Jump to main content.

Research Project Search
 Enter Search Term:
   
 NCER Advanced Search

2004 Progress Report: Development and Characterization of Microbial Inocula for High-Performance Passive Treatment of Acid Mine Drainage

EPA Grant Number: R829515C009
Subproject: this is subproject number 009 , 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: HSRC - Rocky Mountain Regional Hazardous Substance Research Center for Remediation of Mine Waste Sites
Center Director: Shackelford, Charles D.
Title: Development and Characterization of Microbial Inocula for High-Performance Passive Treatment of Acid Mine Drainage
Investigators: Reardon, Kenneth F. , Pruden, Amy
Institution: Colorado State University
EPA Project Officer: Lasat, Mitch
Project Period: October 1, 2003 through September 30, 2006
Project Period Covered by this Report: October 1, 2003 through September 30, 2004
RFA: Hazardous Substance Research Centers - HSRC (2001)
Research Category: Hazardous Waste/Remediation

Description:

Objective:

The overall objective of this research project is to investigate the role of inocula in the performance of sulfate-reducing permeable reactive zones (SR-PRZs). Although our past work on project R829515C003 focused on the role of the organic matter used, the current research project focuses on the role of the microbes. We currently are applying the molecular tools that we developed in project R829515C003 to characterizing and comparing inocula. Inocula will be compared with respect to three parameters: (1) startup time; (2) sulfate reduction rate; and (3) activity retention time.

Progress Summary:

Pilot Column Study

The purpose of this study was to provide proof-of-concept that the source of inoculum can impact the overall column performance. Three pairs of duplicate columns were operated in parallel, differing only in the source of the inoculum: (1) dairy manure; (2) acclimated column material (from a project R829515C004 column); and (3) no inoculum. The columns were fed simulated mine drainage water containing 10 mg/L zinc, 5 mg/L cadmium, and 20 mg/L iron(II) at a pH of 5.5 and were operated for 5 months. This study demonstrated that the sulfate removal rate, the metal removal rate, and the extent of pH neutralization all were superior in the columns inoculated with the acclimated column material.

Batch Study

The purpose of the batch study is to further screen and test promising inocula, which will provide the basis for development of optimized inocula for SR-PRZs. Currently, five inocula are being compared: (1) dairy manure; (2) acclimated column material; (3) anaerobic digester sludge; (4) LUTR Montana barrier; and (5) Peerless Jenny Montana barrier. Also, bottles without inocula have been included in the study, and the effect of agitating the bottles also is being tested. The headspaces of bottles are being analyzed twice per day for carbon dioxide, methane, and hydrogen sulfide by gas chromatography (GC TCD). In addition, overall gas production is being monitored weekly, as is the structure of the microbial community, sulfates, metals, and pH. Initial results suggest that the LUTR Montana barrier inoculum is superior with respect to its overall gas production and startup time, whereas the Peerless Jenny barrier inoculum is performing equally to no inoculum.

Microbial Community Analysis

We are applying the various molecular tools developed in project R829515C004 to characterize the inocula and monitor the behavior of the microbial communities during startup, active sulfate reduction periods, and decline of sulfate-reduction. We then will use these tools as guides for optimizing inocula for site-specific SR-PRZ concerns. We have used denaturing gradient gel electrophoresis to monitor and compare the columns and have been able to identify several functional groups (cellulose degraders, fermenters, and sulfate reducers) in the columns. We also have compared the relative concentrations of Desulfotomaculum (gram-positive sulfate reducers in the Clostridium group) and found that they were highest in the most active sulfate-reducing columns, as expected. Unexpectedly, however, Desulfotomaculum were lower in the columns inoculated with dairy manure than in the columns that were not inoculated at all. This supports the results of the column study, in which uninoculated columns performed equivalently with dairy manure inoculated columns, and suggests that the “wrong” inoculum does not provide any advantage over no inoculum and in some cases may even be worse.

Future Activities:

The investigators did not report any future activities.

Publications/Presentations:See the list of publications/presentations included in the 2004 Annual Report Summary for R829515, which is the overall report for the Rocky Mountain Regional Hazardous Substance Research Center.

Supplemental Keywords:

Technical Outreach Services for Communities, TOSC, Technical Assistance to Brownfields, TAB, groundwater, industry sectors, waste, water, ecological risk assessment, ecology, ecosystems, ecology and ecosystems, environmental chemistry, environmental engineering, geology, geochemistry, toxicology, microbiology, hazardous, hazardous waste, mining-NAIC 21, selenium, acid mine drainage, acid mine runoff, aquatic ecosystems, arsenic, contaminant transport, contaminated sediments, contaminated marine sediment, contaminated waste sites, contaminated sites, contaminated soil, field monitoring, mining-impacted runoff, sediment transport, stream ecosystems, suspended sediment, sediments, mining, remediation, metal mobility, subsurface, extraction of metals, heavy metals, leaching of toxic metals, metal release, metal wastes, metals, metals-contaminated soil, mining wastes, remediation technologies, risk assessment, , Industry Sectors, INTERNATIONAL COOPERATION, TREATMENT/CONTROL, Scientific Discipline, Waste, RFA, Remediation, Geology, Waste Treatment, Ecological Risk Assessment, Hazardous Waste, Environmental Engineering, Contaminated Sediments, Hazardous, Mining - NAIC 21, Ecology and Ecosystems, Treatment Technologies, Bioremediation, heavy metals, risk assessment, runoff, treatment, biodegradation, microbial degradation, mining impacted watershed, redox, contaminated waste sites, mining, mining wastes, stream ecosystems, acid mine runoff, suspended sediment, permeable reactive barrier, acid mine drainage, groundwater, metal removal, remediation technologies, contaminant transport, natural organic matter, aquatic ecosystems, sediment transport, field monitoring, sulfate reducing bacterium
Relevant Websites:

http://www.engr.colostate.edu/hsrc/ exit EPA

Progress and Final Reports:
Original Abstract
2005 Progress Report


Main Center Abstract and Reports:
R829515    HSRC - Rocky Mountain Regional Hazardous Substance Research Center for Remediation of Mine Waste Sites

Top of page

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.

Local Navigation

Jump to main content.