2002 Progress Report: Metal Removal Capabilities of Passive Bioreactor Systems: Effects of Organic Matter and Microbial Population Dynamics

EPA Grant Number: R829515C003
Subproject: this is subproject number 003 , 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: Metal Removal Capabilities of Passive Bioreactor Systems: Effects of Organic Matter and Microbial Population Dynamics
Investigators: Figueroa, Linda , Ahmann, Dianne , Blowes, David , Carlson, Kenneth H. , DuTeau, Nancy M. , Reardon, Kenneth F. , Shackleford, Charles , Wildeman, Thomas , Woods, Sandra L.
Institution: Colorado School of Mines , Colorado State University
EPA Project Officer: Lasat, Mitch
Project Period: November 1, 2001 through October 31, 2003
Project Period Covered by this Report: November 1, 2001 through October 31, 2002
Project Amount: Refer to main center abstract for funding details.
RFA: Hazardous Substance Research Centers - HSRC (2001) RFA Text |  Recipients Lists
Research Category: Hazardous Waste/Remediation , Land and Waste Management


The overall goal of this research project is to evaluate the effect of organic matter characteristics and types on organic products produced by the microbial populations, and on microbial population distributions and metal speciation and complexation. The following objectives of this research project are to: (1) evaluate the physical, chemical, and biological composition of the components used to create the passive bioreactor (PBR) mixtures; (2) determine if the organic substrate characteristics affect the character and concentration of soluble organic matter, and metal speciation and concentration; (3) determine the variation of microbial population with time and location; and (4) evaluate the use of mathematical models to relate metal removal and transport to various system parameters.

We will use batch and column system experiments to test the proposed hypotheses and meet the project objectives. The project tasks include: (1) solid-phase organic and inorganic material characterization (physical, chemical, and microbial); (2) batch studies on the effect of different PBR mixtures; (3) column studies on the effect of substrate mixtures and perturbations; and (4) fate and transport modeling.

Progress Summary:

The project summary and accomplishments can best be described with respect to the work of the students being funded by the project as follows:

Paolo Hemsi (CSU). Mr. Hemsi is developing a new numerical model for the simulation of the PRB environment, as well as obtaining results under batch (no-flow) simulations and reactive-transport conditions considering both homogeneous and heterogeneous aquifers. Several issues of practical importance in the design of sulfate-reducing permeable reactive barriers are considered, such as restrictions in PRB performance introduced by the kinetics of cellulose decomposition and by the competitive behavior of methanogenic bacteria, as well as by the occurrence of preferential-flow regions due to aquifer heterogeneity.

Miranda Logan (CSM). Ms. Logan is characterizing the microbial communities that exist in passive biosystems to aid in the design of better organic mixtures to sustain long-term sulfide production and metal removal. She has proposed a conceptual model of key microbial processes in passive biosystems. The objective of her investigation is to identify the rate-limiting step(s) in the degradation of organic material as they relate to sulfate-reducing activity in passive biosystems. The results will be used to correlate microbial groups with their functions in passive biosystems. She has used column studies to identify the key microbial processes that influence sulfate-reducing activity in our system. The initial results suggest that this approach will be useful in ascertaining the activities of specific microbial functions.

Jason Seyler (CSM). Soluble and particulate organic fractions, protein, and polysaccharide and lignin content have been correlated to bio-energy production, and methods can be modified for organic substrates commonly used for passive biosystems. Mr. Seyler is characterizing a suite of organic substrates according to modified TAPPI methods. Targeted characteristics include soluble fractions, polysaccharide content, lignin content, and polysaccharide to lignin ratios. Additionally, he characterized metal sorption in column experiments. Preliminary results show that corncobs and walnut hulls are effective at completely removing 50 mg/L of manganese from a synthetic mine water in a column system.

Marie-Helene Robustelli (CSM). Sorption of metals to organic substrates plays a critical role in the removal of metals during the initial phase of a passive bioreactor. Ms. Robustelli investigated the adsorption of zinc to individual organic substrates. Manure and walnut hulls exhibited the highest sorption capacity of zinc.

Sriram Ananthanarayan (CSU). Mr. Ananthanarayan is building a feedback-controlled bench-scale reactor system that will allow us to monitor or set pH and oxidation-reduction potential, as well as to control the headspace. This reactor allows us to measure kinetics of biological reactions under varying environmental conditions. In our case, we will evaluate sulfate reduction kinetics under varying oxidation-reduction potential.

Future Activities:

The future activities of this research project are as follows.

Paolo Hemsi (CSU). Mr. Hemsi will continue the development of a new numerical model for the simulation of transport, microbial, and chemical reactions in the PRB environment.

Miranda Logan (CSM). Ms. Logan will begin a series of new columns and she also will use her new protocol for investigating the effect of soluble substrate spike on the stimulation of methanogens, sulfate reducers, fermenters, and acidogens through mass balances on CH4, CO2, H2, and H2S production, di- and mono-saccharides, and organic acids.

Jason Seyler (CSM). Mr. Seyler will continue his characterization of organic substrate using modified TAPPI methods. He also will begin new batch and column experiments on selected organic substrates next month.

Nicole Messner (CSU). Ms. Messner is a new student on the project and will continue an extensive update of the gray literature on passive bioreactor, wetland, and PRB systems.

HyunSuk Hong (CSU). Also a new student on the project, Mr. Wong will identify pathways of fermenters and acidogens to facilitate the development of primers for functional genes. His work will result in the design of new probes that specifically target fermenter and acidogenic function in the anaerobic bioreactor environment.

Laura Inman (CSU). Ms. Inman is a new research associate on the project, and she will be completing the Reverse Southern-Blot Analysis (RSA) work. A group of 16S rRNA probes currently are available in Dr. DuTeau's lab from other projects that cover a wide range of microorganisms at several taxonomic levels. Ms. Inman will research additional probes that are for functional genes to quantitate microorganisms from several groups including sulfate-reducing bacteria, methanogens, and cellulolytic bacteria.

Kristin Walston (CSU). Also a new research associate on the project, Ms. Walston will be working on the polyacrylamide gel electrophoresis analysis of PCR products from community DNA and RNA. She will perform capillary gel electrophoresis, RFLP analysis, SSCP analysis, and DGGE, as needed.

Supplemental Keywords:

passive bioreactor, metal, sulfate-reducing bacteria, microbiology, remediation, mining, remediation, acid mine drainage, acid mine runoff, aquatic ecosystems, bioreactor, contaminant transport, contaminated waste sites, field monitoring, groundwater, heavy metals, mathematical model, metal removal, mining, mining impacted watershed, mining wastes, natural organic matter, NOM, redox, remediation technologies, risk assessment, runoff, sediment transport, stream ecosystems, suspended sediment., RFA, Industry Sectors, Scientific Discipline, Waste, Contaminated Sediments, Remediation, Mining - NAIC 21, Hazardous Waste, Ecology and Ecosystems, Ecological Risk Assessment, Environmental Engineering, Hazardous, Geology, risk assessment, contaminant transport, contaminated waste sites, suspended sediment, runoff, sediment transport, stream ecosystems, acid mine drainage, remediation technologies, natural organic matter, field monitoring, mining, treatment, aquatic ecosystems, groundwater, heavy metals, mining impacted watershed, mining wastes, redox, bioreactor, acid mine runoff

Relevant Websites:

http://www.engr.colostate.edu/hsrc/ Exit

Progress and Final Reports:

Original Abstract
  • Final

  • Main Center Abstract and Reports:

    R829515    HSRC - Rocky Mountain Regional Hazardous Substance Research Center for Remediation of Mine Waste Sites

    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