Grantee Research Project Results
2005 Progress Report: Assessment of Electrokinetic Injection of Amendments for Remediation of Acid Mine Drainage
EPA Grant Number: R829515C011Subproject: this is subproject number 011 , established and managed by the Center Director under grant R829515
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: Center for Comprehensive, optimaL, and Effective Abatement of Nutrients
Center Director: Arabi, Mazdak
Title: Assessment of Electrokinetic Injection of Amendments for Remediation of Acid Mine Drainage
Investigators: Carlson, Kenneth H. , Pruden, Amy
Institution: Colorado State University
EPA Project Officer: Aja, Hayley
Project Period: October 1, 2003 through September 30, 2006
Project Period Covered by this Report: October 1, 2004 through September 30, 2005
RFA: Hazardous Substance Research Centers - HSRC (2001) Recipients Lists
Research Category: Hazardous Waste/Remediation , Land and Waste Management
Objective:
The overall objective of this research project is to evaluate the technical feasibility and cost effectiveness of using electrokinetic injection delivery techniques for the remediation of acid mind drainage. The specific objectives are to: (1) determine the transport efficacy of electrokinetic injection for delivery of organic electron donors; (2) determine the efficacy of unamended electrokinetic injection for removal of metal contaminants as oxides and hydroxides; (3) determine the efficacy of electrokinetic injection for delivery of organic electron donors for stabilizing metals in acid mind drainage (AMD) and characterize the microbial community that is stimulated during various electrokinetic injection process configurations; and (4) compare order of magnitude costs and operational issues of electrokinetic injection of electron donors for AMD remediation.
Progress Summary:
The results from the first objective proved that the transport of organic acids using electrokinetic injection is a viable means to introduce amendments into the soil. The results indicate that an organic acid can be uniformly transported under varying soil conditions at low current levels. Preliminary results from the second objective indicate marginal removal of metals in the unamended electrokinetic mode.
Comparisons of candidate substrates were conducted to determine the optimal organic acid to be introduced as an amendment to the subsurface. The experiment monitored the production of CH4, H2S, and CO2 in the headspace daily and cumulative gas production. The results indicated that citrate or lactate would be the preferable organic electron donor.
Future Activities:
Upon completion of the unamended electrokinetic remediation tests, the amended tests will be conducted using citrate or lactate. Recent results indicate that the presence of hydrogen (H2) may be critical for operating a sulfate reducing bioreactors barrier without sulfate reduction stalling before completion. The role of hydrogen in the electrokinetic columns will be researched along with different substrates (lactate and citrate). In addition, the microbial communities present in the soil column studies will be analyzed.
Supplemental Keywords:
acid mine drainage, acid mine runoff, anaerobic degradation, anaerobic microbial processes, anaerobic treatment, aquatic ecosystems, biodegradation, contaminant transport, contaminated waste sites, electrokinetics, heavy metals, metal removal, microbial degradation, mining wastes,, RFA, Scientific Discipline, Industry Sectors, INTERNATIONAL COOPERATION, TREATMENT/CONTROL, Waste, Hazardous, Remediation, Ecological Risk Assessment, Waste Treatment, Contaminated Sediments, Hazardous Waste, Geology, Mining - NAIC 21, Bioremediation, Environmental Engineering, contaminant transport, heavy metals, metal removal, anaerobic treatment, microbial degradation, mining, acid mine drainage, treatment, mining wastes, risk assessment, electrokinetics, fate and transport modeling, transport models, remediation technologies, acid mine runoff, biodegradation, groundwater, sediment transport, field monitoring, anaerobic degradation, aquatic ecosystems, contaminated waste sites, anaerobic microbial processes, runoffRelevant Websites:
http://www.engr.colostate.edu/hsrc/ Exit
Progress and Final Reports:
Original AbstractMain Center Abstract and Reports:
R829515 Center for Comprehensive, optimaL, and Effective Abatement of Nutrients Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R829515C001 Redox Transformations, Complexation and Soil/Sediment
Interactions of Inorganic Forms of As and Se in Aquatic Environments: Effects
of Natural Organic Matter
R829515C002 Fate and Transport of Metals and Sediment in Surface Water
R829515C003 Metal Removal Capabilities of Passive Bioreactor Systems: Effects of Organic Matter and Microbial Population Dynamics
R829515C004 Evaluating Recovery of Stream Ecosystems from Mining Pollution:
Integrating Biochemical, Population, Community and Ecosystem Indicators
R829515C005 Rocky Mountain Regional Hazardous Substance Research Center
Training and Technology Transfer Program
R829515C006 Technical Outreach Services for Communities and Technical Assistance to Brownfields
R829515C007 Evaluation of Hydrologic Models for Alternative Covers at Mine Waste Sites
R829515C008 Microbial Reduction of Uranium in Mine Leachate by Fermentative and Iron-Reducing Bacteria
R829515C009 Development and Characterization of Microbial Inocula for High-Performance Passive Treatment of Acid Mine Drainage
R829515C010 Reactive Transport Modeling of Metal Removal From Anaerobic Biozones
R829515C011 Assessment of Electrokinetic Injection of Amendments for Remediation of Acid Mine Drainage
R829515C012 Metal Toxicity Thresholds for Important Reclamation Plant Species of the Rocky Mountains
R829515C013 An Improved Method for Establishing Water Quality Criteria for Mining Impacted Streams
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.