be more bioavailable, decreased during plant treatments. Significant reductions in the labile concentrations of several PAH compounds occurred over 12 months of plant growth. The differences in concentration between the unplanted and the planted soil indicate that the presence of plant roots, in addition to the passage of time, contributes to reduction in the bioavailability of target PAHs. - The lability of sorbed contaminants is modified by the presence of plants. Remediation coupled with plant treatment can change the bioavailability of contaminants in soil

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.

Soil contamination studies

International Nuclear Information System (INIS)

1997-06-01

The objective of this project was to develop a quick screening method that accurately identifies and quantifies the amount of alpha-emitting radionuclides in infinitely-thick soil samples using a Frisch grid ionization chamber. An additional objective of the work was to provide the US Department of Energy, Nevada Operations Office and its contractors with information on the theoretical and actual measured results of atmospheric testing contamination of soil and water at the Nevada Test Site through a comprehensive search of existing literature

Statistical sampling strategies for survey of soil contamination

NARCIS (Netherlands)

Brus, D.J.

2011-01-01

This chapter reviews methods for selecting sampling locations in contaminated soils for three situations. In the first situation a global estimate of the soil contamination in an area is required. The result of the surey is a number or a series of numbers per contaminant, e.g. the estimated mean

Purification of soil contaminated by oil with microorganisms

Directory of Open Access Journals (Sweden)

Maira Kazankapova

2013-05-01

Full Text Available The paper presents the results of studying the influence of strains of Pseudomonas mendoсina H-3 and Oscillatoria С-3 on soil contaminated with petroleum and hydrocarbons. The changes in chemical composition of hydrocarbons were determined. The influence of strain on the soil was studied by IR spectroscopy and chromatography. It was found that microorganisms can break down paraffinic and aromatic petroleum hydrocarbons.

Effects of past copper contamination and soil structure on copper leaching from soil

DEFF Research Database (Denmark)

Paradelo, M; Møldrup, Per; Arthur, Emmanuel

2013-01-01

Copper contamination affects biological, chemical, and physical soil properties and associated ecological functions. Changes in soil pore organization as a result of Cu contamination can dramatically affect flow and contaminant transport in polluted soils. This study assessed the influence of soil...... structure on the movement of water and Cu in a long-term polluted soil. Undisturbed soil cores collected along a Cu gradient (from about 20 to about 3800 mg Cu kg−1 soil) were scanned using X-ray computed tomography (CT). Leaching experiments were performed to analyze tracer transport, colloid leaching......, and dissolved organic carbon (DOC) and Cu losses. The 5% arrival time (t0.05) and apparent dispersivity (λapp) for tracer breakthrough were calculated by fitting the experimental data to a nonparametric, double-lognormal probability density function. Soil bulk density, which did not follow the Cu gradient...

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.)

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)

Bioremediation of soil contaminated crude oil by Agaricomycetes.

Science.gov (United States)

Mohammadi-Sichani, M Maryam; Assadi, M Mazaheri; Farazmand, A; Kianirad, M; Ahadi, A M; Ghahderijani, H Hadian

2017-01-01

One of the most important environmental problems is the decontamination of petroleum hydrocarbons polluted soil, particularly in the oil-rich country. Bioremediation is the most effective way to remove these pollutants in the soil. Spent mushroom compost has great ability to decompose lignin-like pollution. The purpose of this study was the bioremediation of soil contaminated with crude oil by an Agaricomycetes . Soil sample amended with spent mushroom compost into 3%, 5% and 10% (w/w) with or without fertilizer. Ecotoxicity germination test was conducted with Lipidium sativa . The amplified fragment (18 s rDNA) sequence of this mushroom confirmed that the strain belonged to Pleurotus ostreatus species with complete homology (100% identity). All tests experiment sets were effective at supporting the degradation of petroleum hydrocarbons contaminated soil after three months. Petroleum contaminated soil amended with Spent mushroom compost 10% and fertilizer removed 64.7% of total petroleum hydrocarbons compared control. The germination index (%) in ecotoxicity tests ranged from 60.4 to 93.8%. This showed that the petroleum hydrocarbons contaminated soil amended with 10% Spent mushroom compost had higher bioremediation ability and reduced soil toxicity in less than three months.

Application of biodegradation screening protocol to contaminated soils from manufactured gas plant sites

International Nuclear Information System (INIS)

Smith, J.R.; Nakles, D.V.; Cushey, M.A.; Morgan, D.J.; Linz, D.G.

1990-01-01

Bioremediation (i.e., land treatment) has been demonstrated to be a viable option for treating a variety of soils contamianted with organics. Conventional treatability studies utilize soil microcosm experiments to evaluate the potential for bioremediation of specific contaminated soils. Unfortunately, soil microcosms take from 4- to 6-months to complete and do not fully exploit the current understanding of the bioremediation process. This paper describes a treatability protocol that investigates underlying mechanisms and can be completed in 2- to 3-months. It is believed that soil bioremediation is governed by the sequential processes of contanate desorption from the soil into the aqueous phase and subsequent oxidation by microorganisms. The relative importance of each process depends upon the contaminant and soil. Accordingly, the treatability protocol has three steps. In the first step, tests are performed to determine soil characteristics. In the second step, tests are performed to characterize the desorption of contaminants from the soil. In the third step, the potential for biological oxidaiton is evaluated with a soil-water slurry reactor that maximizes desorption and provides an optimum environment for microbial growth. This paper provides a thorough discussion of the laboratory protocol including the primary theoretical tenets which serve as its basis. Preliminary procedures and results are presented for soils contaminated with manufactured gas plant (MGP) wastes. Particular attention is focused on biodegradation of polynuclear aromatic hydrocarbons (PAHs)

Evaluation of hydrophobicity in PAH-contaminated soils during phytoremediation

International Nuclear Information System (INIS)

Cofield, Naressa; Banks, M. Katherine; Schwab, A. Paul

2007-01-01

The impact of recalcitrant organic compounds on soil hydrophobicity was evaluated in contaminated soil from a manufactured gas plant site following 12 months of phytoremediation. Significant reduction in soil wetting and water retention was observed in contaminated soil compared to an uncontaminated control. Phytoremediation was effective at reducing total PAHs by 69% with corresponding changes in soil classification from extremely hydrophobic (initial sample) to moderately-strongly hydrophobic (planted) and hydrophilic-very hydrophilic (unplanted) after 12 months. The greatest reduction in soil hydrophobicity was observed in the unplanted, unfertilized treatments that had the lowest removal rate of PAHs. The presence of plants may contribute to hydrophobicity in contaminated soil. - The presence of recalcitrant hydrophobic organic pollutants may enhance soil hydrophobicity

Leaching study of contaminated and remediated soil and dredged sludge and development of a fast testing procedure for determining the leachability of contaminants; Uitloogonderzoek aan verontreinigde en gereinigde grond en baggerspecie en ontwikkeling van verkorte proceudres ter bepaling van de uitloging

Energy Technology Data Exchange (ETDEWEB)

Zevenbergen, C.; Frapporti, G.; Keyzer, J.; Heynen, J.J.M.

1997-08-01

A large study, performed jointly by ECN and IWACO, in which the effect of soil remediation on the leachability of contaminants from soils was investigated, is summarized. The study included two specific aims, which are treated in more detail in two separate reports: (1) The development of a fast testing procedure for determining the leachability of pollutants from contaminated and treated soils, which allows for an assessment relative to the regulatory limits stated in the Dutch Building Materials Decree; and (2) To develop a better understanding of the physico-chemical processes underlying the leachability of contaminants, including the development of a model for the leaching of pollutants from contaminated and treated soils and dredged sludge. The development of a fast testing procedure is reported in this report. The study of physico-chemical processes is reported in `Speciation of metals in contaminated and remediated soil and dredged sludge. Leaching processes and controlling factors` (ECN-C--96-084). The contaminants dealt with in this report are arsenic, copper, cadmium, mercury, lead, zinc, and cyanide, as well as a limited amount of contaminated and remediated aquatic sediments. 13 figs., 2 tabs, 8 refs.

Zinc species distribution in EDTA-extract residues of zinc-contaminated soil

International Nuclear Information System (INIS)

Chang, S.-H.; Wei, Y.-L.; Wang, H. Paul

2007-01-01

Soil sample from a site heavily contaminated with >10 wt.% zinc is sampled and extracted with aqueous solutions of ethylene diamine tetra-acetic acid (EDTA) that is a reagent frequently used to extract heavy metals in soil remediation. Three liquid/soil ratios (5/1, 20/1, and 100/1) were used in the extracting experiment. The molecular environment of the residual Zn in the EDTA-extract residues of zinc-contaminated soil is investigated with XANES technique. The results indicate that EDTA does not show considerable preference of chelating for any particular Zn species during the extraction. Zn species distribution in the sampled soil is found to resemble that in all EDTA-extract residues; Zn(OH) 2 is determined as the major zinc species (60-70%), seconded by organic zinc (21-26%) and zinc oxide (9-14%)

Dissipation and phytoremediation of polycyclic aromatic hydrocarbons in freshly spiked and long-term field-contaminated soils.

Science.gov (United States)

Wei, Ran; Ni, Jinzhi; Li, Xiaoyan; Chen, Weifeng; Yang, Yusheng

2017-03-01

Pot experiments were used to compare the dissipation and phytoremediation effect of alfalfa (Medicago sativa L.) for polycyclic aromatic hydrocarbons (PAHs) in a freshly spiked soil and two field-contaminated soils with different soil organic carbon (SOC) contents (Anthrosols, 1.41% SOC; Phaeozems, 8.51% SOC). In spiked soils, the dissipation rates of phenanthrene and pyrene were greater than 99.5 and 94.3%, respectively, in planted treatments and 95.0 and 84.5%, respectively, in unplanted treatments. In field-contaminated Anthrosols, there were limited but significant reductions of 10.2 and 15.4% of total PAHs in unplanted and planted treatments, respectively. In field-contaminated Phaeozems, there were no significant reductions of total PAHs in either unplanted or planted treatments. A phytoremediation effect was observed for the spiked soils and the Anthrosols, but not for the Phaeozems. The results indicated that laboratory tests with spiked soils cannot reflect the real state of field-contaminated soils. Phytoremediation efficiency of PAHs in field-contaminated soils was mainly determined by the content of SOC. Phytoremediation alone has no effect on the removal of PAHs in field-contaminated soils with high SOC content.

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

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.

Interactive effects of Cd and PAHs on contaminants removal from co-contaminated soil planted with hyperaccumulator plant Sedum alfredii

Energy Technology Data Exchange (ETDEWEB)

Wang, Kai; Huang, Huagang; Li, Tingqiang; Yang, Xiaoe [Zhejiang Univ., Hangzhou (China). MOE Key Lab. of Environment Remediation and Ecosystem Health; Zhu, Zhiqiang [Zhejiang Univ., Hangzhou (China). MOE Key Lab. of Environment Remediation and Ecosystem Health; Hainan Univ., Haikou (China). College of Agriculture; He, Zhenli [Florida Univ., Port Pierce, FL (United States). Inst. of Food and Agricultural Sciences; Alva, Ashok [US Department of Agriculture, Prosser, WA (United States). Agricultural Research Service

2012-04-15

Purpose: Soil contamination by multiple organic and inorganic contaminants is common but its remediation by hyperaccumulator plants is rarely reported. The growth of a cadmium (Cd) hyperaccumulator Sedum alfredii and removal of contaminants from Cd and polycyclic aromatic hydrocarbons (PAHs) co-contaminated soil were reported in this study. Materials and methods: Soil slightly contaminated by Cd (0.92 mg kg{sup -1} DW) was collected from a vegetable field in Hangzhou and was spiked with two levels (0 and 6 mg kg{sup -1} DW) of Cd and three levels (0, 25, and 150 mg kg{sup -1} DW) of phenanthrene (PHE) or pyrene (PYR). A pot experiment was conducted in a greenhouse using S. alfredii with unplanted controls for 60 days. Shoot and root biomass of plants, dehydrogenase activity (DHA), and microbial biomass carbon in the soil were measured. Concentrations of Cd and PAHs in the plant and soil were determined. Results and discussion: Elevated Cd level (6.38 mg kg{sup -1} DW) increased S. alfredii growth. The presence of PAHs decreased the stimulatory effects of Cd on plant biomass and Cd concentrations in shoots in Cd spiked soil, thus decreasing Cd phytoextraction efficiency. Cadmium removal by S. alfredii after 60 days of growth varied from 5.8% to 6.7% and from 5.7% to 9.6%, in Cd unspiked and spiked soils, respectively. Removal rate of PAHs in the soil was similar with or without the plants. Removal rate of PYR decreased at the elevated Cd level in the soil. This appears to be due to a decrease in soil microbial activity. This is confirmed by a decrease in DHA, which is a good indicator of soil microbial activity. Conclusions: Our results demonstrate that S. alfredii could effectively extract Cd from Cd-contaminated soils in the presence of PHE or PYR; however, both PAHs exhibited negative effects on phytoextraction of Cd from Cd spiked soil (6.38 mg kg{sup -1} DW). S. alfredii is not suitable for remediation of PAHs. The effects of Cd and PAHs concentrations on the

The role of soil quality maps in the reuse of lightly contaminated soil

NARCIS (Netherlands)

Lamé, F.P.J.; Leenaers, H.; Zegwaard, J.

2000-01-01

In 1999 the Dutch government agreed on a new policy regarding the reuse of lightly contaminated soil. From now on, lightly contaminated soil may be reused under conditions of soil-quality management. The municipal authorities supervise the reuse under this new regime. Two basic criteria need to be

Measurement of radioactive soil contamination from the air

International Nuclear Information System (INIS)

Loman, A.C.; Kuile, C.R. ter; Slaper, H.

1990-09-01

In-situ gamma spectrometry can be used to determine the qualitative and quantitative deposition of radioactive materials on the ground surface. By applying the in-situ spectrometry method using either a helicopter or an airplane, large areas can be scanned in a short period of time. In this report the results of in-situ gamma spectroscopic measurements taken from a helicopter are described. Measurements were carried out using a single point source, a field of 36 point sources, and using the present ground contamination due to fall-out from the Chernobyl accident and atom bombs. The results of these measurements were used to determine calibration factors, which were in agreement with a calibration obtained using more simple (and less expensive) laboratory measurements in combination with flux calculations. Detection limits for the measurement of surface contamination were determined. At a height of 50 meters above the surface and using a measurement time of 2 minutes, the minimally detectable surface contamination was 1.1 kBqm -2 for a Cs-137 contamination and 2.1 kBqm -2 for I-131 contamination. Fall-out determinations based on measurements taken at a height of 50 meters were in agreement with determinations taken at a height of 1 meter, and with the results obtained measuring soil samples. The in-situ gamma spectroscopy, using helicopter or airplane, is a fast and powerful method for mapping surface contamination. (author). 13 refs.; 18 figs.; 13 tabs

Surfactant screening of diesel-contaminated soil

International Nuclear Information System (INIS)

Peters, R.W.; Montemagno, C.D.; Shem, L.; Lewis, B.-A.

1992-01-01

At one installation in California, approximately 60,000 gal of No. 2 diesel fuel leaked into the subsurface environment, resulting in contamination at depths from 6 to 34 m below the surface. Argonne National Laboratory was contracted to perform treatability studies for site remediation. This paper summarizes a surfactant screening/surfactant flooding research program in which 22 surfactants were screened for their effectiveness in mobilizing the organics from the contaminated soil prior to bioremediation. Anionic surfactants resulted in the greatest degree of diesel mobilization. The most promising surfactants will be employed on contaminated soil samples obtained from the site

Sorption of BTX mixtures to contaminated and uncontaminated site soils

International Nuclear Information System (INIS)

Uchrin, C.G.; Koshy, K.; Wojtenko, I.

1995-01-01

Both adsorption and desorption studies are being performed examining benzene, toluene, and meta-xylene (BTX) as single components, binary mixtures, and trinary mixture onto both existing contaminated soils as well as some uncontaminated reference soils. The contaminated soils were obtained from an oil refinery site and another industrial site in New Jersey. The oil refinery site soil did not exhibit significant amounts of either benzene, toluene or xylene but was contaminated with other compounds while the other industrial site soil was contaminated with toluene among other compounds. The organic carbon content of the soils ranged from 0.14 to 2.91 percent. Preliminary adsorption studies showed BTX to strongly sorb to these soils. The adsorption studies onto the reference soils also demonstrated the effect of organic matter on adsorption. Sequential batch desorption studies show the BTX to desorb quickly, reaching equilibrium within 48 hours. Long-term uptake and release were not noted with these soil/contaminant systems

A soil washing pilot plant for removing petroleum hydrocarbons from contaminated soils

International Nuclear Information System (INIS)

Toor, I.A.; Roehrig, G.R.

1992-01-01

A soil washing pilot plant was built and tested for its ability to remove petroleum hydrocarbons from certain soils. The ITEX soil washing pilot plant is a trailer mountable mobile unit which has a washing capacity of two tons per hour of contaminated soils. A benchscale study was carried out prior to the fabrication of the pilot plant. The first sample was contaminated with diesel fuel while the second sample was contaminated with crude oil. Various nonionic, cationic and anionic cleaning agents were evaluated for their ability to remove petroleum hydrocarbons from these materials. The nonionic cleaning agents were more successful in cleaning the soils in general. The ultimate surfactant choice was based on several factors including cost, biodegradability, cleaning efficiency and other technical considerations. The soil samples were characterized in terms of their particle size distributions. Commercial diesel fuel was carefully mixed in this sand to prepare a representative sample for the pilot plant study. Two pilot runs were made using this material. A multistage washing study was also conducted in the laboratory which indicates that the contamination level can be reduced to 100 ppm using only four stages. Because the pilot plant washing efficiency is twice as high, it is believed that ultimate contamination levels can be reduced to lower levels using the same number of stages. However, this hypothesis has not been demonstrated to date

Heavy metal movement in metal-contaminated soil profiles

Energy Technology Data Exchange (ETDEWEB)

Li, Zhenbin; Shuman, L.M. [Univ. of Georgia, Griffin, GA (United States)

1996-10-01

Heavy metal movement in soil profiles is a major environmental concern because even slow transport through the soil may eventually lead to deterioration of groundwater quality. In this study, three metal-contaminated soil (Fuquay, Dothan, and Clarendon) were selected from cropland were a high-metal flue dust had been applied annually for 6 years to raise soil pH, with application ending 4 years before sampling. One uncontaminated soil (Tifton) from the same physiographic area was also sampled as a control. Soil samples were collected in 15-cm increments from the surface to 105 cm in depth. Total contents of Zn, Cd, and Pb in the soils samples were determined. To better understand metal movement in relation to metal fractions in the soil profile, soil samples were also extracted sequentially for exchangeable (EXC), organic matter (OM), Mn oxide (MNO), amorphous Fe oxide (AFEO), crystalline Fe oxide (CFEO), and residual (RES) fractions. 35 refs., 6 figs., 2 tabs.

Diversity of bacterial communities along a petroleum contamination gradient in desert soils.

Science.gov (United States)

Abed, Raeid M M; Al-Kindi, Sumaiya; Al-Kharusi, Samiha

2015-01-01

Microbial communities in oil-polluted desert soils have been rarely studied compared to their counterparts from freshwater and marine environments. We investigated bacterial diversity and changes therein in five desert soils exposed to different levels of oil pollution. Automated rRNA intergenic spacer (ARISA) analysis profiles showed that the bacterial communities of the five soils were profoundly different (analysis of similarities (ANOSIM), R = 0.45, P pollution levels. Multivariate analyses of ARISA profiles revealed that the microbial communities in the S soil, which contains the highest level of contamination, were different from the other soils and formed a completely separate cluster. A total of 16,657 ribosomal sequences were obtained, with 42-89 % of these sequences belonging to the phylum Proteobacteria. While sequences belonging to Betaproteobacteria, Gammaproteobacteria, Bacilli, and Actinobacteria were encountered in all soils, sequences belonging to anaerobic bacteria from the classes Deltaproteobacteria, Clostridia, and Anaerolineae were only detected in the S soil. Sequences belonging to the genus Terriglobus of the class Acidobacteria were only detected in the B3 soil with the lowest level of contamination. Redundancy analysis (RDA) showed that oil contamination level was the most determinant factor that explained variations in the microbial communities. We conclude that the exposure to different levels of oil contamination exerts a strong selective pressure on bacterial communities and that desert soils are rich in aerobic and anaerobic bacteria that could potentially contribute to the degradation of hydrocarbons.

Soil moisture effects during bioventing in fuel-contaminated arid soils

International Nuclear Information System (INIS)

Zwick, T.C.; Leeson, A.; Hinchee, R.E.; Hoeppel, R.E.; Bowling, L.

1995-01-01

This study evaluated the effects of soil moisture addition on microbial activity during bioventing of dry, sandy soils at the Marine Corps Air Ground Combat Center (MCAGCC), Twentynine Palms, California. Soils at the site have been contaminated to a depth of approximately 80 ft (24 m) with gasoline, JP-5 jet fuel, and diesel fuel. Based on the low soil moisture measured at the site (2 to 3% by weight), it was determined that soil moisture may be limiting biodegradation. To evaluate the effect that moisture addition had on microbial activity under field conditions, a subsurface drip irrigation system was installed above the fuel hydrocarbon plume. Irrigation water was obtained from two monitoring wells on the site, where groundwater was approximately 192 ft (59 m) below ground surface. Advancement of the wetting front was monitored. In situ respiration rates increased significantly after moisture addition. The results of this study provide evidence for the potential applicability of moisture addition in conjunction with bioventing for site remediation in arid environments. Further work is planned to investigate optimization of moisture addition

Lead immobilization and phosphorus availability in phosphate-amended, mine-contaminated soils.

Science.gov (United States)

Osborne, Lydia R; Baker, Leslie L; Strawn, Daniel G

2015-01-01

Over a century of mining activities in the Coeur d'Alene mining district in Idaho have contaminated soils of the downstream basin with lead, arsenic, zinc, and cadmium. Elevated soil-Pb levels are a significant hazard to the health of humans and wildlife in the region. One in situ treatment approach for remediating Pb-contaminated soils is application of phosphorus to promote the formation of lead phosphate minerals that have low solubility. However, this remediation strategy may result in excess P runoff to surface waters, which can lead to eutrophication, particularly when used in riparian areas. Research presented in this paper describes experiments in which monopotassium phosphate (KHPO) solution was applied to two Pb-contaminated soils from the Coeur d'Alene River valley to determine how P loading rates affect both Pb immobilization and P mobility and to determine if an optimal P amendment rate can be predicted. Toxicity characteristic leaching procedure extractions were used to assess changes in Pb availability for uptake by an organism or mobilization through the soil, and Bray extractions were used to assess P availability for leaching out of the soil system. For the two soils tested, increasing phosphate amendment caused decreasing Pb extractability. Phosphorus amendment rates above approximately 70 mg kg, however, did not provide any additional Pb immobilization. Phosphorus availability increased with increasing phosphate application rate. An empirical relationship is presented that predicts extractable Pb as a function of extractable P. This relationship allows for prediction of the amount of Pb that can be immobilized at specified P leaching amounts, such as regulatory levels that have been established to minimize risks for surface water degradation. Results suggest that phosphate can be used to immobilize Pb in contaminated wetland or riparian areas without posing risks of P loading to surface waters. Copyright © by the American Society of Agronomy

Bioavailability of barium to plants and invertebrates in soils contaminated by barite.

Science.gov (United States)

Lamb, Dane T; Matanitobua, Vitukawalu P; Palanisami, Thavamani; Megharaj, Mallavarapu; Naidu, Ravi

2013-05-07

Barium (Ba) is a nonessential element to terrestrial organisms and is known to be toxic at elevated concentrations. In this study, the bioavailability and toxicity of Ba in barite (BaSO4) contaminated soils was studied using standard test organisms (Lactuca sativa L. "Great Lakes", Eisenia fetida). Contamination resulted from barite mining activities. Barium concentrations in contaminated soils determined by X-ray fluorescence were in the range 0.13-29.2%. Barite contaminated soils were shown to negatively impact both E. fetida and L. sativa relative to control soil. For E. fetida, pore-water concentrations and acid extractable Ba were linearly related to % body weight loss. In L. sativa, pore-water Ba and exchangeable Ba were both strongly related to shoot Ba and shoot biomass production. A negative linear relationship was observed between shoot Ba content and shoot weight (P Barium concentrations in pore-water were lower than predicted from barite solubility estimates but strongly related to exchangeable Ba, indicating an influence of ion exchange on Ba solubility and toxicity to E. fetida and L. sativa.

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.

Bioleaching of arsenic in contaminated soil using metal-reducing bacteria

Science.gov (United States)

Lee, So-Ra; Lee, Jong-Un; Chon, Hyo-Taek

2014-05-01

A study on the extraction of arsenic in the contaminated soil collected from an old smelting site in Korea was carried out using metal-reducing bacteria. Two types of batch-type experiments, biostimulation and bioaugmentation, were conducted for 28 days under anaerobic conditions. The biostimulation experiments were performed through activation of indigenous bacteria by supply with glucose or lactate as a carbon source. The contaminated, autoclaved soil was inoculated with metal-reducing bacteria, Shewanella oneidensis MR-1 and S. algae BrY, in the bioaugmentation experiments. The results indicated that the maximum concentration of the extracted As was 11.2 mg/L at 4 days from the onset of the experiment when 20 mM glucose was supplied and the extraction efficiency of As ranged 60~63% in the biostimulation experiments. In the case of bioaugmentation, the highest dissolved As concentration was 24.4 mg/L at 2 days, though it dramatically decreased over time through re-adsorption onto soil particles. After both treatments, mode of As occurrence in the soil appeared to be changed to readily extractable fractions. This novel technique of bioleaching may be practically applied for remediation of As-contaminated soil after determination of optimum operational conditions such as operation time and proper carbon source and its concentration.

Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type

DEFF Research Database (Denmark)

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

2015-01-01

Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero...... nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used...... as windows sealants. Saponin, a natural surfactant, was also tested to increase the PCB desorption from soils and enhance dechlorination. Remediation of Soil 1 (with highest pH, carbonate content, organic matter and PCB concentrations) obtained the maximum 83% and 60% PCB removal with the two...

Potential of different AM fungi (native from As-contaminated and uncontaminated soils) for supporting Leucaena leucocephala growth in As-contaminated soil.

Science.gov (United States)

Schneider, Jerusa; Bundschuh, Jochen; Rangel, Wesley de Melo; Guilherme, Luiz Roberto Guimarães

2017-05-01

Arbuscular mycorrhizal (AM) fungi inoculation is considered a potential biotechnological tool for an eco-friendly remediation of hazardous contaminants. However, the mechanisms explaining how AM fungi attenuate the phytotoxicity of metal(oid)s, in particular arsenic (As), are still not fully understood. The influence of As on plant growth and the antioxidant system was studied in Leucaena leucocephala plants inoculated with different isolates of AM fungi and exposed to increasing concentrations of As (0, 35, and 75 mg dm -3 ) in a Typic Quartzipsamment soil. The study was conducted under greenhouse conditions using isolates of AM fungi selected from uncontaminated soils (Acaulospora morrowiae, Rhizophagus clarus, Gigaspora albida; and a mixed inoculum derived from combining these isolates, named AMF Mix) as well as a mix of three isolates from an As-contaminated soil (A. morrowiae, R. clarus, and Paraglomus occultum). After 21 weeks, the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) were determined in the shoots in addition to measuring plant height and mineral contents. In general, AM fungi have shown multiple beneficial effects on L. leucocephala growth. Although the activity of most of the stress-related enzymes increased in plants associated with AM fungi, the percentage increase caused by adding As to the soil was even greater for non-mycorrhizal plants when compared to AM-fungi inoculated ones, which highlights the phytoprotective effect provided by the AM symbiosis. The highest P/As ratio observed in AM-fungi plants, compared to non-mycorrhizal ones, can be considered a good indicator that the AM fungi alter the pattern of As(V) uptake from As-contaminated soil. Our results underline the role of AM fungi in increasing the tolerance of L. leucocephala to As stress and emphasize the potential of the symbiosis L. leucocephala-R. clarus for As-phytostabilization at moderately As-contaminated

Enhanced ex-situ bioremediation of soil contaminated with ...

African Journals Online (AJOL)

contaminated soil. Thus, the objective of this study was to investigate the feasibility and effectiveness of using electrical biostimulation processes to enhance ex-situ bioremediation of soils contaminated with organic pollutants. The effect of ...

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

Radioactivity measurement of radioactive contaminated soil by using a fiber-optic radiation sensor

Science.gov (United States)

Joo, Hanyoung; Kim, Rinah; Moon, Joo Hyun

2016-06-01

A fiber-optic radiation sensor (FORS) was developed to measure the gamma radiation from radioactive contaminated soil. The FORS was fabricated using an inorganic scintillator (Lu,Y)2SiO5:Ce (LYSO:Ce), a mixture of epoxy resin and hardener, aluminum foil, and a plastic optical fiber. Before its real application, the FORS was tested to determine if it performed adequately. The test result showed that the measurements by the FORS adequately followed the theoretically estimated values. Then, the FORS was applied to measure the gamma radiation from radioactive contaminated soil. For comparison, a commercial radiation detector was also applied to measure the same soil samples. The measurement data were analyzed by using a statistical parameter, the critical level to determine if net radioactivity statistically different from background was present in the soil sample. The analysis showed that the soil sample had radioactivity distinguishable from background.

The removal of plutonium contaminants from Rocky Flats Plant soil

International Nuclear Information System (INIS)

Sunderland, N.R.

1987-01-01

This research was undertaken to determine if the TRUclean process could effectively remove radioactive elements from soils other than derived coral. This is an interim report prior to the project report and discusses the outcome of the tests of the Rocky Flats Plant (RFP) soil. The soil tested contained plutonium particulates in the micron and submicron range. Volume reduction and activity removal were accomplished with an overall efficiency of greater than 90%. The TRUclean process is a very practical and economical solution to soil contamination problems at the Rocky Flats Plant

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.

The effect of mycorrhizal inoculation on hybrid poplar fine root dynamics in hydrocarbon contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Gunderson, J.; Knight, J.D.; Van Rees, K.C.J. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Soil Science

2006-07-01

The biological remediation of contaminated soils using plants was discussed. Hybrid poplars are good candidates for phytoremediation because they root deeply, cycle large amounts of water and grow quickly. Their fine root system is pivotal in nutrient and water acquisition. Therefore, in order to maximize the phytoremediation potential, it is important to understand the response of the fine root system. In addition to degrading organic chemicals, ectomycorrhizal (ECM) fungi provide the host with greater access to nutrients. This study determined the relationship between residual soil hydrocarbons and soil properties at a field site. The effects of residual contamination on hybrid poplar fine root dynamics was also examined along with the effect of ectomycorrhizal colonization on hybrid poplar fine root dynamics when grown in diesel contaminated soil under controlled conditions. A minirhizotron camera inside a growth chamber captured images of mycorrhizal inoculation on hybrid poplar fine root production. Walker hybrid poplar seedlings were grown for 12 weeks in a control soil and also in a diesel contaminated soil. Seedlings were also grown in control and diesel contaminated, ectomycorrhizal inoculated soils. The inoculum was a mycorrhizal mix containing Pisolithus tinctorius and Rhizopogon spp. The images showed that colonization by ECM fungi increased hybrid poplar fine root production and aboveground biomass in a diesel contaminated soil compared to non-colonized trees in the same soil. Root:shoot ratios were much higher in the diesel contaminated/non-inoculated treatment than in either of the control soil treatments. Results of phytoremediation in diesel contaminated soil were better in the non-colonized treatment than in the colonized treatment. Both treatments removed more contaminants from the soil than the unplanted control. Much higher quantities of hydrocarbons were found sequestered in the roots from the inoculated treatment than from the non

Study of the trace metal ion influence on the turnover of soil organic matter in cultivated contaminated soils

International Nuclear Information System (INIS)

Dumat, C.; Quenea, K.; Bermond, A.; Toinen, S.; Benedetti, M.F.

2006-01-01

The role of metals in the behaviour of soil organic matter (SOM) is not well documented. Therefore, we investigated the influence of metals (Pb, Zn, Cu and Cd) on the dynamic of SOM in contaminated soils where maize (C 4 plant) replaced C 3 cultures. Three pseudogley brown leached soil profiles under maize with a decreasing gradient in metals concentrations were sampled. On size fractions, stable carbon isotopic ratio (δ 13 C), metals, organic carbon and nitrogen concentrations were measured in function of depth. The determined sequence for the amount of C 4 organic matter in the bulk fractions: M 3 (0.9) > M 2 (0.4) > M 1 (0.3) is in agreement with a significant influence of metals on the SOM turnover. New C 4 SOM, mainly present in the labile coarser fractions and less contaminated by metals than the stabilised C 3 SOM of the clay fraction, is more easily degraded by microorganisms. - Measure of δ 13 C and total metal concentrations in size fractions of contaminated soils suggests an influence of metals on the soil organic matter dynamic

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

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.

Biodegradation studies of diesel-contaminated soils and sediments

International Nuclear Information System (INIS)

Schlauch, M.; Clark, D.

1992-01-01

Radian Corporation is currently remediating the Atchison, Topeka and Sante Fe Railway Superfund site in Clovis, New Mexico. Biodegradation of the petroleum hydrocarbon-contaminated soils and sediments was chosen as the remedial alternative. In order to evaluate the optimum conditions for full-scale bioremediation at this site, Radian designed and implemented various laboratory and field studies. The initial laboratory treatability study was conducted to determine if hydrocarbons in both soils and sediments could be biodegraded using indigenous microorganisms, and determine that the soil were biodegradable, while the sediments were not due to inhibitory factors. To further evaluate the biodegradability6 of the sediments, a laboratory study was initiated which introduced chloride-resistant microbes. The study showed that the sediment bioremediation was possibly by utilizing these microbes; however, the cost was not favorable. Finally, a field plot study was initiated to determine how soil biodegradation would proceed in field conditions, to optimize influencing factors such as moisture and nutrient levels and bioseed addition, and to investigate alternate methods of bioremediating the sediments. Results showed that hydrocarbons in the soils biodegraded much faster in the field than in the lab, and that hydrocarbons in sediments applied to biotreated soils containing acclimated microorganisms were successfully biodegraded

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.)

Petroleum Contaminated Soil Treatment Using Surfactant and Hydrogen Peroxide

Directory of Open Access Journals (Sweden)

Ilza Lobo

2010-12-01

Full Text Available The process of washing soil with surfactants, sodium lauryl ether sulphate (LESS and sodium lauryl sulphate (SDS was combined with chemical oxidation using hydrogen peroxide, with a view to in situ remediation of clay soil contaminated with hydrocarbons oil. The evaluation of the efficiency of the procedure was the removal of polyaromatic hydrocarbons and the comparison of physical and chemical characteristics of contaminated soil and uncontaminated from the same region. The combination of these two techniques, soil washing and application of an oxidizing agent, presented as a process of effective remediation for soils contaminated with petroleum products in subtropical regions.

Phytoremediation of soils contaminated by cadmium

Science.gov (United States)

Watai, H.; Miyazaki, T.; Fujikawa, T.; Mizoguchi, M.

2004-12-01

Phytoremediation is a technique to clean up soils contaminated with heavy metals. Advantages of this method are that (1) This technique is suitable to cleanup soils slightly contaminated with heavy metals in relatively wide area. (2) The expense for clean up is lower than civil engineering techniques. (3) This method can remove heavy metals fundamentally from contaminated. (4) The heavy metals are able to recycle by ashing of plants. Many researches have been done on the phytoremediation up to now, but almost all these researches were devoted to clarify the phytoremediation from the view point of plants themselves. However, few efforts have been devoted to analyze the migrations of heavy metals in soils during the phytoremediation process. The objective of this study is to clarify the features of Cd migration when plant roots are absorbing Cd from the ambient soils. Especially, we focused on finding the Cd migration pattern by changing the soil condition such as plant growing periods, planting densities, and the initial Cd concentration in soils. We planted sunflowers in columns filled with Cd contaminated soils because sunflower is a well-known hyperaccumulator of Cd from soils. By cutting the shoots of plants at the soil surface, and by keeping the plant roots in the soils without disturbance, the Cd concentrations, moisture contents, pH distributions, EC distributions, and dry weight of residual roots in the soils were carefully analyzed. The experimental results showed that (1)The growth of the planted sunflowers were suffered by applying of Cd. (2)The decrease of suction was affected by water uptake by roots at the depth from 0 to 5 cm. Water contents with plants in soils decrease more than without plants. (3)Cd adsorption by roots was predominant within 5cm from soil surface. In addition, it was also shown that there was an optimal Cd concentration where Cd is most effectively adsorbed by the plant. In this experiment we found that 40 to 60 mg kg-1 was the

XRF analysis of soils contaminated by dust falls

International Nuclear Information System (INIS)

Marumo, Katsumi; Onoki, Yuka; Wada, Nobuhiko; Okano, Hideki

2013-01-01

Dust falls from the chimneys of waste incineration plants, coal-fired power plants, and refineries may contaminate soil over vast areas. Using an auger machine at 72 sites around a refinery in the Kanto area, Japan, we obtained 216 soil samples for a screening survey of potentially contaminated land. Qualitative and quantitative chemical analyses of zinc, lead, and cadmium were performed using a transmission X-ray fluorescence spectrometer (TXRF). X-ray fluorescence (XRF) chemical analytical data suggested that contaminated soil extends up to 3 km away from the chimneys of the refinery. Using calibration curves for the intensity ratios of Zn Kα X-ray to Mo Kβ Compton scatter X-ray [(Zn Kα)/(Mo-Kβ-Compton)], Pb Lβ X-ray to Mo-Kβ-Compton scatter X-ray [(Pb Lβ)/(Mo-Kβ-Compton)], and Cd Kα X-ray to Mo-Kβ Compton scatter X-ray [(Cd Kβ)/(Mo-Kβ-Compton)] of 30 reference materials, we obtained the Zn, Pb, and Cd concentrations of these 216 soil samples. The Pb and Cd concentrations from the XRF chemical analytical data were very similar to the Pb and Cd leachabilities determined by 1 M HC1 leaching test (MOE-approved method No. 19), suggesting that the chemical forms in which Pb and Cd occur are an adsorbed phase and a carbonate phase, which can be easily dissolved by 1 M HC1. XRF spectra of individual soil particles, obtained by spot-sized X-ray beams passed through a 1.5-mm-diameter and a 0.5-mm-diameter collimators, suggested that most of the soil fractions contained Zn and Pb. The levels of brightness of the X-ray images of these Zn- and Pb-bearing fractions were monitored with an X-ray CCD camera attached to the TXRF. Most of the soil fractions were transparent at the maximum X-ray tube voltage (50 kV), suggesting that the soil samples are suitable for the quantitative XRF chemical analysis of Zn and Pb. (author)

Assessment and Comparison of Electrokinetic and Electrokinetic-bioremediation Techniques for Mercury Contaminated Soil

Science.gov (United States)

Azhar, A. T. S.; Nabila, A. T. A.; Nurshuhaila, M. S.; Zaidi, E.; Azim, M. A. M.; Farhana, S. M. S.

2016-11-01

Landfills are major sources of contamination due to the presence of harmful bacteria and heavy metals. Electrokinetic-Bioremediation (Ek-Bio) is one of the techniques that can be conducted to remediate contaminated soil. Therefore, the most prominent bacteria from landfill soil will be isolated to determine their optimal conditions for culture and growth. The degradation rate and the effectiveness of selected local bacteria were used to reduce soil contamination. Hence, this enhances microbiological activities to degrade contaminants in soil and reduce the content of heavy metals. The aim of this study is to investigate the ability of isolated bacteria (Lysinibacillus fusiformis) to remove mercury in landfill soil. 5 kg of landfill soil was mixed with deionized water to make it into slurry condition for the purpose of electrokinetic and bioremediation. This remediation technique was conducted for 7 days by using 50 V/m of electrical gradient and Lysinibacillus fusiformis bacteria was applied at the anode reservoir. The slurry landfill soil was located at the middle of the reservoir while distilled water was placed at the cathode of reservoir. After undergoing treatment for 7 days, the mercury analyzer showed that there was a significant reduction of approximately up to 78 % of mercury concentration for the landfill soil. From the results, it is proven that electrokinetic bioremediation technique is able to remove mercury within in a short period of time. Thus, a combination of Lysinibacillus fusiformis and electrokinetic technique has the potential to remove mercury from contaminated soil in Malaysia.

Germination and initial growth of Campomanesia xanthocarpa O. Berg. (Myrtaceae, in petroleum-contaminated soil and bioremediated soil

Directory of Open Access Journals (Sweden)

AM. Gogosz

Full Text Available In 2000 there was an oil spill at the Getúlio Vargas Refinery (REPAR in Paraná. Nearly five years after contamination and the use of bioremediation, a study was carried out to identify the effects of the contaminated soil and the bioremediated soil on the germination and initial growth of C. xanthocarpa. The experiment was established with soil from REPAR, with three treatment groups: contaminated soil (C, bioremediated soil (B and uncontaminated soil (U; with five repetitions of 50 seeds each. There was no significant difference in the percentage of germination and the speed of germination index. The production of total biomass (30 - 60 days and shoot biomass (60 days was greater in the bioremediated soil compared to the other treatments. The averages for the root biomass were lower in the contaminated soil than in the bioremediated soil. The shoot length and the total length of the seedling in the contaminated soil and uncontaminated soil were lower than in the bioremediated soil.

Hybrid electrokinetic method applied to mix contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Mansour, H.; Maria, E. [Dept. of Building Civil and Environmental Engineering, Concordia Univ., Montreal (Canada)

2001-07-01

Several industrials and municipal areas in North America are contaminated with heavy metals and petroleum products. This mix contamination presents a particularly difficult task for remediation when is exposed in clayey soil. The objective of this research was to find a method to cleanup mix contaminated clayey soils. Finally, a multifunctional hybrid electrokinetic method was investigated. Clayey soil was contaminated with lead and nickel (heavy metals) at the level of 1000 ppm and phenanthrene (PAH) of 600 ppm. Electrokinetic surfactant supply system was applied to mobilize, transport and removal of phenanthrene. A chelation agent (EDTA) was also electrokinetically supplied to mobilize heavy metals. The studies were performed on 8 lab scale electrokinetic cells. The mix contaminated clayey soil was subjected to DC total voltage gradient of 0.3 V/cm. Supplied liquids (surfactant and EDTA) were introduced in different periods of time (22 days, 42 days) in order to optimize the most excessive removal of contaminants. The ph, electrical parameters, volume supplied, and volume discharged was monitored continuously during each experiment. At the end of these tests soil and cathalyte were subjected to physico-chemical analysis. The paper discusses results of experiments including the optimal energy use, removal efficiency of phenanthrene, as well, transport and removal of heavy metals. The results of this study can be applied for in-situ hybrid electrokinetic technology to remediate clayey sites contaminated with petroleum product mixed with heavy metals (e.g. manufacture Gas Plant Sites). (orig.)

Bioremediation of contaminated soil: Strategy and case histories

International Nuclear Information System (INIS)

Balba, M.T.; Ying, A.C.; McNeice, T.G.

1991-01-01

Microorganisms are capable of degrading many kinds of xenobiotic compounds and toxic chemicals. These microorganisms are ubiquitous in nature and there are numerous cases in which long-term contamination of soil and groundwater has been observed. The persistence of the contamination is usually caused by the inability of micro-organisms to metabolize these compounds under the prevailing environmental conditions. Two general reasons account for the failure of microbes to degrade pollutants in any environment: (1) inherent molecular recalcitrance of the contaminants and (2) environmental factors. The inherent molecular recalcitrance is usually associated with xenobiotic compounds where the chemical structure of the molecule is such that microbes and enzymes required for its catabolism have not evolved yet in nature. The environmental factors include a range of physicochemical conditions which influence microbial growth and activity. Biological remediation of contaminated sites can be accomplished using naturally-occurring microorganisms to treat the contaminants. Only particular groups of microorganisms are capable of decomposing specific compounds. The development of a bioremediation program for a specific contaminated soil system usually includes: thorough site/soil/waste characterization; treatability studies; and design and implementation of the bioremediation plan. The results of in situ and ex situ treatment programs involving the cleanup of petroleum hydrocarbon-contaminated soil will be discussed in detail. The paper will address key issues affecting the success of the bioremediation process such as nutrient transport, metal precipitation and potential soil clogging, microbial inoculation, etc

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.

Waste reduction by separation of contaminated soils during environmental restoration

International Nuclear Information System (INIS)

Roybal, J.A.; Conway, R.; Galloway, B.; Vinsant, E.; Slavin, P.; Guerin, D.

1998-06-01

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount of LLW and LLMW generated during the excavation process, SNL/NM is evaluating two alternative technologies. The first of these, the Segmented Gate System (SGS), is an automated system that located and removes gamma-ray emitting radionuclides from a host matrix (soil, sand, dry sludge). The matrix materials is transported by a conveyor to an analyzer/separation system, which segregates the clean and contaminated material based on radionuclide activity level. The SGS was used to process radioactively contaminated soil from the excavation of the Radioactive Waste Landfill. The second technology, Large Area Gamma Spectroscopy (LAGS), utilizes a gamma spec analyzer suspended over a slab upon which soil is spread out to a uniform depth. A counting period of approximately 30 minutes is used to obtain a full-spectrum analysis for the isotopes of interest. The LAGS is being tested on the soil that is being excavated from the Classified Waste Landfill

Solubility measurement of uranium in uranium-contaminated soils

International Nuclear Information System (INIS)

Lee, S.Y.; Elless, M.; Hoffman, F.

1993-08-01

A short-term equilibration study involving two uranium-contaminated soils at the Fernald site was conducted as part of the In Situ Remediation Integrated Program. The goal of this study is to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the equilibration study to predict the on-site uranium leaching and transport processes. The soluble levels of total uranium, calcium, magnesium, and carbonate increased continually for the first four weeks. After the first four weeks, these components either reached a steady-state equilibrium or continued linearity throughout the study. Aluminum, potassium, and iron, reached a steady-state concentration within three days. Silica levels approximated the predicted solubility of quartz throughout the study. A much higher level of dissolved uranium was observed in the soil contaminated from spillage of uranium-laden solvents and process effluents than in the soil contaminated from settling of airborne uranium particles ejected from the nearby incinerator. The high levels observed for soluble calcium, magnesium, and bicarbonate are probably the result of magnesium and/or calcium carbonate minerals dissolving in these soils. Geochemical modeling confirms that the uranyl-carbonate complexes are the most stable and dominant in these solutions. The use of carbonate minerals on these soils for erosion control and road construction activities contributes to the leaching of uranium from contaminated soil particles. Dissolved carbonates promote uranium solubility, forming highly mobile anionic species. Mobile uranium species are contaminating the groundwater underlying these soils. The development of a site-specific remediation technology is urgently needed for the FEMP site

Management and re-use of contaminated soils

International Nuclear Information System (INIS)

Nowicki, V.K.; LeBlanc, M.

1993-01-01

The volume occupied by petroleum-contaminated soils in landfill facilities could be totally eliminated by treatment of these soils in separate facilities. Once treated, the soils could be recycled. In New Brunswick, one such treatment facility was opened in 1992 adjacent to the Fredericton regional landfill site; a second site was opened near Moncton in 1992. These facilities receive petroleum-contaminated soil from such users as gasoline stations, bulk plants, institutions, and transport companies, as well as from oil spill sites. The types of contaminants present range from gasoline to heavy fuel oils and greases, and the soils can vary from clays to gravels. Incoming soils are layered on treatment pads and treated by bioremediation. A bionutrient mixture containing fertilizers plus an amount of adapted, naturally-occurring petroleum hydrocarbon degrading microorganisms is sprayed onto the pile layer by layer. Aeration tubing is also installed during this layering process. When the piles are complete, they are covered with black plastic and aerated. Bioremediation times vary from 10 to 24 weeks. The facility has successfully decontaminated over 20,000 tonnes of soil to date. The resulting soil can be used for such purposes as soil cover and backfill. The bioremediation process itself is portable and can be initiated at landfill sites themselves to reduce transport and handling costs. 16 refs., 4 figs

Micrometeorological methods for measurements of mercury emissions over contaminated soils

International Nuclear Information System (INIS)

Kim, K.H.; Lindberg, S.E.; Hanson, P.J.; Owens, J.; Myers, T.P.

1993-01-01

As part of a larger study involving development and application of field and laboratory methods (micrometeorological, dynamic enclosure chamber, and controlled laboratory chamber methods) to measure the air/surface exchange of Hg vapor, we performed a series of preliminary measurements over contaminated soils. From March--April 1993, we used the modified Bowen ratio (MBR) method to measure emission rates of mercury over a floodplain contaminated with mercury near Oak Ridge, TN. The mercury emission rates measured from contaminated EFPC soils using the MBR method during early spring show that (1) in all cases, the contaminated soils acted as a source of mercury to the atmosphere with source strengths ranging from 17 to 160 ng m -2 h -1 ; and (2) the strengths of mercury emissions can be greatly influenced by the combined effects of surface soil temperature, residence time of air masses over the source area, and turbulence conditions. The mercury fluxes measured in a controlled flow chamber indicate that contaminated soils can exhibit up to an order of magnitude higher emission rates of Hg under conditions of elevated soil temperature, soil structure disturbance, and high turbulence. Mercury emissions from contaminated soils exceeded emissions from background soils by one to two orders of magnitude

Development and application of techniques for monitoring the bioremediation of petroleum hydrocarbon-contaminated soils

International Nuclear Information System (INIS)

Greer, C.; Hawar, J.; Samson, R.

1994-01-01

A series of tests was designed to examine bioremediation potential in soil and to monitor performance during the treatment operation. Physical and chemical characterization of the soil provides information on the types of organics, their concentrations, and whether interfering materials are present. Microbiological assessment involves culturing of bacterial populations in the soil and examination of the colonies to determine which have the genetic potential to degrade the soil contaminants. Catabolic gene probes are used to survey viable bacteria from petroleum hydrocarbon contaminated soils. Such soils consistently demonstrate the presence of bacteria possessing the genetic capability to degrade simple straight-chain alkanes and aromatics. Mineralization and respirometric studies are indicators of the biological activity in the soil, and can be directed at microbial activity towards specific substrates. Gene probe monitoring of a petroleum hydrocarbon contaminated soil during biopile treatment demonstrated that hydrocarbon-degrading bacterial numbers and activity were temperature dependent. The results showed that the activity of the indigenous bacteria as measured by hexadecane mineralization also correlated with the disappearance of the oil and grease. The application of this protocol has provided a useful means to screen contaminated soils for bacteria with desirable catabolic properties and to monitor pollutant-degrading bacteria during biotreatment. 15 refs., 10 figs

Calculating the movement speed of a contaminated material in soil

International Nuclear Information System (INIS)

Lopez G, D.

2014-01-01

The present work describes the project which consisted in the development of an application to facilitate and display a graphic where the displacement and behavior of radioactive contaminants in soil could be observed. Once the data are introduced to the system, this makes the necessary calculations to display a graphic where the displacement of the substance is displayed in a given time. Through the graphs resulting from the program, we can quickly see the behavior and movement of a contaminant substance, but by numerical simulation, it can determine the possible impact caused by a supposition spills of a radioactive substance in soil and thus able to take the appropriate measures to control or avoid an impact resulting highly harmful to health and the environment, so as to determine the distance and time in which the substance already change or transform into another. (Author)

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.

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

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

Removal of residual contaminants in petroleum-contaminated soil by Fenton-like oxidation

Energy Technology Data Exchange (ETDEWEB)

Lu Mang [School of Material Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen, 333001, Jiangxi Province (China); State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Zhang Zhongzhi, E-mail: zzzhang1955@hotmail.com [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Qiao Wei; Guan Yueming; Xiao Meng; Peng Chong [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China)

2010-07-15

The degradation of bioremediation residues by hydrogen peroxide in petroleum-contaminated soil was investigated at circumneutral pH using a Fenton-like reagent (ferric ion chelated with EDTA). Batch tests were done on 20 g soil suspended in 60 mL aqueous solution containing hydrogen peroxide and Fe{sup 3+}-EDTA complex under constant stirring. A slurry reactor was used to treat the soil based on the optimal reactant conditions. Contaminants were characterized by Fourier transform infrared spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry. The results showed that the optimal treatment condition was: the molar ratio of hydrogen peroxide to iron = 200:1, and pH 7.0. Under the optimum condition, total dichloromethane-extractable organics were reduced from 14,800 to 2300 mg kg{sup -1} soil when the accumulative H{sub 2}O{sub 2} dosage was 2.45 mol kg{sup -1} soil during the reactor treatment. Abundance of viable cells was lower in incubated Fenton-like treated soil than in untreated soil. Oxidation of contaminants produced remarkable compositional and structural modifications. A fused ring compound, identified as C{sub 34}H{sub 38}N{sub 1}, was found to exhibit the greatest resistance to oxidation.

Phytotoxicity of trace metals in spiked and field-contaminated soils: Linking soil-extractable metals with toxicity.

Science.gov (United States)

Hamels, Fanny; Malevé, Jasmina; Sonnet, Philippe; Kleja, Dan Berggren; Smolders, Erik

2014-11-01

Soil tests have been widely developed to predict trace metal uptake by plants. The prediction of metal toxicity, however, has rarely been tested. The present study was set up to compare 8 established soil tests for diagnosing phytotoxicity in contaminated soils. Nine soils contaminated with Zn or Cu by metal mining, smelting, or processing were collected. Uncontaminated reference soils with similar soil properties were sampled, and series of increasing contamination were created by mixing each with the corresponding soil. In addition, each reference soil was spiked with either ZnCl2 or CuCl2 at several concentrations. Total metal toxicity to barley seedling growth in the field-contaminated soils was up to 30 times lower than that in corresponding spiked soils. Total metal (aqua regia-soluble) toxicity thresholds of 50% effective concentrations (EC50) varied by factors up to 260 (Zn) or 6 (Cu) among soils. For Zn, variations in EC50 thresholds decreased as aqua regia > 0.43 M HNO3  > 0.05 M ethylenediamine tetraacetic acid (EDTA) > 1 M NH4 NO3  > cobaltihexamine > diffusive gradients in thin films (DGT) > 0.001 M CaCl2 , suggesting that the last extraction is the most robust phytotoxicity index for Zn. The EDTA extraction was the most robust for Cu-contaminated soils. The isotopically exchangeable fraction of the total soil metal in the field-contaminated soils markedly explained the lower toxicity compared with spiked soils. The isotope exchange method can be used to translate soil metal limits derived from soils spiked with metal salts to site-specific soil metal limits. © 2014 SETAC.

Airborne soil particulates as vehicles for Salmonella contamination of tomatoes.

Science.gov (United States)

Kumar, Govindaraj Dev; Williams, Robert C; Al Qublan, Hamzeh M; Sriranganathan, Nammalwar; Boyer, Renee R; Eifert, Joseph D

2017-02-21

The presence of dust is ubiquitous in the produce growing environment and its deposition on edible crops could occur. The potential of wind-distributed soil particulate to serve as a vehicle for S. Newport transfer to tomato blossoms and consequently, to fruits, was explored. Blossoms were challenged with previously autoclaved soil containing S. Newport (9.39log CFU/g) by brushing and airborne transfer. One hundred percent of blossoms brushed with S. Newport-contaminated soil tested positive for presence of the pathogen one week after contact (PCompressed air was used to simulate wind currents and direct soil particulates towards blossoms. Airborne soil particulates resulted in contamination of 29% of the blossoms with S. Newport one week after contact. Biophotonic imaging of blossoms post-contact with bioluminescent S. Newport-contaminated airborne soil particulates revealed transfer of the pathogen on petal, stamen and pedicel structures. Both fruits and calyxes that developed from blossoms contaminated with airborne soil particulates were positive for presence of S. Newport in both fruit (66.6%) and calyx (77.7%). Presence of S. Newport in surface-sterilized fruit and calyx tissue tested indicated internalization of the pathogen. These results show that airborne soil particulates could serve as a vehicle for Salmonella. Hence, Salmonella contaminated dust and soil particulate dispersion could contribute to pathogen contamination of fruit, indicating an omnipresent yet relatively unexplored contamination route. Copyright © 2016 Elsevier B.V. All rights reserved.

Electrokinetic Amendment in Phytoremediation of Mixed Contaminated Soil

International Nuclear Information System (INIS)

Chirakkara, Reshma A.; Reddy, Krishna R.; Cameselle, Claudio

2015-01-01

This study examines the effects of electrokinetic amendments for phytoremediation of mixed contaminated soil where typical silty clay soil was spiked with organic contaminants (naphthalene and phenanthrene) and heavy metal (lead, cadmium and chromium). The contaminated soil was treated with compost and placed in electrokinetic cells, which were seeded with oat plant or sunflower. Thirty days after germination, 25 V alternating current was applied to selected cells using graphite electrodes for 3 h per day. The plants were harvested after a growth period of 61 days. One cell remained unplanted to evaluate the effect of the electric current on the soil, alone. The results confirm a significant reduction of heavy metals and organic contaminants in soil. However, there was no noticeable improvement of heavy metal phytoextraction or PAH degradation due to the application of electric field despite the increase in biomass production by the plants subjected to the electric current. The electric potential application time and frequency are suggested to be increased to have noticeable effects in heavy metal uptake and PAHs degradation.

Assessment of the bacterial community of soils contaminated with used lubricating oil by PCR-DGGE

Directory of Open Access Journals (Sweden)

Naruemon Meeboon

2016-12-01

Full Text Available The diversity of indigenous bacteria in three soils contaminated with used lubricating oil (ULO was determined and compared using molecular analysis of bacteria cultured during the enrichment process. Sequencing analyses demonstrated that the majority of the DGGE bands in enrichment cultures were affiliated with four phyla of the domain, Bacteria: α, β, γ- Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. Soil C had a higher ULO contamination level than soil A and B, which may explain why enrichment culture C had the greatest diversity of bacteria, but further studies would be needed to determine whether ULO concentration results in higher diversity of ULO-degraders in soils. The diversity of ULO-degraders detected in these three different soils suggests that biostimulation methods for increasing the activity of indigenous microorganisms may be a viable approach to bioremediation, and that future studies to determine how to increase their activity in situ are warranted.

COMPARATIVE ANALYSIS OF APPROACHES TO ECOLOGICAL ASSESSMENT OF POLYELEMENT CONTAMINATION SOIL OF URBAN ECOSYSTEM BY HEAVY METALS

Directory of Open Access Journals (Sweden)

YAKOVYSHYNA T. F.

2016-06-01

Full Text Available Raising of problem. In modern conditions, anthropogenic impact to the soil urban ecosystems is fairly stable over time and space, is manifested in various forms, as the transformation of the soil profile, the change in direction of the soil-forming processes, contamination of the various pollutants, and, above all, heavy metals (HM – elements of the first class of the danger. Their sources of the income to the urban environment are industrial enterprises, transport, housing and communal services. Determination of the anthropogenic pressure to the urban soil is carried out by the environmental assessment of the HM polyelement contamination, which allows to establish not only the fact of pollution, but also limits of the possible load with considering regional background or sanitary standards – MPC. However, until now discussions arise regarding the index which will be carried out the valuation – the cornerstone of any methodological approach to the environmental assessment of the soil polyelement contamination by the HM of the urban ecosystems, which allows to establish not only the fact of contamination, but also limits the possible load, taking into account the regional background or sanitary norm – MPC. Purpose. Lies in the grounded selection of the environmental assessment indexes of the soil contamination by the HM of the urban ecosystems through a comparative analysis of the existing approaches, such as the determination of the summary contamination index (SCI, the index of the soil contamination (ISC, factor imbalance (Sd, taking into account environmental safety standards and binding to the specific conditions territory. Conclusion. In summary it should be noted that it is necessary to use a set of integrated indexes, including the SCI to determine the violation of the metals content with respect to the geochemical background of zonal soil, ISC – link the contamination level with health indexes of the environmental safety

Surfactant-enhanced bioremediation of PAH- and PCB-contaminated soils

International Nuclear Information System (INIS)

Ghosh, M.M.; Yeom, I.T.; Shi, Z.; Cox, C.D.; Robinson, K.G.

1995-01-01

The role of surfactants in the desorption of soil-bound polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) was investigated. The solubilization of individual PAHs in an extract of a weathered, coal tar-contaminated soil containing a mixture of PAHs and other petroleum derivatives was found to be significantly less than that for pure compounds. Batch soil washing with Triton X-100 (a commercial, nonionic alkyl phenol ethoxylate) was found to increase the effective diffusion rate of PAHs from the contaminated soil by four orders of magnitude compared to that obtained by gas purging when the results were analyzed using a radial diffusion model. At concentrations of up to 24 times its critical micelle concentration (CMC), Triton X-100 did not seem to enhance hydrocarbon degradation in the coal tar-contaminated soil; however, the biosurfactant rhamnolipid R1, at a concentration of 50x CMC, increased the rate of mineralization of 4,4'-chlorinated biphenyl mobilized from a laboratory-contaminated soil by more than 60 times

Assessment of trace metal contamination of soils around Oluyole ...

African Journals Online (AJOL)

This study was carried out to determine the level of metals contamination of the soils around Oluyole industrial estate in Ibadan. Oluyole industrial estate has heavy concentration of manufacturing industries that generate a lot of waste products capable of introducing metals into the environment. Consequently, twenty-one ...

Assessment of trace metals contamination of soils around some ...

African Journals Online (AJOL)

This study was carried out to determine the level of soil contamination by metals around some automobile mechanic workshops in Oyo town in order to assess their possible adverse health implications on man and his environment. Concentrations of metals above certain levels have been shown to impair man's health.

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

Impact of clay mineral on air oxidation of PAH-contaminated soils.

Science.gov (United States)

Biache, Coralie; Kouadio, Olivier; Lorgeoux, Catherine; Faure, Pierre

2014-09-01

This work investigated the impact of a clay mineral (bentonite) on the air oxidation of the solvent extractable organic matters (EOMs) and the PAHs from contaminated soils. EOMs were isolated from two coking plant soils and mixed with silica sand or bentonite. These samples, as well as raw soils and bentonite/soil mixtures, were oxidized in air at 60 and 100 °C for 160 days. Mineralization was followed by measuring the CO2 produced over the experiments. EOM, polycyclic aromatic compound (PAC), including PAH, contents were also determined. Oxidation led to a decrease in EOM contents and PAH concentrations, these diminutions were enhanced by the presence of bentonite. Transfer of carbon from EOM to insoluble organic matter pointed out a condensation phenomenon leading to a stabilization of the contamination. Higher mineralization rates, observed during the oxidation of the soil/bentonite mixtures, seem to indicate that this clay mineral had a positive influence on the transformation of PAC into CO2.

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.

Ex-situ bioremediation of petroleum contaminated soil

International Nuclear Information System (INIS)

Minier, M.R.

1994-01-01

The use of stress acclimated bacteria and nutrient supplements to enhance the biodegradation of petroleum contaminated soil can be a cost effective and reliable treatment technology to reduce organic contaminant levels to below established by local, state, and federal regulatory clean-up criteria. This paper will summarize the results of a field study in which 12,000 yds 3 of petroleum contaminated soil was successfully treated via ex-situ bioremediation and through management of macro and micronutrient concentrations, as well as, other site specific environmental factors that are essential for optimizing microbial growth

Effect of manure, clay, charcoal, zeolite, and calcium oxide on some properties of soil contaminated with cobalt

Directory of Open Access Journals (Sweden)

Kosiorek Milena

2017-09-01

Full Text Available The study has been undertaken in order to determine the influence of different substances (manure, clay, charcoal, zeolite and calcium oxide on soil pH, hydrolytic acidity, total exchangeable bases, cation exchange capacity, the base saturation of soil contaminated with cobalt (0, 20, 40, 80, 160, 320 mg·kg−1 of soil. The analysed properties of soil proved to be dependent on the cobalt contamination and the kind of substances. In the series without substances soil contamination with the highest doses of cobalt raised the soil’s hydrolytic acidity but depressed its pH, total exchangeable bases and base saturation. Among the substances applied to soil in order to neutralize the effect of contamination with cobalt, calcium oxide had the strongest influence on the soil’s properties. In the series with calcium oxide application the hydrolytic acidity was decreased and other soil properties were increased. Manure addition to soil had positive but weaker effect on analysed soil properties.

Aircraft-borne spectrometry - a fast method for nuclide-specific measurement of soil contamination

International Nuclear Information System (INIS)

Winkelmann, I.; Schweiger, M.; Thomas, M.; Endrulat, H.J.

1991-01-01

An airworthy gamma spectrometer system for fast and large-area, nuclide-specific measurement of the soil contamination is described. The system encompasses an ultrapure germanium detector combined with a computer-controlled multichannel analyser system. The development from the laboratory system to an industrial-scale measuring system is explained. The practical testing is explained and first results are reported, obtained from measuring flights for the nuclide-specific determination of the soil contamination in the free State of Bavaria. (orig.) [de

Determination of amino acids in industrial effluents contaminated soil

International Nuclear Information System (INIS)

Mahar, M.T.; Khuhawar, M.Y.

2014-01-01

38 samples of soil for 19 locations partially irrigated on the effluents of sugar mill and oil andghee mill, bottom sediments of evaporation ponds of sugar and fertilizer industries were collected and analyzed for amino acids after acid digestion by gas chromatography using pre column derivatization with trifluroacetyleacetone and ethyl chloroformate. The results obtained were compared with the soil samples irrigated with fresh water. The soil samples were also analyzed for pH, total nitrogen contents and organic carbon. Nine essential (leucine (Leu), threonine (Thr), lysine (Lys), L-phenylalanine (Phe), tryptophan (Trp), histadine (His), L-valine (Val), methionine (Met) and isoleucine Ile) and ten non-essential ( alanine (Ala), cysteine (Cys), asparagine (Asn), glutamic acid (Glu), serine (Ser), glycine (Gly), proline (Pro), Glutamine (Gln), aspartic acid (Asp), tyrosine (Tyr)) amino acids were analyzed 13-15 amino acids were identified and determined quantitatively from soil samples. Amino acids Met, Asn, Gln and Trp were observed absent from all the samples. The variation in the amino acids contents in soil with the industrial effluents added and total nitrogen and organic carbon is discussed. (author)

Concept of Aided Phytostabilization of Contaminated Soils in Postindustrial Areas.

Science.gov (United States)

Radziemska, Maja; Koda, Eugeniusz; Bilgin, Ayla; Vaverková, Mgdalena D

2017-12-23

The experiment was carried out in order to evaluate the effects of trace element immobilizing soil amendments, i.e., chalcedonite, dolomite, halloysite, and diatomite on the chemical characteristics of soil contaminated with Cr and the uptake of metals by plants. The study utilized analysis of variance (ANOVA), principal component analysis (PCA) and Factor Analysis (FA). The content of trace elements in plants, pseudo-total and extracted by 0.01 M CaCl₂, were determined using the method of spectrophotometry. All of the investigated element contents in the tested parts of Indian mustard ( Brassica juncea L.) differed significantly in the case of applying amendments to the soil, as well as Cr contamination. The greatest average above-ground biomass was observed when halloysite and dolomite were amended to the soil. Halloysite caused significant increases of Cr concentrations in the roots. The obtained values of bioconcentration and translocation factors observed for halloysite treatment indicate the effectiveness of using Indian mustard in phytostabilization techniques. The addition of diatomite significantly increased soil pH. Halloysite and chalcedonite were shown to be the most effective and decreased the average Cr, Cu and Zn contents in soil.

Production of non-constructive concrete blocks using contaminated soil

NARCIS (Netherlands)

de Korte, A.C.J.; Brouwers, Jos

2009-01-01

In this research, a heavily contaminated humus-rich peat soil and a lightly contaminated humus-poor sand soil, extracted from a field location in the Netherlands, are immobilized. These two types of soil are very common in the Netherlands. The purpose is to develop financial feasible, good quality

Approaches to the prediction of radiocesium uptake by plants from contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Herren, T; Riesen, T [Paul Scherrer Institute, Dept. of Radiation Protection and Waste Management, Villigen (Switzerland)

1998-08-01

Our approaches are mainly focused in two directions: (1 ) Investigation in alternative methods for the determination of K{sub D} or other parameters characterizing the ratio between bound and dissolved radiocesium. The fraction of available radiocesium determined by the different methods is correlated with contents of plants grown on another sample of the same soil. (2) Search for a plant that combines high concentrations of cesium in the shoot with considerable biomass accumulation. Such a plant could be used for remediation of a contaminated site if it gets possible to increase the desorbed radiocesium from the clay minerals. Such a plant may also be used as a bioindicator of the effectively available radiocesium concentration of a contaminated soil

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)

Bioremediation of petroleum hydrocarbon contaminated soils using soil vapor extraction: Case study

International Nuclear Information System (INIS)

Roth, R.J.; Peterson, R.M.

1994-01-01

Soils contaminated with petroleum hydrocarbons are being remediated in situ at a site in Lakewood, New Jersey by bioremediation in conjunction with soil vapor extractions (SVE) and nutrient addition. The contaminants were from hydraulic oils which leaked from subsurface hydraulic lifts, waste oil from leaking underground storage tanks (USTs), an aboveground storage tank, and motor oil from a leaking UST. The oils contaminated subsurface soils at the site to a depth of 25 feet. Approximately 900 cubic yards of soil were contaminated. Soil sample analyses showed total petroleum hydrocarbon (TPH) concentrations up to 31,500 ppm. The design of the remedial system utilized the results of a treatability study which showed that TPH degrading microorganisms, when supplied with oxygen and nutrients, affected a 14% reduction in TPH in 30 days. A SVE system was installed which used three wells, each installed to a depth of 25 feet below grade. The SVE system was operated to achieve an extracted air flow of approximately 20 to 30 scfm from each well. Bioremediation of the TPH was monitored by measuring CO 2 and O 2 concentrations at the wellheads and vapor monitoring probes. After four months of remediation, CO 2 concentrations were at a minimum, at which point the subsurface soils were sampled and analyzed for TPH. The soil analyses showed a removal of TPH by biodegradation of up to 99.8% after four months of remediation

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

Removal of radium-226 from radium-contaminated soil using humic acid by column leaching method

International Nuclear Information System (INIS)

Esther Phillip; Muhamad Samudi Yasir

2012-01-01

In this study, evaluation of radium-226 removal from radium-contaminated soil using humic acid extracted from peat soil by column leaching method was carried out. Humic acid of concentration 100 ppm and pH 7 was leached through a column packed with radium-contaminated soil and leachates collected were analysed with gamma spectrometer to determine the leached radium-226. Results obtained indicated low removal of radium-226 between 1 - 4 %. Meanwhile, leaching profile revealed that radium-226 was bound to soil components with three different strength, thus resulting in three phases of radium-226 removal. It was estimated that the total removal of radium-226 from 10 g radium-contaminated soil sample studied could be achieved using approximately 31500 - 31850 ml HA solutions with leaching rate of 1 ml/ min. (author)

The effects of soil amendments on heavy metal bioavailability in two contaminated Mediterranean soils

Energy Technology Data Exchange (ETDEWEB)

Walker, D.J.; Clemente, Rafael; Roig, Asuncion; Bernal, M.P

2003-04-01

The effects of organic amendments on metal bioavailability were not always related to their degree of humification. - Two heavy metal contaminated calcareous soils from the Mediterranean region of Spain were studied. One soil, from the province of Murcia, was characterised by very high total levels of Pb (1572 mg kg{sup -1}) and Zn (2602 mg kg{sup -1}), whilst the second, from Valencia, had elevated concentrations of Cu (72 mg kg{sup -1}) and Pb (190 mg kg{sup -1}). The effects of two contrasting organic amendments (fresh manure and mature compost) and the chelate ethylenediaminetetraacetic acid (EDTA) on soil fractionation of Cu, Fe, Mn, Pb and Zn, their uptake by plants and plant growth were determined. For Murcia soil, Brassica juncea (L.) Czern. was grown first, followed by radish (Raphanus sativus L.). For Valencia soil, Beta maritima L. was followed by radish. Bioavailability of metals was expressed in terms of concentrations extractable with 0.1 M CaCl{sub 2} or diethylenetriaminepentaacetic acid (DTPA). In the Murcia soil, heavy metal bioavailability was decreased more greatly by manure than by the highly-humified compost. EDTA (2 mmol kg{sup -1} soil) had only a limited effect on metal uptake by plants. The metal-solubilising effect of EDTA was shorter-lived in the less contaminated, more highly calcareous Valencia soil. When correlation coefficients were calculated for plant tissue and bioavailable metals, the clearest relationships were for Beta maritima and radish.

Bioremediation of crude oil contaminated tea plantation soil using ...

African Journals Online (AJOL)

Crude oil contamination of soil is a major concern for tea industry in Assam, India. Crude oil is a persistent organic contaminant which alters soil physical and biochemical characteristics and makes tea plants more susceptible against crude oil contamination. Therefore, two native bacterial strains designated as AS 03 and ...

Feasilbility of phytoextraction to remediate cadmium and zinc contaminated soils

NARCIS (Netherlands)

Koopmans, G.F.; Romkens, P.F.A.M.; Fokkema, M.J.; Song, J.; Luo, Y.M.; Japenga, J.; Zhao, F.J.

2008-01-01

A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and

Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils

NARCIS (Netherlands)

Koopmans, G.F.; Romkens, P.F.A.M.; Fokkema, M.J.; Song, J.; Luo, Y.; Japenga, J.; Zhao, F.J.

2008-01-01

A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and

Soil mixing of stratified contaminated sands.

Science.gov (United States)

Al-Tabba, A; Ayotamuno, M J; Martin, R J

2000-02-01

Validation of soil mixing for the treatment of contaminated ground is needed in a wide range of site conditions to widen the application of the technology and to understand the mechanisms involved. Since very limited work has been carried out in heterogeneous ground conditions, this paper investigates the effectiveness of soil mixing in stratified sands using laboratory-scale augers. This enabled a low cost investigation of factors such as grout type and form, auger design, installation procedure, mixing mode, curing period, thickness of soil layers and natural moisture content on the unconfined compressive strength, leachability and leachate pH of the soil-grout mixes. The results showed that the auger design plays a very important part in the mixing process in heterogeneous sands. The variability of the properties measured in the stratified soils and the measurable variations caused by the various factors considered, highlighted the importance of duplicating appropriate in situ conditions, the usefulness of laboratory-scale modelling of in situ conditions and the importance of modelling soil and contaminant heterogeneities at the treatability study stage.

Bioremediation of diesel fuel contaminated soils

International Nuclear Information System (INIS)

Troy, M.A.; Jerger, D.E.

1992-01-01

Bioremediation techniques were successfully employed in the cost-effective cleanup of approximately 8400 gallons of diesel fuel which had been accidentally discharged at a warehouse in New Jersey. Surrounding soils were contaminated with the diesel fuel at concentrations exceeding 1,470 mg/kg total petroleum hydrocarbons as measured by infrared spectroscopy (TPH-IR, EPA method 418.1, modified for soils). This paper reports on treatment of the contaminated soils through enhanced biological land treatment which was chosen for the soil remediation pursuant to a New Jersey Pollutant Discharge Elimination System - Discharge to Ground Water (NJPDES-DGW) permit. Biological land treatment of diesel fuel focuses on the breakdown of the hydrocarbon fractions by indigenous aerobic microorganisms in the layers of soil where oxygen is made available. Metabolism by these microorganisms can ultimately reduce the hydrocarbons to innocuous end products. The purpose of biological land treatment was to reduce the concentration of the petroleum hydrocarbon constituents of the diesel fuel in the soil to 100 ppm total petroleum hydrocarbons (TPH)

Release behavior of triazine residues in stabilised contaminated soils

International Nuclear Information System (INIS)

Ying, G.G.; Kookana, R.S.; Mallavarpu, M.

2005-01-01

This paper reports the release behavior of two triazines (atrazine and simazine) in stabilised soils from a pesticide-contaminated site in South Australia. The soils were contaminated with a range of pesticides, especially with triazine herbicides. With multiple extractions of each soil sample with deionised water (eight in total), 15% of atrazine and 4% of simazine residues were recovered, resulting in very high concentrations of the two herbicides in leachate. The presence of small fractions of surfactants was found to further enhance the release of the residues. Methanol content up to 10% did not substantially influence the concentration of simazine and atrazine released. The study demonstrated that while the stabilisation of contaminated soil with particulate activated carbon (5%) and cement mix (15%) was effective in locking the residues of some pesticides, it failed to immobilise triazine herbicides residues completely. Given the higher water solubility of these herbicides than other compounds more effective strategies to immobilise their residues is needed. - Stabilisation of contaminated soil with a mix of activated carbon and cement may fail to immobilise some contaminants like triazines

Zinc fractionation in contaminated soils by sequential and single extractions: influence of soil properties and zinc content.

Science.gov (United States)

Voegelin, Andreas; Tokpa, Gerome; Jacquat, Olivier; Barmettler, Kurt; Kretzschmar, Ruben

2008-01-01

We studied the fractionation of zinc (Zn) in 49 contaminated soils as influenced by Zn content and soil properties using a seven-step sequential extraction procedure (F1: NH4NO3; F2: NH4-acetate, pH 6; F3: NH3OHCl, pH 6; F4: NH4-EDTA, pH 4.6; F5: NH4-oxalate, pH 3; F6: NH4-oxalate/ascorbic acid, pH 3; F7: residual). The soils had developed from different geologic materials and covered a wide range in soil pH (4.0-7.3), organic C content (9.3-102 g kg(-1)), and clay content (38-451 g kg(-1)). Input of aqueous Zn with runoff water from electricity towers during 26 to 74 yr resulted in total soil Zn contents of 3.8 to 460 mmol kg(-1). In acidic soils (n = 24; pH soils (n = 25; pH > or =6.0), most Zn was extracted in the mobilizable fraction (F2) and the intermediate fractions (F4 and F5). The extractability of Zn increased with increasing Zn contamination of the soils. The sum of mobile (F1) and mobilizable (F2) Zn was independent of soil pH, the ratio of Zn in F1 over F1+F2 plotted against soil pH, exhibited the typical shape of a pH sorption edge and markedly increased from pH 6 to pH 5, reflecting the increasing lability of mobilizable Zn with decreasing soil pH. In conclusion, the extractability of Zn from soils contaminated with aqueous Zn after decades of aging under field conditions systematically varied with soil pH and Zn content. The same trends are expected to apply to aqueous Zn released from decomposing Zn-bearing contaminants, such as sewage sludge or smelter slag. The systematic trends in Zn fractionation with varying soil pH and Zn content indicate the paramount effect of these two factors on molecular scale Zn speciation. Further research is required to characterize the link between the fractionation and speciation of Zn and to determine how Zn loading and soil physicochemical properties affect Zn speciation in soils.

Bioavailability assessment of contaminants in soils via respiration and nitrification tests

International Nuclear Information System (INIS)

Hund-Rinke, Kerstin; Simon, Markus

2008-01-01

For the assessment of contaminated soils ecotoxicological tests are used to estimate the bioavailability of contaminants in soil samples. Terrestrial tests reveal the habitat function of soils, and parameters applied in tests involving microorganisms include respiration activity and potential ammonium oxidation. For such tests, the threshold values needed to assess the results have already been established in guidelines ISO 17155 and ISO 15685. In this paper, we discuss about the respiration activity and potential ammonium oxidation results obtained from a wide variety of soils with different physico-chemical properties and levels of contamination. These results show that microbial respiration and potential ammonium oxidation have different sensitivities to various classes of contaminants. We demonstrated that both organic and inorganic contaminants influence potential ammonium oxidation, whereas microbial respiration is predominantly affected by biodegradable organic contaminants. These differences might be useful for more detailed assessments of soil contamination, leading to different recommended actions depending on which parameter is affected. - The paper provides a further criterion for a more detailed assessment of soil contamination, leading to different recommended actions depending on which parameter is affected

Bioavailability assessment of contaminants in soils via respiration and nitrification tests

Energy Technology Data Exchange (ETDEWEB)

Hund-Rinke, Kerstin [Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, 57392 Schmallenberg (Germany)], E-mail: kerstin.hund-rinke@ime.fraunhofer.de; Simon, Markus [Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, 57392 Schmallenberg (Germany)], E-mail: markus.simon@ime.fraunhofer.de

2008-05-15

For the assessment of contaminated soils ecotoxicological tests are used to estimate the bioavailability of contaminants in soil samples. Terrestrial tests reveal the habitat function of soils, and parameters applied in tests involving microorganisms include respiration activity and potential ammonium oxidation. For such tests, the threshold values needed to assess the results have already been established in guidelines ISO 17155 and ISO 15685. In this paper, we discuss about the respiration activity and potential ammonium oxidation results obtained from a wide variety of soils with different physico-chemical properties and levels of contamination. These results show that microbial respiration and potential ammonium oxidation have different sensitivities to various classes of contaminants. We demonstrated that both organic and inorganic contaminants influence potential ammonium oxidation, whereas microbial respiration is predominantly affected by biodegradable organic contaminants. These differences might be useful for more detailed assessments of soil contamination, leading to different recommended actions depending on which parameter is affected. - The paper provides a further criterion for a more detailed assessment of soil contamination, leading to different recommended actions depending on which parameter is affected.

SoilCAM: soil contamination: advanced integrated characterisation and time-lapse monitoring

NARCIS (Netherlands)

French, H.K.; Zee, van der S.E.A.T.M.; Meju, M.

2009-01-01

The SoilCAM project is aimed at improving current methods for monitoring contaminant distribution and biodegradation in the subsurface. Currently proven methods, based on invasive sampling of soil, soil water and gaseous phase, are unable to provide sufficiently accurate data with high enough

Urban community gardeners' knowledge and perceptions of soil contaminant risks.

Science.gov (United States)

Kim, Brent F; Poulsen, Melissa N; Margulies, Jared D; Dix, Katie L; Palmer, Anne M; Nachman, Keeve E

2014-01-01

Although urban community gardening can offer health, social, environmental, and economic benefits, these benefits must be weighed against the potential health risks stemming from exposure to contaminants such as heavy metals and organic chemicals that may be present in urban soils. Individuals who garden at or eat food grown in contaminated urban garden sites may be at risk of exposure to such contaminants. Gardeners may be unaware of these risks and how to manage them. We used a mixed quantitative/qualitative research approach to characterize urban community gardeners' knowledge and perceptions of risks related to soil contaminant exposure. We conducted surveys with 70 gardeners from 15 community gardens in Baltimore, Maryland, and semi-structured interviews with 18 key informants knowledgeable about community gardening and soil contamination in Baltimore. We identified a range of factors, challenges, and needs related to Baltimore community gardeners' perceptions of risk related to soil contamination, including low levels of concern and inconsistent levels of knowledge about heavy metal and organic chemical contaminants, barriers to investigating a garden site's history and conducting soil tests, limited knowledge of best practices for reducing exposure, and a need for clear and concise information on how best to prevent and manage soil contamination. Key informants discussed various strategies for developing and disseminating educational materials to gardeners. For some challenges, such as barriers to conducting site history and soil tests, some informants recommended city-wide interventions that bypass the need for gardener knowledge altogether.

Urban community gardeners' knowledge and perceptions of soil contaminant risks.

Directory of Open Access Journals (Sweden)

Brent F Kim

Full Text Available Although urban community gardening can offer health, social, environmental, and economic benefits, these benefits must be weighed against the potential health risks stemming from exposure to contaminants such as heavy metals and organic chemicals that may be present in urban soils. Individuals who garden at or eat food grown in contaminated urban garden sites may be at risk of exposure to such contaminants. Gardeners may be unaware of these risks and how to manage them. We used a mixed quantitative/qualitative research approach to characterize urban community gardeners' knowledge and perceptions of risks related to soil contaminant exposure. We conducted surveys with 70 gardeners from 15 community gardens in Baltimore, Maryland, and semi-structured interviews with 18 key informants knowledgeable about community gardening and soil contamination in Baltimore. We identified a range of factors, challenges, and needs related to Baltimore community gardeners' perceptions of risk related to soil contamination, including low levels of concern and inconsistent levels of knowledge about heavy metal and organic chemical contaminants, barriers to investigating a garden site's history and conducting soil tests, limited knowledge of best practices for reducing exposure, and a need for clear and concise information on how best to prevent and manage soil contamination. Key informants discussed various strategies for developing and disseminating educational materials to gardeners. For some challenges, such as barriers to conducting site history and soil tests, some informants recommended city-wide interventions that bypass the need for gardener knowledge altogether.

Pollution potential of oil-contaminated soil on groundwater resources in Kuwait

International Nuclear Information System (INIS)

Literathy, P.; Quinn, M.; Al-Rashed, M.

2003-01-01

The only natural freshwater resource of Kuwait occurs as lenses floating on the saline groundwater in the northern part of the country, near to the oil fields. Rainwater is the only means of recharge of this limited groundwater resource. This groundwater is used as bottled drinking water and the fresh groundwater aquifer is considered as a strategic drinking water reserve for Kuwait. As a result of the 1991 Gulf War, the upper soil layer has been widely contaminated with crude oil and crude oil combustion products, which are potential pollutants likely affecting the groundwater resources. Significant efforts have been made to assess this pollution. These included: (a) a soil survey for assessing the soil contamination, and (b) leaching experiments to characterise the mobilization of the soil-associated pollutants. Fluorescence measurement techniques were used during field surveys as well as for laboratory testing. In addition, determination of the total extractable matter (TEM), total petroleum hydrocarbons (TPH), and GC/MS measurement of polyaromatic hydrocarbons (PAHs) were performed for the assessments. The laser induced fluorescence (LIF) measurement, having good correlation with the other laboratory measurements, was proved to provide necessary information for the assessment of the oil-contamination level in the desert soil. The subsequent leaching test with water demonstrated the mobilization of the fluorescing compounds (e.g. PAHs), and the alteration in the leaching characteristics of the contamination during the long term environmental weathering of the oil. (author)

Improving the phytoremediation of heavy metals contaminated soil by use of sewage sludge.

Science.gov (United States)

Placek, Agnieszka; Grobelak, Anna; Kacprzak, Malgorzata

2016-01-01

Sewage sludge, in particular from the food industry, is characterized by fertilizing properties, due to the high content of organic matter and nutrients. The application of sewage sludge causes an improvement of soil parameters as well as increase in cation exchange capacity, and thus stronger binding of cations in the soil environment, which involves the immobilization of nutrients and greater resistance to contamination. In a field experiment sewage sludge has been used as an additive to the soil supporting the phytoremediation process of land contaminated with heavy metals (Cd, Zn, and Pb) using trees species: Scots pine (Pinus silvestris L.), Norway spruce (Picea abies L.), and oak (Quercus robur L.). The aim of the research was to determine how the application of sewage sludge into the soil surface improves the phytoremediation process. The conducted field experiment demonstrated that selected trees like Scots pine and Norway spruce, because of its excellent adaptability, can be used in the remediation of soil. Oak should not be used in the phytoremediation process of soils contaminated with high concentrations of trace elements in the soil, because a significant amount of heavy metals was accumulated in the leaves of oak causing a risk of recontamination.

Bio-mechanical removing of contaminated soils: a field experiment

International Nuclear Information System (INIS)

Jouve, A.; Maubert, H.; Schulte, E.

1992-01-01

If, in spite of safety precautions, a major nuclear accident would occur, countermeasures should be taken to attenuate the impact of radioactive deposits. The European RESSAC program (REhabilitation of Soils and Surfaces after an ACcident) aims at studying actions for normal life return in contaminated zones. One of them, called the Decontaminating Vegetal Network (D.V.N.) associates the biological action of turfing plants, producing a dense root-network capable to trap the top contaminated soil particles, and the mechanical efficiency of a turf harvester which can remove only 1 cm of soil. This performance, not associated with other techniques of soil removal such as scrapers or bulldozers, leads to minimize the waste production. The D.V.N is a vegetal cover spread over the contaminated soil, using the hydro-seeding technique. The growing plants are forming a pleasant lawn which may have a positive impact on the public opinion compared to techniques using bitumen mixtures to cover the soil. Field experiments involving labelling solutions of stable molybdenum salts simulating the contamination of the soil have shown that this technique can be applied as well on homogeneous cultivated soil surfaces as on roughly ploughed soils. 4 refs., 3 figs., 2 tabs

Electrokinetic In Situ Treatment of Metal-Contaminated Soil

Science.gov (United States)

Quinn, Jacqueline; Clausen, Christian A., III; Geiger, Cherie; Reinhart, Debra

2004-01-01

An electrokinetic technique has been developed as a means of in situ remediation of soils, sludges, and sediments that are contaminated with heavy metals. Examples of common metal contaminants that can be removed by this technique include cadmium, chromium, zinc, lead, mercury, and radionuclides. Some organic contaminants can also be removed by this technique. In the electrokinetic technique, a low-intensity direct current is applied between electrodes that have been implanted in the ground on each side of a contaminated soil mass. The electric current causes electro-osmosis and migration of ions, thereby moving aqueous-phase subsurface contaminants from one electrode to the other. The half reaction at the anode yields H+, thereby generating an acid front that travels from the anode toward the cathode. As this acid front passes through a given location, the local increase in acidity increases the solubility of cations that were previously adsorbed on soil particles. Ions are transported towards one electrode or the other which one depending on their respective electric charges. Upon arrival at the electrodes, the ionic contaminants can be allowed to become deposited on the electrodes or can be extracted to a recovery system. Surfactants and other reagents can be introduced at the electrodes to enhance rates of removal of contaminants. Placements of electrodes and concentrations and rates of pumping of reagents can be adjusted to maximize efficiency. The basic concept of electrokinetic treatment of soil is not new. What is new here are some of the details of application and the utilization of this technique as an alternative to other techniques (e.g., flushing or bioremediation) that are not suitable for treating soils of low hydraulic conductivity. Another novel aspect is the use of this technique as a less expensive alternative to excavation: The cost advantage over excavation is especially large in settings in which contaminated soil lies near and/or under

Effective dielectric mixture model for characterization of diesel contaminated soil

International Nuclear Information System (INIS)

Al-Mattarneh, H.M.A.

2007-01-01

Human exposure to contaminated soil by diesel isomers can have serious health consequences like neurological diseases or cancer. The potential of dielectric measuring techniques for electromagnetic characterization of contaminated soils was investigated in this paper. The purpose of the research was to develop an empirical dielectric mixture model for soil hydrocarbon contamination application. The paper described the basic theory and elaborated in dielectric mixture theory. The analytical and empirical models were explained in simple algebraic formulas. The experimental study was then described with reference to materials, properties and experimental results. The results of the analytical models were also mathematically explained. The proposed semi-empirical model was also presented. According to the result of the electromagnetic properties of dry soil contaminated with diesel, the diesel presence had no significant effect on the electromagnetic properties of dry soil. It was concluded that diesel had no contribution to the soil electrical conductivity, which confirmed the nonconductive character of diesel. The results of diesel-contaminated soil at saturation condition indicated that both dielectric constant and loss factors of soil were decreased with increasing diesel content. 15 refs., 2 tabs., 9 figs

Enhanced bioremediation of PAH-contaminated soil by immobilized bacteria with plant residue and biochar as carriers

Energy Technology Data Exchange (ETDEWEB)

Chen, Baoliang; Yuan, Miaoxin; Qian, Linbo [Zhejiang Univ., Hangzhou (China). Dept. of Environmental Science; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou (China)

2012-10-15

Polycyclic aromatic hydrocarbons (PAHs) are largely accumulated in soils in China. The immobilized-microorganism technique (IMT) is a potential approach for abating soil contamination with PAHs. However, few studies about the application of IMT to contaminated soil remediation were reported. Due to recalcitrance to decomposition, biochar application to soil may enhance soil carbon sequestration, but few studies on the application of biochars to remediation of contaminated soil were reported. In this study, we illustrated enhanced bioremediation of soil having a long history of PAH contamination by IMT using plant residues and biochars as carriers. Two PAH-degrading bacteria, Pseudomonas putida and an unidentified indigenous bacterium, were selected for IMT. The extractability and biodegradation of 15 PAHs in solution and an actual PAH-contaminated soil amended with immobilized-bacteria materials were investigated under different incubation periods. The effects of carriers and the molecular weight of PAHs on bioremediation efficiency were determined to illustrate their different bio-dissipation mechanisms of PAHs in soil. The IMT can considerably enhance the removal of PAHs. Carriers impose different effects on PAH bio-dissipation by amended soil with immobilized-bacteria, which can directly degrade the carrier-associated PAHs. The removal of PAHs from soil depended on PAH molecular weight and carrier types. Enhanced bio-dissipation by IMT was much stronger for 4- and 5-ring PAHs than for 3- and 6-ring ones in soil. Only P400 biochar-immobilized bacteria enhanced bio-dissipation of all PAHs in contaminated soil after a 90-day incubation. Biochar can promote bioremediation of contaminated soil as microbial carriers of IMT. It is vital to select an appropriate biochar as an immobilized carrier to stimulate biodegradation. It is feasible to use adsorption carriers with high sorptive capabilities to concentrate PAHs as well as microorganisms and thereby enhance

Landfarming of phthalate ester-contaminated soil: Two years of bioremediation results

International Nuclear Information System (INIS)

Kunze, C.M.; Yu, J.; Wilson, S.; Rezin, J.L.; Andronico, A.

1995-01-01

Biorem Technologies Inc. collaborated with Regal Plastics Corporation over 2 years to clean up approximately 600 cubic yards of soil contaminated with di-2-ethylhexyl phthalate ester (DEHP) and No. 2 fuel oil using a landfarming bioremediation process. The contaminated soils consisted of sandy backfill material which had been excavated during the removal of two underground storage tanks (USTs). In 1994, the initial average DEHP concentration was 4,551 ppm while the TPH concentration was 7,252 ppm. In 1995, the initial DEHP concentration was 1067 ppm while TPH was 3,733 ppm. Prior to the implementation of the project, Biorem Technologies completed a laboratory biofeasibility study to demonstrate that a bacterial culture isolated from the site had the capacity to efficiently degrade DEBP in the soil. It was determined during this study that nitrogen and phosphorus nutrient amendments were needed to promote the bioremediation process. In 1994, the soils were loaded on to a lined treatment bed to a depth of 14--16 in. The bed was covered with a greenhouse structure to eliminate stormwater runoff concerns associated with the contaminated soil. To optimize biodegradation, soil moisture and nutrient levels were adjusted. In 1995, a windrow turner replaced the 1994 tilling system. Tarps were used to cover the piles in place of the greenhouse. A leachate collection system was implemented to contain stormwater and leachate

Bioremediation of hydrocarbon-contaminated soils: are treatability and ecotoxicity endpoints related?

International Nuclear Information System (INIS)

Visser, S.

1999-01-01

To determine if there is a relationship between biotreatability and ecotoxicity endpoints in a wide range of hydrocarbon-contaminated soils, including medium and heavy crude oil-contaminated flare pit wastes and lubrication oil contaminated soil, research was conducted. Each test material was analyzed for pH, water repellency, electrical conductivity, available N and P, total extractable hydrocarbons, oil and grease, and toxicity to seedling emergence, root elongation in barley, lettuce and canola, earthworm survival and luminescent bacteria (Microtox), prior to, and following three months of bioremediation in the laboratory. By monitoring soil respiration, progress of the bioremediation process and determination of a treatment endpoint were assessed. The time required to attain a treatment endpoint under laboratory conditions can range from 30 days to 100 days depending on the concentration of hydrocarbons and degree of weathering. Most flare pits are biotreatable, averaging a loss of 25-30% of hydrocarbons during bioremediation. Once a treatment endpoint is achieved, residual hydrocarbons contents almost always exceeds Alberta Tier I criteria for mineral oil and grease. As a result of bioremediation treatments, hydrophobicity is often reduced from severe to low. Many flare pit materials are still moderately to extremely toxic after reaching a treatment endpoint. (Abstract only)

Phytoremediation of arsenic contaminated soil by arsenic accumulators: a three year study.

Science.gov (United States)

Raj, Anshita; Singh, Nandita

2015-03-01

To investigate whether phytoremediation can remove arsenic from the contaminated area, a study was conducted for three consecutive years to determine the efficiency of Pteris vittata, Adiantum capillus veneris, Christella dentata and Phragmites karka, on arsenic removal from the arsenic contaminated soil. Arsenic concentrations in the soil samples were analysed after harvesting in 2009, 2010 and 2011 at an interval of 6 months. Frond arsenic concentrations were also estimated in all the successive harvests. Fronds resulted in the greatest amount of arsenic removal. Root arsenic concentrations were analysed in the last harvest. Approximately 70 % of arsenic was removed by P. vittata which was recorded as the highest among the four plant species. However, 60 % of arsenic was removed by A. capillus veneris, 55.1 % by C. dentata and 56.1 % by P. karka of arsenic was removed from the contaminated soil in 3 years.

Bioremediation in soil contaminated with hydrocarbons in Colombia.

Directory of Open Access Journals (Sweden)

María Alejandra Trujillo Toro

2012-10-01

Full Text Available This study analyzes bioremediation processes of hydrocarbon contaminated soils in Colombia as a sustainable alternative to the deterioration of environmental quality by hydrocarbon spillage. According to national and international environmental law, all waste contaminated with hydrocarbons is considered dangerous waste, and therefore it cannot be released in the ground, water or be incinerated. Such legislation has motivated companies around the world to implement treatment processes for contaminated soils. Within Colombia, oil companies have been implementing the bioremediation of hydrocarbon contaminated soils in order to manage the waste coming from activities of oil drilling, refinement, transport and distribution.These practices must be considered viable for their ease of implementation, their low overhead costs, and for the benefits they provide towards environmental quality. Among the positive impacts that these practices have generated, it may consider the following: a solution for the problem of hydrocarbon contaminated soils, alternatives for the ultimate disposal of said waste without affecting ground, water or air resources, the low cost of the operation, and the technical experience of sustainable development which can continue to be implemented in companies dealing with dangerous waste.

Progress of research and utilization of soil amendments in phytoremediation of radioactive contamination soil

International Nuclear Information System (INIS)

Guo Yangrui; Song Gang; Chen Yongheng

2012-01-01

With the increasing of soil pollution and degradation, it becomes more important to research and apply soil amendments in agriculture. This paper reviewed different kinds of soil amendments and their impacts on phytostabilization and phytoextraction techniques, and summarized the application of soil amendments in the radio-contaminated soils as well as their effects on the phytoremediation. The main repair mechanisms of the soil amendments are involved in adsorption, ion exchange, chelation, and complexation. The potential applications in the phytoremediation on radio-contaminated soils, as well as the main repair mechanisms and the existing problems were discussed. (authors)

Vermiremediation of soils contaminated with mixture of petroleum ...

African Journals Online (AJOL)

In this paper, vermiremediation, a biological technique was utilized in order to clean-up soil contaminated with gasoline, diesel and spent engine oil using an earthworm - Eisenia fetida. The contaminated soils were analyzed for the total petroleum hydrocarbon (TPH) level every 24 hours over a period of 120 hours using ...

Heavy metal contamination of soil and sediment in Zambia

African Journals Online (AJOL)

USER

Key words: Heavy metal, contamination, mining, soil, sediment. INTRODUCTION ... drinking water and inhaling air or soil contaminated by mining activities and the ..... indicates that copper waste discharged into the upper reaches of the Kafue ...

Toxocara (Nematoda: Ascaridida and Other Soil-Transmitted Helminth Eggs Contaminating Soils in Selected Urban and Rural Areas in the Philippines

Directory of Open Access Journals (Sweden)

Vachel Gay V. Paller

2014-01-01

Full Text Available The extent of contamination of soils with soil transmitted helminthes (STH eggs, particularly Toxocara, was determined in selected urban and rural towns of Laguna, Philippines. Soil samples were collected from public schools, house yards, and empty lots. Results revealed that, of the 1480 soil samples collected, 460 (31% were positive for STH eggs. Toxocara sp. was the most prevalent (77%, followed by Ascaris sp. (11%, hookworms/strongyles/free-living nematodes (7%, and Trichuris sp. (5%. Some soil physicochemical parameters were also determined and associated with Toxocara eggs prevalence and density in soil. Results revealed that Toxocara sp. eggs were most prevalent in less acidic, relatively high temperature and high moisture soil conditions. They were also prevalent in sandy, silty, and loamy soil textures but less prevalent in clayey. No significant differences were found between depth 1 (0–5 cm and depth 2 (6–10 cm. This study revealed that Toxocara sp. eggs are ubiquitous and the extent of contamination in soils from the selected towns of Laguna is relatively high. Hence, the data generated in this study can be used in promoting public awareness, particularly for pet owners and local health officials, for effective prevention and control of this parasitosis.

Field-scale assessment of phytotreatment of soil contaminated with weathered hydrocarbons and heavy metals

Energy Technology Data Exchange (ETDEWEB)

Palmroth, M.R.T.; Koskinen, P.E.P.; Tuhkanen, T.A.; Puhakka, J.A. [Inst. of Environmental Engineering and Biotechnology, Tampere Univ. of Tech., Tampere (Finland); Pichtel, J. [Natural Resources and Environmental Management, Ball State Univ., Muncie, IN (United States); Vaajasaari, K. [Pirkanmaa Regional Environment Centre, Tampere (Finland); Joutti, A. [Finnish Environment Inst., Helsinki (Finland)

2006-08-15

Background, Aims, and Scope. Phytoremediation is remediation method which uses plants to remove, contain or detoxify environmental contaminants. Phytoremediation has successfully been applied for the removal of fresh hydrocarbon contamination, but removal of aged hydrocarbons has proven more difficult. Biodegradation of hydrocarbons in the subsurface can be enhanced by the presence of plant roots, i.e. the rhizosphere effect. Phytostabilization reduces heavy metal availability via immobilization in the rhizosphere. Soils contaminated by both hydrocarbons and heavy metals are abundant and may be difficult to treat. Heavy metal toxicity can inhibit the activity of hydrocarbon-degrading micro-organisms and decrease the metabolic diversity of soil bacteria. In this experiment, weathered hydrocarbon- and heavy metal-contaminated soil was treated using phytoremediation in a 39-month field study in attempts to achieve both hydrocarbon removal and heavy metal stabilization. Methods. A combination of hydrocarbon degradation and heavy metal stabilization was evaluated in a field-scale phytoremediation study of weathered contaminants. Soil had been contaminated over several years with hydrocarbons (11,400{+-}4,300 mg kg dry soil){sup -1} and heavy metals from bus maintenance activities and was geologically characterized as till. Concentrations of soil copper, lead and zinc were 170{+-}50 mgkg{sup -1}, 1,100{+-}1,500 mg kg{sup -1} and 390{+-} 340 mg kg{sup -1}, respectively. The effect of contaminants, plant species and soil amendment (NPK fertilizer or biowaste compost) on metabolic activity of soil microbiota was determined. Phytostabilization performance was investigated by analyses of metal concentrations in plants, soil and site leachate as well as acute toxicity to Vibrio fischeri and Enchtraeus albidus. Results. Over 39 months hydrocarbon concentrations did not decrease significantly (P=0.05) in non-amended soil, although 30% of initial hydrocarbon concentrations were

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.

A hierarchical approach to ecological assessment of contaminated soils at Aberdeen Proving Ground, USA

Energy Technology Data Exchange (ETDEWEB)

Kuperman, R.G.

1995-12-31

Despite the expansion of environmental toxicology studies over the past decade, soil ecosystems have largely been ignored in ecotoxicological studies in the United States. The objective of this project was to develop and test the efficacy of a comprehensive methodology for assessing ecological impacts of soil contamination. A hierarchical approach that integrates biotic parameters and ecosystem processes was used to give insight into the mechanisms that lead to alterations in the structure and function of soil ecosystems in contaminated areas. This approach involved (1) a thorough survey of the soil biota to determine community structure, (2) laboratory and field tests on critical ecosystem processes, (3) toxicity trials, and (4) the use of spatial analyses to provide input to the decision-making, process. This methodology appears to, offer an efficient and potentially cost-saving tool for remedial investigations of contaminated sites.

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.

Overcoming phytoremediation limitations. A case study of Hg contaminated soil

Science.gov (United States)

Barbafieri, Meri

2013-04-01

Phytoremediation is a broad term that comprises several technologies to clean up water and soil. Despite the numerous articles appearing in scientific journals, very few field applications of phytoextraction have been successfully realized. The research here reported on Phytoextraction, the use the plant to "extract" metals from contaminated soil, is focused on implementations to overcome two main drawbacks: the survival of plants in unfavorable environmental conditions (contaminant toxicity, low fertility, etc.) and the often lengthy time it takes to reduce contaminants to the requested level. Moreover, to overcome the imbalance between the technology's potential and its drawbacks, there is growing interest in the use of plants to reduce only the fraction that is the most hazardous to the environment and human health, that is to target the bioavailable fractions of metals in soil. Bioavailable Contaminant Stripping (BCS) would be a remediation approach focused to remove the bioavailable metal fractions. BCS have been used in a mercury contaminated soil from Italian industrial site. Bioavailable fractions were determined by sequential extraction with H2O and NH4Cl.Combined treatments of plant hormone and thioligand to strength Hg uptake by crop plants (Brassica juncea and Helianthus annuus) were tested. Plant biomass, evapotranspiration, Hg uptake and distribution following treatments were compared. Results indicate the plant hormone, cytokinine (CK) foliar treatment, increased evapotranspiration rate in both tested plants. The Hg uptake and translocation in both tested plants increased with simultaneous addition of CK and TS treatments. B. juncea was the most effective in Hg uptake. Application of CK to plants grown in TS-treated soil lead to an increase in Hg concentration of 232% in shoots and 39% in roots with respect to control. While H. annuus gave a better response in plant biomass production, the application of CK to plants grown in TS-treated soil lead to

Functional Diversity of Fungal Communities in Soil Contaminated with Diesel Oil

Directory of Open Access Journals (Sweden)

Agata Borowik

2017-09-01

Full Text Available The widespread use and consumption of crude oil draws the public’s attention to the fate of petroleum hydrocarbons in the environment, as they can permeate the soil environment in an uncontrollable manner. Contamination of soils with petroleum products, including diesel oil (DO, can cause changes in the microbiological soil properties. The effect of diesel oil on the functional diversity of fungi was tested in a model experiment during 270 days. Fungi were isolated from soil and identified. The functional diversity of fungal communities was also determined. Fungi were identified with the MALDI-TOF method, while the functional diversity was determined using FF-plates made by Biolog®, with 95 carbon sources. Moreover, the diesel oil degradation dynamics was assessed. The research showed that soil contaminated with diesel oil is characterized by a higher activity of oxireductases and a higher number of fungi than soil not exposed to the pressure of this product. The DO pollution has an adverse effect on the diversity of fungal community. This is proved by significantly lower values of the Average Well-Color Development, substrates Richness (R and Shannon–Weaver (H indices at day 270 after contamination. The consequences of DO affecting soil not submitted to remediation are persistent. After 270 days, only 64% of four-ringed, 28% of five-ringed, 21% of 2–3-ringed and 16% of six-ringed PAHs underwent degradation. The lasting effect of DO on communities of fungi led to a decrease in their functional diversity. The assessment of the response of fungi to DO pollution made on the basis of the development of colonies on Petri dishes [Colony Development (CD and Eco-physiological Diversity (EP indices] is consistent with the analysis based on the FF MicroPlate system by Biolog®. Thus, a combination of the FF MicroPlate system by Biolog® with the simultaneous calculation of CD and EP indices alongside the concurrent determination of the content of

Application of autoradiographic methods for contaminant distribution studies in soils

International Nuclear Information System (INIS)

Povetko, O.G.; Higley, K.A.

2000-01-01

In order to determine physical location of contaminants in soil, solidified soil 'thin' sections, which preserve the undisturbed structural characteristics of the original soil, were prepared. This paper describes an application of different autoradiographic methods to identify the distribution of selected nuclides along key structural features of sample soils and sizes of 'hot particles' of contaminant. These autoradiographic methods included contact autoradiography using CR-39 (Homalite Plastics) plastic alpha track detectors and neutron-induced autoradiography that produced fission fragment tracks in Lexan (Thrust Industries, Inc.) plastic detectors. Intact soil samples containing weapons-grade plutonium from Rocky Flats Environmental Test Site and control samples from outside the site location were used in thin soil section preparation. Distribution of particles of actinides was observed and analyzed through the soil section depth profile from the surface to the 15-cm depth. The combination of two autoradiographic methods allowed to distinguish alpha- emitting particles of natural U, 239+240 Pu and non-fissile alpha-emitters. Locations of 990 alpha 'stars' caused by 239+240 Pu and 241 Am 'hot particles' were recorded, particles were sized, their size-frequency, depth and activity distributions were analyzed. Several large colloidal conglomerates of 239+240 Pu and 241 Am 'hot particles' were found in soil profile. Their alpha and fission fragment 'star' images were micro photographed. (author)

Chemical and toxicological characterization of slurry reactor biotreatment of explosives-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Griest, W.H.; Stewart, A.J.; Vass, A.A.; Ho, C.H.

1998-08-01

Treatment of 2,4,6-trinitrotoluene (TNT)-contaminated soil in the Joliet Army Ammunition Plant (JAAP) soil slurry bioreactor (SSBR) eliminated detectable TNT but left trace levels of residual monoamino and diamino metabolites under some reactor operating conditions. The reduction of solvent-extractable bacterial mutagenicity in the TNT-contaminated soil was substantial and was similar to that achieved by static pile composts at the Umatilla Army Depot Activity (UMDA) field demonstration. Aquatic toxicity to Ceriodaphnia dubia from TNT in the leachates of TNT-contaminated soil was eliminated in the leachates of JAAP SSBR product soil. The toxicity of soil product leachates to Ceriodaphnia dubia was reasonably predicted using the specific toxicities of the components detected, weighted by their leachate concentrations. In samples where TNT metabolites were observed in the soil product and its leachates, this method determined that the contribution to predicted toxicity values was dominated by trace amounts of the diamino-metabolites, which are very toxic to ceriodaphnia dubia. When the SSBR operating conditions reduced the concentrations of TNT metabolites in the product soils and their leachates to undetectable concentrations, the main contributors to predicted aquatic toxicity values appeared to be molasses residues, potassium, and bicarbonate. Potassium and bicarbonate are beneficial or benign to the environment, and molasses residues are substantially degraded in the environment. Exotoxins, pathogenic bacteria, inorganic particles, ammonia, and dissolved metals did not appear to be important to soil product toxicity.

Treatment of NORM contaminated soil from the oilfields.

Science.gov (United States)

Abdellah, W M; Al-Masri, M S

2014-03-01

Uncontrolled disposal of oilfield produced water in the surrounding environment could lead to soil contamination by naturally occurring radioactive materials (NORM). Large volumes of soil become highly contaminated with radium isotopes ((226)Ra and (228)Ra). In the present work, laboratory experiments have been conducted to reduce the activity concentration of (226)Ra in soil. Two techniques were used, namely mechanical separation and chemical treatment. Screening of contaminated soil using vibratory sieve shaker was performed to evaluate the feasibility of particle size separation. The fractions obtained were ranged from less than 38 μm to higher than 300 μm. The results show that (226)Ra activity concentrations vary widely from fraction to fraction. On the other hand, leaching of (226)Ra from soil by aqueous solutions (distilled water, mineral acids, alkaline medias and selective solvents) has been performed. In most cases, relatively low concentrations of radium were transferred to solutions, which indicates that only small portions of radium are present on the surface of soil particles (around 4.6%), while most radium located within soil particles; only concentrated nitric acid was most effective where 50% of (226)Ra was removed to aqueous phase. However, mechanical method was found to be easy and effective, taking into account safety procedures to be followed during the implementation of the blending and homogenization. Chemical extraction methods were found to be less effective. The results obtained in this study can be utilized to approach the final option for disposal of NORM contaminated soil in the oilfields. Copyright © 2013 Elsevier Ltd. All rights reserved.

Characterization and inventory of contaminants in WAG 2 floodplain soils of White Oak Creek

International Nuclear Information System (INIS)

Ford, C.J.; Nyquist, J.E.; Purucker, S.T.; Burgoa, B.B.; Winterfield, R.F.

1997-01-01

A remedial investigation was conducted to determine the extent and type of contamination in the floodplain soils of Waste Area Grouping (WAG) 2, in conjunction with environmental restoration activities at the US Department of Energy (DOE) Oak Ridge Reservation (ORR). WAG 2 is located downstream from the main Oak Ridge National Laboratory (ORNL) plant area. As a result of past, present, and potential future releases of hazardous substances to the environment, the ORR was placed on the National Priorities List in December 1989. Sites on this list must be investigated to determine if remedial actions are possible. This report documents the findings of the remedial investigation of the WAG 2 floodplain soils by (1) presenting the characterization and inventory of contaminants, (2) comparing the walkover survey data to quantitative gamma-emitting radionuclide data, and (3) presenting an assessment of human health risk from exposure to these soils. Contaminant characterization results indicated that the primary contaminants in the WAG 2 floodplain are the gamma-emitting radionuclides 137 Cs and 60 Co, although cobalt activity levels are 1/25th or less than those of cesium. Inorganic contaminants discussed in this report were limited to those contributing significantly to human exposure: antimony, barium, chromium(IV), manganese, mercury, and nickel

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.

Analytical Evaluation to Determine Selected PAHs in a Contaminated Soil With Type II Fuel

International Nuclear Information System (INIS)

Garcia Alonso, S.; Perez Pastor, R. M.; Sevillano Castano, M. L.; Garcia Frutos, F. J.

2010-01-01

A study on the optimization of an ultrasonic extraction method for selected PAHs determination in soil contaminated by type II fuel and by using HPLC with fluorescence detector is presented. The main objective was optimize the analytical procedure, minimizing the volume of solvent and analysis time and avoiding possible loss by evaporation. This work was carried out as part of a project that investigated a remediation process of agricultural land affected by an accidental spillage of fuel (Plan Nacional I + D + i, CTM2007-64 537). The paper is structured as: Optimization of wavelengths in the chromatographic conditions to improve resolution in the analysis of fuel samples. Optimization of the main parameters affecting in the extraction process by sonication. Comparison of results with those obtained by accelerated solvent extraction. (Author) 3 refs.

Restoration of contaminated soils; Restauracion de suelos contaminados

Energy Technology Data Exchange (ETDEWEB)

Miranda J, Jose Eduardo

2009-07-01

A great variety of techniques are used for the restoration of contaminated soils. The contamination is present by both organic and inorganic pollutants. Environmental conditions and soil characteristics should take into account in order to implement a remedial technique. The bioremediation technologies are showed as help to remove a variety of soil contaminants. (author) [Spanish] Una gran variedad de tecnicas son utilizadas para la restauracion de suelos contaminados. La contaminacion se presenta tanto por contaminantes organicos como inorganicos. Las condiciones ambientales y caracteristicas del suelo se deben de tomar en cuenta para poder implementar una tecnica remediadora. Las tecnologias de biorremediacion son mostradas como ayuda para remover una gran variedad de contaminantes del suelo. (autor)

Electromigration of Contaminated Soil by Electro-Bioremediation Technique

Science.gov (United States)

Azhar, A. T. S.; Nabila, A. T. A.; Nurshuhaila, M. S.; Shaylinda, M. Z. N.; Azim, M. A. M.

2016-07-01

Soil contamination with heavy metals poses major environmental and human health problems. This problem needs an efficient method and affordable technological solution such as electro-bioremediation technique. The electro-bioremediation technique used in this study is the combination of bacteria and electrokinetic process. The aim of this study is to investigate the effectiveness of Pseudomonas putida bacteria as a biodegradation agent to remediate contaminated soil. 5 kg of kaolin soil was spiked with 5 g of zinc oxide. During this process, the anode reservoir was filled with Pseudomonas putida while the cathode was filled with distilled water for 5 days at 50 V of electrical gradient. The X-Ray Fluorescent (XRF) test indicated that there was a significant reduction of zinc concentration for the soil near the anode with 89% percentage removal. The bacteria count is high near the anode which is 1.3x107 cfu/gww whereas the bacteria count at the middle and near the cathode was 5.0x106 cfu/gww and 8.0x106 cfu/gww respectively. The migration of ions to the opposite charge of electrodes during the electrokinetic process resulted from the reduction of zinc. The results obtained proved that the electro-bioremediation reduced the level of contaminants in the soil sample. Thus, the electro-bioremediation technique has the potential to be used in the treatment of contaminated soil.

Selective flotation for the removal of radionuclides from contaminated soil

International Nuclear Information System (INIS)

Miller, J.D.; Yu, Q.; Lu, Y.Q.

1995-01-01

Low-level radioactive contaminated soils (10--500 pci/gm) created by defense-related activities at certain Superfund sites, such as Nevada Test Site (NTS), is a current environmental concern. Many of these contaminated sites may require appropriate cleanup and restoration, which could cost billions of dollars and put tremendous pressure on limited financial resources. Therefore, the development of a selective flotation process to separate such radionuclides from contaminated soils should be considered. In this study, both a pure depleted UO 2 sample and three synthetic UO 2 /soil mixtures were used to evaluate surface chemistry features and to examine the possibility for the flotation of fine UO 2 particles from selected soils. It was intended that this model system would be a reasonable representation of contaminated soils such as those found the Nevada Test Site which are reported to be contaminated by PuO 2 fallout. The effect of reagent schedule, particle size distribution, and surface charge are discussed with respect to the flotation separation of the UO 2 /soil mixtures. It was found that both commercial fatty acids and reagent grade sodium oleate are effective collectors for UO 2 flotation provided the pH is adjusted to the range of pH 8--9. The bench-scale flotation results successfully demonstrated that froth flotation technology can be used to remove UO 2 from such model contaminated soils with appropriate flotation chemistry conditions which depend on the soil characteristics and other pretreatment procedures

The Effects of Environmental Factors on Biological Remediation of Petroleum Hydrocarbon Contaminated Soil

Directory of Open Access Journals (Sweden)

Mohammad reza Moslemi

2005-09-01

Full Text Available Among the consequences of discharging industrial wastes to land and water bodies, is the widespread accumulation and migration of toxic chemical mixtures in soil and groundwater resources. It is believed that the accumulation of contaminants in the environment constitutes a serious threat to ecological and human health. Bioremediation is an effective measure in dealing with such contaminations particularly those from petroleum hydrocarbon sources; moreover bioremediation is emerging as a promising technology for the treatment of soil and groundwater contamination. Therefore the goal of this study is discussing the theory and practice of biological remediation of petroleum hydrocarbon contaminated soils and assessing the effects of operational conditions and parameters such as: temperature, dissolved oxygen concentration and  pH on the removal rate of the target contaminant which is handled in the designed reactor. Due to large production and consumption rate of diesel fuel inIran and many other countries, diesel fuel has been selected as target contaminant. In this study TOC and COD testing methods have been used to measure and assess the removal rate of the contaminant in the reactor. The experimental results indicate that, considering the operational conditions the indigenous microorganisms which have been separated from the soil are able to remove 50 to 83 percent of the contaminant after 30 days. Thereafter on the base of the results and considering the laboratorial specifications and conditions applied in this project, the optimum values of temperature, dissolved oxygen concentration andpH were respectively determined as 35°C, 4mg/L and 7.

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

SUPERCRITICAL FLUID EXTRACTION OF POLYCYCLIC AROMATIC HYDROCARBON MIXTURES FROM CONTAMINATED SOILS

Science.gov (United States)

Highly contaminated (with PAHs) topsoils were extracted with supercritical CO2 to determine the feasibility and mechanism of supercritical fluid extraction (SFE). Effect of SCF density, temperature, cosolvent type and amount, and of slurrying the soil with water were ...

Assessing soil and groundwater contamination from biofuel spills.

Science.gov (United States)

Chen, Colin S; Shu, Youn-Yuen; Wu, Suh-Huey; Tien, Chien-Jung

2015-03-01

Future modifications of fuels should include evaluation of the proposed constituents for their potential to damage environmental resources such as the subsurface environment. Batch and column experiments were designed to simulate biofuel spills in the subsurface environment and to evaluate the sorption and desorption behavior of target fuel constituents (i.e., monoaromatic and polyaromatic hydrocarbons) in soil. The extent and reversibility of the sorption of aromatic biofuel constituents onto soil were determined. When the ethanol content in ethanol-blended gasoline exceeded 25%, enhanced desorption of the aromatic constituents to water was observed. However, when biodiesel was added to diesel fuel, the sorption of target compounds was not affected. In addition, when the organic carbon content of the soil was higher, the desorption of target compounds into water was lower. The empirical relationships between the organic-carbon normalized sorption coefficient (Koc) and water solubility and between Koc and the octanol-water partition coefficient (Kow) were established. Column experiments were carried out for the comparison of column effluent concentration/mass from biofuel-contaminated soil. The dissolution of target components depended on chemical properties such as the hydrophobicity and total mass of biofuel. This study provides a basis for predicting the fate and transport of hydrophobic organic compounds in the event of a biofuel spill. The spill scenarios generated can assist in the assessment of biofuel-contaminated sites.

Experimental determinations of soil copper toxicity to lettuce (Lactuca sativa) growth in highly different copper spiked and aged soils

DEFF Research Database (Denmark)

Christiansen, Karen Søgaard; Borggaard, Ole K.; Holm, Peter Engelund

2015-01-01

Accurate knowledge about factors and conditions determining copper (Cu) toxicity in soil is needed for predicting plant growth in various Cu-contaminated soils. Therefore, effects of Cu on growth (biomass production) of lettuce (Lactuca sativa) were tested on seven selected, very different soils...

Improving the phytoremediation of heavy metals contaminated soil by use of sewage sludge

Science.gov (United States)

Placek, Agnieszka; Grobelak, Anna; Kacprzak, Malgorzata

2016-01-01

ABSTRACT Sewage sludge, in particular from the food industry, is characterized by fertilizing properties, due to the high content of organic matter and nutrients. The application of sewage sludge causes an improvement of soil parameters as well as increase in cation exchange capacity, and thus stronger binding of cations in the soil environment, which involves the immobilization of nutrients and greater resistance to contamination. In a field experiment sewage sludge has been used as an additive to the soil supporting the phytoremediation process of land contaminated with heavy metals (Cd, Zn, and Pb) using trees species: Scots pine (Pinus silvestris L.), Norway spruce (Picea abies L.), and oak (Quercus robur L.). The aim of the research was to determine how the application of sewage sludge into the soil surface improves the phytoremediation process. The conducted field experiment demonstrated that selected trees like Scots pine and Norway spruce, because of its excellent adaptability, can be used in the remediation of soil. Oak should not be used in the phytoremediation process of soils contaminated with high concentrations of trace elements in the soil, because a significant amount of heavy metals was accumulated in the leaves of oak causing a risk of recontamination. PMID:26368503

Potential and real ecological threat of heavy metals in contaminated soils

Science.gov (United States)

Motuzova, Galina; Barsova, Natalia; Makarichev, Ivan; Karpova, Elena

2013-04-01

Introduction. Microelements or heavy metals (HM) occur in nature and are required for living organisms at low concentrations. High content of HM in soils characterize their potential danger for ecosystem. Their real ecological threat is presented by the mobility of HM in soils. The aim of this work was to characterize the potential and real danger of HM on the basis of HM mobility in soils and their influence of the most important soils properties. Materials and methods. Two types of materials are presented in this paper. The first ones are presented by the summarized information about the content of Cu, Zn, Mn and their mobile species in the soils of Russia and are included into the National Atlas of Russian soils (2011). The second part is presented by the results of laboratory experiments with some samples of Podzols, Podzoluvisol and Chernozem. The following parameters have been determined: a) the main chemical properties of soils; b) the water extracts from soils were investigated by the potentiometric titration with HM salts; c) the properties of the samples of humic acids (HA, extracted by 1n. NaOH) and HA-Cu complexes were determined: molecular-masses distribution (MMD), infrared spectra (IRS), hydrophobility, 1? NMR spectra Results and discussions. The major part of HM in soils of natural landscapes is firmly bound to several minerals. Their threat for living organisms is largely dependent on a relatively higher mobility of HM in soils. The main factors affecting the mobility of HM include soil reaction and sorption processes. In soils of natural landscapes the share of mobile HM compounds is estimated as some per cents from their total content. Having used the data about microelements in soils, their availability to living organisms, 14 natural biogeochemical provinces have been distinguished at the territory of the European part of the former USSR. It permitted to show the adverse impact rendered by microelements at low or high concentrations on living

Leaching of PFC from soils contaminated with PFC of different origin

Science.gov (United States)

Kalbe, Ute; Piechotta, Christian; Rothe, Robert

2017-04-01

Leaching tests are fundamental tools for the assessment of groundwater impact by contaminated soils concerning the soil-groundwater pathway. Such procedures are supposed to serve as the basis for a reliable leachate prognosis. They can be applied to determine the short and long term leaching behaviour as well as the source term of contaminated soils. For this purpose two types of leaching procedures have been validated in Germany for the examination of the leaching behaviour of frequently occurring organic substances (DIN 19528 - column test and DIN 19529 - batch test). A liquid-to-solid ratio (L/S) of 2 L/kg and 10 L/kg) is the basis for the risk assessment which is implemented in different German regulations. The equivalence of test results for both tests for the same material under investigation has been investigated for a variety of pollutants in order to assess their reliability in compliance testing. However, for emerging pollutants there is hardly data available on this issue. Leaching tests on soils contaminated with emerging pollutants such as PFC (Perfluorinated Surfactants) are currently coming more into consideration due to the increasing detection of contaminated sites. Therefore, two soils were investigated in this study from different contamination source (paper sludge containing compost and fire distinguishing foam) using both leaching tests and both liquid-to-solid ratios. The leachability of the various perfluorinated compounds in relation to their content in solid matter was considered. Furthermore the eluate pre-treatment prior analysis (in particular liquid/solid separation step needed for batch tests) has been taken into account. The comparability of the results from batch and column is dependent on the solubility of the various compounds, on the L/S and on the turbidity in the eluates.

Levels of concern for radioactive contaminations in soil according to soil protection standards

International Nuclear Information System (INIS)

Gellermann, R.; Barkowski, D.; Machtolf, M.

2016-01-01

In the paper the question is examined whether the established soil protection standards for carcinogenic substances are also applicable to the assessment of radioactive soil contamination. Referring to the methods applied in soil protection for evaluation of dose-effectrelations and estimations of carcinogenic risks as well as the calculation methods for test values in soil protection ''levels of concern'' for soil contamination by artificial radionuclides are derived. The values obtained are significantly larger than the values for unrestricted clearance of ground according to the German Radiation Protection Ordinance (StrlSchV). The thesis that soil is protected according to environmental standards provided that radiation protection requirements are met needs further checks but can be probably confirmed if the radiation protection requirements are clearly defined.

Determining Arsenic Distribution in Urban Soils: A Comparison with Nonurban Soils

Directory of Open Access Journals (Sweden)

Tait Chirenje

2002-01-01

Full Text Available There are many challenges in the determination of arsenic background concentrations in soils. However, these challenges are magnified when those determinations are carried out on urban soils. Irrespective of this, it is important to correctly identify and understand the extent of pollution in order to provide efficient preventative, remedial actions and cost-effective management of contaminated areas. This review paper discusses the factors that make the determination of arsenic background concentrations in urban areas different from similar determinations in nonurban areas. It also proposes solutions, where applicable, that are based on experience in determining arsenic background concentrations in both urban and nonurban areas in Florida, and from other studies in the literature. Urban soils are considerably different from nonurban areas because they have significant human disturbance, making them more difficult to study. They are characterized by high spatial and temporal variability, compaction, and modified chemical and physical characteristics. These differences have to be addressed during site selection, sample collection, and statistical analyses when determining arsenic distribution.

Enrichment of arbuscular mycorrhizal fungi in a contaminated soil after rehabilitation.

Science.gov (United States)

Lopes Leal, Patrícia; Varón-López, Maryeimy; Gonçalves de Oliveira Prado, Isabelle; Valentim Dos Santos, Jessé; Fonsêca Sousa Soares, Cláudio Roberto; Siqueira, José Oswaldo; de Souza Moreira, Fatima Maria

Spore counts, species composition and richness of arbuscular mycorrhizal fungi, and soil glomalin contents were evaluated in a soil contaminated with Zn, Cu, Cd and Pb after rehabilitation by partial replacement of the contaminated soil with non-contaminated soil, and by Eucalyptus camaldulensis planting with and without Brachiaria decumbens sowing. These rehabilitation procedures were compared with soils from contaminated non-rehabilitated area and non-contaminated adjacent soils. Arbuscular mycorrhizal fungi communities attributes were assessed by direct field sampling, trap culture technique, and by glomalin contents estimate. Arbuscular mycorrhizal fungi was markedly favored by rehabilitation, and a total of 15 arbuscular mycorrhizal fungi morphotypes were detected in the studied area. Species from the Glomus and Acaulospora genera were the most common mycorrhizal fungi. Number of spores was increased by as much as 300-fold, and species richness almost doubled in areas rehabilitated by planting Eucalyptus in rows and sowing B. decumbens in inter-rows. Contents of heavy metals in the soil were negatively correlated with both species richness and glomalin contents. Introduction of B. decumbens together with Eucalyptus causes enrichment of arbuscular mycorrhizal fungi species and a more balanced community of arbuscular mycorrhizal fungi spores in contaminated soil. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

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

Managing long-term polycyclic aromatic hydrocarbon contaminated soils: a risk-based approach.

Science.gov (United States)

Duan, Luchun; Naidu, Ravi; Thavamani, Palanisami; Meaklim, Jean; Megharaj, Mallavarapu

2015-06-01

Polycyclic aromatic hydrocarbons (PAHs) are a family of contaminants that consist of two or more aromatic rings fused together. Soils contaminated with PAHs pose significant risk to human and ecological health. Over the last 50 years, significant research has been directed towards the cleanup of PAH-contaminated soils to background level. However, this achieved only limited success especially with high molecular weight compounds. Notably, during the last 5-10 years, the approach to remediate PAH-contaminated soils has changed considerably. A risk-based prioritization of remediation interventions has become a valuable step in the management of contaminated sites. The hydrophobicity of PAHs underlines that their phase distribution in soil is strongly influenced by factors such as soil properties and ageing of PAHs within the soil. A risk-based approach recognizes that exposure and environmental effects of PAHs are not directly related to the commonly measured total chemical concentration. Thus, a bioavailability-based assessment using a combination of chemical analysis with toxicological assays and nonexhaustive extraction technique would serve as a valuable tool in risk-based approach for remediation of PAH-contaminated soils. In this paper, the fate and availability of PAHs in contaminated soils and their relevance to risk-based management of long-term contaminated soils are reviewed. This review may serve as guidance for the use of site-specific risk-based management methods.

Phytoremediation of Petroleum Hydrocarbon (PHC) Contaminated Soil by Using Mimosa pudica L. .

Science.gov (United States)

Budhadev, Basumatary; Rubul, Saikia; Sabitry, Bordoloi; Hari Prasad, Sarma

2014-07-01

The aim of this study was to evaluate the efficiency of Mimosa pudica L. that could be effective in phytoremediation of PHC-contaminated soil. Experiments were conducted in net house to determine the tolerance of this species to a heavy crude oil contaminated soil under the application of two fertilizer levels and reduction of PHC was monitored for 180 days. Assessment of plant growth, biomass and Total Oil and Grease (TOG) degradation were carried out at an interval of 60 days. In the presence of contaminants, biomass and plant height were reduced up to 27% and 10.4% respectively. Experiments with different percentages of crude oil showed that M. pudica could tolerate crude-oil contamination up to 6.2% (w/w). The estimation of TOG in soil of the tested plants revealed that M. pudica could decrease 31.7% of crude oil contaminants in low fertilizer level (200N, 100P, 100K) and 24.7% in high fertilizer level (240N, 120P, 120K). In case of unplanted pots, the reduction of TOG was 13.7% in low fertilizer level and 11.2% in high fertilizer level. This experiment has identified the suitability of a native candidate plant species for further investigation of their phytoremediation potential.

Soil microbial effects of smelter induced heavy metal contamination

Energy Technology Data Exchange (ETDEWEB)

Nordgren, A

1986-01-01

The soil concentrations of Cu and Zn at the secondary smelter were 20 00 mu g/g dry soil. Close to the primary smelter the soil was contaminated with more than ten elements including Pb, Zn, Cu and As at levels ranging between 6000 and 1000 mu g/g dry soil. The correlations between the concentrations of the metals were high at both smelters. Soil respiration rate decreased by about 75% close to both smelters. Total and fluorescein diacetate stained mycelial lengths decrease with increasing heavy metal pollution at the secondary but not at the primary smelter. The fungal community structure was strongly affected by the contamination. General common in coniferous forest soils such as Penicillium and Oidiodendron virtually vanished, while less frequent species like Paecilomyces farinosus and Geomyces pannorum dominated the site close to the smelter. Colony forming units of a number of functional groups of bacteria were found to be very sensitive to metal contamination. The urease activity of the soil was inhibited. Multivariate statistical analyses showed that the metal contamination was the major environmental influence on the microbiotain the soils studied. A study of about 200 decomposition curves resulting from glutamic acid additions to the different soils produced four microbially related parameters: basal respiration rate, initial respiration rate after the addition of the glutamic acid, specific respiration rate during the exponential increase of the respiration rate and the lag time before the exponential phase. With 53 refs.

Evaluating cadmium bioavailability in contaminated rice paddy soils and assessing potential for contaminant immobilisation with biochar.

Science.gov (United States)

Kosolsaksakul, Peerapat; Oliver, Ian W; Graham, Margaret C

2018-06-01

Cadmium (Cd) contaminated soils from the Mae Sot district in northwest Thailand, a region in which rice Cd concentrations often exceed health limits (0.4 mg/kg) set by the World Health Organisation, were examined for isotopically exchangeable Cd (Cd E values using a 111 Cd spike) to determine how this rates as a predictor of rice grain Cd in comparison with soil total Cd and solution extractable Cd (using the commonly applied BCR scheme and, in an attempt to distinguish carbonate bound forms, the Tessier soil sequential extraction scheme reagents). Step 1 of the BCR scheme (0.11 M CH 3 COOH) and step 1 of the Tessier scheme (1M MgCl 2 ) showed the highest R 2 values in regressions with rice Cd (91% and 90%, respectively), but all predictors were strongly linked to rice Cd (p soil, of the six tested, was an exception to this, where all predictors over-estimated grain Cd by a factor of 2.5-5.7, suggesting that rice grain Cd had been restricted here by the differing flooding regime and subsequent changes to redox conditions. E values and Tessier step 1 extractions were closely related, indicating that these measurements access similar pools of soil Cd. Separately, the isotopic exchangeability (representing bioavailability) of Cd was also assessed in two soils amended with rice husk and miscanthus biochars (0, 1, 5, 10, 15 and 20% w/w) in order to assess the utility of the biochars as a soil amendment for immobilising Cd in situ. One soil showed significant reductions in Cd E value at 5% rice husk biochar addition and at 15% miscanthus biochar addition however, based on the E value-rice grain Cd regression relationship previously established, the E values in the amended soils still predicted for a rice Cd concentration above the health limit. In the second soil, neither of the biochars successfully reduced the Cd E value. This indicates that further work is needed to customise biochar properties to suit specific soil and contaminant situations if they are to be

Amendment trials for bioremediation of sodium and chloride contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Wilson, D. [Western Alfalfa Milling Co. Ltd., Norquay, SK (Canada)

2005-06-30

Details of a soil amendment experiment was presented. Soil samples from sodium and chloride contaminated soil were taken from a site located in southeastern Alberta. Soil amendments included high protein dehydrated alfalfa pellets, 2 types of Zeolite, and used coconut coir. The aim of the study was to find an effective in-situ method of remediating the soil while establishing the highest possible plant biomass. Preliminary trial data indicated a strong trend for high plant protein pellets to increase plant productivity on sodium and chloride contaminated soil. The addition of alfalfa increased plant height and stem diameter, as well as leaf width, which increased incrementally with higher volumes of alfalfa. Equivalent rates of .5 MT to 4 MT per acre application rates were used in the trial. Coconut coir was used at a rate of 30 per cent of the volume of the growing medium and also showed increased growth. An experiment was conducted using harvested plant matter from the samples to determine the effect of the 3 amendments on sodium uptake by the plants. Results showed that the sodium uptake significantly increased with the application of soil amendments, particularly when alfalfa pellets were applied, with percentages of sodium found in the plant tissue almost twice as high as percentages found in the control sample. Sodium levels also increased in the plant tissues where coconut coir was used, although to a lesser degree than levels found in plants grown with the alfalfa amended soils. Zeolite did not perform as well on its own. However, it was noted that previous trials have shown good performance when Zeolite was mixed into sodium/chloride contaminated soils and combined with water filtration. It was concluded that the soil amendments improved plant growth, and increased the sodium uptake by plants. The consortium is pursuing industry support to plan larger field studies in the 2006 season. 2 tabs., 5 figs.

Waste management of actinide contaminated soil

International Nuclear Information System (INIS)

Navratil, J.D.; Thompson, G.H.; Kochen, R.L.

1978-01-01

Waste management processes have been developed to reduce the volume of Rocky Flats soil contaminated with plutonium and americium and to prepare the contaminated fraction for terminal storage. The primary process consists of wet-screening. The secondary process uses attrition scrubbing and wet screening with additives. The tertiary process involves volume reduction of the contaminated fraction by calcination, or fixation by conversion to glass. The results of laboratory scale testing of the processes are described

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.

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

Concept of Aided Phytostabilization of Contaminated Soils in Postindustrial Areas

OpenAIRE

Radziemska, Maja; Koda, Eugeniusz; Bilgin, Ayla; Vaverková, Mgdalena D.

2017-01-01

The experiment was carried out in order to evaluate the effects of trace element immobilizing soil amendments, i.e., chalcedonite, dolomite, halloysite, and diatomite on the chemical characteristics of soil contaminated with Cr and the uptake of metals by plants. The study utilized analysis of variance (ANOVA), principal component analysis (PCA) and Factor Analysis (FA). The content of trace elements in plants, pseudo-total and extracted by 0.01 M CaCl2, were determined using the method of sp...

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

Extractability and bioavailability of Pb and As in historically contaminated orchard soil: Effects of compost amendments

International Nuclear Information System (INIS)

Fleming, Margaret; Tai, Yiping; Zhuang, Ping; McBride, Murray B.

2013-01-01

The availability of Pb and As in an historically contaminated orchard soil, after amendment with compost and aging in the field, was determined by single-step chemical extraction with 1.0 M ammonium acetate at pH 4.8, sequential extraction using the modified BCR test, and a redworm bioassay in the laboratory. The efficiency of soil Pb extraction by ammonium acetate was greater at higher total soil Pb but was reduced by compost amendment. Conversely, the extraction efficiency of total soil As increased with compost amendment, but was not sensitive to total soil As. The redworm bioassay indicated Pb (but not As) bioavailability to be reduced by soil amendment with compost, a result consistent with the ammonium acetate extraction test but not reflected in modified BCR test. Electron microprobe studies of the orchard soil revealed Pb and As to be spatially associated in discrete particles along with phosphorus and iron. -- Highlights: ► Soil Pb and As in an old orchard were concentrated in discrete particles. ► Compost amendment of contaminated soil reduced Pb bioavailability. ► Compost amendment of contaminated soil did not reduce As bioavailability. ► Ammonium acetate extraction test reflected bioavailability of soil Pb and As. -- Remediating metal-contaminated orchard soils with compost reduced lead bioavailability but had little effect on arsenic

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