Grantee Research Project Results

Developing and Optimizing Biotransformation Kinetics for the Bio- remediation of Trichloroethylene at NAPL Source Zone Concentrations

EPA Grant Number: R828772C001
Subproject: this is subproject number 001 , established and managed by the Center Director under grant R828772
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: National Research Program on Design-Based/Model-Assisted Survey Methodology for Aquatic Resources
Center Director: Stevens, Don L.
Title: Developing and Optimizing Biotransformation Kinetics for the Bio- remediation of Trichloroethylene at NAPL Source Zone Concentrations
Investigators: Semprini, Lewis , Dolan, Mark E.
Institution: Oregon State University
EPA Project Officer: Aja, Hayley
Project Period: November 1, 2001 through October 31, 2003
Project Amount: Refer to main center abstract for funding details.
RFA: Hazardous Substance Research Centers - HSRC (2001) Recipients Lists
Research Category: Hazardous Waste/Remediation , Land and Waste Management

Objective:

The goal of this project is to develop the capability to reductively dechlorinate high concentrations of TCE and other chlorinated solvents to ethylene through halorespiration. While TCE reductive dechlorination has been demonstrated under a variety of conditions, most laboratory and field projects have been conducted at TCE concentrations of 100 mg/L or less. However near NAPL sources, concentrations of chlorinated aliphatic hydrocarbons approach their solubilities (>1,000 mg/L for TCE and >150 mg/L for PCE). A consortium will be developed and characterized with the ability to reductively dechlorinate high concentrations of TCE to stoichiometric quantities of ethylene. By understanding the factors affecting reductive dechlorination kinetics, we will be better able to optimize the process. This project will prove useful for the remediation of chlorinated aliphatic compounds in the NAPL source zone.

Objectives/Hypothesis:

The specific objectives of this project are to: (1) Develop a culture with the ability to reductively dechlorinate TCE to ethylene at very high concentrations (above 1,000 µM) and in the presence of DNAPL; (2) Characterize microbial growth and measure maximum substrate utilization rates and half velocity coefficients for successive dechlorinations of TCE to ethylene; (3) Characterize the microbial consortium by investigating molecular methods to evaluate the diversity of the mixed culture developed in the kinetic studies; (4) Provide kinetic information and cultures in support of the Project - "Development of the Push-Pull Test to Monitor the Bioaugmentation of Dehalogenating Cultures."

Approach:

A culture will be developed that can rapidly degrade high concentrations of PCE and TCE to ethylene by mixing two cultures. The first culture rapidly transforms PCE to VC, and slowly transforms VC to ethylene at very high PCE and TCE concentrations. The second culture, rapidly transforms vinyl chloride to ethylene. By mixing both cultures, we hope to achieve rapid transformation of PCE and TCE to ethylene. We will use batch studies to determine optimum electron donors for the transformation, and we will use molecular methods to track the two microbial communities. We will also determine electron transfer efficiencies for halorespiration as well as hydrogen thresholds. We will evaluate the effect of varying environmental conditions on reductive dechlorination kinetics. These conditions include the apparent oxidation/reduction potential, pH, electron donor type and concentration, and hydrogen partial pressure.

Expected Results:

The project will result in a well-characterized culture that can rapidly and efficiently transform high concentrations of PCE and TCE completely to ethylene. It will result in a better understanding of the effect of environmental factors on halorespiration. The research should result in the development of in-situ treatment for high concentration source zones via halorespiration. Bioaugmentation of this culture to promote effective in-situ treatment would be a long-term goal of this research.

Publications and Presentations:

Publications have been submitted on this subproject: View all 2 publications for this subproject | View all 168 publications for this center

Journal Articles:

Journal Articles have been submitted on this subproject: View all 1 journal articles for this subproject | View all 69 journal articles for this center

Supplemental Keywords:

Supplemental Keywords: groundwater, reductive dechlorination, microbial activity; NAPLs, RFA, Scientific Discipline, Waste, TREATMENT/CONTROL, POLLUTANTS/TOXICS, Chemical Engineering, Treatment Technologies, Remediation, Environmental Chemistry, Chemicals, Hazardous Waste, Bioremediation, Hazardous, Groundwater remediation, Environmental Engineering, dechlorination, NAPL, Trichloroethylene, chlorinated organic compounds, TCE degradation, biotransformation, reductive dechlorination, chlorinated organics, reductive dechlorination rates, NAPLs, chlorinated solvents, TCE

Progress and Final Reports:

2002

Final

Main Center Abstract and Reports:

R828772    National Research Program on Design-Based/Model-Assisted Survey Methodology for Aquatic Resources

Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R828772C001 Developing and Optimizing Biotransformation Kinetics for the Bio- remediation of Trichloroethylene at NAPL Source Zone Concentrations
R828772C002 Strategies for Cost-Effective In-situ Mixing of Contaminants and Additives in Bioremediation
R828772C003 Aerobic Cometabolism of Chlorinated Aliphatic Hydrocarbon Compounds with Butane-Grown Microorganisms
R828772C004 Chemical, Physical, and Biological Processes at the Surface of Palladium Catalysts Under Groundwater Treatment Conditions
R828772C006 Development of the Push-Pull Test to Monitor Bioaugmentation with Dehalogenating Cultures
R828772C007 Development and Evaluation of Field Sensors for Monitoring Bioaugmentation with Anaerobic Dehalogenating Cultures for In-Situ Treatment of TCE
R828772C008 Training and Technology Transfer
R828772C009 Technical Outreach Services for Communities (TOSC) and Technical Assistance to Brownfields Communities (TAB) Programs
R828772C010 Aerobic Cometabolism of Chlorinated Ethenes by Microorganisms that Grow on Organic Acids and Alcohols
R828772C011 Development and Evaluation of Field Sensors for Monitoring Anaerobic Dehalogenation after Bioaugmentation for In Situ Treatment of PCE and TCE
R828772C012 Continuous-Flow Column Studies of Reductive Dehalogenation with Two Different Enriched Cultures: Kinetics, Inhibition, and Monitoring of Microbial Activity
R828772C013 Novel Methods for Laboratory Measurement of Transverse Dispersion in Porous Media
R828772C014 The Role of Micropore Structure in Contaminant Sorption and Desorption