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Summary Of Identification Of Rrgulatory Acceptability Of Enhanced Attenuation Categories

Description: Chlorinated solvents once introduced to the subsurface are a persistent contaminant. Though many types of active treatments have been developed and deployed to treat contaminated sites, most sites will ultimately incorporate the use of passive treatments into the remediation process. A process favored by many is the use of Monitored Natural Attenuation that relies on the natural attenuation processes occurring within the system to remediate the contaminants. However, it is likely there will be instances where the natural attenuation processes will be insufficient to reduce the level of contamination to acceptable levels in an acceptable span of time. Rather than redeploying source treatments, the Department of Energy along with the Interstate Technology and Regulatory Council (ITRC) are developing the concept of Enhanced Attenuation (EA). An enhancement is any type of intervention that might be implemented in a source-plume system that increases the magnitude of attenuation by natural processes beyond that which occurs without intervention. Enhanced Attenuation is the result of applying an enhancement or intervention technique that will sustainably manipulate a natural attenuation process leading to an increased reduction in mass flux of contaminants. Efforts are moving forward along several fronts in developing this concept. This effort is a follow-on to initial discussions with site owners, regulators and stakeholder organizations in the development of the concepts of Enhanced Attenuation, the use of mass balance to evaluate the stability of a waste site/groundwater plume, and identification of tools that will support characterization and monitoring efforts for MNA and EA treatments. Those discussions are documented in the report titled ''Summary Document of Workshops for Hanford, Oak Ridge and Savannah River Site as part of the Monitored Natural Attenuation and Enhanced Passive Remediation for Chlorinated Solvents-DOE Alternative Project for Technology Acceleration'' (WSRC, 2003). The objective of this report is to document the May ...
Date: January 4, 2006
Creator: Vangelas, K
Partner: UNT Libraries Government Documents Department

Monitored Natural Attenuation and Enhanced Attenuation for Chlorinated Solvent Plumes - It’s All About Balance

Description: Nature's inherent ability to cleanse itself is at the heart of Monitored Natural Attenuation (MNA). The complexity comes when one attempts to measure and calculate this inherent ability, called the Natural Attenuation Capacity (NAC), and determine if it is sufficient to cleanse the system to agreed upon criteria. An approach that is simple in concept for determining whether the NAC is sufficient for MNA to work is the concept of a mass balance. Mass balance is a robust framework upon which all decisions can be made. The inflows to and outflows from the system are balanced against the NAC of the subsurface system. For MNA to be acceptable, the NAC is balanced against the contaminant loading to the subsurface system with the resulting outflow from the system being in a range that is acceptable to the regulating and decision-making parties. When the system is such that the resulting outflow is not within an acceptable range, the idea of taking actions that are sustainable and that will bring the system within the acceptable range of outflows is evaluated. These sustainable enhancements are being developed under the Enhanced Attenuation (EA) concept.
Date: May 19, 2005
Creator: VANGELAS, KAREN
Partner: UNT Libraries Government Documents Department

Monitored Natural Attenuation of Chlorinated Solvents - Moving Beyond Reuctive Dechlorination

Description: Monitored natural attenuation (MNA), while a remedy of choice for many sites, can be challenging when the contaminants are chlorinated solvents. Even with many high quality technical guidance references available there continue to be challenges implementing MNA at some chlorinated solvent sites. The U.S. Department of Energy, as one organization facing such challenges, is leading a project that will incorporate developing concepts and tools into the existing toolbox for selecting and implementing MNA as a remediation option at sites with chlorinated solvents contamination. The structure and goals of this project were introduced in an article in the Winter 2004 issue of Remediation (Sink et al.). This article is a summary of the three technical areas being developed through the project: mass balance, enhanced attenuation, and characterization and monitoring supporting the first two areas. These topics will be documented in separate reports available from the US Department of Energy Office of Scientific and Technical Information at www.osti.gov.
Date: April 10, 2006
Creator: Vangelas, K
Partner: UNT Libraries Government Documents Department

POTENTIAL ENHANCEMENTS TO NATURAL ATTENUATION: LINES OF INQUIRY SUPPORTING ENHANCED PASSIVE REMEDIATION OF CHLORINATED SOLVENTS

Description: The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Passive Remediation (EPR) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA/EPR. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology and Regulatory Council and the U.S. Environmental Protection Agency (EPA). The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision-making throughout the period of the subject MNA/EPR Alternative Project. To support and more fully document the information presented in the summary report, we are publishing a series of supplemental documents that present the full texts from the technical analyses within the various lines of inquiry (see listing). The following report - documenting our evaluation of the state of the science of the characterization and monitoring process and tools-- is one of those supplemental documents.
Date: June 18, 2004
Creator: Vangelas, K; Tom Early, T; Michael Heitkamp, M; Brian02 Looney, B; David Major, D; Brian Riha, B et al.
Partner: UNT Libraries Government Documents Department

CHARACTERIZATION AND MONITORING OF NATURAL ATTENUATION OF CHLORINATED SOLVENTS IN GROUNDWATER: A SYSTEMS APPROACH

Description: The objective of this document is to examine the use of a phased approach to characterizing and monitoring (C&M) natural attenuation processes and enhanced attenuation processes and to identify promising tools and techniques by which to accomplish the C&M. We will investigate developing techniques, such as molecular-based assessment tools, and existing tools that traditionally have not been used for monitoring the performance of environmental remediation technologies. Case studies will be used to provide examples of how non-traditional methods are being employed as characterization and monitoring tools to support MNA and EA. The document is not focused on a specific group of readers but rather is broadly directed with the intent that readers may gain information useful to their purposes. Thus, regulators may see some future characterization and monitoring techniques; end users may find novel ways to make MNA or EA more effective or efficient at their site; researchers may identify new areas for development or new and better combinations of existing methods. One consequence of this broad approach is that some readers may find certain sections either too rudimentary or too advanced for their needs. Hopefully, all will be able to use at least some of the document.
Date: August 10, 2006
Creator: Looney, B; Michael Heitkamp, M; Gary Wein (NOEMAIL), G; Christopher Bagwell, C; Karen Vangelas, K; Karen-M Adams, K et al.
Partner: UNT Libraries Government Documents Department

Multiple Lines Of Evidence Supporting Natural Attenuation: Lines Of Inquiry Supporting Monitored Natural Attenuation And Enhanced Attenuatin Of Chlorinated Solvents

Description: The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Attenuation (EA) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA/EA. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology Regulatory Council (ITRC) and the United States Environmental Protection Agency (USEPA). The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision making throughout the period of the subject MNA/EA Alternative Project. To support and more fully document the information presented in the summary report, the DOE is publishing a series of supplemental documents that present the full texts from the technical analyses within the various lines of inquiry (see listing). The following report--documenting our evaluation of the state of the science for the lines of evidence for supporting decision-making for MNA--is one of those supplemental documents.
Date: December 31, 2004
Creator: Vangelas, Karen; Widemeirer, T. H.; Barden, M.J.; Dickson, W. Z. & Major, David
Partner: UNT Libraries Government Documents Department

Historical and Retrospective Survey of Monitored Natural Attenuation: A Line of Inquiry Supporting Monitored Natural Attenuation and Enhanced Passive Remediation of Chlorinated Solvents

Description: The Department of Energy is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Passive Remediation(EPR) for chlorinated solvents. This Office of Environmental Management Alternative Project, focuses on providing scientific and policy support for MNA/EPR. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology Regulatory Council and the Environmental Protection Agency. The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision making throughout the period of the subject MNA/EPR Alternative Project. To support and more fully document the information presented in the summary report, we are publishing a series of supplemental documents that present the full texts from the technical analyses within the various lines of inquiry. The following report - documenting our Historical and Retrospective Survey of Monitored Natural Attenuation - is one of those supplemental documents.
Date: January 7, 2004
Creator: Looney, B.B.
Partner: UNT Libraries Government Documents Department

Discussion of DNAPL Migration through a Fractured Perching Layer

Description: The visualization study of 1,1,1-trichloroethane (TCA) infiltration described by Stephens et al. (1998) was an elegant design, clearly demonstrating DNAPL behavior encountering a fractured perched layer. I question, however, their interpretation, stated in both abstract and conclusions, that rapid DNAPL penetration of the fracture was "in contrast to existing mathematical solutions of hydrostatic initial conditions and full saturation below the fracture." I also have a comment regarding the experimental conditions.
Date: January 13, 1999
Creator: Tuck, D.M.
Partner: UNT Libraries Government Documents Department

Acoustically enhanced remediation, Phase 2: Technology scaling

Description: Weiss Associates is conducting the following three phase program investigating the in-situ application of acoustically enhanced remediation (AER) of contaminated unconsolidated soil and ground water under both saturated and unsaturated conditions: Phase I-- laboratory scale parametric investigation; Phase II--technology Scaling; and Phase III--large scale field tests. AER addresses the need for NAPL (either lighter or denser than water: LNAPL or DNAPL, respectively) in high and low permeability sediments, and the remediation of other types of subsurface contaminants (e.g., metals, radionuclides) in low permeability soils. This program has been placed in the U.S. Department of Energy`s (DOE`s) DNAPL product. Phase I indicated that AER could be used to effectively remediate NAPL in high permeability soil, and that removal of NAPL from low permeability soil could be increased since the water flux through these soils was significantly increased. Phase II, Technology Scaling, the subject of this paper, focused on (1) evaluating the characteristics of an AER field deployment system, (2) developing DNAPL flow and transport performance data under acoustic excitation, (3) predicting the effect of acoustic remediation in three-dimensional unconsolidated hydrogeologic conditions, (4) conducting an engineering analysis of acoustical sources, and (5) identifying candidate field site(s) for large-scale field testing of the technology.
Date: December 31, 1996
Creator: Iovenitti, J. L.; Hill, D. G.; Rynne, T. M.; Spadaro, J. F.; Hutchinson, W. & Illangasakere, T.
Partner: UNT Libraries Government Documents Department

Retardation of volatile organic compounds in ground water in low organic carbon sediments

Description: It is postulated that adsorption onto aquifer matrix surfaces is only one of the processes that retard contaminants in ground water in unconsolidated sediments; others include hydrodynamic dispersion, abiotic/biotic degradation, matrix diffusion, partitioning to organic carbon, diffusion into and retention in dead-end pores, etc. This work aims at these processes in defining the K{sub d} of VOCs in sediments with low organic carbon content. Experiments performed include an initial column experiment for VOC (TCE and perchloroethylene(PCE)) retardation tests on geological materials, PCE and TCE data from LLNL sediments, and a preliminary multilayer sampler experiment. The VOC K{sub d}s in low organic carbon permeable aquifer materials are dependent on the VOC composition and independent of aquifer grain size, indicating that sorption was not operative and that the primary retarding factors are diffusion controlled. The program of future experiments is described.
Date: April 1, 1995
Creator: Hoffman, F.
Partner: UNT Libraries Government Documents Department

Lasagna Soil Remediation

Description: Lasagna{trademark} is an integrated, in situ remediation technology being developed which remediates soils and soil pore water contaminated with soluble organic compounds. Lasagna{trademark} is especially suited to sites with low permeability soils where electroosmosis can move water faster and more uniformly than hydraulic methods, with very low power consumption. The process uses electrokinetics to move contaminants in soil pore water into treatment zones where the contaminants can be captured and decomposed. Initial focus is on trichloroethylene (TCE), a major contaminant at many DOE and industrial sites. Both vertical and horizontal configurations have been conceptualized, but fieldwork to date is more advanced for the vertical configuration. Major features of the technology are electrodes energized by direct current, which causes water and soluble contaminants to move into or through the treatment layers and also heats the soil; treatment zones containing reagents that decompose the soluble organic contaminants or adsorb contaminants for immobilization or subsequent removal and disposal; and a water management system that recycles the water that accumulates at the cathode (high pH) back to the anode (low pH) for acid-base neutralization. Alternatively, electrode polarity can be reversed periodically to reverse electroosmotic flow and neutralize pH.
Date: April 1996
Partner: UNT Libraries Government Documents Department

A purge-and-trap capillary column gas chromatographic method for the measurement of halocarbons in water and air

Description: This report describes an automated, accurate, precise and sensitive capillary column purge- and -trap method capable of quantifying CFC-12, CFC-11, CFC-113, CH{sub 3}CCL{sub 3}, and CCL{sub 4} during a single chromatographic analysis in either water or gas phase samples.
Date: June 1, 1996
Creator: Happell, J.D.; Wallace, D.W.R.; Wills, K.D.; Wilke, R.J. & Neill, C.C.
Partner: UNT Libraries Government Documents Department

Inspection and monitoring plan, contaminated groundwater seeps 317/319/ENE Area, Argonne National Laboratory

Description: During the course of completing the Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) in the 317/319/East-Northeast (ENE) Area of Argonne National Laboratory-East (ANL-E), groundwater was discovered moving to the surface through a series of groundwater seeps. The seeps are located in a ravine approximately 600 ft south of the ANL-E fence line in Waterfall Glen Forest Preserve. Samples of the seep water were collected and analyzed for selected parameters. Two of the five seeps sampled were found to contain detectable levels of organic contaminants. Three chemical species were identified: chloroform (14--25 {micro}g/L), carbon tetrachloride (56--340 {micro}g/L), and tetrachloroethylene (3--6 {micro}g/L). The other seeps did not contain detectable levels of volatile organics. The nature of the contaminants in the seeps will also be monitored on a regular basis. Samples of surface water flowing through the bottom of the ravine and groundwater emanating from the seeps will be collected and analyzed for chemical and radioactive constituents. The results of the routine sampling will be compared with the concentrations used in the risk assessment. If the concentrations exceed those used in the risk assessment, the risk calculations will be revised by using the higher numbers. This revised analysis will determine if additional actions are warranted.
Date: October 11, 1996
Partner: UNT Libraries Government Documents Department

Gravity-destabilized nonwetting phase invasion in macro-heterogeneous porous media: Experimental observations of invasion dynamics and scale analysis

Description: The authors designed and conducted experiments in a heterogeneous sand pack where gravity-destabilized nonwetting phase invasion (CO{sub 2} and TCE) could be recorded using high resolution light transmission methods. The heterogeneity structure was designed to be reminiscent of fluvial channel lag cut-and-fill architecture and contain a series of capillary barriers. As invasion progressed, nonwetting phase structure developed a series of fingers and pools; behind the growing front they found nonwetting phase saturation to pulsate in certain regions when viscous forces were low. Through a scale analysis, they derive a series of length scales that describe finger diameter, pool height and width, and regions where pulsation occurs within a heterogeneous porous medium. In all cases, they find that the intrinsic pore scale nature of the invasion process and resulting structure must be incorporated into the analysis to explain experimental results. The authors propose a simple macro-scale structural growth model that assembles length scales for sub-structures to delineate nonwetting phase migration from a source into a heterogeneous domain. For such a model applied at the field scale for DNAPL migration, they expect capillary and gravity forces within the complex subsurface lithology to play the primary roles with viscous forces forming a perturbation on the inviscid phase structure.
Date: February 16, 1999
Creator: GLASS JR.,ROBERT J.; CONRAD,STEPHEN H. & PEPLINSKI,WILLIAM J.
Partner: UNT Libraries Government Documents Department

Bubbleless gas transfer technology for the in situ remediation of chlorinated hydrocarbons

Description: The primary objective of this project is to demonstrate the ability of hydrogen to supply reducing equivalents for the reductive dehalogenation of perchloroethylene (PCE). This objective will be accomplished by two types of activities. First, laboratory experiments will compare the kinetics of hydrogen-mediated dehalogenation with natural routes of loss (hydrolysis and natural attenuation). Secondly, bench-scale column experiments will be performed to demonstrate hydrogen-mediated reductive dehalogenation in aquifer sediments.
Date: October 31, 1999
Creator: Gallagher, J.R. & Kurz, M.D.
Partner: UNT Libraries Government Documents Department

October 1999 Groundwater Sampling and Data Analysis, Distler Brickyard Site, Hardin County, Kentucky

Description: This report describes the results of a sampling event conducted at the Distler Brickyard Superfund Site, Hardin County, Kentucky, October 1999. The purpose of the sampling event was to evaluate the extent of natural biodegradation of chlorinated aliphatic hydrocarbons (CAH) occurring at the Site. Sampling locations were selected to evaluate three areas of the suspected CAH plume: the source area, an axial cross-section, and a downgradient transect. Due to inadequate recharge to and the poor physical condition of some monitoring wells at the Site, the sampling approach was modified to reflect wells that could be sampled. Results indicate that natural anaerobic degradation of chlorinated aliphatic hydrocarbons is occurring in the presumed source area around monitoring well GW-11. The primary contaminant of concern, trichloroethene, migrates downgradient from the source area into the Coarse Grained Alluvium Aquifer at concentrations slightly greater than the Maximum Contaminant Level (MCL). Based on the available, the following hypothesis is proposed: the source area has been remediated through soil removal activities and subsequent anaerobic reductive dechlorination. If this is the case, this Site may be a good candidate for implementation of a monitored natural attenuation remedy. However, more data are necessary before this hypothesis can be confirmed.
Date: March 1, 2000
Creator: Martin, Jennifer P.; Peterson, Lance N. & Taylor, C. J.
Partner: UNT Libraries Government Documents Department

Issues involved with non-characterized control of methanotrophic bacteria

Description: Methane-utilizing bacteria, methanotrophs, have application as biocatalysts in the commodity chemical production, waste treatment and environmental remediation industries. Methanotrophs have the ability to oxidize many chemical compounds into more desired products, such as the production of propylene oxide. Methanotrophs can also degrade toxic compounds such as trichloroethylene. However, there are many physical, chemical and biological problems associated with the continuous oxidation of chemicals. These include, low mass transfer of methane, oxygen and propylene; toxicity of substrates and degradation products, and competition between the growth substrate, i.e., methane and chemical feed stock, e.g., propylene for the biocatalyst. To supervise methanotrophic bioprocesses, an intelligent control system must accommodate any biological limitations, e.g., toxicity, and mitigate the impact of the physical and chemical limitations, e.g., mass transfer of methane and the solubility of propylene. The intelligent control system must have the capability to assess the current conditions and metabolic state of the bacteria; recognize and diagnose instrument faults; and select and maintain sets of parameters that will result in high production and growth.
Date: May 11, 1998
Creator: Stoner, D.L.; Tolle, C.R.; Noah, K.S.; Davis, D.A.; Miller, K.S. & Fife, D.J.
Partner: UNT Libraries Government Documents Department

Oak Ridge National Laboratory/Grand Junction field support for the Lasagna{trademark} technology demonstration

Description: The Oak Ridge National Laboratory (ORNL) Environmental Technology Section (ETS) was tasked by the US Department of Energy EM-50 to provide field support for the Lasagna{trademark} Technology Demonstration from 1994 through 1997. The purpose of the Lasagna Technology Demonstration was to determine the effectiveness of using reductive dehalogenation to degrade trichloroethene (TCE) into its innocuous components. The purpose of this technical memorandum is to document the ORNL-ETS field effort, including results from samples analyzed using the ORNL-ETS field laboratory. The primary contribution from the ORNL-ETS field effort was the effectiveness of the field laboratory, which was found superior to standard methods since significant volatile losses occur during the transport of samples. The field laboratory is particularly effective on demonstration projects where large numbers of samples are collected. Data quality is evaluated by submitting a portion of samples to an analytical laboratory.
Date: August 1, 1998
Creator: Zutman, J.L. & Wilson-Nichols, M.J.
Partner: UNT Libraries Government Documents Department

Initial review of the treatment operations at the Installation Logistics Center, Fort Lewis, Washington

Description: An initial review was conducted of the current treatment operations for remediation of groundwater contaminated with trichloroethene (TCE) at the Fort lewis Logistics Center. Results from this review indicate the two pump-and-treat systems are effectively containing the TCE plume within the upper unconfined aquifer (Vashon Drift). However, mass balance calculations show the existing treatment systems alone will not accomplish the remedial action objective of cleaning up the aquifer to drinking water standards within 30 years as specified in the Record of Decision (ROD). This conclusion is based on the estimated mass of TCE at the source term (51,000 kg), the calculated mass of TCE in the aquifer (4,900 kg), and the removal rate of the pump-and-treat systems that currently ranges from 324 to 667 kg of TCe per year. Four areas within the TCE plume have been identified where enhancements could be made to the existing treatment operations. These are, Area 1 -- the vadose zone source, Area 2 -- the saturated zone source, Area 3 -- a containment area down gradient of Areas 1 and 2, and Area 4 -- the remainder of the plume. This report lists several remedial technologies including new and innovative technologies for these four areas that may help clean up the site to regulatory acceptable levels, shorten the timeframe for cleanup, or significantly reduce currently estimated Installation Restoration program (IRP) life-cycle costs.
Date: July 1, 1998
Creator: Cantrell, K.J.; Liikala, T.L.; Gilmore, T.J. & Last, G.V.
Partner: UNT Libraries Government Documents Department

[A comprehensive signature biomarker analysis of the in-situ viable biomass, community composition, and nutritional status attributes of deep subsurface microbiota]. Final report

Description: The TAN sites contains subsurface sediment contaminated with trichloroethylene (TC). A suite of microbiological analyses, including ester-linked phospholipid fatty acid (PLFA) analysis, were performed to ascertain the microbial ecology associated with TCE degradation processes. The objective of the PLFA analyses were: (1) to determine the distribution of viable microbes throughout a vertical depth profile through the TCE plume, (2) determine the community composition of the viable extant microbiota and (3) relate the data derived from the PLFA analyses to other measures of the in situ microbiota as well as to the presence of TCE degradative products.
Date: September 1, 1998
Partner: UNT Libraries Government Documents Department

Removal of chlorinated and non-chlorinated alkanes in a trickle-bed biofilter

Description: Increasing restrictions in emissions from a variety of industrial settings demand low cost removal of dilute contaminants in air. Many of these contaminants such as volatile organic components (VOCs) and sulfur compounds are biodegradable and can be removed from air streams via biofiltration. The simplest form of biofiltration consists of compost-based systems. More advanced systems designed for unique contaminants are biofilters with bioactive structured packing operating in trickle-bed mode. These advanced systems rely on a microbial consortium capable of degrading the contaminants of concern and the consortium usually is isolated or enriched from a more complex microbial mixture. This paper describes the use of a trickle-bed reactor seeded with a microbial consortium enriched from a methanotrophic culture. The microbial consortium has been found to degrade chlorinated alkanes as the sole carbon source. Degradation rates of alkane mixtures are presented for the trickle-bed as well as results from batch cultures experiments designed to study degradation of various chlorinated and non-chlorinated VOCs.
Date: January 1, 1998
Creator: Klasson, K.T.; Davison, B.H.; Barton, J.W. & Jacobs, J.E.
Partner: UNT Libraries Government Documents Department

Mineralization of trichloroethylene by heterotrophic enrichment cultures

Description: Microbial consortia capable of aerobically degrading greater than 99% of 50 mg/l exogenous trichloroethylene (TCE) have been enriched from TCE contaminated subsurface sediments. Concentrations of TCE greater than 300 mg/l were not degraded nor was TCE used as a sole energy source. Successful electron donors for growth included tryptone-yeast extract, methanol, methane or propane. The optimum temperature for growth was 22--37 C and the ph optimum was 7.0--8.1. Utilization of TCE occurred only after apparent microbial growth had ceased. The major end products recovered were hydrochloric acid and carbon dioxide. Minor products included dichloroethylene, vinylidine chloride and possibly chloroform.
Date: Spring 1988
Creator: Phelps, T. J.; Ringelberg, D.; Mikell, A. T.; White, D. C. & Fliermans, C. B.
Partner: UNT Libraries Government Documents Department