Volatile Short-chain Chlorinated Hydrocarbons in the Groundwater of the City of Zagreb

OpenAIRE

Marijanović-Rajčić, M.; Senta, A.

2008-01-01

The aim of the study was to assess the quality of the groundwater sampled from private wells and the public water-supply system in terms of estimating the contamination caused by short-chain chlorinated hydrocarbons, as well as to estimate the exposure of the citizens dwelling in different suburbs to these pollutants of their drinking water (Fig. 1). The aim of the study was also to determine which suburb is supplied through the public water-supply system with water originating from the Sašna...

Role of soot in the transport of chlorine in hydrocarbon-air diffusion flames

International Nuclear Information System (INIS)

Venkatesh, S.; Saito, K.; Stencel, J.M.; Majidi, V.; Owens, M.

1991-01-01

Soot is an inevitable product of incomplete combustion in many practical combustion systems such as automobiles, incinerators and furnaces. Recent studies on chlorinated hydrocarbon combustion have shown that soot and other praticulates (eg. fly ash) play an important role in secondary reactions leading to the formation of chlorine substituted polyaromatic hydrocarbons (PAHs). In order to attain very high destruction efficiencies the fundamental chemical and physical processes that are associated with combustion, and post-combustion cleanup must be well understood. In order to understand the effect of chlorine on the soot formed in a combustion system, fundamental studies using a coflow laminar hydrocarbon-air diffusion flame have been carried out. Phenomenological studies have revealed the effect of chlorine on the visible structure of the flame. Soot inception activation energies were estimated for methane, ethane and ethylene diffusion flames for the case of with and without chlorine addition. No significant difference in the activation energy was estimated for either case. The effect of chlorine on the soot escape rate of an acetylene diffusion flame was estimated. The soot formed in these diffusion flames was analyzed for chlorine using scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS) and by laser induced plasma spectroscopy (LIPS). REsults from these techniques indicate the presence of chlorine in the soot formed. In this paper a chemical scheme to explain the chlorine found in the soot is proposed based on known theories of soot formation

Chlorinated hydrocarbons in a pelagic community

International Nuclear Information System (INIS)

Elder, D.; Fowler, S.W.

1976-01-01

For several years data have been accruing on the distribution of chlorinated hydrocarbon pollutants in marine ecosystems. An overall picture of ambient levels in biota, water and sediments is now emerging however, despite the vast amount of data collected to date, questions still arise as to whether certain pollutants such as chlorinated hydrocarbons are indeed magnified through the marine food web. Evidence both for and against trophic concentration of PCB and DDT compounds has been cited. The answer to this question remains unclear due to lack of adequate knowledge on the relative importance of food and water in the uptake of these compounds as well as the fact that conclusions are often confounded by comparing pollutant concentrations in successive links in the food chain sampled at different geographical locations and/or at different points in time. The situation is further complicated by complex prey-predator relationships that exist in many marine communities. In the present study we have tried to eliminate some of these problems by examining PCB and DOT concentrations in species belonging to a relatively well-defined pelagic food chain sampled at one point in space and time

Intrinsic and enhanced bioremediation in aquifers contaminated with chlorinated and aromatic hydrocarbons in The Netherlands

NARCIS (Netherlands)

Rijnaarts, H.H.M.; Aalst-van Leeuwen, M.A. van; Heiningen, E. van; Buyzen, H. van; Sinke, A.; Liere, H.C. van; Harkes, M.; Baartmans, R.; Bosma, T.N.P.; Doddema, H.J.

1998-01-01

The feasibility of intrinsic and enhanced bioremediation approaches for 16 contaminated sites in the Netherlands are discussed. At at least five out of 10 chlorinated solvent sites, natural attenuation can be used as one of the tools to prevent further dispersion of the plume. At two sites

Biotransformation of monoaromatic and chlorinated hydrocarbons at an aviation-gasoline spill site

International Nuclear Information System (INIS)

Wilson, B.H.; Wilson, J.T.; Kampbell, D.H.; Bledsoe, B.E.; Armstrong, J.M.

1991-01-01

Loss of petroleum products from underground storage tanks, pipelines, and accidental spills are major sources of contamination of unsaturated soils, aquifer solids, and a shallow water table aquifer under the U.S. Coast Guard Air Station at Traverse City, MI, has acclimated to the aerobic and anaerobic transformation of monoaromatic hydrocarbons (BTX) released from an aviation gasoline spill. The aquifer also exhibits reductive dechlorination of a chlorinated solvent spill adjacent to the aviation gasoline spill. The groundwater is buffered near neutrality. The aviation gasoline plume is methanogenic and the aquifer contains enough iron minerals to support significant iron solubilization. Field evidence of both aerobic and anaerobic biotransformation of monoaromatics was confirmed by laboratory studies of aquifer material obtained from the site. In the laboratory studies, the removal of the monoaromatics in the anaerobic material was rapid and compared favorable with removal in the aerobic material. The kinetics of anaerobic removal of monoaromatics in the laboratory were similar to the kinetics at field scale in the aquifer. Biotransformation of the chlorinated solvents was not observed until late in the study, when daughter products from reductive dechlorination of the chlorinated solvents were identified by GC/MS

Detecting chlorinated hydrocarbon residues: Rachel Carson's villains.

Science.gov (United States)

Travis, Anthony S

2012-07-01

In 1962, Rachel Carson's Silent Spring drew the public's attention to the deleterious effects of chlorinated hydrocarbons employed as economic poisons in agriculture. However, she did not discuss how their residues could be routinely identified and quantified. In part, this was because the introduction of instruments for use in environmental analysis had only just begun, and she was probably unaware of their existence. The development of the instrumental methods began in industry, particularly at Dow and Shell, in the mid-1950s. Dow scientists, by combining mass spectrometry with gas chromatography, developed the most powerful technique, then and now, for the separation, quantitation and identification of chlorinated hydrocarbons. Shell scientists were no less innovative, particularly with the application of highly sensitive gas chromatography detectors to trace analysis. The first of these detectors, the electron capture detector, was invented by James Lovelock at the National Institute of Medical Research, North London, at the end of the 1950s. Around the same time, Dale Coulson in the USA developed his microcoulometric detector.

In situ sensing of subsurface contamination--part I: near-infrared spectral characterization of alkanes, aromatics, and chlorinated hydrocarbons.

Science.gov (United States)

Klavarioti, Maria; Kostarelos, Konstantinos; Pourjabbar, Anahita; Ghandehari, Masoud

2014-05-01

There is an imperative need for a chemical sensor capable of remote, in situ, long-term monitoring of chemical species at sites containing toxic chemical spills, specifically at chemical waste dumps, landfills, and locations with underground storage tanks. In the current research, a series of experiments were conducted measuring the near-infrared optical absorption of alkanes, aromatics, and chlorinated hydrocarbons. A spectral library was then developed to characterize the optical spectra of liquid hydrocarbons. Near-infrared analysis was chosen due to compatibility with optical fibers. The goal was to differentiate between classes of hydrocarbons and to also discriminate between compounds within a class of similar molecular structures. It was observed that unique absorption spectra can be obtained for each hydrocarbon, and this uniqueness can be used to discriminate between hydrocarbons from different families. Statistical analyses, namely, principal component analysis (PCA) and correlation coefficient (Spearman and Pearson methods), were attempted to match absorption spectra from an unknown hydrocarbon with the database with limited success. An algorithm was subsequently written to identify the characteristic peaks of each hydrocarbon that could be used to match data from an unknown chemical species with the database.

Treatability of volatile chlorinated hydrocarbon-contaminated soils of different textures along a vertical profile by mechanical soil aeration: A laboratory test.

Science.gov (United States)

Ma, Yan; Shi, Yi; Hou, Deyi; Zhang, Xi; Chen, Jiaqi; Wang, Zhifen; Xu, Zhu; Li, Fasheng; Du, Xiaoming

2017-04-01

Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons (VCHs). Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures (silty, clayey, and sandy soils) along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform (TCM) and trichloroethylene (TCE). Mechanical soil aeration was effective for remediating VCHs (removal efficiency >98%). The volatilization process was described by an exponential kinetic function. In the early stage of treatment (0-7hr), rapid contaminant volatilization followed a pseudo-first order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner. Copyright © 2016. Published by Elsevier B.V.

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.

Distribution of nonionic organic compounds (highly volatile chlorinated hydrocarbons) in the unsaturated zone

Energy Technology Data Exchange (ETDEWEB)

Grathwohl, P.

1988-01-01

Nonpolar pollutants, e.g. highly volatile chlorinated hydrocarbons (HVCH) are more or less equally distributed among all three soil phases (solids, water, air) in the unsaturated zone. The sorption of HVCH on soil solids depends on the amount and type of organic matter in the soil. For wet material an additional sorption on mineral surfaces can be neglected, since all possible sites for sorption are occupied by water. Provided the partition-coefficients or sorption-constants are known the contamination of the whole system can be evaluated from the pollutant concentration in the soil air; in addition it is possible to estimate a groundwater risk.

Determination of chlorinated polycyclic aromatic hydrocarbons in water by solid-phase extraction coupled with gas chromatography and mass spectrometry.

Science.gov (United States)

Wang, Xianli; Kang, Haiyan; Wu, Junfeng

2016-05-01

Given the potential risks of chlorinated polycyclic aromatic hydrocarbons, the analysis of their presence in water is very urgent. We have developed a novel procedure for determining chlorinated polycyclic aromatic hydrocarbons in water based on solid-phase extraction coupled with gas chromatography and mass spectrometry. The extraction parameters of solid-phase extraction were optimized in detail. Under the optimal conditions, the proposed method showed wide linear ranges (1.0-1000 ng/L) with correlation coefficients ranging from 0.9952 to 0.9998. The limits of detection and the limits of quantification were in the range of 0.015-0.591 and 0.045-1.502 ng/L, respectively. Recoveries ranged from 82.5 to 102.6% with relative standard deviations below 9.2%. The obtained method was applied successfully to the determination of chlorinated polycyclic aromatic hydrocarbons in real water samples. Most of the chlorinated polycyclic aromatic hydrocarbons were detected and 1-monochloropyrene was predominant in the studied water samples. This is the first report of chlorinated polycyclic aromatic hydrocarbons in water samples in China. The toxic equivalency quotients of chlorinated polycyclic aromatic hydrocarbons in the studied tap water were 9.95 ng the toxic equivalency quotient m(-3) . 9,10-Dichloroanthracene and 1-monochloropyrene accounted for the majority of the total toxic equivalency quotients of chlorinated polycyclic aromatic hydrocarbons in tap water. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chlorinated hydrocarbons and PCBs in field soils, sediments and sewage sludges

International Nuclear Information System (INIS)

Schaaf, H.

1992-01-01

As requested by the Ministry of Agriculture of the FRG, the 'Verband Deutscher Landwirtschaftlicher Untersuchungs- und Forschungsanstalten (VDLUFA)' built up a data collection over chlorinated hydrocarbons and PCBs in field soils, sediments, sewage sludges. Nearly 70.000 samples were collected and statistically evaluated. The results of these investigations will be described. The major constituents of the chlorinated hydrocarbons generally were Lindane, DDT(total) and HCB. In sewage sludges PCBs could be detected in nearly every sample. The contents of PCBs in field soils are smaller than in sewage sludges. Rather 'high contents', greater than 100-200 μg/kg d.m./organic pollutants, were detected only in 2% of the samples. 7 refs., 5 figs., 2 tabs

Atmospheric chlorinated polycyclic aromatic hydrocarbons in East Asia.

Science.gov (United States)

Kakimoto, Kensaku; Nagayoshi, Haruna; Konishi, Yoshimasa; Kajimura, Keiji; Ohura, Takeshi; Hayakawa, Kazuichi; Toriba, Akira

2014-09-01

This study estimates atmospheric concentrations of chlorinated polycyclic aromatic hydrocarbons (ClPAHs) and polycyclic aromatic hydrocarbons (PAHs) in East Asia using a Gas Chromatograph with High Resolution Mass Spectrometer (GC-HRMS). ClPAHs are ubiquitously generated from PAHs through substitution, and some ClPAHs show higher aryl hydrocarbon receptor (AhR)-mediated activities than their parent PAHs. Atmospheric particles were collected using a high-volume air sampler equipped with a quartz-fiber filter. We determined the ClPAH concentrations of atmospheric particles collected in Japan (Sapporo, Sagamihara, Kanazawa, and Kitakyushu), Korea (Busan), and China (Beijing). The concentrations of ClPAHs were highest in the winter Beijing sample, where the total mean concentration was approximately 15-70 times higher than in the winter samples from Japan and Korea. The concentrations of Σ19ClPAHs and Σ9PAHs were significantly correlated in the Kanazawa and the Busan samples. This indicates that within those cities ClPAHs and PAHs share the same origin, implying direct chlorination of parent PAHs. Toxic equivalent concentrations (TEQs) of the total ClPAHs and PAHs were lowest in Kanazawa in the summer, reaching 1.18 and 2610fg-TEQm(-3) respectively, and highest in Beijing in the winter, reaching 627 and 4240000fg-TEQm(-3) respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biological regeneration of carrier material for the adsorption of halogen hydrocarbons in plants for cleaning up contaminated groundwater. Final report

International Nuclear Information System (INIS)

Ressel, K.

1993-06-01

Halogen hydrocarbons and above all chlorinated hydrocarbons are widespread harmful substances in soils and in groundwater. When cleaning up groundwater contamination, the contaminants are brought into the gas phase by strip processes. From the gas phase, the contaminants can be adsorbed on different carrier materials, mostly active carbon. One was searching for ways to regenerate this adsorption material. The mixed culture from a sea sediment most suitable for the decomposition of chlorinated hydrocarbons was optimized regarding its decomposition performance and was later used on the technical scale. In the decomposition experiments on the large technical scale, the cultures were lodged on filling bodies which has a much higher amount of gaps. In this case, an optimum supply of the micro-organisms with oxygen and methane is guaranteed, which is used as co-substrate. No intermediate product was found in a gas chromatography examination. The biologically occupied stage is situated between a desorption column and the active carbon filters, and reduces the load of harmful substances which can no longer be brought into the gas phase by stripping out. This has the advantage that it can be integrated in existing plants and can be adapted to any case of contamination by lodging adapted micro-organisms on it. The basis for each application must be separately researched. (orig.) [de

Subsurface Transport of Hydrocarbon Fuel Additives and a Dense Chlorinated Solvent

National Research Council Canada - National Science Library

Guven, O

1996-01-01

This report provides a description of the work done at Auburn University for the research project 'Subsurface Transport of Hydrocarbon Fuel additives and a Chlorinated Solvent', supported by Armstrong...

Bioremediation of soils containing petroleum hydrocarbons, chlorinated phenols, and polycyclic aromatic hydrocarbons

International Nuclear Information System (INIS)

Seech, A.; Burwell, S.; Marvan, I.

1994-01-01

Bench-scale treatability investigations, pilot-scale and full-scale bioremediation projects were conducted to evaluate Daramend trademark bioremediation of soils containing petroleum hydrocarbons, heavy oils, paraffins, chlorinated phenols and polycyclic aromatic hydrocarbons (PAHs). Bench-scale investigations were conducted using glass microcosms. Pilot-scale and full-scale demonstrations were conducted at industrial sites and included treatment of excavated soils and sediments in on-site cells constructed using synthetic liners and covered by steel/polyethylene structures as well as in-situ treatment. A total of approximately 5,000 tons of soil was treated. The soil treatment included organic soil amendments, specialized tillage/aeration apparatus, and strict control of soil moisture. The amendments are composed of naturally-occurring organic materials prepared to soil-specific particle size distributions, nutrient profiles, and nutrient-release kinetics. Bench-scale work indicated that in refinery soil containing high concentrations of heavy oils, extractable hydrocarbon concentrations could be rapidly reduced to industrial clean-up criteria, and that the hydrocarbons were fully mineralized with release of CO 2

Sustainable treatment of hydrocarbon-contaminated industrial land

OpenAIRE

Cunningham, Colin John

2012-01-01

Land contamination by petroleum hydrocarbons is a widespread and global environmental pollution issue from recovery and refining of crude oil and the ubiquitous use of hydrocarbons in industrial processes and applications. Sustainable treatment of hydrocarbon-contaminated industrial land was considered with reference to seven published works on contaminated railway land including the track ballast, crude oil wastes and contaminated refinery soils. A methodology was developed...

Chemical fingerprinting of hydrocarbon-contamination in soil

DEFF Research Database (Denmark)

Boll, Esther Sørensen; Nejrup, Jens; Jensen, Julie K.

2015-01-01

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...... 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...

Microbial transformation of chlorinated aromatics in sediments

NARCIS (Netherlands)

Beurskens, J.E.M.

1995-01-01

Numerous contaminants like heavy metals, polycyclic aromatic hydrocarbons (PAHs), chlorinated benzenes (CBs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p -dioxins (PCDDs) and polychlorinated furans (PCDFs) are detected in the major rivers in the

Kinetics of aerobic cometabolic biodegradation of chlorinated and brominated aliphatic hydrocarbons: A review.

Science.gov (United States)

Jesus, João; Frascari, Dario; Pozdniakova, Tatiana; Danko, Anthony S

2016-05-15

This review analyses kinetic studies of aerobic cometabolism (AC) of halogenated aliphatic hydrocarbons (HAHs) from 2001-2015 in order to (i) compare the different kinetic models proposed, (ii) analyse the estimated model parameters with a focus on novel HAHs and the identification of general trends, and (iii) identify further research needs. The results of this analysis show that aerobic cometabolism can degrade a wide range of HAHs, including HAHs that were not previously tested such as chlorinated propanes, highly chlorinated ethanes and brominated methanes and ethanes. The degree of chlorine mineralization was very high for the chlorinated HAHs. Bromine mineralization was not determined for studies with brominated aliphatics. The examined research period led to the identification of novel growth substrates of potentially high interest. Decreasing performance of aerobic cometabolism were found with increasing chlorination, indicating the high potential of aerobic cometabolism in the presence of medium- and low-halogenated HAHs. Further research is needed for the AC of brominated aliphatic hydrocarbons, the potential for biofilm aerobic cometabolism processes, HAH-HAH mutual inhibition and the identification of the enzymes responsible for each aerobic cometabolism process. Lastly, some indications for a possible standardization of future kinetic studies of HAH aerobic cometabolism are provided. Copyright © 2016 Elsevier B.V. All rights reserved.

Site-specific probabilistic ecological risk assessment of a volatile chlorinated hydrocarbon-contaminated tidal estuary.

Science.gov (United States)

Hunt, James; Birch, Gavin; Warne, Michael St J

2010-05-01

Groundwater contaminated with volatile chlorinated hydrocarbons (VCHs) was identified as discharging to Penrhyn Estuary, an intertidal embayment of Botany Bay, New South Wales, Australia. A screening-level hazard assessment of surface water in Penrhyn Estuary identified an unacceptable hazard to marine organisms posed by VCHs. Given the limitations of hazard assessments, the present study conducted a higher-tier, quantitative probabilistic risk assessment using the joint probability curve (JPC) method that accounted for variability in exposure and toxicity profiles to quantify risk (delta). Risk was assessed for 24 scenarios, including four areas of the estuary based on three exposure scenarios (low tide, high tide, and both low and high tides) and two toxicity scenarios (chronic no-observed-effect concentrations [NOEC] and 50% effect concentrations [EC50]). Risk (delta) was greater at low tide than at high tide and varied throughout the tidal cycle. Spatial distributions of risk in the estuary were similar using both NOEC and EC50 data. The exposure scenario including data combined from both tides was considered the most accurate representation of the ecological risk in the estuary. When assessing risk using data across both tides, the greatest risk was identified in the Springvale tributary (delta=25%)-closest to the source area-followed by the inner estuary (delta=4%) and the Floodvale tributary (delta=2%), with the lowest risk in the outer estuary (delta=0.1%), farthest from the source area. Going from the screening level ecological risk assessment (ERA) to the probabilistic ERA changed the risk from unacceptable to acceptable in 50% of exposure scenarios in two of the four areas within the estuary. The probabilistic ERA provided a more realistic assessment of risk than the screening-level hazard assessment. Copyright (c) 2010 SETAC.

Modeling Catalytic Destruction of Subsurface Contaminants in Recirculating Wells

National Research Council Canada - National Science Library

Cadena, Kerry

2003-01-01

... (National Research Council, 1994). Examples of groundwater contaminants of special interest to DoD and AF installations include fuel hydrocarbons, chlorinated hydrocarbons, and nitroaromatic compounds...

Direct immunofluorescence and enzyme-linked immunosorbent assays for evaluating chlorinated hydrocarbon degrading bacteria

Energy Technology Data Exchange (ETDEWEB)

Brigmon, R.L.; Franck, M.M.; Brey, J.; Fliermans, C.B. [Westinghouse Savannah River, Aiken, SC (United States). Environmental Biotechnology Section; Scott, D.; Lanclos, K. [Medical Coll. of Georgia, Augusta, GA (United States)

1997-06-01

Immunological procedures were developed to enumerate chlorinated hydrocarbon degrading bacteria. Polyclonal antibodies (Pabs) were produced by immunizing New Zealand white rabbits against 18 contaminant-degrading bacteria. These included methanotrophic and chlorobenzene (CB) degrading species. An enzyme-linked immunosorbent assay (ELISA) was used to test for specificity and sensitivity of the Pabs. Direct fluorescent antibodies (DFAs) were developed with these Pabs against select methanotrophic bacteria isolated from a trichloroethylene (TCE) contaminated landfill at the Savannah River Site (SRS) and cultures from the American Type Culture Collection (ATCC). Analysis of cross reactivity testing data showed some of the Pabs to be group specific while others were species specific. The threshold of sensitivity for the ELISA is 105 bacteria cells/ml. The DFA can detect as few as one bacterium per ml after concentration. Results from the DFA and ELISA techniques for enumeration of methanotrophic bacteria in groundwater were higher but not significantly different (P < 0.05) compared to indirect microbiological techniques such as MPN. These methods provide useful information on in situ community structure and function for bioremediation applications within 1--4 hours of sampling.

Bioremediation of Petroleum Hydrocarbon Contaminated Sites

Energy Technology Data Exchange (ETDEWEB)

Fallgren, Paul

2009-03-30

Bioremediation has been widely applied in the restoration of petroleum hydrocarbon-contaminated. Parameters that may affect the rate and efficiency of biodegradation include temperature, moisture, salinity, nutrient availability, microbial species, and type and concentration of contaminants. Other factors can also affect the success of the bioremediation treatment of contaminants, such as climatic conditions, soil type, soil permeability, contaminant distribution and concentration, and drainage. Western Research Institute in conjunction with TechLink Environmental, Inc. and the U.S. Department of Energy conducted laboratory studies to evaluate major parameters that contribute to the bioremediation of petroleum-contaminated drill cuttings using land farming and to develop a biotreatment cell to expedite biodegradation of hydrocarbons. Physical characteristics such as soil texture, hydraulic conductivity, and water retention were determined for the petroleum hydrocarbon contaminated soil. Soil texture was determined to be loamy sand to sand, and high hydraulic conductivity and low water retention was observed. Temperature appeared to have the greatest influence on biodegradation rates where high temperatures (>50 C) favored biodegradation. High nitrogen content in the form of ammonium enhanced biodegradation as well did the presence of water near field water holding capacity. Urea was not a good source of nitrogen and has detrimental effects for bioremediation for this site soil. Artificial sea water had little effect on biodegradation rates, but biodegradation rates decreased after increasing the concentrations of salts. Biotreatment cell (biocell) tests demonstrated hydrocarbon biodegradation can be enhanced substantially when utilizing a leachate recirculation design where a 72% reduction of hydrocarbon concentration was observed with a 72-h period at a treatment temperature of 50 C. Overall, this study demonstrates the investigation of the effects of

Microbial transformation of chlorinated aromatics in sediments

OpenAIRE

Beurskens, J.E.M.

1995-01-01

Numerous contaminants like heavy metals, polycyclic aromatic hydrocarbons (PAHs), chlorinated benzenes (CBs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p -dioxins (PCDDs) and polychlorinated furans (PCDFs) are detected in the major rivers in the Netherlands. These contaminants have relatively low aqueous solubilities and bind substantially to the suspended solids in river water. Due to decreasing stream velocities in the downstream stretches of a...

Electrokinetic-enhanced bioaugmentation for remediation of chlorinated solvents contaminated clay

International Nuclear Information System (INIS)

Mao, Xuhui; Wang, James; Ciblak, Ali; Cox, Evan E.; Riis, Charlotte; Terkelsen, Mads; Gent, David B.; Alshawabkeh, Akram N.

2012-01-01

Highlights: ► Simultaneous delivery of electron donors and bacteria into low permeability clays. ► Bacteria injection, growth and consequent transformation of contaminants are viable. ► EK injection is more effective than advection-based injection for clay soil. ► Electroosmosis appears to be the driving mechanism for bacteria injection. ► Both EK transport and biodegradation contribute the removal of VOCs in clay. - Abstract: Successful bioremediation of contaminated soils is controlled by the ability to deliver bioremediation additives, such as bacteria and/or nutrients, to the contaminated zone. Because hydraulic advection is not practical for delivery in clays, electrokinetic (EK) injection is an alternative for efficient and uniform delivery of bioremediation additive into low-permeability soil and heterogeneous deposits. EK-enhanced bioaugmentation for remediation of clays contaminated with chlorinated solvents is evaluated. Dehalococcoides (Dhc) bacterial strain and lactate ions are uniformly injected in contaminated clay and complete dechlorination of chlorinated ethene is observed in laboratory experiments. The injected bacteria can survive, grow, and promote effective dechlorination under EK conditions and after EK application. The distribution of Dhc within the clay suggests that electrokinetic transport of Dhc is primarily driven by electroosmosis. In addition to biodegradation due to bioaugmentation of Dhc, an EK-driven transport of chlorinated ethenes is observed in the clay, which accelerates cleanup of chlorinated ethenes from the anode side. Compared with conventional advection-based delivery, EK injection is significantly more effective for establishing microbial reductive dechlorination capacity in low-permeability soils.

Bioremediation of chlorinated solvents and diesel soils

International Nuclear Information System (INIS)

Huismann, S.S.; Peterson, M.A.; Jardine, R.J.

1995-01-01

The US Army, in a cooperative effort with the Tennessee Valley Authority (TVA) and its cooperator, ENSR, performed an innovative enhanced bioremediation project at Fort Gillem in Atlanta, Georgia. The objective of the project was to remediate six hundred cubic yards of soil affected by a mixture of chlorinated compounds and petroleum hydrocarbons which posed a threat to uppermost groundwater and private drinking water wells. ENSR completed a demonstration project to measure the effects of bioremediation on both chlorinated compounds (primarily TCE) and petroleum hydrocarbons (number-sign 2 diesel). Contaminated soil was placed on top of a bermed polyethylene liner to construct an ex-situ biovault. Nutrients were added to the soil as it was loaded onto the liner. Contaminated soil was also used to construct a control vault. A methane barrier cover was placed over both piles. The cover was designed to prevent short circuiting of induced airflow in and around the enhanced pile, and to prevent the release of fugitive emissions from either pile

Bench scale studies: Ozonation as a potential treatment for waters contaminated with hydrocarbons or dioxins and furans

International Nuclear Information System (INIS)

Schaal, W.

1995-01-01

The objective of the bench scale studies was to examine the destruction efficiency and efficacy of ozone on chemicals of concern (COC's) commonly found in contaminated ground water and rhenoformer wash water. The ground water used in these tests contained aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits. The rhenoformer wash water used in these tests contained a variety of dioxins (including 2,3,7,8-tetrachlorodibenzo-p-dioxin) and furans. Summaries are presented of the bench scale studies by describing the COCs, methodologies, test reactors, observations, and results. The summaries also detail which applications hold promise with respect to ozonation and which ones do not. Bench test results for the experiments in which aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits where the COCs were relatively successful. Concentrations for the COCs ranging from 300 to 3,400 micrograms per liter (microg/L) were brought below levels specified for storm sewer discharge per the National Priority Discharge Elimination Systems (NPDES) permit requirements. Bench test results for the experiments in which dioxins and furans were the COCs were less promising and revealed that additional processes would have to be used in conjunction with ozonation to bring the concentration of COCs within the targeted ranges. It was realized, however, that the effectiveness and efficacy of ozonation were diminished by the presence of particulates, to which some of the dioxin and furan compounds adhered

Process for in-situ biodegradation of hydrocarbon contaminated soil

International Nuclear Information System (INIS)

Ely, D.L.; Heffner, D.A.

1991-01-01

This patent describes an in situ process for biodegrading hydrocarbons by drawing oxygen into an undisturbed hydrocarbon contaminated zone in a fluid permeable soil. It comprises: establishing a borehole extending from the earth's surface through a hydrocarbon contaminated zone having hydrocarbon degrading microbes therein; lining the borehole with a fluid impermeable liner coaxially spaced and sealingly connected to the inside surface of the borehole and extending from the earth's surface to the hydrocarbon-contaminated zone; the liner including a fluid permeable portion extending from the lower end thereof and through at least a portion of the hydrocarbon contaminated zone, fluidly connecting a source of negative pressure to the fluid impermeable line; evacuating gas from the borehole through the fluid permeable portion of the liner at a rate sufficient to draw air from the earth's surface into the hydrocarbon containing zone; and adjusting the flow rate of the evacuated gas so that the amount of hydrocarbon biodegradation therein is within 50% of the maximum hydrocarbon biodegradation rate as detected by the volume of carbon dioxide in the evacuated gas

WHIM-3D-QSPR APPROACH FOR PREDICTING AQUEOUS SOLUBILITY OF CHLORINATED HYDROCARBONS

Directory of Open Access Journals (Sweden)

Oman Zuas

2010-06-01

Full Text Available The weighted holistic invariant molecular-three dimensional-quantitative structure property relationship (WHIM-3D-QSPR approach has been applied to the study of the aqueous solubility (- log Sw of chlorinated hydrocarbon compounds (CHC's. The obtained QSPR model is predictive and only requires four WHIM-3D descriptors in the calculation. The correlation equation of the model that is based on a training set of 50 CHC's compound has statistical parameters: standard coefficient correlation (R2 = 0.948; cross-validated correlation coefficients (Q2 = 0.935; Standard Error of Validation (SEV = 0.35; and average absolute error (AAE = 0.31. The application of the best model to a testing set of 50 CHC's demonstrates a reliable result with good predictability. Besides, it was possible to construct new model by applying WHIM-3D-QSPR approach without require any experimental physicochemical properties in the calculation of aqueous solubility.   Keywords: WHIM-3D; QSPR; aqueous solubility; - Log Sw, chlorinated hydrocarbons, CHC's

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

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.

Bioremediation in soil contaminated with hydrocarbons in Colombia.

OpenAIRE

María Alejandra Trujillo Toro; Juan Fernando Ramírez Quirama

2012-01-01

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 cont...

Enhancement of in situ Remediation of Hydrocarbon Contaminated Soil

Energy Technology Data Exchange (ETDEWEB)

Palmroth, M.

2006-07-01

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

Modeling Groundwater-Surface Water Interaction and Contaminant Transport of Chlorinated Solvent Contaminated Site

Science.gov (United States)

Yimer Ebrahim, Girma; Jonoski, Andreja; van Griensven, Ann; Dujardin, Juliette; Baetelaan, Okke; Bronders, Jan

2010-05-01

Chlorinated-solvent form one of the largest groups of environmental chemicals. Their use and misuse in industry have lead to a large entry of these chemicals into the environment, resulting in widespread dissemination and oftentimes environmental contamination. Chlorinated solvent contamination of groundwater resources has been widely reported. For instance, there has been much interest in the assessment of these contaminant levels and their evolutions with time in the groundwater body below the Vilvoorde-Machelen industrial area (Belgium). The long industrial history of the area has lead to complex patterns of pollution from multiple sources and the site has been polluted to the extent that individual plumes are not definable any more. Understanding of groundwater/surface water interaction is a critical component for determining the fate of contaminant both in streams and ground water due to the fact that groundwater and surface water are in continuous dynamic interaction in the hydrologic cycle. The interaction has practical consequences in the quantity and quality of water in either system in the sense that depletion and/or contamination of one of the system will eventually affect the other one. The transition zone between a stream and its adjacent aquifer referred to as the hyporheic zone plays a critical role in governing contaminant exchange and transformation during water exchange between the two water bodies. The hyporheic zone of Zenne River ( the main receptor ) is further complicated due to the fact that the river banks are artificially trained with sheet piles along its reach extending some 12 m below the surface. This study demonstrates the use of MODFLOW, a widely used modular three-dimensional block-centred finite difference, saturated flow model for simulating the flow and direction of movement of groundwater through aquifer and stream-aquifer interaction and the use of transport model RT3D, a three-dimensional multi-species reactive transport model

Differentiation of naturally-occurring vs. artificial hydrocarbons in a landfill groundwater investigation

International Nuclear Information System (INIS)

Beaver, J.L.; Hartness, J.A.; Breeding, L.B.; Buchanan, D.M.

1994-01-01

Interpretation of groundwater sampling data at a large municipal/industrial landfill indicates contamination by both artificial and naturally-occurring hydrocarbons. Site hydrogeology consists of three different water bearing zones. The uppermost (shallow) aquifer is an unconfined unit consisting of silt, clay, and sand deposits. An intermediate depth semiconfined aquifer underlies the unconfined unit, and consists of a chert rubble zone and the upper portion of a fractured and solution-enhanced limestone formation. A regionally-extensive organic-rich shale underlies the semiconfined aquifer and separates it from the deep confined aquifer, which also consists of limestone. Groundwater investigations at the landfill have detected chlorinated and non-chlorinated hydrocarbons in the different aquifer intervals. Chlorinated hydrocarbons detected include tetrachloroethene, dichloroethene, and vinyl chloride and occur almost exclusively in the shallow aquifer. Aromatic hydrocarbons detected include benzene, toluene, ethylbenzene, and xylene (BTEX) and-occur in the intermediate and deep aquifers. The landfill was originally interpreted as the source of the contaminants. The observation of free-phase liquid hydrocarbons in the intermediate aquifer at the site, and high dissolved BTEX levels in the deep and intermediate aquifers upgradient of the landfill suggest that the aromatics were derived from a source other than the landfill. A potential source of BTEX contamination may be abandoned (pre-1930) natural gas wells located near the landfill. An additional BTEX source may be the organic-rich shale formation (a documented petroleum source rock)

Assessing impediments to hydrocarbon biodegradation in weathered contaminated soils.

Science.gov (United States)

Adetutu, Eric; Weber, John; Aleer, Sam; Dandie, Catherine E; Aburto-Medina, Arturo; Ball, Andrew S; Juhasz, Albert L

2013-10-15

In this study, impediments to hydrocarbon biodegradation in contaminated soils were assessed using chemical and molecular methodologies. Two long-term hydrocarbon contaminated soils were utilised which were similar in physico-chemical properties but differed in the extent of hydrocarbon (C10-C40) contamination (S1: 16.5 g kg(-1); S2: 68.9 g kg(-1)). Under enhanced natural attenuation (ENA) conditions, hydrocarbon biodegradation was observed in S1 microcosms (26.4% reduction in C10-C40 hydrocarbons), however, ENA was unable to stimulate degradation in S2. Although eubacterial communities (PCR-DGGE analysis) were similar for both soils, the alkB bacterial community was less diverse in S2 presumably due to impacts associated with elevated hydrocarbons. When hydrocarbon bioaccessibility was assessed using HP-β-CD extraction, large residual concentrations remained in the soil following the extraction procedure. However, when linear regression models were used to predict the endpoints of hydrocarbon degradation, there was no significant difference (P>0.05) between HP-β-CD predicted and microcosm measured biodegradation endpoints. This data suggested that the lack of hydrocarbon degradation in S2 resulted primarily from limited hydrocarbon bioavailability. Copyright © 2013 Elsevier B.V. All rights reserved.

Geophysical Responses of Hydrocarbon-impacted Zones at the Various Contamination Conditions

Science.gov (United States)

Kim, C.; Ko, K.; Son, J.; Kim, J.

2008-12-01

One controlled experiment and two field surveys were conducted to investigate the geoelectrical responses of hydrocarbon-contaminated zones, so called smeared zone, on the geophysical data at the hydrocarbon- contaminated sites with various conditions. One controlled physical model experiment with GPR using fresh gasoline and two different 3-D electrical resistivity investigations at the aged sites. One field site (former military facilities for arms maintenance) was mainly contaminated with lubricating oils and the other (former gas station) was contaminated with gasoline and diesel, respectively. The results from the physical model experiment show that GPR signals were enhanced when LNAPL was present as a residual saturation in the water-saturated system due to less attenuation of the electromagnetic energy through the soil medium of the hydrocarbon-impacted zone (no biodegradation), compared to when the medium was saturated with only water (no hydrocarbon impaction). In the former gas station site, 3-D resistivity results demonstrate that the highly contaminated zones were imaged with low resistivity anomalies since the biodegradation of petroleum hydrocarbons has been undergone for many years, causing the drastic increase in the TDS at the hydrocarbon-impacted zones. Finally, 3-D resistivity data obtained from the former military maintenance site show that the hydrocarbon-contaminated zones show high resistivity anomalies since the hydrocarbons such as lubricating oils at the contaminated soils were not greatly influenced by microbial degradation and has relatively well kept their original physical properties of high electrical resistivity. The results of the study illustrated that the hydrocarbon-impacted zones under various contamination conditions yielded various geophysical responses which include (1) enhanced GPR amplitudes at the fresh LNAPL (Gasoline to middle distillates) spill sites, (2) low electrical resistivity anomalies due to biodegradation at the

Evidence for Perchlorates and the Origin of Chlorinated Hydrocarbons Detected by SAM at the Rocknest Aeolian Deposit in Gale Crater

Science.gov (United States)

Glavin, Daniel P.; Freissinet, Caroline; Miller, Kristen E.; Eigenbrode, Jennifer L.; Brunner, Anna E.; Buch, Arnaud; Sutter, Brad; Archer, P. Douglas, Jr.; Atreya, Sushil K.; Brinckerhoff, William B.;

Distribution of petroleum hydrocarbons and organochlorinated contaminants in marine biota and coastal sediments from the ROPME Sea Area during 2005.

Science.gov (United States)

de Mora, Stephen; Tolosa, Imma; Fowler, Scott W; Villeneuve, Jean-Pierre; Cassi, Roberto; Cattini, Chantal

2010-12-01

The composition and spatial distribution of various petroleum hydrocarbons (PHs), comprising both aliphatic and polycyclic aromatic hydrocarbons (PAHs), and selected chlorinated pesticides and PCBs were measured in biota and coastal sediments from seven countries in the Persian Gulf and the Gulf of Oman (Bahrain, Iran, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates). Evidence of extensive marine contamination with respect to organochlorinated compounds and PHs was not observed. Only one site, namely the BAPCO oil refinery in Bahrain, was considered to be chronically contaminated. Comparison of the results from this survey for Σ DDTs and Σ PCBs in rock oysters from the Gulf of Oman with similar measurements made at the same locations over the past two decades indicates a temporal trend of overall decreasing Σ PCB concentrations in oysters, whereas Σ DDTs levels have little changed during that period. Copyright © 2010 Elsevier Ltd. All rights reserved.

Push-Pull Tests for Evaluating the Aerobic Cometabolism of Chlorinated Aliphatic Hydrocarbons

National Research Council Canada - National Science Library

Semprini, Lew

2006-01-01

.... This report describes a newly developed single-well technology for evaluating the feasibility of using in situ aerobic cometabolic processes to treat groundwater contaminated with chlorinated solvent mixtures...

Desorption and bioremediation of hydrocarbon contaminated soils

International Nuclear Information System (INIS)

Gray, M.R.

1998-01-01

A study was conducted in which the extent and pattern of contaminant biodegradation during bioremediation of four industrially-contaminated soils were examined to determine which factors control the ultimate extent of biodegradation and which limit the success of biological treatment. It was noted that although bioremediation is inexpensive and has low environmental impact, it often fails to completely remove the hydrocarbons in soils because of the complex interactions between contaminants, the soil environment, and the active microorganisms. In this study, the competency of the microorganisms in the soil to degrade the contaminants was examined. The equilibrium partitioning of the contaminants between the soil and the aqueous phase was also examined along with the transport of contaminants out of soil particles. The role of diffusion of compounds in the soil and the importance of direct contact between microorganisms and the hydrocarbons was determined. Methods for selecting suitable sites for biological treatment were also described

Geophysical Signitures From Hydrocarbon Contaminated Aquifers

Science.gov (United States)

Abbas, M.; Jardani, A.

2015-12-01

The task of delineating the contamination plumes as well as studying their impact on the soil and groundwater biogeochemical properties is needed to support the remediation efforts and plans. Geophysical methods including electrical resistivity tomography (ERT), induced polarization (IP), ground penetrating radar (GPR), and self-potential (SP) have been previously used to characterize contaminant plumes and investigate their impact on soil and groundwater properties (Atekwana et al., 2002, 2004; Benson et al., 1997; Campbell et al., 1996; Cassidy et al., 2001; Revil et al., 2003; Werkema et al., 2000). Our objective was to: estimate the hydrocarbon contamination extent in a contaminated site in northern France, and to adverse the effects of the oil spill on the groundwater properties. We aim to find a good combination of non-intrusive and low cost methods which we can use to follow the bio-remediation process, which is planned to proceed next year. We used four geophysical methods including electrical resistivity tomography, IP, GPR, and SP. The geophysical data was compared to geochemical ones obtained from 30 boreholes installed in the site during the geophysical surveys. Our results have shown: low electrical resistivity values; high chargeability values; negative SP anomalies; and attenuated GPR reflections coincident with groundwater contamination. Laboratory and field geochemical measurements have demonstrated increased groundwater electrical conductivity and increased microbial activity associated with hydrocarbon contamination of groundwater. Our study results support the conductive model suggested by studies such as Sauck (2000) and Atekwana et al., (2004), who suggest that biological alterations of hydrocarbon contamination can substantially modify the chemical and physical properties of the subsurface, producing a dramatic shift in the geo-electrical signature from resistive to conductive. The next stage of the research will include time lapse borehole

Kinetics of Chlorinated Hydrocarbon Degradation by Methylosinus trichosporium OB3b and Toxicity of Trichloroethylene

NARCIS (Netherlands)

Oldenhuis, Roelof; Oedzes, Johannes Y.; Waarde, Jacob J. van der; Janssen, Dick B.

The kinetics of the degradation of trichloroethylene (TCE) and seven other chlorinated aliphatic hydrocarbons by Methylosinus trichosporium OB3b were studied. All experiments were performed with cells grown under copper stress and thus expressing soluble methane monooxygenase. Compounds that were

The use of DNA technologies in determining the biotreatability of chlorinated aliphatic hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Douglas, A. [HydroQual, Calgary, AB (Canada)

2008-07-01

HydroQual Laboratories is a wholly-owned subsidiary of Golder Associates and uses biological testing for measuring the effect of toxins and their impact on various links in the food chain in order to evaluate and improve environmental health. It has expertise in various fields of the natural sciences and is ISO certified. This presentation discussed the use of DNA technologies in determining the biotreatability of chlorinated aliphatic hydrocarbons. The paper presented biotreatability studies run by the company which included bench scale testing on various types of contaminants. The testing involved multiple treatments, determination of dosage, and additional amendments. The strategy may vary based on bench test results and legislation. Trichloroethylene/perchloroethylene remediation strategies were also presented for chemical oxidation; aerobic bioremediation; abiotic remediation; and anaerobic biostimulation and augmentation. Biostimulation was defined as the addition of nutrients to influence the redox potential. The presentation also reviewed anaerobic dehalorespiration; detection methods; DNA isolation; polymerase chain reaction (PCR); and biotreatability case studies. The presentation concluded with some future directions and other uses of PCR. tabs., figs.

Contaminant risks from biosolids land application Contemporary organic contaminant levels in digested sewage sludge from five treatment plants in Greater Vancouver, British Columbia

International Nuclear Information System (INIS)

Bright, D.A.; Healey, N.

2003-01-01

The risks of organic contaminants in sewage sludges are evaluated. - This study examines the potential for environmental risks due to organic contaminants at sewage sludge application sites, and documents metals and various potential organic contaminants (volatile organics, chlorinated pesticides, PCBs, dioxins/furans, extractable petroleum hydrocarbons, PAHs, phenols, and others) in current production biosolids from five wastewater treatment plants (WWTPs) within the Greater Vancouver Regional District (GVRD). There has been greater focus in Europe, North America and elsewhere on metals accumulation in biosolids-amended soil than on organic substances, with the exception of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans. Another objective, therefore, was to evaluate the extent to which management of biosolids re-use based on metal/metalloid levels coincidentally minimizes environmental risks from organic contaminants. Historical-use contaminants such as chlorophenols, PCBs, and chlorinated pesticides were not detected at environmentally relevant concentrations in any of the 36 fresh biosolids samples, and appear to have virtually eliminated from sanitary collection system inputs. The few organic contaminants found in freshly produced biosolids samples that exhibited high concentrations relative to British Columbia and Canadian soil quality benchmarks included p-cresol, phenol, phenanthrene, pyrene, naphthalene, and heavy extractable petroleum hydrocarbons (HEPHs-nCl9-C34 effective carbon chain length). It was concluded that, with the exception of these petroleum hydrocarbon constituents or their microbial metabolites, the mixing of biosolids with uncontaminated soils during land application and based on the known metal concentrations in biosolids from the Greater Vancouver WWTPs investigated provides adequate protection against the environmental risks associated with organic substances such as dioxins and furans, phthalate esters, or volatile

Radiation induced dechlorination of some chlorinated hydrocarbons in aqueous suspensions of various solid particles

Czech Academy of Sciences Publication Activity Database

Múčka, V.; Buňata, M.; Čuba, V.; Silber, R.; Juha, Libor

2015-01-01

Roč. 112, Jul (2015), s. 108-116 ISSN 0969-806X R&D Projects: GA ČR GA13-28721S Institutional support: RVO:68378271 Keywords : chlorinated hydrocarbons * TCE * PCE * PCBs * dechlorination * gamma irradiation * modifiers * cell membrane permeability Subject RIV: CH - Nuclear ; Quantum Chemistry Impact factor: 1.207, year: 2015

In situ remediation of chlorinated solvent-contaminated groundwater using ZVI/organic carbon amendment in China: field pilot test and full-scale application.

Science.gov (United States)

Yang, Jie; Meng, Liang; Guo, Lin

2018-02-01

Chlorinated solvents in groundwater pose threats to human health and the environment due to their carcinogenesis and bioaccumulation. These problems are often more severe in developing countries such as China. Thus, methods for chlorinated solvent-contaminated groundwater remediation are urgently needed. This study presents a technique of in situ remediation via the direct-push amendment injection that enhances the reductive dechlorination of chlorinated solvents in groundwater in the low-permeability aquifer. A field-based pilot test and a following real-world, full-scale application were conducted at an active manufacturing facility in Shanghai, China. The chlorinated solvents found at the clay till site included 1,1,1-trichloroethane (1,1,1-TCA), 1,1-dichloroethane (1,1-DCA), 1,1-dichloroethylene (1,1-DCE), vinyl chloride (VC), and chloroethane (CA). A commercially available amendment (EHC ® , Peroxychem, Philadelphia, PA) combining zero-valent iron and organic carbon was used to treat the above pollutants. Pilot test results showed that direct-push EHC injection efficiently facilitated the in situ reductive remediation of groundwater contaminated with chlorinated solvents. The mean removal rates of 1,1,1-TCA, 1,1-DCA, and 1,1-DCE at 270 days post-injection were 99.6, 99.3, and 73.3%, respectively, which were obviously higher than those of VC and CA (42.3 and 37.1%, respectively). Clear decreases in oxidation-reduction potential and dissolved oxygen concentration, and increases in Fe 2+ and total organic carbon concentration, were also observed during the monitoring period. These indicate that EHC promotes the anaerobic degradation of chlorinated hydrocarbons primarily via long-term biological reductive dechlorination, with instant chemical reductive dechlorination acting as a secondary pathway. The optimal effective time of EHC injection was 0-90 days, and its radius of influence was 1.5 m. In full-scale application, the maximum concentrations of 1,1,1-TCA

Adsorption of chlorinated hydrocarbons from aqueous solutions by wetted and non-wetted synthetic sorbents:dynamics

NARCIS (Netherlands)

Rexwinkel, G.; Rexwinkel, Glenn; Berkhout, J.T.A.M.; Heesink, Albertus B.M.

2003-01-01

In the present investigation the dynamics of the adsorption of several chlorinated hydrocarbons onto wetted and non-wetted synthetic sorbents was studied. A single particle model was developed to describe the adsorption behavior. The values of the mass transfer coefficient, needed to describe the

Phytoremediation of hydrocarbon-contaminated soil using plants adapted to western Canadian climate

International Nuclear Information System (INIS)

Robson, D.B.

2003-01-01

Phytoremediation relies on the use of plants for in-situ treatment of hydrocarbon contaminated soils. It is based on relationships between plants, microorganisms and the environment. The advantages of the process are its low cost and minimal soil disturbance. Phytoremediation has not been widely implemented in Canada because only a few native or non-native plant species have been tested for hydrocarbon tolerance or degradation ability. More studies are needed to fully understand why some plants are more tolerant of hydrocarbons than others, and whether tolerant species increase hydrocarbon degradation. In this study, several field and growth chamber experiments were conducted to examine hydrocarbon tolerance in plants. Hydrocarbon contaminated field plots had higher soil pH, carbon to nitrogen ratio and bare ground, lower total nitrogen, available phosphorous and litter cover. The mean diversity at the uncontaminated sites was 0.52. It was 0.45 at the contaminated sites. Mean species similarity between contaminated and uncontaminated sites was 31.1 per cent and cover similarity was 22.2 per cent. The common plants in the contaminated field included kochia, wild barley, salt grass, bluegrass, and wheatgrass. The plants that formed most plant cover on contaminated plots were non-mycorrhizal, self-pollinating, and large seeded. The species with the highest survival after 5 weeks in hydrocarbon contaminated soils included one native and 4 non-native grasses, 2 native and 3 non-native legumes and 2 native forbs. All plants (with the exception of Indian breadroot) grown in hydrocarbon contaminated potting soil had lower total biomass and lower growth rates compared to the control

Phytoremediation of hydrocarbon-contaminated soil using plants adapted to western Canadian climate

Energy Technology Data Exchange (ETDEWEB)

Robson, D.B.

2003-07-01

Phytoremediation relies on the use of plants for in-situ treatment of hydrocarbon contaminated soils. It is based on relationships between plants, microorganisms and the environment. The advantages of the process are its low cost and minimal soil disturbance. Phytoremediation has not been widely implemented in Canada because only a few native or non-native plant species have been tested for hydrocarbon tolerance or degradation ability. More studies are needed to fully understand why some plants are more tolerant of hydrocarbons than others, and whether tolerant species increase hydrocarbon degradation. In this study, several field and growth chamber experiments were conducted to examine hydrocarbon tolerance in plants. Hydrocarbon contaminated field plots had higher soil pH, carbon to nitrogen ratio and bare ground, lower total nitrogen, available phosphorous and litter cover. The mean diversity at the uncontaminated sites was 0.52. It was 0.45 at the contaminated sites. Mean species similarity between contaminated and uncontaminated sites was 31.1 per cent and cover similarity was 22.2 per cent. The common plants in the contaminated field included kochia, wild barley, salt grass, bluegrass, and wheatgrass. The plants that formed most plant cover on contaminated plots were non-mycorrhizal, self-pollinating, and large seeded. The species with the highest survival after 5 weeks in hydrocarbon contaminated soils included one native and 4 non-native grasses, 2 native and 3 non-native legumes and 2 native forbs. All plants (with the exception of Indian breadroot) grown in hydrocarbon contaminated potting soil had lower total biomass and lower growth rates compared to the control.

Bioremediation of Polycyclic Aromatic Hydrocarbon contaminated ...

African Journals Online (AJOL)

This study investigates the effect of lead and chromium on the rate of bioremediation of polycyclic aromatic hydrocarbon (PAH) contaminated clay soil. Naphthalene was used as a target PAH. The soil was sterilized by heating at 120oC for one hour. 100g of the soil was contaminated with lead, chromium, nickel and mercury ...

Contamination of the eggs of raptors by chlorinated hydrocarbons between 1974 and 1980. [Falco peregrinus, Athene noctua, Falco tinnunculus

Energy Technology Data Exchange (ETDEWEB)

Venant, A.; Richou-Bac, L.; Gleizes, E.; Juillard, M.; Terrasse, M.; Terrasse, J.F.

1984-01-01

The contents of 206 unfertilized eggs (especially those of birds of prey) were analyzed for residues of chlorinated hydrocarbons (pesticides and PCB) from 1974 to 1980. Eggs collected in Jura (France and Switzerland) were sent deep-frozen to the laboratory. In 1974 and 1975, only 14 peregrine falcon Falco peregrinus eggs were received, and this study therefore really began in 1976. Since 1976, only peregrine falcon, little owl Athene noctua and lesser kestrel Falco tinnunculus eggs have been systematically analyzed. Other results are given for information. No important levels of cyclodienes or BHC were found, but only high levels for HCB, DDE and PCB residues. Of these three species, peregrine falcon eggs were the most contaminated (high level in food chain) but the pollutant levels have seemed to decrease. In 1976, the authors found 1.7 ..mu..g g..pi../sup 1/ HCB, 17.41 ..mu..g g/sup -1/ DDE and 9 ..mu..g g/sup -1/ PCB against 0.269 ..mu..g g/sup -1/ HCB, 5.84 ..mu..g g/sup -1/ DDE and 8.59 ..mu..g g/sup -1/ PCB in 1980 (it is important to record a very high PCB level in 1977 - 63 ..mu..g g/sup -1/. Residue levels were lower for other eggs such as lesser kestrel - 0.029 ..mu..g g/sup -1/ HCB, 0.099 ..mu..g g/sup -1/ DDE, and 0.24 ..mu..g g/sup -1/ PCB; or little owl eggs - 0.041 ..mu..g g/sup -1/ HCB, 1.18 ..mu..g g/sup -1/ DDE, and 0.652 ..mu..g g/sup -1/ PCB in 1980.

Syntrophic biodegradation of hydrocarbon contaminants.

Science.gov (United States)

Gieg, Lisa M; Fowler, S Jane; Berdugo-Clavijo, Carolina

2014-06-01

Anaerobic environments are crucial to global carbon cycling wherein the microbial metabolism of organic matter occurs under a variety of redox conditions. In many anaerobic ecosystems, syntrophy plays a key role wherein microbial species must cooperate, essentially as a single catalytic unit, to metabolize substrates in a mutually beneficial manner. Hydrocarbon-contaminated environments such as groundwater aquifers are typically anaerobic, and often methanogenic. Syntrophic processes are needed to biodegrade hydrocarbons to methane, and recent studies suggest that syntrophic hydrocarbon metabolism can also occur in the presence of electron acceptors. The elucidation of key features of syntrophic processes in defined co-cultures has benefited greatly from advances in 'omics' based tools. Such tools, along with approaches like stable isotope probing, are now being used to monitor carbon flow within an increasing number of hydrocarbon-degrading consortia to pinpoint the key microbial players involved in the degradative pathways. The metagenomic sequencing of hydrocarbon-utilizing consortia should help to further identify key syntrophic features and define microbial interactions in these complex communities. Copyright © 2013 Elsevier Ltd. All rights reserved.

Biological regeneration of carrier material for the adsorption of halogen hydrocarbons in plants for cleaning up contaminated groundwater. Final report. Biologische Regeneration von Traegermaterial fuer die Adsorption von Halogenkohlenwasserstoffen in Anlagen zur Sanierung kontaminierten Grundwassers. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Ressel, K

1993-06-01

Halogen hydrocarbons and above all chlorinated hydrocarbons are widespread harmful substances in soils and in groundwater. When cleaning up groundwater contamination, the contaminants are brought into the gas phase by strip processes. From the gas phase, the contaminants can be adsorbed on different carrier materials, mostly active carbon. One was searching for ways to regenerate this adsorption material. The mixed culture from a sea sediment most suitable for the decomposition of chlorinated hydrocarbons was optimized regarding its decomposition performance and was later used on the technical scale. In the decomposition experiments on the large technical scale, the cultures were lodged on filling bodies which has a much higher amount of gaps. In this case, an optimum supply of the micro-organisms with oxygen and methane is guaranteed, which is used as co-substrate. No intermediate product was found in a gas chromatography examination. The biologically occupied stage is situated between a desorption column and the active carbon filters, and reduces the load of harmful substances which can no longer be brought into the gas phase by stripping out. This has the advantage that it can be integrated in existing plants and can be adapted to any case of contamination by lodging adapted micro-organisms on it. The basis for each application must be separately researched. (orig.)

Biomarkers for redox-active genotoxins in contaminated sediments: A mechanistic approach

International Nuclear Information System (INIS)

Eufemia, N.A.; Beaty, B.B.; Reichert, P.; Watson, D.E.; Burns, T.A.

1993-04-01

Feral brown bullhead catfish and environmental sediments were collected from three sites in the Niagara River system in northern New York state. The sites were Black Creek, a relatively uncontaminated reference site; the Love Canal-102nd Street dump site which was principally contaminated with chlorinated hydrocarbons (CHs) and chlorinated pesticides; and a site in the Buffalo River which was principally contaminated with polycyclic aromatic hydrocarbons (PAHs). A variety of putative biomarkers of genotoxicity and/or oxidative stress were measured in hepatic tissues of these fish. The results indicate that metabolic indices of benthic animals can successfully be used as biomarkers of exposure to environmental contaminants, especially when a suite of responses is evaluated, and that strong associations between specific responses and classes of chemicals suggest that a further refinement of this approach is feasible

Contaminated environments in the subsurface and bioremediation: organic contaminants.

Science.gov (United States)

Holliger, C; Gaspard, S; Glod, G; Heijman, C; Schumacher, W; Schwarzenbach, R P; Vazquez, F

1997-07-01

Due to leakages, spills, improper disposal and accidents during transport, organic compounds have become subsurface contaminants that threaten important drinking water resources. One strategy to remediate such polluted subsurface environments is to make use of the degradative capacity of bacteria. It is often sufficient to supply the subsurface with nutrients such as nitrogen and phosphorus, and aerobic treatments are still dominating. However, anaerobic processes have advantages such as low biomass production and good electron acceptor availability, and they are sometimes the only possible solution. This review will focus on three important groups of environmental organic contaminants: hydrocarbons, chlorinated and nitroaromatic compounds. Whereas hydrocarbons are oxidized and completely mineralized under anaerobic conditions in the presence of electron acceptors such as nitrate, iron, sulfate and carbon dioxide, chlorinated and nitroaromatic compounds are reductively transformed. For the aerobic often persistent polychlorinated compounds, reductive dechlorination leads to harmless products or to compounds that are aerobically degradable. The nitroaromatic compounds are first reductively transformed to the corresponding amines and can subsequently be bound to the humic fraction in an aerobic process. Such new findings and developments give hope that in the near future contaminated aquifers can efficiently be remediated, a prerequisite for a sustainable use of the precious-subsurface drinking water resources.

Investigating hydrocarbon contamination using ground penetrating radar

International Nuclear Information System (INIS)

Roest, P.B. van der; Brasser, D.J.S.; Wagebaert, A.P.J.; Stam, P.H.

1996-01-01

The increasing costs of remediating contaminated sites has stimulated research for cost reducing techniques in soil investigation and clean-up techniques. Under the traditional approach soil borings and groundwater wells are used to investigate contaminated soil. These are useful tools to determine the amount and characteristics of the contamination, but they are inefficient and costly in providing information on the location and extent of contamination as they only give information on one point. This often leads to uncertainty in estimating clean-up costs or, even worse, to unsuccessful clean-ups. MAP Environmental Research has developed a technology using Ground Penetrating Radar (GPR) in combination with in-house developed software to locate and define the extent of hydrocarbon contamination. With this technology, the quality of site investigation is increased while costs are reduced. Since 1994 MAP has been improving its technology and has applied it to over 100 projects, which all have been checked afterwards by conventional drilling. This paper gives some general characteristics of the method and presents a case study. The emphasis of this paper lies on the practical application of GPR to hydrocarbon contamination detection

Removal of Chlorinated Chemicals in H2 Feedstock Using Modified Activated Carbon

Directory of Open Access Journals (Sweden)

Prapaporn Luekittisup

2015-01-01

Full Text Available Activated carbon (GAC was impregnated by sodium and used as adsorbent to remove chlorinated hydrocarbon (CHC gases contaminated in H2 feedstock. The adsorption was carried out in a continuous packed-bed column under the weight hourly space velocity range of 0.8–1.0 hr−1. The adsorption capacity was evaluated via the breakthrough curves. This modified GAC potentially adsorbed HCl and VCM of 0.0681 gHCl/gadsorbent and 0.0026 gVCM/gadsorbent, respectively. It showed higher adsorption capacity than SiO2 and Al2O3 balls for both organic and inorganic CHCs removal. In addition, the kinetic adsorption of chlorinated hydrocarbons on modified GAC fit well with Yoon-Nelson model.

New wash aid T-128 improves efficacy of chlorine against cross contamination by bacterial pathogens in fresh-cut lettuce processing

Science.gov (United States)

Chlorinated water is widely used as the primary anti-microbial intervention during fresh-cut produce processing. Free chlorine in chlorinated water can provide effective reduction of potential contaminations by microbial pathogens, and, more importantly, effectively prevent cross contamination of p...

Enhanced reductive dechlorination in clay till contaminated with chlorinated solvents

DEFF Research Database (Denmark)

Damgaard, Ida

Chlorinated solvents are among the most frequently found contaminants in groundwater. In fractured media, chlorinated ethenes and ethanes are transported downwards through preferential pathways with subsequent diffusion into the sediment matrix. Due to slow back diffusion it can serve as a long...... (direct push delivery, Gl. Kongevej). Degradation of chlorinated ethenes (and ethanes) in the clay till matrix and in embedded high permeability features was investigated by high resolution sampling of intact cores combined with groundwater sampling. An integrated approach using chemical analysis...... (hydraulic fracturing with gravitational injection and direct push delivery) were therefore tested in clay till by injection of amendment-comparable tracers to investigate the possibility to overcome diffusion limitations in the low permeability matrix. The study of hydraulic fracturing demonstrated...

A stable isotope approach for source apportionment of chlorinated ethene plumes at a complex multi-contamination events urban site

Science.gov (United States)

Nijenhuis, Ivonne; Schmidt, Marie; Pellegatti, Eleonora; Paramatti, Enrico; Richnow, Hans Hermann; Gargini, Alessandro

2013-10-01

The stable carbon isotope composition of chlorinated aliphatic compounds such as chlorinated methanes, ethanes and ethenes was examined as an intrinsic fingerprint for apportionment of sources. A complex field site located in Ferrara (Italy), with more than 50 years history of use of chlorinated aliphatic compounds, was investigated in order to assess contamination sources. Several contamination plumes were found in a complex alluvial sandy multi-aquifer system close to the river Po; sources are represented by uncontained former industrial and municipal dump sites as well as by spills at industrial areas. The carbon stable isotope signature allowed distinguishing 2 major sources of contaminants. One source of chlorinated aliphatic contaminants was strongly depleted in 13C (-40‰ which is commonly observed in recent production of chlorinated solvents. The degradation processes in the plumes could be traced interpreting the isotope enrichment and depletion of parent and daughter compounds, respectively. We demonstrate that, under specific production conditions, namely when highly chlorinated ethenes are produced as by-product during chloromethanes production, 13C depleted fingerprinting of contaminants can be obtained and this can be used to track sources and address the responsible party of the pollution in urban areas.

Intercalibration of analytical methods on marine environmental samples. Results of MEDPOL-II exercise for the intercalibration of chlorinated hydrocarbon measurements on mussel homogenate (MA-M-2/OC)

International Nuclear Information System (INIS)

1986-10-01

Mussels have been considered as good indicators of chlorinated hydrocarbon pollution of the marine environment and this led to the development of mussel watch programmes in many countries in the late seventies. These intercalibration exercises were arranged in order to increase the quality of analytical capabilities of environmental laboratories. The samples MA-M-2/0C of Mediterranean mussels with chlorinated hydrocarbon content were checked by 27 laboratories. It was judged highly suitable for these laboratories to have at their disposal a reference material made of mussel tissue with robust estimations of the true values with respect to several chlorinated hydrocarbons. Such a material would allow chemists to check the validity of new analytical procedures

Distinguishing natural hydrocarbons from anthropogenic contamination in ground water

International Nuclear Information System (INIS)

Lesage, S.; Xu, H.; Novakowski, K.S.

1997-01-01

Differentiation between natural and anthropogenic sources of ground-water contamination by petroleum hydrocarbons is necessary in areas where natural hydrocarbons may be present in the subsurface. Because of the similarity in composition between natural and refined petroleum, the use of statistical techniques to discern trends is required. In this study, both multivariate plotting techniques and principal component analysis were used to investigate the origin of hydrocarbons from a variety of study sites. Ground-water and gas samples were collected from the Niagara Falls area and from three gasoline stations where leaking underground storage tanks had been found. Although soil gas surveys are used to indicate the presence of hydrocarbons, they were not useful in differentiating between natural and anthropogenic sources of contamination in ground water. Propane and pentene were found to be the most useful chemical parameters in discriminating between the natural and anthropogenic sources. These chemicals are not usually measured in investigations of ground-water contamination, yet analysis can be conducted by most environmental laboratories using conventional methods

Reproductive success and chlorinated hydrocarbon contamination of resident great blue herons (Ardea herodias) from coastal British Columbia, Canada, 1977 to 2000

International Nuclear Information System (INIS)

Harris, M.L.; Elliott, J.E.; Butler, R.W.; Wilson, L.K.

2003-01-01

Human disturbance and loss of nesting habitat were more important factors than chlorinated hydrocarbons in changing heron reproductive success. - Over the period 1977-2000, eggs of Pacific great blue heron (Ardea herodias fannini) were collected from 23 colonies along the southern coast of British Columbia, Canada, and analyzed for persistent organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs). Concentrations of OC pesticides in eggs declined sharply in the late 1970s, after which there were minimal changes. The sums of PCB congeners were not reduced appreciably during the 1980s and 1990s, but Aroclor 1260 concentrations suggested a sharp decline in PCB contamination of eggs in the late 1970s, similar to that shown for OC pesticides. Eggs collected along or near the Fraser River delta showed higher levels of most pesticides compared to other monitored colonies. Although the delta lands support a long-standing agricultural economy, the primary factors influencing OC levels in the delta colonies were thought to be driven by estuarine processes. We suggest two possible influencing factors were: 1) a greater rate of bioaccumulation in the estuary due to the deposition of particulates collected over a vast area encompassed by the Fraser River watershed; or 2) a higher rate of biomagnification in the estuary due to species differences at lower trophic levels of the heron food chain. Eggs from urban colonies contained higher levels of PCBs. The congener pattern was not clearly different from that observed in less contaminated eggs from rural and pulp mill-influenced colonies, except that colonies in Vancouver had greater proportions of PCB-66, suggesting a local source of Aroclor 1242. Productivity in the coastal heron colonies was highly variable over the period of study, with 71% of recorded colony-wide reproductive failures occurring in colonies near pulp mills. However, the predominant factors influencing reproductive success were probably disturbance

Comparative analysis of concentrations of lead, cadmium and mercury in cord blood, maternal blood, and breast milk, as well as persistent chlorinated hydrocarbons in maternal milk samples from Germany and Iran

International Nuclear Information System (INIS)

Javanmardi, F.

2001-01-01

The concentration of the heavy metals lead, cadmium and mercury in cord blood, maternal blood and breast milk has been studied. Lead and cadmium were analyzed by atomic absorption spectrometry. Mercury was determined using the flow-injection hydride technique. According to the concentrations of heavy metals and chlorinated hydrocarbons we ascertained for the region of Rendsburg, the toxic risk for infants relative to the consumption of contaminated maternal milk can be viewed as very slight. (orig.) [de

Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses.

Science.gov (United States)

Schambach, B T; Berrang, M E; Harrison, M A; Meinersmann, R J

2014-09-01

Immersion chilling of broiler carcasses can be a site for cross-contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as an antimicrobial but can be overcome by organic material. A proprietary chlorine stabilizer (T-128) based on phosphoric acid-propylene glycol was tested as a chill tank additive in experiments simulating commercial broiler chilling. In bench-scale experiments, 0.5% T-128 was compared with plain water (control), 50 ppm of chlorine, and the combination of 0.5% T-128 with 50 ppm of chlorine to control transfer of Salmonella and Campylobacter from inoculated wing drummettes to co-chilled uninoculated drummettes. Both chlorine and T-128 lessened cross-contamination with Salmonella (P additional experiment demonstrated that the antimicrobial effect of T-128 was not due merely to a lower pH. In commercial broiler chilling, a pH close to 6.0 is preferred to maximize chlorine effectiveness, while maintaining water-holding capacity of the meat. In a set of pilot-scale experiments with T-128, a near-ideal pH of 6.3 was achieved by using tap water instead of the distilled water used in bench-scale experiments. Pilot-scale chill tanks were used to compare the combination of 0.5% T-128 and 50 ppm of chlorine with 50 ppm of plain chlorine for control of cross-contamination between whole carcasses inoculated with Salmonella and Campylobacter and co-chilled uninoculated carcasses. The T-128 treatment resulted in significantly less crosscontamination by either direct contact or water transfer with both organisms compared with plain chlorine treatment. T-128 may have use in commercial broiler processing to enhance the effectiveness of chlorine in processing water.

Intrinsic bioremediation of petroleum hydrocarbons in a gas condensate-contaminated aquifer

International Nuclear Information System (INIS)

Gieg, L.M.; McInerney; Tanner, R.S.; Harris, S.H. Jr.; Sublette, K.L.; Suflita, J.M.; Kolhatkar, R.V.

1999-01-01

A study was designed to determine if the intrinsic bioremediation of gas condensate hydrocarbons represented an important fate process in a shallow aquifer underlying a natural gas production site. For over 4 yr, changes in the groundwater, sediment, and vadose zone chemistry in the contaminated portion of the aquifer were interpreted relative to a background zone. Changes included decreased dissolved oxygen and sulfate levels and increased alkalinity, Fe(II), and methane concentrations in the contaminated groundwater, suggesting that aerobic heterotrophic respiration depleted oxygen reserves leaving anaerobic conditions in the hydrocarbon-impacted subsurface. Dissolved hydrogen levels in the contaminated groundwater indicated that sulfate reduction and methanogenesis were predominant biological processes, corroborating the geochemical findings. Furthermore, 10--1000-fold higher numbers of sulfate reducers and methanogens were enumerated in the contaminated sediment relative to background. Putative metabolites were also detected in the contaminated groundwater, including methylbenzylsuccinic acid, a signature intermediate of anaerobic xylene decay. Laboratory incubations showed that benzene, toluene, ethylbenzene, and each of the xylene isomers were biodegraded under sulfate-reducing conditions as was toluene under methanogenic conditions. These results coupled with a decrease in hydrocarbon concentrations in contaminated sediment confirm that intrinsic bioremediation contributes to the attenuation of hydrocarbons in this aquifer

Characterization of the vadose zone above a shallow aquifer contaminated with gas condensate hydrocarbons

International Nuclear Information System (INIS)

Sublette, K.; Duncan, K.; Thoma, G.; Todd, T.

2002-01-01

A gas production site in the Denver Basin near Ft. Lupton, Colorado has leaked gas condensate hydrocarbons from an underground concrete tank used to store produced water. The leak has contaminated a shallow aquifer. Although the source of pollution has been removed, a plume of hydrocarbon contamination still remains for nearly 46 m from the original source. An extensive monitoring program was conducted in 1993 of the groundwater and saturated sediments. The objective was to determine if intrinsic aerobic or anaerobic bioremediation of hydrocarbons occurred at the site at a rate that would support remediation. Geochemical indicators of hydrogen biodegradation by microorganisms in the saturated zone included oxygen depletion, increased alkalinity, sulfate depletion, methane production and Fe2+ production associated with hydrogen contamination. The presence of sulfate-reducing bacteria and methanogens was also much higher in the contaminated sediments. Degraded hydrocarbon metabolites were found in contaminated groundwater. An extensive characterization of the vadose zone was conducted in which the vadose zone was sample in increments of 15 cm from the surface to the water table at contaminated and non contaminated sites. The samples were tested for individual C3+ hydrocarbons, methane, CO2, total organic carbon, total inorganic carbon, and total petroleum hydrocarbons. The vadose zone consisted of an active and aerobic bioreactor fueled by condensate hydrocarbons transported into the unsaturated zone by evaporation of hydrocarbons at the water table. It was concluded that the unsaturated zone makes an important contribution to the natural attenuation of gas condensate hydrocarbons in the area. 17 refs., 2 tabs., 28 figs

In Situ Treatment of Chlorinated Ethene-Contaminated Groundwater Using horizontal Flow Treatment Wells

National Research Council Canada - National Science Library

Ferland, Derek

2000-01-01

The limitations of conventional containment technologies for groundwater contaminated with chlorinated solvents have motivated development of innovative technologies to achieve national groundwater...

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.

Rush-hour aromatic and chlorinated hydrocarbons in selected subway stations of Shanghai, China.

Science.gov (United States)

Zhang, Yanli; Li, Chunlei; Wang, Xinming; Guo, Hai; Feng, Yanli; Chen, Jianmin

2012-01-01

Air samples were collected simultaneously at platform, mezzanine and outdoor in five typical stations of subway system in Shanghai, China using stainless steel canisters and analyzed by gas chromatography-mass selective detector (GC-MSD) after cryogenic preconcentration. Benzene, toluene, ethylbenzene and xylenes (BTEX) at the platforms and mezzanines inside the stations averaged (10.3 +/- 2.1), (38.7 +/- 9.0), (19.4 +/- 10.1) and (30.0 +/- 11.1) microg/m3, respectively; while trichloroethylene (TrCE), tetrachloroethylene (TeCE) and para-dichlorobenzene (pDCB), vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of (3.6 +/- 1.3), (1.3 +/- 0.5), (4.1 +/- 1.1), (2.2 +/- 1.1) and (1.2 +/- 0.3) microg/m3, respectively. Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor (platforms and mezzanines) than outdoor with average indoor/outdoor (I/O) ratios of 1.1-9.5, whereas no significant indoor/outdoor differences were found except for benzene and TrCE. The highly significant mutual correlations (p subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source. TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air, especially in the mezzanines.

Push-Pull Tests for Evaluating the Aerobic Cometabolism of Chlorinated Aliphatic Hydrocarbons: Cost & Performance Report

National Research Council Canada - National Science Library

Semprini, Lew

2006-01-01

.... This report describes a newly developed single-well technology for evaluating the feasibility of using in situ aerobic cometabolic processes to treat groundwater contaminated with chlorinated solvent mixtures...

Sensitivity ranking for freshwater invertebrates towards hydrocarbon contaminants.

Science.gov (United States)

Gerner, Nadine V; Cailleaud, Kevin; Bassères, Anne; Liess, Matthias; Beketov, Mikhail A

2017-11-01

Hydrocarbons have an utmost economical importance but may also cause substantial ecological impacts due to accidents or inadequate transportation and use. Currently, freshwater biomonitoring methods lack an indicator that can unequivocally reflect the impacts caused by hydrocarbons while being independent from effects of other stressors. The aim of the present study was to develop a sensitivity ranking for freshwater invertebrates towards hydrocarbon contaminants, which can be used in hydrocarbon-specific bioindicators. We employed the Relative Sensitivity method and developed the sensitivity ranking S hydrocarbons based on literature ecotoxicological data supplemented with rapid and mesocosm test results. A first validation of the sensitivity ranking based on an earlier field study has been conducted and revealed the S hydrocarbons ranking to be promising for application in sensitivity based indicators. Thus, the first results indicate that the ranking can serve as the core component of future hydrocarbon-specific and sensitivity trait based bioindicators.

MULTICOMPONENT DETERMINATION OF CHLORINATED HYDROCARBONS USING A REACTION-BASED CHEMICAL SENSOR .2. CHEMICAL SPECIATION USING MULTIVARIATE CURVE RESOLUTION

NARCIS (Netherlands)

Tauler, R.; Smilde, A. K.; HENSHAW, J. M.; BURGESS, L. W.; KOWALSKI, B. R.

1994-01-01

A new multivariate curve resolution method that can extract analytical information from UV/visible spectroscopic data collected from a reaction-based chemical sensor is proposed. The method is demonstrated with the determination of mixtures of chlorinated hydrocarbons by estimating the kinetic and

Bioremediation: Technology for treating hydrocarbon-contaminated wastewater

Energy Technology Data Exchange (ETDEWEB)

Towprayoon, S.; Kuntrangwattana, S. [King Mongkut`s Institute of Technology, Bangkok (Thailand)

1996-12-31

Cutting oil wastewater from an iron and steel factory was applied to the soil windrow. Self-remediation was then compared with remediation with acclimatized indigenous microbes. The incremental reduction rate of the microorganisms and hydrocarbon-degradable microbes was slower in self-remediation than in the latter treatment. Within 30 days, when the acclimatized indigenous microbes were used, there was a significant reduction of the contaminated hydrocarbons, while self-remediation took longer to reduce to the same concentration. Various nitrogen sources were applied to the soil pile, namely, organic compost, chemical fertilizer, ammonium sulfate, and urea. The organic compost induced a high yield of hydrocarbon-degradable microorganisms, but the rate at which the cutting oil in the soil decreased was slower than when other nitrogen sources were used. The results of cutting oil degradation studied by gas chromatography showed the absence of some important hydrocarbons. The increment of the hydrocarbon-degradable microbes in the land treatment ecosystem does not necessarily correspond to the hydrocarbon reduction efficiency. 3 refs., 3 figs.

Determination of chlorinated hydrocarbons in single and multi component test gases

Energy Technology Data Exchange (ETDEWEB)

Giese, U.; Stenner, H. (Paderborn Univ. (Gesamthochschule) (Germany, F.R.). Angewandte Chemie); Ludwig, E.; Kettrup, A. (Paderborn Univ. (Gesamthochschule) (Germany, F.R.). Angewandte Chemie Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany, F.R.). Inst. fuer Oekologische Chemie)

1990-11-01

For comparing the efficiency of active and diffusive sampling methods two diffusive samplers with different properties were used to determine chlorinated hydrocarbons (CH{sub 2}Cl{sub 2}, CHCl{sub 3}, CCl{sub 4}) in single and multi component test gas mixtures. One of the chosen diffusive samplers can also be used for active sampling. In general, good correlations of all tested methods could be observed in the direct comparison of active and diffusive sampling and in the determination of the efficiencies. During the application of active and diffusive sampling methods in multi component test gases of the analytes possible interferences could not be ascertained. (orig.).

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

Comparison of the environmental impacts of two remediation technologies used at hydrocarbon contaminated sites

International Nuclear Information System (INIS)

Viikala, R.; Kuusola, J.

2000-01-01

Investigation and remediation of contaminated sites has rapidly increased in Finland during the last decade. Public organisations as well as private companies are investigating and remediating their properties, e.g. redevelopment or business transactions. Also numerous active and closed gasoline stations have been investigated and remediated during the last few years. Usually the contaminated sites are remediated to limit values regardless of the risk caused by contamination. The limit values currently used in Finland for hydrocarbon remediation at residential or ground water areas are 300 mg/kg of total hydrocarbons and 100 mg/kg of volatile hydrocarbons (boiling point < appr. 200 deg C). Additionally, compounds such as aromatic hydrocarbons have specific limit values. Remediation of hydrocarbon contaminated sites is most often carried out by excavating the contaminated soil and taking it to a landfill by lorries. As distances from the sites to landfills are generally rather long, from tens of kilometres to few hundred kilometres, it is evident that this type of remediation has environmental impacts. Another popular technology used at sites contaminated by volatile hydrocarbons is soil vapour extraction (SVE). SVE is a technique of inducing air flow through unsaturated soils by vapour extraction wells or pipes to remove organic contaminants with an off-gas treatment system. The purpose of this study was to evaluate some of the environmental impacts caused by remediation of hydrocarbon contaminated soil. Energy consumption and air emissions related remedial activities of the two methods were examined in this study. Remediation of the sites used in this study were carried out by Golder Associates Oy in different parts of Finland in different seasons. Evaluation was made by using life cycle assessment based approach

Application of chlorine dioxide to lessen bacterial contamination during broiler defeathering

Science.gov (United States)

Due to escape of contaminated gut contents, the number of Campylobacter spp. recovered from broiler carcasses increases during feather removal. Chlorine dioxide (ClO2) is approved for use as an antimicrobial treatment during poultry processing. A study was designed to test if application of 50 ppm...

Anaerobic Transformation of Chlorinated Aliphatic Hydrocarbons in a Sand Aquifer Based on Spatial Chemical Distributions

Science.gov (United States)

Semprini, Lewis; Kitanidis, Peter K.; Kampbell, Don H.; Wilson, John T.

1995-04-01

We estimated the distribution of chlorinated aliphatic hydrocarbons (CAHs) from groundwater samples collected along three transects in a sand aquifer. Trichloroethylene (TCE) leaked and contaminated the aquifer probably more than a decade before we collected the measurements. The data show significant concentrations of TCE, cis-l,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethene. We attributed DCE, VC, and ethene to the reductive dehalogenation of TCE. The CAH concentrations varied significantly with depth and correlate with sulfate and methane concentrations. Anoxic aquifer conditions exist with methane present at relatively high concentrations at depth. High concentrations of TCE correspond with the absence of methane or low methane concentrations, whereas products of TCE dehalogenation are associated with higher methane concentrations and low sulfate concentrations. Indications are that the dechlorination of TCE and DCE to VC and ethene is associated with sulfate reduction and active methanogenesis. TCE dechlorination to DCE is likely occurring under the less reducing conditions of sulfate reduction, with further reductions to VC and ethene occurring under methanogenic conditions. We estimated that about 20% of TCE has dechlorinated to ethene. The analysis of the data enhanced our knowledge of natural in situ transformation and transport processes of CAHs.

Subsurface biogenic gas rations associated with hydrocarbon contamination

International Nuclear Information System (INIS)

Marrin, D.L.

1991-01-01

Monitoring the in situ bioreclamation of organic chemicals in soil is usually accomplished by collecting samples from selected points during the remediation process. This technique requires the installation and sampling of soil borings and does not allow for continuous monitoring. The analysis of soil vapor overlying hydrocarbon-contaminated soil and groundwater has been used to detect the presence of nonaqueous phase liquids (NAPL) and to locate low-volatility hydrocarbons that are not directly detected by more conventional soil gas methods. Such soil vapor sampling methods are adaptable to monitoring the in situ bioremediation of soil and groundwater contamination. This paper focuses on the use of biogenic gas ratio in detecting the presence of crude oil and gasoline in the subsurface

Petroleum Hydrocarbons Contamination Profile of Ochani Stream in ...

African Journals Online (AJOL)

Michael Horsfall

ABSTRACT: Petroleum hydrocarbon contamination profile, heavy metals and .... potential conduits for oil and water migrating from the ... by Gas Chromatography: Soil / sediment / sludge ..... fractions contained in the dump pits) which have.

Migration of chlorinated hydrocarbons in multilayer unconsolidated porous media: a case study from the Po Plain, Italy

Directory of Open Access Journals (Sweden)

Maria Filippini

2017-12-01

Full Text Available Chlorinated solvents are the most ubiquitous organic contaminants found in groundwater since the last six decades. Due to their high degree of carcinogenicity/toxicity and the relatively high mobility and persistence, they represent a serious threat against the human health and the environment. These contaminants generally reach groundwater as Dense Non-Aqueous Phase Liquid (DNAPL that can migrate through aquifers easier than aqueous contaminants. The complex phase partitioning to which chlorinated solvent DNAPLs can undergo (i.e. to the dissolved, vapor or sorbed phase, as well as their transformations (e.g. degradation, depend on the physico-chemical properties of the contaminants and on the features of the hydrogeological system in which they migrate. The hydrogeologic setting below the city of Ferrara (Po plain, northern Italy, which is affected by scattered contamination by chlorinated solvents, has been investigated. In particular, a limited-inspace high-resolution investigation was performed in one selected contaminated test-site, known as “Caretti site”. Here, high-resolution vertical profiling of different kind of data (i.e. stratigraphic data, hydraulic heads, hydrochemical composition of water, stable isotopes of water and contaminants were collected by means of multilevel monitoring systems and other innovative sampling and analytical techniques. The main goals of the research were to assess the intrinsic vulnerability of the aquifers and to identify the dynamics of migration and transformation of the chloroethene contaminants in relationship to the features of the hosting porous medium. The confined aquifers turned out to be more vulnerable to DNAPLs than aqueous contaminants due to the occurrence of microfractures in the overlying clayey aquitards. The presence of organic-rich deposits in the local stratigraphy enhanced the biodegradation of chloroethenes causing accumulation of Vinyl Chloride. The results are useful at the

Chlorine dioxide as phenol and H2S scavenger - formation of halogenated phenols and subsequent environmental risk

Energy Technology Data Exchange (ETDEWEB)

Melbye, Alf G.; Faksness, Liv-Guri; Knudsen, Boerre Leif

2006-03-15

Formation of halogenated phenols as side products from treatment of produced water with aqueous chlorine dioxide has been investigated. The literature describes formation of halogenated hydrocarbons in effluent treatment using chlorine, hypochlorite and chlorine dioxide. A new chlorine dioxide product, originally intended as a H2S scavenger in the oil and gas industry, has been tested both as a phenol scavenger and H2S-scavenger for produced water applications. The concern about the possible formation of halogenated by-products initiated laboratory testing of chlorine dioxide as phenol and H2S scavenger for produced water applications. The tests also included synthetic matrixes containing phenols, and the tests show that halogenated phenols, mainly brominated species, are found in produced water after treatment with chlorine dioxide. Due to potential environmental risk from halogenated organic contaminants, the use of chlorine dioxide as phenol and H2S scavenger is not recommended. (Author)

Regulatory approaches to hydrocarbon contamination from underground storage tanks

International Nuclear Information System (INIS)

Daugherty, S.J.

1991-01-01

Action or lack of action by the appropriate regulatory agency is often the most important factor in determining remedial action or closure requirements for hydrocarbon contaminated sites. This paper reports that the diversity of regulatory criteria is well known statewide and well documented nationally. In California, the diversity of approaches is due to: that very lack of a clear understanding of the true impact of hydrocarbon contamination: lack of state or federal standards for soil cleanup, and state water quality objectives that are not always achievable; vagueness in the underground storage tank law; and the number and diversity of agencies enforcing the underground storage tank regulations

Natural attenuation of diesel aliphatic hydrocarbons in contaminated agricultural soil

International Nuclear Information System (INIS)

Serrano, Antonio; Gallego, Mercedes; Gonzalez, Jose Luis; Tejada, Manuel

2008-01-01

A diesel fuel spill at a concentration of 1 L m -2 soil was simulated on a 12 m 2 plot of agricultural land, and natural attenuation of aliphatic hydrocarbons was monitored over a period of 400 days following the spill after which the aliphatic hydrocarbon concentrations were found to be below the legal contamination threshold for soil. The main fraction of these compounds (95%) remained at the surface layer (0-10 cm). Shortly after the spill (viz. between days 0 and 18), evaporation was the main origin of the dramatic decrease in pollutant concentrations in the soil. Thereafter, soil microorganisms used aliphatic hydrocarbons as sources of carbon and energy, as confirmed by the degradation ratios found. Soil quality indicators, soil microbial biomass and dehydrogenase activity, regained their original levels about 200 days after the spill. - The effect of aliphatic hydrocarbons contamination on soil quality was monitored over a period of 400 days after a Diesel fuel spill

Chlorinated aliphatic and aromatic VOC decomposition in air mixture by using electron beam irradiation

International Nuclear Information System (INIS)

Chmielewski, A.G.; Sun Yongxia; Bulka, S.; Zimek, Z.

2004-01-01

Chlorinated aliphatic and aromatic hydrocarbons, which are emitted from coal power station and waste incinerators, are very harmful to the environment and human health. Recent studies show that chlorinated aliphatic and aromatic hydrocarbons are suspected to be the precursors of dioxin's formation. Dioxin's emission into atmosphere will cause severe environmental problems by ecology contamination. l,4-dichlorobenzene(l,4-DCB) and cis-dichloroethylene(cis-DCE) were chosen as representative chlorinated aromatic and aliphatic compounds, respectively. Their decomposition was investigated by electron beam irradiation. The experiments were carried out 'in batch' system. It is found that over 97% cis-DCE is decomposed having an initial concentration of 661 ppm. G-values of cis-DCE decomposition vary from 10 to 28 (molecules/100 eV) for initial concentration of 270-1530 ppm cis-DCE. The decomposition is mainly caused by secondary electron attachment and Cl addition reactions. Comparing with cis-DCE, 1,4-DCB decomposition needs higher absorbed dose. G-value of 1,4-DCB is below 4 molecules/100 eV

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)

Plant residues--a low cost, effective bioremediation treatment for petrogenic hydrocarbon-contaminated soil.

Science.gov (United States)

Shahsavari, Esmaeil; Adetutu, Eric M; Anderson, Peter A; Ball, Andrew S

2013-01-15

Petrogenic hydrocarbons represent the most commonly reported environmental contaminant in industrialised countries. In terms of remediating petrogenic contaminated hydrocarbons, finding sustainable non-invasive technologies represents an important goal. In this study, the effect of 4 types of plant residues on the bioremediation of aliphatic hydrocarbons was investigated in a 90 day greenhouse experiment. The results showed that contaminated soil amended with different plant residues led to statistically significant increases in the utilisation rate of Total Petroleum Hydrocarbon (TPH) relative to control values. The maximum TPH reduction (up to 83% or 6800 mg kg(-1)) occurred in soil mixed with pea straw, compared to a TPH reduction of 57% (4633 mg kg(-1)) in control soil. A positive correlation (0.75) between TPH reduction rate and the population of hydrocarbon-utilising microorganisms was observed; a weaker correlation (0.68) was seen between TPH degradation and bacterial population, confirming that adding plant materials significantly enhanced both hydrocarbonoclastic and general microbial soil activities. Microbial community analysis using Denaturing Gradient Gel Electrophoresis (DGGE) showed that amending the contaminated soil with plant residues (e.g., pea straw) caused changes in the soil microbial structure, as observed using the Shannon diversity index; the diversity index increased in amended treatments, suggesting that microorganisms present on the dead biomass may become important members of the microbial community. In terms of specific hydrocarbonoclastic activity, the number of alkB gene copies in the soil microbial community increased about 300-fold when plant residues were added to contaminated soil. This study has shown that plant residues stimulate TPH degradation in contaminated soil through stimulation and perhaps addition to the pool of hydrocarbon-utilising microorganisms, resulting in a changed microbial structure and increased alkB gene

Chlorinated hydrocarbons in the marine environment. A report prepared by the Panel on Monitoring Persistent Pesticides in the Marine Environment of the Committee on Oceanography

Science.gov (United States)

,; Goldberg, E.D.; Butler, P.; Meier, P.; Menzel, D.; Paulik, G.; Risebrough, R.; Stickel, L.F.

1971-01-01

SUMMARY AND RECOMMENDATIONS : The oceans are an ultimate accumulation site for the persistent chlorinated hydrocarbons. As much as 25 percent of the DDT compounds produced to date may have been transferred to the sea. The amount of DDT compounds in the marine biota is estimated to be less than 0.1 percent of total production, yet this amount has produced a demonstrable impact upon the marine environment. Populations of fish-eating birds have experienced reproductive failure and decline. With continued accumulations of persistent chlorinated hydrocarbons in the marine ecosystem, additional species will be threatened. Continued release of these pollutants to the environment can only accelerate the accumulation of unacceptable levels of persistent chlorinated hydrocarbons in the tissues of marine food fish. Certain risks in the utilization of chlorinated hydrocarbons are especially hard to quantify, but they require serious consideration. The rate at which such substances degrade to harmless products in the marine system is unknown; the half-lives of some of the more persistent materials are certainly of the order of years, and perhaps even of decades or centuries. If most of the remaining 75 percent of the persistent chlorinated hydrocarbons is now in reservoirs that will in time transfer their contents to the sea, we may expect an increased level of these substances in marine organisms, despite future improvements of manufacturing practices. In fact, if these compounds degrade with half-lives of decades or longer, there will be no opportunity to redress the consequences. The more the problems are studied, the more unexpected effects are identified. In view of the findings of the past decade, our prediction of the potential hazards of chlorinated hydrocarbons in the marine environment may be vastly underestimated. The Panel makes the following recommendations, which will be developed and expanded in the remainder of the report: ? A massive national effort should be

Assessing chlorinated ethene degradation in a large scale contaminant plume by dual carbon–chlorine isotope analysis and quantitative PCR

DEFF Research Database (Denmark)

Hunkeler, D.; Abe, Y.; Broholm, Mette Martina

2011-01-01

The fate of chlorinated ethenes in a large contaminant plume originating from a tetrachloroethene (PCE) source in a sandy aquifer in Denmark was investigated using novel methods including compound-specific carbon and chlorine isotope analysis and quantitative real-time polymerase chain reaction (q...... reduction by pyrite as indicated by the formation of cDCE and stable carbon isotope data. TCE and cDCE showed carbon isotope trends typical for reductive dechlorination with an initial depletion of 13C in the daughter products followed by an enrichment of 13C as degradation proceeded. At 1000 m downgradient......DCE. The significant enrichment of 13C in VC indicates that VC was transformed further, although the mechanismcould not be determined. The transformation of cDCEwas the rate limiting step as no accumulation of VC occurred. In summary, the study demonstrates that carbon–chlorine isotope analysis and qPCR combinedwith...

In-situ treatment of a mixed hydrocarbon plume through a permeable reactive barrier and enhanced bio-remediation

International Nuclear Information System (INIS)

Aglietto, I.; Bretti, L.L.

2005-01-01

Groundwater is frequently polluted with mixtures of contaminants that are amenable to different types of remediation. One example is the combination of petroleum hydrocarbons (mostly BTEX) and chlorinated solvents (chlorinated ethenes and propanes), as it occurs in the groundwater beneath the industrial site that is the objective of the present case study. The site is located in Italy near a main river (Arno), which is supposed to be the final recipient of the contamination and where a possible exposure might take place. The aim of the treatment is the plume containment within the site boundaries in order to avoid further migration of the contaminants towards the river. The design of the remediation system was based on an extensive site characterization that included - but was not limited to - the following information: geological and geochemical, microbiological and hydrological data, together with analytical data (i.e. contaminant concentrations). Pilot tests were also implemented in order to collect the necessary parameters for the full-scale treatment design and calibration. The site was contaminated by a mixed plume of more than 30 different contaminants, ranging from BTEX, to MTBE, to PAH, to chlorinated solvents. The concentration peaks were in the order of 1-100 mg/l for each contaminant. Petroleum hydrocarbons are quickly degradable through oxidative mechanisms (especially aerobic biodegradation), whereas fully-chlorinated compounds are only degradable via reductive pathways. A mixed plume of both types of contaminants therefore requires a combined approach with the application of different treatment technologies. The remediation strategy elaborated combines a permeable reactive barrier (PRB) in a funnel and gate configuration for the down-gradient plume containment, with the enhanced bio-remediation of the contaminants for the control of the plume boundaries and for the abatement of the concentration peaks. Pilot tests were carried out in order to assess

Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil.

Science.gov (United States)

Li, Xiaojing; Wang, Xin; Ren, Zhiyong Jason; Zhang, Yueyong; Li, Nan; Zhou, Qixing

2015-12-01

Bioelectrochemical system is an emerging technology for the remediation of soils contaminated by petroleum hydrocarbons. However, performance of such systems can be limited by the inefficient mass transport in soil. Here we report a new method of sand amendment, which significantly increases both oxygen and proton transports, resulting to increased soil porosity (from 44.5% to 51.3%), decreased Ohmic resistance (by 46%), and increased charge output (from 2.5 to 3.5Cg(-1)soil). The degradation rates of petroleum hydrocarbons increased by up to 268% in 135d. The degradation of n-alkanes and polycyclic aromatic hydrocarbons with high molecular weight was accelerated, and denaturing gradient gel electrophoresis showed that the microbial community close to the air-cathode was substantially stimulated by the induced current, especially the hydrocarbon degrading bacteria Alcanivorax. The bioelectrochemical stimulation imposed a selective pressure on the microbial community of anodes, including that far from the cathode. These results suggested that sand amendment can be an effective approach for soil conditioning that will enhances the bioelectrochemical removal of hydrocarbons in contaminated soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

SIMULATION OF PERFORMANCE OF CHLORINE-FREE FLURORINATED ETHERS AND FLUORINATED HYDROCARBONS TO REPLACE CFC-11 AND CFC-114 IN CHILLERS

Science.gov (United States)

The paper discusses simulation of the performance of chlorine-free fluorinated ethers and fluorinated hydrocarbons as potential long-term replacements for CFC-11 and -114. Modeling has been done with in-house refrigeration models based on the Carnahan-Starling-DeSantis Equation o...

Mineralisation of target hydrocarbons in three contaminated soils from former refinery facilities.

Science.gov (United States)

Towell, Marcie G; Bellarby, Jessica; Paton, Graeme I; Coulon, Frédéric; Pollard, Simon J T; Semple, Kirk T

2011-02-01

This study investigated the microbial degradation of (14)C-labelled hexadecane, octacosane, phenanthrene and pyrene and considered how degradation might be optimised in three genuinely hydrocarbon-contaminated soils from former petroleum refinery sites. Hydrocarbon mineralisation by the indigenous microbial community was monitored over 23 d. Hydrocarbon mineralisation enhancement by nutrient amendment (biostimulation), hydrocarbon degrader addition (bioaugmentation) and combined nutrient and degrader amendment, was also explored. The ability of indigenous soil microflora to mineralise (14)C-target hydrocarbons was appreciable; ≥ 16% mineralised in all soils. Generally, addition of nutrients or degraders increased the rates and extents of mineralisation of (14)C-hydrocarbons. However, the addition of nutrients and degraders in combination had a negative effect upon (14)C-octacosane mineralisation and resulted in lower extents of mineralisation in the three soils. In general, the rates and extents of mineralisation will be dependent upon treatment type, nature of the contamination and adaptation of the ingenious microbial community. Copyright © 2010 Elsevier Ltd. All rights reserved.

A statistical approach to evaluate hydrocarbon remediation in the unsaturated zone

International Nuclear Information System (INIS)

Hajali, P.; Marshall, T.; Overman, S.

1991-01-01

This paper presents an evaluation of performance and cleanup effectiveness of a vapor extraction system (VES) in extracting chlorinated hydrocarbons and petroleum-based hydrocarbons (mineral spirits) from the unsaturated zone. The statistical analysis of soil concentration data to evaluate the VES remediation success is described. The site is a former electronics refurbishing facility in southern California; soil contamination from organic solvents was found mainly in five areas (Area A through E) beneath two buildings. The evaluation begins with a brief description of the site background, discusses the statistical approach, and presents conclusions

Assessing breeding potential of peregrine falcons based on chlorinated hydrocarbon concentrations in prey

Energy Technology Data Exchange (ETDEWEB)

Elliott, J.E. [Canadian Wildlife Service, Pacific Wildlife Research Centre, 5421 Robertson Rd., RR no. 1, Delta, British Columbia, V4K 3N2 (Canada)]. E-mail: john.elliott@ec.gc.ca; Miller, M.J. [Iolaire Ecological Consulting, 7899 Thrasher St., Mission, British Columbia, V2V 5H3 (Canada); Wilson, L.K. [Canadian Wildlife Service, Pacific Wildlife Research Centre, 5421 Robertson Rd., RR no. 1, Delta, British Columbia, V4K 3N2 (Canada)

2005-03-01

Peregrine falcons (Falco peregrinus) now breed successfully in most areas of North America from which they were previously extirpated. The loss during the mid-part of the last century of many of the world's peregrine populations was largely a consequence of impaired reproduction caused by the effects of DDE on eggshell quality and embryo hatchability. Population recovery has been attributed to re-introduction efforts, coupled with regulatory restrictions on the use of organochlorine pesticides. Peregrines have not returned to breed in some areas, such as the Okanagan Valley of British Columbia. That region has been extensively planted in fruit orchards which were treated annually with DDT during the early 1950s to the 1970s. Ongoing contamination of avian species, including potential peregrine prey, inhabiting orchards has been documented. In response to an initiative to release peregrines around the city of Kelowna in the Okanagan Valley, we collected potential peregrine prey species and analyzed whole bodies for chlorinated hydrocarbon residues. We used a simple bioaccumulation model to predict concentrations of DDE in peregrine eggs using concentrations in prey and estimates of dietary makeup as input. Peregrines would be expected to breed successfully only if they fed on a diet primarily of doves. Feeding on as little as 10% of other species such as starlings, robins, gulls and magpies would produce DDE concentrations in peregrine eggs greater than the threshold of 15 mg/kg. We also estimated the critical concentration of DDE in total prey to be about 0.5 mg/kg, one half of the previous most conservative criterion for peregrine prey. Concentrations of dieldrin and PCBs in peregrine prey are less than suggested critical levels. - Based on the level of DDE contamination of prey items, it seems unlikely that peregrine falcons could breed successfully throughout most of the Okanagan Valley of British Columbia.

Characterization of Preferential Ground-Water Seepage From a Chlorinated Hydrocarbon-Contaminated Aquifer to West Branch Canal Creek, Aberdeen Proving Ground, Maryland, 2002-04

Science.gov (United States)

Majcher, Emily H.; Phelan, Daniel J.; Lorah, Michelle M.; McGinty, Angela L.

2007-01-01

Wetlands act as natural transition zones between ground water and surface water, characterized by the complex interdependency of hydrology, chemical and physical properties, and biotic effects. Although field and laboratory demonstrations have shown efficient natural attenuation processes in the non-seep wetland areas and stream bottom sediments of West Branch Canal Creek, chlorinated volatile organic compounds are present in a freshwater tidal creek at Aberdeen Proving Ground, Maryland. Volatile organic compound concentrations in surface water indicate that in some areas of the wetland, preferential flow paths or seeps allow transport of organic compounds from the contaminated sand aquifer to the overlying surface water without undergoing natural attenuation. From 2002 through 2004, the U.S. Geological Survey, in cooperation with the Environmental Conservation and Restoration Division of the U.S. Army Garrison, Aberdeen Proving Ground, characterized preferential ground-water seepage as part of an ongoing investigation of contaminant distribution and natural attenuation processes in wetlands at this site. Seep areas were discrete and spatially consistent during thermal infrared surveys in 2002, 2003, and 2004 throughout West Branch Canal Creek wetlands. In these seep areas, temperature measurements in shallow pore water and sediment more closely resembled those in ground water than those in nearby surface water. Generally, pore water in seep areas contaminated with chlorinated volatile organic compounds had lower methane and greater volatile organic compound concentrations than pore water in non-seep wetland sediments. The volatile organic compounds detected in shallow pore water in seeps were spatially similar to the dominant volatile organic compounds in the underlying Canal Creek aquifer, with both parent and anaerobic daughter compounds detected. Seep locations characterized as focused seeps contained the highest concentrations of chlorinated parent compounds

Factors affecting the distribution of hydrocarbon contaminants and hydrogeochemical parameters in a shallow sand aquifer

Science.gov (United States)

Lee, Jin-Yong; Cheon, Jeong-Yong; Lee, Kang-Kun; Lee, Seok-Young; Lee, Min-Hyo

2001-07-01

The distributions of hydrocarbon contaminants and hydrogeochemical parameters were investigated in a shallow sand aquifer highly contaminated with petroleum hydrocarbons leaked from solvent storage tanks. For these purposes, a variety of field investigations and studies were performed, which included installation of over 100 groundwater monitoring wells and piezometers at various depths, soil logging and analyses during well and piezometer installation, chemical analysis of groundwater, pump tests, and slug tests. Continuous water level monitoring at three selected wells using automatic data-logger and manual measuring at other wells were also conducted. Based on analyses of the various investigations and tests, a number of factors were identified to explain the distribution of the hydrocarbon contaminants and hydrogeochemical parameters. These factors include indigenous biodegradation, hydrostratigraphy, preliminary pump-and-treat remedy, recharge by rainfall, and subsequent water level fluctuation. The permeable sandy layer, in which the mean water table elevation is maintained, provided a dominant pathway for contaminant transport. The preliminary pump-and-treat action accelerated the movement of the hydrocarbon contaminants and affected the redox evolution pattern. Seasonal recharge by rain, together with indigenous biodegradation, played an important role in the natural attenuation of the petroleum hydrocarbons via mixing/dilution and biodegradation. The water level fluctuations redistributed the hydrocarbon contaminants by partitioning them into the soil and groundwater. The identified factors are not independent but closely inter-correlated.

Bioremediation of hydrocarbon and brine contaminated topsoil : annual report (1992-93)

International Nuclear Information System (INIS)

Danielson, R.M.

1996-01-01

This report presents the results of a study which examined the remediation of hydrocarbon and brine contaminated topsoil in a field-based bioreactor at a gas processing plant in Nevis, Alberta during 1992 and 1993. The hydrocarbon and brine contaminated topsoil was placed in the Bio-Reactor and treated for eleven months. Four treatments were applied to eight Bio-Reactor cells: (1) ambient temperature/no forced aeration, (2) ambient temperature/forced aeration, (3) optimum temperature/no forced aeration and (4) optimum temperature/forced aeration. The ninth cell was filled with 30 cm contaminated topsoil and maintained under optimum temperature/forced aeration. The contaminated topsoil was kept moist throughout the experiment by an automatic irrigation system. The contaminated topsoil in the heated cells lost 40 per cent of its original hydrocarbon content in one year; the soil in the non-heated cells lost between 25 and 29 per cent in the same period. Results showed that the Bio-Reactor offered an inexpensive means for promoting a natural process for degrading organic compounds by microorganisms in soil. Equally important, it is capable of handling the large volumes of waste produced by the oil and gas industry. 64 refs., 35 tabs., 46 figs

Application of novel activated carbon fiber solid-phase, microextraction to the analysis of chlorinated hydrocarbons in water by gas chromatography-mass spectrometry

International Nuclear Information System (INIS)

Sun Tonghua; Jia Jinping; Fang Nenghu; Wang Yalin

2005-01-01

This paper presents a study on the performance of activated carbon fiber (ACF) used as extraction fiber for solid-phase microextraction (SPME) and its application for analysis of chlorinated hydrocarbons in water. By means of evaluating scanning electron microscope (SEM) images, specific surface area, pore volume, pore distribution, and properties of adsorption and desorption, the optimal active concentration of phosphoric acid has been determined. Coupled with gas chromatograph-mass spectrometry (GC-MS), ACF-SPME is suitable for determination chlorinated hydrocarbons in water with headspace. Experimental parameters such as adsorption and desorption conditions were studied. The optimized method has an acceptable linearity, good precision, with R.S.D. values <10% for each compound. Compared with commercial fibers, ACF has many advantages such as better resistance to organic solvents, better endurance to high temperature and longer lifetime

Exploration of hydrocarbon degrading bacteria on soils contaminated by crude oil from South Sumatera

Directory of Open Access Journals (Sweden)

A. Napoleon

2014-07-01

Full Text Available The goal of this research was to explore hydrocarbon degrading bacteria on crude oil contaminated soil with potential to degrade hydrocarbon in oil pollutant. The research started by early August 2013 till January 2014. Soil sampling for this research was taken on several places with contaminated soil location such as Benakat, Rimau, and Pengabuan all of it located in South Sumatera. Conclusion from this research Isolates obtained from three (3 sites of contaminated soil and treated using SBS medium were Bacillus cereus, Pseudomonas aeruginosa, Klebsiella pnumoniae, Streptococcus beta hemolisa, Proteus mirabilis, Staphylococcus epidermis and Acinotobacter calcoaceticus. Isolates that survived on 300 ppm of hydrocarbon concentration were Bacillus cereus, Pseudomonas aeruginosa and Acinetobacter cakciaceticus Selected isolates posses the ability to degrade hydrocarbon by breaking hydrocarbon substance as the energy source to support isolates existence up to 1,67 TPH level. Based on results accomplish by this research, we urge for further research involving the capacity of isolates to degrade wide variety of hydrocarbon substance and more to develop the potential of these bacteria for bioremediation.

Multi-isotope (carbon and chlorine) analysis for fingerprinting and site characterization at a fractured bedrock aquifer contaminated by chlorinated ethenes

DEFF Research Database (Denmark)

Palau, Jordi; Marchesi, Massimo; Chambon, Julie Claire Claudia

2014-01-01

is located in Spain with contamination resulting in groundwater concentrations of up to 50 mg/L of trichloroethene (TCE), the most abundant chlorinated ethene, and 7 mg/L of tetrachloroethene (PCE). The potential sources of contamination including abandoned barrels, an underground tank, and a disposal lagoon......, showed a wide range in δ13C values from − 15.6 to − 40.5‰ for TCE and from − 18.5 to − 32.4‰ for PCE, allowing the use of isotope fingerprinting for tracing of the origin and migration of these contaminants in the aquifer. In contrast, there is no difference between the δ37Cl values for TCE...

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

In situ bioremediation of petroleum hydrocarbons and chlorinated hydrocarbons: Three case studies

International Nuclear Information System (INIS)

Bost, R.C.; Perry, R.G.; Barber, T.

1997-01-01

In situ biodegradation of organic contaminants is one of the most cost-effective means of site remediation. This method has proven successful in soils, ground water, and slurries. Bacteria capable of degrading organic contaminants within an aquifer include many species from a wide spectrum of genera, e.g. Pseudomonas, Corynebacterium, Bacillus, etc. In most cases, a mixture of bacterial strains is required to completely oxidize a complex organic contaminant. Each strain of an organism may target a specific compound, working together with other organisms to ultimately degrade each intermediate until complete degradation, also known as mineralization, occurs. One or more of the following mechanisms are utilized by bacteria for organic chemical degradation: (1) aerobic, (2) anaerobic, and (3) co-metabolic. During aerobic oxidation of organic chemicals, bacteria utilize the pollutant as an electron and hydrogen source and oxygen acts as the electron and hydrogen acceptor, resulting in water. As the bacterial enzymes cleave the compound, oxidized products are produced along with energy for the reaction to proceed. This is the most rapid and widely utilized mechanism. Dehalogenation occurs under aerobic, or perhaps more often, under anoxic conditions. This process occurs in the presence of alternate electron acceptors and replaces chlorine with hydrogen. The mechanism of co-metabolism can be aerobic or anaerobic, but is more often aerobic. This process requires a separate energy source for the bacterial cell because the pollutant is not utilized as an energy source. The role of bioremediation in site remediation is demonstrated below by three case studies: (1) a refinery, (2) a municipal landfill and (3) a pesticide formulation plant

Petroleum Hydrocarbons Contamination Profile of Ochani Stream in ...

African Journals Online (AJOL)

Petroleum hydrocarbon contamination profile, heavy metals and some physicochemical parameters were investigated in Ochani Stream site in Ejamah Ebubu, Eleme Local Government Area of Rivers State. The results show that a major crude oil spillage occurred at Ejamah Ebubu, Rivers State, Nigeria approximately 30 ...

In situ vadose zone bioremediation of soil contaminated with nonvolatile hydrocarbons

International Nuclear Information System (INIS)

Hogg, D.S.; Burden, R.J.; Riddell, P.J.

1992-01-01

In situ bioremediation has been successfully carried out on petroleum hydrocarbon-contaminated soil at a decommissioned bulk storage terminal in New Zealand. The site soils were contaminated mainly with diesel fuel and spent oil at concentrations ranging up to 95,000 mg/kg of total recoverable petroleum hydrocarbons. The in situ remediation system combines an enhanced bioremediation with vapor extraction and is installed almost entirely below grade, thereby allowing above ground activities to continue unimpeded. Laboratory-scale feasibility testing indicated that although appreciable volatilization of low molecular weight components would occur initially, biodegradation would be the primary mechanism by which contaminated soil would be remediated. During the remedial design phase, preliminary field testing was conducted to evaluate the optimum spacing for extraction wells and inlet vents. A pilot-scale system was installed in a 15-m by 35-m area of the site in June 1989 and operated for approximately 1 year. Soil monitoring performed approximately every 3 months indicated an overall reduction in soil petroleum hydrocarbon concentrations of 87% for the period from June 1989 to May 1991

The role of chlorine and additives of PVC-plastic in combustion

International Nuclear Information System (INIS)

Mattila, H.

1991-01-01

The PVC differs from other common plastics due to the chlorine content. As the PVC is combusted, the chlorine is released mainly as hydrogen chloride. The content of chlorinated hydrocarbons is small, but these can also contain polychlorinated dibenzofuranes and dibenzodioxines, which are extremely poisonous. The aim of this study was to find out, what is the portion of PVC combustion in total emission of chlorinated hydrocarbons. Additionally, the amounts chlorine coming into combustion process with ordinary fuels have been estimated, and they are compared with the amounts of PVC. The chloride content of municipal wastes vary in between 0.4-0.9 %. The portion of plastics is about 30 % of the total, and the rest being from paper, food , wood and garden wastes an textiles. Both organic and inorganic chlorine form gaseous hydrogen chlorid in combustion processes. HCl can then react with oxygen and produce caseous chlorine. This can react with unreacted carbon of the smoke and produce different kinds of chlorinated hydrocarbons. The portion of PVC of the chlorine going into combustion in Finland has been estimated to be about 1-2 %. Combustion tests were made using coal and bark and plastic waste as additional fuel. It was noticed that addition of plastic decreased the amount of polyaromatic hydrocarbons in the smoke. Chlorinated dioxins and furans occurred a little less in the gases of combustion of plastic mixtures not containing PVC than in reference tests, but they increased when PVC containing plastic mixture was combusted, but more chlorinated dioxins and furans were absorbed into fly ash, so the emissions remained almost the same

Selection of biosurfactan/bioemulsifier-producing bacteria from hydrocarbon-contaminated soil

Directory of Open Access Journals (Sweden)

Sabina Viramontes-Ramos

2010-10-01

Full Text Available Petroleum-derived hydrocarbons are among the most persistent soil contaminants, and some hydrocarbon-degrading microorganisms can produce biosurfactants to increase bioavailability and degradation. The aim of this work was to identify biosurfactant-producing bacterial strains isolated from hydrocarbon-contaminated sites, and to evaluate their biosurfactant properties. The drop-collapse method and minimal agar added with a layer of combustoleo were used for screening, and positive strains were grown in liquid medium, and surface tension and emulsification index were determined in cell-free supernantant and cell suspension. A total of 324 bacterial strains were tested, and 17 were positive for the drop-collapse and hydrocarbon-layer agar methods. Most of the strains were Pseudomonas, except for three strains (Acinetobacter, Bacillus, Rhodococcus. Surface tension was similar in cell-free and cell suspension measurements, with values in the range of 58 to 26 (mN/m, and all formed stable emulsions with motor oil (76-93% E24. Considering the variety of molecular structures among microbial biosurfactants, they have different chemical properties that can be exploited commercially, for applications as diverse as bioremediation or degradable detergents.

Diatom, cyanobacterial and microbial mats as indicators of hydrocarbon contaminated Arctic streams and waters

Energy Technology Data Exchange (ETDEWEB)

Ziervogel, H.; Selann, J.; Adeney, B. [EBA Engineering Consultants Ltd., Edmonton, AB (Canada); Nelson, J.A. [J.B. Services, Sarnia, ON (Canada); Murdock, E. [Nunavut Power, Iqaluit (Canada)

2003-07-01

An environmental assessment conducted at Repulse Bay, Nunavut in the summer of 2001 revealed a recent diesel spill flowing from the groundwater into a creek. The spill had not been reported. When Arctic surface waters mix with hydrocarbon impacted groundwater and sediments, distinctive mats of diatom, cyanobacteria and other bacteria are formed. These mats have the potential for phytoremediation of hydrocarbons. This paper explained the apparent dominance of mats in contaminated Arctic waters and why they promote biodegradation of hydrocarbons. Hydrocarbon-contaminated soils and groundwater are generally anaerobic. The higher dissolved carbon dioxide in polluted soils and groundwater can benefit photosynthetic cyanobacteria and diatom found in oligotrophic, lower alkalinity Arctic waters. The anaerobic and aerobic bacteria can potentially take advantage of the hydrogen substrate and the nitrogen fixing abilities of the cyanobacteria. Zooplankton predators may be killed off by the toxicity of the polluted groundwater. The paper provides examples where a microbial mat reduced the sulfate content of a hydrocarbon-impacted Arctic stream by 100 ppm, and where a pond covered in a benthic microbial mat showed no evidence of hydrocarbons in the water overlying sediments contaminated with hydrocarbons at concentrations measured at 30,000 ppm. 19 refs., 3 tabs., 8 figs.

Multi-isotope (carbon and chlorine) analysis for fingerprinting and site characterization at a fractured bedrock aquifer contaminated by chlorinated ethenes

Energy Technology Data Exchange (ETDEWEB)

Palau, Jordi, E-mail: jordi.palau@unine.ch [Departament de Cristal.lografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona, Martí i Franquès, s/n 08028 Barcelona (Spain); Marchesi, Massimo [Departament de Cristal.lografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona, Martí i Franquès, s/n 08028 Barcelona (Spain); Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Chambon, Julie C.C. [Department of Environmental Engineering, Technical University of Denmark, 2800 Lyngby (Denmark); Aravena, Ramon [Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Canals, Àngels [Departament de Cristal.lografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona, Martí i Franquès, s/n 08028 Barcelona (Spain); Binning, Philip J.; Bjerg, Poul L. [Department of Environmental Engineering, Technical University of Denmark, 2800 Lyngby (Denmark); Otero, Neus; Soler, Albert [Departament de Cristal.lografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona, Martí i Franquès, s/n 08028 Barcelona (Spain)

2014-03-01

The use of compound specific multi-isotope approach (C and Cl) in the characterization of a chlorinated ethenes contaminated fractured aquifer allows the identification of several sources and contaminant plumes, as well as the occurrence of biodegradation and mixing processes. The study site is located in Spain with contamination resulting in groundwater concentrations of up to 50 mg/L of trichloroethene (TCE), the most abundant chlorinated ethene, and 7 mg/L of tetrachloroethene (PCE). The potential sources of contamination including abandoned barrels, an underground tank, and a disposal lagoon, showed a wide range in δ{sup 13}C values from − 15.6 to − 40.5‰ for TCE and from − 18.5 to − 32.4‰ for PCE, allowing the use of isotope fingerprinting for tracing of the origin and migration of these contaminants in the aquifer. In contrast, there is no difference between the δ{sup 37}Cl values for TCE in the contaminant sources, ranging from + 0.53 to + 0.66‰. Variations of δ{sup 37}Cl and δ{sup 13}C in the different contaminant plumes were used to investigate the role of biodegradation in groundwater. Moreover, the isotopic data were incorporated into a reactive transport model for determination of whether the isotope pattern observed downstream from the tank's source could be explained by the simultaneous effect of mixing and biodegradation. The results demonstrate that a multi-isotope approach is a valuable tool for characterization of complex sites such as fractured bedrock aquifer contaminated by multiple sources, providing important information which can be used by consultants and site managers to prioritize and design more successful remediation strategies. - Highlights: • Origin and fate of CAHs in groundwater by means of multi CSIA ({sup 13}C,{sup 35}Cl) survey • Innovative/new approach tested in a fractured bedrock site • Differentiation of distinct CAH sources • Biodegradation and source mixing recognition in the aquifer.

Multi-isotope (carbon and chlorine) analysis for fingerprinting and site characterization at a fractured bedrock aquifer contaminated by chlorinated ethenes

International Nuclear Information System (INIS)

Palau, Jordi; Marchesi, Massimo; Chambon, Julie C.C.; Aravena, Ramon; Canals, Àngels; Binning, Philip J.; Bjerg, Poul L.; Otero, Neus; Soler, Albert

2014-01-01

The use of compound specific multi-isotope approach (C and Cl) in the characterization of a chlorinated ethenes contaminated fractured aquifer allows the identification of several sources and contaminant plumes, as well as the occurrence of biodegradation and mixing processes. The study site is located in Spain with contamination resulting in groundwater concentrations of up to 50 mg/L of trichloroethene (TCE), the most abundant chlorinated ethene, and 7 mg/L of tetrachloroethene (PCE). The potential sources of contamination including abandoned barrels, an underground tank, and a disposal lagoon, showed a wide range in δ 13 C values from − 15.6 to − 40.5‰ for TCE and from − 18.5 to − 32.4‰ for PCE, allowing the use of isotope fingerprinting for tracing of the origin and migration of these contaminants in the aquifer. In contrast, there is no difference between the δ 37 Cl values for TCE in the contaminant sources, ranging from + 0.53 to + 0.66‰. Variations of δ 37 Cl and δ 13 C in the different contaminant plumes were used to investigate the role of biodegradation in groundwater. Moreover, the isotopic data were incorporated into a reactive transport model for determination of whether the isotope pattern observed downstream from the tank's source could be explained by the simultaneous effect of mixing and biodegradation. The results demonstrate that a multi-isotope approach is a valuable tool for characterization of complex sites such as fractured bedrock aquifer contaminated by multiple sources, providing important information which can be used by consultants and site managers to prioritize and design more successful remediation strategies. - Highlights: • Origin and fate of CAHs in groundwater by means of multi CSIA ( 13 C, 35 Cl) survey • Innovative/new approach tested in a fractured bedrock site • Differentiation of distinct CAH sources • Biodegradation and source mixing recognition in the aquifer

Exploration of Hydrocarbon Degrading Bacteria on Soils Contaminated by Crude Oil From South Sumatera

OpenAIRE

Napoleon, A; Probowati, D S

2014-01-01

The goal of this research was to explore hydrocarbon degrading bacteria on crude oil contaminated soil with potential to degrade hydrocarbon in oil pollutant. The research started by early August 2013 till January 2014. Soil sampling for this research was taken on several places with contaminated soil location such as Benakat, Rimau, and Pengabuan all of it located in South Sumatera. Conclusion from this research Isolates obtained from three (3) sites of contaminated soil and treated using SB...

Analysis of dechlorination kinetics of chlorinated aliphatic hydrocarbons by Fe(II) in cement slurries

Energy Technology Data Exchange (ETDEWEB)

Jung, Bahngmi [Department of Earth and Environmental Sciences, Wright State University, Dayton, OH 45435-0001 (United States)], E-mail: jung.bahngmi@gmail.com; Batchelor, Bill [Department of Civil Engineering, Texas A and M University, College Station, TX 77843-3136 (United States)

2008-03-21

Degradative solidification/stabilization with ferrous iron (DS/S-Fe(II)) has been found to be effective in degrading a number of chlorinated aliphatic hydrocarbons including 1,1,1-trichloroethane (1,1,1-TCA), 1,1,2,2-tetrachloroethane (1,1,2,2-TeCA), tetrachloroethylene (PCE), trichloroethylene (TCE), 1,1-dichloroethylene (1,1-DCE), vinyl chloride (VC), carbon tetrachloride (CT) and chloroform (CF). Previous studies have characterized degradation kinetics in DS/S-Fe(II) systems as affected by Fe(II) dose, pH and initial target organic concentration. The goal of this study is to investigate the importance of various chemical properties on degradation kinetics of DS/S-Fe(II). This was accomplished by first measuring rate constants for degradation of 1,1,1-TCA, 1,1,2,2-TeCA and 1,2-dichloroethane (1,2-DCA) in individual batch experiments. Rate constants developed in these experiments and those obtained from the literature were related to thermodynamic parameters including one-electron reduction potential, two-electron reduction potential, bond dissociation energy and lowest unoccupied molecular orbital energies. Degradation kinetics by Fe(II) in cement slurries were generally represented by a pseudo-first-order rate law. The results showed that the rate constants for chlorinated methanes (e.g. CT, CF) and chlorinated ethanes (e.g. 1,1,1-TCA) were higher than those for chlorinated ethylenes (e.g. PCE, TCE, 1,1-DCE and VC) under similar experimental conditions. The log of the pseudo-first-order rate constant (k) was found to correlate better with lowest unoccupied molecular orbital energies (E{sub LUMO}) (R{sup 2} = 0.874) than with other thermodynamic parameter descriptors.

Microbial Diversity and Bioremediation of a Hydrocarbon-Contaminated Aquifer (Vega Baja, Puerto Rico

Directory of Open Access Journals (Sweden)

Arturo A. Massol-Deyá

2006-09-01

Full Text Available Hydrocarbon contamination of groundwater resources has become a major environmental and human health concern in many parts of the world. Our objectives were to employ both culture and culture-independent techniques to characterize the dynamics of microbial community structure within a fluidized bed reactor used to bioremediate a diesel-contaminated groundwater in a tropical environment. Under normal operating conditions, 97 to 99% of total hydrocarbons were removed with only 14 min hydraulic retention time. Over 25 different cultures were isolated from the treatment unit (96% which utilized diesel constituents as sole carbon source. Approximately 20% of the isolates were also capable of complete denitrification to nitrogen gas. Sequence analysis of 16S rDNA demonstrated ample diversity with most belonging to the ∝, β and γ subdivision of the Proteobacteria, Bacilli, and Actinobacteria groups. Moreover, the genetic constitution of the microbial community was examined at multiple time points with a Functional Gene Array (FGA containing over 12,000 probes for genes involved in organic degradation and major biogeochemical cycles. Total community DNA was extracted and amplified using an isothermal φ29 polymerase-based technique, labeled with Cy5 dye, and hybridized to the arrays in 50% formimide overnight at 50°C. Cluster analysis revealed comparable profiles over the course of treatment suggesting the early selection of a very stable microbial community. A total of 270 genes for organic contaminant degradation (including naphthalene, toluene [aerobic and anaerobic], octane, biphenyl, pyrene, xylene, phenanthrene, and benzene; and 333 genes involved in metabolic activities (nitrite and nitrous oxide reductases [nirS, nirK, and nosZ], dissimilatory sulfite reductases [dsrAB], potential metal reducing C-type cytochromes, and methane monooxygenase [pmoA] were repeatedly detected. Genes for degradation of MTBE

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

Decontamination of hydrocarbon contaminated soil

International Nuclear Information System (INIS)

Smith, A.J.

1991-01-01

This patent describes the method of treating hydrocarbon contaminated soil. It comprises forming the soil into a flowing particulate stream, forming an aqueous liquid mixture of water and treating substance that reacts with hydrocarbon to form CO 2 and water, dispersing the liquid mixture into the particulate soil stream to wet the particulate, allowing the substance to react with the wetted soil particulate to thereby form CO 2 and water, thereby the resultant soil is beneficially treated, the stream being freely projected to dwell at a level and then fall, and the dispersing includes spraying the liquid mixture into the projected stream at the dwell, the substance consisting of natural bacteria, and at a concentration level in the mixture of between 100 to 3,000 PPM of bacteria to water, the soil forming step including impacting the soil to reduce it to particles less than about 1 inches in cross dimension, and including forming the wetting particulate into a first layer on a surface to allow the substance to react

Chlorine isotope investigation of natural attenuation of trichloroethene in an aerobic aquifer

International Nuclear Information System (INIS)

Sturchio, N.C.; Heraty, L.J.; Huang, L.; Holt, B.D.; Abrajano, T.A. Jr.; Clausen, J.L.

1998-01-01

Natural attenuation of chlorinated aliphatic hydrocarbons (CAHs) can be an important mechanism for groundwater remediation. It is difficult to determine the effectiveness of natural CAH attenuation from chemical analyses of groundwater samples because mixing, dispersion, and secondary reactions can mask the chemical evidence of attenuation. In this paper, the authors explore the application of stable chlorine isotope ratio measurements as a new tool for evaluating natural attenuation of CAHs. They report stable isotope ratios of chlorine in both trichloroethene (TCE) and inorganic chloride in groundwater from an aerobic aquifer beneath an extensively contaminated industrial site, the Paducah Gaseous Diffusion Plant in western Kentucky. Variations in the concentrations and chlorine isotope ratios of TCE and chloride in the groundwater are consistent with those expected from natural attenuation. These data support a model in which partial TCE degradation occurred in relatively impermeable, clay-rich sediments above the aquifer, and little or no further degradation of TCE occurred within the aquifer. A record of changing conditions within the TCE source area can be inferred from the spatial variation of chlorine isotope ratios for TCE and chloride within the plume

Studies concerning thermodynamics and kinetics of the absorption of halogenated hydrocarbons relevant to environment

International Nuclear Information System (INIS)

Weisweiler, W.; Eidam, K.; Winterbauer, H.

1993-07-01

In the context of the research project the scrubbing of air contaminated by peculiar volatile organic compounds was investigated using the absorption technique by means of high boiling organics as washing liquids. Eight chlorinated hydrocarbons well known from technical processes were chosen to be representative for the volatile organic compounds. Eleven absorption media were selected on the basis of their physical properties. For the determination of the solubility data of the absorption media due to chlorinated hydrocarbons, nitrogen as well as a mixture of nitrogen and oxygen were used as carrier gas. The influence of the dipole moment of the absorption media on the amount of solubility - expressed as enrichment factor - was studied, too. Concerning the technical application, the thermostability and the stability against diluted inorganic acids were studied as well. (orig.). 56 figs., 8 tabs., 63 refs [de

Prediction of ecotoxicity of hydrocarbon-contaminated soils using physicochemical parameters

Energy Technology Data Exchange (ETDEWEB)

Wong, D.C.L.; Chai, E.Y.; Chu, K.K.; Dorn, P.B.

1999-11-01

The physicochemical properties of eight hydrocarbon-contaminated soils were used to predict toxicity to earthworms (Eisenia fetida) and plants. The toxicity of these preremediated soils was assessed using earthworm avoidance, survival, and reproduction and seed germination and root growth in four plant species. No-observed-effect and 25% inhibitory concentrations were determined from the earthworm and plant assays. Physical property measurements and metals analyses of the soils were conducted. Hydrocarbon contamination was characterized by total petroleum hydrocarbons, oil and grease, and GC boiling-point distribution. Univariate and multivariate statistical methods were used to examine relationships between physical and chemical properties and biological endpoints. Soil groupings based on physicochemical properties and toxicity from cluster and principal component analyses were generally similar. Correlation analysis identified a number of significant relationships between soil parameters and toxicity that were used in univariate model development. Total petroleum hydrocarbons by gas chromatography and polars were identified as predictors of earthworm avoidance and survival and seed germination, explaining 65 to 75% of the variation in the data. Asphaltenes also explained 83% of the variation in seed germination. Gravimetric total petroleum hydrocarbons explained 40% of the variation in earthworm reproduction, whereas 43% of the variation in plant root growth was explained by asphaltenes. Multivariate one-component partial least squares models, which identified predictors similar to those identified by the univariate models, were also developed for worm avoidance and survival and seed germination and had predictive powers of 42 and 29%, respectively.

Modeling potential migration of petroleum hydrocarbons from a mixed-waste disposal site in the vadose zone

International Nuclear Information System (INIS)

Rawson, S.A.; Walton, J.C.; Baca, R.G.

1989-01-01

Environmental monitoring of a mixed-waste disposal site at the Idaho National Engineering Laboratory has confirmed release and migration into the vadose zone of: (1) chlorinated hydrocarbons in the vapor phase and (2) trace levels of certain transuranic elements. The finding has prompted an evaluation of the potential role of waste petroleum hydrocarbons in mediating or influencing contaminant migration from the disposal site. Disposal records indicate that a large volume of machine oil contaminated with transuranic isotopes was disposed at the site along with the chlorinated solvents and other radioactive wastes. A multiphase flow model was used to assess the possible extent of oil and vapor movement through the 177 m thick vadose zone. One dimensional simulations were performed to estimate the vertical distribution of the vapor phase, the aqueous phase, and immiscible free liquid as a function of time. The simulations indicate that the oil may migrate slowly through the vadose zone, to potentially significant depths. Calculated transport rates support the following ranking with regard to relative mobility: vapor phase > aqueous phase > free liquid. 21 refs., 7 figs., 2 tabs

IN SITU DESTRUCTION OF CHLORINATED HYDROCARBON COMPOUNDS IN GROUNDWATER USING CATALYTIC REDUCTIVE REDUCTIVE DEHALOGENATION IN A REACTIVE WELL: TESTING AND OPERATIONAL EXPERIENCES. (R825421)

Science.gov (United States)

A groundwater treatment technology based on catalytic reductive dehalogenation has been developed to efficiently destroy chlorinated hydrocarbons in situ using a reactive well approach. The treatment process utilizes dissolved H2 as an electron donor, in...

Biological Activity Assessment in Mexican Tropical Soils with Different Hydrocarbon Contamination Histories.

Science.gov (United States)

Riveroll-Larios, Jessica; Escalante-Espinosa, Erika; Fócil-Monterrubio, Reyna L; Díaz-Ramírez, Ildefonso J

The use of soil health indicators linked to microbial activities, such as key enzymes and respirometric profiles, helps assess the natural attenuation potential of soils contaminated with hydrocarbons. In this study, the intrinsic physicochemical characteristics, biological activity and biodegradation potential were recorded for two soils with different contamination histories (>5 years and soil samples. Soil suspensions were tested as microbial inocula in biodegradation potential assays using contaminated perlite as an inert support. The basal respiratory rate of the recently contaminated soil was 15-38 mg C-CO 2  kg -1 h -1 , while the weathered soil presented a greater basal mineralisation capacity of 55-70 mg C-CO 2 kg -1 h -1 . The basal levels of lipase and dehydrogenase were significantly greater than those recorded in non-contaminated soils (551 ± 21 μg pNP g -1 ). Regarding the biodegradation potential assessment, the lipase (1000-3000 μg pNP g -1 of perlite) and dehydrogenase (~3000 μg INF g -1 of perlite) activities in the inoculum of the recently contaminated soil were greater than those recorded in the inoculum of the weathered soil. This was correlated with a high mineralisation rate (~30 mg C-CO 2 kg -1 h -1 ) in the recently contaminated soil and a reduction in hydrocarbon concentration (~30 %). The combination of an inert support and enzymatic and respirometric analyses made it possible to detect the different biodegradation capacities of the studied inocula and the natural attenuation potential of a recently contaminated soil at high hydrocarbon concentrations.

Earthworm Comet Assay for Assessing the Risk of Weathered Petroleum Hydrocarbon Contaminated Soils: Need to Look Further than Target Contaminants.

Science.gov (United States)

Ramadass, Kavitha; Palanisami, Thavamani; Smith, Euan; Mayilswami, Srinithi; Megharaj, Mallavarapu; Naidu, Ravi

2016-11-01

Earthworm toxicity assays contribute to ecological risk assessment and consequently standard toxicological endpoints, such as mortality and reproduction, are regularly estimated. These endpoints are not enough to better understand the mechanism of toxic pollutants. We employed an additional endpoint in the earthworm Eisenia andrei to estimate the pollutant-induced stress. In this study, comet assay was used as an additional endpoint to evaluate the genotoxicity of weathered hydrocarbon contaminated soils containing 520 to 1450 mg hydrocarbons kg -1 soil. Results showed that significantly higher DNA damage levels (two to sixfold higher) in earthworms exposed to hydrocarbon impacted soils. Interestingly, hydrocarbons levels in the tested soils were well below site-specific screening guideline values. In order to explore the reasons for observed toxicity, the contaminated soils were leached with rainwater and subjected to earthworm tests, including the comet assay, which showed no DNA damage. Soluble hydrocarbon fractions were not found originally in the soils and hence no hydrocarbons leached out during soil leaching. The soil leachate's Electrical Conductivity (EC) decreased from an average of 1665 ± 147 to 204 ± 20 µS cm -1 . Decreased EC is due to the loss of sodium, magnesium, calcium, and sulphate. The leachate experiment demonstrated that elevated salinity might cause the toxicity and not the weathered hydrocarbons. Soil leaching removed the toxicity, which is substantiated by the comet assay and soil leachate analysis data. The implication is that earthworm comet assay can be included in future eco (geno) toxicology studies to assess accurately the risk of contaminated soils.

Molecular mechanisms in the pyrolysis of unsaturated chlorinated hydrocarbons: formation of benzene rings. 1. Quantum chemical studies.

Science.gov (United States)

McIntosh, Grant J; Russell, Douglas K

2013-05-23

Analogues of important aromatic growth mechanisms in hydrocarbon pyrolysis and combustion systems are extended to chlorinated systems. We consider the addition of C2Cl2 to both C4Cl3 and C4Cl5 radicals at the M06-2X/6-311+G(3df,3p)//B3LYP/6-31G(d) level of theory, and we demonstrate that these reaction systems have much in common with those of nonchlorinated species. In particular, we find that these radicals appear to lead preferentially to fulvenes, and not to the observed aromatic products, as is found in nonchlorinated systems. We have therefore also considered nonradical C4/C2 channels by way of Diels-Alder cyclization of C4Cl4/C2Cl2 and C4H2Cl2/C2HCl pairs to describe aromatic formation. While the latter pair readily leads to the formation of partially chlorinated benzenes, the fully chlorinated congeners are sterically prohibited from ring closing directly; this leads to a series of novel rearrangement processes which predict the formation of hexachloro-1,5-diene-3-yne, in addition to hexachlorobenzene, in good agreement with experiment. This suggests, for the first time, that facile nonradical routes to aromatic formation are operative in partially and fully chlorinated pyrolysis and combustion systems.

Assessing the Impact of Chlorinated-Solvent Sites on Metropolitan Groundwater Resources

OpenAIRE

Brusseau, Mark L.; Narter, Matthew

2013-01-01

Chlorinated-solvent compounds are among the most common groundwater contaminants in the U.S.A. The majority of the many sites contaminated by chlorinated-solvent compounds are located in metropolitan areas, and most such areas have one or more chlorinated-solvent contaminated sites. Thus, contamination of groundwater by chlorinated-solvent compounds may pose a potential risk to the sustainability of potable water supplies for many metropolitan areas. The impact of chlorinated-solvent sites on...

Bioremediation of hydrocarbon contaminated-oil field drill-cuttings ...

African Journals Online (AJOL)

The effectiveness of 2 bacterial isolates (Bacillus subtilis and Pseudomonas aeruginosa) in the restoration of oil-field drill-cuttings contaminated with polycyclic aromatic hydrocarbons (PAHs) was studied. A mixture of 4 kg of the drill-cuttings and 0.67 kg of top-soil were charged into triplicate plastic reactors labeled A1 to A3, ...

Influence of in situ steam formation by radio frequency heating on thermodesorption of hydrocarbons from contaminated soil.

Science.gov (United States)

Roland, Ulf; Bergmann, Sabine; Holzer, Frank; Kopinke, Frank-Dieter

2010-12-15

Thermal desorption of a wide spectrum of organic contaminants, initiated by radio frequency (RF) heating, was studied at laboratory and pilot-plant scales for an artificially contaminated soil and for an originally contaminated soil from an industrial site. Up to 100 °C, moderate desorption rates were observed for light aromatics such as toluene, chlorobenzene, and ethylbenzene. Desorption of the less volatile contaminants was greatly enhanced above 100 °C, when fast evaporation of soil-water produced steam for hydrocarbon stripping (steam-distillation, desorption rates increased by more than 1 order of magnitude). For hydrocarbons with low water solubility (e.g., aliphatic hydrocarbons), the temperature increase above 100 °C after desiccation of soil again led to a significant increase of the removal rates, thus showing the impact of hydrocarbon partial pressure. RF heating was shown to be an appropriate option for thermally enhanced soil vapor extraction, leading to efficient cleaning of contaminated soils.

Pyrolytic Treatment and Fertility Enhancement of Soils Contaminated with Heavy Hydrocarbons.

Science.gov (United States)

Vidonish, Julia E; Zygourakis, Kyriacos; Masiello, Caroline A; Gao, Xiaodong; Mathieu, Jacques; Alvarez, Pedro J J

2016-03-01

Pyrolysis of contaminated soils at 420 °C converted recalcitrant heavy hydrocarbons into "char" (a carbonaceous material similar to petroleum coke) and enhanced soil fertility. Pyrolytic treatment reduced total petroleum hydrocarbons (TPH) to below regulatory standards (typically hydrocarbons (PAHs) was not observed, with post-pyrolysis levels well below applicable standards. Plant growth studies showed a higher biomass production of Arabidopsis thaliana and Lactuca sativa (Simpson black-seeded lettuce) (80-900% heavier) in pyrolyzed soils than in contaminated or incinerated soils. Elemental analysis showed that pyrolyzed soils contained more carbon than incinerated soils (1.4-3.2% versus 0.3-0.4%). The stark color differences between pyrolyzed and incinerated soils suggest that the carbonaceous material produced via pyrolysis was dispersed in the form of a layer coating the soil particles. Overall, these results suggest that soil pyrolysis could be a viable thermal treatment to quickly remediate soils impacted by weathered oil while improving soil fertility, potentially enhancing revegetation.

Release of polyaromatic hydrocarbons from coal tar contaminated soils

International Nuclear Information System (INIS)

Priddy, N.D.; Lee, L.S.

1996-01-01

A variety of process wastes generated from manufactured gas production (MGP) have contaminated soils and groundwater at production and disposal sites. Coal tar, consisting of a complex mixture of hydrocarbons present as a nonaqueous phase liquid, makes up a large portion of MGP wastes. Of the compounds in coal tar, polyaromatic hydrocarbons (PAHs) are the major constituents of environmental concern due to their potential mutagenic and carcinogenic hazards. Characterization of the release of PAHs from the waste-soil matrix is essential to quantifying long-term environmental impacts in soils and groundwater. Currently, conservative estimates for the release of PAHs to the groundwater are made assuming equilibrium conditions and using relationships derived from artificially contaminated soils. Preliminary work suggests that aged coal tar contaminated soils have much lower rates of desorption and a greater affinity for retaining organic contaminants. To obtain better estimates of desorption rates, the release of PAHs from a coal tar soil was investigated using a flow-interruption, miscible displacement technique. Methanol/water solutions were employed to enhance PAH concentrations above limits of detection. For each methanol/water solution employed, a series of flow interrupts of varying times was invoked. Release rates from each methanol/water solution were estimated from the increase in concentration with duration of flow interruption. Aqueous-phase release rates were then estimated by extrapolation using a log-linear cosolvency model

Bacterial Endophytes Isolated from Plants in Natural Oil Seep Soils with Chronic Hydrocarbon Contamination

OpenAIRE

Lumactud, Rhea; Shen, Shu Yi; Lau, Mimas; Fulthorpe, Roberta

2016-01-01

The bacterial endophytic communities of four plants growing abundantly in soils highly contaminated by hydrocarbons were analyzed through culturable and and culture-independent means. Given their tolerance to the high levels of petroleum contamination at our study site, we sought evidence that Achillea millefolium, Solidago canadensis, Trifolium aureum and Dactylis glomerata support high levels of hydrocarbon degrading endophytes. A total of 190 isolates were isolated from four plant species....

Phytoremediation of petroleum hydrocarbon-contaminated saline-alkali soil by wild ornamental Iridaceae species.

Science.gov (United States)

Cheng, Lijuan; Wang, Yanan; Cai, Zhang; Liu, Jie; Yu, Binbin; Zhou, Qixing

2017-03-04

As a green remediation technology, phytoremediation is becoming one of the most promising methods for treating petroleum hydrocarbons (PHCs)-contaminated soil. Pot culture experiments were conducted in this study to investigate phytoremediation potential of two representative Iridaceae species (Iris dichotoma Pall. and Iris lactea Pall.) in remediation of petroleum hydrocarbon-contaminated saline-alkali soil from the Dagang Oilfield in Tianjin, China. The results showed that I. lactea was more endurable to extremely high concentration of PHCs (about 40,000 mg/kg), with a relatively high degradation rate of 20.68%.The degradation rate of total petroleum hydrocarbons (TPHs) in soils contaminated with 10,000 and 20,000 mg/kg of PHCs was 30.79% and 19.36% by I. dichotoma, and 25.02% and 19.35% by I. lactea, respectively, which improved by 10-60% than the unplanted controls. The presence of I. dichotoma and I. lactea promoted degradation of PHCs fractions, among which saturates were more biodegradable than aromatics. Adaptive specialization was observed within the bacterial community. In conclusion, phytoremediation by I. dichotoma should be limited to soils contaminated with ≤20,000 mg/kg of PHCs, while I. lactea could be effectively applied to phytoremediation of contaminated soils by PHCs with at least 40,000 mg/kg.

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

Coagulation-flocculation process applied to wastewaters generated in hydrocarbon-contaminated soil washing

International Nuclear Information System (INIS)

Torres, L. g.; Belloc, C.; Iturbe, R.; Bandala, E.

2009-01-01

A wastewater produced in the contaminated soil washing was treated by means of coagulation-flocculation (CF) process. the wastewater treatment in this work continued petroleum hydrocarbons, a surfactant, i. e., sodium dodecyl sulphate (SDS) as well as salts, humic acids and other constituents that were lixiviated rom the soil during the washing process. The aim of this work was to develop a process for treating the wastewaters generated when washing hydrocarbon-contaminated soils in such a way that it could be recycled to the washing process, and at the end of the cleaning up, the waters could be disposed properly. (Author)

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

Improvements in the biotreatment of soil contaminated by heavy hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Paquin, J. [Sanexen Environmental Services Inc., Varennes, PQ (Canada)

2006-07-01

This presentation discussed improvements in the biotreatment of soil contaminated by heavy hydrocarbons. The presentation provided information on the background for the investigation such as: difficulty for biotreatment in soil to deal with heavy weathered hydrocarbons and fine grained soils; the involvement of the Montreal Centre of Excellence for Brownfield Remediation (MCEBR) to develop state of the art environmental solutions; and, the selection of Sanexen as the organization with the best price and best performance warranty to perform the required decontamination. The objectives of the study were to improve the performance of biotreatment of soil contaminated with heavy petroleum hydrocarbons; reduce soil biotreatment costs by 30 per cent; improve knowledge and understanding for this type of treatment; and, better identify constraints and optimal strategies in view of these constraints. Specific objectives that were discussed included: improving the microbial flora, attaining a favorable soil temperature at a low cost, identifying the best amendments for bulking of soil, increasing bio-availability of the contaminants, and identifying optimal mechanical handling of the soil. The presentation discussed soils treated; research and development carried out; standard method of biotreatment; alternative methods tested; initial investigation by the MCEBR; pilot test carried out by Sanexen; and, results of the pilot test. As part of the research program with MCEBR, soils that received different amendments were tested at the Biotechnology Research Institute (BRI) of the National Research Council for their ability to degrade added hexadecane and naphthalene. Soil at various stages of the treatment was also sampled and tested by the (BRI). It was concluded that the biotreatment of heavy hydrocarbons in fine grained soils is feasible and that the techniques used reduced biotreatment costs by approximately 25 per cent.

Bioremediation of hydrocarbon degradation in a petroleum-contaminated soil and microbial population and activity determination.

Science.gov (United States)

Wu, Manli; Li, Wei; Dick, Warren A; Ye, Xiqiong; Chen, Kaili; Kost, David; Chen, Liming

2017-02-01

Bioremediation of hydrocarbon degradation in petroleum-polluted soil is carried out by various microorganisms. However, little information is available for the relationships between hydrocarbon degradation rates in petroleum-contaminated soil and microbial population and activity in laboratory assay. In a microcosm study, degradation rate and efficiency of total petroleum hydrocarbons (TPH), alkanes, and polycyclic aromatic hydrocarbons (PAH) in a petroleum-contaminated soil were determined using an infrared photometer oil content analyzer and a gas chromatography mass spectrometry (GC-MS). Also, the populations of TPH, alkane, and PAH degraders were enumerated by a modified most probable number (MPN) procedure, and the hydrocarbon degrading activities of these degraders were determined by the Biolog (MT2) MicroPlates assay. Results showed linear correlations between the TPH and alkane degradation rates and the population and activity increases of TPH and alkane degraders, but no correlation was observed between the PAH degradation rates and the PAH population and activity increases. Petroleum hydrocarbon degrading microbial population measured by MPN was significantly correlated with metabolic activity in the Biolog assay. The results suggest that the MPN procedure and the Biolog assay are efficient methods for assessing the rates of TPH and alkane, but not PAH, bioremediation in oil-contaminated soil in laboratory. Copyright © 2016 Elsevier Ltd. All rights reserved.

High bacterial biodiversity increases degradation performance of hydrocarbons during bioremediation of contaminated harbor marine sediments

International Nuclear Information System (INIS)

Dell'Anno, Antonio; Beolchini, Francesca; Rocchetti, Laura; Luna, Gian Marco; Danovaro, Roberto

2012-01-01

We investigated changes of bacterial abundance and biodiversity during bioremediation experiments carried out on oxic and anoxic marine harbor sediments contaminated with hydrocarbons. Oxic sediments, supplied with inorganic nutrients, were incubated in aerobic conditions at 20 °C and 35 °C for 30 days, whereas anoxic sediments, amended with organic substrates, were incubated in anaerobic conditions at the same temperatures for 60 days. Results reported here indicate that temperature exerted the main effect on bacterial abundance, diversity and assemblage composition. At higher temperature bacterial diversity and evenness increased significantly in aerobic conditions, whilst decreased in anaerobic conditions. In both aerobic and anaerobic conditions, biodegradation efficiencies of hydrocarbons were significantly and positively related with bacterial richness and evenness. Overall results presented here suggest that bioremediation strategies, which can sustain high levels of bacterial diversity rather than the selection of specific taxa, may significantly increase the efficiency of hydrocarbon degradation in contaminated marine sediments. - Highlights: ► Bioremediation performance was investigated on hydrocarbon contaminated sediments. ► Major changes in bacterial diversity and assemblage composition were observed. ► Temperature exerted the major effect on bacterial assemblages. ► High bacterial diversity increased significantly biodegradation performance. ► This should be considered for sediment remediation by bio-treatments. - Bioremediation strategies which can sustain high levels of bacterial diversity may significantly increase the biodegradation of hydrocarbons in contaminated marine sediments.

Enhanced degradation activity by endophytic bacteria of plants growing in hydrocarbon contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Phillips, L.; Germida, J.J. [Saskatchewan Univ., Saskatoon, SK (Canada); Greer, C.W. [National Research Council of Canada, Montreal, PQ (Canada). Biotechnology Research Inst.

2006-07-01

The feasibility of using phytoremediation for cleaning soils contaminated with petroleum hydrocarbons was discussed. Petroleum hydrocarbons are problematic because of their toxicity, mobility and persistence in the environment. Appropriate clean-up methods are needed, given that 60 per cent of Canada's contaminated sites contain these compounds. Phytoremediation is an in situ biotechnology in which plants are used to facilitate contaminant removal. The approach relies on a synergistic relationship between plants and their root-associated microbial communities. Previous studies on phytoremediation have focussed on rhizosphere communities. However, it is believed that endophytic microbes may also play a vital role in organic contaminant degradation. This study investigated the structural and functional dynamics of both rhizosphere and endophytic microbial communities of plants from a phytoremediation field site in south-eastern Saskatchewan. The former flare pit contains up to 10,000 ppm of F3 to F4 hydrocarbon fractions. Root samples were collected from tall wheatgrass, wild rye, saltmeadow grass, perennial ryegrass, and alfalfa. Culture-based and culture-independent methods were used to evaluate the microbial communities associated with these roots. Most probable number assays showed that the rhizosphere communities contained more n-hexadecane, diesel fuel, and PAH degraders. However, mineralization assays with 14C labelled n-hexadecane, naphthalene, and phenanthrene showed that endophytic communities had more degradation activities per standardized initial degrader populations. Total community DNA samples taken from bulk, rhizosphere, and endophytic samples, were analyzed by denaturing gradient gel electrophoresis. It was shown that specific bacteria increased in endophytic communities compared to rhizosphere communities. It was suggested plants may possibly recruit specific bacteria in response to hydrocarbon contamination, thereby increasing degradation

Determination of the total amount of organically bound chlorine, bromine and iodine in environmental samples by instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Gether, J; Lunde, G [Central Institute for Industrial Research, Oslo (Norway); Steinnes, E [Institutt for Atomenergi, Kjeller (Norway)

1979-07-01

The determination of chlorine, bromine and iodine present as non-polar, hydrophobic hydrocarbons in environmental samples is reported. The organohalogen compounds are seprated from water into an organic phase by on-site liquid-liquid extraction, and form biological material by procedures based on lipid phase extraction and codistillation. After removal of inorganic halides by washing with water and concentration of the sample by evaporation of the solvent, the resulting extracts are analyzed for their chlorine, bromine and iodine contents by instrumental neutron activation analysus. Strict attention is paid to the possibility of contamination in every step of the procedure. Background values in routine analysis are approximately 100-200 ng of chlorine, <5 ng of bromine and <3 ng of iodine.

Interpretative approaches to identifying sources of hydrocarbons in complex contaminated environments

International Nuclear Information System (INIS)

Sauer, T.C.; Brown, J.S.; Boehm, P.D.

1993-01-01

Recent advances in analytical instrumental hardware and software have permitted the use of more sophisticated approaches in identifying or fingerprinting sources of hydrocarbons in complex matrix environments. In natural resource damage assessments and contaminated site investigations of both terrestrial and aquatic environments, chemical fingerprinting has become an important interpretative tool. The alkyl homologues of the major polycyclic and heterocyclic aromatic hydrocarbons (e.g., phenanthrenes/anthracenes, dibenzothiophenes, chrysenes) have been found to the most valuable hydrocarbons in differentiating hydrocarbon sources, but there are other hydrocarbon analytes, such as the chemical biomarkers steranes and triterpanes, and alkyl homologues of benzene, and chemical methodologies, such as scanning UV fluorescence, that have been found to be useful in certain environments. This presentation will focus on recent data interpretative approaches for hydrocarbon source identification assessments. Selection of appropriate targets analytes and data quality requirements will be discussed and example cases including the Arabian Gulf War oil spill results will be presented

Investigations on potential bacteria for the bioremediation treatment of environments contaminated with hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Lazar, I.; Voicu, A.; Dobrota, S.; Stefanescu, M. [Institute of Biology of Romanian Academy, Bucharest (Romania)] [and others

1995-12-31

In Romania after more than 135 years of oil production and processing, some severe environmental pollution problems have accumulated. In this context a joint research group from Institute of Biology Bucharest and S.C. Petrostar S.A. Ploiesti became involved in a research project on bioremediation of an environment contaminated with hydrocarbon waste. In the first stage of this project, investigations on microbial communities occurring in environments contaminated with oil were carried out. In the second stage, the hundreds of bacterial strains and populations isolated from soils, slops, and water sites contaminated with waste oil and water waste oil mix were submitted to a screening program, to select a naturally occurring mixed culture with a high ability to degrade hydrocarbons.

Prospects for arbuscular mycorrhizal fungi (AMF) to assist in phytoremediation of soil hydrocarbon contaminants.

Science.gov (United States)

Rajtor, Monika; Piotrowska-Seget, Zofia

2016-11-01

Arbuscular mycorrhizal fungi (AMF) form mutualistic associations with the roots of 80-90% of vascular plant species and may constitute up to 50% of the total soil microbial biomass. AMF have been considered to be a tool to enhance phytoremediation, as their mycelium create a widespread underground network that acts as a bridge between plant roots, soil and rhizosphere microorganisms. Abundant extramatrical hyphae extend the rhizosphere thus creating the hyphosphere, which significantly increases the area of a plant's access to nutrients and contaminants. The paper presents and evaluates the role and significance of AMF in phytoremediation of hydrocarbon contaminated sites. We focused on (1) an impact of hydrocarbons on arbuscular mycorrhizal symbiosis, (2) a potential of AMF to enhance phytoremediation, (3) determinants that influence effectiveness of hydrocarbon removal from contaminated soils. This knowledge may be useful for selection of proper plant and fungal symbionts and crucial to optimize environmental conditions for effective AMF-mediated phytoremediation. It has been concluded that three-component phytoremediation systems based on synergistic interactions between plant roots, AMF and hydrocarbon-degrading microorganisms demonstrated high effectiveness in dissipation of organic pollutants in soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prediction of Petroleum Hydrocarbon Bioavailability in Contaminated Soils and Sediments

NARCIS (Netherlands)

Cuypers, M.P.; Clemens, R.; Grotenhuis, J.T.C.; Rulkens, W.H.

2001-01-01

Recently, several laboratory methods have been developed for the prediction of contaminant bioavailability. So far, none of these methods has been extensively tested for petroleum hydrocarbons. In the present study we investigated solid-phase extraction and persulfate oxidation for the prediction of

Are Microbial Nanowires Responsible for Geoelectrical Changes at Hydrocarbon Contaminated Sites?

Science.gov (United States)

Hager, C.; Atekwana, E. A.; Gorby, Y. A.; Duris, J. W.; Allen, J. P.; Atekwana, E. A.; Ownby, C.; Rossbach, S.

2007-05-01

Significant advances in near-surface geophysics and biogeophysics in particular, have clearly established a link between geoelectrical response and the growth and enzymatic activities of microbes in geologic media. Recent studies from hydrocarbon contaminated sites suggest that the activities of distinct microbial populations, specifically syntrophic, sulfate reducing, and dissimilatory iron reducing microbial populations are a contributing factor to elevated sediment conductivity. However, a fundamental mechanistic understanding of the processes and sources resulting in the measured electrical response remains uncertain. The recent discovery of bacterial nanowires and their electron transport capabilities suggest that if bacterial nanowires permeate the subsurface, they may in part be responsible for the anomalous conductivity response. In this study we investigated the microbial population structure, the presence of nanowires, and microbial-induced alterations of a hydrocarbon contaminated environment and relate them to the sediments' geoelectrical response. Our results show that microbial communities varied substantially along the vertical gradient and at depths where hydrocarbons saturated the sediments, ribosomal intergenic spacer analysis (RISA) revealed signatures of microbial communities adapted to hydrocarbon impact. In contrast, RISA profiles from a background location showed little community variations with depth. While all sites showed evidence of microbial activity, a scanning electron microscope (SEM) study of sediment from the contaminated location showed pervasive development of "nanowire-like structures" with morphologies consistent with nanowires from laboratory experiments. SEM analysis suggests extensive alteration of the sediments by microbial Activity. We conclude that, excess organic carbon (electron donor) but limited electron acceptors in these environments cause microorganisms to produce nanowires to shuttle the electrons as they seek for

Characterization of bacterial community structure in a hydrocarbon-contaminated tropical African soil.

Science.gov (United States)

Salam, Lateef B; Ilori, Mathew O; Amund, Olukayode O; LiiMien, Yee; Nojiri, Hideaki

2018-04-01

The bacterial community structure in a hydrocarbon-contaminated Mechanical Engineering Workshop (MWO) soil was deciphered using 16S rRNA gene clone library analysis. Four hundred and thirty-seven clones cutting across 13 bacterial phyla were recovered from the soil. The representative bacterial phyla identified from MWO soil are Proteobacteria, Bacteroidetes, Chloroflexi, Acidobacteria, Firmicutes, Actinobacteria, Verrucomicrobia, Planctomycetes, Ignavibacteriae, Spirochaetes, Chlamydiae, Candidatus Saccharibacteria and Parcubacteria. Proteobacteria is preponderant in the contaminated soil (51.2%) with all classes except Epsilonproteobacteria duly represented. Rarefaction analysis indicates 42%, 52% and 77% of the clone library is covered at the species, genus and family/class delineations with Shannon diversity (H') and Chao1 richness indices of 5.59 and 1126, respectively. A sizeable number of bacterial phylotypes in the clone library shared high similarities with strains previously described to be involved in hydrocarbon biodegradation. Novel uncultured genera were identified that have not been previously reported from tropical African soil to be associated with natural attenuation of hydrocarbon pollutants. This study establishes the involvement of a wide array of physiologically diverse bacterial groups in natural attenuation of hydrocarbon pollutants in soil.

Biological Activity Assessment in Mexican Tropical Soils with Different Hydrocarbon Contamination Histories

OpenAIRE

Riveroll-Larios, Jessica; Escalante-Espinosa, Erika; Fócil-Monterrubio, Reyna L.; Díaz-Ramírez, Ildefonso J.

2015-01-01

The use of soil health indicators linked to microbial activities, such as key enzymes and respirometric profiles, helps assess the natural attenuation potential of soils contaminated with hydrocarbons. In this study, the intrinsic physicochemical characteristics, biological activity and biodegradation potential were recorded for two soils with different contamination histories (>5 years and

Hydrocarbon contamination of coastal sediments from the Sfax area (Tunisia), Mediterranean Sea.

Science.gov (United States)

Louati, A; Elleuch, B; Kallel, M; Saliot, A; Dagaut, J; Oudot, J

2001-06-01

The coastal area off the city of Sfax (730,000 inhabitants), well-known for fisheries and industrial activities, receives high inputs of organic matter mostly anthropogenic. Eighteen stations were selected in the vicinity of the direct discharge of industrial sewage effluents in the sea in order to study the spatial distribution of the organic contamination. Surface sediments sampled in the shallow shelf were analysed for hydrocarbons by Fourier transform infrared spectroscopy, gas chromatography and gas chromatography/mass spectrometry. Total hydrocarbon distributions revealed high contamination as compared to other coastal Mediterranean sites, with an average concentration of 1865 ppm/dry weight sediment. Gas chromatographic distribution patterns, values of unresolved mixture/n-alkane ratio and distributions of steranes and hopanes confirmed a petroleum contamination of the Arabian light crude oil type. Biogenic compounds were also identified with a series of short-chain carbon-numbered n-alkenes in the carbon range 16-24.

Biological indicators capable of assessing thermal treatment efficiency of hydrocarbon mixture-contaminated soil.

Science.gov (United States)

Wang, Jiangang; Zhan, Xinhua; Zhou, Lixiang; Lin, Yusuo

2010-08-01

In China, there are many special sites for recycling and washing the used drums, which release a variety of C5-C40 hydrocarbon mixture into the soil around the site. The remediation of these contaminated sites by thermal treatment is adopted ubiquitously and needs to be assessed. Here we report the feasibility of biological indicators applied to assess thermal treatment efficiency in such contaminated soil. A series of biological indicators, including seed germination index (SGI), root elongation index (REI), plant growth height, biomass, carbon dioxide evolved (CDE), soil respiration inhibition (SRI) and soil enzymatic activities, were employed to monitor or assess hydrocarbon mixture removal in thermal treated soil. The results showed that residual hydrocarbon mixture content correlated strongly negatively with SGI for sesamum (Sesamum indicum L.), plant height, and biomass for ryegrass (Lolium perenne L.) in the concentration ranges of 0-3990, 0-3170 and 0-2910 mg kg(-1), respectively. In contrast, REI for sesamum was positively correlated with residual hydrocarbon mixture content from 0 to 1860 mg kg(-1). In addition, both CDE and SRI demonstrated that 600 mg kg(-1) of residual hydrocarbon mixture content caused the highest amount of soil carbon dioxide emission and inhabitation of soil respiration. The results of soil enzymes indicated that 1000 mg kg(-1) of residual hydrocarbon mixture content was the threshold value of stimulating or inhibiting the activities of phosphatase and catalase, or completely destroying the activities of dehydrogenase, invertase, and urease. In conclusion, these biological indicators can be used as a meaningful complementation for traditional chemical content measurement in evaluating the environmental risk of the contaminated sites before and after thermal treatment. (c) 2010 Elsevier Ltd. All rights reserved.

Comparative analyses of contaminant levels in bottom feeding and predatory fish using the National Contaminant Biomonitoring Program data

Energy Technology Data Exchange (ETDEWEB)

Kidwell, J.M. [Clement International Corp., Fairfax, VA (United States); Phillips, L.J. [Versar Inc., Springfield, VA (United States); Birchard, G.F. [George Mason Univ., Fairfax, VA (United States)

1995-06-01

Both bottom feeding and predatory fish accumulate chemical contaminants found in water. Bottom feeders are readily exposed to the greater quantities of chlorinated hydrocarbons and metals that accumulate in sediments. Predators, on the other hand, may bioaccumulate organochlorine pesticides, PCBs, and metals from the surrounding water or from feeding on other fish, including bottom feeders, which may result in the biomagnification of these compounds in their tissues. This study used National Contaminant Biomonitoring Program data produced by the Fish and Wildlife Service to test the hypothesis that differences exist between bottom feeders and predators in tissue levels of organochlorine pesticides, PCBs, and metals. 7 refs., 2 tabs.

Screening of extremotolerant fungi for the bioremediation of hydrocarbon contaminated sites

Science.gov (United States)

Poyntner, Caroline; Blasi, Barbara; Prenafeta, Francesc; Sterflinger, Katja

2015-04-01

Bioremediation can be used to treat contaminated sites, by taking advantage of microorganisms which have the potential to degrade a wide range of contaminants. While research has been focused mainly on bacteria, the knowledge on other microorganisms, especially fungal communities, is still limited. However, the use of fungi may have advantages compared to bacteria. Extremophile fungi like the black yeasts can withstand high levels of environmental stress (e.g. range of pH, water availability and temperature, presence of toxic chemicals). Therefore they might be applicable in situations, where bacterial communities show limited performance. In order to identify fungi which are good candidates for bioremediation application, a selection of 163 fungal strains, mostly from the group of the black yeasts, was tested for their capability to degrade three different pollutants: hexadecane, toluene, and polychlorinated biphenyl 126, which were used as model compounds for aliphatic hydrocarbons, aromatic hydrocarbons and polychlorinated biphenyls. These chemicals are frequently found in sites contaminated by oil, gas and coal. The screening was based on a two-step selection approach. As a first step, a high throughput method was developed to screen the relatively large amount of fungal strains regarding their tolerance to the contaminants. A microtiter plate based method was developed for monitoring fungal growth in the presence of the selected contaminants photometrically with a Tecan reader. Twenty five strains out of 163, being species of the genera Cladophilaophora, Scedosporium and Exophiala, showed the ability to grow on at least 2 hydrocarbons, and are therefore the most promising candidates for further tests. In a second step, degradation of the contaminants was investigated in more detail for a subset of the screened fungi. This was done by closing the carbon balance in sealed liquid cultures in which the selected pollutant was introduce as the sole source of carbon

[Formation mechanism and chemical safety of nonintentional chemical substances present in chlorinated drinking water and wastewater].

Science.gov (United States)

Onodera, Sukeo

2010-09-01

This paper reviews the formation mechanism and chemical safety of nonintentional chemical substances (NICS) present in chlorine-treated water containing organic contaminants. Undesirable compounds, i.e., NICS, may be formed under certain conditions when chlorine reacts with organic matter. The rate and extent of chlorine consumption with organics are strongly dependent on their chemical structures, particularly whether double bonds or sulfur and nitrogen atoms occur in the molecules. Organothiophosphorus pesticides (P=S type) are easily oxidized to their phosphorus compounds (P=O type) in chlorinated water containing HOCl as little as 0.5 mg/l, resulting in an increase in cholinesterase-inhibitory activity. Chlorination of phenols in water also produces a series of highly chlorinated compounds, including chlorophenols, chloroquinones, chlorinated carboxylic acids, and polychlorinated phenoxyphenols (PCPPs). In some of these chloroquinones, 2,6-dichloroalkylsemiquinones exhibit a strong mutagenic response as do positive controls used in the Ames test. 2-phenoxyphenols in these PCPPs are particularly interesting, as they are present in the chlorine-treated phenol solution and they are also precursors (predioxins) of the highly toxic chlorinated dioxins. Polynuclear aromatic hydrocarbons (PAHs) were found to undergo chemical changes due to hypochlorite reactions to give chloro-substituted PAHs, oxygenated (quinones) and hydroxylated (phenols) compounds, but they exhibit a lower mutagenic response. In addition, field work was performed in river water and drinking water to obtain information on chemical distribution and their safety, and the results are compared with those obtained in the model chlorination experiments.

POLYCYCLIC AROMATIC HYDROCARBON CONTAMINATION LEVELS IN COLLECTED SAMPLES FROM VICINITY OF A HIGHWAY

Directory of Open Access Journals (Sweden)

S. V. Samimi ، R. Akbari Rad ، F. Ghanizadeh

2009-01-01

Full Text Available Tehran as the biggest city of Iran with a population of more than 10 millions has potentially high pollutant exposures of gas oil and gasoline combustion from vehicles that are commuting in the highways every day. The vehicle exhausts contain polycyclic aromatic hydrocarbons, which are produced by incomplete combustion and can be directly deposited in the environment. In the present study, the presence of polycyclic aromatic hydrocarbons contamination in the collected samples of a western highway in Tehran was investigated. The studied location was a busy highway in Tehran. High performance liquid chromatography equipped with florescence detector was used for determination of polycyclic aromatic hydrocarbons concentrations in the studied samples. Total concentration of the ten studied polycyclic aromatic hydrocarbons compounds ranged from 11107 to 24342 ng/g dry weight in the dust samples and increased from 164 to 2886 ng/g dry weight in the soil samples taken from 300 m and middle of the highway, respectively. Also the average of Σ PAHs was 1759 ng/L in the water samples of pools in parks near the highway. The obtained results indicated that polycyclic aromatic hydrocarbons contamination levels were very high in the vicinity of the highway.

A study of chlorinated solvent contamination of the aquifers of an industrial area in central Italy: a possibility of bioremediation

Directory of Open Access Journals (Sweden)

FEDERICA eMATTEUCCI

2015-09-01

Full Text Available Perchloroethene, Trichloroethene, and other chlorinated solvents are widespread groundwater pollutants. They form Dense Non Aqueous Phase Liquids (DNAPLs that sink through permeable groundwater aquifers until non-permeable zone is reached. In Italy there are many situations of serious contamination of groundwater that might compromise their use in industry, agriculture, private, as the critical case of a Central Italy valley located in the province of Teramo (Val Vibrata, characterized by a significant chlorinated solvents contamination. Data from the various monitoring campaigns that have taken place over time were collected, and new samplings were carried out, resulting in a complete database. The data matrix was processed with a multivariate statistic analysis (in particular Principal Components Analysis, PCA and was then imported into Geographic Information System (GIS, to obtain a model of the contamination. A microcosm anaerobic study was utilized to assess the potential for in situ natural or enhanced bioremediation. Most of the microcosms were positive for dechlorination, particularly those inoculated with a mineral medium. This indicate the presence of an active native dechlorinating population in the subsurface, probably inhibited by co-contaminants in the groundwater, or more likely by the absence or lack of nutritional factors. Among the tested electron donors (i.e., yeast extract, lactate, and butyrate lactate and butyrate enhanced dechlorination of chlorinated compounds. PCA and GIS studies allowed delimiting the contamination; the microcosm study helped to identify the conditions to promote the bioremediation of the area.

Development of an efficient bacterial consortium for the potential remediation of hydrocarbons from contaminated sites

Directory of Open Access Journals (Sweden)

Kaustuvmani Patowary

2016-07-01

Full Text Available The intrinsic biodegradability of hydrocarbons and the distribution of proficient degrading microorganisms in the environment are very crucial for the implementation of bioremediation practices. Among others, one of the most favorable methods that can enhance the effectiveness of bioremediation of hydrocarbon-contaminated environment is the application of biosurfactant producing microbes. In the present study, the biodegradation capacities of native bacterial consortia towards total petroleum hydrocarbons (TPH with special emphasis to poly aromatic hydrocarbons (PAHs were determined. The purpose of the study was to isolate TPH degrading bacterial strains from various petroleum contaminated soil of Assam, India and develop a robust bacterial consortium for bioremediation of crude oil of this native land. From a total of 23 bacterial isolates obtained from three different hydrocarbons contaminated samples 5 isolates, namely KS2, PG1, PG5, R1 and R2 were selected as efficient crude oil degraders with respect to their growth on crude oil enriched samples. Isolates KS2, PG1 and R2 are biosurfactant producers and PG5, R1 are non-producers. Fourteen different consortia were designed involving both biosurfactant producing and non-producing isolates. Consortium 10, which comprises two Bacillus strains namely, Bacillus pumilus KS2 and Bacillus cereus R2 (identified by 16s rRNA sequencing has shown the best result in the desired degradation of crude oil. The consortium showed degradation up to 84.15% of total petroleum hydrocarbon (TPH after five weeks of incubation, as revealed from gravimetric analysis. FTIR (Fourier transform infrared and GCMS (Gas chromatography-mass spectrometer analyses were correlated with gravimetric data which reveals that the consortium has removed a wide range of petroleum hydrocarbons in comparison with abiotic control including different aliphatic and aromatic hydrocarbons.

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.

Assessment of phytoremediation as an in-situ technique for cleaning oil-contaminated sites

Energy Technology Data Exchange (ETDEWEB)

Frick, C M; Germida, J J; Farrell, R E [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Soil Science

1999-01-01

The effectiveness of phytoremediation as a tool for cleaning up hydrocarbon contaminated soil and groundwater was evaluated by reviewing relative literature. Phytoremediation is an emerging technology which consists of the use of plants for in situ treatment of contaminated soils. Grasses, herbs, shrubs and deciduous trees were the main types of plants considered in this study. A database is presently under construction to act as an inventory of plant species that tolerate or phytoremediate petroleum hydrocarbons. This paper focused on the main mechanisms and special considerations involved in the phytoremediation alkanes, aromatics, polycyclic aromatic hydrocarbons, and creosote. While phytoremediation does not require intensive engineering techniques, it does involve human intervention to establish appropriate plants and microorganisms to enhance natural degradation processes. Plants such as canola, oats barley have been shown to tolerate and accumulate metals such as selenium, copper, cadmium and zinc. Hybrid poplar trees reduce the concentration of nitrate in surficial groundwater and degrade the herbicide atrazine. Forage grasses inoculated with bacteria can degrade chlorinated benzoic acids. Various grasses and leguminous plants can increase the removal of petroleum hydrocarbons from contaminated soils. 66 refs., 3 tabs., 2 figs.

Assessment of phytoremediation as an in-situ technique for cleaning oil-contaminated sites

International Nuclear Information System (INIS)

Frick, C.M.; Germida, J.J.; Farrell, R.E.

1999-01-01

The effectiveness of phytoremediation as a tool for cleaning up hydrocarbon contaminated soil and groundwater was evaluated by reviewing relative literature. Phytoremediation is an emerging technology which consists of the use of plants for in situ treatment of contaminated soils. Grasses, herbs, shrubs and deciduous trees were the main types of plants considered in this study. A database is presently under construction to act as an inventory of plant species that tolerate or phytoremediate petroleum hydrocarbons. This paper focused on the main mechanisms and special considerations involved in the phytoremediation alkanes, aromatics, polycyclic aromatic hydrocarbons, and creosote. While phytoremediation does not require intensive engineering techniques, it does involve human intervention to establish appropriate plants and microorganisms to enhance natural degradation processes. Plants such as canola, oats barley have been shown to tolerate and accumulate metals such as selenium, copper, cadmium and zinc. Hybrid poplar trees reduce the concentration of nitrate in surficial groundwater and degrade the herbicide atrazine. Forage grasses inoculated with bacteria can degrade chlorinated benzoic acids. Various grasses and leguminous plants can increase the removal of petroleum hydrocarbons from contaminated soils. 66 refs., 3 tabs., 2 figs

ZVI-Clay remediation of a chlorinated solvent source zone, Skuldelev, Denmark: 2. Groundwater contaminant mass discharge reduction

DEFF Research Database (Denmark)

Fjordbøge, Annika Sidelmann; Lange, Ida Vedel; Bjerg, Poul Løgstrup

2012-01-01

The impact of source mass depletion on the down-gradient contaminant mass discharge was monitored for a 19-month period as a part of a field demonstration of the ZVI-Clay soil mixing remediation technology. Groundwater samples were collected from conventional monitoring wells (120 samples) and a ...... down-gradient contaminant mass discharge reduction (76%) for the parent compound (PCE), while the overall reduction of chlorinated ethenes was smaller (21%)....

Evaluation of solid polymeric organic materials for use in bioreactive sediment capping to stimulate the degradation of chlorinated aliphatic hydrocarbons

NARCIS (Netherlands)

Atashgahi, S.; Maphosa, F.; Vrieze, de J.; Haest, P.J.; Boon, N.; Smidt, H.; Springael, D.; Dejonghe, W.

2014-01-01

In situ bioreactive capping is a promising technology for mitigation of surface water contamination by discharging polluted groundwater. Organohalide respiration (OHR) of chlorinated ethenes in bioreactive caps can be stimulated through incorporation of solid polymeric organic materials (SPOMs) that

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

Bioremediation a potential approach for soil contaminated with polycyclic aromatic hydrocarbons: An Overview

OpenAIRE

Norzila Othman; Mohd Irwan Juki; Norhana Hussain; Suhaimi Abdul Talib

2011-01-01

Polycyclic aromatic hydrocarbons (PAHs) represent a group of priority pollutants which are present at high concentration in soils of many industrially contaminated sites. Standards and criteria for the remediation of soils contaminated with PAHs vary widely between countries. Bioremediation has gained preference as a technology for remediation contaminated sites as it is less expensive and more environmental friendly. Bioremediation utilizes microorganisms to degrade PAHs to less toxic compou...

Avoidance of polycyclic aromatic hydrocarbon-contaminated sediments by the freshwater invertebrates Gammarus pulex and Asellus aquaticus

NARCIS (Netherlands)

Lange, de H.J.; Sperber, V.; Peeters, E.T.H.M.

2006-01-01

Contamination of sediments is a serious problem in most industrialized areas. Sediments are often contaminated with trace metals and organic contaminants like polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Bioassays are often used to determine the effect of

Combination of biochar amendment and phytoremediation for hydrocarbon removal in petroleum-contaminated soil.

Science.gov (United States)

Han, Tao; Zhao, Zhipeng; Bartlam, Mark; Wang, Yingying

2016-11-01

Remediation of soils contaminated with petroleum is a challenging task. Four different bioremediation strategies, including natural attenuation, biochar amendment, phytoremediation with ryegrass, and a combination of biochar and ryegrass, were investigated with greenhouse pot experiments over a 90-day period. The results showed that planting ryegrass in soil can significantly improve the removal rate of total petroleum hydrocarbons (TPHs) and the number of microorganisms. Within TPHs, the removal rate of total n-alkanes (45.83 %) was higher than that of polycyclic aromatic hydrocarbons (30.34 %). The amendment of biochar did not result in significant improvement of TPH removal. In contrast, it showed a clear negative impact on the growth of ryegrass and the removal of TPHs by ryegrass. The removal rate of TPHs was significantly lower after the amendment of biochar. The results indicated that planting ryegrass is an effective remediation strategy, while the amendment of biochar may not be suitable for the phytoremediation of soil contaminated with petroleum hydrocarbons.

Biodegradation Of Polycyclic Aromatic Hydrocarbons In Petroleum Oil Contaminating The Environment

International Nuclear Information System (INIS)

Partila, A.M.

2013-01-01

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in urban atmospheres (Chen et al., 2013). PAHs enter the environment via incomplete combustion of fossil fuels and accidental leakage of petroleum products, and as components of products such as creosote (Muckian et al., 2009). Due to PAHs carcinogenic activity, they have been included in the European Union (EU) and the Environmental Protection Agency (EPA) priority pollutant lists. Human exposure to PAHs occurs in three ways, inhalation, dermal contact and consumption of contaminated foods, which account for 88-98% of such contamination; in other words, diet is the major source of human exposure to these contaminants (Rey-Salgueiro et al., 2008). Both the World Health Organization and the UK Expert Panel on Air Quality Standards (EPAQS) have considered benzo(a)pyrene (BaP) as a marker of the carcinogenic potency of the polycyclic aromatic hydrocarbons (PAH) mixture (Delgado-Saborit et al., 2011). Polycyclic aromatic and heavier aliphatic hydrocarbons, which have a stable recalcitrant molecular structure, exhibit high hydrophobicity and low aqueous solubility, are not readily removed from soil through leaching and volatilization (Brassington et al., 2007). The hydrophobicity of PAHs limits desorption to the aqueous phase (Donlon et al., 2002). Six main ways of dissipation, i.e. disappearance, are recognized in the environment: volatilization, photooxidation, Aim of the Work chemical oxidation, sorption, leaching and biodegradation. Microbial degradation is considered to be the main process involved in the dissipation of PAH (Yuan et al., 2002). Thus, more and more research interests are turning to the biodegradation of PAHs. Some microorganisms can utilize PAHs as a source of carbon and energy so that PAHs can be degraded to carbon dioxide and water, or transformed to other nontoxic or low-toxic substances (Perelo, 2010). Compared with other physical and chemical methods such as combustion

Hydrodynamic analysis application of contaminated groundwater remediation to oil hydrocarbons

Directory of Open Access Journals (Sweden)

Pajić Predrag R.

2017-01-01

Full Text Available In this paper, the application of the hydrodynamic analysis in the selected ‘pumping and treatment’ remediation method of groundwater hydrocarbon pollution in the case of the Pancevo oil refinery is examined. The applied hydrodynamic analysis represents a regular and necessary approach in modern hydrogeology. Previous chemical analysis of soil and groundwater samples at observation objects revealed their pollution by oil products. New researches included the constraction of 12 piezometric boreholes of varying depths, geoelectric soil sounding, ‘in situ’ measurement of the present contaminant, detected as a hydrophobic phase of LNAPL, chemical analysis of soil and groundwater samples with emphasis on total petroleum hydrocarbons (TPH content, total fats and mineral oils, mercury cations and other characteristic compounds, etc. These researches define the volume of contamination issued by the ‘light’ (LNAPL contamination phase. The selected remediation method for this type of pollution is the ‘Pump and Treat’ method, which implies the pumping of contaminated groundwater from aquifer and their subsequent treatment. A hydrodynamic method was used to select the optimal hydrotechnical solution for LNAPL extraction. On the mathematical model, the prediction calculations for two variant solutions were carried out (‘hydraulic isolation’ and complex for the application of groundwater contamination remediation characterized as front pollution substance (by extraction and injection wells or infiltration pool. By extraction wells performing, it would be possible to remove the LNAPL from the surface of the water with special pumps-skimmers. The importance of the hydrodynamic method application is, in addition to the hydrotechnical solution selection for the LNAPL drainage, the provision of quality basis for the dimensioning of these objects based on the results of the groundwater balance.

Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site

International Nuclear Information System (INIS)

Akbari, Ali; Ghoshal, Subhasis

2014-01-01

Highlights: • Aeration and moisture addition alone caused extensive hydrocarbon biodegradation. • 30-day slurry reactor remediation endpoints attained in 385 days in biopiles. • High nitrogen concentrations inhibited hydrocarbon degradation. • Inhibition of biodegradation linked to lack of shifts in soil microbial community. - Abstract: Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16–C34) in a pilot-scale biopile experiment conducted at 15 °C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16–C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day −1 in biopile tank compared to 0.11 day −1 in slurry bioreactors for C16–C34 hydrocarbons, the biodegradation extents for this fraction were

Development of an Efficient Bacterial Consortium for the Potential Remediation of Hydrocarbons from Contaminated Sites.

Science.gov (United States)

Patowary, Kaustuvmani; Patowary, Rupshikha; Kalita, Mohan C; Deka, Suresh

2016-01-01

The intrinsic biodegradability of hydrocarbons and the distribution of proficient degrading microorganisms in the environment are very crucial for the implementation of bioremediation practices. Among others, one of the most favorable methods that can enhance the effectiveness of bioremediation of hydrocarbon-contaminated environment is the application of biosurfactant producing microbes. In the present study, the biodegradation capacities of native bacterial consortia toward total petroleum hydrocarbons (TPH) with special emphasis to poly aromatic hydrocarbons were determined. The purpose of the study was to isolate TPH degrading bacterial strains from various petroleum contaminated soil of Assam, India and develop a robust bacterial consortium for bioremediation of crude oil of this native land. From a total of 23 bacterial isolates obtained from three different hydrocarbons contaminated samples five isolates, namely KS2, PG1, PG5, R1, and R2 were selected as efficient crude oil degraders with respect to their growth on crude oil enriched samples. Isolates KS2, PG1, and R2 are biosurfactant producers and PG5, R1 are non-producers. Fourteen different consortia were designed involving both biosurfactant producing and non-producing isolates. Consortium 10, which comprises two Bacillus strains namely, Bacillus pumilus KS2 and B. cereus R2 (identified by 16s rRNA sequencing) has shown the best result in the desired degradation of crude oil. The consortium showed degradation up to 84.15% of TPH after 5 weeks of incubation, as revealed from gravimetric analysis. FTIR (Fourier transform infrared) and GCMS (Gas chromatography-mass spectrometer) analyses were correlated with gravimetric data which reveals that the consortium has removed a wide range of petroleum hydrocarbons in comparison with abiotic control including different aliphatic and aromatic hydrocarbons.

Use of biological activities to monitor the removal of fuel contaminants - perspective for monitoring hydrocarbon contamination: A review

CSIR Research Space (South Africa)

Maila, MP

2005-01-01

Full Text Available Soil biological activities are vital for the restoration of soil contaminated with hydrocarbons. Their role includes the biotransformation of petroleum compounds into harmless compounds. In this paper, the use of biological activities as potential...

Bioavailability and bioaccessibility of petroleum hydrocarbons in contaminated site soils

International Nuclear Information System (INIS)

Stephenson, G.; Angell, R.; Strive, E.; Ma, W.

2010-01-01

Although the bioavailability and/or bioaccessibility of contaminants in soil can be measured by various ecological receptors, the methods that are suitable for metals do not necessarily work well for petroleum hydrocarbons (PHCs). In this study, several biological and chemical methods were used at various PHC contaminated sites to find the most fitting method for different soil types in terms of predicting the biological responses of organisms as measured by standard single species toxicity tests. Organisms such as plants, earthworms, and collembolan were exposed to soils with different PHC concentrations. Multiple endpoints were then measured to evaluate the biological responses. The exposure concentrations for the 4 CCME hydrocarbon fractions were measured using hexane:acetone extraction as well as extractions with cyclodextrin, and a mixture of enzymes to simulate the gastro-intestinal fluid of an earthworm. The estimated exposure concentrations depended on the extraction method. The study showed that existing methodologies must be modified in order to better estimate the biological effect of PHCs in soil. Comparative data was presented and discussed along with proposed methodological modifications.

Bioavailability and bioaccessibility of petroleum hydrocarbons in contaminated site soils

Energy Technology Data Exchange (ETDEWEB)

Stephenson, G.; Angell, R.; Strive, E.; Ma, W. [Stantec Consulting Ltd., Surrey, BC (Canada)

2010-07-01

Although the bioavailability and/or bioaccessibility of contaminants in soil can be measured by various ecological receptors, the methods that are suitable for metals do not necessarily work well for petroleum hydrocarbons (PHCs). In this study, several biological and chemical methods were used at various PHC contaminated sites to find the most fitting method for different soil types in terms of predicting the biological responses of organisms as measured by standard single species toxicity tests. Organisms such as plants, earthworms, and collembolan were exposed to soils with different PHC concentrations. Multiple endpoints were then measured to evaluate the biological responses. The exposure concentrations for the 4 CCME hydrocarbon fractions were measured using hexane:acetone extraction as well as extractions with cyclodextrin, and a mixture of enzymes to simulate the gastro-intestinal fluid of an earthworm. The estimated exposure concentrations depended on the extraction method. The study showed that existing methodologies must be modified in order to better estimate the biological effect of PHCs in soil. Comparative data was presented and discussed along with proposed methodological modifications.

Microbial and molecular techniques to evaluate and to implement in-situ biodegradation potential and activity at sites contaminated with aromatic and chlorinated hydrocarbons

International Nuclear Information System (INIS)

Karg, F.; Henkler, Ch.

2005-01-01

Intrinsic bio-remediation harnesses the ability of indigenous microorganisms to degrade contaminants that are present in soil and groundwater. Over the past decade many environmental regulatory agencies especially in Europe have come to recognize the importance of these natural processes in contaminant attenuation. In order to use in-situ bio-remediation to clean up a site successfully it is necessary to investigate the indigenous microbial population and its potential activity to degrade the contaminants of concern (COCs). The evaluation of naturally-occurring degradative activity in initial screening of soil and groundwater samples using recently developed molecular and microbial methods may allow for the implementation of a contaminant reduction and management program without the need for fully engineered remediation intervention. Limited engineering approaches (nutrient delivery etc.) can be implemented to support naturally-occurring bio-restoration processes to achieve a controlled, dynamic attenuation of COCs. Techniques for monitoring pollutant-degrading microorganisms were previously limited to standard culturing techniques. More recently, techniques based upon detection of genetic elements and metabolic activities have been developed in collaboration with university partners Europe, especially in France. The modern techniques are more sensitive for monitoring microbial populations, metabolic activity and the genetic potential to degrade the COCs, and avoid the need for cultivation of microbes under artificial conditions in the laboratory. Especially the application of PCR-Tests (Polymerase Chain Reaction) are able to quantify the Genetic Potential of Pollutant Microbiological Degradation on a contaminated site. This enables to use very economic in-situ site rehabilitation strategies as for example (Dynamic Natural Attenuation). For this modern application of these new strategies PLANREAL created with HPC Envirotec and together with a French University

Bioremediation and reclamation of soil contaminated with petroleum oil hydrocarbons by exogenously seeded bacterial consortium: a pilot-scale study.

Science.gov (United States)

Mukherjee, Ashis K; Bordoloi, Naba K

2011-03-01

Spillage of petroleum hydrocarbons causes significant environmental pollution. Bioremediation is an effective process to remediate petroleum oil contaminant from the ecosystem. The aim of the present study was to reclaim a petroleum oil-contaminated soil which was unsuitable for the cultivation of crop plants by using petroleum oil hydrocarbon-degrading microbial consortium. Bacterial consortium consisting of Bacillus subtilis DM-04 and Pseudomonas aeruginosa M and NM strains were seeded to 20% (v/w) petroleum oil-contaminated soil, and bioremediation experiment was carried out for 180 days under laboratory condition. The kinetics of hydrocarbon degradation was analyzed using biochemical and gas chromatographic (GC) techniques. The ecotoxicity of the elutriates obtained from petroleum oil-contaminated soil before and post-treatment with microbial consortium was tested on germination and growth of Bengal gram (Cicer aretinum) and green gram (Phaseolus mungo) seeds. Bacterial consortium showed a significant reduction in total petroleum hydrocarbon level in contaminated soil (76% degradation) as compared to the control soil (3.6% degradation) 180 days post-inoculation. The GC analysis confirmed that bacterial consortium was more effective in degrading the alkane fraction compared to aromatic fraction of crude petroleum oil hydrocarbons in soil. The nitrogen, sulfur, and oxygen compounds fraction was least degraded. The reclaimed soil supported the germination and growth of crop plants (C. aretinum and P. mungo). In contrast, seeds could not be germinated in petroleum oil-contaminated soil. The present study reinforces the application of bacterial consortium rather than individual bacterium for the effective bioremediation and reclamation of soil contaminated with petroleum oil.

Contrasting the community structure of arbuscular mycorrhizal fungi from hydrocarbon-contaminated and uncontaminated soils following willow (Salix spp. L. planting.

Directory of Open Access Journals (Sweden)

Saad El-Din Hassan

Full Text Available Phytoremediation is a potentially inexpensive alternative to chemical treatment of hydrocarbon-contaminated soils, but its success depends heavily on identifying factors that govern the success of root-associated microorganisms involved in hydrocarbon degradation and plant growth stimulation. Arbuscular mycorrhizal fungi (AMF form symbioses with many terrestrial plants, and are known to stimulate plant growth, although both species identity and the environment influence this relationship. Although AMF are suspected to play a role in plant adaptation to hydrocarbon contamination, their distribution in hydrocarbon-contaminated soils is not well known. In this study, we examined how AMF communities were structured within the rhizosphere of 11 introduced willow cultivars as well as unplanted controls across uncontaminated and hydrocarbon-contaminated soils at the site of a former petrochemical plant. We obtained 69 282 AMF-specific 18S rDNA sequences using 454-pyrosequencing, representing 27 OTUs. Contaminant concentration was the major influence on AMF community structure, with different AMF families dominating at each contaminant level. The most abundant operational taxonomic unit in each sample represented a large proportion of the total community, and this proportion was positively associated with increasing contamination, and seemingly, by planting as well. The most contaminated soils were dominated by three phylotypes closely related to Rhizophagus irregularis, while these OTUs represented only a small proportion of sequences in uncontaminated and moderately contaminated soils. These results suggest that in situ inoculation of AMF strains could be an important component of phytoremediation treatments, but that strains should be selected from the narrow group that is both adapted to contaminant toxicity and able to compete with indigenous AMF species.

Contrasting the community structure of arbuscular mycorrhizal fungi from hydrocarbon-contaminated and uncontaminated soils following willow (Salix spp. L.) planting.

Science.gov (United States)

Hassan, Saad El-Din; Bell, Terrence H; Stefani, Franck O P; Denis, David; Hijri, Mohamed; St-Arnaud, Marc

2014-01-01

Phytoremediation is a potentially inexpensive alternative to chemical treatment of hydrocarbon-contaminated soils, but its success depends heavily on identifying factors that govern the success of root-associated microorganisms involved in hydrocarbon degradation and plant growth stimulation. Arbuscular mycorrhizal fungi (AMF) form symbioses with many terrestrial plants, and are known to stimulate plant growth, although both species identity and the environment influence this relationship. Although AMF are suspected to play a role in plant adaptation to hydrocarbon contamination, their distribution in hydrocarbon-contaminated soils is not well known. In this study, we examined how AMF communities were structured within the rhizosphere of 11 introduced willow cultivars as well as unplanted controls across uncontaminated and hydrocarbon-contaminated soils at the site of a former petrochemical plant. We obtained 69 282 AMF-specific 18S rDNA sequences using 454-pyrosequencing, representing 27 OTUs. Contaminant concentration was the major influence on AMF community structure, with different AMF families dominating at each contaminant level. The most abundant operational taxonomic unit in each sample represented a large proportion of the total community, and this proportion was positively associated with increasing contamination, and seemingly, by planting as well. The most contaminated soils were dominated by three phylotypes closely related to Rhizophagus irregularis, while these OTUs represented only a small proportion of sequences in uncontaminated and moderately contaminated soils. These results suggest that in situ inoculation of AMF strains could be an important component of phytoremediation treatments, but that strains should be selected from the narrow group that is both adapted to contaminant toxicity and able to compete with indigenous AMF species.

Chlorine inactivation of fungal spores on cereal grains.

Science.gov (United States)

Andrews, S; Pardoel, D; Harun, A; Treloar, T

1997-04-01

Although 0.4% chlorine for 2 min has been recommended for surface disinfection of food samples before direct plating for fungal enumeration, this procedure may not be adequate for highly contaminated products. The effectiveness of a range of chlorine solutions was investigated using barley samples artificially contaminated with four different concentrations of Aspergillus flavus. A. niger, A. ochraceus, Eurotium repens, Penicillium brevicompactum P. chrysogenum and Cladosporium cladosporioides. At initial contamination levels greater than 10(4)/g, 0.4% chlorine did not inactivate sufficient spores to produce less than 20% contamination. Of the test fungi, ascospores of E. repens were the most resistant to chlorine inactivation, whereas the conidia of C. cladosporioides were the most sensitive. Rinsing the samples with 70% ethanol improved the effectiveness of the recommended surface disinfection procedure. However, some ethanol appears to permeate into the grains and may inactivate sensitive internal fungi, although a minimal effect only was observed on wheat infected with Alternaria.

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

Ecological risk assessment of a site contaminated with petroleum hydrocarbons

International Nuclear Information System (INIS)

Starodub, M.E.; Feniak, N.A.; Willes, R.F.; Moore, C.E.; Mucklow, L.

1995-01-01

The aquatic and terrestrial health risks associated with petroleum contamination on a decommissioned military base, contaminated with products ranging from Bunker C oil to aviation fuel, were assessed using a methodology whereby an analytical measurement of total petroleum hydrocarbons (TPH) could be correlated with compositional characterization and thus with toxicity. The constituents of petroleum hydrocarbon contamination represent wide ranges of physical-chemical properties, environmental fate, and toxicity. The composition of TPH can vary greatly, dependent on the sources or fuel types and the interaction of age as well as site- and chemical-specific characteristics in determining the impact of weathering processes. Therefore, a bulk sum analysis of TPH cannot be related to toxicity without characterization of its composition and association of the constituents, and therefore composition, with actual toxicity data. To address this need, the constituents of TPH were represented by surrogate chemicals, with selection based on structure-activity relationships and available toxicity data. Toxicological profiles were developed from governmental regulations and on the published literature for both the aquatic and terrestrial media. Risk characterization consisted of a comparison of water concentration limits and exposure limits, developed for each surrogate, to estimated surrogate concentrations throughout the site. The concentrations of surrogates were extrapolated from TPH composition characterization analyses, conducted at a select number of sampling locations, to bulk sum analyses of TPH at related sampling locations

Unique problems of hydrocarbon contamination for ports

International Nuclear Information System (INIS)

Rice, D.W.

1991-01-01

Since the early 1900s, port facilities in the United States have been involved in the import and export of petroleum products. The WORLDPORT L.A. is a 7,000 acre land and water area that is administered by the Department of The City of Los Angeles under a tidelands grant from the State of California for the purposes of commerce, navigation, and fisheries. Over half of the oil-refining of California lies within 20 miles of WORLDPORT L.A. It is therefore not surprising that the port is a major hub for the handling of crude oil and petroleum products, including gasoline, aviation gas/jet fuel, and marine fuels. This paper reports that it is also not surprising that port facilities, given their long history of handling petroleum products, contain areas where soils and groundwater are contaminated with hydrocarbons. This contamination is localized but can be extensive. Petroleum and petrochemical products are handled at terminal facilities that are leased to oil companies

Fluorescence in situ hybridization (CARD-FISH) of microorganisms in hydrocarbon contaminated aquifer sediment samples.

Science.gov (United States)

Tischer, Karolin; Zeder, Michael; Klug, Rebecca; Pernthaler, Jakob; Schattenhofer, Martha; Harms, Hauke; Wendeberg, Annelie

2012-12-01

Groundwater ecosystems are the most important sources of drinking water worldwide but they are threatened by contamination and overexploitation. Petroleum spills account for the most common source of contamination and the high carbon load results in anoxia and steep geochemical gradients. Microbes play a major role in the transformation of petroleum hydrocarbons into less toxic substances. To investigate microbial populations at the single cell level, fluorescence in situ hybridization (FISH) is now a well-established technique. Recently, however, catalyzed reporter deposition (CARD)-FISH has been introduced for the detection of microbes from oligotrophic environments. Nevertheless, petroleum contaminated aquifers present a worst case scenario for FISH techniques due to the combination of high background fluorescence of hydrocarbons and the presence of small microbial cells caused by the low turnover rates characteristic of groundwater ecosystems. It is therefore not surprising that studies of microorganisms from such sites are mostly based on cultivation techniques, fingerprinting, and amplicon sequencing. However, to reveal the population dynamics and interspecies relationships of the key participants of contaminant degradation, FISH is an indispensable tool. In this study, a protocol for FISH was developed in combination with cell quantification using an automated counting microscope. The protocol includes the separation and purification of microbial cells from sediment particles, cell permeabilization and, finally, CARD-FISH in a microwave oven. As a proof of principle, the distribution of Archaea and Bacteria was shown in 60 sediment samples taken across the contaminant plume of an aquifer (Leuna, Germany), which has been heavily contaminated with several ten-thousand tonnes of petroleum hydrocarbons since World War II. Copyright © 2012 Elsevier GmbH. All rights reserved.

Contamination by heavy metals and petroleum hydrocarbons: a threat to mangroves

Directory of Open Access Journals (Sweden)

Thaís dos Santos Alencar

2016-12-01

Full Text Available The mangrove ecosystem is one of the most productive ecosystems on the planet with relevant ecological importance. It offers several services such as protection of the coastal region, immobilization of contaminants, as it is a food source and refuge for various organisms. However, mangroves are threatened by human activities. Oil spills in areas close to mangroves, for example, are potential sources for the entry of contaminants such as heavy metals and hydrocarbons. Among other sources of threat, we list industrial waste and sewage, mining and fertilizer use. When they reach the mangroves, these contaminants may cause several negative effects and affect its balance.

The effect of fuel and chlorinated hydrocarbons on a vapor phase carbon adsorption system

International Nuclear Information System (INIS)

Crawford, W.J.; Cheney, J.L.; Taggart, D.B.

1995-01-01

A soil vapor extraction (SVE) system installed at the South Tacoma Well 12A Superfund Site was designed to recover 1,2-dichloroethylene (DCE), trichloroethylene (TCE), tetrachloroethylene (PCE), and 1,1,2,2-tetrachloroethane (1,1,2,2-TCA) from the vadose zone. The basic system consisted of twenty-two extraction wells, three centrifugal blowers, and three carbon adsorbers. The carbon adsorbers were regenerated on site by steam stripping. The mixture of steam and stripped organics was condensed and then decanted to separate the water from the organic phase. The recovered water was air stripped to remove the dissolved organics prior to discharge to the city storm sewer. The recovered organic phase was then shipped off site for thermal destruction. Previous reports described operating difficulties with the decanter, and air strippers. Sampling and analyses were performed which identified the problem as the simultaneous recovery of unexpected fuel hydrocarbons in addition to the solvents. Recovery of fuels resulted in a light phase in the decanter in addition to the water and heavy solvent phases. This required redesign of the decanter to handle the third phase. The effectiveness of desorption of the carbon beds by steam stripping gradually decreased as the remediation progressed into the second year of operation. Samples were collected from the carbon beds to evaluate the effect of the fuel and chlorinated hydrocarbons on the activated carbon. This report describes the results of these analyses. The data indicated that both 1,1,2,2-TCA and fuel hydrocarbons in the C-9 to C-24 range remained in the carbon beds after steam regeneration in sufficient quantities to require replacing the carbon

Fingerprinting of petroleum hydrocarbons (PHC) and other biogenic organic compounds (BOC) in oil-contaminated and background soil samples.

Science.gov (United States)

Wang, Zhendi; Yang, C; Yang, Z; Hollebone, B; Brown, C E; Landriault, M; Sun, J; Mudge, S M; Kelly-Hooper, F; Dixon, D G

2012-09-01

Total petroleum hydrocarbons (TPH) or petroleum hydrocarbons (PHC) are one of the most widespread soil contaminants in Canada, the United States and many other countries worldwide. Clean-up of PHC-contaminated soils costs the Canadian economy hundreds of millions of dollars annually. In Canada, most PHC-contaminated site evaluations are based on the methods developed by the Canadian Council of the Ministers of the Environment (CCME). However, the CCME method does not differentiate PHC from BOC (the naturally occurring biogenic organic compounds), which are co-extracted with petroleum hydrocarbons in soil samples. Consequently, this could lead to overestimation of PHC levels in soil samples. In some cases, biogenic interferences can even exceed regulatory levels (300 μg g(-1) for coarse soils and 1300 μg g(-1) for fine soils for Fraction 3, C(16)-C(34) range, in the CCME Soil Quality Level). Resulting false exceedances can trigger unnecessary and costly cleanup or remediation measures. Therefore, it is critically important to develop new protocols to characterize and quantitatively differentiate PHC and BOC in contaminated soils. The ultimate objective of this PERD (Program of Energy Research and Development) project is to correct the misconception that all detectable hydrocarbons should be regulated as toxic petroleum hydrocarbons. During 2009-2010, soil and plant samples were collected from over forty oil-contaminated and paired background sites in various provinces. The silica gel column cleanup procedure was applied to effectively remove all target BOC from the oil-contaminated sample extracts. Furthermore, a reliable GC-MS method in combination with the derivatization technique, developed in this laboratory, was used for identification and characterization of various biogenic sterols and other major biogenic compounds in these oil-contaminated samples. Both PHC and BOC in these samples were quantitatively determined. This paper reports the characterization

Analyzing geophysical signature of a hydrocarbon-contaminated soil using geoelectrical surveys

Czech Academy of Sciences Publication Activity Database

Koroma, Sylvester; Arrato, A.; Godio, A.

2015-01-01

Roč. 74, č. 4 (2015), s. 2937-2948 ISSN 1866-6280 Institutional support: RVO:68145535 Keywords : electrical conductivity * induced polarization * hydrocarbon-contaminated site * biodegradation Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.765, year: 2014 http://link.springer.com/article/10.1007/s12665-015-4326-6

Evaluation of organic contamination in urban groundwater surrounding a municipal landfill, Zhoukou, China.

Science.gov (United States)

Han, D M; Tong, X X; Jin, M G; Hepburn, Emily; Tong, C S; Song, X F

2013-04-01

This paper investigates the organic pollution status of shallow aquifer sediments and groundwater around Zhoukou landfill. Chlorinated aliphatic hydrocarbons, monocylic aromatic hydrocarbons, halogenated aromatic hydrocarbons, organochlorine pesticides and other pesticides, and polycyclic aromatic hydrocarbons (PAHs) have been detected in some water samples. Among the detected eleven PAHs, phenanthrene, fluorine, and fluoranthene are the three dominant in most of the groundwater samples. Analysis of groundwater samples around the landfill revealed concentrations of PAHs ranging from not detected to 2.19 μg/L. The results show that sediments below the waste dump were low in pollution, and the shallow aquifer, at a depth of 18-30 m, was heavily contaminated, particularly during the wet season. An oval-shaped pollution halo has formed, spanning 3 km from west to east and 2 km from south to north, and mainly occurs in groundwater depths of 2-4 m. For PAH source identification, both diagnostic ratios of selected PAHs and principal component analysis were studied, suggesting mixed sources of pyro- and petrogenic derived PAHs in the Zhoukou landfill. Groundwater table fluctuations play an important role in the distribution of organic pollutants within the shallow aquifer. A conceptual model of leachate migration in the Quaternary aquifers surrounding the Zhoukou landfill has been developed to describe the contamination processes based on the major contaminant (PAHs). The groundwater zone contaminated by leachate has been identified surrounding the landfill.

Synergistic degradation of chlorinated hydrocarbons with microorganisms and zero valent iron

Science.gov (United States)

Schöftner, Philipp; Summer, Dorothea; Leitner, Simon; Watzinger, Andrea; Wimmer, Bernhard; Reichenauer, Thomas

2016-04-01

Sites contaminated with chlorinated hydrocarbons (CHC) are located mainly within build-up regions. Therefore in most cases only in-situ technologies without excavation of soil material can be used for remediation. This project examines a novel in-situ remediation method, in which the biotic degradation via bacteria is combined with abiotic degradation via zero-valent iron particles (ZVI). ZVI particles are injected into the aquifer where CHC-molecules are reductively dechlorinated. However Fe0 is also oxidized by reaction with water leading to generation of H2 without any CHC degradation. To achieve biotic degradation often strictly anaerobic strains of the bacteria Dehalococcoides are used. These bacteria can dechlorinate CHC by utilizing H2. By combining these processes the H2, produced during the anaerobic corrosion of Fe0, could be used by bacteria for further CHC degradation. Therefore the amount of used Fe0 and as a consequence also remediation costs could be reduced. Additionally the continuous supply of H2 could make the bacterial degradation more controllable. Different Fe0 particles (nano- and micro-scale) were tested for their perchloroethene (PCE) degradation rate and H2 production rate in microcosms. PCE-degradation rate by different bacterial cultures was investigated in the same microcosm system. In course of these experiments the 13C enrichment factors of the PCE degradation of the different particles and cultures were determined to enable the differentiation of biotic and abiotic degradation. Preliminary results showed, that the nano-scale particles reacted faster with PCE and water than their micro-scaled counterparts. The PCE degradation via micro-scaled particles lead to 13C enrichment factors in the range of -3,6 ‰ ± 0,6 to -9,5 ‰ ± 0,2. With one of the examined bacterial cultures a fast reduction of PCE to ethene was observed. Although PCE and TCE were completely degraded by this culture the metabolites DCE and VC could still be detected

Development of an analysis method for determining chlorinated hydrocarbons in marine sediments and suspended matter giving particular consideration to supercritical fluid extraction; Entwicklung eines Analysenverfahrens zur Bestimmung von chlorierten Kohlenwasserstoffen in marinen Sedimenten und Schwebstoffen unter besonderer Beruecksichtigung der ueberkritischen Fluidextraktion

Energy Technology Data Exchange (ETDEWEB)

Sterzenbach, D.

1997-11-01

The purpose of the present study was to develop an analysis method for chlorinate hydrocarbons in marine environments using supercritical fluid extraction (SFE) instead of conventional approaches. In order to apply this extraction method the available SFE device had to be extended and all the individual steps of the analysis method had to be optimised and adapted. As chlorinated hydrocarbons only occur at very low concentrations in marine environments (ppm to ppt range) the analysis method had to be extremely sensitive. High sensitivity, in town, is generally associated with a high susceptibility of an analysis method to faults through contamination or losses. This meant that the entire method and all its individual steps had to scrutinised for such weak points and improved where necessary. A method for sampling suspended matter in marine environments had to be developed which permits efficient separation of the smallest possible particles from seawater. The designated purpose of the developed analysis method is to deal with topical aspects of marine chemistry relating to sources, transport, distribution, and the fate of chlorinated hydrocarbons in marine environments. (orig.) [Deutsch] Ziel der vorliegenden Arbeit ist, ein Analysenverfahren fuer chlorierte Kohlenwasserstoffe in der marinen Umwelt zu entwickeln. Dabei soll die ueberkritische Fluidextraktion (SFE) anstelle herkoemmlicher Verfahren eingesetzt werden. Fuer die Anwendung dieser Extraktionsmethode ist es erforderlich, das zur Verfuegung stehende SFE-Geraet zu erweitern und saemtliche Teilschritte des Analysenverfahrens zu optimieren und auf diese Methode abzustimmen. Der Umstand, dass die chlorierten Kohlenwasserstoffe nur in sehr geringen Konzentrationen in der marinen Umwelt vorkommen (ppm- bis ppt-Bereich), erfordert eine sehr hohe Empfindlichkeit des Analysenverfahrens. Eine hohe Empfindlichkeit bedingt eine grosse Stoeranfaelligkeit des Analysenverfahrens durch Kontaminationen oder Verluste. Aus

Inhibition of hydrocarbon bioremediation by lead in a crude oil-contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Al-Saleh, E.S.; Obuekwe, C. [Kuwait University (Kuwait). Department of Biological Sciences, Microbiology Program

2005-07-01

Analyses of soil samples revealed that the level of lead (total or bioavailable) was three-fold greater in crude oil contaminated than in uncontaminated Kuwaiti soils. Investigation of the possible inhibitory effect of lead on hydrocarbon degradation by the soil microbiota showed that the number of hydrocarbon-degrading bacteria decreased with increased levels of lead nitrate added to soil samples, whether oil polluted or not. At 1.0 mg lead nitrate g{sup -1} dry soil, the number of degraders of hexadecane, naphthalene and crude oil declined by 14%, 23% and 53%, respectively. In a similar manner, the degradation and mineralization of different hydrocarbons decreased with increased lead content in cultures, although the decreases were not significantly different (P>0.05). The dehydrogenase activities of soil samples containing hydrocarbons as substrates also declined with an increase in the lead content of soil samples. (author)

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.

Microbial activity in an acid resin deposit: Biodegradation potential and ecotoxicology in an extremely acidic hydrocarbon contamination

International Nuclear Information System (INIS)

Kloos, Karin; Schloter, Michael; Meyer, Ortwin

2006-01-01

Acid resins are residues produced in a recycling process for used oils that was in use in the forties and fifties of the last century. The resin-like material is highly contaminated with mineral oil hydrocarbons, extremely acidic and co-contaminated with substituted and aromatic hydrocarbons, and heavy metals. To determine the potential for microbial biodegradation the acid resin deposit and its surroundings were screened for microbial activity by soil respiration measurements. No microbial activity was found in the core deposit. However, biodegradation of hydrocarbons was possible in zones with a lower degree of contamination surrounding the deposit. An extreme acidophilic microbial community was detected close to the core deposit. With a simple ecotoxicological approach it could be shown that the pure acid resin that formed the major part of the core deposit, was toxic to the indigenous microflora due to its extremely low pH of 0-1. - Acidity is the major toxic factor of the extremely hydrophobic and acidic mixed contamination found in an acid resin deposit

Decontamination of a drinking water pipeline system contaminated with adenovirus and Escherichia coli utilizing peracetic acid and chlorine.

Science.gov (United States)

Kauppinen, Ari; Ikonen, Jenni; Pursiainen, Anna; Pitkänen, Tarja; Miettinen, Ilkka T

2012-09-01

A contaminated drinking water distribution network can be responsible for major outbreaks of infections. In this study, two chemical decontaminants, peracetic acid (PAA) and chlorine, were used to test how a laboratory-scale pipeline system can be cleaned after simultaneous contamination with human adenovirus 40 (AdV40) and Escherichia coli. In addition, the effect of the decontaminants on biofilms was followed as heterotrophic plate counts (HPC) and total cell counts (TCC). Real-time quantitative polymerase chain reaction (qPCR) was used to determine AdV40 and plate counting was used to enumerate E. coli. PAA and chlorine proved to be effective decontaminants since they decreased the levels of AdV40 and E. coli to below method detection limits in both water and biofilms. However, without decontamination, AdV40 remained present in the pipelines for up to 4 days. In contrast, the concentration of cultivable E. coli decreased rapidly in the control pipelines, implying that E. coli may be an inadequate indicator for the presence of viral pathogens. Biofilms responded to the decontaminants by decreased HPCs while TCC remained stable. This indicates that the mechanism of pipeline decontamination by chlorine and PAA is inactivation rather than physical removal of microbes.

Treatment of petroleum-hydrocarbon contaminated soils using hydrogen peroxide oxidation catalyzed by waste basic oxygen furnace slag

International Nuclear Information System (INIS)

Tsai, T.T.; Kao, C.M.

2009-01-01

The contamination of subsurface soils with petroleum hydrocarbons is a widespread environmental problem. The objective of this study was to evaluate the potential of applying waste basic oxygen furnace slag (BOF slag) as the catalyst to enhance the Fenton-like oxidation to remediate fuel oil or diesel contaminated soils. The studied controlling factors that affect the removal efficiency of petroleum hydrocarbons included concentrations of H 2 O 2 , BOF slag dosages, types of petroleum hydrocarbons (e.g., fuel oil and diesel), and types of iron mineral. Experimental results indicate that oxidation of petroleum hydrocarbon via the Fenton-like process can be enhanced with the addition of BOF slag. Results from the X-ray powder diffraction analysis reveal that the major iron type of BOF slag/sandy loam system was iron mineral (e.g., α-Fe 2 O 3 and α-FeOOH). Approximately 76% and 96% of fuel oil and diesel removal were observed (initial total petroleum hydrocarbon (TPH) concentration = 10,000 mg kg -1 ), respectively, with the addition of 15% of H 2 O 2 and 100 g kg -1 of BOF slag after 40 h of reaction. Because BOF slag contains extractable irons such as amorphous iron and soluble iron, it can act as an iron sink to supply iron continuously for Fenton-like oxidation. Results demonstrate that Fenton-like oxidation catalyzed by BOF slag is a potential method to be able to remediate petroleum-hydrocarbon contaminated soils efficiently and effectively.

Development of a multistrain bacterial bioreporter platform for the monitoring of hydrocarbon contaminants in marine environments

NARCIS (Netherlands)

Tecon, R.; Beggah, S.; Czechowska, K.; Sentchilo, V.; Chronopoulou, P.M.; McGenity, T.J.; van der Meer, J.R.

2010-01-01

Petroleum hydrocarbons are common contaminants in marine and freshwater aquatic habitats, often occurring as a result of oil spillage. Rapid and reliable on-site tools for measuring the bioavailable hydrocarbon fractions, i.e., those that are most likely to cause toxic effects or are available for

Uptake of Total Petroleum Hydrocarbon (TPH) and Polycyclic Aromatic Hydrocarbons (PAHs) by Oryza sativa L. Grown in Soil Contaminated with Crude Oil.

Science.gov (United States)

Patowary, Rupshikha; Patowary, Kaustuvmani; Devi, Arundhuti; Kalita, Mohan Chandra; Deka, Suresh

2017-01-01

The purpose of this study was to determine whether total petroleum hydrocarbon (TPH) and polycyclic aromatic hydrocarbons (PAHs) present in crude oil contaminated sites are transferred to roots, shoots and finally the grains of rice crops (Oryza sativa L.) grown in those sites. Soil was artificially contaminated with crude oil at concentrations of 0, 1000, 5000, 10,000, and 15,000 mg/kg, followed by planting of rice seedlings. After harvest, TPH in plant samples were measured, and it was determined that the uptake of TPH by the plants gradually increased as the concentration of oil in soil increased. Further, from GC-MS analysis, it was observed that PAHs including naphthalene and phenanthrene bioaccumulated in rice plant parts. Vital physico-chemical properties of soil were also altered due to crude oil contamination. Our study revealed that rice plants grown in crude oil polluted sites can uptake TPH including PAHs, thus emphasising the importance of prior investigation of soil condition before cultivation of crops.

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

Ecotoxicity monitoring of hydrocarbon-contaminated soil during bioremediation: a case study

Czech Academy of Sciences Publication Activity Database

Hubálek, Tomáš; Vosáhlová, S.; Matějů, V.; Kováčová, Nora; Novotný, Čeněk

2007-01-01

Roč. 52, č. 1 (2007), s. 1-7 ISSN 0090-4341 R&D Projects: GA MŠk LN00B030; GA AV ČR KJB600200514 Institutional research plan: CEZ:AV0Z50200510 Keywords : bioremediation * ecotoxicity * hydrocarbon-contaminated soil Subject RIV: EE - Microbiology, Virology Impact factor: 1.620, year: 2007

Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site

Energy Technology Data Exchange (ETDEWEB)

Akbari, Ali; Ghoshal, Subhasis, E-mail: subhasis.ghoshal@mcgill.ca

2014-09-15

Highlights: • Aeration and moisture addition alone caused extensive hydrocarbon biodegradation. • 30-day slurry reactor remediation endpoints attained in 385 days in biopiles. • High nitrogen concentrations inhibited hydrocarbon degradation. • Inhibition of biodegradation linked to lack of shifts in soil microbial community. - Abstract: Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16–C34) in a pilot-scale biopile experiment conducted at 15 °C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16–C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day{sup −1} in biopile tank compared to 0.11 day{sup −1} in slurry bioreactors for C16–C34 hydrocarbons, the biodegradation extents for this fraction

Enhanced thermal conduction -- An alternative solution for removing a broad range of hydrocarbons from contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bova, J.C.

1999-07-01

This paper presents an overview of Enhanced Thermal Conduction (ETC), an ex-situ soil remediation process. A review of a practical demonstration of this process which was conducted by Woodward-Clyde Consultants to determine the capability of the technology for remediating soils from gasworks sites that have been contaminated with petroleum hydrocarbons, polynuclear hydrocarbons (PAHs) and cyanide is also presented in this paper. Projections for using this process to treat soils contaminated with other hazardous materials such as TCE PCE and PCB's are discussed as well.

An investigation into the activation and deactivation of chlorinated hydrocarbons to genotoxins in metabolically competent human cells.

Science.gov (United States)

Doherty, A T; Ellard, S; Parry, E M; Parry, J M

1996-05-01

We have investigated the induction of micronuclei by 15 chlorinated hydrocarbons in the cytochalasin B-blocked micronucleus assay utilizing genetically engineered cell lines. The human lymphoblastoid cell line AHH-1, with native cytochrome CYP1A1 activity, the MCL-5 cell line, which stably expresses cDNAs encoding human CYP1A2, 2A6, 3A4, 2E1 and microsomal epoxide hydrolase, and the h2E1 cell line, containing a cDNA for CYP2E1, were used in this study. We have demonstrated the induction of kinetochore-positive micronuclei by two chlorinated solvents, 2,3-dichlorobutane and 1,1, 2-trichloroethane, in the metabolically competent cell lines MCL-5 and h2E1. The MCL-5 and h2E1 cell lines have in addition shown the capacity to produce metabolites in the presence of methylene chloride, carbon tetrachloride, 1,2,3-trichloropropane, tetrachloroethylene, toluene and n-hexane, wich yield elevated micronucleus frequencies compared with the parental cell line AHH-1. Hexachloroethane failed to induce micronuclei in any of the cell lines and 1,2-dichloroethane and 1-chlorohexane induced micronuclei without the requirement for metabolic activation in all three cell lines. The MCL-5 cell line exhibited reduced micronucleus frequencies compared with the AHH-1 and h2E1 cell lines following exposure to 1,2-dichloroethylene, 1,3-dichloropropane, 1,1, 1-trichloroethane and 1,2,3-trichloropropane. The methodology used has shown the ability of metabolically competent cell lines expressing cDNAs encoding the cytochrome P450 isoenzymes to metabolize halogenated hydrocarbons to genotoxic species, including both clastogens and aneugens. The biotransformation of chemicals to aneugenic species has not previously been demonstrated.

A method for predicting the extent of petroleum hydrocarbon biodegradation in contaminated soils

International Nuclear Information System (INIS)

Huesemann, M.H.

1994-01-01

A series of solid- and slurry-phase soil bioremediation experiments involving different crude oils and refined petroleum products were performed to investigate the factors which affect the maximum extent of total petroleum hydrocarbon (TPH) biodegradation. The authors used a comprehensive petroleum hydrocarbon characterization procedure involving group-type separation analyses, boiling-point distributions, and hydrocarbon typing by field ionization mass spectroscopy. Initial and final concentrations of specified hydrocarbon classes were determined in each of seven different bioremediation treatments. Generally, they found that the degree of TPH biodegradation was affected mainly by the type of hydrocarbons in the contaminant matrix. In contrast, the influence of experimental variables such as soil type, fertilizer concentrations, microbial plate counts, and treatment type (slurry versus landfarming) on the overall extent of TPH biodegradation was insignificant. Based on these findings, a predictive algorithm was developed to estimate the extent of TPH biodegradation from the average reduction of 86 individual hydrocarbon classes and their respective initial concentrations. Model predictions for gravimetric TPH removals were in close agreement with analytical results from two independent laboratories

Metabolic and phylogenetic analysis of microbial communities during phytoremediation of soil contaminated with weathered hydrocarbons and heavy metals.

Science.gov (United States)

Palmroth, Marja R T; Koskinen, Perttu E P; Kaksonen, Anna H; Münster, Uwe; Pichtel, John; Puhakka, Jaakko A

2007-12-01

In the current study, the microbial ecology of weathered hydrocarbon and heavy metal contaminated soil undergoing phytoremediation was studied. The relationship of functional diversity, measured as carbon source utilisation in Biolog plates and extracellular enzymatic activities, and genetic diversity of bacteria was evaluated. Denaturing gradient gel electrophoresis was used for community analyses at the species level. Bulk soil and rhizosphere soil from pine and poplar plantations were analysed separately to determine if the plant rhizosphere impacted hydrocarbon degradation. Prevailing microbial communities in the field site were both genetically and metabolically diverse. Furthermore, both tree rhizosphere and fertilisation affected the compositions of these communities and increased activities of extracellular aminopeptidases. In addition, the abundance of alkane hydroxylase and naphthalene dioxygenase genes in the communities was low, but the prevalence of these genes was increased by the addition of bioavailable hydrocarbons. Tree rhizosphere communities had greater hydrocarbon degradation potential than those of bulk soil. Hydrocarbon utilising communities were dominated generally by the species Ralstonia eutropha and bacteria belonging to the genus Burkholderia. Despite the presence of viable hydrocarbon-degrading microbiota, decomposition of hydrocarbons from weathered hydrocarbon contaminated soil over four years, regardless of the presence of vegetation, was low in unfertilised soil. Compost addition enhanced the removal of hydrocarbons.

Improvement of phytoremediation of an aged petroleum hydrocarbon-contaminated soil by Rhodococcus erythropolis CD 106 strain.

Science.gov (United States)

Płociniczak, Tomasz; Fic, Ewa; Pacwa-Płociniczak, Magdalena; Pawlik, Małgorzata; Piotrowska-Seget, Zofia

2017-07-03

The aim of this study was to assess the impact of soil inoculation with the Rhodococcus erythropolis CD 106 strain on the effectiveness of the phytoremediation of an aged hydrocarbon-contaminated [approx. 1% total petroleum hydrocarbon (TPH)] soil using ryegrass (Lolium perenne). The introduction of CD 106 into the soil significantly increased the biomass of ryegrass and the removal of hydrocarbons in planted soil. The fresh weight of the shoots and roots of plants inoculated with CD 106 increased by 49% and 30%, respectively. After 210 days of the experiment, the concentration of TPH was reduced by 31.2%, whereas in the planted, non-inoculated soil, it was reduced by 16.8%. By contrast, the concentration of petroleum hydrocarbon decreased by 18.7% in non-planted soil bioaugmented with the CD 106 strain. The rifampicin-resistant CD 106 strain survived after inoculation into soil and was detected in the soil during the entire experimental period, but the number of CD 106 cells decreased constantly during the enhanced phytoremediation and bioaugmentation experiments. The plant growth-promoting and hydrocarbon-degrading properties of CD 106, which are connected with its long-term survival and limited impact on autochthonous microflora, make this strain a good candidate for improving the phytoremediation efficiency of soil contaminated with hydrocarbons.

The use of field redox measurements in assessing remediation of ground water containing petroleum hydrocarbons and chlorinated organic compounds

International Nuclear Information System (INIS)

Warner, S.D.; Gallinatti, J.D.; Honniball, J.H.

1995-01-01

Field measurements of the reduction-oxidation (redox) condition of ground water were used to assess the effects of in situ remediation of ground water affected by petroleum hydrocarbons and chlorinated organic compounds at multiple sites in northern California. The redox condition of ground water, traditionally measured quickly and inexpensively using a meter that measures electrode potential (Eh), is a valuable parameter by which to assess the conditions that affect the relative stability of various chemicals in ground water. Although not specific to a given redox couple measurements obtained using the traditional Eh meter give a sense of the relative tendency for a ground water to be reducing or oxidizing by providing a measurement of the system Eh. Two cases demonstrate the use of ground water Eh measurements in assessing the effects of in situ ground water remediation. In the first case, ground water affected by petroleum hydrocarbons-gasoline (TPHg), and benzene, toluene, ethylbenzene, and xylenes (BTEX) (ambient Eh of -100 to +100 millivolts [mv]) was treated by injecting hydrogen peroxide to supply oxygen to the subsurface environment and stimulate microbial activity. The second case involved remediation of ground water containing chlorinated organic compounds. In this case, a subsurface permeable ground water treatment wall containing granular iron was installed across the flow path of the affected ground water. The in situ chemical treatment, which successfully dechlorinates compounds such as trichloroethylene, 1,2-dichloroethylene, and vinyl chloride, caused reducing conditions in the ground water, which resulted in the decrease in ground water Eh from am ambient reading of about -50 mv to about -400 mv

Apparent Contradiction: Psychrotolerant Bacteria from Hydrocarbon-Contaminated Arctic Tundra Soils That Degrade Diterpenoids Synthesized by Trees

Science.gov (United States)

Yu, Zhongtang; Stewart, Gordon R.; Mohn, William W.

2000-01-01

Resin acids are tricyclic terpenoids occurring naturally in trees. We investigated the occurrence of resin acid-degrading bacteria on the Arctic tundra near the northern coast of Ellesmere Island (82°N, 62°W). According to most-probable-number assays, resin acid degraders were abundant (103 to 104 propagules/g of soil) in hydrocarbon-contaminated soils, but they were undetectable (soil) in pristine soils from the nearby tundra. Plate counts indicated that the contaminated and the pristine soils had similar populations of heterotrophs (106 to 107 propagules/g of soil). Eleven resin acid-degrading bacteria belonging to four phylogenetically distinct groups were enriched and isolated from the contaminated soils, and representative isolates of each group were further characterized. Strains DhA-91, IpA-92, and IpA-93 are members of the genus Pseudomonas. Strain DhA-95 is a member of the genus Sphingomonas. All four strains are psychrotolerant, with growth temperature ranges of 4°C to 30°C (DhA-91 and DhA-95) or 4°C to 22°C (IpA-92 and IpA-93) and with optimum temperatures of 15 to 22°C. Strains DhA-91 and DhA-95 grew on the abietanes, dehydroabietic and abietic acids, but not on the pimaranes, isopimaric and pimaric acids. Strains IpA-92 and IpA-93 grew on the pimaranes but not the abietanes. All four strains grew on either aliphatic or aromatic hydrocarbons, which is unusual for described resin acid degraders. Eleven mesophilic resin acid degraders did not use hydrocarbons, with the exception of two Mycobacterium sp. strains that used aliphatic hydrocarbons. We conclude that hydrocarbon contamination in Arctic tundra soil indirectly selected for resin acid degraders, selecting for hydrocarbon degraders that coincidentally use resin acids. Psychrotolerant resin acid degraders are likely important in the global carbon cycle and may have applications in biotreatment of pulp and paper mill effluents. PMID:11097882

Efficiency of lipopeptide biosurfactants in removal of petroleum hydrocarbons and heavy metals from contaminated soil.

Science.gov (United States)

Singh, Anil Kumar; Cameotra, Swaranjit Singh

2013-10-01

This study describes the potential application of lipopeptide biosurfactants in removal of petroleum hydrocarbons and heavy metals from the soil samples collected from industrial dumping site. High concentrations of heavy metals (like iron, lead, nickel, cadmium, copper, cobalt and zinc) and petroleum hydrocarbons were present in the contaminated soil samples. Lipopeptide biosurfactant, consisting of surfactin and fengycin was obtained from Bacillus subtilis A21. Soil washing with biosurfactant solution removed significant amount of petroleum hydrocarbon (64.5 %) and metals namely cadmium (44.2 %), cobalt (35.4 %), lead (40.3 %), nickel (32.2 %), copper (26.2 %) and zinc (32.07 %). Parameters like surfactant concentration, temperature, agitation condition and pH of the washing solution influenced the pollutant removing ability of biosurfactant mixture. Biosurfactant exhibited substantial hydrocarbon solubility above its critical micelle concentration. During washing, 50 % of biosurfactant was sorbed to the soil particles decreasing effective concentration during washing process. Biosurfactant washed soil exhibited 100 % mustard seed germination contradictory to water washed soil where no germination was observed. The results indicate that the soil washing with mixture of lipopeptide biosurfactants at concentrations above its critical micelle concentration can be an efficient and environment friendly approach for removing pollutants (petroleum hydrocarbon and heavy metals) from contaminated soil.

Electrical resistivity and induced polarization tomography in identifying the plume of chlorinated hydrocarbons in sedimentary formation: a case study in Rho (Milan - Italy).

Science.gov (United States)

Cardarelli, Ettore; Di Filippo, Gerardina

2009-09-01

Resistivity and induced polarization surveying were originally developed for mineral exploration but are now finding new applications in the field of environmental and engineering geophysics. The present article reports the results of a geophysical survey performed with the aim of identifying a plume of chlorinated hydrocarbons in sedimentary formations of the Pandania plain. The tested site is characterized by three sand and gravel aquifers containing a quantity of clay particles which influence the overall bulk resistivity and chargeability. According to data obtained using shallow boreholes, mainly dense non-aqueous phase liquids were found as contaminants in the first and second aquifer. The aforementioned geo-electrical methods were applied in both two- and three-dimensional approaches. Steel and copper electrodes were used in the process of field data acquisition and the results of the survey were compared. The geophysical survey revealed some anomalies that could be explained by the presence of dense non-aqueous phase liquids in the soil medium. The concept of normalized chargeability facilitates the interpretation of detected induced polarization anomalies. The shape of the plume was inferred from maps of resistivity and chargeability to a depth of 25 m below the surface of the ground.

Purifying hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Demoulins, H D; Garner, F H

1923-02-07

Hydrocarbon distillates, including natural gases and vapors produced by cracking hydrocarbon oils, are desulfurized etc. by treating the vapor with an aqueous alkaline solution of an oxidizing agent. The hydrocarbons may be previously purified by sulfuric acid. In examples aqueous solutions of sodium or calcium hydrochlorite containing 1.5 to 5.0 grams per liter of available chlorine and sufficient alkali to give an excess of 0.1 percent in the spent reagent are preheated to the temperature of the vapor, and either sprayed or atomized into the vapors near the outlet of the dephlegmator or fractionating tower, or passed in countercurrent to the vapors through one or a series of scrubbers.

Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site.

Science.gov (United States)

Akbari, Ali; Ghoshal, Subhasis

2014-09-15

Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16-C34) in a pilot-scale biopile experiment conducted at 15°C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16-C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day(-1) in biopile tank compared to 0.11 day(-1) in slurry bioreactors for C16-C34 hydrocarbons, the biodegradation extents for this fraction were comparable in these two systems. Copyright © 2014 Elsevier B.V. All rights reserved.

Heat-Activated Persulfate Oxidation of Chlorinated Solvents in Sandy Soil

Directory of Open Access Journals (Sweden)

Jialu Liu

2014-01-01

Full Text Available Heat-activated persulfate oxidative treatment of chlorinated organic solvents containing chlorinated ethenes and ethanes in soil was investigated with different persulfate dosages (20 g/L, 40 g/L, and 60 g/L and different temperatures (30°C, 40°C, and 50°C. Chlorinated organic solvents removal was increased as persulfate concentration increase. The persulfate dosage of 20 g/L with the highest OE (oxidant efficiency value was economically suitable for chlorinated organic solvents removal. The increasing temperature contributed to the increasing depletion of chlorinated organic solvents. Chlorinated ethenes were more easily removed than chlorinated ethanes. Moreover, the persulfate depletion followed the pseudo-first-order reaction kinetics (kps=0.0292 [PS]0+0.0008, R2=0.9771. Heat-activated persulfate appeared to be an effective oxidant for treatment of chlorinated hydrocarbons.

Analyzing Environmental Policies for Chlorinated Solvents with a Model of Markets and Regulations

Science.gov (United States)

1991-01-01

chlorine, fluorine , bromine, and iodine. Another broad term is chlorocarbons (fluorocarbons), which indicates the chlorinated ( fluorinated ) hydrocarbons... varnishes , and lacquers (Wolf, Yazdani, and Yates, 1990b). Process Substitutes. The only process modifications that are available for consumer paint

Treatment of petroleum-hydrocarbon contaminated soils using hydrogen peroxide oxidation catalyzed by waste basic oxygen furnace slag

Energy Technology Data Exchange (ETDEWEB)

Tsai, T.T. [Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Kao, C.M., E-mail: jkao@mail.nsysu.edu.tw [Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China)

2009-10-15

The contamination of subsurface soils with petroleum hydrocarbons is a widespread environmental problem. The objective of this study was to evaluate the potential of applying waste basic oxygen furnace slag (BOF slag) as the catalyst to enhance the Fenton-like oxidation to remediate fuel oil or diesel contaminated soils. The studied controlling factors that affect the removal efficiency of petroleum hydrocarbons included concentrations of H{sub 2}O{sub 2}, BOF slag dosages, types of petroleum hydrocarbons (e.g., fuel oil and diesel), and types of iron mineral. Experimental results indicate that oxidation of petroleum hydrocarbon via the Fenton-like process can be enhanced with the addition of BOF slag. Results from the X-ray powder diffraction analysis reveal that the major iron type of BOF slag/sandy loam system was iron mineral (e.g., {alpha}-Fe{sub 2}O{sub 3} and {alpha}-FeOOH). Approximately 76% and 96% of fuel oil and diesel removal were observed (initial total petroleum hydrocarbon (TPH) concentration = 10,000 mg kg{sup -1}), respectively, with the addition of 15% of H{sub 2}O{sub 2} and 100 g kg{sup -1} of BOF slag after 40 h of reaction. Because BOF slag contains extractable irons such as amorphous iron and soluble iron, it can act as an iron sink to supply iron continuously for Fenton-like oxidation. Results demonstrate that Fenton-like oxidation catalyzed by BOF slag is a potential method to be able to remediate petroleum-hydrocarbon contaminated soils efficiently and effectively.

Electrolysis-driven bioremediation of crude oil-contaminated marine sediments.

Science.gov (United States)

Bellagamba, Marco; Cruz Viggi, Carolina; Ademollo, Nicoletta; Rossetti, Simona; Aulenta, Federico

2017-09-25

Bioremediation is an effective technology to tackle crude oil spill disasters, which takes advantage of the capacity of naturally occurring microorganisms to degrade petroleum hydrocarbons under a range of environmental conditions. The enzymatic process of breaking down oil is usually more rapid in the presence of oxygen. However, in contaminated sediments, oxygen levels are typically too low to sustain the rapid and complete biodegradation of buried hydrocarbons. Here, we explored the possibility to electrochemically manipulate the redox potential of a crude oil-contaminated marine sediment in order to establish, in situ, conditions that are conducive to contaminants biodegradation by autochthonous microbial communities. The proposed approach is based on the exploitation of low-voltage (2V) seawater electrolysis to drive oxygen generation (while minimizing chlorine evolution) on Dimensionally Stable Anodes (DSA) placed within the contaminated sediment. Results, based on a laboratory scale setup with chronically polluted sediments spiked with crude oil, showed an increased redox potential and a decreased pH in the vicinity of the anode of 'electrified' treatments, consistent with the occurrence of oxygen generation. Accordingly, hydrocarbons biodegradation was substantially accelerated (up to 3-times) compared to 'non-electrified' controls, while sulfate reduction was severely inhibited. Intermittent application of electrolysis proved to be an effective strategy to minimize the energy requirements of the process, without adversely affecting degradation performance. Taken as a whole, this study suggests that electrolysis-driven bioremediation could be a sustainable technology for the management of contaminated sediments. Copyright © 2016 Elsevier B.V. All rights reserved.

Petroleum hydrocarbon contaminated sites: a review of investigation and remediation regulations and processes

Energy Technology Data Exchange (ETDEWEB)

Epelbaum, Michel; Claudio, Jair R [Bureau Veritas do Brasil Sociedade Classificadora e Certificadora Ltda., Sao Paulo, SP (Brazil)

1994-12-31

This paper discusses alternatives on remediation of petroleum hydrocarbon contaminated sites which include groundwater remediation techniques and soil remediation techniques. Finally, the work points out some trends of sites remediation in Brazil and abroad. 6 refs., 1 fig., 7 tabs.

Petroleum hydrocarbon contaminated sites: a review of investigation and remediation regulations and processes

Energy Technology Data Exchange (ETDEWEB)

Epelbaum, Michel; Claudio, Jair R. [Bureau Veritas do Brasil Sociedade Classificadora e Certificadora Ltda., Sao Paulo, SP (Brazil)

1993-12-31

This paper discusses alternatives on remediation of petroleum hydrocarbon contaminated sites which include groundwater remediation techniques and soil remediation techniques. Finally, the work points out some trends of sites remediation in Brazil and abroad. 6 refs., 1 fig., 7 tabs.

Organo chlorine pesticides (OCPs) contaminants in sediments from Karachi harbour, Pakistan

International Nuclear Information System (INIS)

Khan, N.; Khan, S.H.; Amjad, S.; Muller, J.; Nizamani, S.; Bhanger, M.I.

2010-01-01

Mangrove swamps, inter tidal mud flats and creeks of backwaters represent main feature of Karachi harbour area. Karachi harbour sediment is under continuous influence of untreated industrial effluents and domestic waste discharged into the Harbour area via Lyari River. Sediment samples from sixteen locations were collected to evaluate the levels of contamination of organo chlorine pesticides (OCPs) in Karachi harbour and adjoining areas. It has been observed that residual concentrations of various organo chlorine pesticides were considerably higher in the semi-enclosed area of the upper Harbour in the vicinity of the discharge point of Lyari River. The residue of DDT mainly its metabolites (DDE and DDD) were widely distributed and have been detected in most of the sediment samples in relatively higher concentrations as compared to other OCPs. The higher levels of the DDTs would attribute to low tidal flushing of the area. The high proportion of pp'-DDE in the most sediment sampled (41-95%) suggested old inputs of DDTs in the environment. Ratio of sigma DDT and DDT was in the range of 0.04 - 0.24 at all locations which also reflects that the discharges of DDT were negligible in the Harbour area. This may be due to the restrictions being implemented on the use of DDTs and Pakistan has also switched over to natural pest control or using safer formulas. The data obtained during the study showed that concentration levels of other pesticides such as HCHs, HCB and Cyclodienes in the sediment were generally lower than the threshold levels known to harm wildlife by OCPs. The results clearly indicate that elevated concentration of organo chlorine pesticides (OCPs) in the marine sediment of Karachi harbour and adjoining area was localized and much lower than the concentrations reported from neighbouring and regional countries which suggests/confirms that the present use of pesticide in Pakistan is environmentally safe. (author)

Degradation kinetics of chlorinated aliphatic hydrocarbons by methane oxidizers naturally-associated with wetland plant roots

Science.gov (United States)

Powell, C. L.; Goltz, M. N.; Agrawal, A.

2014-12-01

Chlorinated aliphatic hydrocarbons (CAHs) are common groundwater contaminants that can be removed from the environment by natural attenuation processes. CAH biodegradation can occur in wetland environments by reductive dechlorination as well as oxidation pathways. In particular, CAH oxidation may occur in vegetated wetlands, by microorganisms that are naturally associated with the roots of wetland plants. The main objective of this study was to evaluate the cometabolic degradation kinetics of the CAHs, cis-1,2-dichloroethene (cisDCE), trichloroethene (TCE), and 1,1,1-trichloroethane (1,1,1TCA), by methane-oxidizing bacteria associated with the roots of a typical wetland plant in soil-free system. Laboratory microcosms with washed live roots investigated aerobic, cometabolic degradation of CAHs by the root-associated methane-oxidizing bacteria at initial aqueous [CH4] ~ 1.9 mg L- 1, and initial aqueous [CAH] ~ 150 μg L- 1; cisDCE and TCE (in the presence of 1,1,1TCA) degraded significantly, with a removal efficiency of approximately 90% and 46%, respectively. 1,1,1TCA degradation was not observed in the presence of active methane oxidizers. The pseudo first-order degradation rate-constants of TCE and cisDCE were 0.12 ± 0.01 and 0.59 ± 0.07 d- 1, respectively, which are comparable to published values. However, their biomass-normalized degradation rate constants obtained in this study were significantly smaller than pure-culture studies, yet they were comparable to values reported for biofilm systems. The study suggests that CAH removal in wetland plant roots may be comparable to processes within biofilms. This has led us to speculate that the active biomass may be on the root surface as a biofilm. The cisDCE and TCE mass losses due to methane oxidizers in this study offer insight into the role of shallow, vegetated wetlands as an environmental sink for such xenobiotic compounds.

Evaluation of Biostimulation (Nutrients) in hydrocarbons contaminated soils by respirometry

International Nuclear Information System (INIS)

Garcia, Erika; Roldan, Fabio; Garzon, Laura

2011-01-01

The biostimulation process was evaluated in a hydrocarbon contaminated soil by respirometry after amendment with inorganic compound fertilizer (ICF) (N: P: K 28:12:7) and simple inorganic salts (SIS) (NH 4 NO 3 and K 2 HPO 4 ). The soil was contaminated with oily sludge (40.000 MgTPH/Kgdw). The oxygen uptake was measured using two respirometers (HACH 2173b and OXITOP PF 600) during thirteen days (n=3). Two treatments (ICF and SIS) and three controls (abiotic, reference substance and without nutrients) were evaluated during the study. Physicochemical (pH, nutrients, and TPH) and microbiological analysis (heterotrophic and hydrocarbon-utilizing microorganisms) were obtained at the beginning and at the end of each assay. Higher respiration rates were recorded in sis and without nutrient control. Results were 802.28 and 850.72- 1 d-1, MgO 2 kgps - 1d i n HACH, while in OXITOP were 936.65 and 502.05 MgO 2 Kgps respectively. These data indicate that amendment of nutrients stimulated microbial metabolism. ICF had lower respiration rates (188.18 and 139.87 MgO 2 kgps - 1d - 1 i n HACH and OXITOP, respectively) as well as counts; this could be attributed to ammonia toxicity.

Intrinsic Anaerobic Bioremediation of Hydrocarbons in Contaminated Subsurface Plumes and Marine Sediments

Science.gov (United States)

Nanny, M. A.; Nanny, M. A.; Suflita, J. M.; Suflita, J. M.; Davidova, I.; Kropp, K.; Caldwell, M.; Philp, R.; Gieg, L.; Rios-Hernandez, L. A.

2001-05-01

In recent years, several classes of petroleum hydrocarbons contaminating subsurface and marine environments have been found susceptible to anaerobic biodegradation using novel mechanisms entirely distinct from aerobic metabolic pathways. For example, the anaerobic decay of toluene can be initiated by the addition of the aryl methyl group to the double bond of fumarate, resulting in a benzylsuccinic acid metabolite. Our work has shown that an analogous mechanism also occurs with ethylbenzene and the xylene isomers, yielding 3-phenyl-1,2-butane dicarboxylic acid and methylbenzylsuccinic acid, respectively. Moreover, these metabolites have been detected in contaminated environments. Most recently, we have identified metabolites resulting from the initial attack of H26- or D26-n-dodecane during degradation by a sulfate-reducing bacterial culture. Using GC-MS, these metabolites were identified as fatty acids that result from C-H or C-D addition across the double bond of fumarate to give dodecylsuccinic acids in which all 26 protons or deuteriums of the parent alkane were retained. Further, when this enrichment culture was challenged with hexane or decane, hexylsuccinic acid or decylsuccinic acid were identified as resulting metabolites. Similarly, the study of an ethylcyclopentane-degrading sulfate-reducing enrichment produced a metabolite, which is consistent with the addition of fumarate to the parent substrate. These novel anaerobic addition products are characterized by similar, distinctive mass spectral (MS) features (ions specific to the succinic acid portion of the molecule) that can potentially be used to probe contaminated environments for evidence of intrinsic remediation of hydrocarbons. Indeed, analyses of water extracts from two gas condensate-contaminated sites resulted in the tentative detection of alkyl- and cycloalkylsuccinic acids ranging from C3 to C9, including ethylcyclopentyl-succinic acid. In water extracts collected from an area underlying a

Effect of hydrocarbon-contaminated fluctuating groundwater on magnetic properties of shallow sediments

Czech Academy of Sciences Publication Activity Database

Ameen, N. N.; Klueglein, N.; Appel, E.; Petrovský, Eduard; Kappler, A.; Leven, C.

2014-01-01

Roč. 58, č. 3 (2014), s. 442-460 ISSN 0039-3169 R&D Projects: GA MŠk(CZ) LG13042 Institutional support: RVO:67985530 Keywords : environmental magnetism * magnetic susceptibility * groundwater table fluctuation * hydrocarbon contamination * magnetite formation Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 0.806, year: 2014

Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

Science.gov (United States)

Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

2015-01-01

Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons. PMID:26339653

Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

Directory of Open Access Journals (Sweden)

Boutheina Gargouri

2015-01-01

Full Text Available Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons.

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

Occurrence, profiles, and toxic equivalents of chlorinated and brominated polycyclic aromatic hydrocarbons in E-waste open burning soils.

Science.gov (United States)

Nishimura, Chiya; Horii, Yuichi; Tanaka, Shuhei; Asante, Kwadwo Ansong; Ballesteros, Florencio; Viet, Pham Hung; Itai, Takaaki; Takigami, Hidetaka; Tanabe, Shinsuke; Fujimori, Takashi

2017-06-01

We conducted this study to assess the occurrence, profiles, and toxicity of chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) and brominated polycyclic aromatic hydrocarbons (Br-PAHs) in e-waste open burning soils (EOBS). In this study, concentrations of 15 PAHs, 26 Cl-PAHs and 14 Br-PAHs were analyzed in EOBS samples. We found that e-waste open burning is an important emission source of Cl-PAHs and Br-PAHs as well as PAHs. Concentrations of total Cl-PAHs and Br-PAHs in e-waste open burning soil samples ranged from 21 to 2800 ng/g and from 5.8 to 520 ng/g, respectively. Compared with previous studies, the mean of total Cl-PAH concentrations of the EOBS samples in this study was higher than that of electronic shredder waste, that of bottom ash, and comparable to fly ash from waste incinerators in Korea and Japan. The mean of total Br-PAH concentrations of the EOBS samples was generally three to four orders of magnitude higher than those in incinerator bottom ash and comparable to incinerator fly ash, although the number of Br-PAH congeners measured differed among studies. We also found that the Cl-PAH and Br-PAH profiles were similar among all e-waste open burning soil samples but differed from those in waste incinerator fly ash. The profiles and principal component analysis results suggested a unique mechanism of Cl-PAH and Br-PAH formation in EOBS. In addition, the Cl-PAHs and Br-PAHs showed high toxicities equivalent to PCDD/Fs measured in same EOBS samples when calculated based on their relative potencies to benzo[a]pyrene. Along with chlorinated and brominated dioxins and PAHs, Cl-PAHs and Br-PAHs are important environmental pollutants to investigate in EOBS. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enzymatic bioremediation of polyaromatic hydrocarbons by fungal consortia enriched from petroleum contaminated soil and oil seeds.

Science.gov (United States)

Balaji, V; Arulazhagan, P; Ebenezer, P

2014-05-01

The present study focuses on fungal strains capable of secreting extracellular enzymes by utilizing hydrocarbons present in the contaminated soil. Fungal strains were enriched from petroleum hydrocarbons contaminated soil samples collected from Chennai city, India. The potential fungi were isolated and screened for their enzyme secretion such as lipase, laccase, peroxidase and protease and also evaluated fungal enzyme mediated PAHs degradation. Total, 21 potential PAHs degrading fungi were isolated from PAHs contaminated soil, which belongs to 9 genera such as Aspergillus, Curvularia, Drechslera, Fusarium, Lasiodiplodia, Mucor Penicillium, Rhizopus, Trichoderma, and two oilseed-associated fungal genera such as Colletotrichum and Lasiodiplodia were used to test their efficacy in degradation of PAHs in polluted soil. Maximum lipase production was obtained with P. chrysogenum, M. racemosus and L. theobromae VBE1 under optimized cultural condition, which utilized PAHs in contaminated soil as sole carbon source. Fungal strains, P. chrysogenum, M. racemosus and L. theobromae VBE1, as consortia, used in the present study were capable of degrading branched alkane isoprenoids such as pristine (C17) and pyrene (C18) present in PAHs contaminated soil with high lipase production. The fungal consortia acts as potential candidate for bioremediation of PAHs contaminated environments.

Influence of soil and hydrocarbon properties on the solvent extraction of high-concentration weathered petroleum from contaminated soils.

Science.gov (United States)

Sui, Hong; Hua, Zhengtao; Li, Xingang; Li, Hong; Wu, Guozhong

2014-05-01

Petroleum ether was used to extract petroleum hydrocarbons from soils collected from six oil fields with different history of exploratory and contamination. It was capable of fast removing 76-94 % of the total petroleum hydrocarbons including 25 alkanes (C11-C35) and 16 US EPA priority polycyclic aromatic hydrocarbons from soils at room temperature. The partial least squares analysis indicated that the solvent extraction efficiencies were positively correlated with soil organic matter, cation exchange capacity, moisture, pH, and sand content of soils, while negative effects were observed in the properties reflecting the molecular size (e.g., molecular weight and number of carbon atoms) and hydrophobicity (e.g., water solubility, octanol-water partition coefficient, soil organic carbon partition coefficient) of hydrocarbons. The high concentration of weathered crude oil at the order of 10(5) mg kg(-1) in this study was demonstrated adverse for solvent extraction by providing an obvious nonaqueous phase liquid phase for hydrocarbon sinking and increasing the sequestration of soluble hydrocarbons in the insoluble oil fractions during weathering. A full picture of the mass distribution and transport mechanism of petroleum contaminants in soils will ultimately require a variety of studies to gain insights into the dynamic interactions between environmental indicator hydrocarbons and their host oil matrix.

Geophysical Monitoring of Hydrocarbon-Contaminated Soils Remediated with a Bioelectrochemical System.

Science.gov (United States)

Mao, Deqiang; Lu, Lu; Revil, André; Zuo, Yi; Hinton, John; Ren, Zhiyong Jason

2016-08-02

Efficient noninvasive techniques are desired for monitoring the remediation process of contaminated soils. We applied the direct current resistivity technique to image conductivity changes in sandbox experiments where two sandy and clayey soils were initially contaminated with diesel hydrocarbon. The experiments were conducted over a 230 day period. The removal of hydrocarbon was enhanced by a bioelectrochemical system (BES) and the electrical potentials of the BES reactors were also monitored during the course of the experiment. We found that the variation in electrical conductivity shown in the tomograms correlate well with diesel removal from the sandy soil, but this is not the case with the clayey soil. The clayey soil is characterized by a larger specific surface area and therefore a larger surface conductivity. In sandy soil, the removal of the diesel and products from degradation leads to an increase in electrical conductivity during the first 69 days. This is expected since diesel is electrically insulating. For both soils, the activity of BES reactors is moderately imaged by the inverted conductivity tomogram of the reactor. An increase in current production by electrochemically active bacteria activity corresponds to an increase in conductivity of the reactor.

Biochemical and Physical Characterization of Petroleum Hydrocarbon Contaminated Soils in Tehran

Directory of Open Access Journals (Sweden)

Mehrdad Cheraghi

2015-07-01

Full Text Available    Contamination of soil was investigated in this study from the Tehran Oil refining Co. of Iran. Fifteen soil samples were collected at several points in the Azimabad, 15 km south of Tehran City, Iran. Samples were collected at depths of 0–30 cm. Control sampleswere prepared to determinebackgroundlevels ofsoil contaminationwithpetroleumhydrocarbonsfor comparison with contaminatedsites. Total petroleum hydrocarbon (TPH and poly-aromatic hydrocarbons (PAH concentrations varied from 101334.0–101367.1 and 25321.1–25876.6 mg kg-1 respectively. The results elevated levels of TPH and PAH contents when compared with the control sample. Soil acidity (low pH of 5.3–5.9 and low electrical conductivity provided evidence of reduced metabolic activities on the affected site.Microbialgrowthrates for bacteria and fungi expressed as colony forming units were 2.62×109 and 4.14×106CFU/g soil, respectively for the contaminated and 5.76×109 and 6.83×106CFU/g soil, for the control treatments respectively. These drastic changes can have impact on the nutrient cycle and prevents the absorption of nutrients by plant root sand lead to a reduction in yield. 

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.

Theory and application of landfarming to remediate polycyclic aromatic hydrocarbons and mineral oil-contaminated sediments: beneficial reuse

NARCIS (Netherlands)

Harmsen, J.; Rulkens, W.H.; Sims, R.C.; Rijtema, P.E.; Zweers, A.J.

2007-01-01

When applying landfarming for the remediation of contaminated soil and sediment, a fraction of the soil-bound contaminant is rapidly degraded; however, a residual concentration may remain, which slowly degrades. Degradation of polycyclic aromatic hydrocarbons (PAHs) and mineral oil can be described

Isolation and application of hydrocarbon degradation of indigenous microbial from oil contaminated soil

International Nuclear Information System (INIS)

Dadang Sudrajat; Nana Mulyana; Tri Retno DL

2015-01-01

The aims of this research are to obtain indigenous potential microbes from bacterial and fungal groups which have capable of degrading hydrocarbon from crude oil contaminated soil. The research carried out were isolation, selection, and identification potential microbial isolates capable of degrading hydrocarbon from oil contaminated soil located at Cepu East Java. The isolates were tested for their growth and ability to degrades crude oil. Each isolate was inoculated unto minimum mineral salt medium (MSM) contained 1% crude oil. Viability and stability test of selected isolates were carried out on irradiated compost carrier materials contained 5% crude oil. The fours series microbial s consortium consists of microbial consortium I, II, III, and IV were tested for the in vitro biodegradability of hydrocarbon. The results shows there sixty two (62) isolates are obtained, among them 42 bacteria and 20 molds. From 42 bacterial isolates, only 8 strains were potent hydrocarbon degraders. Three of these isolates are identified Bacillus cereus (BMC2), Bacillus sp (BMC4), and Pseudomonas sp (BMC6). Whereas from 20 fungal isolates, only 4 strains were potent hydrocarbon degraders. Two of these isolates are identified Aspergillus fumigatus (FMC2) and Aspergillus niger (FMC6). All isolates show good growth in mineral salt medium contained crude oil with decrease in pH. The ability of decrease of TPH content by the bacterial and fungal isolates were 54, 61, 67, 74, and 78% respectively at day 30. The viability and stability of microbial isolates show considerable good viability on irradiated compost carrier materials after 14 days storage. From the fours series microbial consortium, the highest TPH degradation rates is found in microbial consortium III (BMC6, BMC2, and FMC6) with 89,1% in 5 weeks. (author)

Changes in hydrocarbon groups, soil ecotoxicity and microbiology along horizontal and vertical contamination gradients in an old landfarming field for oil refinery waste

International Nuclear Information System (INIS)

Mikkonen, Anu; Hakala, Kati P.; Lappi, Kaisa; Kondo, Elina; Vaalama, Anu; Suominen, Leena

2012-01-01

Horizontal and vertical contaminant gradients in an old landfarming field for oil refinery waste were characterised with the aim to assess parallel changes in hydrocarbon groups and general, microbiological and ecotoxicological soil characteristics. In the surface soil polar compounds were the most prevalent fraction of heptane-extractable hydrocarbons, superseding GC–FID-resolvable and high-molar-mass aliphatics and aromatics, but there was no indication of their relatively higher mobility or toxicity. The size of the polar fraction correlated poorly with soil physical, chemical and microbiological properties, which were better explained by the total heptane-extractable and total petroleum hydrocarbons (TPH). Deleterious effects on soil microbiology in situ were observed at surprisingly low TPH concentrations (0.3%). Due to the accumulation of polar and complexed degradation products, TPH seems an insufficient measure to assess the quality and monitor the remediation of soil with weathered hydrocarbon contamination. - Highlights: ► Weathered hydrocarbon contamination and soil quality on landfarm site were studied. ► Silica fractionation of hydrocarbons separated aliphatics, aromatics and polars. ► Polar hydrocarbon metabolites had accumulated in the surface soil. ► Total hydrocarbons and TPH correlated with soil quality changes better than polars. ► Toxic response of soil microbial biomass and activity were seen at low TPH (<0.5%). - Polar metabolites constitute the largest fraction of crude oil-derived contaminants in a landfarming site, but TPH better explains soil microbial and ecotoxicological responses.

Application of Chlorine-Assisted Chemical Vapor Deposition of Diamond at Low Temperatures

Science.gov (United States)

Pan, Chenyu; Altemir, David A.; Margrave, John L.; Hauge, Robert H.

1994-01-01

Low temperature deposition of diamond has been achieved by a chlorine-assisted diamond chemical vapor deposition (CA-CVD) process. This method begins with the thermal dissociation of molecular chlorine into atomic chlorine in a resistively heated graphite furnace at temperatures between 1300 and 1500 deg. C. The atomic chlorine, upon mixing, subsequently reacts with molecular hydrogen and hydrocarbons. The rapid exchange reactions between the atomic chlorine, molecular hydrogen, and hydrocarbons give rise to the atomic hydrogen and carbon precursors required for diamond deposition. Homoepitaxial diamond growth on diamond substrates has been studied over the substrate temperature range of 100-950 C. It was found that the diamond growth rates are approximately 0.2 microns/hr in the temperature range between 102 and 300 C and that the growth rates do not decrease significantly with a decrease in substrate temperature. This is unique because the traditional diamond deposition using H2/CH4 systems usually disappears at substrate temperatures below approx. 500 deg. C. This opens up a possible route to the deposition of diamond on low-melting point materials such as aluminum and its alloys.

Ecotoxicological and analytical assessment of hydrocarbon-contaminated soils and application to ecological risk assessment

Energy Technology Data Exchange (ETDEWEB)

Saterbak, A.; Toy, R.J.; Wong, D.C.L.; McMain, B.J.; Williams, M.P.; Dorn, P.B.; Brzuzy, L.P.; Chai, E.Y.; Salanitro, J.P.

1999-07-01

Ecotoxicological assessments of contaminated soil aim to understand the effect of introduced chemicals on the soil flora and fauna. Ecotoxicity test methods were developed and conducted on hydrocarbon-contaminated soils and on adjacent uncontaminated control soils from eight field locations. Tests included 7-d, 14-d, and chronic survival tests and reproduction assays for the earthworm (Eisenia fetida) and seed germination, root length, and plant growth assays for corn, lettuce, mustard, and wheat. Species-specific responses were observed with no-observed effect concentrations (NOECs) ranging from <1 to 100% contaminated soil. The 14-d earthworm survival NOEC was equal to or greater than the reproduction NOEC values for numbers of cocoons and juveniles, which were similar to one another. Cocoon and juvenile production varied among the control soils. Germination and root length NOECs for mustard and lettuce were less than NOECs for corn and wheat. Root length NOECs were similar to or less than seed germination NOECs. Statistically significant correlations for earthworm survival and seed germination as a function of hydrocarbon measurements were found. The 14-d earthworm survival and the seed germination tests are recommended for use in the context of a risk-based framework for the ecological assessment of contaminated sites.

Comparison of Laboratory Experiments of Chemical, Biological, and Thermal Methods for Treatment of Chlorinated Solvent DNAPL at Kærgård Plantage in Denmark

DEFF Research Database (Denmark)

Christophersen, Mette; Christensen, Jørgen Fjeldsø; Jørgensen, Torben H.

2010-01-01

The Kærgård Plantage megasite on the western coast of Denmark represents one of the most difficult remediation challenges in Scandinavia. Disposal of an estimated 280,000 m3 of pharmaceutical wastes at the site from 1956 to 1973 resulted in the development of a complex mixture of contaminants...... in soil and groundwater, including sulfonamides, barbiturates, aniline, pyridine, chlorinated solvents (chloroethenes), fuel hydrocarbons, mercury, cyanide, lithium and many other compounds.  Wastes were disposed in six pits that continue to leach contaminants to groundwater. Contaminants in groundwater...... technologies for remediation of the residual wastes below the water table - first in the laboratory and then in pilot tests. Given the complex and highly concentrated mixture of contaminants, implementation of multiple or sequenced remediation technologies may be required to achieve cleanup goals.  An...

Contaminated soil phytoremediation by Cyperus laxus Lam. cytochrome p450 EROD-activity induced by hydrocarbons in roots.

Science.gov (United States)

López-Martínez, S; Gallegos-Martínez, M E; Pérez-Flores, L J; Gutiérrez-Rojas, M

2008-01-01

Laboratory and greenhouse experiments with Cyperus laxus Lam were conducted to determine the rate and extent of phytoremediation and the effect of hydrocarbons on the cytochrome P450 EROD (7-ethoxyresorufin-O-deethylase) enzymatic activity in roots. Plants were cultivated on hydrocarbon-contaminated soil (HCS) and spiked perlite. Phytoremediation was evaluated using 6.5 kg HCS (173 +/- 15 mg total petroleum hydrocarbons [TPH] g(-1) of dry soil) pots at different moisture contents; the average removal rate was 3.46-0.25 mg TPH g(-1) dry soil month(-1) and 48% was removed when moisture was kept at 60%. The aromatic hydrocarbon fraction was the mostly removed, 60%; aliphatic, 51%; and polar 24% after 24-month experiments. In unplanted pots, TPH concentration did not exhibit significant differences with respect to the initial concentration. We confirmed that the presence of hydrocarbons induced ERODactivity up to 6.5-fold. Moreover, short-term experiments (up to 13 d) with spiked perlite demonstrated that two EROD activities in roots contributed to the total detected; 60% was found in the cytosolic and 40% in the microsomal fraction. To our knowledge, this is the first work that tries to build links between the hydrocarbon-inducible character of ERODactivity in roots and the phytoremediation ability of C. laxus in highly contaminated soils.

Characterization and Monitoring of Natural Attenuation of Chlorinated Solvents in Ground Water: A Systems Approach

Science.gov (United States)

Cutshall, N. H.; Gilmore, T.; Looney, B. B.; Vangelas, K. M.; Adams, K. M.; Sink, C. H.

2006-05-01

Like many US industries and businesses, the Department of Energy (DOE) is responsible for remediation and restoration of soils and ground water contaminated with chlorinated ethenes. Monitored Natural Attenuation (MNA) is an attractive remediation approach and is probably the universal end-stage technology for removing such contamination. Since 2003 we have carried out a multifaceted program at the Savannah River Site designed to advance the state of the art for MNA of chlorinated ethenes in soils and groundwater. Three lines of effort were originally planned: 1) Improving the fundamental science for MNA, 2) Promoting better characterization and monitoring (CM) techniques, and 3) Advancing the regulatory aspects of MNA management. A fourth line, developing enhanced attenuation methods based on sustainable natural processes, was added in order to deal with sites where the initial natural attenuation capacity cannot offset contaminant loading rates. These four lines have been pursued in an integrated and mutually supportive fashion. Many DOE site-cleanup program managers view CM as major expenses, especially for natural attenuation where measuring attenuation is complex and the most critical attenuation mechanisms cannot be determined directly. We have reviewed new and developing approaches to CM for potential application in support of natural attenuation of chlorinated hydrocarbons in ground water at DOE sites (Gilmore, Tyler, et al., 2006 WSRC-TR- 2005-00199). Although our project is focused on chlorinated ethenes, many of the concepts and strategies are also applicable to a wider range of contaminants including radionuclides and metals. The greatest savings in CM are likely to come from new management approaches. New approaches can be based, for example, on conceptual models of attenuation capacity, the ability of a formation to reduce risks caused by contaminants. Using the mass balance concept as a guide, the integrated mass flux of contaminant is compared to

A combined approach of physicochemical and biological methods for the characterization of petroleum hydrocarbon-contaminated soil.

Science.gov (United States)

Masakorala, Kanaji; Yao, Jun; Chandankere, Radhika; Liu, Haijun; Liu, Wenjuan; Cai, Minmin; Choi, Martin M F

2014-01-01

Main physicochemical and microbiological parameters of collected petroleum-contaminated soils with different degrees of contamination from DaGang oil field (southeast of Tianjin, northeast China) were comparatively analyzed in order to assess the influence of petroleum contaminants on the physicochemical and microbiological properties of soil. An integration of microcalorimetric technique with urease enzyme analysis was used with the aim to assess a general status of soil metabolism and the potential availability of nitrogen nutrient in soils stressed by petroleum-derived contaminants. The total petroleum hydrocarbon (TPH) content of contaminated soils varied from 752.3 to 29,114 mg kg(−1). Although the studied physicochemical and biological parameters showed variations dependent on TPH content, the correlation matrix showed also highly significant correlation coefficients among parameters, suggesting their utility in describing a complex matrix such as soil even in the presence of a high level of contaminants. The microcalorimetric measures gave evidence of microbial adaptation under highest TPH concentration; this would help in assessing the potential of a polluted soil to promote self-degradation of oil-derived hydrocarbon under natural or assisted remediation. The results highlighted the importance of the application of combined approach in the study of those parameters driving the soil amelioration and bioremediation.

Abundance and diversity of n-alkane-degrading bacteria in a forest soil co-contaminated with hydrocarbons and metals: a molecular study on alkB homologous genes.

Science.gov (United States)

Pérez-de-Mora, Alfredo; Engel, Marion; Schloter, Michael

2011-11-01

Unraveling functional genes related to biodegradation of organic compounds has profoundly improved our understanding of biological remediation processes, yet the ecology of such genes is only poorly understood. We used a culture-independent approach to assess the abundance and diversity of bacteria catalyzing the degradation of n-alkanes with a chain length between C(5) and C(16) at a forest site co-contaminated with mineral oil hydrocarbons and metals for nearly 60 years. The alkB gene coding for a rubredoxin-dependent alkane monooxygenase enzyme involved in the initial activation step of aerobic aliphatic hydrocarbon metabolism was used as biomarker. Within the area of study, four different zones were evaluated: one highly contaminated, two intermediately contaminated, and a noncontaminated zone. Contaminant concentrations, hydrocarbon profiles, and soil microbial respiration and biomass were studied. Abundance of n-alkane-degrading bacteria was quantified via real-time PCR of alkB, whereas genetic diversity was examined using molecular fingerprints (T-RFLP) and clone libraries. Along the contamination plume, hydrocarbon profiles and increased respiration rates suggested on-going natural attenuation at the site. Gene copy numbers of alkB were similar in contaminated and control areas. However, T-RFLP-based fingerprints suggested lower diversity and evenness of the n-alkane-degrading bacterial community in the highly contaminated zone compared to the other areas; both diversity and evenness were negatively correlated with metal and hydrocarbon concentrations. Phylogenetic analysis of alkB denoted a shift of the hydrocarbon-degrading bacterial community from Gram-positive bacteria in the control zone (most similar to Mycobacterium and Nocardia types) to Gram-negative genotypes in the contaminated zones (Acinetobacter and alkB sequences with little similarity to those of known bacteria). Our results underscore a qualitative rather than a quantitative response of

Bioavailability enhanced rhizosphere remediation of petroleum hydrocarbon contaminated soil

International Nuclear Information System (INIS)

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

2005-01-01

contain were analyzed by gas chromatography method. Four bioassays were used to measure toxicity during bio-remediation of soil contaminated by petroleum hydrocarbons: Microtox(R) test, SOSchromotest, lettuce seed germination and sheep red blood cell (RBS) hemolysis assay. Rhizosphere remediation was found to be effective for removal of polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPHs) from soil with the use of alfalfa inoculated by the Pseudomonas stutzeri MEV-S1 strain (RU 2228952 patent) and oats inoculated by the Pseudomonas alcaligenes MEV strain (RU 2228953 patent) in vegetation and field experiments. The reduction of the TPH and PAH concentrations in soil was accompanied by the reduction of integral toxicity and genotoxicity, evaluated by bio-testing. It is conceivable, therefore, that a possible way to optimize petroleum hydrocarbons phyto-remediation is the use of selected plants and microbial inoculants with specific chemotactic affinities and bio-surfactant production. The proposed technology for soil bio-remediation with the use of integrated plant-microbial system is ecologically and toxicologically safe and economically attractive

Bioavailability enhanced rhizosphere remediation of petroleum hydrocarbon contaminated soil

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-01

contain were analyzed by gas chromatography method. Four bioassays were used to measure toxicity during bio-remediation of soil contaminated by petroleum hydrocarbons: Microtox(R) test, SOSchromotest, lettuce seed germination and sheep red blood cell (RBS) hemolysis assay. Rhizosphere remediation was found to be effective for removal of polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPHs) from soil with the use of alfalfa inoculated by the Pseudomonas stutzeri MEV-S1 strain (RU 2228952 patent) and oats inoculated by the Pseudomonas alcaligenes MEV strain (RU 2228953 patent) in vegetation and field experiments. The reduction of the TPH and PAH concentrations in soil was accompanied by the reduction of integral toxicity and genotoxicity, evaluated by bio-testing. It is conceivable, therefore, that a possible way to optimize petroleum hydrocarbons phyto-remediation is the use of selected plants and microbial inoculants with specific chemotactic affinities and bio-surfactant production. The proposed technology for soil bio-remediation with the use of integrated plant-microbial system is ecologically and toxicologically safe and economically attractive.

Contact angles at the water-air interface of hydrocarbon-contaminated soils and clay minerals

Science.gov (United States)

Sofinskaya, O. A.; Kosterin, A. V.; Kosterina, E. A.

2016-12-01

Contact angles at the water-air interface have been measured for triturated preparations of clays and soils in order to assess changes in their hydrophobic properties under the effect of oil hydrocarbons. Tasks have been to determine the dynamics of contact angle under soil wetting conditions and to reveal the effect of chemical removal of organic matter from soils on the hydrophilicity of preparations. The potentialities of static and dynamic drop tests for assessing the hydrophilic-hydrophobic properties of soils have been estimated. Clays (kaolinite, gumbrine, and argillite) have been investigated, as well as plow horizons of soils from the Republic of Tatarstan: heavy loamy leached chernozem, medium loamy dark gray forest soil, and light loamy soddy-calcareous soil. The soils have been contaminated with raw oil and kerosene at rates of 0.1-3 wt %. In the uncontaminated and contaminated chernozem, capillary water capacity has been maintained for 250 days. The contact angles have been found to depend on the degree of dispersion of powdered preparation, the main type of clay minerals in the soil, the presence and amount of oxidation-resistant soil organic matter, and the soil-water contact time. Characteristic parameters of mathematical models for drop behavior on triturated preparations have been calculated. Contamination with hydrocarbons has resulted in a reliable increase in the contact angles of soil preparations. The hydrophobization of soil surface in chernozem is more active than in soils poorer in organic matter. The complete restoration of the hydrophilic properties of soils after hydrocarbon contamination is due to the oxidation of easily oxidizable organic matter at the low content of humus, or to wetting during several months in the absence of the mazut fraction.

Bacterial diversity in the active stage of a bioremediation system for mineral oil hydrocarbon-contaminated soils.

Science.gov (United States)

Popp, Nicole; Schlömann, Michael; Mau, Margit

2006-11-01

Soils contaminated with mineral oil hydrocarbons are often cleaned in off-site bioremediation systems. In order to find out which bacteria are active during the degradation phase in such systems, the diversity of the active microflora in a degrading soil remediation system was investigated by small-subunit (SSU) rRNA analysis. Two sequential RNA extracts from one soil sample were generated by a procedure incorporating bead beating. Both extracts were analysed separately by generating individual SSU rDNA clone libraries from cDNA of the two extracts. The sequencing results showed moderate diversity. The two clone libraries were dominated by Gammaproteobacteria, especially Pseudomonas spp. Alphaproteobacteria and Betaproteobacteria were two other large groups in the clone libraries. Actinobacteria, Firmicutes, Bacteroidetes and Epsilonproteobacteria were detected in lower numbers. The obtained sequences were predominantly related to genera for which cultivated representatives have been described, but were often clustered together in the phylogenetic tree, and the sequences that were most similar were originally obtained from soils and not from pure cultures. Most of the dominant genera in the clone libraries, e.g. Pseudomonas, Acinetobacter, Sphingomonas, Acidovorax and Thiobacillus, had already been detected in (mineral oil hydrocarbon) contaminated environmental samples. The occurrence of the genera Zymomonas and Rhodoferax was novel in mineral oil hydrocarbon-contaminated soil.

Post monitoring of a cyclodextrin remeditated chlorinated solvent contaminated aquifer

Science.gov (United States)

Blanford, W. J.

2006-12-01

Hydroxypropyl-â-cyclodextrin (HPâCD) has been tested successfully in the laboratory and in the field for enhanced flushing of low-polarity contaminants from aquifers. The cyclodextrin molecule forms a toroidal structure, which has a hydrophobic cavity. Within this cavity, organic compounds of appropriate shape and size can form inclusion complexes, which is the basis for the use of cyclodextrin in groundwater remediation. The hydrophilic exterior of the molecule makes cyclodextrin highly water-soluble. The solubility of cyclodextrins can be further enhanced by adding functional groups, such as hydroxypropyl groups, to the cyclodextrin core. The aqueous solubility of HPâCD exceeds 950 g/L. These high solubilities are advantageous for field applications because they permit relatively high concentrations of the flushing agent. In order for cyclodextrin to become a feasible remediative alternative, it must be demonstrate a short term resistance to biodegradation during field application, but ultimately biodegrade so as not to pose a long term presence in the aquifer. The potential for degradation of cyclodextrin as well as changes in the chlorinated solvents and groundwater geochemistry were examined during the post monitoring of a field demonstration in a shallow aquifer at Little Creek Naval Amphibious Base in Virginia. It was found that a portion of the cyclodextrin remaining in the aquifer after the cessation of field activities biodegraded during the 425 days of post monitoring. This degradation also led to the degradation of the chlorinated solvents trichloroethylene and 1,1-trichloroethane through both biological and chemical processes. The aquifer remained anaerobic with average dissolved oxygen levels below 0.5 mg/L. Dissolved nitrate and sulfate concentrations within the cyclodextrin plume decreased due their being used as terminal electron acceptors during the degradation of the cyclodextrin. The concentrations of total iron at the field site showed no

Change of magnetic properties due to fluctuations of hydrocarbon contaminated groundwater in unconsolidated sediments

Czech Academy of Sciences Publication Activity Database

Rijal, M. L.; Appel, E.; Petrovský, Eduard; Blaha, U.

2010-01-01

Roč. 158, č. 5 (2010), s. 1756-1762 ISSN 0269-7491 Institutional research plan: CEZ:AV0Z30120515 Keywords : hydrocarbon contamination * groundwater table fluctuation * magnetic properties * environmental magnetism Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 3.395, year: 2010

Structural and dynamical properties of chlorinated hydrocarbons studied with resonant inelastic x-ray scattering

Science.gov (United States)

Bohinc, R.; Žitnik, M.; Bučar, K.; Kavčič, M.; Carniato, S.; Journel, L.; Guillemin, R.; Marchenko, T.; Kawerk, E.; Simon, M.; Cao, W.

2016-04-01

We present a theoretical and experimental study of resonant inelastic x-ray scattering on a large group of chlorinated hydrocarbons: CH3Cl, CH2Cl2, CHCl3, CCl4, CH3CH2Cl, ClCH2CH2Cl, CH3CHCl2, CH3CCl3, C2H2Cl2-iso, C2H2Cl2-cis, C2H2Cl2-trans, and C6H5Cl. Differences in structural and dynamical properties of the molecules generated by diverse chemical environments are observed in the measured Cl(Kα) spectral maps as well as in the Cl(K) total fluorescence yield spectra. The energy position, relative intensity, and the width of the Franck-Condon distribution of low-lying σ∗ and π∗ resonances are extracted by a fitting procedure taking into account the experimental broadening. The theoretical values obtained with the transition potential and Δ Kohn-Sham methods are in good agreement with the experimental parameters indicating subtle differences due to variations in the molecular structure.

Activated Persulfate Treatment of 1,4-Dioxane in the Presence of Chlorinated Solvent Co-contaminants

Science.gov (United States)

Boving, T. T.; Eberle, D. E. H.; Ball, R.

2014-12-01

1,4-dioxane is an emerging groundwater contaminant and a likely human carcinogen. Due to its history as a stabilizer in chlorinated solvents, 1,4-dioxane is often found as a co-contaminant at solvent releases sites such as landfills, solvent recycling facilities, vapor decreasing operations, and fire-training areas. Historically, 1,4-dioxane was not routinely analyzed for at solvent release sites. The lack of analyses and the limitations of the analyses that were performed (i.e. high reporting limits) means that the scale of 1,4-dioxane subsurface contamination is still emerging. With the number of known 1,4-dioxane sites increasing, the need for cost effective 1,4-dioxane remediation technologies is rising as well. Remediation strategies that are capable of treating both 1,4-dioxane as well as chlorinated co-contaminants are of particular importance, especially when treating mixed-waste source zones. In the present study, we examined the fate of 1,4-dioxane during the targeted remediation of aqueous phase volatile organic compounds (VOC) using an activated persulfate based ISCO method (OxyZone®). Bench scale laboratory experiments are used to evaluate the treatability of 1,4-dioxane both as a single compound and in the presence of trichloroethene (TCE) and 1,1,1-trichloroethane (1,1,1-TCA). Possible dependencies on oxidant concentration and reaction kinetics were studied. Preliminary results are promising and show that OxyZone® is persistent and long lived, with oxidation of 1,4-dioxane continuing more than 12 days after initial dosage, even at dilute oxidant concentrations. The oxidative destruction of 1,4-dioxane, TCE and 1,1,1-TCA in single compound batch systems followed pseudo first order reaction kinetics. The rate of oxidation for each contaminant increased linearly with increasing persulfate concentration over the range of oxidant concentrations tested. The rate of oxidative destruction, from most easily degraded to least was: TCE > 1,4-Dioxane > 1

Stimulation of biological N2-fixation to accelerate the microbial remediation of soil contaminated by petroleum hydrocarbons

International Nuclear Information System (INIS)

Tereshenko, N.N.; Lushnikov, S.V.

2005-01-01

All remediation projects are comprised at least in accelerating the processes of the self-cleaning and self-restoration of biocenose which is led to increasing the functional activity of hydrocarbon-oxidizing microflora (HOM). Some of experts are carefully relate to introducing the commercial cultures of active hydrocarbon-consuming microbes into soils. They are afraid of unpredictable behavior of the cultures in soils. That why the stimulation of metabolic activity of indigenous soil microflora seems to be most preferable. In fact, contamination of soil with low nitrogen capacity by oil spills leads to significant deficient of nitrogen for HOM. Nitrogen content limits the soil self-restoration. Inorganic nitrogen fertilizers are supplied to recover the balance. The study of the microbial destruction of petroleum-hydrocarbons in association with biochemical transformation of nitrogen was carried out in lab and field experiments during 2000-2004. Study showed the activity of HOM correlates with rate of microbial fixing atmospheric nitrogen. Activity of biological N 2 -fixation significantly depends on supplying fertilizers (dose, date and kind). General practice of remediation of hydrocarbon-contaminated soils applies high initial doses of nitrogen-fertilizers (0.5-1 t per ha). Such practice leads to inhibition of N 2 -fixation processes, decreasing rate of oil destruction and loosing nitrogen due to activation of microbial denitrification. In opposition to that, the fractioned and advanced supplying mineral nitrogen fertilizers with aluminosilicate is the cost-effective approach to remediation of hydrocarbon-contaminated soils. Field experiments showed that the approach allows to increase efficiency of treatment up to 70-75% and to decrease operational expenses 2-3 times at least. (authors)

Dendrochemistry of multiple releases of chlorinated solvents at a former industrial site

Science.gov (United States)

Balouet, Jean Christophe; Burken, Joel G.; Karg, Frank; Vroblesky, Don; Smith, Kevin T.; Grudd, Hakan; Rindby, Anders; Beaujard, Francois; Chalot, Michel

2012-01-01

Trees can take up and assimilate contaminants from the soil, subsurface, and groundwater. Contaminants in the transpiration stream can become bound or incorporated into the annual rings formed in trees of the temperate zones. The chemical analysis of precisely dated tree rings, called dendrochemistry, can be used to interpret past plant interactions with contaminants. This investigation demonstrates that dendrochemistry can be used to generate historical scenarios of past contamination of groundwater by chlorinated solvents at a site in Verl, Germany. Increment cores from trees at the Verl site were collected and analyzed by energy-dispersive X-ray fluorescence (EDXRF) line scanning. The EDXRF profiles showed four to six time periods where tree rings had anomalously high concentrations of chlorine (Cl) as an indicator of potential contamination by chlorinated solvents.

Persistent chlorinated hydrocarbons and mercury in birds caught off the west coast of Spitsbergen. [Larus hyperboreus, Fulmarus glacialis, Uria lomvia, Alle alle, Somateria mollissima

Energy Technology Data Exchange (ETDEWEB)

Norheim, G.; Kjos-Hanssen, B.

1984-01-01

The tissue concentrations of DDE, PCB, hexachlorobenzene (HCB) and mercury were determined in five species of migrating seabirds: glaucous gull Larus hyperboreus; fulmar Fulmarus glacialis; Bruennech's guillemot Uria lomvia; little auk Alle alle and eider Somateria mollissima. These birds nest on Svalbard and were shot in May 1980 off the west coast of Spitsbergen. The highest levels of DDE, PCB and HCB were found in glaucous gull, whilst low levels were found in Bruennich's guillemot, little auk and, expecially, eider. Fulmars were intermediate. Highly significant correlations were found between the concentrations of HCB, DDE and PCB. These results could indicate that the Gulf Stream is a common source of these substances. The highest mercury levels were found in the fulmar; glaucous gull and eider were intermediate, whilst the lowest mercury levels were found in Bruennich's guillemot and little auk. There was no connection between the nutritional condition and concentrations of the pollutants determined. However, there seems to be a close relationship between the levels of chlorinated hydrocarbons and the trophic level of the birds in the food chain. A comparison between the present results and analyses of Antartic seabirds indicates that the aquatic food chain in the Arctic is more loaded with persistent chlorinated hydrocarbons than in the Antarctic, whereas more mercury seems to be found in Antarctic birds.

Biological Chlorine Cycling in Arctic Peat Soils

Science.gov (United States)

Zlamal, J. E.; Raab, T. K.; Lipson, D.

2014-12-01

Soils of the Arctic tundra near Barrow, Alaska are waterlogged and anoxic throughout most of the profile due to underlying permafrost. Microbial communities in these soils are adapted for the dominant anaerobic conditions and are capable of a surprising diversity of metabolic pathways. Anaerobic respiration in this environment warrants further study, particularly in the realm of electron cycling involving chlorine, which preliminary data suggest may play an important role in arctic anaerobic soil respiration. For decades, Cl was rarely studied outside of the context of solvent-contaminated sites due to the widely held belief that it is an inert element. However, Cl has increasingly become recognized as a metabolic player in microbial communities and soil cycling processes. Organic chlorinated compounds (Clorg) can be made by various organisms and used metabolically by others, such as serving as electron acceptors for microbes performing organohalide respiration. Sequencing our arctic soil samples has uncovered multiple genera of microorganisms capable of participating in many Cl-cycling processes including organohalide respiration, chlorinated hydrocarbon degradation, and perchlorate reduction. Metagenomic analysis of these soils has revealed genes for key enzymes of Cl-related metabolic processes such as dehalogenases and haloperoxidases, and close matches to genomes of known organohalide respiring microorganisms from the Dehalococcoides, Dechloromonas, Carboxydothermus, and Anaeromyxobacter genera. A TOX-100 Chlorine Analyzer was used to quantify total Cl in arctic soils, and these data were examined further to separate levels of inorganic Cl compounds and Clorg. Levels of Clorg increased with soil organic matter content, although total Cl levels lack this trend. X-ray Absorption Near Edge Structure (XANES) was used to provide information on the structure of Clorg in arctic soils, showing great diversity with Cl bound to both aromatic and alkyl groups

Chlorine signal attenuation in concrete.

Science.gov (United States)

Naqvi, A A; Maslehuddin, M; Ur-Rehman, Khateeb; Al-Amoudi, O S B

2015-11-01

The intensity of prompt gamma-ray was measured at various depths from chlorine-contaminated silica fume (SF) concrete slab concrete specimens using portable neutron generator-based prompt gamma-ray setup. The intensity of 6.11MeV chloride gamma-rays was measured from the chloride contaminated slab at distance of 15.25, 20.25, 25.25, 30.25 and 35.25cm from neutron target in a SF cement concrete slab specimens. Due to attenuation of thermal neutron flux and emitted gamma-ray intensity in SF cement concrete at various depths, the measured intensity of chlorine gamma-rays decreases non-linearly with increasing depth in concrete. A good agreement was noted between the experimental results and the results of Monte Carlo simulation. This study has provided useful experimental data for evaluating the chloride contamination in the SF concrete utilizing gamma-ray attenuation method. Copyright © 2015 Elsevier Ltd. All rights reserved.

Factors affecting hydrocarbon removal by air stripping

International Nuclear Information System (INIS)

McFarland, W.E.

1992-01-01

This paper includes an overview of the theory of air stripping design considerations and the factors affecting stripper performance. Effects of temperature, contaminant characteristics, stripping tower geometry and air/water ratios on removal performance are discussed. The discussion includes treatment of groundwater contaminated with petroleum hydrocarbons and chlorinated solvents such as TCE and PCE. Control of VOC emissions from air strippers has become a major concern in recent years, due to more stringent restrictions on air quality in many areas. This paper includes an overview of available technology to control air emissions (including activated carbon adsorption, catalytic oxidation and steam stripping) and the effects of air emission control on overall efficiency of the treatment process. The paper includes an overview of the relative performance of various packing materials for air strippers and explains the relative advantages and disadvantages of comparative packing materials. Field conditions affecting selection of packing materials are also discussed. Practical guidelines for the design of air stripping systems are presented, as well as actual case studies of full-scale air stripping projects

California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

International Nuclear Information System (INIS)

Del Toro, Ligeia; Heckel, Gisela; Camacho-Ibar, Victor F.; Schramm, Yolanda

2006-01-01

Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. ΣDDTs were the dominant group (geometric mean 3.8 μg/g lipid weight), followed by polychlorinated biphenyls (ΣPCBs, 2.96 μg/g), chlordanes (0.12 μg/g) and hexachlorocyclohexanes (0.06 μg/g). The ΣDDTs/ΣPCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA

California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

Energy Technology Data Exchange (ETDEWEB)

Del Toro, Ligeia [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico); Heckel, Gisela [Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico) and Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, B.C. Km 107 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860 (Mexico)]. E-mail: gheckel@cicese.mx; Camacho-Ibar, Victor F. [Instituto de Investigaciones Oceanologicas, UABC, Apdo. Postal 453, Ensenada, Baja California 22860 (Mexico); Schramm, Yolanda [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico)

2006-07-15

Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. {sigma}DDTs were the dominant group (geometric mean 3.8 {mu}g/g lipid weight), followed by polychlorinated biphenyls ({sigma}PCBs, 2.96 {mu}g/g), chlordanes (0.12 {mu}g/g) and hexachlorocyclohexanes (0.06 {mu}g/g). The {sigma}DDTs/{sigma}PCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA.

Effects of oxygen supply on the biodegradation rate in oil hydrocarbons contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Zawierucha, I [Institute of Chemistry and Environment Protection, Jan Dlugosz University of Czestochowa, Waszyngtona 4/8, 42-200 Czestochowa (Poland); Malina, G, E-mail: iwona_zawierucha@o2.pl [Faculty of Hydrogeology and Geology Engineering, Department of Geology, Geophysics and Environment Protection, AGH University of Science and Technology, Mickiewicza 30, 30-059 Cracow (Poland)

2011-04-01

Respirometry studies using the 10-chamber Micro-Oxymax respirometer (Columbus, Ohio) were conducted to determine the effect of biostimulation (by diverse ways of O{sub 2} supply) on enhancing biodegradation in soils contaminated with oil hydrocarbons. Soil was collected from a former military airport in Kluczewo, Poland. Oxygen was supplied by means of aerated water, aqueous solutions of H{sub 2}O{sub 2} and KMnO{sub 4}. The biodegradation was evaluated on the basis of O{sub 2} uptake and CO{sub 2} production. The O{sub 2} consumption and CO{sub 2} production rates during hydrocarbons biodegradation were estimated from the slopes of cumulative curve linear regressions. The pertinent intrinsic and enhanced biodegradation rates were calculated on the basis of mass balance equation and O{sub 2} uptake and CO{sub 2} production rates. The biodegradation rates of 5-7 times higher as compared to a control were observed when the aqueous solution of KMnO{sub 4} in concentration of 20 g L{sup -1} was applied. Permanganate is known to readily oxidize alkene carbon - carbon double bonds; so it can be successfully applied in remediation technology for soils contaminated with oil hydrocarbons. While hydrocarbons are not completely mineralized by permanganate oxidation reactions, their structure is altered by polar functional groups providing vast improvements in aqueous solubility and availability for biodegradation. The 3% aqueous solution of H{sub 2}O{sub 2} caused significant improvement of the biodegradation rates as compared to a control (on average about 260%). Aerobic biodegradation of hydrocarbons can benefit from the presence of oxygen released during H{sub 2}O{sub 2} decomposition. Adding of aerated water resulted in an increase of biodegradation rates (about 114 - 229%) as compared to a control. The aerated water can both be the source of oxygen for microorganisms and determine the transport of substrate to bacteria cells.

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

PILOT-SCALE SUBCRITICAL WATER REMEDIATION OF POLYCYCLIC AROMATIC HYDROCARBON- AND PESTICIDE-CONTAMINATED SOIL. (R825394)

Science.gov (United States)

Subcritical water (hot water under enough pressure to maintain the liquid state) was used to remove polycyclic aromatic hydrocarbons (PAHs) and pesticides from highly contaminated soils. Laboratory-scale (8 g of soil) experiments were used to determine conditions f...

Tools for Management of Chlorinated Solvent - Contaminated Sites

Science.gov (United States)

2009-12-03

Movie Lee Ann Doner – (2008) MS CSU “Sandy aquifers” Image from Fred Payne /ARCADIS New Paradigm After NRC 2005 l~r SERDP. Advancing solvent plume...Situ Bioremediation Using Emulsified  Edible  Oil”   AFCEE (http://www.afcee.brooks.af.mil/products/techtrans/) - “Principles and Practices of Enhanced...Anaerobic Bioremediation of  Chlorinated Solvents”  - “Protocol for In Situ Bioremediation of Chlorinated Solvents Using  Edible  Oil” 232 Short Course

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

International Nuclear Information System (INIS)

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

1991-01-01

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

Assessing the hydrocarbon degrading potential of indigenous bacteria isolated from crude oil tank bottom sludge and hydrocarbon-contaminated soil of Azzawiya oil refinery, Libya.

Science.gov (United States)

Mansur, Abdulatif A; Adetutu, Eric M; Kadali, Krishna K; Morrison, Paul D; Nurulita, Yuana; Ball, Andrew S

2014-09-01

The disposal of hazardous crude oil tank bottom sludge (COTBS) represents a significant waste management burden for South Mediterranean countries. Currently, the application of biological systems (bioremediation) for the treatment of COTBS is not widely practiced in these countries. Therefore, this study aims to develop the potential for bioremediation in this region through assessment of the abilities of indigenous hydrocarbonoclastic microorganisms from Libyan Hamada COTBS for the biotreatment of Libyan COTBS-contaminated environments. Bacteria were isolated from COTBS, COTBS-contaminated soil, treated COTBS-contaminated soil, and uncontaminated soil using Bushnell Hass medium amended with Hamada crude oil (1 %) as the main carbon source. Overall, 49 bacterial phenotypes were detected, and their individual abilities to degrade Hamada crude and selected COBTS fractions (naphthalene, phenanthrene, eicosane, octadecane and hexane) were evaluated using MT2 Biolog plates. Analyses using average well colour development showed that ~90 % of bacterial isolates were capable of utilizing representative aromatic fractions compared to 51 % utilization of representative aliphatics. Interestingly, more hydrocarbonoclastic isolates were obtained from treated contaminated soils (42.9 %) than from COTBS (26.5 %) or COTBS-contaminated (30.6 %) and control (0 %) soils. Hierarchical cluster analysis (HCA) separated the isolates into two clusters with microorganisms in cluster 2 being 1.7- to 5-fold better at hydrocarbon degradation than those in cluster 1. Cluster 2 isolates belonged to the putative hydrocarbon-degrading genera; Pseudomonas, Bacillus, Arthrobacter and Brevundimonas with 57 % of these isolates being obtained from treated COTBS-contaminated soil. Overall, this study demonstrates that the potential for PAH degradation exists for the bioremediation of Hamada COTBS-contaminated environments in Libya. This represents the first report on the isolation of

Metagenome-based metabolic reconstruction reveals the ecophysiological function of Epsilonproteobacteria in a hydrocarbon-contaminated sulfidic aquifer

Directory of Open Access Journals (Sweden)

Andreas Hardy Keller

2015-12-01

Full Text Available The population genome of an uncultured bacterium assigned to the Campylobacterales (Epsilonproteobacteria was reconstructed from a metagenome dataset obtained by whole-genome shotgun pyrosequencing. Genomic DNA was extracted from a sulfate-reducing, m-xylene-mineralizing enrichment culture isolated from groundwater of a benzene-contaminated sulfidic aquifer. The identical epsilonproteobacterial phylotype has previously been detected in toluene- or benzene-mineralizing, sulfate-reducing consortia enriched from the same site. Previous stable isotope probing experiments with 13C6-labeled benzene suggested that this phylotype assimilates benzene-derived carbon in a syntrophic benzene-mineralizing consortium that uses sulfate as terminal electron acceptor. However, the type of energy metabolism and the ecophysiological function of this epsilonproteobacterium within aromatic hydrocarbon-degrading consortia and in the sulfidic aquifer are poorly understood.Annotation of the epsilonproteobacterial population genome suggests that the bacterium plays a key role in sulfur cycling as indicated by the presence of a sqr gene encoding a sulfide quinone oxidoreductase and psr genes encoding a polysulfide reductase. It may gain energy by using sulfide or hydrogen/formate as electron donors. Polysulfide, fumarate, as well as oxygen are potential electron acceptors. Auto- or mixotrophic carbon metabolism seems plausible since a complete reductive citric acid cycle was detected. Thus the bacterium can thrive in pristine groundwater as well as in hydrocarbon-contaminated aquifers. In hydrocarbon-contaminated sulfidic habitats, the epsilonproteobacterium may generate energy by coupling the oxidation of hydrogen or formate and highly abundant sulfide with the reduction of fumarate and/or polysulfide, accompanied by efficient assimilation of acetate produced during fermentation or incomplete oxidation of hydrocarbons. The highly efficient assimilation of acetate was

Metagenome-Based Metabolic Reconstruction Reveals the Ecophysiological Function of Epsilonproteobacteria in a Hydrocarbon-Contaminated Sulfidic Aquifer.

Science.gov (United States)

Keller, Andreas H; Schleinitz, Kathleen M; Starke, Robert; Bertilsson, Stefan; Vogt, Carsten; Kleinsteuber, Sabine

2015-01-01

The population genome of an uncultured bacterium assigned to the Campylobacterales (Epsilonproteobacteria) was reconstructed from a metagenome dataset obtained by whole-genome shotgun pyrosequencing. Genomic DNA was extracted from a sulfate-reducing, m-xylene-mineralizing enrichment culture isolated from groundwater of a benzene-contaminated sulfidic aquifer. The identical epsilonproteobacterial phylotype has previously been detected in toluene- or benzene-mineralizing, sulfate-reducing consortia enriched from the same site. Previous stable isotope probing (SIP) experiments with (13)C6-labeled benzene suggested that this phylotype assimilates benzene-derived carbon in a syntrophic benzene-mineralizing consortium that uses sulfate as terminal electron acceptor. However, the type of energy metabolism and the ecophysiological function of this epsilonproteobacterium within aromatic hydrocarbon-degrading consortia and in the sulfidic aquifer are poorly understood. Annotation of the epsilonproteobacterial population genome suggests that the bacterium plays a key role in sulfur cycling as indicated by the presence of an sqr gene encoding a sulfide quinone oxidoreductase and psr genes encoding a polysulfide reductase. It may gain energy by using sulfide or hydrogen/formate as electron donors. Polysulfide, fumarate, as well as oxygen are potential electron acceptors. Auto- or mixotrophic carbon metabolism seems plausible since a complete reductive citric acid cycle was detected. Thus the bacterium can thrive in pristine groundwater as well as in hydrocarbon-contaminated aquifers. In hydrocarbon-contaminated sulfidic habitats, the epsilonproteobacterium may generate energy by coupling the oxidation of hydrogen or formate and highly abundant sulfide with the reduction of fumarate and/or polysulfide, accompanied by efficient assimilation of acetate produced during fermentation or incomplete oxidation of hydrocarbons. The highly efficient assimilation of acetate was recently

Development and successful field tests of a multi-process phytoremediation system for decontamination of persistent petroleum and organic contaminants in soil

Energy Technology Data Exchange (ETDEWEB)

Greenberg, B.M.; Huang, X.-D.; Gurska, Y.; Gerhardt, K.E.; Lampi, M.A.; Khalid, A.; Isherwood, D.; Chang, P.; Wang, W.; Wang, H.; Dixon, D.G.; Glick, B.R. [Waterloo Univ., ON (Canada). Dept. of Biology

2006-07-01

If efficient systems with rapid remediation kinetics can be realized, phytoremediation of persistent contaminants from soils holds great promise. A multi-process phytoremediation system (MPPS) with accelerated remediation kinetics that effectively removes polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPHs) and chlorinated hydrocarbons (CHCs) from soils has been developed. A plant growth promoting rhizobacteria interaction is the main element for success as it mitigates stress ethylene effects in plants, leading to high root biomass which, in turn, promotes growth of rhizosphere organisms. Based on the success of greenhouse experiments, field tests of the MPPS were initiated at an Imperial Oil land farm site in Sarnia, Ontario in the summer of 2004, followed by 127 field tests at the same site in the summer of 2005 and 2006. In addition, a total petroleum hydrocarbons (TPH) contaminated site in Alberta was used in 2005 and 2006. The study presented and discussed selected results of successful greenhouse, pilot field tests and field tests of the MPPS. It was concluded that increased root biomass is achieved in the contaminated soils, which leads to more efficient and complete removal of TPHs in the field. Three years of field trials of the MPPS showed that remediation continues with successive seasons. 27 refs., 2 tabs., 1 fig.

Reversed phase liquid chromatography with UV absorbance and flame ionization detection using a water mobile phase and a cyano propyl stationary phase Analysis of alcohols and chlorinated hydrocarbons.

Science.gov (United States)

Quigley, W W; Ecker, S T; Vahey, P G; Synovec, R E

1999-10-01

The development of liquid chromatography with a commercially available cyano propyl stationary phase and a 100% water mobile phase is reported. Separations were performed at ambient temperature, simplifying instrumental requirements. Excellent separation efficiency using a water mobile phase was achieved, for example N=18 800, or 75 200 m(-1), was obtained for resorcinol, at a retention factor of k'=4.88 (retention time of 9.55 min at 1 ml min(-1) for a 25 cmx4.6 mm i.d. column, packed with 5 mum diameter particles with the cyano propyl stationary phase). A separation via reversed phase liquid chromatography (RP-LC) with a 100% water mobile phase of six phenols and related compounds was compared to a separation of the same compounds by traditional RP-LC, using octadecylsilane (ODS), i.e. C18, bound to silica and an aqueous mobile phase modified with acetonitrile. Nearly identical analysis time was achieved for the separation of six phenols and related compounds using the cyano propyl stationary phase with a 100% water mobile phase, as compared to traditional RP-LC requiring a relatively large fraction of organic solvent modifier in the mobile phase (25% acetonitrile:75% water). Additional understanding of the retention mechanism with the 100% water mobile phase was obtained by relating measured retention factors of aliphatic alcohols, phenols and related compounds, and chlorinated hydrocarbons to their octanol:water partition coefficients. The retention mechanism is found to be consistent with a RP-LC mechanism coupled with an additional retention effect due to residual hydroxyl groups on the cyano propyl stationary phase. Advantages due to a 100% water mobile phase for the chemical analysis of alcohol mixtures and chlorinated hydrocarbons are reported. By placing an absorbance detector in-series and preceding a novel drop interface to a flame ionization detector (FID), selective detection of a separated mixture of phenols and related compounds and aliphatic

New model of chlorine-wall reaction for simulating chlorine concentration in drinking water distribution systems.

Science.gov (United States)

Fisher, Ian; Kastl, George; Sathasivan, Arumugam

2017-11-15

Accurate modelling of chlorine concentrations throughout a drinking water system needs sound mathematical descriptions of decay mechanisms in bulk water and at pipe walls. Wall-reaction rates along pipelines in three different systems were calculated from differences between field chlorine profiles and accurately modelled bulk decay. Lined pipes with sufficiently large diameters (>500 mm) and higher chlorine concentrations (>0.5 mg/L) had negligible wall-decay rates, compared with bulk-decay rates. Further downstream, wall-reaction rate consistently increased (peaking around 0.15 mg/dm 2 /h) as chlorine concentration decreased, until mass-transport to the wall was controlling wall reaction. These results contradict wall-reaction models, including those incorporated in the EPANET software, which assume wall decay is of either zero-order (constant decay rate) or first-order (wall-decay rate reduces with chlorine concentration). Instead, results are consistent with facilitation of the wall reaction by biofilm activity, rather than surficial chemical reactions. A new model of wall reaction combines the effect of biofilm activity moderated by chlorine concentration and mass-transport limitation. This wall reaction model, with an accurate bulk chlorine decay model, is essential for sufficiently accurate prediction of chlorine residuals towards the end of distribution systems and therefore control of microbial contamination. Implementing this model in EPANET-MSX (or similar) software enables the accurate chlorine modelling required for improving disinfection strategies in drinking water networks. New insight into the effect of chlorine on biofilm can also assist in controlling biofilm to maintain chlorine residuals. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

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

Science.gov (United States)

Falciglia, P P; Vagliasindi, F G A

2014-01-01

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

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

Biodegradation of petroleum hydrocarbons at low temperatures

International Nuclear Information System (INIS)

Whyte, L. G.; Greer, C W.

1999-01-01

Bioremediation of contaminated Arctic sites has been proposed as the logistically and economically most favorable solution despite the known technical difficulties. The difficulties involve the inhibition of pollutants removal by biodegradation below freezing temperatures and the relative slowness of the process to remove enough hydrocarbon pollutants during the above-freezing summer months. Despite these formidable drawbacks, biodegradation of hydrocarbon contaminants is possible even in below-zero temperatures, especially if indigenous psychrophilic and psychrotropic micro-organism are used. This paper reports results of a study involving several hydrocarbon-degrading psychrotropic bacteria and suggests bioaugmentation with specific cold-adapted organisms and/or biostimulation with commercial fertilizers for enhancing degradation of specific contaminants in soils from northern Canada. An evaluation of the biodegradation potential of hydrocarbon contaminated soils in the high Arctic suggested that the contaminated soils contained sufficient numbers of cold-adapted hydrocarbon-degrading bacteria and that the addition of fertilizer was sufficient to enhance the level of hydrocarbon degradation at low ambient summer temperatures. 9 refs., 2 tabs., 3 figs

Successful implementation of controlled aerobic bioremediation technology at hydrocarbon contaminated sites in the state of Delaware

International Nuclear Information System (INIS)

Harmon, C.D.; Hiller, A.V.; Carberry, J.B.

1994-01-01

WIK Associates, Inc. of New Castle, Delaware, has been working over the last two years to improve and advance a cost effective method of treating hydrocarbon contaminated soils. The first section of this paper describes treatment methods and associated benefits such as increased control over environmental parameters. The second part of this paper describes work performed in attempting to predict degradation rates for varying types of hydrocarbon contamination under varying conditions. This research is based on data gathered in performing on-site bioremediation as described. A third section included in this paper describes the unique perspective of a State regulator responsible for overseeing remediation efforts evolving from leaking underground storage tanks. This section describes regulatory issues and procedures in Delaware and how the Department handles the submission and implementation of corrective action work plans, through project closure with thorough documentation of the remediation

Procedure manual: protocol for regulation of petroleum hydrocarbons in water under the special waste and contaminated sites regulation

International Nuclear Information System (INIS)

Evans, P.; Partridge, E.

2002-05-01

This document details the regulation governing numerical standards for petroleum hydrocarbons in water under the special waste and contaminated sites regulations of British Columbia. Groundwater containing benzene, toluene, ethylbenzene or xylenes in excess of the leachate standards is exempted from the regulatory regime of the Special Waste Regulation. The document contains a description of the conditions that apply to the management of petroleum hydrocarbons in water at contaminated sites. Some definitions are included, followed by an overview of the regulation. The third section deals with authorization and mandatory conditions, while additional requirements that might apply are enumerated in section four. This protocol directly affects the Environmental Management, and the Environmental Protection Regional Operations organizations. 1 tab

Potential impact of soil microbial heterogeneity on the persistence of hydrocarbons in contaminated subsurface soils.

Science.gov (United States)

Aleer, Sam; Adetutu, Eric M; Weber, John; Ball, Andrew S; Juhasz, Albert L

2014-04-01

In situ bioremediation is potentially a cost effective treatment strategy for subsurface soils contaminated with petroleum hydrocarbons, however, limited information is available regarding the impact of soil spatial heterogeneity on bioremediation efficacy. In this study, we assessed issues associated with hydrocarbon biodegradation and soil spatial heterogeneity (samples designated as FTF 1, 5 and 8) from a site in which in situ bioremediation was proposed for hydrocarbon removal. Test pit activities showed similarities in FTF soil profiles with elevated hydrocarbon concentrations detected in all soils at 2 m below ground surface. However, PCR-DGGE-based cluster analysis showed that the bacterial community in FTF 5 (at 2 m) was substantially different (53% dissimilar) and 2-3 fold more diverse than communities in FTF 1 and 8 (with 80% similarity). When hydrocarbon degrading potential was assessed, differences were observed in the extent of (14)C-benzene mineralisation under aerobic conditions with FTF 5 exhibiting the highest hydrocarbon removal potential compared to FTF 1 and 8. Further analysis indicated that the FTF 5 microbial community was substantially different from other FTF samples and dominated by putative hydrocarbon degraders belonging to Pseudomonads, Xanthomonads and Enterobacteria. However, hydrocarbon removal in FTF 5 under anaerobic conditions with nitrate and sulphate electron acceptors was limited suggesting that aerobic conditions were crucial for hydrocarbon removal. This study highlights the importance of assessing available microbial capacity prior to bioremediation and shows that the site's spatial heterogeneity can adversely affect the success of in situ bioremediation unless area-specific optimizations are performed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Process for the restoration of solids contaminated with hydrocarbons and heavy organic compounds

International Nuclear Information System (INIS)

Bala, G.A.; Thomas, C.P.; Jackson, J.D.; McMillin, R.A.

1994-01-01

Processes have been developed for the restoration of environments contaminated with hydrocarbons and heavy organics. The intended product is a field deployable materials handling system and phase separation process ranging in size from 1 yd 3 /hr to 50 yd 3 /hr for commercial application to environmental problems associated with the exploration, production, refining and transport of petroleum, petroleum products and organic chemicals. Effluents from contaminated sites will be clean solids (classified by size if appropriate), and the concentrated contaminant. The technology is based on biochemical solvation, liquid/liquid and liquid/solid extractions, materials classification, mechanical and hydraulic scrubbing, and phase separation of organic and aqueous phases. Fluid use is minimized through utilization of closed-loop (recycle) systems. Contaminants that are removed from the solid materials may be destroyed, disposed of using existing technologies, or used on-site for cogeneration of /power for plant operations. Additionally, if the contaminant is a valued product, the material may be recovered for application or sale. Clean solid material is not sterilized and may be returned to normal agricultural, commercial, residential or recreational use in most instances

Effect in laboratory of addition of inorganic fertilizers made in degradation of hydrocarbon on contaminated soil by oil

International Nuclear Information System (INIS)

Pardo Castro, Jenny Liliana; Perdomo Rojas, Maria Carolina; Benavides Lopez de Mesa, Joaquin L

2004-01-01

At present one of the most important environmental problems is contamination of soil ecosystem by hydrocarbon spilling mainly of oil and its derivates, which occurs when oil is explored or transported. Furthermore in Colombia it occurs due to violent assaults made by men outside of law against petroleum infrastructure. To solve this problem there are treatment methods to recover contaminated soil as Land farming technique, adding organic nutrients. In this research this technique was evaluated in vitro, through a design of six experimental units (EU) which contained contaminated soil with crude oil; three EU were treated with Triple 15 inorganic fertilizer and the other three were taken as biotic control. Land farming effectiveness was determined by pH analysis, humidity percent, temperature, count of total heterotrophic microorganisms, and probable number of I degrades microorganisms, nutrients and total hydrocarbons for a four month experimental period At the d of that period, in Land farming treatment with nutrients added was achieved a high remotion percentage TPH up to 91 %, getting final TPH concentration of 2028 ppm comparing biotic control in which the remotion percentage achieved up to 65% and a TPH final concentration was 8049 ppm thus, it could demonstrate that nutrient addition optimizes the degrading hydrocarbon process in soil

Successful field tests of a multi-process phytoremediation system for decontamination of persistent petroleum and organic contaminants

Energy Technology Data Exchange (ETDEWEB)

Greenberg, B.M.; Huang, X.D.; Gurska, Y.; Gerhardt, K.E.; Wang, W.; Lampi, M.A.; Zhang, C.; Khalid, A.; Isherwood, D.; Chang, P.; Wang, H.; Dixon, D.G.; Glick, B.R. [Waterloo Univ., ON (Canada)

2006-07-01

A large number of aquatic and terrestrial environments are polluted with various levels of toxicants. Metals, organics and total petroleum hydrocarbons from anthropogenic sources pose a risk to both human health and the health of ecosystems. Although these persistent contaminants are difficult to remediate, several industrial sites throughout North America are being remediated as part of land reclamation and restoration programs. This paper addressed the issue of phytoremediation for removing contaminants from soils. Phytoremediation is considered to be a viable remediation strategy because the increased biomass of plants, relative to the biomass of soil microbes in the absence of plants, allows for higher throughput. Extensive root systems can infiltrate large volumes of soil, thus promoting degradation of contaminants over a wide area. This paper described a newly developed multi-process phytoremediation system with accelerated remediation kinetics to effectively remove polycyclic aromatic hydrocarbons (PAH), total petroleum hydrocarbons (TPH) and chlorinated hydrocarbons (CHC) from soils. The system combines land farming/sunlight exposure; inoculation of contaminant degrading bacteria; and, plant growth with plant growth promoting rhizobacteria which mitigates the effects of stress ethylene in plants. The primary factor for success was the interaction between the plant and the plant growth promoting rhizobacteria. Several field tests were conducted following successful greenhouse tests. Results at a TPH contaminated site in Sarnia, Ontario showed that over a 2 year period, 60 to 70 per cent remediation of 15 per cent TPH was achieved. At a site in Turner Valley, Alberta, 35 per cent remediation of 1 per cent recalcitrant TPH was achieved, while a DDT contaminated site near Simcoe, Ontario had nearly 30 per cent of CHC removed in a 3 month period. 34 refs., 2 tabs., 2 figs.

Successful field tests of a multi-process phytoremediation system for decontamination of persistent petroleum and organic contaminants

International Nuclear Information System (INIS)

Greenberg, B.M.; Huang, X.D.; Gurska, Y.; Gerhardt, K.E.; Wang, W.; Lampi, M.A.; Zhang, C.; Khalid, A.; Isherwood, D.; Chang, P.; Wang, H.; Dixon, D.G.; Glick, B.R.

2006-01-01

A large number of aquatic and terrestrial environments are polluted with various levels of toxicants. Metals, organics and total petroleum hydrocarbons from anthropogenic sources pose a risk to both human health and the health of ecosystems. Although these persistent contaminants are difficult to remediate, several industrial sites throughout North America are being remediated as part of land reclamation and restoration programs. This paper addressed the issue of phytoremediation for removing contaminants from soils. Phytoremediation is considered to be a viable remediation strategy because the increased biomass of plants, relative to the biomass of soil microbes in the absence of plants, allows for higher throughput. Extensive root systems can infiltrate large volumes of soil, thus promoting degradation of contaminants over a wide area. This paper described a newly developed multi-process phytoremediation system with accelerated remediation kinetics to effectively remove polycyclic aromatic hydrocarbons (PAH), total petroleum hydrocarbons (TPH) and chlorinated hydrocarbons (CHC) from soils. The system combines land farming/sunlight exposure; inoculation of contaminant degrading bacteria; and, plant growth with plant growth promoting rhizobacteria which mitigates the effects of stress ethylene in plants. The primary factor for success was the interaction between the plant and the plant growth promoting rhizobacteria. Several field tests were conducted following successful greenhouse tests. Results at a TPH contaminated site in Sarnia, Ontario showed that over a 2 year period, 60 to 70 per cent remediation of 15 per cent TPH was achieved. At a site in Turner Valley, Alberta, 35 per cent remediation of 1 per cent recalcitrant TPH was achieved, while a DDT contaminated site near Simcoe, Ontario had nearly 30 per cent of CHC removed in a 3 month period. 34 refs., 2 tabs., 2 figs

Halogenated hydrocarbons - an environmental problem

Energy Technology Data Exchange (ETDEWEB)

Schoeler, H F; Thofern, E

1984-01-01

The paper provides a survey of the incidence of highly volatile halogenated hydrocarbons in ground, surface and drinking water as well as in the snows of Western Germany. Almost the entire production of chlorinated solvents is released into the environment. The absorption media are mostly soil, water and atmosphere. Whereas in the atmosphere elimination reactions take place, solvents that have passed the soil get into the ground water owing to their persistence and can cause considerable pollutions of drinking water. Moreover haloforms may occur in drinking water, which are produced during chlorine disinfection of pre-treated water.

Potential Use of Polyacrylamide Encapsulation for Treatment of Petroleum Drilling Cuttings and Hydrocarbon Contaminated Soil

Directory of Open Access Journals (Sweden)

Randy H. Adams

2011-07-01

Full Text Available Mineral soil of alluvial origin, contaminated with diesel+lubricating oil (1:2, was treated with a commercial polyacrylamide product at 100 % of the distributer recommended dosage, producing a reduction in hydrocarbon concentration (EPA 9074 of 76 % that remained stable during the study period (38 days and even after thermal treatment (60 ºC, 18 hrs.. Increasing the dosage to 150 % did not improve the treatment results, but repeating the treatment (at 100 % resulted in a slight additional reduction (4 %. Similar results were obtained with oil-based drilling cuttings (~60 % reduction at both 100 % and 150 %. Pre-drying of the drilling cuttings prior to treatment did not improve the hydrocarbon reduction, but it did produce smaller, potentially more stable aggregates (0.5 – 1-0 mm in diameter. The treatment of organic soil resulted in a similar reduction in hydrocarbon concentration (65 % and a reduction of acute toxicity (Microtox to below background levels, however this effect was not stable. An additional application (including mixing of the polyacrylamide product resulted in partial disintegration of the organic fibres and release of the stabilized hydrocarbons, measuring an overall increase in hydrocarbon concentration of 19 %.

[Compositions and residual properties of petroleum hydrocarbon in contaminated soil of the oilfields].

Science.gov (United States)

Hu, Di; Li, Chuan; Dong, Qian-Qian; Li, Li-Ming; Li, Guang-He

2014-01-01

The aims of this study were to determine the compositions and residual properties of petroleum hydrocarbon in soil, as well as to identify the source and weathering degree of the pollution. A total of 5 producing wells in Gudao and Hekou oil producing region of Shengli oilfields were analyzed. More than 50 individual target compounds including straight-and branched-chain alkanes( n-alkanes, pristine and phytane) and polycyclic aromatic hydrocarbons (PAHs) in soil samples and crude oil were determined by gas chromatography-mass spectrometry (GC-MS). The percentages of chain alkanes and PAHs in total solvent extractable matters(TSEM) of soil samples were both much lower than those in the crude oil samples. The compositions of petroleum hydrocarbon in soil samples differed from those in crude oil, which indicated the n-alkanes with carbon numbers contaminated soils, the relationship between the index and petroleum hydrocarbon compounds was analyzed using principal component analysis (PCA). The results showed that the n-alkanes with carbon numbers > 33 and the PAHs with rings between 3 and 5 were much harder to degrade. PCA of 4 indexes for source identification revealed more than 50% of the soil samples were polluted by crude oil, which needs more attention during remediation.

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

Culture-Dependent and -Independent Methods Capture Different Microbial Community Fractions in Hydrocarbon-Contaminated Soils.

Directory of Open Access Journals (Sweden)

Franck O P Stefani

Full Text Available Bioremediation is a cost-effective and sustainable approach for treating polluted soils, but our ability to improve on current bioremediation strategies depends on our ability to isolate microorganisms from these soils. Although culturing is widely used in bioremediation research and applications, it is unknown whether the composition of cultured isolates closely mirrors the indigenous microbial community from contaminated soils. To assess this, we paired culture-independent (454-pyrosequencing of total soil DNA with culture-dependent (isolation using seven different growth media techniques to analyse the bacterial and fungal communities from hydrocarbon-contaminated soils. Although bacterial and fungal rarefaction curves were saturated for both methods, only 2.4% and 8.2% of the bacterial and fungal OTUs, respectively, were shared between datasets. Isolated taxa increased the total recovered species richness by only 2% for bacteria and 5% for fungi. Interestingly, none of the bacteria that we isolated were representative of the major bacterial OTUs recovered by 454-pyrosequencing. Isolation of fungi was moderately more effective at capturing the dominant OTUs observed by culture-independent analysis, as 3 of 31 cultured fungal strains ranked among the 20 most abundant fungal OTUs in the 454-pyrosequencing dataset. This study is one of the most comprehensive comparisons of microbial communities from hydrocarbon-contaminated soils using both isolation and high-throughput sequencing methods.

Culture-Dependent and -Independent Methods Capture Different Microbial Community Fractions in Hydrocarbon-Contaminated Soils.

Science.gov (United States)

Stefani, Franck O P; Bell, Terrence H; Marchand, Charlotte; de la Providencia, Ivan E; El Yassimi, Abdel; St-Arnaud, Marc; Hijri, Mohamed

2015-01-01

Bioremediation is a cost-effective and sustainable approach for treating polluted soils, but our ability to improve on current bioremediation strategies depends on our ability to isolate microorganisms from these soils. Although culturing is widely used in bioremediation research and applications, it is unknown whether the composition of cultured isolates closely mirrors the indigenous microbial community from contaminated soils. To assess this, we paired culture-independent (454-pyrosequencing of total soil DNA) with culture-dependent (isolation using seven different growth media) techniques to analyse the bacterial and fungal communities from hydrocarbon-contaminated soils. Although bacterial and fungal rarefaction curves were saturated for both methods, only 2.4% and 8.2% of the bacterial and fungal OTUs, respectively, were shared between datasets. Isolated taxa increased the total recovered species richness by only 2% for bacteria and 5% for fungi. Interestingly, none of the bacteria that we isolated were representative of the major bacterial OTUs recovered by 454-pyrosequencing. Isolation of fungi was moderately more effective at capturing the dominant OTUs observed by culture-independent analysis, as 3 of 31 cultured fungal strains ranked among the 20 most abundant fungal OTUs in the 454-pyrosequencing dataset. This study is one of the most comprehensive comparisons of microbial communities from hydrocarbon-contaminated soils using both isolation and high-throughput sequencing methods.

Bacterial Endophytes Isolated from Plants in Natural Oil Seep Soils with Chronic Hydrocarbon Contamination.

Science.gov (United States)

Lumactud, Rhea; Shen, Shu Yi; Lau, Mimas; Fulthorpe, Roberta

2016-01-01

The bacterial endophytic communities of four plants growing abundantly in soils highly contaminated by hydrocarbons were analyzed through culturable and culture-independent means. Given their tolerance to the high levels of petroleum contamination at our study site, we sought evidence that Achillea millefolium, Solidago canadensis, Trifolium aureum, and Dactylis glomerata support high levels of hydrocarbon degrading endophytes. A total of 190 isolates were isolated from four plant species. The isolates were identified by partial 16S rDNA sequence analysis, with class Actinobacteria as the dominant group in all species except S. canadensis, which was dominated by Gammaproteobacteria. Microbacterium foliorum and Plantibacter flavus were present in all the plants, with M. foliorum showing predominance in D. glomerata and both endophytic bacterial species dominated T. aureum. More than 50% of the isolates demonstrated degradative capabilities for octanol, toluene, naphthalene, kerosene, or motor oil based on sole carbon source growth screens involving the reduction of tetrazolium dye. P. flavus isolates from all the sampled plants showed growth on all the petroleum hydrocarbons (PHCs) substrates tested. Mineralization of toluene and naphthalene was confirmed using gas-chromatography. 16S based terminal restriction fragment length polymorphism analysis revealed significant differences between the endophytic bacterial communities showing them to be plant host specific at this site. To our knowledge, this is the first account of the degradation potential of bacterial endophytes in these commonly occurring pioneer plants that were not previously known as phytoremediating plants.

Bacterial endophytes isolated from plants in natural oil seep soils with chronic hydrocarbon contamination

Directory of Open Access Journals (Sweden)

Rhea eLumactud

2016-05-01

Full Text Available The bacterial endophytic communities of four plants growing abundantly in soils highly contaminated by hydrocarbons were analyzed through culturable and and culture-independent means. Given their tolerance to the high levels of petroleum contamination at our study site, we sought evidence that Achillea millefolium, Solidago canadensis, Trifolium aureum and Dactylis glomerata support high levels of hydrocarbon degrading endophytes. A total of 190 isolates were isolated from four plant species. The isolates were identified by partial 16S rDNA sequence analysis, with class Actinobacteria as the dominant group in all species except Solidago canadensis, which was dominated by Gammaproteobacteria. Microbacterium foliorum and Plantibacter flavus were present in all the plants, with M. foliorum showing predominance in D. glomerata and both endophytic bacterial species dominated T. aureum. More than 50% of the isolates demonstrated degradative capabilities for octanol, toluene, naphthalene, kerosene or motor oil based on sole carbon source growth screens involving the reduction of tetrazolium dye. P. flavus isolates from all the sampled plants showed growth on all the petroleum hydrocarbons substrates tested. Mineralization of toluene and naphthalene was confirmed using gas-chromatography. 16S based terminal restriction fragment length polymorphism analysis revealed significant differences between the endophytic bacterial communities showing them to be plant host specific at this site. To our knowledge, this is the first account of the degradation potential of bacterial endophytes in these commonly occurring pioneer plants that were not previously known as phytoremediating plants.

Monitoring biodegradation of ethene and bioremediation of chlorinated ethenes at a contaminated site using compound-specific isotope analysis (CSIA).

Science.gov (United States)

Mundle, Scott O C; Johnson, Tiffany; Lacrampe-Couloume, Georges; Pérez-de-Mora, Alfredo; Duhamel, Melanie; Edwards, Elizabeth A; McMaster, Michaye L; Cox, Evan; Révész, Kinga; Sherwood Lollar, Barbara

2012-02-07

Chlorinated ethenes are commonly found in contaminated groundwater. Remediation strategies focus on transformation processes that will ultimately lead to nontoxic products. A major concern with these strategies is the possibility of incomplete dechlorination and accumulation of toxic daughter products (cis-1,2-dichloroethene (cDCE), vinyl chloride (VC)). Ethene mass balance can be used as a direct indicator to assess the effectiveness of dechlorination. However, the microbial processes that affect ethene are not well characterized and poor mass balance may reflect biotransformation of ethene rather than incomplete dechlorination. Microbial degradation of ethene is commonly observed in aerobic systems but fewer cases have been reported in anaerobic systems. Limited information is available on the isotope enrichment factors associated with these processes. Using compound-specific isotope analysis (CSIA) we determined the enrichment factors associated with microbial degradation of ethene in anaerobic microcosms (ε = -6.7‰ ± 0.4‰, and -4.0‰ ± 0.8‰) from cultures collected from the Twin Lakes wetland area at the Savannah River site in Georgia (United States), and in aerobic microcosms (ε = -3.0‰ ± 0.3‰) from Mycobacterium sp. strain JS60. Under anaerobic and aerobic conditions, CSIA can be used to determine whether biotransformation of ethene is occurring in addition to biodegradation of the chlorinated ethenes. Using δ(13)C values determined for ethene and for chlorinated ethenes at a contaminated field site undergoing bioremediation, this study demonstrates how CSIA of ethene can be used to reduce uncertainty and risk at a site by distinguishing between actual mass balance deficits during reductive dechlorination and apparent lack of mass balance that is related to biotransformation of ethene.

Activity and functional diversity of microbial communities in long-term hydrocarbon and heavy metal contaminated soils

Directory of Open Access Journals (Sweden)

Markowicz Anna

2016-12-01

Full Text Available The impacts of long-term polycyclic aromatic hydrocarbons (PAHs and heavy metal pollution on soil microbial communities functioning were studied in soils taken from an old coke plant. The concentrations of PAHs in the tested soils ranged from 171 to 2137 mg kg-1. From the group of tested heavy metals, concentrations of lead were found to be the highest, ranging from 57 to 3478 mg kg-1, while zinc concentrations varied from 247 to 704 mg kg-1 and nickel from 10 to 666 mg kg-1. High dehydrogenase, acid and alkaline phosphatase activities were observed in the most contaminated soil. This may indicate bacterial adaptation to long-term heavy metal and hydrocarbon contamination. However, the Community Level Physiological Profiles (CLPPs analysis showed that the microbial functional diversity was reduced and influenced to a higher extent by some metals (Pb, Ni, moisture and conductivity than by PAHs.

In situ phytoremediation of a soil historically contaminated by metals, hydrocarbons and polychlorobiphenyls.

Science.gov (United States)

Doni, S; Macci, C; Peruzzi, E; Arenella, M; Ceccanti, B; Masciandaro, G

2012-05-01

In the past several years, industrial and agricultural activities have led to serious environmental pollution, resulting in a large number of contaminated sites. As a result, much recent research activity has focused on the application of bioremediation technologies as an environmentally friendly and economically feasible means for decontamination of polluted soil. In this study horse manure and Populus nigra (var. italica) (HM + P treatment) have been used, at real scale level, as an approach for bioremediation of a soil historically contaminated by metals (Pb, Cr, Cd, Zn, Cu and Ni) and organic contaminants, such as polychlorobiphenyls and petroleum hydrocarbon. After one year, the HM + P phytotreatment was effective in the reclamation of the polluted soil from both organic and inorganic contaminants. A reduction of about 80% in total petroleum hydrocarbon (TPH), and 60% in polychlorobiphenyls (PCBs) and total metals was observed in the HM + P treatment. In contrast, in the horse manure (HM) treatment, used as control, a reduction of only about 30% of TPH was obtained. In order to assess both effectiveness and evolution of the remediation system to a biologically active soil ecosystem, together with the pollution parameters, the parameters describing the evolution of the soil functionality (enzymatic activities and protein SDS-PAGE pattern) were investigated. A stimulation of the metabolic soil processes (increase in dehydrogenase activity) was observed in the HM + P compared to the HM treatment. Finally, preliminary protein SDS-PAGE results have permitted the identification of proteins that have been recovered in the HM + P soil with respect to the HM; this may become a basic tool for improving the biogeochemical status of soil during the decontamination through the identification of microbial populations that are active in soil decontamination.

Compost bioremediation of hydrocarbon-contaminated soil ...

African Journals Online (AJOL)

STORAGESEVER

2008-05-16

May 16, 2008 ... The use of composting in bioremediation has received little attention (Potter et al., ..... Counts of microorganisms in the compost during composting. Values are means of three ..... chlorinated pesticides. J. Water Poll. Cont. Fed.

Combination of biochar amendment and phytoremediation for hydrocarbon removal in petroleum-contaminated soil

OpenAIRE

Han, Tao; Zhao, Zhipeng; Bartlam, Mark; Wang, Yingying

2016-01-01

Remediation of soils contaminated with petroleum is a challenging task. Four different bioremediation strategies, including natural attenuation, biochar amendment, phytoremediation with ryegrass, and a combination of biochar and ryegrass, were investigated with greenhouse pot experiments over a 90-day period. The results showed that planting ryegrass in soil can significantly improve the removal rate of total petroleum hydrocarbons (TPHs) and the number of microorganisms. Within TPHs, the rem...

Arbuscular mycorrhizal wheat inoculation promotes alkane and polycyclic aromatic hydrocarbon biodegradation: Microcosm experiment on aged-contaminated soil

International Nuclear Information System (INIS)

Ingrid, Lenoir; Lounès-Hadj Sahraoui, Anissa; Frédéric, Laruelle; Yolande, Dalpé; Joël, Fontaine

2016-01-01

Very few studies reported the potential of arbuscular mycorrhizal symbiosis to dissipate hydrocarbons in aged polluted soils. The present work aims to study the efficiency of arbuscular mycorrhizal colonized wheat plants in the dissipation of alkanes and polycyclic aromatic hydrocarbons (PAHs). Our results demonstrated that the inoculation of wheat with Rhizophagus irregularis allowed a better dissipation of PAHs and alkanes after 16 weeks of culture by comparison to non-inoculated condition. These dissipations observed in the inoculated soil resulted from several processes: (i) a light adsorption on roots (0.5% for PAHs), (ii) a bioaccumulation in roots (5.7% for PAHs and 6.6% for alkanes), (iii) a transfer in shoots (0.4 for PAHs and 0.5% for alkanes) and mainly a biodegradation. Whereas PAHs and alkanes degradation rates were respectively estimated to 12 and 47% with non-inoculated wheat, their degradation rates reached 18 and 48% with inoculated wheat. The mycorrhizal inoculation induced an increase of Gram-positive and Gram-negative bacteria by 56 and 37% compared to the non-inoculated wheat. Moreover, an increase of peroxidase activity was assessed in mycorrhizal roots. Taken together, our findings suggested that mycorrhization led to a better hydrocarbon biodegradation in the aged-contaminated soil thanks to a stimulation of telluric bacteria and hydrocarbon metabolization in mycorrhizal roots. - Highlights: • Phytoremediation of aged-hydrocarbon polluted soils may be improved using arbuscular mycorrhizal fungi. • Inoculation of wheat with R. irregularis improved dissipation of PAH and alkanes. • Dissipation resulted from adsorption and bioaccumulation in wheat and mainly from biodegradation in soil. • Biodegradation was due to a stimulation of rhizosphere bacteria and an induction of root peroxidase. - Inoculation of wheat by an arbuscular mycorrhizal fungus improves biodegradation of alkanes and polycyclic aromatic hydrocarbons in an aged-contaminated

Phytoremediation mechanisms for polycyclic aromatic hydrocarbons removing from contaminated soils

Directory of Open Access Journals (Sweden)

Alagić Slađana Č.

2015-01-01

Full Text Available Phytoremediation of polycyclic aromatic hydrocarbons (PAHs from soil aims to degrade them into less toxic/non toxic compounds and limit their further movement by sequestration and accumulation into the vacuoles. Lipophilic organic compounds such as PAHs are bound strongly to the epidermis of the root tissue and are rarely translocated within plant. There are no reports in the literature data of PAHs being completely mineralized by plants. There is little evidence to suggest that PAHs accumulate to significant degree in plants, but there still is a lot of evidences on the ability of various plant species (most often grasses and legumes, to degrade and dissipate these dangerous contaminants. The primary mechanism controlling the dissipation of PAHs is rhizosphere microbial degradation where microbes use PAHs molecules as carbon substrates for growth, which in final, leads to the breakdown or total mineralization of the contaminants. The process is usually augmented by the excretion of root exudates (e.g., sugars, alcohols, acids, enzymes, and the build-up of organic carbon in the soil, so the proper selection of particular plant species represents a critical management decision for PAHs phytoremediation. These facts favor the rhyzoremediation as the best solution for sites contaminated with PAHs.

Germination of Lepidium sativum as a method to evaluate polycyclic aromatic hydrocarbons (PAHs) removal from contaminated soil

CSIR Research Space (South Africa)

Maila, MP

2002-01-01

Full Text Available The sensitivity of Lepidium sativum germination to polycyclic aromatic hydrocarbons (PAHs) was investigated in soil(s) artificially and historically contaminated with mixtures of PAR The level of germination of L. sativum decreased with increasing...

Aerobic biodegradation of a mixture of chlorinated organics in ...

African Journals Online (AJOL)

STORAGESEVER

2008-07-04

Jul 4, 2008 ... DCM; and 0.232 – 0.588 week-1 for DCA in both water microcosms with higher degradation generally observed in New ... Key words: Bioaugmentation, biodegradation, biostimulation, chlorinated aliphatic hydrocarbons, microcosms. ... culture (OD of 1 at λ600) of the consortia was added separately to.

Environmental Analysis of Endocrine Disrupting Effects from Hydrocarbon Contaminants in the Ecosystem - Final Report - 09/15/1996 - 09/14/2000

International Nuclear Information System (INIS)

McLachlan, John A.

2000-01-01

The three major components of the research included: (a) a biotechnology based screening system to identify potential hormone mimics and antagonists (b) an animal screening system to identify biomarkers of endocrine effects and (c) a literature review to identify compounds at various DOE sites that are potential endocrine disruptors. Species of particular interest in this study were those that can serve as sentinel species (e.g., amphibians) and thus provide early warning signals for more widespread impacts on an ecosystem and its wildlife and human inhabitants. The objective of this basic research is to characterize the potential of common hydrocarbon contaminants in ecosystems to act as endocrine disruptors. Although the endocrine disrupting effects of contaminants such as dioxin and PCBs have been well characterized in both animals and humans, little is known about the capacities of other hydrocarbon contaminants to act as endocrine disruptors. Results obtained from this research project have provided information on endocrine disrupting contaminants for consideration in DOE's risk analyses for determining clean-up levels and priorities at contaminated DOE sites

Environmental Analysis of Endocrine Disrupting Effects from Hydrocarbon Contaminants in the Ecosystem - Final Report - 09/15/1996 - 09/14/2000

Energy Technology Data Exchange (ETDEWEB)

McLachlan, John A.

2000-09-14

The three major components of the research included: (a) a biotechnology based screening system to identify potential hormone mimics and antagonists (b) an animal screening system to identify biomarkers of endocrine effects and (c) a literature review to identify compounds at various DOE sites that are potential endocrine disruptors. Species of particular interest in this study were those that can serve as sentinel species (e.g., amphibians) and thus provide early warning signals for more widespread impacts on an ecosystem and its wildlife and human inhabitants. The objective of this basic research is to characterize the potential of common hydrocarbon contaminants in ecosystems to act as endocrine disruptors. Although the endocrine disrupting effects of contaminants such as dioxin and PCBs have been well characterized in both animals and humans, little is known about the capacities of other hydrocarbon contaminants to act as endocrine disruptors. Results obtained from this research project have provided information on endocrine disrupting contaminants for consideration in DOE's risk analyses for determining clean-up levels and priorities at contaminated DOE sites.

Cost and Performance Report of Dissolved Hydrogen Analyzer

National Research Council Canada - National Science Library

Lebron, Carmen A; Sugiyama, Barbara; Evans, Patrick J; Trute, Mary; Olsen, Roger

2005-01-01

.... Department of Defense (DOD). Monitored natural attenuation can be used to mitigate petroleum hydrocarbon, chlorinated hydrocarbon, and metal-contaminated sites as an alternative to groundwater pump and treat methods...

Performance studies of an IR fiber optic sensor for chlorinated hydrocarbons in water

International Nuclear Information System (INIS)

Goebel, R.; Krska, R.; Neal, S.; Kellner, R.

1994-01-01

Chlorinated hydrocarbons (CHCs) were monitored using a recently presented infrared fiber-optic physico-chemical sensor consisting of an MIR transparent, polymer coated, silver halide fiber coupled to a commercial FTIR spectrometer. The aim of this study was to test the performance of this new fiber optic sensing device with respect to temperature dependence, simultaneous detection of several CHCs, sensitivity and dynamic response behavior. In addition the diffusion process of the CHCs into the polymer was analyzed in order to better understand and evaluate the obtained results. During the investigation of the temperature dependence of the sensor response to real trend could be observed in the temperature range of 0 to 22 C. The dynamic response of the sensor is in the minute range when experiencing an increase in concentration of the analyte while with a decrease in concentration, the response is relatively slow. The sensor enabled the detection of 10 environmentally relevant CHCs at concentrations of 1 to 50 ppm. The simulation of the experimental diffusion data revealed Fick's 1st law diffusion for CHCs into the polymer layers. Finally the sensing device was validated with head spacegas chromatography (HSGC) analyses and showed good agreement with these already established methods. This work shows the great potential of IR fiber optic sensors as early warning systems for a variety of CHCs in water (''threshold alarm sensor'') (orig.)

Insights into the biodegradation of weathered hydrocarbons in contaminated soils by bioaugmentation and nutrient stimulation.

Science.gov (United States)

Jiang, Ying; Brassington, Kirsty J; Prpich, George; Paton, Graeme I; Semple, Kirk T; Pollard, Simon J T; Coulon, Frédéric

2016-10-01

The potential for biotransformation of weathered hydrocarbon residues in soils collected from two commercial oil refinery sites (Soil A and B) was studied in microcosm experiments. Soil A has previously been subjected to on-site bioremediation and it was believed that no further degradation was possible while soil B has not been subjected to any treatment. A number of amendment strategies including bioaugmentation with hydrocarbon degrader, biostimulation with nutrients and soil grinding, were applied to the microcosms as putative biodegradation improvement strategies. The hydrocarbon concentrations in each amendment group were monitored throughout 112 days incubation. Microcosms treated with biostimulation (BS) and biostimulation/bioaugmentation (BS + BA) showed the most significant reductions in the aliphatic and aromatic hydrocarbon fractions. However, soil grinding was shown to reduce the effectiveness of a nutrient treatment on the extent of biotransformation by up to 25% and 20% for the aliphatic and aromatic hydrocarbon fractions, respectively. This is likely due to the disruption to the indigenous microbial community in the soil caused by grinding. Further, ecotoxicological responses (mustard seed germination and Microtox assays) showed that a reduction of total petroleum hydrocarbon (TPH) concentration in soil was not directly correlable to reduction in toxicity; thus monitoring TPH alone is not sufficient for assessing the environmental risk of a contaminated site after remediation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

On the efficiency of the hybrid and the exact second-order sampling formulations of the EnKF: a reality-inspired 3-D test case for estimating biodegradation rates of chlorinated hydrocarbons at the port of Rotterdam

KAUST Repository

El Gharamti, Mohamad

2016-11-15

This study considers the assimilation problem of subsurface contaminants at the port of Rotterdam in the Netherlands. It involves the estimation of solute concentrations and biodegradation rates of four different chlorinated solvents. We focus on assessing the efficiency of an adaptive hybrid ensemble Kalman filter and optimal interpolation (EnKF-OI) and the exact second-order sampling formulation (EnKFESOS) for mitigating the undersampling of the estimation and observation errors covariances, respectively. A multi-dimensional and multi-species reactive transport model is coupled to simulate the migration of contaminants within a Pleistocene aquifer layer located around 25 m below mean sea level. The biodegradation chain of chlorinated hydrocarbons starting from tetrachloroethene and ending with vinyl chloride is modeled under anaerobic environmental conditions for 5 decades. Yearly pseudo-concentration data are used to condition the forecast concentration and degradation rates in the presence of model and observational errors. Assimilation results demonstrate the robustness of the hybrid EnKF-OI, for accurately calibrating the uncertain biodegradation rates. When implemented serially, the adaptive hybrid EnKF-OI scheme efficiently adjusts the weights of the involved covariances for each individual measurement. The EnKFESOS is shown to maintain the parameter ensemble spread much better leading to more robust estimates of the states and parameters. On average, a well tuned hybrid EnKF-OI and the EnKFESOS respectively suggest around 48 and 21 % improved concentration estimates, as well as around 70 and 23 % improved anaerobic degradation rates, over the standard EnKF. Incorporating large uncertainties in the flow model degrades the accuracy of the estimates of all schemes. Given that the performance of the hybrid EnKF-OI depends on the quality of the background statistics, satisfactory results were obtained only when the uncertainty imposed on the background

Laboratory-Scale Simulation and Real-Time Tracking of a Microbial Contamination Event and Subsequent Shock-Chlorination in Drinking Water

Directory of Open Access Journals (Sweden)

Michael D. Besmer

2017-10-01

Full Text Available Rapid contamination of drinking water in distribution and storage systems can occur due to pressure drop, backflow, cross-connections, accidents, and bio-terrorism. Small volumes of a concentrated contaminant (e.g., wastewater can contaminate large volumes of water in a very short time with potentially severe negative health impacts. The technical limitations of conventional, cultivation-based microbial detection methods neither allow for timely detection of such contaminations, nor for the real-time monitoring of subsequent emergency remediation measures (e.g., shock-chlorination. Here we applied a newly developed continuous, ultra high-frequency flow cytometry approach to track a rapid pollution event and subsequent disinfection of drinking water in an 80-min laboratory scale simulation. We quantified total (TCC and intact (ICC cell concentrations as well as flow cytometric fingerprints in parallel in real-time with two different staining methods. The ingress of wastewater was detectable almost immediately (i.e., after 0.6% volume change, significantly changing TCC, ICC, and the flow cytometric fingerprint. Shock chlorination was rapid and detected in real time, causing membrane damage in the vast majority of bacteria (i.e., drop of ICC from more than 380 cells μl-1 to less than 30 cells μl-1 within 4 min. Both of these effects as well as the final wash-in of fresh tap water followed calculated predictions well. Detailed and highly quantitative tracking of microbial dynamics at very short time scales and for different characteristics (e.g., concentration, membrane integrity is feasible. This opens up multiple possibilities for targeted investigation of a myriad of bacterial short-term dynamics (e.g., disinfection, growth, detachment, operational changes both in laboratory-scale research and full-scale system investigations in practice.

The use of comprehensive two-dimensional gas chromatography and structure-activity modeling for screening and preliminary risk assessment of organic contaminants in soil, sediment, and surface water

Energy Technology Data Exchange (ETDEWEB)

Moreira Bastos, Patricia; Haglund, Peter [Umeaa Univ. (Sweden). Dept. of Chemistry

2012-08-15

Purpose: This article aims to investigate the use and benefits of using comprehensive two-dimensional gas chromatography (GC x GC) and structure-activity relationship modeling for screening and prioritization of organic contaminants in complex matrices. The benefit of applying comprehensive screening techniques to samples with high organic contaminant content is primarily that compounds with diverse physicochemical properties can be analyzed simultaneously. Here, a heavily contaminated industrial area was surveyed for organic pollutants by analyzing soil, sediment, and surface water samples. The hazard of the pollutants were ranked using SARs. Material and methods: The water samples were liquid-liquid extracted using dichloromethane and directly analyzed by GC x GC-time-of-flight mass spectrometry (GC x GC-TofMS). Soil and sediment samples were extracted with dichloromethane in an ultrasonic bath and subjected to gel permeation chromatography to eliminate lipids and humic matter. The low molecular weight fraction was then analyzed with GC x GC-TofMS. Results and discussion: More than 10,000 components were found in each sample, of which ca. 300 individual compounds were unambiguously identified using the National Institute of Standards and Technology mass spectra library and authentic reference standards. Alkanes, polycyclic aromatic hydrocarbons, and phthalates were generally the most abundant and were found in all matrices. In contrast, chlorinated compounds such as chlorophenols, biphenyls, and chlorinated pesticides were only detected in samples from a few hotspot regions. The toxicities of the most frequently detected compounds and of the compounds detected at the highest concentrations in samples from hotspot regions were estimated by ecological structure-activity relationships. The ratio of the measured concentration to the predicted toxicity level was then calculated for each compound and used for an initial risk assessment in order to prioritize compounds

Distribution of polychlorinated biphenyls, phthalic acid esters, polycyclic aromatic hydrocarbons and organochlorine substances in the Moscow River, Russia

International Nuclear Information System (INIS)

Eremina, Natalia; Paschke, Albrecht; Mazlova, Elena A.; Schüürmann, Gerrit

2016-01-01

The purpose of this study was to investigate the levels of polychlorinated biphenyl (PCB), phthalic acid esters (PAE), polycyclic aromatic hydrocarbons (PAH) and organochlorine substances (OCP) in the Moscow River water. Some studies have reported the occurrence of these substances in the soil of the Moscow region; however, no study has yet established an overview for these compounds in the Moscow River water. In this study the Moscow River water contamination with PAEs, PAHs and OCPs was determined. Obtained results were associated with the resident area located on the river bank, and the possible contamination sources were considered. The obtained data were compared with the data on the contamination of the different world-wide rivers. This research indicates the further study necessity of the Moscow region to cover more contaminated sites and environmental compartments. - Highlights: • The monitoring system creation of the Moscow River is necessary. • The wastewater plant is the source of the river contamination with triclosan. • The Moscow River is contaminated with the low chlorinated biphenyls. • There is a background contamination of the Moscow River with phthalates. - The organic pollutants contamination levels of the Moscow River were investigated.

[Improving Agricultural Safety of Soils Contaminated with Polycyclic Aromatic Hydrocarbons by In Situ Bioremediation].

Science.gov (United States)

Jiao, Hai-huan; Pan, Jian-gang; Xu, Shena-jun; Bai, Zhi-hui; Wang, Dong; Huang, Zhan-bin

2015-08-01

In order to reduce the risk of enrichment of polycyclic aromatic hydrocarbons (PAHs) in crops, reduce the potential hazards of food-sourced PAHs to human and increase the agricultural safety of PAHs contaminated soils, the bio-augmented removal of polycyclic aromatic hydrocarbons (PAHs) was investigated through in situ remediation by introducing Rhodobacter sphaeroides (RS) into the agricultural soil contaminated by PAHs. The 50-times diluted RS was sprayed on leaf surface (in area B) or irrigated to roots (in area D). The treatment of spraying water of the equal amount was taken as the control (A) and the wheat field without any treatment as the blank (CK). Treatments were conducted since wheat seeding. Soil and wheat samples were collected in the mature period to analyze the changes of community structure of the soil microorganisms and the concentration of PAHs in soils and investigate the strengthening and restoration effects of RS on PAHs contaminated soils. Compared to the CK Area, the areas B and D revealed that the variation ratio of phospholipid fatty acids (PLFAs) that were the biomarker of soil microorganisms was 29.6%, and the ratio of total PAHs removed was increased 1.59 times and 1.68 times, respectively. The dry weight of wheat grain of 50 spikes was increased by 8.95% and 12.5%, respectively, and the enrichment factor of total PAHs was decreased by 58.9% and 62.2% respectively in the wheat grains. All the results suggested that RS reduced enrichment of PAHs in wheat grains and increased wheat yield, which had great exploitation and utilization potentiality in repairing and improving the agricultural safety of the soils contaminated with PHAs.

Enhanced metabolism of halogenated hydrocarbons in transgenic plants containing mammalian cytochrome P450 2E1

Science.gov (United States)

Lafferty Doty, Sharon; Shang, Tanya Q.; Wilson, Angela M.; Tangen, Jeff; Westergreen, Aram D.; Newman, Lee A.; Strand, Stuart E.; Gordon, Milton P.

2000-06-01

Chlorinated solvents, especially trichloroethylene (TCE), are the most widespread groundwater contaminants in the United States. Existing methods of pumping and treating are expensive and laborious. Phytoremediation, the use of plants for remediation of soil and groundwater pollution, is less expensive and has low maintenance; however, it requires large land areas and there are a limited number of suitable plants that are known to combine adaptation to a particular environment with efficient metabolism of the contaminant. In this work, we have engineered plants with a profound increase in metabolism of the most common contaminant, TCE, by introducing the mammalian cytochrome P450 2E1. This enzyme oxidizes a wide range of important pollutants, including TCE, ethylene dibromide, carbon tetrachloride, chloroform, and vinyl chloride. The transgenic plants had a dramatic enhancement in metabolism of TCE of up to 640-fold as compared with null vector control plants. The transgenic plants also showed an increased uptake and debromination of ethylene dibromide. Therefore, transgenic plants with this enzyme could be used for more efficient remediation of many sites contaminated with halogenated hydrocarbons.

Linkage between bacterial and fungal rhizosphere communities in hydrocarbon-contaminated soils is related to plant phylogeny.

Science.gov (United States)

Bell, Terrence H; El-Din Hassan, Saad; Lauron-Moreau, Aurélien; Al-Otaibi, Fahad; Hijri, Mohamed; Yergeau, Etienne; St-Arnaud, Marc

2014-02-01

Phytoremediation is an attractive alternative to excavating and chemically treating contaminated soils. Certain plants can directly bioremediate by sequestering and/or transforming pollutants, but plants may also enhance bioremediation by promoting contaminant-degrading microorganisms in soils. In this study, we used high-throughput sequencing of bacterial 16S rRNA genes and the fungal internal transcribed spacer (ITS) region to compare the community composition of 66 soil samples from the rhizosphere of planted willows (Salix spp.) and six unplanted control samples at the site of a former petrochemical plant. The Bray-Curtis distance between bacterial communities across willow cultivars was significantly correlated with the distance between fungal communities in uncontaminated and moderately contaminated soils but not in highly contaminated (HC) soils (>2000 mg kg(-1) hydrocarbons). The mean dissimilarity between fungal, but not bacterial, communities from the rhizosphere of different cultivars increased substantially in the HC blocks. This divergence was partly related to high fungal sensitivity to hydrocarbon contaminants, as demonstrated by reduced Shannon diversity, but also to a stronger influence of willows on fungal communities. Abundance of the fungal class Pezizomycetes in HC soils was directly related to willow phylogeny, with Pezizomycetes dominating the rhizosphere of a monophyletic cluster of cultivars, while remaining in low relative abundance in other soils. This has implications for plant selection in phytoremediation, as fungal associations may affect the health of introduced plants and the success of co-inoculated microbial strains. An integrated understanding of the relationships between fungi, bacteria and plants will enable the design of treatments that specifically promote effective bioremediating communities.

Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents

KAUST Repository

Wadsworth, Andrew; Ashraf, Raja; Abdelsamie, Maged; Pont, Sebastian; Little, Mark; Moser, Maximilian; Hamid, Zeinab; Neophytou, Marios; Zhang, Weimin; Amassian, Aram; Durrant, James R.; Baran, Derya; McCulloch, Iain

2017-01-01

With chlorinated solvents unlikely to be permitted for use in solution-processed organic solar cells in industry, there must be a focus on developing nonchlorinated solvent systems. Here we report high-efficiency devices utilizing a low-bandgap donor polymer (PffBT4T-2DT) and a nonfullerene acceptor (EH-IDTBR) from hydrocarbon solvents and without using additives. When mesitylene was used as the solvent, rather than chlorobenzene, an improved power conversion efficiency (11.1%) was achieved without the need for pre- or post-treatments. Despite altering the processing conditions to environmentally friendly solvents and room-temperature coating, grazing incident X-ray measurements confirmed that active layers processed from hydrocarbon solvents retained the robust nanomorphology obtained with hot-processed chlorinated solvents. The main advantages of hydrocarbon solvent-processed devices, besides the improved efficiencies, were the reproducibility and storage lifetime of devices. Mesitylene devices showed better reproducibility and shelf life up to 4000 h with PCE dropping by only 8% of its initial value.

Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents

KAUST Repository

Wadsworth, Andrew

2017-06-01

With chlorinated solvents unlikely to be permitted for use in solution-processed organic solar cells in industry, there must be a focus on developing nonchlorinated solvent systems. Here we report high-efficiency devices utilizing a low-bandgap donor polymer (PffBT4T-2DT) and a nonfullerene acceptor (EH-IDTBR) from hydrocarbon solvents and without using additives. When mesitylene was used as the solvent, rather than chlorobenzene, an improved power conversion efficiency (11.1%) was achieved without the need for pre- or post-treatments. Despite altering the processing conditions to environmentally friendly solvents and room-temperature coating, grazing incident X-ray measurements confirmed that active layers processed from hydrocarbon solvents retained the robust nanomorphology obtained with hot-processed chlorinated solvents. The main advantages of hydrocarbon solvent-processed devices, besides the improved efficiencies, were the reproducibility and storage lifetime of devices. Mesitylene devices showed better reproducibility and shelf life up to 4000 h with PCE dropping by only 8% of its initial value.

Mutagenic hazards of complex polycyclic aromatic hydrocarbon mixtures in contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Lemieux, C.L.; Lambert, A.B.; Lundstedt, S.; Tysklind, M.; White, P.A. [Health Canada, Ottawa, ON (Canada). Safe Environment Program

2008-04-15

The objective of the present study was to evaluate hazard/risk assessment methods for complex environmental mixtures that involve a targeted, priority chemical approach based on the cumulative hazard/risk of known mixture components or analyses of sufficiently similar mixtures. Ten polycyclic aromatic hydrocarbon (PAH)-contaminated soils were separated into nonpolar and semipolar fractions, and both fractions elicited positive responses on the Salmonella reverse mutation assay. Targeted and nontargeted methods of hazard prediction routinely overestimated mutagenic activities for the nonpolar soil fractions, suggesting nonadditive interactions of PAHs in complex mixtures. This suggests that current risk assessment methods for complex mixtures may provide conservative estimates regarding soils contaminated with priority PAHs alone. Significant underestimations of total risk, however, will be obtained if the soils also contain unidentified PAHs as well as polycyclic aromatic compounds and related compounds that contribute to the total mutagenic activity. Furthermore, estimates of excess lifetime cancer risk associated with the nondietary ingestion of the PAH-contaminated soils studied here indicate that a traditional risk assessment model based on identified priority PAHs and an assumption of additivity generally underestimates the risk associated with the nonpolar soil fractions (in comparison to bioassay-derived risk estimates). Additional cancer risk may be associated with the more polar compounds that also are found at these contaminated sites and that rarely are included in the standard risk assessment methodology.

The ecological and physiological responses of the microbial community from a semiarid soil to hydrocarbon contamination and its bioremediation using compost amendment.

Science.gov (United States)

Bastida, F; Jehmlich, N; Lima, K; Morris, B E L; Richnow, H H; Hernández, T; von Bergen, M; García, C

2016-03-01

The linkage between phylogenetic and functional processes may provide profound insights into the effects of hydrocarbon contamination and biodegradation processes in high-diversity environments. Here, the impacts of petroleum contamination and the bioremediation potential of compost amendment, as enhancer of the microbial activity in semiarid soils, were evaluated in a model experiment. The analysis of phospholipid fatty-acids (PLFAs) and metaproteomics allowed the study of biomass, phylogenetic and physiological responses of the microbial community in polluted semiarid soils. Petroleum pollution induced an increase of proteobacterial proteins during the contamination, while the relative abundance of Rhizobiales lowered in comparison to the non-contaminated soil. Despite only 0.55% of the metaproteome of the compost-treated soil was involved in biodegradation processes, the addition of compost promoted the removal of polycyclic aromatic hydrocarbons (PAHs) and alkanes up to 88% after 50 days. However, natural biodegradation of hydrocarbons was not significant in soils without compost. Compost-assisted bioremediation was mainly driven by Sphingomonadales and uncultured bacteria that showed an increased abundance of catabolic enzymes such as catechol 2,3-dioxygenases, cis-dihydrodiol dehydrogenase and 2-hydroxymuconic semialdehyde. For the first time, metaproteomics revealed the functional and phylogenetic relationships of petroleum contamination in soil and the microbial key players involved in the compost-assisted bioremediation. Copyright © 2015 Elsevier B.V. All rights reserved.

Monitoring of the aerobe biodegradation of chlorinated organic solvents by stable isotope analysis

Science.gov (United States)

Horváth, Anikó; Futó, István; Palcsu, László

2014-05-01

Our chemical-biological basic research aims to eliminate chlorinated environmental contaminants from aquifers around industrial areas in the frame of research program supported by the European Social Fund (TÁMOP-4.2.2.A-11/1/KONV-2012-0043). The most careful and simplest way includes the in situ biodegradation with the help of cultured and compound specific strains. Numerous members of Pseudomonas bacteria are famous about function of bioremediation. They can metabolism the environmental hazardous chemicals like gas oils, dyes, and organic solvents. Our research based on the Pseudomonas putida F1 strain, because its ability to degrade halogenated hydrocarbons such as trichloroethylene. Several methods were investigated to estimate the rate of biodegradation, such as the measurement of the concentration of the pollutant along the contamination pathway, the microcosm's studies or the compound specific stable isotope analysis. In this area in the Transcarpathian basin we are pioneers in the stable isotope monitoring of biodegradation. The main goal is to find stable isotope fractionation factors by stable isotope analysis, which can help us to estimate the rate and effectiveness of the biodegradation. The subsequent research period includes the investigation of the method, testing its feasibility and adaptation in the environment. Last but not least, the research gives an opportunity to identify the producer of the contaminant based on the stable isotope composition of the contaminant.

Ranking harbours in the Maritime provinces of Canada for potential to contaminate American lobster (Homarus americanus) with polycyclic aromatic hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Prouse, N.J. [Department of Fisheries and Oceans, Halifax, NS (Canada). Biological Sciences Branch

1997-05-01

The sources of polycyclic aromatic hydrocarbon (PAH) contamination within selected harbors in the Maritime provinces of Canada were evaluated by assessing point sources, population, industrial and commercial activity, international and domestic ship traffic, and the number of commercial fishing vessels. Results showed that Sydney ranked as the highest potential for PAH contamination. Ranking of the other Maritime harbors was also presented. The lobster contamination with PAHs was reviewed.

Biological Remediation of Petroleum Contaminants

Science.gov (United States)

Kuhad, Ramesh Chander; Gupta, Rishi

Large volumes of hazardous wastes are generated in the form of oily sludges and contaminated soils during crude oil transportation and processing. Although many physical, chemical and biological treatment technologies are available for petroleum contaminants petroleum contaminants in soil, biological methods have been considered the most cost-effective. Practical biological remediation methods typically involve direct use of the microbes naturally occurring in the contaminated environment and/or cultured indigenous or modified microorganisms. Environmental and nutritional factors, including the properties of the soil, the chemical structure of the hydrocarbon(s), oxygen, water, nutrient availability, pH, temperature, and contaminant bioavailability, can significantly affect the rate and the extent of hydrocarbon biodegradation hydrocarbon biodegradation by microorganisms in contaminated soils. This chapter concisely discusses the major aspects of bioremediation of petroleum contaminants.

Two Catalysts for Selective Oxidation of Contaminant Gases

Science.gov (United States)

Wright, John D.

2011-01-01

Two catalysts for the selective oxidation of trace amounts of contaminant gases in air have been developed for use aboard the International Space Station. These catalysts might also be useful for reducing concentrations of fumes in terrestrial industrial facilities especially facilities that use halocarbons as solvents, refrigerant liquids, and foaming agents, as well as facilities that generate or utilize ammonia. The first catalyst is of the supported-precious-metal type. This catalyst is highly active for the oxidation of halocarbons, hydrocarbons, and oxygenates at low concentrations in air. This catalyst is more active for the oxidation of hydrocarbons and halocarbons than are competing catalysts developed in recent years. This catalyst completely converts these airborne contaminant gases to carbon dioxide, water, and mineral acids that can be easily removed from the air, and does not make any chlorine gas in the process. The catalyst is thermally stable and is not poisoned by chlorine or fluorine atoms produced on its surface during the destruction of a halocarbon. In addition, the catalyst can selectively oxidize ammonia to nitrogen at a temperature between 200 and 260 C, without making nitrogen oxides, which are toxic. The temperature of 260 C is higher than the operational temperature of any other precious-metal catalyst that can selectively oxidize ammonia. The purpose of the platinum in this catalyst is to oxidize hydrocarbons and to ensure that the oxidation of halocarbons goes to completion. However, the platinum exhibits little or no activity for initiating the destruction of halocarbons. Instead, the attack on the halocarbons is initiated by the support. The support also provides a high surface area for exposure of the platinum. Moreover, the support resists deactivation or destruction by halogens released during the destruction of halocarbons. The second catalyst is of the supported- metal-oxide type. This catalyst can selectively oxidize ammonia to

Screening of short- and medium-chain chlorinated paraffins in selected riverine sediments and sludge from the Czech Republic

International Nuclear Information System (INIS)

Pribylova, Petra; Klanova, Jana; Holoubek, Ivan

2006-01-01

Wide distribution of chlorinated paraffins in the environment has already been demonstrated in several studies; however, information about their levels in the Central Europe is still very limited. First study focused on the SCCP contamination of the Czech aquatic environment have been performed recently, and its results motivated the authors to analyze sediments from a wide set of the Czech rivers in order to obtain more detailed information. Thirty-six sediment samples from eleven rivers and five drainage vents neighboring the chemical factories were analyzed; special attention was paid to the industrial areas. For the first time in the Czech Republic, medium-chain in addition to short-chain chlorinated paraffins were analyzed using GC-ECNI-MS. Chlorinated paraffins were detected in sediment samples on the concentration levels up to 347 ng g -1 for short-chain chlorinated paraffins, and 5575 ng g -1 for medium-chain chlorinated paraffins. Average chlorination degree of SCCPs was 65%. - Data on contamination of sediments from industrial areas fill the informational gap in the field of contamination of the Central Europe by chlorinated paraffins

Enhancement and inhibition of microbial activity in hydrocarbon- contaminated arctic soils: Implications for nutrient-amended bioremediation

Science.gov (United States)

Braddock, J.F.; Ruth, M.L.; Catterall, P.H.; Walworth, J.L.; McCarthy, K.A.

1997-01-01

Bioremediation is being used or proposed as a treatment option at many hydrocarbon-contaminated sites. One such site is a former bulk-fuel storage facility near Barrow, AK, where contamination persists after approximately 380 m3 of JP-5 was spilled in 1970. The soil at the site is primarily coarse sand with low organic carbon (soil from this site in laboratory microcosms and in mesocosms incubated for 6 weeks in the field. Nitrogen was the major limiting nutrient in this system, but microbial populations and activity were maximally enhanced by additions of both nitrogen and phosphorus. When nutrients were added to soil in the field at three levels of N:P (100:45, 200:90, and 300:135 mg/kg soil), the greatest stimulation in microbial activity occurred at the lowest, rather than the highest, level of nutrient addition. The total soil-water potentials ranged from -2 to -15 bar with increasing levels of fertilizer. Semivolatile hydrocarbon concentrations declined significantly only in the soils treated at the low fertilizer level. These results indicate that an understanding of nutrient effects at a specific site is essential for successful bioremediation.Bioremediation is being used or proposed as a treatment option at many hydrocarbon-contaminated sites. One such site is a former bulk-fuel storage facility near Barrow, AK, where contamination persists after approximately 380 m3 of JP-5 was spilled in 1970. The soil at the site is primarily coarse sand with low organic carbon (soil from this site in laboratory microcosms and in mesocosms incubated for 6 weeks in the field. Nitrogen was the major limiting nutrient in this system, but microbial populations and activity were maximally enhanced by additions of both nitrogen and phosphorus. When nutrients were added to soil in the field at three levels of N:P (100:45, 200:90, and 300:135 mg/kg soil), the greatest stimulation in microbial activity occurred at the lowest, rather than the highest, level of nutrient addition

Determination of volatile organic hydrocarbons in water samples by solid-phase dynamic extraction

Energy Technology Data Exchange (ETDEWEB)

Jochmann, Maik A.; Schmidt, Torsten C. [Eberhard-Karls-Universitaet Tuebingen, Center for Applied Geoscience (ZAG), Tuebingen (Germany); Chair of Instrumental Analysis, University Duisburg-Essen, Duisburg (Germany); Yuan, Xue [Eberhard-Karls-Universitaet Tuebingen, Center for Applied Geoscience (ZAG), Tuebingen (Germany)

2007-03-15

In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography-mass spectrometry (HS-SPDE-GC/MS) for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated. As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-{mu}m film thickness and 56-mm film length) and were analyzed by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out, extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude. Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally, the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and aromatic hydrocarbons. (orig.)

Determination of volatile organic hydrocarbons in water samples by solid-phase dynamic extraction.

Science.gov (United States)

Jochmann, Maik A; Yuan, Xue; Schmidt, Torsten C

2007-03-01

In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography-mass spectrometry (HS-SPDE-GC/MS) for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated. As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-microm film thickness and 56-mm film length) and were analyzed by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out, extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude. Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally, the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and aromatic hydrocarbons.

Polycyclic aromatic hydrocarbon contamination in stormwater detention pond sediments in coastal South Carolina.

Science.gov (United States)

Weinstein, John E; Crawford, Kevin D; Garner, Thomas R

2010-03-01

The purpose of this study was to characterize the polycyclic aromatic hydrocarbon (PAH) contamination in the sediments of stormwater detention ponds in coastal South Carolina. Levels of the sum of PAH analytes were significantly higher in the sediments of commercial ponds compared to that of reference, golf course, low-density residential, and high-density residential ponds. Isomer ratio analysis suggested that the predominant source of PAHs were pyrogenic; however, many ponds had a PAH signature consistent with mixed uncombusted and combusted PAH sources. PAH levels in these sediments could be modeled using both pond drainage area and pond surface area. These results demonstrate that the sediment from most commercial ponds, and a few residential and golf course ponds, were moderately contaminated with PAHs. PAH levels in these contaminated ponds exceeded between 42% and 75% of the ecological screening values for individual PAH analytes established by US EPA Region IV, suggesting that they may pose a toxicological risk to wildlife.

Enhanced bioremediation of hydrocarbon-contaminated soil using pilot-scale bioelectrochemical systems

International Nuclear Information System (INIS)

Lu, Lu; Yazdi, Hadi; Jin, Song; Zuo, Yi; Fallgren, Paul H.; Ren, Zhiyong Jason

2014-01-01

Highlights: • Pilot bioelectrochemical system showed high-performance hydrocarbon remediation. • Radius of influence characterization demonstrated system efficacy. • Current serves as degradation indicator. - Abstract: Two column-type bioelectrochemical system (BES) modules were installed into a 50-L pilot scale reactor packed with diesel-contaminated soils to investigate the enhancement of passive biodegradation of petroleum compounds. By using low cost electrodes such as biochar and graphite granule as non-exhaustible solid-state electron acceptors, the results show that 82.1–89.7% of the total petroleum hydrocarbon (TPH) was degraded after 120 days across 1–34 cm radius of influence (ROI) from the modules. This represents a maximum of 241% increase of biodegradation compared to a baseline control reactor. The current production in the BESs correlated with the TPH removal, reaching the maximum output of 70.4 ± 0.2 mA/m 2 . The maximum ROI of the BES, deducting influence from the baseline natural attenuation, was estimated to be more than 90 cm beyond the edge of the reactor (34 cm), and exceed 300 cm should a non-degradation baseline be used. The ratio of the projected ROI to the radius of BES (ROB) module was 11–12. The results suggest that this BES can serve as an innovative and sustainable technology for enhanced in situ bioremediation of petroleum hydrocarbons in large field scale, with additional benefits of electricity production and being integrated into existing field infrastructures

Enhanced bioremediation of hydrocarbon-contaminated soil using pilot-scale bioelectrochemical systems

Energy Technology Data Exchange (ETDEWEB)

Lu, Lu; Yazdi, Hadi [Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO (United States); Jin, Song [Department of Civil and Architectural Engineering, University of Wyoming, Laramie, WY (United States); Zuo, Yi [Chevron Energy Technology Company, San Ramon, CA (United States); Fallgren, Paul H. [Department of Civil Engineering, University of Colorado Denver, Denver, CO (United States); Ren, Zhiyong Jason, E-mail: jason.ren@colorado.edu [Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO (United States); Department of Civil Engineering, University of Colorado Denver, Denver, CO (United States)

2014-06-01

Highlights: • Pilot bioelectrochemical system showed high-performance hydrocarbon remediation. • Radius of influence characterization demonstrated system efficacy. • Current serves as degradation indicator. - Abstract: Two column-type bioelectrochemical system (BES) modules were installed into a 50-L pilot scale reactor packed with diesel-contaminated soils to investigate the enhancement of passive biodegradation of petroleum compounds. By using low cost electrodes such as biochar and graphite granule as non-exhaustible solid-state electron acceptors, the results show that 82.1–89.7% of the total petroleum hydrocarbon (TPH) was degraded after 120 days across 1–34 cm radius of influence (ROI) from the modules. This represents a maximum of 241% increase of biodegradation compared to a baseline control reactor. The current production in the BESs correlated with the TPH removal, reaching the maximum output of 70.4 ± 0.2 mA/m{sup 2}. The maximum ROI of the BES, deducting influence from the baseline natural attenuation, was estimated to be more than 90 cm beyond the edge of the reactor (34 cm), and exceed 300 cm should a non-degradation baseline be used. The ratio of the projected ROI to the radius of BES (ROB) module was 11–12. The results suggest that this BES can serve as an innovative and sustainable technology for enhanced in situ bioremediation of petroleum hydrocarbons in large field scale, with additional benefits of electricity production and being integrated into existing field infrastructures.

Contrasting the Community Structure of Arbuscular Mycorrhizal Fungi from Hydrocarbon-Contaminated and Uncontaminated Soils following Willow (Salix spp. L.) Planting

OpenAIRE

Hassan, Saad El-Din; Bell, Terrence H.; Stefani, Franck O. P.; Denis, David; Hijri, Mohamed; St-Arnaud, Marc

2014-01-01

Phytoremediation is a potentially inexpensive alternative to chemical treatment of hydrocarbon-contaminated soils, but its success depends heavily on identifying factors that govern the success of root-associated microorganisms involved in hydrocarbon degradation and plant growth stimulation. Arbuscular mycorrhizal fungi (AMF) form symbioses with many terrestrial plants, and are known to stimulate plant growth, although both species identity and the environment influence this relationship. Al...

Hydrocarbon phytoremediation in the family Fabaceae--a review.

Science.gov (United States)

Hall, Jessica; Soole, Kathleen; Bentham, Richard

2011-04-01

Currently, studies often focus on the use of Poaceae species (grasses) for phytoremediation of hydrocarbon-contaminated soils. Research into the use of Fabaceae species (legumes) to remediate hydrocarbons in soils has been conducted, but these plants are commonly overlooked due to slower recorded rates of degradation compared with many grass species. Evidence in the literature suggests that in some cases Fabaceae species may increase total degradation of hydrocarbons and stimulate degradative capacity of the soil microbial community, particularly for contaminants which are normally more recalcitrant to degradation. As many recalcitrant hydrocarbons have negative impacts on human and ecosystem health, development of remediation options is crucial. Reconsideration of Fabaceae species for removal of such contaminants may lead to environmentally and economically sustainable technologies for remediation of contaminated sites.

Hydrocarbon degraders establish at the costs of microbial richness, abundance and keystone taxa after crude oil contamination in permafrost environments

Science.gov (United States)

Yang, Sizhong; Wen, Xi; Shi, Yulan; Liebner, Susanne; Jin, Huijun; Perfumo, Amedea

2016-01-01

Oil spills from pipeline ruptures are a major source of terrestrial petroleum pollution in cold regions. However, our knowledge of the bacterial response to crude oil contamination in cold regions remains to be further expanded, especially in terms of community shifts and potential development of hydrocarbon degraders. In this study we investigated changes of microbial diversity, population size and keystone taxa in permafrost soils at four different sites along the China-Russia crude oil pipeline prior to and after perturbation with crude oil. We found that crude oil caused a decrease of cell numbers together with a reduction of the species richness and shifts in the dominant phylotypes, while bacterial community diversity was highly site-specific after exposure to crude oil, reflecting different environmental conditions. Keystone taxa that strongly co-occurred were found to form networks based on trophic interactions, that is co-metabolism regarding degradation of hydrocarbons (in contaminated samples) or syntrophic carbon cycling (in uncontaminated samples). With this study we demonstrate that after severe crude oil contamination a rapid establishment of endemic hydrocarbon degrading communities takes place under favorable temperature conditions. Therefore, both endemism and trophic correlations of bacterial degraders need to be considered in order to develop effective cleanup strategies. PMID:27886221

Horizontal arrangement of anodes of microbial fuel cells enhances remediation of petroleum hydrocarbon-contaminated soil.

Science.gov (United States)

Zhang, Yueyong; Wang, Xin; Li, Xiaojing; Cheng, Lijuan; Wan, Lili; Zhou, Qixing

2015-02-01

With the aim of in situ bioremediation of soil contaminated by hydrocarbons, anodes arranged with two different ways (horizontal or vertical) were compared in microbial fuel cells (MFCs). Charge outputs as high as 833 and 762C were achieved in reactors with anodes horizontally arranged (HA) and vertically arranged (VA). Up to 12.5 % of the total petroleum hydrocarbon (TPH) was removed in HA after 135 days, which was 50.6 % higher than that in VA (8.3 %) and 95.3 % higher than that in the disconnected control (6.4 %). Hydrocarbon fingerprint analysis showed that the degradation rates of both alkanes and polycyclic aromatic hydrocarbons (PAHs) in HA were higher than those in VA. Lower mass transport resistance in the HA than that of the VA seems to result in more power and more TPH degradation. Soil pH was increased from 8.26 to 9.12 in HA and from 8.26 to 8.64 in VA, whereas the conductivity was decreased from 1.99 to 1.54 mS/cm in HA and from 1.99 to 1.46 mS/cm in VA accompanied with the removal of TPH. Considering both enhanced biodegradation of hydrocarbon and generation of charge in HA, the MFC with anodes horizontally arranged is a promising configuration for future applications.

Changes in hydrocarbon groups, soil ecotoxicity and microbiology along horizontal and vertical contamination gradients in an old landfarming field for oil refinery waste.

Science.gov (United States)

Mikkonen, Anu; Hakala, Kati P; Lappi, Kaisa; Kondo, Elina; Vaalama, Anu; Suominen, Leena

2012-03-01

Horizontal and vertical contaminant gradients in an old landfarming field for oil refinery waste were characterised with the aim to assess parallel changes in hydrocarbon groups and general, microbiological and ecotoxicological soil characteristics. In the surface soil polar compounds were the most prevalent fraction of heptane-extractable hydrocarbons, superseding GC-FID-resolvable and high-molar-mass aliphatics and aromatics, but there was no indication of their relatively higher mobility or toxicity. The size of the polar fraction correlated poorly with soil physical, chemical and microbiological properties, which were better explained by the total heptane-extractable and total petroleum hydrocarbons (TPH). Deleterious effects on soil microbiology in situ were observed at surprisingly low TPH concentrations (0.3%). Due to the accumulation of polar and complexed degradation products, TPH seems an insufficient measure to assess the quality and monitor the remediation of soil with weathered hydrocarbon contamination. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Feasibility of Tree Coring as a Screening Tool for Selected Contaminants in the Subsurface

DEFF Research Database (Denmark)

Nielsen, Mette Algreen

Chemical release resulting from inadequate care in the handling and storage of compounds has ultimately led to a large number of contaminated sites worldwide. Frequently found contaminants in the terrestrial environment include BTEX (benzene, toluene, ethylbenzene, and xylenes), heavy metals, PAH...... sampling density. This, together with a relatively large soil volume represented by a tree core, has shown to reduce the risk of overlooking contaminated areas and is a valuable method for the identification of previously unknown source areas within a short time period....... (polycyclic aromatic hydrocarbons) and chlorinated solvents. The large number of contaminated sites has created a need for effective and reliable site investigations. In this PhD project the feasibility of tree coring as a screening tool for selected contaminants in the subsurface has been investigated...... to obtain more efficient site investigations. Trees have a natural ability to take up water and nutrients from the subsurface; consequently, contaminants can also enter the roots and be translocated to plant parts above ground where they will be absorbed, degraded or phytovolatilized depending...

Effect of X-ray Contrast Media, Chlorination, and Chloramination on Zebrafish Development

Science.gov (United States)

Effect of X-ray Contrast Media, Chlorination, and Chloramination on Zebrafish Development Little is known about the vertebrate developmental toxicity of chlorinated or chloraminated drinking water (DW), iodinated X-ray contrast media (ICM, a common contaminate of DW) or how the c...

A quantum cascade laser infrared spectrometer for CO2 stable isotope analysis: Field implementation at a hydrocarbon contaminated site under bio-remediation.

Science.gov (United States)

Guimbaud, Christophe; Noel, Cécile; Chartier, Michel; Catoire, Valéry; Blessing, Michaela; Gourry, Jean Christophe; Robert, Claude

2016-02-01

Real-time methods to monitor stable isotope ratios of CO2 are needed to identify biogeochemical origins of CO2 emissions from the soil-air interface. An isotope ratio infra-red spectrometer (IRIS) has been developed to measure CO2 mixing ratio with δ(13)C isotopic signature, in addition to mixing ratios of other greenhouse gases (CH4, N2O). The original aspects of the instrument as well as its precision and accuracy for the determination of the isotopic signature δ(13)C of CO2 are discussed. A first application to biodegradation of hydrocarbons is presented, tested on a hydrocarbon contaminated site under aerobic bio-treatment. CO2 flux measurements using closed chamber method is combined with the determination of the isotopic signature δ(13)C of the CO2 emission to propose a non-intrusive method to monitor in situ biodegradation of hydrocarbons. In the contaminated area, high CO2 emissions have been measured with an isotopic signature δ(13)C suggesting that CO2 comes from petroleum hydrocarbon biodegradation. This first field implementation shows that rapid and accurate measurement of isotopic signature of CO2 emissions is particularly useful in assessing the contribution of contaminant degradation to the measured CO2 efflux and is promising as a monitoring tool for aerobic bio-treatment. Copyright © 2016. Published by Elsevier B.V.

Bacterial community shift and hydrocarbon transformation during bioremediation of short-term petroleum-contaminated soil.

Science.gov (United States)

Wu, Manli; Ye, Xiqiong; Chen, Kaili; Li, Wei; Yuan, Jing; Jiang, Xin

2017-04-01

A laboratory study was conducted to evaluate the impact of bioaugmentation plus biostimulation (BR, added both nutrients and bacterial consortia), and natural attenuation (NA) on hydrocarbon degradation efficiency and microflora characterization during remediation of a freshly contaminated soil. After 112 days of remediation, the initial level of total petroleum hydrocarbon (TPH) (61,000 mg/kg soil) was reduced by 4.5% and 5.0% in the NA and BR treatments, respectively. Bioremediation did not significantly enhance TPH biodegradation compared to natural attenuation. The degradation of the aliphatic fraction was the most active with the degradation rate of 30.3 and 28.7 mg/kg/day by the NA and BR treatments, respectively. Soil microbial activities and counts in soil were generally greater for bioremediation than for natural attenuation. MiSeq sequencing indicated that the diversity and structure of microbial communities were affected greatly by bioremediation. In response to bioremediation treatment, Promicromonospora, Pseudomonas, Microcella, Mycobacterium, Alkanibacter, and Altererythrobacter became dominant genera in the soil. The result indicated that combining bioaugmentation with biostimulation did not improve TPH degradation, but soil microbial activities and structure of microbial communities are sensitive to bioremediation in short-term and heavily oil-contaminated soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

Contamination of ground water, surface water, and soil, and evaluation of selected ground-water pumping alternatives in the Canal Creek area of Aberdeen Proving Ground, Maryland

Science.gov (United States)

Lorah, Michelle M.; Clark, Jeffrey S.

1996-01-01

Chemical manufacturing, munitions filling, and other military-support activities have resulted in the contamination of ground water, surface water, and soil in the Canal Creek area of Aberdeen Proving Ground, Maryland. Chlorinated volatile organic compounds, including 1,1,2,2-tetrachloroethane and trichloroethylene, are widespread ground-water contaminants in two aquifers that are composed of unconsolidated sand and gravel. Distribution and fate of chlorinated organic compounds in the ground water has been affected by the movement and dissolution of solvents in their dense immiscible phase and by microbial degradation under anaerobic conditions. Detection of volatile organic contaminants in adjacent surface water indicates that shallow contaminated ground water discharges to surface water. Semivolatile organic compounds, especially polycyclic aromatic hydrocarbons, are the most prevalent organic contaminants in soils. Various trace elements, such as arsenic, cadmium, lead, and zinc, were found in elevated concentrations in ground water, surface water, and soil. Simulations with a ground-water-flow model and particle tracker postprocessor show that, without remedial pumpage, the contaminants will eventually migrate to Canal Creek and Gunpowder River. Simulations indicate that remedial pumpage of 2.0 million gallons per day from existing wells is needed to capture all particles originating in the contaminant plumes. Simulated pumpage from offsite wells screened in a lower confined aquifer does not affect the flow of contaminated ground water in the Canal Creek area.

Effects of humic acid on phytodegradation of petroleum hydrocarbons in soil simultaneously contaminated with heavy metals

Institute of Scientific and Technical Information of China (English)

Soyoung Park; Ki Seob Kim; Jeong-Tae Kim; Daeseok Kang; Kijune Sung

2011-01-01

The use of humic acid (HA) to enhance the efficiency of phytodegradation of petroleum hydrocarbons in soil contaminated with diesel fuel was evaluated in this study.A sample of soil was artificially contaminated with commercially available diesel fuel to an initial total petroleum hydrocarbons (TPH) concentration of 2300 mg/kg and four heavy metals with concentrations of 400 mg/kg for Pb,200 mg/kg for Cu,12 mg/kg for Cd,and 160 mg/kg for Ni.Three plant species,Brassica campestris,Festuca arundinacea,and Helianthus annuus,were selected for the phytodegradation experiment.Percentage degradation of TPH in the soil in a control pot supplemented with HA increased to 45% from 30% without HA.The addition of HA resulted in an increases in the removal of TPH from the soil in pots planted with B.campestris,F.arundinacea,and H.annuus,enhancing percentage degradation to 86%,64%,and 85% from 45%,54%,and 66%,respectively.The effect of HA was also observed in the degradation of n-alkanes within 30 days.The rates of removal of n-alkanes in soil planted with B.campestris and H.annuus were high for n-alkanes in the range of C11-C28.A dynamic increase in dehydrogenase activity was observed during the last 15 days of a 30-day experimental period in all the pots amended with HA.The enhanced biodegradation performance for TPHs observed might be due to an increase in microbial activities and bioavailable TPH in soils caused by combined effects of plants and HA.The results suggested that HA could act as an enhancing agent for phytodegradation of petroleum hydrocarbons in soil contaminated with diesel fuel and heavy metals.

Technical Protocol for Using Soluble Carbohydrates to Enhance Reductive Dechlorination of Chlorinated Aliphatic Hydrocarbons

Science.gov (United States)

2002-12-19

lead, arsenic, nickel, mercury and cadmium) is also widespread at the same military facilities due to the use of these metals in ordnance...Eds.), Bioremediation and phytoremediation of chlorinated and recalcitrant compounds. Battelle Second International Conference on Remediation of...Electron Donors, in Wickramanayake, G., Gavashkar, A., Alleman, B., Magar, V., eds. Bioremediation and Phytoremediation of Chlorinated and Recalcitrant

Large scale treatment of total petroleum-hydrocarbon contaminated groundwater using bioaugmentation.

Science.gov (United States)

Poi, Gregory; Shahsavari, Esmaeil; Aburto-Medina, Arturo; Mok, Puah Chum; Ball, Andrew S

2018-05-15

Bioaugmentation or the addition of microbes to contaminated sites has been widely used to treat contaminated soil or water; however this approach is often limited to laboratory based studies. In the present study, large scale bioaugmentation has been applied to total petroleum hydrocarbons (TPH)-contaminated groundwater at a petroleum facility. Initial TPH concentrations of 1564 mg L -1 in the field were reduced to 89 mg L -1 over 32 days. This reduction was accompanied by improved ecotoxicity, as shown by Brassica rapa germination numbers that increased from 52 at day 0 to 82% by the end of the treatment. Metagenomic analysis indicated that there was a shift in the microbial community when compared to the beginning of the treatment. The microbial community was dominated by Proteobacteria and Bacteroidetes from day 0 to day 32, although differences at the genus level were observed. The predominant genera at the beginning of the treatment (day 0 just after inoculation) were Cloacibacterium, Sediminibacterium and Brevundimonas while at the end of the treatment members of Flavobacterium dominated, reaching almost half the population (41%), followed by Pseudomonas (6%) and Limnobacter (5.8%). To the author's knowledge, this is among the first studies to report the successful large scale biodegradation of TPH-contaminated groundwater (18,000 L per treatment session) at an offshore petrochemical facility. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterization of hydrocarbon-degrading and biosurfactant-producing Pseudomonas sp. P-1 strain as a potential tool for bioremediation of petroleum-contaminated soil.

Science.gov (United States)

Pacwa-Płociniczak, Magdalena; Płaza, Grażyna Anna; Poliwoda, Anna; Piotrowska-Seget, Zofia

2014-01-01

The Pseudomonas sp. P-1 strain, isolated from heavily petroleum hydrocarbon-contaminated soil, was investigated for its capability to degrade hydrocarbons and produce a biosurfactant. The strain degraded crude oil, fractions A5 and P3 of crude oil, and hexadecane (27, 39, 27 and 13% of hydrocarbons added to culture medium were degraded, respectively) but had no ability to degrade phenanthrene. Additionally, the presence of gene-encoding enzymes responsible for the degradation of alkanes and naphthalene in the genome of the P-1 strain was reported. Positive results of blood agar and methylene blue agar tests, as well as the presence of gene rhl, involved in the biosynthesis of rhamnolipid, confirmed the ability of P-1 for synthesis of glycolipid biosurfactant. 1H and 13C nuclear magnetic resonance, Fourier transform infrared spectrum and mass spectrum analyses indicated that the extracted biosurfactant was affiliated with rhamnolipid. The results of this study indicate that the P-1 and/or biosurfactant produced by this strain have the potential to be used in bioremediation of hydrocarbon-contaminated soils.

Degradation of Total Petroleum Hydrocarbon (TPH) in Contaminated Soil Using Bacillus pumilus MVSV3.

Science.gov (United States)

Varma, Surendra Sheeba; Lakshmi, Mahalingam Brinda; Rajagopal, Perumalsam; Velan, Manickam

2017-01-01

　A study on bioremediation of soil contaminated with petroleum sludge was performed using Bacillus pumilus/MVSV3 (Accession number JN089707). In this study, 5 kg of agricultural soil was mixed well with 5% oil sludge and fertilizers containing nitrogen, phosphorus and potassium (N:P:K). The treatment resulted in 97% removal of total petroleum hydrocarbon (TPH) in 122 d in bacteria mixed contaminated soil when compared to 12% removal of TPH in uninoculated contaminated soil. The population of the microorganism remained stable after introduced into the oil environment. The physical and chemical parameters of the soil mixed with sludge showed variation indicating improvement and the pH level decreased during the experiment period. Elemental analysis and Gas Chromatography-Mass Spectroscopy (GC-MS) analysis revealed the bacterial ability to degrade oil sludge components. Growth experiments with Trigonellafoenumgraecum (Fenugreek) showed the applicability of bioremediated soil for the production.

Phytoremediation of heavy metals and hydrocarbon contaminated soils; Phytoremediation des sols contamines aux metaux lourds et aux hydrocarbures recalcitrants

Energy Technology Data Exchange (ETDEWEB)

Leblanc, R.; Chateauneuf, G.; Sura, C. [Inspec-Sol Inc., Montreal, PQ (Canada); Labrecque, M.; Galipeau, C. [Jardin botanique de Montreal, Montreal, PQ (Canada). Institut de Recherche en Biologie Vegetale; Greer, C.; Delisle, S.; Roy, S.; Labelle, S. [National Research Council of Canada, Montreal, PQ (Canada). Inst. for Research in Biotechnology

2003-07-01

Phytoremediation is a technology that uses plants to decontaminate soils and underground water. Inspec-Sol, a company located in Montreal, Quebec, conducted a two-year study to evaluate the decontamination capabilities of this technology. Trials in greenhouses and field studies at the Pitt Park along the Lachine Canal were conducted. The soils chosen for the studies were soils with concentrations of polycyclic aromatic hydrocarbons (PAH) and heavy metals (lead, copper, zinc) higher than those prescribed for the safe utilization of soils. The trials identified the three plant species (Salix viminalis, Brassica juncea, and Festuca arundinacea) which had the best characteristics for phytoremediation. Controlled experiments were performed to optimize the technology to achieve the maximum extraction of contaminant. It was concluded that phytoremediation has potential for the remediation of urban soils contaminated with organic and inorganic pollutants.

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bailey, V L; McGill, W G [Alberta Univ., Edmonton, AB (Canada). Dept. of Renewable Resources

1999-01-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs.

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bailey, V.L.; McGill, W.G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Renewable Resources

1999-07-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs.

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bailey, V.L.; McGill, W.G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Renewable Resources

1999-09-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs.

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

International Nuclear Information System (INIS)

Bailey, V.L.; McGill, W.G.

1999-01-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs

Volatilisation of aromatic hydrocarbons from soil: part II, fluxes from coal tar contaminated soils residing below the soil surface

International Nuclear Information System (INIS)

Lindhardt, B.; Christensen, T.H.

1996-01-01

The non-steady-state fluxes of aromatic hydrocarbons from coal tar contaminated soil, placed below a 5 cm deep layer of uncontaminated soil, were measured in the laboratory over a period of 53 days. The contaminated soil originated from a former gasworks site and contained concentrations of 11 selected aromatic hydrocarbons between 50 to 840 μg/cm 3 . Where the microbial activity was inhibited, the fluxes stabilized on a semi-steady-state level for the monocyclic aromatic hydrocarbons, naphthalene and 1-methylnaphthalene after a period of 10-20 days. Fluxes of acenaphthene and fluorene were only measurable in an experiment that utilized a cover soil with a low organic content. The fluxes were predicted by a numerical model assuming that the compounds acted independently of each other and that local equilibrium between the air, water, and sorbed phases existed. The model overestimated the fluxes for all the detected aromatic hydrocarbons by a factor of 1.3 to 12. When the cover soil was adapted to degrade naphthalene, the fluxes of naphthalene and 1-methylnaphthalene approached the detection limit after 5 to 8 days. Thereafter the fluxes of these two compounds were less than predicted by the model employing half-life values of 0.5 and 1 day for naphthalene and 1-methylnaphthalene respectively. 10 refs., 6 figs., 7 tabs

Challenges encountered in hydrocarbon contaminated soil cleanup

International Nuclear Information System (INIS)

Lazzarettro, A.C.

1991-01-01

Much of the author's experience relating to the cleanup of hydrocarbon contaminated soils has been garnered from serving the city of Santa Fe Springs, California as a redevelopment consultant and project manager. In this paper, the author's comments will be centered on that community. To set the stage the author believes it might be helpful to relate some of the history and background of Santa Fe Springs (SFS). The community was first founded as an agricultural settlement in the latter part of the nineteenth century, with virtually all of the farms and ranches either planted in orchards or engaged in raising cattle and livestock. The Southern Pacific Railroad had a line running through the area primarily to serve the needs of the ranchers and farmers. The community at the time was known as Fulton Wells in honor of a large hotel complex which had been erected around a well-known mineral spring touted for its curative value. The local population had been aware for some time of the presence of brackish water in shallow wells and of the peculiar odor which permeated much of the surrounding area

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...

Environmental analysis of endocrine disrupting effects from hydrocarbon contaminants in the ecosystem. 1997 annual progress report

International Nuclear Information System (INIS)

1997-01-01

'The overall objective of the basic research grant is to characterize the potential of common hydrocarbon contaminants in ecosystems to act as endocrine disruptors. The three major lines of research include (1) a biotechnology based screening system to identify potential hormone mimics and antagonists; (2) an animal screening system to identify biomarkers of endocrine effects. and (3) a literature review to identify compounds at a variety of DOE sites that need to be examined for endocrine disrupting effects. By relating results obtained from this research project to contamination problems at various DOE sites. CBR will provide data and information on endocrine disrupting contaminants to DOE for consideration in risk analyses for determining clean-up levels and priorities needed at the sites.'

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

Chlorine inactivation of Tubifex tubifex in drinking water and the synergistic effect of sequential inactivation with UV irradiation and chlorine.

Science.gov (United States)

Nie, Xiao-Bao; Li, Zhi-Hong; Long, Yuan-Nan; He, Pan-Pan; Xu, Chao

2017-06-01

The inactivation of Tubifex tubifex is important to prevent contamination of drinking water. Chlorine is a widely-used disinfectant and the key factor in the inactivation of T. tubifex. This study investigated the inactivation kinetics of chlorine on T. tubifex and the synergistic effect of the sequential use of chlorine and UV irradiation. The experimental results indicated that the Ct (concentration × time reaction ) concept could be used to evaluate the inactivation kinetics of T. tubifex with chlorine, thus allowing for the use of a simpler Ct approach for the assessment of T. tubifex chlorine inactivation requirements. The inactivation kinetics of T. tubifex by chlorine was found to be well-fitted to a delayed pseudo first-order Chick-Watson expression. Sequential experiments revealed that UV irradiation and chlorine worked synergistically to effectively inactivate T. tubifex as a result of the decreased activation energy, E a , induced by primary UV irradiation. Furthermore, the inactivation effectiveness of T. tubifex by chlorine was found to be affected by several drinking water quality parameters including pH, turbidity, and chemical oxygen demand with potassium permanganate (COD Mn ) concentration. High pH exhibited pronounced inactivation effectiveness and the decrease in turbidity and COD Mn concentrations contributed to the inactivation of T. tubifex. Copyright © 2017 Elsevier Ltd. All rights reserved.

Environmentally acceptable incineration of chlorinated chemical waste : Review of theory and practice

NARCIS (Netherlands)

De Zeeuw, M.A.; Lemkowitz, S.M.

1987-01-01

Chlorinated hydrocarbons in the form of chemical waste, represent a threat to the environment and public health of the world. Their proper handling, removal and destruction is critical to long term safety. Increasingly strict government legislation is leading to an increase in the quantity of

Heavy metal-immobilizing organoclay facilitates polycyclic aromatic hydrocarbon biodegradation in mixed-contaminated soil

International Nuclear Information System (INIS)

Biswas, Bhabananda; Sarkar, Binoy; Mandal, Asit; Naidu, Ravi

2015-01-01

Highlights: • A novel metal-immobilizing organoclay (MIOC) synthesized and characterized. • MIOC immobilizes toxic metals and reduces metal bioavailability. • It enhances PAH-bioavailability to soil bacteria. • It improves microbial growth and activities in mixed-contaminated soils. • MIOC facilitates PAH-biodegradation in metal co-contaminated soils. - Abstract: Soils contaminated with a mixture of heavy metals and polycyclic aromatic hydrocarbons (PAHs) pose toxic metal stress to native PAH-degrading microorganisms. Adsorbents such as clay and modified clay minerals can bind the metal and reduce its toxicity to microorganisms. However, in a mixed-contaminated soil, an adsorption process more specific to the metals without affecting the bioavailability of PAHs is desired for effective degradation. Furthermore, the adsorbent should enhance the viability of PAH-degrading microorganisms. A metal-immobilizing organoclay (Arquad ® 2HT-75-bentonite treated with palmitic acid) (MIOC) able to reduce metal (cadmium (Cd)) toxicity and enhance PAH (phenanthrene) biodegradation was developed and characterized in this study. The MIOC differed considerably from the parent clay in terms of its ability to reduce metal toxicity (MIOC > unmodified bentonite > Arquad–bentonite). The MIOC variably increased the microbial count (10–43%) as well as activities (respiration 3–44%; enzymatic activities up to 68%), and simultaneously maintained phenanthrene in bioavailable form in a Cd-phenanthrene mixed-contaminated soil over a 21-day incubation period. This study may lead to a new MIOC-assisted bioremediation technique for PAHs in mixed-contaminated soils

Heavy metal-immobilizing organoclay facilitates polycyclic aromatic hydrocarbon biodegradation in mixed-contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Biswas, Bhabananda; Sarkar, Binoy [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, P.O. Box 486, Salisbury, SA 5106 (Australia); Mandal, Asit [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Division of Soil Biology, Indian Institute of Soil Science, Bhopal, Madhya Pradesh (India); Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, P.O. Box 486, Salisbury, SA 5106 (Australia)

2015-11-15

Highlights: • A novel metal-immobilizing organoclay (MIOC) synthesized and characterized. • MIOC immobilizes toxic metals and reduces metal bioavailability. • It enhances PAH-bioavailability to soil bacteria. • It improves microbial growth and activities in mixed-contaminated soils. • MIOC facilitates PAH-biodegradation in metal co-contaminated soils. - Abstract: Soils contaminated with a mixture of heavy metals and polycyclic aromatic hydrocarbons (PAHs) pose toxic metal stress to native PAH-degrading microorganisms. Adsorbents such as clay and modified clay minerals can bind the metal and reduce its toxicity to microorganisms. However, in a mixed-contaminated soil, an adsorption process more specific to the metals without affecting the bioavailability of PAHs is desired for effective degradation. Furthermore, the adsorbent should enhance the viability of PAH-degrading microorganisms. A metal-immobilizing organoclay (Arquad{sup ®} 2HT-75-bentonite treated with palmitic acid) (MIOC) able to reduce metal (cadmium (Cd)) toxicity and enhance PAH (phenanthrene) biodegradation was developed and characterized in this study. The MIOC differed considerably from the parent clay in terms of its ability to reduce metal toxicity (MIOC > unmodified bentonite > Arquad–bentonite). The MIOC variably increased the microbial count (10–43%) as well as activities (respiration 3–44%; enzymatic activities up to 68%), and simultaneously maintained phenanthrene in bioavailable form in a Cd-phenanthrene mixed-contaminated soil over a 21-day incubation period. This study may lead to a new MIOC-assisted bioremediation technique for PAHs in mixed-contaminated soils.

Ex situ treatment of hydrocarbon-contaminated soil using biosurfactants from Lactobacillus pentosus.

Science.gov (United States)

Moldes, Ana Belén; Paradelo, Remigio; Rubinos, David; Devesa-Rey, Rosa; Cruz, José Manuel; Barral, María Teresa

2011-09-14

The utilization of biosurfactants for the bioremediation of contaminated soil is not yet well established, because of the high production cost of biosurfactants. Consequently, it is interesting to look for new biosurfactants that can be produced at a large scale, and it can be employed for the bioremediation of contaminated sites. In this work, biosurfactants from Lactobacillus pentosus growing in hemicellulosic sugars solutions, with a similar composition of sugars found in trimming vine shoot hydrolysates, were employed in the bioremediation of soil contaminated with octane. It was observed that the presence of biosurfactant from L. pentosus accelerated the biodegradation of octane in soil. After 15 days of treatment, biosurfactants from L. pentosus reduced the concentration of octane in the soil to 58.6 and 62.8%, for soil charged with 700 and 70,000 mg/kg of hydrocarbon, respectively, whereas after 30 days of treatment, 76% of octane in soil was biodegraded in both cases. In the absence of biosurfactant and after 15 days of incubation, only 1.2 and 24% of octane was biodegraded in soil charged with 700 and 70,000 mg/kg of octane, respectively. Thus, the use of biosurfactants from L. pentosus, as part of a well-designed bioremediation process, can provide mechanisms to mobilize the target contaminants from the soil surface to make them more available to the microbial population.

Removal of polycyclic aromatic hydrocarbons from aged-contaminated soil using cyclodextrins: Experimental study

International Nuclear Information System (INIS)

Viglianti, Christophe; Hanna, Khalil; Brauer, Christine de; Germain, Patrick

2006-01-01

The removal of polycyclic aromatic hydrocarbons (PAHs) from soil using water as flushing agent is relatively ineffective due to their low aqueous solubility. However, addition of cyclodextrin (CD) in washing solutions has been shown to increase the removal efficiency several times. Herein are investigated the effectiveness of cyclodextrin to remove PAH occurring in industrially aged-contaminated soil. β-Cyclodextrin (BCD), hydroxypropyl-β-cyclodextrin (HPCD) and methyl-β-cyclodextrin (MCD) solutions were used for soil flushing in column test to evaluate some influent parameters that can significantly increase the removal efficiency. The process parameters chosen were CD concentration, ratio of washing solution volume to soil weight, and temperature of washing solution. These parameters were found to have a significant and almost linear effect on PAH removal from the contaminated soil, except the temperature where no significant enhancement in PAH extraction was observed for temperature range from 5 to 35 o C. The PAHs extraction enhancement factor compared to water was about 200. - An innovative method using a biodegradable and non-toxic flushing agent for the depollution of industrially aged-contaminated soil

Visualizing and Quantifying Bioaccessible Pores in Field-Aged Petroleum Hydrocarbon-Contaminated Clay Soils Using Synchrotron-based X-ray Computed Tomography

Science.gov (United States)

Chang, W.; Kim, J.; Zhu, N.; McBeth, J. M.

2015-12-01

Microbial hydrocarbon degradation is environmentally significant and applicable to contaminated site remediation practices only when hydrocarbons (substrates) are physically bioaccessible to bacteria in soil matrices. Powerful X-rays are produced by synchrotron radiation, allowing for bioaccessible pores in soil (larger than 4 microns), where bacteria can be accommodated, colonize and remain active, can be visualized at a much higher resolution. This study visualized and quantified such bioaccessible pores in intact field-aged, oil-contaminated unsaturated soil fractions, and examined the relationship between the abundance of bioaccessible pores and hydrocarbon biodegradation. Using synchrotron-based X-ray Computed Tomography (CT) at the Canadian Light Source, a large dataset of soil particle characteristics, such as pore volumes, surface areas, number of pores and pore size distribution, was generated. Duplicate samples of five different soil fractions with different soil aggregate sizes and water contents (13, 18 and 25%) were examined. The method for calculating the number and distribution of bioaccessible pores using CT images was validated using the known porosity of Ottawa sand. This study indicated that the distribution of bioaccessible pore sizes in soil fractions are very closely related to microbial enhancement. A follow-up aerobic biodegradation experiment for the soils at 17 °C (average site temperature) over 90 days confirmed that a notable decrease in hydrocarbon concentrations occurred in soils fractions with abundant bioaccessible pores and with a larger number of pores between 10 and 100 μm. The hydrocarbon degradation in bioactive soil fractions was extended to relatively high-molecular-weight hydrocarbons (C16-C34). This study provides quantitative information about how internal soil pore characteristics can influence bioremediation performance.

Combining Geoelectrical Measurements and CO2 Analyses to Monitor the Enhanced Bioremediation of Hydrocarbon-Contaminated Soils: A Field Implementation

Directory of Open Access Journals (Sweden)

Cécile Noel

2016-01-01

Full Text Available Hydrocarbon-contaminated aquifers can be successfully remediated through enhanced biodegradation. However, in situ monitoring of the treatment by piezometers is expensive and invasive and might be insufficient as the information provided is restricted to vertical profiles at discrete locations. An alternative method was tested in order to improve the robustness of the monitoring. Geophysical methods, electrical resistivity (ER and induced polarization (IP, were combined with gas analyses, CO2 concentration, and its carbon isotopic ratio, to develop a less invasive methodology for monitoring enhanced biodegradation of hydrocarbons. The field implementation of this monitoring methodology, which lasted from February 2014 until June 2015, was carried out at a BTEX-polluted site under aerobic biotreatment. Geophysical monitoring shows a more conductive and chargeable area which corresponds to the contaminated zone. In this area, high CO2 emissions have been measured with an isotopic signature demonstrating that the main source of CO2 on this site is the biodegradation of hydrocarbon fuels. Besides, the evolution of geochemical and geophysical data over a year seems to show the seasonal variation of bacterial activity. Combining geophysics with gas analyses is thus promising to provide a new methodology for in situ monitoring.

Radiochemical analysis of chlorine-36

International Nuclear Information System (INIS)

Rodriguez, M.; Pina, G.; Lara, E.

2006-01-01

The radioactive chlorine isotope, 36 Cl, decays with a half-life of 3x10 5 years by emitting a beta particle (98 %) and by electron capture. The aim of this paper is to propose a radiochemical separation method of 36 Cl from the other beta-gamma emitters present in low and medium radioactive wastes such as spent ion exchange resins and evaporator concentrates, that arise from Nuclear Power Plants and particularly in the wastes that come from decommissioning activities of graphite reactors, in order to provide data for 36 Cl inventory calculations. The separation method proposed is based on an oxidation technique where chlorine is trapped by NaOH. 36 Cl beta emissions are measured by liquid scintillation counting by the dual label technique in order to avoid the contamination produced by 14 C which is also trapped by NaOH and which is the main contaminant present in graphite samples. The sensitivity of this method is sufficient to achieve the needed thresholds for the radiological characterization of the radioactive materials to which this method can be applied. (author)

Petroleum hydrocarbon biodegradation under seasonal freeze-thaw soil temperature regimes in contaminated soils from a sub-Arctic site.

Science.gov (United States)

Chang, Wonjae; Klemm, Sara; Beaulieu, Chantale; Hawari, Jalal; Whyte, Lyle; Ghoshal, Subhasis

2011-02-01

Several studies have shown that biostimulation in ex situ systems such as landfarms and biopiles can facilitate remediation of petroleum hydrocarbon contaminated soils at sub-Arctic sites during summers when temperatures are above freezing. In this study, we examine the biodegradation of semivolatile (F2: C10-C16) and nonvolatile (F3: C16-C34) petroleum hydrocarbons and microbial respiration and population dynamics at post- and presummer temperatures ranging from -5 to 14 °C. The studies were conducted in pilot-scale tanks with soils obtained from a historically contaminated sub-Arctic site in Resolution Island (RI), Canada. In aerobic, nutrient-amended, unsaturated soils, the F2 hydrocarbons decreased by 32% during the seasonal freeze-thaw phase where soils were cooled from 2 to -5 °C at a freezing rate of -0.12 °C d(-1) and then thawed from -5 to 4 °C at a thawing rate of +0.16 °C d(-1). In the unamended (control) tank, the F2 fraction only decreased by 14% during the same period. Biodegradation of individual hydrocarbon compounds in the nutrient-amended soils was also confirmed by comparing their abundance over time to that of the conserved diesel biomarker, bicyclic sesquiterpanes (BS). During this period, microbial respiration was observed, even at subzero temperatures when unfrozen liquid water was detected during the freeze-thaw period. An increase in culturable heterotrophs and 16S rDNA copy numbers was noted during the freezing phase, and the (14)C-hexadecane mineralization in soil samples obtained from the nutrient-amended tank steadily increased. Hydrocarbon degrading bacterial populations identified as Corynebacterineae- and Alkanindiges-related strains emerged during the freezing and thawing phases, respectively, indicating there were temperature-based microbial community shifts.

Development and field testing of a mobile chlorine dioxide generation system for the decontamination of buildings contaminated with Bacillus anthracis

International Nuclear Information System (INIS)

Wood, Joseph P.; Blair Martin, G.

2009-01-01

The numerous buildings that became contaminated with Bacillus anthracis (the bacterium causing the disease anthrax) in 2001, and more recent B. anthracis - related events, point to the need to have effective decontamination technologies for buildings contaminated with biological threat agents. The U.S. Government developed a portable chlorine dioxide (ClO 2 ) generation system to decontaminate buildings contaminated with B. anthracis spores, and this so-called mobile decontamination trailer (MDT) prototype was tested through a series of three field trials. The first test of the MDT was conducted at Fort McClellan in Anniston, AL. during October 2004. Four test attempts occurred over two weekends; however, a number of system problems resulted in termination of the activity prior to any ClO 2 introduction into the test building. After making several design enhancements and equipment changes, the MDT was subjected to a second test. During this test, extensive leak checks were made using argon and nitrogen in lieu of chlorine gas; each subsystem was checked for functionality, and the MDT was operated for 24 h. This second test demonstrated the MDT flow and control systems functioned satisfactorily, and thus it was decided to proceed to a third, more challenging field trial. In the last field test, ClO 2 was generated and routed directly to the scrubber in a 12-h continuous run. Measurement of ClO 2 levels at the generator outlet showed that the desired production rate was not achieved. Additionally, only one of the two scrubbers performed adequately with regard to maintaining ClO 2 emissions below the limit. Numerous lessons were learned in the field trials of this ClO 2 decontamination technology.

3D electrical image in area contaminated by hydrocarbons at the Cubatao, Brazil, industrial pole; Imageamento eletrico 3D em area contaminada por hidrocarbonetono no polo industrial de Cubatao - SP, Brasil

Energy Technology Data Exchange (ETDEWEB)

Baessa, Marcus Paulus Martins [Centro de Pesquisas e Desenvolvimento Leopoldo Americo Miguez de Mello, CENPES, Rio de Janeiro, RJ (Brazil)], E-mail: marcus.baessa@petrobras.br; Oliva, Andresa; Kiang, Chang Hung [Universidade Estadual Paulista, UNESP, Rio Claro, SP (Brazil)], E-mails: aoliva@rc.unesp.br, chang@rc.unesp.br

2010-12-15

This work presents the results of geophysical surveys performed over an oil contaminated site in the Polo Industrial de Cubatao - Sao Paulo. The aim is to characterize geoelectrical signatures associated to hydrocarbon presence in order to delimit and calculate the volume of the contaminated area. For this study were used Vertical Electrical Sounding (VES) and 3D Electrical Imaging for characterization of geology and geoelectrical response of the contaminant. The results showed that the hydrocarbon presence is associated to conductive anomalies due to products from biodegradation. The conductive anomalies are disseminated over the area, totalizing 1365.3 m3 volume. This volume, however, corresponds only to the residual phase contaminants, since it was not possible to map free-phase hydrocarbons. (author)

Chlorinated polycyclic aromatic hydrocarbons in sediments from industrial areas in Japan and the United States.

Science.gov (United States)

Horii, Yuichi; Ohura, Takeshi; Yamashita, Nobuyoshi; Kannan, Kurunthachalam

2009-11-01

Chlorinated polycyclic aromatic hydrocarbons (ClPAHs) are widespread environmental pollutants in the urban environment. Nevertheless, there is little information available regarding the occurrence and profiles of ClPAHs in environmental matrices. In this study, residual concentrations and profiles of 20 individual ClPAHs and 16 US EPA-priority PAHs were determined using high- resolution gas chromatography-high-resolution mass spectrometry in sediments from water bodies near industrialized areas: Tokyo Bay, Japan; the Saginaw River watershed, Michigan, USA; a former chlor-alkali plant, Georgia, USA; and the New Bedford Harbor Superfund site, Massachusetts, USA. A sediment core from Tokyo Bay showed temporal patterns in the distribution of ClPAHs from the 1950s through 2004. The fluxes of ClPAHs and 16 priority PAHs in Tokyo Bay sediment core were 0.029-0.57 ng/cm(2)/year and 85-609 ng/cm(2)/year, respectively; fluxes were lowest in the 1950s and highest in 1989-1990. In the United States, a high mean concentration of ClPAHs was found in sediment collected near a former chlor-alkali plant [8820 pg/g dry weight (dry wt)], and lower mean concentrations were found for New Bedford Harbor (1880 pg/g dry wt) and the Saginaw River watershed (1140 pg/g dry wt). Among individual ClPAHs, 6-ClBaP and 1-ClPyr were the dominant compounds in sediments; this pattern is similar to the pattern reported in the literature for waste incineration and ambient urban air samples. Significant correlation between SigmaClPAH concentrations and Sigmaparent-PAH concentrations in Tokyo Bay sediment implies that the sources and distribution of ClPAHs are directly related to those of parent PAHs. We also analyzed ClPAHs and parent PAHs in blue mussels from New Bedford Harbor. The mean concentration of ClPAHs in mussels from New Bedford Harbor was 21 ng/g lipid weight, a concentration three orders of magnitude lower than the mean concentration of parent PAHs. Low-molecular-weight ClPAHs predominated

Assessment of organochlorine hydrocarbons transformation in contaminated agricultural products and foodstuffs under gamma-radiation

Science.gov (United States)

Mel'nikova, T. V.; Polyakova, L. P.; Oudalova, A. A.

2017-01-01

The problem of an estimation of organochlorinated pollutants transformation (particularly organochlorinated pesticides (OCP) and polychlorinated biphenyls (PCB)) under gamma-irradiation has become important in connection with radiation technologies application in the food industry. According to earlier researches, small doses of OCP lead to serious damages of an organism, comparable with damages from high doses. Among radiolysis products of OCP in model solutions various substances on a structure have been found out. Though of trace concentration of each of them, in sum with the initial pesticides residue they make up significant of mass contamination (as shown earlier up to 90% from initial OCP). In this work fish samples (bream) containing OCPs (15.20 ng/g of hexachlorocyclohexane isomers and 87.10 ng/g of DDT and its metabolites), as well as PCB (18.51 ng/g) were studied. The minced fish was irradiated at dose of 10 kGy with dose rate of 1.35 Gy/sec. Then, by methods of gas-liquid chromatography (GLC) and gas chromatography-mass spectrometry (GC-MS), it was found that the OCPs degradation varied from 3 up to 61% and the PCB degradation - 24-52%. Significant complication of chemical composition was shown comparing to the primary biological sample contamination. As a result of fish irradiation, secondary pollution appeared that included residues of primary organochlorine hydrocarbons and their radiation-induced metabolites. Among the investigated OCPs the most stable proved to be alfa-hexachlorocyclohexane (alfa-HCH), the least stable - DDT which corresponds to the previous findings about the radiation stability of OCPs in model solutions. Mass spectra of the irradiated samples of minced bream showed the presence of radiation metabolites of OCPs, that had also been found at irradiation of model solutions of 2,2-di(4-chlorophenyl)-1-chlorethylene (DDMU), DDD and 1a, 2e, 3e, 4e, 5e-pentahlorcyclohexane. There was revealed a decomposition product formed during the

Assessment of organochlorine hydrocarbons transformation in contaminated agricultural products and foodstuffs under gamma-radiation

International Nuclear Information System (INIS)

Mel’nikova, T V; Polyakova, L P; Oudalova, A A

2017-01-01

The problem of an estimation of organochlorinated pollutants transformation (particularly organochlorinated pesticides (OCP) and polychlorinated biphenyls (PCB)) under gamma-irradiation has become important in connection with radiation technologies application in the food industry. According to earlier researches, small doses of OCP lead to serious damages of an organism, comparable with damages from high doses. Among radiolysis products of OCP in model solutions various substances on a structure have been found out. Though of trace concentration of each of them, in sum with the initial pesticides residue they make up significant of mass contamination (as shown earlier up to 90% from initial OCP). In this work fish samples (bream) containing OCPs (15.20 ng/g of hexachlorocyclohexane isomers and 87.10 ng/g of DDT and its metabolites), as well as PCB (18.51 ng/g) were studied. The minced fish was irradiated at dose of 10 kGy with dose rate of 1.35 Gy/sec. Then, by methods of gas-liquid chromatography (GLC) and gas chromatography-mass spectrometry (GC-MS), it was found that the OCPs degradation varied from 3 up to 61% and the PCB degradation – 24-52%. Significant complication of chemical composition was shown comparing to the primary biological sample contamination. As a result of fish irradiation, secondary pollution appeared that included residues of primary organochlorine hydrocarbons and their radiation-induced metabolites. Among the investigated OCPs the most stable proved to be alfa-hexachlorocyclohexane (alfa-HCH), the least stable – DDT which corresponds to the previous findings about the radiation stability of OCPs in model solutions. Mass spectra of the irradiated samples of minced bream showed the presence of radiation metabolites of OCPs, that had also been found at irradiation of model solutions of 2,2-di(4-chlorophenyl)-1-chlorethylene (DDMU), DDD and 1a, 2e, 3e, 4e, 5e-pentahlorcyclohexane. There was revealed a decomposition product formed during

Response of core microbial consortia to hydrocarbon contaminations in coastal sediment habitats

Directory of Open Access Journals (Sweden)

Mathilde Jeanbille

2016-10-01

Full Text Available Traditionally, microbial surveys investigating the effect of chronic anthropogenic pressure such as polyaromatic hydrocarbons (PAHs contaminations consider just the alpha and beta diversity and ignore the interactions among the different taxa forming the microbial community. Here, we investigated the ecological relationships between the three domains of life (i.e. Bacteria, Archaea and Eukarya using 454 pyrosequencing data of the 16S rRNA and 18S rRNA genes from chronically impacted and pristine sediments, along the coasts of the Mediterranean Sea (Gulf of Lion, Vermillion coast, Corsica, Bizerte lagoon and Lebanon and the French Atlantic Ocean (Bay of Biscay and English Channel. Our approach provided a robust ecological framework for the partition of the taxa abundance distribution into 859 core OTUs and 6629 satellite OTUs. OTUs forming the core microbial community showed the highest sensitivity to changes in environmental and contaminant variations, with salinity, latitude, temperature, particle size distribution, total organic carbon (TOC and PAH concentrations as main drivers of community assembly. The core communities were dominated by Gammaproteobacteria and Deltaproteobacteria for Bacteria, by Thaumarchaeota, Bathyarchaeota and Thermoplasmata for Archaea and Metazoa and Dinoflagellata for Eukarya. In order to find associations among microorganisms, we generated a co-occurrence network in which PAHs were found to impact significantly the potential predator – prey relationship in one microbial consortium composed of ciliates and Actinobacteria. Comparison of network topological properties between contaminated and non-contaminated samples showed substantial differences in the structure of the network and indicated a higher vulnerability to environmental perturbations in the contaminated sediments.

Bio-remediation of aquifers polluted by chlorinated solvents

International Nuclear Information System (INIS)

Fayolle, F.

1996-01-01

Numerous cases of contamination of aquifers by chlorinated aliphatic solvents, largely utilized during the last decades, constitute a public health problem, because of the toxic effect of such compounds. Different types of aerobic or anaerobic bacteria are able to degrade these molecules. Processes of bio remediation are now experimented in order to restore polluted aquifers. We present here the microorganisms and the enzymatic reactions involved in the biodegradation of chlorinated solvents, and different examples of in situ bio remediation operations are described. (author)

Clonal variation in survival and growth of hybrid poplar and willow in an in situ trial on soils heavily contaminated with petroleum hydrocarbons

Science.gov (United States)

Ronald S., Jr. Zalesny; Edmund O. Bauer; Richard B. Hall; Jill A. Zalesny; Joshua Kunzman; Chris J. Rog; Don E. Riemenschneider

2005-01-01

Species and hybrids between species belonging to the genera Populus (poplar) and Salix (willow) have been used successfully for phytoremediation of contaminated soils. Our objectives were to: 1) evaluate the potential for establishing genotypes of poplar and willow on soils heavily contaminated with petroleum hydrocarbons and 2)...

Reduction of polycyclic aromatic hydrocarbons (PAHs) from petroleum-contaminated soil using thermal desorption technology

International Nuclear Information System (INIS)

Silkebakken, D.M.; Davis, H.A.; Ghosh, S.B.; Beardsley, G.P.

1995-01-01

The remediation of petroleum-contaminated soil typically requires the selection of a treatment option that addresses the removal of both volatile and semi-volatile organic compounds. Volatile organic compounds (VOCs), primarily BTEX (benzene, toluene, ethylbenzene, and xylenes) compounds, can be readily removed from the soil by a variety of well-established technologies. The semivolatile organic compounds, especially the polycyclic aromatic hydrocarbons (PAHS) that are characteristic of petroleum-contaminated soil, are not as amenable to conventional treatment. Low temperature thermal volatilization (LTTV) can be a viable treatment technology depending on the initial contaminant concentrations present and applicable cleanup objectives that must be attained. A-two-phase treatability study was conducted at 14 former underground storage tank (UST) sites to evaluate the applicability and effectiveness of LTTV for remediation of approximately 31,000 tons of PAH-contaminated soil. The PAHs of primary concern included benzo(a)anthracene, chrysene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(g,h,i)perylene, dibenz(a,h) anthracene, and indeno(1,2,3-cd)pyrene. During Phase 1, LTTV operational parameters were varied by trial-and-error and changes in soil treatment effectiveness were monitored. Phase B of the treatability study incorporated the appropriate treatment regime established during Phase 1 to efficiently remediate the remaining contaminated soil

Endophytic root bacteria associated with the natural vegetation growing at the hydrocarbon-contaminated Bitumount Provincial Historic site.

Science.gov (United States)

Blain, Natalie P; Helgason, Bobbi L; Germida, James J

2017-06-01

The Bitumount Provincial Historic site is the location of 2 of the world's first oil-extracting and -refining operations. Despite hydrocarbon levels ranging from 330 to 24 700 mg·(kg soil) -1 , plants have been able to recolonize the site through means of natural revegetation. This study was designed to achieve a better understanding of the plant-root-associated bacterial partnerships occurring within naturally revegetated hydrocarbon-contaminated soils. Root endophytic bacterial communities were characterized from representative plant species throughout the site by both high-throughput sequencing and culturing techniques. Population abundance of rhizosphere and root endosphere bacteria was significantly influenced (p hydrocarbon-degrading genes (CYP153 and alkB) were significantly affected (p < 0.05) by the interaction of plant species and sampling location. Our findings suggest that some of the bacterial communities detected are known to exhibit plant growth promotion characteristics.

Relation between chlorine with the quality of crude water

International Nuclear Information System (INIS)

Lim, Fang Yee; Mohd Pauzi Abdullah

2008-01-01

Chlorine as disinfection agent in drinking water was used widely since it was successfully been practiced in drinking water in Jersey City, 1908. Mostly, water treatment plants in Malaysia were using chlorine as disinfection agent to kill pathogen and contaminated materials that can be dangerous to consumer. Because of chlorine was a strongly disinfection agent, it also can react with another chemical components such as manganese, hydrogen, sulfides, ammonia and phenol in water. These reactions happen very fast, and chlorine will not react as disinfection agent unless all the organic and inorganic substitution presented in water reacts with chlorine. These reactions between components will increase demand of chlorine in water. The demand of chlorine in water must be filled before the free radical chlorine occurred. These free radical chlorine will decay into hypochlorous acid and hypochlorite ion that so important in disinfection process to kill pathogens and pollutants in water. Most of water treatment plant to maintain free chlorine up to 0.2 mg/ L in distribution system to consumer. These researches involved determination of parameters that can be trusted to react with the chlorine in nine sampling station along Semenyih River and four stations in water treatment plants. These parameters were determined from ammonia, cyanides, sulfides, phenol, phosphorus, nitrite, manganese, iron and sum of organic carbons. Overall, these researches concluded that ammonia and sum of organic carbons were the most compounds that react with the chlorine to produce tryhalometane and chloramines. Besides that, the concentration of cyanides compounds, sulfide, phenol, phosphorus, nitrite, manganese and iron also decrease after the chlorination process. Results can used to evaluate demanding levels of chlorine in Semenyih River. (author)

Assessment of intra-species diversity among strains of Acinetobacter baumannii isolated from sites contaminated with petroleum hydrocarbons

International Nuclear Information System (INIS)

Manab Sarma, P.; Bhattacharya, D.; Krishnan, S.; Lal, B.

2004-01-01

Intra-species diversity among Acinetobacter baumannii strains isolated from crude oil-contaminated soils from different geographic regions in India was assessed, including their capability to degrade different fractions of total petroleum hydrocarbons. A total of 96 strains were isolated from five different sites. Of the 96 isolates, 25 strains were identified as Acinetobacter baumannii; all of these strains were biochemically profiled and grouped into eight phenovars on the basis of multivariate analysis of their substrate utilization profiles. All strains were able to degrade the total petroleum hydrocarbon fractions of crude oil. Intraspecies relatedness among the 25 strains was determined using tRNA intergenic spacer length polymorphism. Specific variants among the strains with different degradation capacities for different fractions of crude oil were detected. Environmental influences that cause intra-species diversity, such as functional resilience, within the selected strains of A. baumannii were also noted. It is suggested that such diversities may make it possible to select contaminant-specific strains for efficient biotechnological strategies in environmental remediation. 19 refs., 4 tabs., 3 figs

Assessment of intra-species diversity among strains of Acinetobacter baumannii isolated from sites contaminated with petroleum hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Manab Sarma, P.; Bhattacharya, D.; Krishnan, S. [TERI School of Advanced Studies, Center of Bioresources and Biotechnology, New Delhi (India); Lal, B. [TERI School of Advanced Studies, Microbial Biotechnology Division, New Delhi (India)

2004-06-01

Intra-species diversity among Acinetobacter baumannii strains isolated from crude oil-contaminated soils from different geographic regions in India was assessed, including their capability to degrade different fractions of total petroleum hydrocarbons. A total of 96 strains were isolated from five different sites. Of the 96 isolates, 25 strains were identified as Acinetobacter baumannii; all of these strains were biochemically profiled and grouped into eight phenovars on the basis of multivariate analysis of their substrate utilization profiles. All strains were able to degrade the total petroleum hydrocarbon fractions of crude oil. Intraspecies relatedness among the 25 strains was determined using tRNA intergenic spacer length polymorphism. Specific variants among the strains with different degradation capacities for different fractions of crude oil were detected. Environmental influences that cause intra-species diversity, such as functional resilience, within the selected strains of A. baumannii were also noted. It is suggested that such diversities may make it possible to select contaminant-specific strains for efficient biotechnological strategies in environmental remediation. 19 refs., 4 tabs., 3 figs.

Enumeration of petroleum hydrocarbon utilizing bacteria

International Nuclear Information System (INIS)

Mukherjee, S.; Barot, M.; Levine, A.D.

1996-01-01

In-situ biological treatment is one among a number of emerging technologies that may be applied to the remediation of contaminated soils and groundwater. In 1985, a surface spill of 1,500 gallons of dielectric transformer oil at the Sandia National Laboratories (HERMES II facility) resulted in contamination of soil up to depths of 160 feet. The extent of contamination and site characteristics favored the application of in-situ bioremediation as a potential remedial technology. The purpose of this research was to enumerate indigenous microbial populations capable of degrading petroleum hydrocarbons. Microbial enumeration and characterization methods suitably adapted for hydrocarbon utilizing bacteria were used as an indicator of the presence of viable microbial consortia in excavated oil samples with hydrocarbon (TPH) concentrations ranging from 300 to 26,850 ppm. Microbial activity was quantified by direct and streak plating soil samples on silica gel media. Effects of toxicity and temperature were studied using batch cultures of hydrocarbon utilizing bacteria (selectively isolated in an enrichment medium), at temperatures of 20 and 35 C. It was concluded from this study that it is possible to isolate native microorganisms from contaminated soils from depths of 60 to 160 feet, and with oil concentration ranging from 300 to 26,850 ppm. About 62% of the microorganisms isolated form the contaminated soil were capable of using contaminant oil as a substrate for growth and metabolism under aerobic conditions. Growth rates were observed to be 50% higher for the highest contaminant concentration at 20 C. Resistance to toxicity to contaminant oil was also observed to be greater at 20 C than at 35 C

Application of persulfate to remediate petroleum hydrocarbon-contaminated soil: feasibility and comparison with common oxidants.

Science.gov (United States)

Yen, Chia-Hsien; Chen, Ku-Fan; Kao, Chih-Ming; Liang, Shu-Hao; Chen, Ting-Yu

2011-02-28

In this study, batch experiments were conducted to evaluate the feasibility of petroleum-hydrocarbon contaminated soil remediation using persulfate oxidation. Various controlling factors including different persulfate and ferrous ion concentrations, different oxidants (persulfate, hydrogen peroxide, and permanganate), and different contaminants (diesel and fuel oil) were considered. Results show that persulfate oxidation is capable of treating diesel and fuel oil contaminated soil. Higher persulfate and ferrous ion concentrations resulted in higher diesel degrading rates within the applied persulfate/ferrous ion molar ratios. A two-stage diesel degradation was observed in the batch experiments. In addition, treatment of diesel-contaminated soil using in situ metal mineral activation under ambient temperature (e.g., 25°C) may be a feasible option for site remediation. Results also reveal that persulfate anions could persist in the system for more than five months. Thus, sequential injections of ferrous ion to generate sulfate free radicals might be a feasible way to enhance contaminant oxidation. Diesel oxidation efficiency and rates by the three oxidants followed the sequence of hydrogen peroxide>permanganate>persulfate in the limited timeframes. Results of this study indicate that the application of persulfate oxidation is a feasible method to treat soil contaminated by diesel and fuel oil. Copyright © 2011 Elsevier B.V. All rights reserved.

Bioremediation of petroleum hydrocarbon contaminated soil by Rhodobacter sphaeroides biofertilizer and plants.

Science.gov (United States)

Jiao, Haihua; Luo, Jinxue; Zhang, Yiming; Xu, Shengjun; Bai, Zhihui; Huang, Zhanbin

2015-09-01

Bio-augmentation is a promising technique for remediation of polluted soils. This study aimed to evaluate the bio-augmentation effect of Rhodobacter sphaeroides biofertilizer (RBF) on the bioremediation of total petroleum hydrocarbons (TPH) contaminated soil. A greenhouse pot experiment was conducted over a period of 120 days, three methods for enhancing bio-augmentation were tested on TPH contaminated soils, including single addition RBF, planting, and combining of RBF and three crop species, such as wheat (W), cabbage (C) and spinach (S), respectively. The results demonstrated that the best removal of TPH from contaminated soil in the RBF bio-augmentation rhizosphere soils was found to be 46.2%, 65.4%, 67.5% for W+RBF, C+RBF, S+RBF rhizosphere soils respectively. RBF supply impacted on the microbial community diversity (phospholipid fatty acids, PLFA) and the activity of soil enzymes, such as dehydrogenase (DH), alkaline phosphatase (AP) and urease (UR). There were significant difference among the soil only containing crude oil (CK), W, C and S rhizosphere soils and RBF bio-augmentation soils. Moreover, the changes were significantly distinct depended on crops species. It was concluded that the RBF is a valuable material for improving effect of remediation of TPH polluted soils.

Chlorinated pesticide residues in sediments from the Arabian Sea along the Central West coast of India

Digital Repository Service at National Institute of Oceanography (India)

Sarkar, A.; SenGupta, R.

Environmental contamination by persistent chlorinated pesticides has evoked major concern due to the presence of their residues in the environment. The quantitative distribution of chlorinated pesticides residues in the marine sediments from...

Long-term ERT monitoring of biogeochemical changes of an aged hydrocarbon contamination

Science.gov (United States)

Caterina, David; Flores Orozco, Adrian; Nguyen, Frédéric

2017-06-01

Adequate management of contaminated sites requires information with improved spatio-temporal resolution, in particular to assess bio-geochemical processes, such as the transformation and degradation of contaminants, precipitation of minerals or changes in groundwater geochemistry occurring during and after remediation procedures. Electrical Resistivity Tomography (ERT), a geophysical method sensitive to pore-fluid and pore-geometry properties, permits to gain quasi-continuous information about subsurface properties in real-time and has been consequently widely used for the characterization of hydrocarbon-impacted sediments. However, its application for the long-term monitoring of processes accompanying natural or engineered bioremediation is still difficult due to the poor understanding of the role that biogeochemical processes play in the electrical signatures. For in-situ studies, the task is further complicated by the variable signal-to-noise ratio and the variations of environmental parameters leading to resolution changes in the electrical images. In this work, we present ERT imaging results for data collected over a period of two years on a site affected by a diesel fuel contamination and undergoing bioremediation. We report low electrical resistivity anomalies in areas associated to the highest contaminant concentrations likely due transformations of the contaminant due to microbial activity and accompanying release of metabolic products. We also report large seasonal variations of the bulk electrical resistivity in the contaminated areas in correlation with temperature and groundwater level fluctuations. However, the amplitude of bulk electrical resistivity variations largely exceeds the amplitude expected given existing petrophysical models. Our results suggest that the variations in electrical properties are mainly controlled by microbial activity which in turn depends on soil temperature and hydrogeological conditions. Therefore, ERT can be suggested as

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.

Microbial metabolism and community structure in response to bioelectrochemically enhanced remediation of petroleum hydrocarbon-contaminated soil.

Science.gov (United States)

Lu, Lu; Huggins, Tyler; Jin, Song; Zuo, Yi; Ren, Zhiyong Jason

2014-04-01

This study demonstrates that electrodes in a bioelectrochemical system (BES) can potentially serve as a nonexhaustible electron acceptor for in situ bioremediation of hydrocarbon contaminated soil. The deployment of BES not only eliminates aeration or supplement of electron acceptors as in contemporary bioremediation but also significantly shortens the remediation period and produces sustainable electricity. More interestingly, the study reveals that microbial metabolism and community structure distinctively respond to the bioelectrochemically enhanced remediation. Tubular BESs with carbon cloth anode (CCA) or biochar anode (BCA) were inserted into raw water saturated soils containing petroleum hydrocarbons for enhancing in situ remediation. Results show that total petroleum hydrocarbon (TPH) removal rate almost doubled in soils close to the anode (63.5-78.7%) than that in the open circuit positive controls (37.6-43.4%) during a period of 64 days. The maximum current density from the BESs ranged from 73 to 86 mA/m(2). Comprehensive microbial and chemical characterizations and statistical analyses show that the residual TPH has a strongly positive correlation with hydrocarbon-degrading microorganisms (HDM) numbers, dehydrogenase activity, and lipase activity and a negative correlation with soil pH, conductivity, and catalase activity. Distinctive microbial communities were identified at the anode, in soil with electrodes, and soil without electrodes. Uncommon electrochemically active bacteria capable of hydrocarbon degradation such as Comamonas testosteroni, Pseudomonas putida, and Ochrobactrum anthropi were selectively enriched on the anode, while hydrocarbon oxidizing bacteria were dominant in soil samples. Results from genus or phylum level characterizations well agree with the data from cluster analysis. Data from this study suggests that a unique constitution of microbial communities may play a key role in BES enhancement of petroleum hydrocarbons

Bioremediation of chlorinated ethenes in aquifer thermal energy storage

NARCIS (Netherlands)

Ni, Z.

2015-01-01

Subjects: bioremediation; biodegradation; environmental biotechnology, subsurface and groundwater contamination; biological processes; geochemistry; microbiology

The combination of enhanced natural attenuation (ENA) of chlorinated volatile organic compounds

Using the nuclear activation AMS method for determining chlorine in solids at ppb-levels and below

International Nuclear Information System (INIS)

Winkler, Stephan R.; Eigl, Rosmarie; Forstner, Oliver; Martschini, Martin; Steier, Peter; Sterba, Johannes H.; Golser, Robin

2015-01-01

Neutron activation analysis using decay counting of the activated element is a well-established method in elemental analysis. However, for chlorine there is a better alternative to measuring decay of the short-lived activation product chlorine-38 (t 1/2 = 37.24 min) – accelerator mass spectrometry (AMS) of 36 Cl: the relatively high neutron capture cross section of chlorine-35 for thermal neutrons (43.7 b) and combined the AMS technique for chlorine-36 (t 1/2 = 301 ka) allow for determination of chlorine down to ppb-levels using practical sample sizes and common exposure durations. The combination of neutron activation and AMS can be employed for a few other elements (nitrogen, thorium, and uranium) as well. For bulk solid samples an advantage of the method is that lab contamination can be rendered irrelevant. The chlorine-35 in the sample is activated to chlorine-36, and surface chlorine can be removed after the irradiation. Subsequent laboratory contamination, however, will not carry a prominent chlorine-36 signature. After sample dissolution and addition of sufficient amounts of stable chlorine carrier the produced chlorine-36 and thus the original chlorine-35 of the sample can be determined using AMS. We have developed and applied the method for analysis of chlorine in steel samples. The chlorine content of steel is of interest to nuclear industry, precisely because of above mentioned high neutron capture cross section for chlorine-35, which leads to accumulation of chlorine-36 as long-term nuclear waste. The samples were irradiated at the TRIGA Mark II reactor of the Atominstitut in Vienna and the 36 Cl-AMS setup at the Vienna Environmental Research Accelerator (VERA) was used for 36 Cl/Cl analysis.

Using the nuclear activation AMS method for determining chlorine in solids at ppb-levels and below

Energy Technology Data Exchange (ETDEWEB)

Winkler, Stephan R., E-mail: srw@tlabs.ac.za [Universität Wien, Fakultät für Physik, Institut für Isotopenforschung und Kernphysik (Austria); Eigl, Rosmarie [Universität Wien, Fakultät für Chemie, Institut für Anorganische Chemie (Austria); Forstner, Oliver; Martschini, Martin; Steier, Peter [Universität Wien, Fakultät für Physik, Institut für Isotopenforschung und Kernphysik (Austria); Sterba, Johannes H. [Technische Universität Wien, Atominstitut (Austria); Golser, Robin [Universität Wien, Fakultät für Physik, Institut für Isotopenforschung und Kernphysik (Austria)

2015-10-15

Neutron activation analysis using decay counting of the activated element is a well-established method in elemental analysis. However, for chlorine there is a better alternative to measuring decay of the short-lived activation product chlorine-38 (t{sub 1/2} = 37.24 min) – accelerator mass spectrometry (AMS) of {sup 36}Cl: the relatively high neutron capture cross section of chlorine-35 for thermal neutrons (43.7 b) and combined the AMS technique for chlorine-36 (t{sub 1/2} = 301 ka) allow for determination of chlorine down to ppb-levels using practical sample sizes and common exposure durations. The combination of neutron activation and AMS can be employed for a few other elements (nitrogen, thorium, and uranium) as well. For bulk solid samples an advantage of the method is that lab contamination can be rendered irrelevant. The chlorine-35 in the sample is activated to chlorine-36, and surface chlorine can be removed after the irradiation. Subsequent laboratory contamination, however, will not carry a prominent chlorine-36 signature. After sample dissolution and addition of sufficient amounts of stable chlorine carrier the produced chlorine-36 and thus the original chlorine-35 of the sample can be determined using AMS. We have developed and applied the method for analysis of chlorine in steel samples. The chlorine content of steel is of interest to nuclear industry, precisely because of above mentioned high neutron capture cross section for chlorine-35, which leads to accumulation of chlorine-36 as long-term nuclear waste. The samples were irradiated at the TRIGA Mark II reactor of the Atominstitut in Vienna and the {sup 36}Cl-AMS setup at the Vienna Environmental Research Accelerator (VERA) was used for {sup 36}Cl/Cl analysis.

Using the nuclear activation AMS method for determining chlorine in solids at ppb-levels and below

Science.gov (United States)

Winkler, Stephan R.; Eigl, Rosmarie; Forstner, Oliver; Martschini, Martin; Steier, Peter; Sterba, Johannes H.; Golser, Robin

2015-10-01

Neutron activation analysis using decay counting of the activated element is a well-established method in elemental analysis. However, for chlorine there is a better alternative to measuring decay of the short-lived activation product chlorine-38 (t1/2 = 37.24 min) - accelerator mass spectrometry (AMS) of 36Cl: the relatively high neutron capture cross section of chlorine-35 for thermal neutrons (43.7 b) and combined the AMS technique for chlorine-36 (t1/2 = 301 ka) allow for determination of chlorine down to ppb-levels using practical sample sizes and common exposure durations. The combination of neutron activation and AMS can be employed for a few other elements (nitrogen, thorium, and uranium) as well. For bulk solid samples an advantage of the method is that lab contamination can be rendered irrelevant. The chlorine-35 in the sample is activated to chlorine-36, and surface chlorine can be removed after the irradiation. Subsequent laboratory contamination, however, will not carry a prominent chlorine-36 signature. After sample dissolution and addition of sufficient amounts of stable chlorine carrier the produced chlorine-36 and thus the original chlorine-35 of the sample can be determined using AMS. We have developed and applied the method for analysis of chlorine in steel samples. The chlorine content of steel is of interest to nuclear industry, precisely because of above mentioned high neutron capture cross section for chlorine-35, which leads to accumulation of chlorine-36 as long-term nuclear waste. The samples were irradiated at the TRIGA Mark II reactor of the Atominstitut in Vienna and the 36Cl-AMS setup at the Vienna Environmental Research Accelerator (VERA) was used for 36Cl/Cl analysis.

In-situ treatment of a mixed hydrocarbon plume through enhanced bio-remediation and a PRB system

International Nuclear Information System (INIS)

Aglietto, I.; Bargoni, G.; Bretti, L.L.

2005-01-01

Groundwater is frequently polluted with mixtures of contaminants that are amenable to different types of remediation. One example is the combination of petroleum hydrocarbons (BTEX) and chlorinated solvents (PCE, TCE, DCE, VC), as it occurs in the groundwater beneath the industrial site that is the objective of the present case study. The site is located in Italy near a main river (Arno), which is supposed to be the final recipient of the contamination and where a possible exposure might take place. The aim of the treatment is the plume containment within the site boundaries in order to avoid further migration of the contaminants towards the river. The design of the remediation system was based on an extensive site characterization that included - but was not limited to - the following information: geological and geochemical, microbiological and hydrological data, together with analytical data (i.e. contaminant concentrations). Pilot tests were also implemented in order to collect the necessary parameters for the full-scale treatment design and calibration. The monitoring of the site conditions was carried out throughout a period of several months, both with periodical measurements and sampling and with fixed monitoring probes, in order to record the aquifer changes (levels, concentrations, etc.) related both to seasonal variations and to the pilot tests. The groundwater is located in a highly heterogeneous aquifer, with a saturated thickness of 1.5 m and an average hydraulic conductivity of 2.5 x 10 -5 m/s. The seepage velocity is extremely low, with a mean value around 1.3 mm/d. This results in a long residence time and limited volumes per time unit to be treated. The site was contaminated by a mixed plume of more than 15 different contaminants, ranging from BTEX, to MTBE, to PAH, to chlorinated solvents. The concentration peaks were in the order of 1-100 mg/l for each contaminant. Petroleum hydrocarbons are quickly degradable through oxidative mechanisms

In-situ treatment of a mixed hydrocarbon plume through enhanced bio-remediation and a PRB system

Energy Technology Data Exchange (ETDEWEB)

Aglietto, I.; Bargoni, G.; Bretti, L.L. [Studio aglietto s.r.l. (Italy)

2005-07-01

Groundwater is frequently polluted with mixtures of contaminants that are amenable to different types of remediation. One example is the combination of petroleum hydrocarbons (BTEX) and chlorinated solvents (PCE, TCE, DCE, VC), as it occurs in the groundwater beneath the industrial site that is the objective of the present case study. The site is located in Italy near a main river (Arno), which is supposed to be the final recipient of the contamination and where a possible exposure might take place. The aim of the treatment is the plume containment within the site boundaries in order to avoid further migration of the contaminants towards the river. The design of the remediation system was based on an extensive site characterization that included - but was not limited to - the following information: geological and geochemical, microbiological and hydrological data, together with analytical data (i.e. contaminant concentrations). Pilot tests were also implemented in order to collect the necessary parameters for the full-scale treatment design and calibration. The monitoring of the site conditions was carried out throughout a period of several months, both with periodical measurements and sampling and with fixed monitoring probes, in order to record the aquifer changes (levels, concentrations, etc.) related both to seasonal variations and to the pilot tests. The groundwater is located in a highly heterogeneous aquifer, with a saturated thickness of 1.5 m and an average hydraulic conductivity of 2.5 x 10{sup -5} m/s. The seepage velocity is extremely low, with a mean value around 1.3 mm/d. This results in a long residence time and limited volumes per time unit to be treated. The site was contaminated by a mixed plume of more than 15 different contaminants, ranging from BTEX, to MTBE, to PAH, to chlorinated solvents. The concentration peaks were in the order of 1-100 mg/l for each contaminant. Petroleum hydrocarbons are quickly degradable through oxidative mechanisms

Field—Based Supercritical Fluid Extraction of Hydrocarbons at Industrially Contaminated Sites

Directory of Open Access Journals (Sweden)

Peggy Rigou

2002-01-01

Full Text Available Examination of organic pollutants in groundwaters should also consider the source of the pollution, which is often a solid matrix such as soil, landfill waste, or sediment. This premise should be viewed alongside the growing trend towards field-based characterisation of contaminated sites for reasons of speed and cost. Field-based methods for the extraction of organic compounds from solid samples are generally cumbersome, time consuming, or inefficient. This paper describes the development of a field-based supercritical fluid extraction (SFE system for the recovery of organic contaminants (benzene, toluene, ethylbenzene, and xylene and polynuclear aromatic hydrocarbons from soils. A simple, compact, and robust SFE system has been constructed and was found to offer the same extraction efficiency as a well-established laboratory SFE system. Extraction optimisation was statistically evaluated using a factorial analysis procedure. Under optimised conditions, the device yielded recovery efficiencies of >70% with RSD values of 4% against the standard EPA Soxhlet method, compared with a mean recovery efficiency of 48% for a commercially available field-extraction kit. The device will next be evaluated with real samples prior to field deployment.

Management of hydrocarbon-contaminated soil through bioremediation and landfill disposal at a remote location in northern Canada

Energy Technology Data Exchange (ETDEWEB)

Sanscartier, D.; Reimer, K.; Zeeb, B.; George, K. [Royal Military Coll. of Canada, Kingston, ON (Canada). Environmental Sciences Group; Royal Military Coll. of Canada, Kingston, ON (Canada). Dept. of Chemistry and Chemical Engineering

2010-01-15

This paper described an innovative method of managing diesel-contaminated soil in a remote Labrador community. The soil was treated in an aerated biopile to reduce mobile petroleum hydrocarbons (PHC) concentrations. The soil was then disposed of in a local landfill. An analysis of the soils showed that the method reduced total petroleum hydrocarbon (TPH) concentrations in the soil. Hydrocarbon concentrations were measured using the Canada-Wide standard reference method. TPH in leachate decreased during the 1-year field treatment period. PHC fractions were reduced to below the standard criteria for the protection of aquatic life. Volatilization was the predominant PHC removal mechanism in the field. The treated soils were used as a landfill cover for refuse. The cost of the treatment method compared favorably with other land remediation techniques. The biopile facility will be used to treat other fuel spills in the community and serve as a demonstration project for other communities. 36 refs., 4 tabs., 3 figs.

Soil-Water Repellency and Critical Humidity as Cleanup Criteria for Remediation of a Hydrocarbon Contaminated Mud

Science.gov (United States)

Guzmán, Francisco Javier; Adams, Randy H.

2010-05-01

The majority of soil remediation programs focus mainly on reducing the hydrocarbon concentration, based on the assumption that the primary impact is toxicity and/or leachates and that these are directly proportional to concentration. None-the-less, interference with natural soil-water interactions are frequently more damaging, especially for sites contaminated with very viscous, weathered hydrocarbons. Therefore, the kind of hydrocarbons present in the soil and their interactions with soil surfaces may be more important than the overall hydrocarbon concentration in terms of soil restoration. One recently patented technology, the Chemical-Biological Stabilization process, focuses specifically on restoring soil fertility as the main objective for remediation of sites with agricultural use. This method was recently validated at an industrial scale by the treatment of 150 cubic meters of bentonitic drilling muds (70,5% fines) from an old sulphur mine, which were contaminated with very weathered oil (4° API), consisting of 31% asphaltenes. This material was treated by adding 4% (w/w, dry) of calcium hydroxide, followed by 4% (w/w, dry) of sugar cane cachasse (a fine fibered agricultural waste), thoroughly mixing between additions using an excavator. After the soil had dried sufficiently and the pH was soil water repellency. MED was measured on air dried soil and WDPT values were calculated from the extrapolation of penetration time vs. ethanol molarity functions (Rx=0,99). Additionally, water penetration times were measured at different humidities to determine critical moisture levels for absorption in soil humic substances while a vigorous vegetative growth was established. During two years of treatment the MED values were reduced 30% from 5,13 to 3,58M, and WDPT values were reduced over 25 times (from 10 exp5,6 s to 10 exp4,2 s). Critical humidity values varied from ~16,9 - 19,5%H for penetration in treated and untreated material. During the driest part of the year

Enhanced salmonella reduction on tomatoes washed in chlorinated water with wash aid T-128

Science.gov (United States)

Chlorine is widely used by the fresh and fresh-cut produce industries to reduce microbial populations and to prevent potential pathogen cross contamination during produce washing. However, the organic materials released from produce quickly react with chlorine and degrade its efficacy for pathogen i...

Estimating release of polycyclic aromatic hydrocarbons from coal-tar contaminated soil at manufactured gas plant sites. Final report

International Nuclear Information System (INIS)

Lee, L.S.

1998-04-01

One of EPRI's goals regarding the environmental behavior of organic substances consists of developing information and predictive tools to estimate the release potential of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils at manufactured gas (MGP) plant sites. A proper assessment of the distribution of contaminants under equilibrium conditions and the potential for mass-transfer constraints is essential in evaluating the environmental risks of contaminants in the subsurface at MGP sites and for selecting remediation options. The results of this research provide insights into estimating maximum release concentrations of PAHs from MGP soils that have been contaminated by direct contact with the tar or through years of contact with contaminated groundwater. Attention is also given to evaluating the use of water-miscible cosolvents for estimating aqueous phase concentrations, and assessing the role of mass-transfer constraints in the release of PAHs from MGP site soils

Simultaneous determination of polycyclic aromatic hydrocarbons and their chlorination by-products in drinking water and the coatings of water pipes by automated solid-phase microextraction followed by gas chromatography-mass spectrometry.

Science.gov (United States)

Tillner, Jocelyn; Hollard, Caroline; Bach, Cristina; Rosin, Christophe; Munoz, Jean-François; Dauchy, Xavier

2013-11-08

In this study, an automated method for the simultaneous determination of polycyclic aromatic hydrocarbons (PAHs) and their chlorination by-products in drinking water was developed based on online solid-phase microextraction-gas chromatography-mass spectrometry. The main focus was the optimisation of the solid-phase microextraction step. The influence of the agitation rate, type of fibre, desorption time, extraction time, extraction temperature, desorption temperature, and solvent addition was examined. The method was developed and validated using a mixture of 17 PAHs, 11 potential chlorination by-products (chlorinated and oxidised PAHs) and 6 deuterated standards. The limit of quantification was 10 ng/L for all target compounds. The validated method was used to analyse drinking water samples from three different drinking water distribution networks and the presumably coal tar-based pipe coatings of two pipe sections. A number of PAHs were detected in all three networks although individual compositions varied. Several PAH chlorination by-products (anthraquinone, fluorenone, cyclopenta[d,e,f]phenanthrenone, 3-chlorofluoranthene, and 1-chloropyrene) were also found, their presence correlating closely with that of their respective parent compounds. Their concentrations were always below 100 ng/L. In the coatings, all PAHs targeted were detected although concentrations varied between the two coatings (76-12,635 mg/kg and 12-6295 mg/kg, respectively). A number of chlorination by-products (anthraquinone, fluorenone, cyclopenta[d,e,f]phenanthrenone, 3-chlorofluoranthene, and 1-chloropyrene) were also detected (from 40 to 985 mg/kg), suggesting that the reaction of PAHs with disinfectant agents takes place in the coatings and not in the water phase after migration. Copyright © 2013 Elsevier B.V. All rights reserved.

Chlorinated hydrocarbon pesticides and polychlorinated biphenyls in sediment cores from San Francisco Bay

Science.gov (United States)

Venkatesan, M.I.; De Leon, R. P.; VanGeen, A.; Luoma, S.N.

1999-01-01

Sediment cores of known chronology from Richardson and San Pablo Bays in San Francisco Bay, CA, were analyzed for a suite of chlorinated hydrocarbon pesticides and polychlorinated biphenyls to reconstruct a historic record of inputs. Total DDTs (DDT = 2,4'- and 4,4'-dichlorodiphenyltrichloroethane and the metabolites, 2,4'- and 4,4'-DDE, -DDD) range in concentration from 4-21 ng/g and constitute a major fraction (> 84%) of the total pesticides in the top 70 cm of Richardson Bay sediment. A subsurface maximum corresponds to a peak deposition date of 1969-1974. The first measurable DDT levels are found in sediment deposited in the late 1930's. The higher DDT inventory in the San Pablo relative to the Richardson Bay core probably reflects the greater proximity of San Pablo Bay to agricultural activities in the watershed of the Sacramento and San Joaquin rivers. Total polychlorinated biphenyls (PCBs) occur at comparable levels in the two Bays (inventories in San Pablo Bay are about a factor of four higher in the last four decades than in Richardson Bay, suggesting a distribution of inputs not as strongly weighed towards the upper reaches of the estuary as DDTs. The shallower subsurface maximum in PCBs compared to DDT in the San Pablo Bay core is consistent with the imposition of drastic source control measures four these constituents in 1970 and 1977 respectively. The observed decline in DDT and PCB levels towards the surface of both cores is consistent with a dramatic drop in the input of these pollutants once the effect of sediment resuspension and mixing is taken into account.

Combination of surfactant enhanced soil washing and electro-Fenton process for the treatment of soils contaminated by petroleum hydrocarbons.

Science.gov (United States)

Huguenot, David; Mousset, Emmanuel; van Hullebusch, Eric D; Oturan, Mehmet A

2015-04-15

In order to improve the efficiency of soil washing treatment of hydrocarbon contaminated soils, an innovative combination of this soil treatment technique with an electrochemical advanced oxidation process (i.e. electro-Fenton (EF)) has been proposed. An ex situ soil column washing experiment was performed on a genuinely diesel-contaminated soil. The washing solution was enriched with surfactant Tween 80 at different concentrations, higher than the critical micellar concentration (CMC). The impact of soil washing was evaluated on the hydrocarbons concentration in the leachates collected at the bottom of the soil columns. These eluates were then studied for their degradation potential by EF treatment. Results showed that a concentration of 5% of Tween 80 was required to enhance hydrocarbons extraction from the soil. Even with this Tween 80 concentration, the efficiency of the treatment remained very low (only 1% after 24 h of washing). Electrochemical treatments performed thereafter with EF on the collected eluates revealed that the quasi-complete mineralization (>99.5%) of the hydrocarbons was achieved within 32 h according to a linear kinetic trend. Toxicity was higher than in the initial solution and reached 95% of inhibition of Vibrio fischeri bacteria measured by Microtox method, demonstrating the presence of remaining toxic compounds even after the complete degradation. Finally, the biodegradability (BOD₅/COD ratio) reached a maximum of 20% after 20 h of EF treatment, which is not enough to implement a combined treatment with a biological treatment process. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hydrogeologic characterization and assessment of bioremediation of chlorinated benzenes and benzene in wetland areas, Standard Chlorine of Delaware, Inc. Superfund Site, New Castle County, Delaware, 2009-12

Science.gov (United States)

Lorah, Michelle M.; Walker, Charles W.; Baker, Anna C.; Teunis, Jessica A.; Emily Majcher,; Brayton, Michael J.; Raffensperger, Jeff P.; Cozzarelli, Isabelle M.

2015-01-01

Wetlands at the Standard Chlorine of Delaware, Inc. Superfund Site (SCD) in New Castle County, Delaware, are affected by contamination with chlorobenzenes and benzene from past waste storage and disposal, spills, leaks, and contaminated groundwater discharge. In cooperation with the U.S. Environmental Protection Agency, the U.S. Geological Survey began an investigation in June 2009 to characterize the hydrogeology and geochemistry in the wetlands and assess the feasibility of monitored natural attenuation and enhanced bioremediation as remedial strategies. Groundwater flow in the wetland study area is predominantly vertically upward in the wetland sediments and the underlying aquifer, and groundwater discharge accounts for a minimum of 47 percent of the total discharge for the subwatershed of tidal Red Lion Creek. Thus, groundwater transport of contaminants to surface water could be significant. The major contaminants detected in groundwater in the wetland study area included benzene, monochlorobenzene, and tri- and di-chlorobenzenes. Shallow wetland groundwater in the northwest part of the wetland study area was characterized by high concentrations of total chlorinated benzenes and benzene (maximum about 75,000 micrograms per liter [μg/L]), low pH, and high chloride. In the northeast part of the wetland study area, wetland groundwater had low to moderate concentrations of total chlorinated benzenes and benzene (generally not greater than 10,000 μg/L), moderate pH, and high sulfate concentrations. Concentrations in the groundwater in excess of 1 percent of the solubility of the individual chlorinated benzenes indicate that a contaminant source is present in the wetland sediments as dense nonaqueous phase liquids (DNAPLs). Consistently higher contaminant concentrations in the shallow wetland groundwater than deeper in the wetland sediments or the aquifer also indicate a continued source in the wetland sediments, which could include dissolution of DNAPLs and

Chlorine-rich plasma polymer coating for the prevention of attachment of pathogenic fungal cells onto materials surfaces

International Nuclear Information System (INIS)

Lamont-Friedrich, Stephanie J; Michl, Thomas D; Giles, Carla; Griesser, Hans J; Coad, Bryan R

2016-01-01

The attachment of pathogenic fungal cells onto materials surfaces, which is often followed by biofilm formation, causes adverse consequences in a wide range of areas. Here we have investigated the ability of thin film coatings from chlorinated molecules to deter fungal colonization of solid materials by contact killing of fungal cells reaching the surface of the coating. Coatings were deposited onto various substrate materials via plasma polymerization, which is a substrate-independent process widely used for industrial coating applications, using 1,1,2-trichloroethane as the process vapour. XPS surface analysis showed that the coatings were characterized by a highly chlorinated hydrocarbon polymer nature, with only a very small amount of oxygen incorporated. The activity of these coatings against human fungal pathogens was quantified using a recently developed, modified yeast assay and excellent antifungal activity was observed against Candida albicans and Candida glabrata . Plasma polymer surface coatings derived from chlorinated hydrocarbon molecules may therefore offer a promising solution to preventing yeast and mould biofilm formation on materials surfaces, for applications such as air conditioners, biomedical devices, food processing equipment, and others. (paper)

Effects of diurnal temperature variation on microbial community and petroleum hydrocarbon biodegradation in contaminated soils from a sub-Arctic site.

Science.gov (United States)

Akbari, Ali; Ghoshal, Subhasis

2015-12-01

Contaminated soils are subject to diurnal and seasonal temperature variations during on-site ex-situ bioremediation processes. We assessed how diurnal temperature variations similar to that in summer at the site from which petroleum hydrocarbon-contaminated soil was collected affect the soil microbial community and the extent of biodegradation of petroleum hydrocarbons compared with constant temperature regimes. Microbial community analyses for 16S rRNA and alkB genes by pyrosequencing indicated that the microbial community for soils incubated under diurnal temperature variation from 5°C to 15°C (VART5-15) evolved similarly to that for soils incubated at constant temperature of 15°C (CST15). In contrast, under a constant temperature of 5°C (CST5), the community evolved significantly different. The extent of biodegradation of C10-C16 hydrocarbons in the VART5-15 systems was 48%, comparable with the 41% biodegradation in CST15 systems, but significantly higher than CST5 systems at 11%. The enrichment of Gammaproteobacteria was observed in the alkB gene-harbouring communities in VART5-15 and CST15 but not in CST5 systems. However, the Actinobacteria was abundant at all temperature regimes. The results suggest that changes in microbial community composition as a result of diurnal temperature variations can significantly influence petroleum hydrocarbon bioremediation performance in cold regions. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

Contamination of Omnivorous Freshwater Fish Species and Sediments by Chlorinated Hydrocarbons in Poland

Directory of Open Access Journals (Sweden)

Niewiadowska Alicja

2014-10-01

Full Text Available The occurrence and concentrations of organochlorine pesticides and polychlorinated biphenyls (PCBs were determined in 158 muscle samples of bream (Abramis brama and roach (Rutilus rutilus, and 84 samples of sediments collected from 10 river and lake sampling sites in 2011 and 2012. The concentrations of DDTs (p,p’-DDT, o,p’-DDT, p,p’-DDE, and p,p’-DDD, HCH isomers (a-, ß-, and y-HCH, HCB, and PCBs (six indicator PCB congeners 28, 52, 101, 138, 153 and 180 were determined using the capillary gas chromatography. The mean concentrations of DDTs in bream and roach were in the range of 11.2-654 and 4.5-121 ug/kg wet weight respectively, and PCBs were in the range of 1.3-75.9 and 1.1-112 ug/kg wet weight, respectively. Mean concentrations of DDTs and PCBs in sediments were 0.5-270 ug/kg dry weight and ⋋0.1-2.2 ug/kg dry weight respectively. The study showed clear spatial differences in the levels of organochlorine pesticides and PCBs in fish and sediments from different aquatic ecosystems. The highest levels of contaminants were detected in fish and sediments from the Vistula River in vicinity of Cracow. The possible risk to the fish meat consumers and ecological risk were evaluated.

Prompt gamma-ray analysis of chlorine in superpozz cement concrete

Energy Technology Data Exchange (ETDEWEB)

Naqvi, A.A., E-mail: aanaqvi@kfupm.edu.sa [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Kalakada, Zameer [Department of Civil Engineering, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Al-Matouq, Faris A. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Maslehuddin, M. [Center for Engineering Research, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Al-Amoudi, O.S.B. [Department of Civil Engineering, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Ur-Rehman, Khateeb [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia)

2012-11-21

The chlorine concentration in Superpozz (SPZ) cement concrete was analyzed using a newly designed prompt gamma-ray neutron activation (PGNAA) setup utilizing a portable neutron generator. The setup, which mainly consists of a neutron source along with its moderator placed side by side with a shielded gamma-ray detector, allows determining chloride concentration in a concrete structure from one side. The setup has been tested through chlorine detection in chloride-contaminated Superpozz (SPZ) cement concrete specimens using 6.11 and 2.86{+-}3.10 MeV chlorine prompt gamma-rays. The optimum 0.032{+-}0.012 wt% value of Minimum Detectable Concentration (MDC) of chlorine in SPZ cement concrete measured in this study shows a successful application of a portable neutron generator in chloride analysis of concrete structure for corrosion studies.

EDTA addition enhances bacterial respiration activities and hydrocarbon degradation in bioaugmented and non-bioaugmented oil-contaminated desert soils.

Science.gov (United States)

Al Kharusi, Samiha; Abed, Raeid M M; Dobretsov, Sergey

2016-03-01

The low number and activity of hydrocarbon-degrading bacteria and the low solubility and availability of hydrocarbons hamper bioremediation of oil-contaminated soils in arid deserts, thus bioremediation treatments that circumvent these limitations are required. We tested the effect of Ethylenediaminetetraacetic acid (EDTA) addition, at different concentrations (i.e. 0.1, 1 and 10 mM), on bacterial respiration and biodegradation of Arabian light oil in bioaugmented (i.e. with the addition of exogenous alkane-degrading consortium) and non-bioaugmented oil-contaminated desert soils. Post-treatment shifts in the soils' bacterial community structure were monitored using MiSeq sequencing. Bacterial respiration, indicated by the amount of evolved CO2, was highest at 10 mM EDTA in bioaugmented and non-bioaugmented soils, reaching an amount of 2.2 ± 0.08 and 1.6 ± 0.02 mg-CO2 g(-1) after 14 days of incubation, respectively. GC-MS revealed that 91.5% of the C14-C30 alkanes were degraded after 42 days when 10 mM EDTA and the bacterial consortium were added together. MiSeq sequencing showed that 78-91% of retrieved sequences in the original soil belonged to Deinococci, Alphaproteobacteria, Gammaproteobacteia and Bacilli. The same bacterial classes were detected in the 10 mM EDTA-treated soils, however with slight differences in their relative abundances. In the bioaugmented soils, only Alcanivorax sp. MH3 and Parvibaculum sp. MH21 from the exogenous bacterial consortium could survive until the end of the experiment. We conclude that the addition of EDTA at appropriate concentrations could facilitate biodegradation processes by increasing hydrocarbon availability to microbes. The addition of exogenous oil-degrading bacteria along with EDTA could serve as an ideal solution for the decontamination of oil-contaminated desert soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

Removal of Emerging Contaminants and Estrogenic Activity from Wastewater Treatment Plant Effluent with UV/Chlorine and UV/H₂O₂ Advanced Oxidation Treatment at Pilot Scale.

Science.gov (United States)

Rott, Eduard; Kuch, Bertram; Lange, Claudia; Richter, Philipp; Kugele, Amélie; Minke, Ralf

2018-05-07

Effluent of a municipal wastewater treatment plant (WWTP) was treated on-site with the UV/chlorine (UV/HOCl) advanced oxidation process (AOP) using a pilot plant equipped with a medium pressure UV lamp with an adjustable performance of up to 1 kW. Results obtained from parallel experiments with the same pilot plant, where the state of the art UV/H₂O₂ AOP was applied, were compared regarding the removal of emerging contaminants (EC) and the formation of adsorbable organohalogens (AOX). Furthermore, the total estrogenic activity was measured in samples treated with the UV/chlorine AOP. At an energy consumption of 0.4 kWh/m³ (0.4 kW, 1 m³/h) and in a range of oxidant concentrations from 1 to 6 mg/L, the UV/chlorine AOP had a significantly higher EC removal yield than the UV/H₂O₂ AOP. With free available chlorine concentrations (FAC) in the UV chamber influent of at least 5 mg/L (11 mg/L of dosed Cl₂), the total estrogenic activity could be reduced by at least 97%. To achieve a certain concentration of FAC in the UV chamber influent, double to triple the amount of dosed Cl₂ was needed, resulting in AOX concentrations of up to 520 µg/L.

Monitoring the bio-stimulation of hydrocarbon-contaminated soils by measurements of soil electrical properties, and CO2 content and its 13C/12C isotopic signature

Science.gov (United States)

Noel, C.; Gourry, J.; Ignatiadis, I.; Colombano, S.; Dictor, M.; Guimbaud, C.; Chartier, M.; Dumestre, A.; Dehez, S.; Naudet, V.

2013-12-01

Hydrocarbon contaminated soils represent an environmental issue as it impacts on ecosystems and aquifers. Where significant subsurface heterogeneity exists, conventional intrusive investigations and groundwater sampling can be insufficient to obtain a robust monitoring of hydrocarbon contaminants, as the information they provide is restricted to vertical profiles at discrete locations, with no information between sampling points. In order to obtain wider information in space volume on subsurface modifications, complementary methods can be used like geophysics. Among geophysical methods, geoelectrical techniques such as electrical resistivity (ER) and induced polarization (IP) seem the more promising, especially to study the effects of biodegradation processes. Laboratory and field geoelectrical experiments to characterize soils contaminated by oil products have shown that mature hydrocarbon-contaminated soils are characterized by enhanced electrical conductivity although hydrocarbons are electrically resistive. This high bulk conductivity is due to bacterial impacts on geological media, resulting in changes in the chemical and physical properties and thus, to the geophysical properties of the ground. Moreover, microbial activity induced CO2 production and isotopic deviation of carbon. Indeed, produced CO2 will reflect the pollutant isotopic signature. Thus, the ratio δ13C(CO2) will come closer to δ13C(hydrocarbon). BIOPHY, project supported by the French National Research Agency (ANR), proposes to use electrical methods and gas analyses to develop an operational and non-destructive method for monitoring in situ biodegradation of hydrocarbons in order to optimize soil treatment. Demonstration field is located in the South of Paris (France), where liquid fuels (gasoline and diesel) leaked from some tanks in 1997. In order to stimulate biodegradation, a trench has been dug to supply oxygen to the water table and thus stimulate aerobic metabolic bioprocesses. ER and

'Mussel Watch' and chemical contamination of the coasts by polycyclic aromatic hydrocarbons