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Continuous-Flow Column Studies of Reductive Dehalogenation with Two Different Enriched Cultures: Kinetics, Inhibition, and Monitoring of Microbial Activity
EPA Grant Number: R828772C012Subproject: this is subproject number 012 , 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: HSRC (2001) - Western Region Hazardous Substance Research Center for Developing In-Situ Processes for VOC Remediation in Groundwater and Soils
Center Director: Semprini, Lewis
Title: Continuous-Flow Column Studies of Reductive Dehalogenation with Two Different Enriched Cultures: Kinetics, Inhibition, and Monitoring of Microbial Activity
Investigators: Semprini, Lewis , Dolan, Mark E. , Spormann, Alfred M.
Institution: Oregon State University , Stanford University
EPA Project Officer: Lasat, Mitch
Project Period: September 1, 2001 through August 31, 2006
RFA: Hazardous Substance Research Centers - HSRC (2001)
Research Category: Hazardous Waste/Remediation
Description:
Objective:This project is evaluating the transformation of chlorinated ethenes in sequencing batch reactors and continuous-flow column studies with the Point Mugu (MU) and the Evanite (EV) cultures that have been developed and kinetically characterized in our earlier WRHSRC project (Yu and Semprini, 2004; Yu, et al., in press). The overall goals of the project are to: (1) determine if kinetic parameters that were derived under batch conditions can be used to model the sequential transformation of chlorinated ethenes spatially in the columns; (2) evaluate if the predicted performance of the two enrichment cultures is achieved and to test methods that may distinguish the MU culture from the EV culture; (3) apply molecular methods such as FISH and Real-Time PCR to determine the spatial distribution of the cultures and quantify the dehalogenating biomass within the column; (4) apply RNA-based methods to determine energetically based TCE and VC-dehalogenating activity temporally and spatially within the column; (5) apply molecular based activity tests, such as transformation of fluorinated analogs, to determine dehalogenating activity that develops within the column; (6) study toxicity and inhibition that may result from the presence of co-contaminants, such as chloroform or acetylene; and (7) compare the results from modeling, molecular, and activity based results.
Rationale
Biologically driven reductive dehalogenation is becoming a commonly used process for remediating groundwater contaminated with chlorinated ethenes and mixtures of other chlorinated aliphatic hydrocarbons. Several studies have now demonstrated that engineered systems of enhanced reductive dehalogenation can result in complete dehaogenation of PCE and TCE to ethene. Bioaugmentation of microbial consortium that contain phylogenetic relatives of Dehaloccoides etheneogenes has promoted the complete dehalogenation of PCE or TCE to ethene. Remediation of source zones containing high concentrations of PCE and TCE via reductive halogenation is also being considered. Few studies have been performed that have evaluated changes in community structure and function under flow conditions where spatial and temporal changes in transformation and community structure can result. Column studies to date have not been performed with cultures with well defined kinetic parameters or have employed RNA-based methods to characterize the microbial activity. This study will therefore compare results of modeling, molecular, and activity based measurements in a series of continuous flow column studies.
Publications and Presentations:Publications have been submitted on this subproject: View all 5 publications for this subproject | View all 163 publications for this center
Journal Articles:Journal Articles have been submitted on this subproject: View all 2 journal articles for this subproject | View all 62 journal articles for this center
Progress and Final Reports:
2004 Progress Report
2005 Progress Report
Main Center Abstract and Reports:
R828772 HSRC (2001) - Western Region Hazardous Substance Research Center for Developing In-Situ Processes for VOC Remediation in Groundwater and Soils
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
R828772C005 Effects of Sorbent Microporosity on Multicomponent Fate
and Transport in Contaminated Groundwater Aquifers
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