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Annual Report Fiscal Year 2003
Prepared by:
MSE Technology Applications, Inc.
P.O. Box 4078
Butte, Montana 59702
Mine Waste Technology Program
Interagency Agreement Management Committee
IAG ID NO. DW89938870-01-0
Prepared for:
U.S. Environmental Protection Agency
Office of Research and Development
National Risk Management Research Laboratory
26 W. Martin Luther King Drive
Cincinnati, Ohio 46268
and
U.S. Department of Energy
National Energy Technology Laboratory
P.O. Box 10940
Pittsburgh, Pennsylvania 15236-0940
Contract No. DE-AC22-96EW96405
Contents
Vision Statement for the Mine Waste Technology Program
Program Manager's Executive Summary
Introduction
Program Overview
Organizational Structure
Looking Ahead to FY04
Activities
Descriptions, Accomplishments, and Future Direction
Activity I Overview/Issues Identification
Activity II Overview/Quality Assurance
Activity III Overview/Pilot-Scale DemonstrationsProject 3 Sulfate-Reducing Bacteria Demonstration
Project 8 Underground Mine Source Control
Project 15 Tailings Source Control
Project 16 Integrated Passive Biological Treatment Process Demonstration
Project 21 Integrated Process for Treatment of Berkeley Pit Water
Project 24 Improvements in Engineered Bioremediation of Acid Mine Drainage
Project 26 Prevention of Acid Mine Drainage Generation from Open-Pit Mine Highwalls
Project 29 Remediation Technology Evaluation at the Gilt Edge Mine
Project 30 Acidic/Heavy Metal-Tolerant Plant Cultivars Demonstration, Anaconda Smelter Superfund Site
Project 33 Microencapsulation to Prevent Acid Mine Drainage
Project 34 Bioremediation of Pit Lakes (Guilt Edge Mine)
Project 38 Contaminant Speciation in Riparian Soils Demonstration
Project 39 Long-Term Monitoring of Permeable Treatment Wall Demonstration
Project 40 Electrochemical Tailings CoverActivity IV Overview/Bench-Scale Testing
Projects 22 and 26 Organic Matter Degradation Rate in a Sulfate Reducing Wetland Phases I and II
Project 23 Sulfate Removal Technology Development
Project 24 Algal Bioremediation of the Berkeley Pit Lake System–Phase III
Project 25 Heavy and Toxic Metal Remediation Using Reductive Precipitation/Cementation
Project 27 Subaqueous Oxidation of Pyrite and Stable Isotope Geochemistry of an Acidic Pit Lake
Project 28 Effects of Plant Species and Rodents on the Sequestration and/or Movement of Mercury from Reclaimed Sites
Project 29 Field Monitoring and Evaluation of Reclamation Strategies of Abandoned Mine Sites in the Helena National ForestActivity V Overview/Technology Transfer
Activity VI Overview/Training and Education
Financial Summary
Completed Projects
Key Contacts
Vision Statement for the Mine Waste Technology Program
Background
Mining activities in the United States (not counting coal) produce between 1 and 2 billion tons of mine waste annually. These activities include extraction and beneficiation of metallic ores, phosphate, uranium, and oil shale. Over 130,000 of these noncoal mines, concentrated largely in nine western states, are responsible for polluting over 3,400 miles of streams and over 440,000 acres of land. About seventy of these sites are on the National Priority List for Superfund remediation. In the 1985 Report to Congress on the subject, the total noncoal mine waste volume was estimated at 50 billion tons, with 33% being tailings, 17% dump/heap leach wastes and mine water, and 50% surface and underground wastes. Since many of the mines involve sulfide minerals, the production of acid mine drainage (AMD) is a common problem from these abandoned mine sites. The cold temperatures in the higher elevations and heavy snows frequently prevent winter site access. The combinations of acidity, heavy metals, and sediment have severe detrimental environmental impacts on the delicate ecosystems in the West.
Philosophy/Vision
End-of-pipe treatment technologies, while essential for short-term control of environmental impact from mining operations, are a stopgap approach for total remediation. Efforts need to be made on improving the end-of-pipe technologies to reduce trace elements to low levels for applications in ultra-sensitive watersheds and for reliable operation in unattended, no power situations. The concept of pollution prevention, emphasizing at-source control and resource recovery, is the approach of choice for the long-term solution. Our objective in the Mine Waste Technology Program is not to assess the environmental impacts of the mining activities, but it is to develop and prove technologies that provide satisfactory short- and long-term solutions to the remedial problems facing abandoned mines often in remote sites and the ongoing compliance problems associated with active mines.
Approach
There are priority areas for research, in the following order of importance:
Source Controls, Including In Situ Treatments and Predictive Techniques
It is far more effective to attack the problem at its source than
to attempt to deal with diverse and dispersed wastes, laden with
wide varieties of metal contaminants. At-source control technologies,
such as sulfate-reducing bacteria; biocyanide oxidation for heap
leach piles; transport control/pathway interruption techniques,
including infiltration controls, sealing, grouting, and plugging
by ultramicrobiological systems; and AMD production prediction
and control techniques should strive toward providing a permanent
solution, which is the most important goal of the program.
Treatment Technologies
Improvements in short-term end-of-pipe treatment options are essential
for providing immediate alleviation of some of the severe environmental
problems associated with mining, and particularly with abandoned
metal mines. Because immediate solutions may be required, this
area of research is extremely important for effective environmental
protection.
Resource Recovery
In the spirit of pollution prevention, much of the mining wastes,
both AMD (e.g., over 25 billion gallons of Berkeley Pit water)
and the billions of tons of mining/beneficiation wastes, represent
a potential resource as they contain significant quantities of
heavy metals. While remediating these wastes, it may be feasible
to incorporate resource recovery options to help offset remedial
costs.
The Partnerships
In these days of ever-tightening budgets, it is important that we leverage our limited funding with other agencies and with private industry. The Bureau of Land Management and Forest Service actively participate by providing sites for demonstrations of the technologies. It is important where these technologies have application to active mining operations to achieve cost-sharing partnerships with the mining industry to test the technologies at their sites. Fortunately, the program has strong cooperation from industry. Within the U.S. Environmental Protection Agency (EPA), the program is coordinated and teamed, where appropriate, with the Superfund Innovative Technology Evaluation (SITE) program to leverage the funding and maximize the effectiveness of both programs. We have strong interaction, cooperation, and assistance from the mining teams in the EPA Regional Offices, especially Regions 7, 8, 9, and 10. Several joint projects are underway, and more are planned.
A considerable resource and willing partner is the University system (such as Montana Tech of the University of Montana, University of Montana?Missoula, Montana State University?Bozeman, and the Center for Biofilm Engineering), which can conduct the more basic type of research related to kinetics, characterization, and bench-scale tests at minimal cost to the program, while at the same time providing environmental education that will be useful to the region and to the Nation. The Mine Waste Technology Program supports cooperative projects between the educational system and the mining industry, where teams of students conduct research of mine site-specific problems, often with monetary support from the industry. The results are made available to the industry as a whole and to the academic community.
The Science
The research program is peer-reviewed annually by the Technical Integration Committee (TIC), who technically reviews all ongoing and proposed projects. The TIC is composed of technical experts from EPA and the cooperating agencies, academia, environmental stakeholders, and industry and their consultants. Final reports are additionally peer-reviewed in accordance with EPA’s strict policy for scientific products.
/s/
Roger C. Wilmoth
Chief, Industrial Multimedia Branch
Sustainable Technology Division
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
(MS 445)
26 W. Martin Luther King Drive
Cincinnati, OH 45268
Program Manager's
Executive Summary
The Mine Waste Technology Program (MWTP) Annual Report for fiscal 2003 summarizes the results and accomplishments for the various activities within the Program. The MWTP has met its goals by providing assistance to the public and forming cooperative teams drawn from government, industry, and private citizens. The funds expended have returned tangible results, providing tools for those faced with mine waste remediation challenges.
After 13 years, everyone involved with the MWTP can look with pride to the Program's success. Technology development and basic research has proceeded successfully through the efforts of MSE Technology Applications, Inc. (MSE) and its prime subcontractor Montana Tech of the University of Montana (Montana Tech).
MSE has developed thirty-seven field-scale demonstrations, several of which are attracting attention from industry and public stakeholders involved in the cleanup of mine wastes.
Montana Tech has developed twenty-four bench-scale projects, six of which are ongoing during 2003. This cooperative effort provides cutting edge research for the program as well as educational opportunities.
Numerous activities are associated with the development of a field-scale demonstration. Among these activities is the need to acquire federal and state permits; secure liability limiting access agreements; develop and adhere to health and safety operation plans and quality assurance project plans; and comply with the National Environmental Policy Act and other federal and state environmental oversight statutes.
The Program has received substantial support from state and federal agencies, the mining industry, environmental organizations, and numerous associations interested in mining and development of natural resources at state, regional, and national levels.
Montana Tech continued the post-graduate degree program with a mine waste emphasis. The quality of short courses offered by Montana Tech is becoming highly recognized by the mining industry and mine waste remediation community. Graduates of the program are fast becoming leaders for industry and government agencies helping to promote technology usage and acceptance worldwide.
The MWTP recognizes its major accomplishments and looks forward to providing new and innovative technologies; meeting the challenges of mine waste remediation; and providing economical, permanent solutions to the nation's mining waste problems.
/s/
Jeff LeFever
MSE MWTP Program Manager
Introduction
Mining waste generated by active and inactive mining production facilities and its impact on human health and the environment are a growing problem for Government entities, private industry, and the general public. The nation's reported volume of mine waste is immense. Presently, there are more than sixty mining impacted sites on the U.S. Environmental Protection Agency's National Priorities List.
Environmental impacts associated with inactive and abandoned mines are common to mining districts around the country, as shown in Table 1.
Total estimated remediation costs for these states range from $4 to $45 billion.
Health effects from the predominate contaminants in mine waste range from mild irritants to proven human carcinogens, such as cadmium and arsenic. The large volume of mine wastes and consequential adverse environmental and human health effects indicates an urgency for cleanup of abandoned, inactive, and active mining facilities. The environmental future of the United States depends in part on the ability to deal effectively with mine waste problems of the past and present, and more importantly, to prevent mine waste problems in the future.
The fiscal year (FY) 1991 Congressional Appropriation allocated $3.5 million to establish a pilot program in Butte, Montana, for evaluating and testing mine waste treatment technologies. The Mine Waste Technology Program (MWTP) received additional appropriations of $3.5 million in FY91, $3.3 million in FY94, $5.9 million in FY95, $2.5 million in FY96, $7.5 million in FY97, $6.0 million in FY98 and FY99, $4.3 million in FY00, $3.9 million in FY01, $3.9 million in FY02, and $3.5 million in FY03.
The projects undertaken by this Program focus on developing and demonstrating innovative technologies at both the bench- and pilot-scale that treat wastes to reduce their volume, mobility, or toxicity. Fifty percent of the budget is allocated to focus areas such as: 1) source control for preventing metal leaching and acid mine drainage; 2) techniques for treating low-flow metal laden/acid mine drainage in remote settings. To convey the results of these demonstrations to the user community, the mining industry, and regulatory agencies, MWTP includes provisions for extensive technology transfer and educational activities. This report summarizes the progress of the MWTP activities in FY03.
| State | Estimated Number of Sites or Land Areas | Classification and Estimated Number |
|---|---|---|
| Alaska | 10,910 sites | mine dumps- 1,000 acres disturbed land - 27,680 acres mine openings - 500 hazardous structures - 300 |
| Arizona | 95,000 sites | polluted water - 2,002 acres mine dumps - 40,000 acres disturbed land - 96,652 acres mine openings - 80,000 California 11,500 sites polluted water - 369,920 acres mine dumps - 171 acres mine openings - 1,685 |
| Colorado | 20,229 sites covering 26,584 acres | polluted water - 830,720 acres mine dumps - 11,800 acres disturbed land - 13,486 acres mine openings - 20,229 hazardous structures - 1,125 |
| Idaho | 8,500 sites covering 18,465 acres polluted water - 84,480 acres |
mine dumps - 3,048 acres disturbed land - 24,495 acres mine openings - 2,979 hazardous structures - 1,926 |
| Michigan | 400–500 sites | Accurate information not available. |
| Montana | 19,751 sites covering 11,256 acres | polluted water - 715,520 acres mine dumps - 14,038 acres disturbed land - 20,862 acres mine openings - 4,668 hazardous structures - 1,747 |
| Nevada | 400,000 sites | Accurate information not available. |
| New Mexico | 7,222 sites covering 13,585 acres | polluted water - 44,160 acres mine dumps - 6,335 acres disturbed land - 25,230 acres mine openings - 13,666 hazardous structures - 658 |
| Oregon | 3,750 sites | polluted water - 140,800 acres mine dumps - 180 acres disturbed land - 61,000 acres mine openings - 3,750 hazardous structures - 695 |
| South Dakota | 4,775 acres | Accurate information not available. |
| Texas | 17,300 acres | Accurate information not available. |
| Utah | 14,364 sites covering 12,780 acres | polluted water - 53,120 acres mine dumps - 2,369 acres disturbed land - 18,873 acres mine openings - 14,364 hazardous structures - 224 |
| Wisconsin | 200 acres | Accurate information not available. |
| Wyoming | 5,000 acres | Accurate information not available. |
Information was collected from the following
sources and is only an estimate of the acid mine drainage
problem.
|
||
Program Overview
Fiscal Year 2003 Program
This Mine Waste Technology Program (MWTP) annual report covers the period from October 1, 2002, through September 30, 2003. This section of the report explains the MWTP organization and operation.
Mission
The mission of the MWTP is to provide engineering solutions to national environmental issues resulting from the past practices of mining and smelting of metallic ores. In accomplishing this mission, the MWTP develops and conducts a program that emphasizes treatment technology development, testing and evaluation at bench- and pilot-scale, and an education program that emphasizes training and technology transfer. Evaluation of the treatment technologies focuses on reducing the mobility, toxicity, and volume of waste; implementability; short- and long-term effectiveness; protection of human health and the environment; community acceptance; and cost reduction.
The statement of work provided in the Interagency Agreement between the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy identifies six activi¬ties to be completed by MWTP. The following descriptions identify the key features of each and the organization performing the activity.
Activity I: Issues Identification
Montana Tech of the University of Montana (Montana Tech) is documenting various mine waste technical issues and innovative treatment technologies. These issues and technologies are then screened and prioritized in volumes related to a specific mine waste problem. In 2003, Volume 10, Issues Identification and Technology Prioritization Report–Mercury, was published. The Berkeley Pit monograph report titled A Summary of Berkeley Pit Research: The Resource Recovery and Mine Waste Technology Programs was also published. Technical issues of primary interest include numerous mobile toxic constituents such as arsenic, cyanide, mercury, nitrate, selenium, and thallium as well as sulfate-reducing bacteria, water/acid generation, pyrite-rich mine wastes, and pit lakes. Wasteforms reviewed related to these issues included point- and nonpoint-source acid mine drainage, abandoned mine acid mine drainage, streamside tailings, impounded tailings, soils, and heap leach-cyanide/acid tailings. Furthermore, under this task, Montana Tech produced an interactive CD-ROM based summary of the program including the Annual Report and Activities in Depth CD, Snapshot CD (Version 1.0 and 2.1), and Combo CD (Version 3.1). The CDs can be obtained from the personnel listed in the Contacts Section of this report. Various personnel contacts and research information are also available on the web at: http://www.epa.gov/ORD/NRMRL/std/mtb/.
Activity II: Quality Assurance
The MWTP operates under an EPA approved Quality Management Plan (QMP). The QMP is available on http://www.epa.gov/ORD/NRMRL/std/mtb/. This plan provides specific instructions for data gathering, analyzing, validating, and reporting for all MWTP activities. The QMP also contains guidance related to program roles and responsibilities, training, work flow processes, oversight, corrective action procedures, and quality improvement. In addition to the QMP, each MWTP project is performed under the auspices of an EPA-approved Quality Assurance Project Plan.
Activity III: Pilot-Scale Demonstrations
Pilot-scale demonstration topics were chosen after a thorough investigation of the associated technical issues was performed, the specific wasteform to be tested was identified, peer review was conducted, and sound engineering and cost determination of the demonstration were formulated.
MSE continued fourteen field-scale demonstrations during fiscal 2003. One field demonstration was completed, i.e., Project 36.
Activity IV: Bench-Scale Experiments
Montana Tech had eight ongoing projects during fiscal 2003. Five projects were begun: 1) Project 25–Metal Remediation/Cementation; 2) Project 26–Organic Matter–Phase 2; 3) Project 27–Subaqueous Pyrite Oxidation; 4) Project 28–Mercury Transportation from Reclaimed Mine Sites; and 5) Project 29–Monitoring and Evaluation of Remediation Strategies in the Helena National Forest.
Activity V: Technology Transfer
MSE is responsible for preparing and distributing reports for the MWTP. These include routine weekly, monthly, quarterly, and annual reports; technical progress reports; and final reports for all MWTP activities. MSE also publicizes information developed under MWTP in local, regional, and national publications. Other means of information transfer include public meetings, workshops, and symposiums.
Activity VI: Educational Programs
Montana Tech has developed a post-graduate degree program with a mine waste emphasis. The program contains elements of geophysical, hydrogeological, environmental, geochemical, mining and mineral processing, extractive metallurgical, and biological engineering.
Figure 1. MWTP organizational chart.
Organizational Structure
Management Roles and Responsibilities
Management of the Mine Waste Technology Program (MWTP) is specified in the Interagency Agreement. The roles and responsibilities of each organization represented are described below. The MWTP organizational chart is presented in Figure 1.
U.S. Environmental Protection Agency
The Director of the National Risk Management Research Laboratory (NRMRL) in Cincinnati, Ohio, is the principal U.S. Environmental Protection Agency Office of Research and Development representative on the Interagency Agreement Management committee. NRMRL personnel are responsible for management oversight of technical direction, quality assurance, budget, schedule, and scope.
U.S. Department of Energy
The Director of the National Energy Technology Laboratory (NETL) is the principal U.S. Department of Energy (DOE) representative on the Interagency Agreement Management committee. NETL personnel provide contract oversight for the MWTP. MSE Technology Applications, Inc. (MSE) is responsible to NETL for adherence to environmental, safety and health requirements; regulatory requirements; National Environmental Protection Act requirements, and conduct of operations of all projects.
MSE Technology Applications, Inc.
MSE, under contract with DOE, is the principal performing contractor for MWTP. The MWTP Program Manager is the point of contact for all MWTP activities. The Program Manager is responsible for program management and coordination, program status reporting, funds distribution, and communications.
An MSE project manager has been assigned to each MWTP project and is responsible to the MWTP Program Manager for overall project direction, control, and coordination. Each project manager is responsible for implementing the project within the approved scope, schedule, and cost. MSE also provides all staff necessary for completing Activities II, III and V and oversight of Activities III, IV, and VI.
Montana Tech of the University of Montana
As a subcontractor to MSE, Montana Tech of the University of Montana is responsible to the MWTP Program Manager for all work performed under Activities I, IV, and VI. The responsibility for overall project direction, control, and coordination of the work to be completed by Montana Tech is assigned to the MWTP Montana Tech Project Manager.
Technical Integration Committee
The Technical Integration Committee (TIC) serves several purposes in the MWTP organization: 1) TIC reviews new proposals and ranks them at a meeting held in Butte, Montana; 2) it reviews progress in meeting the goals of the MWTP and alerts the Interagency Agreement Management Committee to pertinent technical concerns; 3) it provides information on the needs and requirements of the entire mining waste technology user community; and 4) it assists with evaluating technology demonstrations as well as technology transfer. This committee is comprised of representatives from both the public and private sectors.
Looking Ahead to FY 04
During FY04, the following additional projects will be funded under Activity III of the MWTP.
Project 28—Mine Site Telemetry
This project will evaluate the performance of a fuel cell supplied by the DOE National Energy Technology Laboratory as the power source for instrumentation and equipment at a remote mine site.
Project 41—Update of Case Studies
This project will complete three case studies on mine sites initially done using funding from the EPA Superfund Innovative Technology Evaluation Program. The work will include comment incorporation from reviewers as well as updated information about each site. The three sites profiled in the original document included: Gilt Edge Mine in South Dakota; the Leviathan Mine in California; and the Golden Sunlight Mine in Montana.
Project 42—Physical Solutions for Acid Mine Drainage at Remote Sites
This project will evaluate a technology for the removal of heavy metals from acid mine drainage in the Ten Mile Creek area of Montana in support of EPA Region 8. The FY04 scope includes bench-scale evaluations of simple technologies for treating up to five different waters, the combination of three waters from the Ten Mile Creek area, as well as one water from the ASARCO smelter in Montana City, Montana.
Project 43—Thallium Removal from Mine Waste Waters
This project will further evaluate the thallium removal technology developed under Activity IV, Project 12 of the MWTP. The purpose of the evaluation is to further develop the technology, particularly the engineering aspects. A bench-scale demonstration is planned. If successful, the technology may eventually be scaled-up and demonstrated at a pilot-scale level in the field.
Project 44—Remediation of Underground Mines Using Source Control/Passive Technologies
This project will use a combination of two technologies to accomplish the remediation of an underground mine system. A source control (grouting) technology will be used to reduce the flow in the underground mine workings. A second, passive water treatment technology will be used to treat residual water discharging from the adit. The combination of the technologies is expected to increase the efficiency, longevity, and decrease the cost to operate the passive treatment system.
Project 45—Microbial and Geochemical Responses in Acid Producing Mine Tailings
This project will evaluate, at laboratory scale, the geochemical properties of mine tailings when microbes are used as the treatment technology. This project builds on the MWTP experience using sulfate-reducing bacteria and other microbes to treat AMD but focuses on the mineral forms that result from the microbial action.
Project 46—Cyanide Heap Biological Detoxification, Phase II
This demonstration will be conducted at the Gold Acres Heap Leach Pad located at Placer Dome’s Cortez Gold Mine in Crescent Valley, Nevada. The biological technology owned by Whitlock & Associates of Spearfish, South Dakota, will be used to destroy the cyanide present. The effect of the technology on heavy metals of concern will also be monitored. Column studies will be performed before application of the technology in the field.
Similarly, during FY04, the following new Montana Tech of the University of Montana Projects (Activity IV) will be funded.
Project 30—Berkeley Pit Limnocorrals
Limnocorrals have been used for about 40 years for experimental studies in lakes when it is necessary to test biological, physical, and chemical properties in situ while varying an aspect of the ecosystem on a small scale to determine the outcome. This project will test bioremediation potential in situ using limnocorrals with nitrification and inoculation with the algae as variables.
Project 31—Modified Ferrihydrite for Enhanced Removal of Arsenic from Mine Wastewater
The purpose of this study is to investigate the adsorption characteristics of ferri-oxyhydroxide (ferrihydrite) and aluminum-modified ferrihydrite for removal of arsenate and arsenite species under various conditions that vary with respect to the iron/arsenic ratio, initial arsenic concentration, arsenic valence (III and/or V), aluminum content in the aluminum-modified ferrihydrite, and pH. The relative stability of the final products will be determined and compared to products from unmodified ferrihydrite. Stability testing will be performed at elevated temperatures to accelerate crystallization kinetics and aging characteristics of ferrihydrite, aluminum-modified ferrihydrite, arsenic loaded ferrihydrite, and arsenic loaded aluminum-modified ferrihydrite solids.
Project 32—Geochemistry and Isotopic Composition of H2S-Rich Water in Flooded Underground Mine Workings, Butte, Montana
The purpose of this study will be to collect water samples from Butte's West Camp for comprehensive chemical and isotopic analysis and to combine these results with geochemical modeling to more fully understand the processes that control the geochemistry of the West Camp mine waters in Butte, Montana.
Project 33—CALPUFF Modeling of Copper Smelter Emissions
The goal of this project is to use advanced features of the CALPUFF modeling system to study the impact of the Anaconda smelter plume throughout the region. The project will be the first of its kind to use the CALPUFF modeling system to simulate impact from the Anaconda smelter stack. The three primary objectives of the project are: 1) to predict potential hotspots of contamination on the terrain from short- and long-range transport of the smelter plume; 2) to compare modeled hotspots with existing soil data; and 3) to identify sites that may warrant further investigation and remediation.
Project 34—Passive Remediation of Sulfide Wastes Through Utilization of Composite Covers, Lime, and Controlled Oxygen Diffusion: A Study of Diffusion Rates Through Composite Covers of Varying Saturation
Caps and covers are frequently prescribed to limit the access of oxygen and water to sulfide waste materials in an effort to limit the future production of acid rock drainage. The range of capping alternatives presently employed or being proposed varies widely. The objective of this research is to recreate, in diffusion cells, sample capping scenarios for the mine waste closure of potentially acid generating materials with lime as an amendment. The cell will then be used to measure oxygen flux under a scale of saturation conditions that would accurately describe the oxygen diffusion through the capping alternatives presently being prescribed in the field.
Activities
Descriptions, Accomplishments, and Future Direction
This section describes the Mine Waste Technology Program (MWTP) Activities I through VI and includes project descriptions, major project accomplishments during fiscal 2003, and future project direction.
Activity I Overview—Issues Identification
This activity focuses on documenting mine waste technical issues and identifying innovative treatment technologies. Issues and technologies are screened and prioritized in volumes related to a specific mine waste problem/market.
Following completion of a volume, appendices are prepared. Each appendix links a candidate technology with a specific site where such a technology might be applied. The technology/site combinations are then screened and ranked.
Technical Issue Status
The status of the volume documents approved for development includes:
- Volume 1, Mobile Toxic Constituents—Water and Acid Generation, complete.
- Appendix A–Remote Mine Site, complete;
- Appendix B–Grouting, complete; and
- Appendix C–Sulfate-Reducing Bacteria, complete.
- Volume 2, Mobile Toxic Constituent—Air, complete.
- Volume 3, Cyanide, complete.
- Appendix A–Biocyanide, complete.
- Volume 4, Nitrate, complete.
- Volume 5, Arsenic, complete.
- Volumes 1-5 Summary Report, complete.
- Volume 6, Pyrite, complete.
- Volume 7, Selenium, complete.
- Volume 8, Thallium, complete.
- Volume 9, Pit Lakes, in progress.
- Volume 10, Mercury, complete.
These documents can be reviewed at the web site, http://www.epa.gov/ORD/NRMRL/std/mtb/.
Activity II Overview—Quality Assurance
The objective of this activity is to provide support to individual MWTP projects by ensuring all data generated is legally and technically defensible and that it supports the achievement of individual project objectives. The primary means of carrying out this activity is the Quality Assurance Project Plan (QAPP), which is written for each project and approved by the U.S. Environmental Protection Agency (EPA) prior to data collection. This plan specifies the quality requirements the data must meet, states the project objectives, describes all sampling and measurement activities, and contains standard operating procedures, when applicable. The QAPPs are reviewed by the EPA-National Risk Management Research Laboratory (NRMRL) QA Manager and EPA-NRMRL Project Manager. All comments are addressed, and the document is approved prior to data collection. Other functions of this activity include assessing projects, validating data, implementing corrective action, and reporting to project management.
The EPA approved the MWTP Quality Management Plan in 200l. The MWTP Quality Management Plan is updated annually. The EPA-NRMRL assesses the MWTP Quality System every 3 years and performs one or more technical system reviews annually.
Activity IV Overview—Bench-Scale Testing
The objective of this activity is to develop, qualify, and screen techniques that show promise for cost-effective remediation of mine waste. The most promising and innovative techniques will undergo bench- or pilot-scale evaluations and applicability studies to provide an important first step to full-scale field demonstrations. Each experiment is assigned as an approved project with specific goals, budget, schedule, and principal team members.
Activity IV, Projects 22 and 26: Organic Matter Degradation Rate in a Sulfate Reducing Wetland, Phases I and II
Project Overview
The primary objectives for this project were to determine the
organic matter decay rate in sulfate reducing wetlands and improve
the understanding of how natural wetlands function in metals-contaminated
regions. The biodegradable organic matter serves as an indirect
carbon and energy source for sulfate reducing bacteria that convert
sulfate in the acid mine drainage to sulfide and bicarbonate,
which precipitate heavy metals and neutralize acidity. To make
quantitative predictions about long-term sulfate reduction rates
in constructed wetlands and solid-substrate bioreactors, an effective
mathematical model for the system must exist. Sulfate reduction
is needed to precipitate heavy metals, and the sulfate reduction
rate determines the rate of water treatment. The rate-limiting
step in biogenic sulfide production is organic matter degradation.
A first order rate coefficient and quantity of organic matter
are needed to predict the organic matter replenishment interval
that will keep the treatment system operating properly.
Technology Description
Field tests were run in a constructed wetland at the Upper Blackfoot
Mining Complex owned by ASARCO near Lincoln, Montana. The rate
coefficient was measured by burying dialysis bags made of regenerated
cellulose containing compost in a constructed wetland treating
acid mine drainage at the Upper Blackfoot Mining Complex. For
the laboratory investigation, two reactors (duplicate experiments)
were filled with mushroom compost and solution containing 50?milligrams
iron per liter and 500 milligrams SO42 per liter and kept in an
incubator in a laboratory at Montana Tech. Both total organic
carbon (TOC) and chemical oxygen demand (COD) were measured over
time in samples from the field wetland and laboratory reactors.
Other parameters measured included percent volatile solids, carbohydrates,
and nonacid soluble matter.
Status
The preliminary results of the 22-month experiment indicated that
neither COD nor TOC, measured as milligrams per gram (mg/g) dry
compost, changed significantly over the monitoring period, as
shown in Figures 23 and 24. Mass balance calculations indicated
that the total solids mass, TOC mass, and COD mass of the compost
all decreased by about 30%. Preliminary statistical analysis was
completed to determine if the COD concentrations of the final
samples differed from the COD concentrations of the initial samples.
The 95% confidence interval about the mean of the original compost
samples minus the mean of the final compost samples was –163
to +131 milligrams COD per dry compost; thus, it was concluded
that the COD of the compost did not apparently change significantly
during the laboratory experiment. Similarly, for TOC, the 95%
confidence interval about the mean of the original compost samples
minus the mean of the final compost samples was –19.5 to
–6.1 mg TOC per gram dry compost. The statistical analysis
appears to suggest that the TOC concentrations of the compost
samples increased during the laboratory experiment: however, if
the statistical comparison was made using the next-to-last samples
instead of the final samples, there would have been no significant
change in the compost TOC concentration. Compost samples placed
in the operating treatment wetland also experienced no significant
change in COD or TOC concentrations over a 12-month period.
There is no mechanistic explanation for TOC concentrations increasing or COD concentrations not decreasing. The most plausible explanations for the possible increase in TOC concentrations and the lack of decrease of COD concentrations are variability among samples and variability among analytical batches. There was no evidence of inaccuracy due to analytical errors in the performance of COD and TOC analyses. Further detailed discussions will be included in the final report. Field and laboratory testing was completed for Phase I and II of this project with the final report expected to be completed in FY04.
Figure 23. COD concentrations of reactor samples and field samples
in milligrams COD per gram dry compost over time. The error bars
are ± one standard deviation.
Figure 24. TOC concentrations of reactor samples and field samples
in milligrams TOC per gram dry compost over time. The error bars
are ± one standard deviation
Activity IV, Project 23: Sulfate Removal Technology Development
Project Overview
Numerous mine waters and process effluent waters contain elevated
concentrations of sulfate above the Primary Drinking Water Standard
(500 milligrams per liter) or the Secondary Drinking Water Standard
(250 milligrams per liter). The objective of the sulfate removal
technology project was to investigate the use of compound precipitation
to remove sulfate through the formation of a solid phase and to
investigate the possibility of reducing sulfate to sulfide on
a metallic surface (with subsequent precipitation of a metal sulfide).
A limited number of technologies are presently used for removing
sulfate from wastewater such as bioreduction of sulfate to sulfide
and membrane exclusion. These technologies have several disadvantages
in that they are relatively expensive to operate, require specialized
equipment, require long residence time reactors (bioreduction),
high pressure (membrane processes like reverse osmosis and nano-filtration),
and have difficult solid/liquid separations and membrane fouling
problems.
Technology Description
Two technological approaches for lowering sulfate were investigated for this project including precipitation of sulfate bearing compounds and electrochemical metal reduction of sulfate. The goal of the experimental study was to achieve a sulfate concentration of less than 250 milligrams per liter.
Status
The project final report is in the final stages of review; however,
testing and data analysis was completed to investigate both the
compound precipitation and electrochemical metal reduction methods
for removing sulfate from wastewater. Results from initial geochemical
modeling and literature reviews identified Alunite and Ettringite
as possible compounds for the reduction of sulfate using the compound
precipitation method. After preliminary scoping experiments were
performed, Ettringite was selected for further detailed study.
The preliminary tests showed that the important variables for
the formation of Ettringite were aluminum concentration, calcium
hydroxide concentration, and time of contact. The system was then
investigated using a ½ replicate of a 24 factorial experimental
design to delineate the importance of each of four selected variables.
The ½ replicate of a 24 factorial experimental design is
a one-half replica study (for four variables) and requires eight
experiments.
The design matrix studies illustrated that sulfate can be effectively lowered to the goal level in reasonable residence times. During the matrix experimental design studies, effective SO4 removal was achieved not only for high SO4 bearing solutions (near 5 g/L) but also for low SO4 bearing solutions (near 0.4 g/L). Regression equations generated from this investigation demonstrated that SO4 removal is a rather complex precipitation process that depends significantly on various variables including the initial SO4 concentration, amounts of sodium aluminate and hydrated lime, and various binary interaction parameters, and in some cases residence time. The experimental conditions that produce effective SO4 removal were verified by equilibrium modeling. In addition, four different wastewaters containing different levels of sulfate were treated by compound precipitation. The experimental results showed that sulfate concentrations were reduced below the goal limit of <250 milligrams per liter for all the treated waters.
On the other hand, based on the electrochemical experiments, it is clear that electrochemical metal reduction of sulfate to sulfide is not an appropriate technology for controlling sulfate concentrations in acid mine drainage or other effluent discharge waters. Even though thermodynamic calculations predict that sulfate should be reduced by the potentials established in a solution by the presence of elemental iron, the results of the electrochemical reduction experiments showed that sulfate reduction was unsuccessful. Further test work also demonstrated that sulfate cannot be reduced to sulfide or bisulfide even on a platinum surface. Other investigators have proposed that this effect can be explained by the metastability of sulfate, i.e., kinetically the reduction of sulfate to form the thermodynamically favored equilibrium species (sulfide or bisulfide) is very slow. In this regard, precipitation (i.e., Ettringite precipitation) would be a better treatment technology. The final report will be finalized and completed in early FY04.
Activity IV, Project 24: Algal Bioremediation of the Berkeley Pit Lake System–Phase III
Project Overview
The Berkeley Pit Lake is a former open-pit copper mine that operated
between 1955 and 1982. In 1982, the mine’s dewatering pumps
were shutoff, and the pit began filling with acidic water, which
is currently rising at a rate of about 4 meters (m) per year.
The Berkeley Pit Lake is approximately 542 m deep and 1.8 kilometers
(km) across. In 1984, the Berkeley Pit was designated as a CERCLA
Superfund site by the U.S. Environmental Protection Agency (EPA).
Other important aspects of the Berkeley Pit Lake include low acidic
pH values (pH 2.5 to 3.0) and high concentrations of various heavy
metals. Previous and ongoing Mine Waste Technology Program research
has been investigating the intricacies of the microbial ecology
of the Berkeley Pit Lake system such as the diversity of algae,
protistans, fungi, and bacteria that inhabit the pit lake.
Technology Description
This project was to further investigate some of the previously
isolated extremophiles (specifically algae) from the Berkeley
Pit Lake system that may be used as a potential solution for bioremediation.
More specifically, the project objectives were as follows: 1)
to evaluate the bioremediative potential of the four most rapidly
growing species in the Berkeley Pit Lake System; 2) to determine
which combination of nutrients will stimulate growth of the best
bioremediator of the four isolated species; 3) to determine a
temperature profile for the four species to determine their optimal
growth temperature; 4) to continue to isolate organisms and determine
their bioremediative potential; and 5) monitor algal and bacterial
counts from a profile of Pit Lake System waters.
Status
Applicable laboratory testing and data analysis is complete for
this project, and the final report is being prepared, which is
expected to be finished early FY04. Various data collection activities
included separating bacteria from algae by washing through a filter
and centrifugation and determining metal/element uptake potential
by measuring dissolved metal concentrations before and after adding
microorganisms to Berkeley Pit Lake water.
Algae isolated from the Berkeley Pit Lake, maintained in culture in the Montana Tech of the University of Montana Microbiology Laboratory, were used to obtain uni-algal axenic cultures to investigate metals removal capacity. Two algal species were used: Chlamydomonas acidophila Negoro and Chromulina freiburgensis Dofl. A total of two types of high-density cultures were obtained from the uni-algal cultures of Chlamydomonas acidophila and Chromulina freiburgensis, and uni-algal cultures of the same species but containing bacteria. Aspirator bottles containing Modified Acid Medium (MAM) were inoculated with Chromulina freiburgensis and Chlamydomonas acidophila and incubated in the growth chamber. Population levels and the purity of cultures were verified by counting the algae and the incidental bacteria. As a result, four types of high-density cultures were obtained as follows: 1) pure (axenic) Chromulina freiburgensis in MAM; 2) Chromulina freiburgensis and associated bacteria; 3) pure (axenic) Chlamydomonas acidophila; and 4) Chlamydomonas acidophila and associated bacteria.
The experiment was designed to determine if any difference may exist (if there is a difference) between the bioremediation capacity of the pure algal cultures and that of mixed cultures containing algae and bacteria that were exposed to Berkeley Pit water. The experimental matrix consisted of two factors (bacteria and species), each of which had two levels. The species factor was Chlamydomonas acidophila as one level and Chromulina freiburgensis as the second level, and the bacteria factor was pure algae cultures (no bacteria) as one level and mixed algae and bacteria cultures as the second level. This resulted in a randomized design with a 2-by-2-factorial treatment. The experiments carried out suggested that the various species of organisms examined that live in the Berkeley Pit lake are metal tolerant species and accumulate metals. The results of the statistical analysis revealed a significant difference between the initial and final concentration for all of the four treatments for aluminum, iron, manganese, and zinc. For copper, the statistical analysis results show a significant difference between the initial and final concentration for both Chromulina freiburgensis in pure culture and Chromulina freiburgensis with bacteria but no significant difference for Chlamydomonas acidophila in pure culture and Chlamydomonas acidophila with bacteria. The difference between the initial and final concentration of magnesium was statistically significant for Chromulina freiburgensis in pure culture and Chlamydomonas acidophila with bacteria, but not for Chromulina freiburgensis with bacteria and Chlamydomonas acidophila in pure culture. Finally, no statistically significant difference was shown for nickel for any of the four treatments except for Chromulina freiburgensis with bacteria treatment.
Based on the data collected within this experiment, it appears that when Berkeley Pit water is inoculated with Chlamydomonas acidophila a higher amount of metals is found in the filtrate fraction than with Chromulina freiburgensis. As such, it would appear that Chlamydomonas acidophila is a better remediator than Chromulina freiburgensis for most all the metals analyzed in this experiment. To evaluate the effect of bacteria on the metal concentration in the solution of Berkeley Pit water and algae, the metals concentrations were compared for solutions that contained algae in pure cultures and solutions with algae and bacteria. Probability values resulting from the statistical analysis showed that the bacteria factor does have a significant effect on the concentration of most metals in the filtrate fraction but only for copper, iron, and magnesium for the filter fraction. Thus, these results appear to reveal that a mixed algae and bacteria culture added to the Berkeley Pit filtered water can ad/absorb more metals than a culture of algae that does not contain bacteria (axenic culture). One explanation for this result could be that the surface area available with sorption sites provided by bacteria is larger than the surface area provided by algae cells.
Activity IV, Project 25: Heavy and Toxic Metal Remediation using Reductive Precipitation/Cementation
Project Overview
The main objective of this study was to develop an appropriate
technology for treating a variety of contaminated waters (i.e.,
groundwater, surface water, and acid mine water) by validating
the concept of reductive precipitation/cementation for removing
heavy metals specifically cadmium, copper, nickel, lead, and zinc.
Technology Description
Reductive precipitation consists of using elemental iron to control
the solution potential at a level that is favorable for removing
heavy metals by precipitation as metal sulfides while reductive
cementation refers to the direct electrochemical reduction of
the metal. Both removal processes were to occur simultaneously
during the treatment of heavy metal bearing waters such as acid
mine waters (i.e., Berkeley Pit Lake water). Previous studies
have demonstrated on a laboratory scale that zero valence iron
is effective in removing metals such as arsenic, selenium, thallium,
and mercury.
Status
Most of the laboratory testing was completed for this project,
and the final report is expected to be finished in FY04. A full
two-level design matrix test series using sodium sulfide as the
reagent was conducted for this investigation. Generally, the design
matrix tests consisted of eleven experiments (i.e., eight required
by the design matrix, two midpoint tests, and one without iron)
to investigate the influence of sodium sulfide, time, and pH on
removing heavy metals cadmium, copper, nickel, lead, and zinc.
Preliminary analysis of the experimental design matrix work on
pretreated Berkeley Pit Lake water revealed that the regulatory
effluent goal treatment requirements were met for all metals except
for zinc. Further testing revealed the removal of nickel and zinc
was apparently not as effective in the absence of iron. A more
in-depth evaluation and analysis of the data will be provided
in the final report.
Activity IV, Project 27: Subaqueous Oxidation of Pyrite and Stable Isotope Geochemistry of an Acidic Pit Lake
Project Overview
Subaqueous disposal of pyrite-rich mine waste is a common method
of preventing acidic mine drainage. It is reasoned that, by inundation
with water, the rate of oxygen (O2) ingress to the waste is drastically
reduced, thereby effectively stopping the pyrite oxidation reaction.
It is less widely known that pyrite can also be oxidized by dissolved
ferric iron (Fe3+). Previous laboratory experiments have shown
that if pyrite is oxidized, a significant percentage of the oxygen
molecules in the sulfate produced are inherited from atmospheric
O2. In contrast, for anaerobic pyrite oxidation, molecular oxygen
is absent, so that 100% of the oxygen atoms in the sulfate produced
must come from the water itself. The primary interest for this
research project is the Berkeley Pit Lake in Butte, Montana. The
Berkeley Pit Lake is a former open-pit copper mine that operated
between 1955 and 1982. In 1982, the mine’s dewatering pumps
were shut off, and the pit began filling with acidic water. In
1984, the Berkeley Pit was designated as a Superfund site by the
U.S. Environmental Protection Agency (EPA).
Technology Description
This research was divided into two subprojects. Subproject 1 involved
bench-scale experiments aimed at quantifying subaqueous pyrite
oxidation rates by ferric iron, using control samples of pure
pyrite, as well as actual wallrock material and water from the
Berkeley Pit Lake in Butte, Montana. Subproject 2 involved collecting
a suite of stable isotope analyses (S and O) of water and aqueous
sulfate from the Berkeley Pit Lake, waters emptying into the Berkeley
Pit Lake, and selected laboratory experiments.
The main objective of Subproject 1 was to demonstrate the potential importance of subaqueous pyrite oxidation by Fe3+, with special attention to the possible role this process plays in the generation of acid in pit lakes. The main objective of Subproject 2 was to use stable isotopes to help elucidate the primary mechanism of pyrite oxidation in the Berkeley Pit Lake (i.e., aerobic versus anaerobic).
Status
Field sampling and most laboratory testing was completed for this
project, and the final report is expected to be completed in FY04.
Preliminary analysis of the data (from bench-scale experiments
aimed at quantifying subaqueous pyrite oxidation rates of shallow
Berkeley pit water) revealed that pyrite oxidation rates in pit
water are similar to those using synthetic iron chloride solutions,
which suggests that the presence or absence of other metals does
not greatly change the pyrite oxidation rates. In addition, it
was observed that during pyrite oxidation experiments using deep
Berkeley Pit water, [under cold (5 °C) conditions], rates
of pyrite oxidation by Fe3+ were slower than using shallow pit
water under ambient temperature (20 °C) conditions.
Preliminary results of the S and O isotopic compositions of the mine waters sampled in this study show a clear evaporation trend. Samples that have undergone the greatest percent evaporation come from the shallow Berkeley Pit Lake. The deep Pit Lake and Horseshoe Bend influent waters appear to have identical isotopic signatures and indicate an intermediate degree of evaporation. Shaft waters show the least amount of evaporation and compare fairly close to the meteorological water line for average precipitation in Butte. The O-isotopic composition of sulfate in the Berkeley Pit Lake is consistent with an anaerobic pyrite oxidation model. This supports the general hypothesis that the sulfate and acid in the Berkeley pit may be derived by subaqueous oxidation of pyrite by Fe3+; however, because the isotopic relationships are very complex, it is not proof that this is the case.
Activity IV, Project 28: Effects of Plant Species and Rodents on the Sequestration and/or Movement of Mercury from Reclaimed Sites
Project Overview
Mercury has been used to amalgamate precious metals throughout
recorded history and was used extensively in the Western United
States gold fields including Montana. During the period from 1850
to 1900, it is estimated that gold mining consumed 70,000 tons
of mercury. The overall efficiency of mercury utilization/ recovery
in gold processing was low and most estimates reveal a mass loss
of mercury at least equivalent to the mass of gold recovered.
As a result of the low recovery, mercury has created a variety
of environmental concerns. A scenario for the movement of mercury
in the environment from mining wastes or from repositories is
the initial uptake and accumulation in vegetation followed by
the consumption of vegetation by herbivorous organisms.
The objective of this project was to examine this scenario by determining the uptake of mercury by selected plant species and the possible movement of mercury from plants to higher level consumers such as mice. This project examined the mercury levels in vegetation and mice associated with mercury contaminated and noncontaminated (or control) sites. Contaminated sites in Montana include the Silver Creek Drainage near Marysville, Montana, and the High Ore Creek repository near Boulder, Montana. A noncontaminated (or control) site was also included in this study.
Technology Description
Part I of this research examined the root/shoot ratios of mercury
in four commonly used reclamation species in the greenhouse as
well as from other woody and nonwoody species currently growing
on mine wastes in the Silver Creek Drainage. Part II of this research
project examined mice from a mercury contaminated mine drainage
(i.e., Silver Creek Drainage) and from noncontaminated sites (i.e.,
Ranch Site) to determine if mice represent a pathway for environmental
mercury transport. Mouse hair was used as an indicator because
mercury is readily deposited into hair and stays for a comparatively
long time. Small mammals (i.e., rodents) were used for ecological
monitoring because they are small, easy to handle, and spend their
entire life cycle within a relatively small area (usually even
within small impacted areas such as mine sites).
Status
Field investigation and laboratory testing was completed for this
project, and the final report is expected to be completed in FY04.
The preliminary results reveal that the grass species sampled,
and growing on the most contaminated site, were not accumulating
substantial amounts of mercury in either their roots or leaves.
Two tree species were also sampled: Ponderosa pine and Douglas
fir. The Ponderosa pines sampled did not accumulate mercury in
either roots or needles, but the Douglas fir trees sampled did
accumulate mercury in roots but not needles.
Two shrub species were also sampled, and a few plants of both species accumulated mercury in their roots. The repository site had very low levels of mercury in cover soil, grass roots and leaves, and in mouse hair. Hence, this repository appears to be preventing the movement of mercury into the surrounding biota.
The results also show that mice can be used as a bioindicator for potential mercury contamination. Mice from the contaminated Silver Creek Drainage and from the Ranch Site approximately 3 miles from Silver Creek accumulated mercury in their hair. Average measured mice hair mercury concentrations at Silver Creek Drainage and Ranch Site were 4.47 and 5.15 µg/g, respectively. Mice from the repository and from a more distant ranch site had much lower hair mercury levels (average of 0.81 to 0.82 µg/g) as did the cover soil at the repository. A conclusion from these results is that, to date, the repository has prevented mercury in the repository tailings from entering the mice ecosystem and that the engineering design used has effectively isolated the mercury in the tailings. Since mice are relatively easy to capture, they could be used as a relatively low cost and long term biological monitor for sites constructed to isolate mercury containing wastes.
A secondary purpose of the study was to determine the uptake of mercury by grass species grown under controlled greenhouse conditions. Four species of grass recommended for possible use as reclamation species in the Butte/Anaconda area were tested. None of the four species accumulated mercury from spiked soils (similar to the species from the contaminated field site) and appear to be suitable for revegetation on sites with elevated mercury levels.
Activity IV, Project 29: Field Monitoring and Evaluation of Reclamation Strategies of Abandoned Mine Sites in the Helena National Forest
Project Overview
The main purpose of this project was to help evaluate the effects
of previously selected remediation methods on both abandoned upland
as well as wetland mine sites. For this investigation, field tests
were completed at three reclaimed mine sites in the Helena National
Forest: the Ontario Mine, Armstrong Mine, and Upper Valley Forge
Mine. All of the sites are located west of Helena, Montana, and
south of Elliston, Montana, and State Highway 12 in the Helena
National Forest. There were two wetland sites studied at both
the Ontario Mine and the Upper Valley Forge Mine, and there were
two upland sites studied at each of the three locations. The wetland
sites are located along stream banks that had been previously
covered in mine tailings.
Recent reclamation activities conducted by the U.S. Forest Service removed the actual tailings; however, the native ground underneath appears to be still contaminated with elevated levels of metals. Typically, the sites under investigation contained reclaimed waste rock piles and reclaimed tailings piles.
Technology Description
For this investigation, the movement of contaminants across the
interface between supposed clean fill materials and the contaminated
substrates were monitored with Unibest PST-1 resin capsules. The
Unibest PST-1 resin capsule is designed to mimic plant roots and
adsorb bioavailable elements and compounds. Each of these capsules
contains thousands of resin beads charged with hydrogen (H+) and
hydroxide (OH-) ions held within a porous fabric membrane. The
mixed-bed resins act as a strong sink for ions from soil solution.
The amount of each ion adsorbed by a resin capsule during a specific
amount of time depends on the initial soil concentration of each
ion, the diffusion rate of each ion through the soil, and the
capsule surface area in contact with the soil. The contents of
the resin capsules were analyzed for dissolved arsenic, cadmium,
copper, lead, zinc, and iron. Trends in metal concentrations over
the course of the study will be evaluated and compared.
Status
Field monitoring and most of the laboratory testing were completed
for this project, and the final report is expected to be finished
in FY04. Ion resin capsules were collected and analyzed for metals
approximately every 4 weeks from June 2003 through November 2003
at each of the sites. Preliminary graphical analysis of the ion
resin capsule data (as a percentage of the initial soil concentration)
from the Upper Valley Forge wetland site is provided in Figures
25, 26, and 27. In general, the trends observed in the data collected
for the Upper Valley Forge upland and wetland sites were similar
with higher metals levels being adsorbed at the wetland sites.
The quality of metals adsorbed by the capsules in the contaminated
layer are relatively similar to the other soil/waste layers, which
appears to suggest that groundwater flowing through the site is
a source of metals being adsorbed by the resin capsules. Overall,
the effectiveness of the reclamation methods appeared to be variable
based on the information collected. At wetland sites, the reclamation
work did not appear to reduce metal movement as observed from
the high rate of metal movement into the resin capsules relative
to the initial soil concentrations. However, metal concentrations
adsorbed by the resin capsules in the upland sites were low, which
would seem to indicate the reclamation was effective in preventing
metal movement during the monitoring period.
Figure 25. Metal Adsorption Percentage at Upper Valley Forge UVF-3-1.
Figure 26. Metal Adsorption Percentage at Upper Valley Forge UVF-3-2.
Figure 27. Metal Adsorption Percentage at Upper Valley Forge UVF-3-3.
Activity V Overview—Technology Transfer
This activity consists of making technical information developed during Mine Waste Technology Program (MWTP) activities available to industry, academia, and government agencies. Tasks include preparing and distributing MWTP reports, presenting information about MWTP to various groups, publications in journals and magazines, holding Technical Integration Committee meetings, sponsoring mine waste conferences, and working to commercialize treatment technologies.
Fiscal Year Highlights
• The MWTP Annual Report was published summarizing fiscal
year accomplishments. A similar report will be published each
year.
• Several MWTP professionals appeared at various meetings to discuss the Program with interested parties. MWTP personnel attended and presented papers at many mine waste conferences, as well as mining industry meetings.
Activity VI Overview—Training and Education
Through its education and training programs, the Mine Waste Technology Program (MWTP) continues to educate graduate students in the Mine and Mineral Waste Emphasis Program, professionals, and the general public about the latest information regarding mine and mineral waste cleanup methods and research.
As a result of rapid technology and regulatory changes, professionals working in the mine- and mineral-waste areas often encounter difficulties in upgrading their knowledge and skills in these fields. In recent years, the environmental issues related to the mining and mineral industries have received widespread public, industry, and political attention. While knowledge of current research and technology is vital for dealing with mine and mineral wastes, time and costs may prevent companies from sending employees back to the college classroom.
Through traditional college coursework, short courses, workshops, conferences, and video outreach, Activity VI of MWTP educates professionals and the general public and brings the specific information being generated by bench-scale research and pilot-scale technologies to those who work in mine- and mineral-waste remediation.
Fiscal 2003 Highlights
- Montana Tech of the University of Montana (Montana Tech) took a leading role in the implementation of the Workshop on Mining Impacted Native American Lands in Reno Nevada, conducted September 9 through 11. A variety of issues were presented and discussed, including cultural issues, trust issues, specific case studies, environmental and human health, water impacts, and remediation and reclamation activities. Approximately 200 were present for the workshop with approximately 30 guest speakers.
- Hardrock Mining 2002, conducted in May 2002, was an opportunity to examine and discuss current and future environmental issues shaping the mining industry with an emphasis on case study analysis and technology verification. The U.S. Environmental Protection Agency’s (EPA) Office of Research and Development and EPA’s National Risk Management Research Laboratory (NRMRL) sponsored the 3-day event. MWTP provided funding and sponsorship. Attendees exchanged scientific information serving to enhance remediation and cleanup of both legacy and current mining wastes and to contribute to a sustainable U.S. modern mining industry. NRMRL’s Technology Transfer staff completed a CD that includes the conference materials, presentations, posters, and transcripts of plenary speakers. Call (513) 560-7804 to obtain the CD.
- The Mine Design, Operations, and Closure Conference 2003, conducted
in April 2003, continued last year's interagency cooperation. The
5-day event was cosponsored by the U.S. Forest Service; U.S. Bureau
of Land Management; Montana Department of State Lands; MSE Technology
Applications, Inc.; Haskell Environmental Research Studies Center;
several other private companies; and Montana Tech. During the conference, experts presented overviews on such topics as predictive chemical modeling for acid mine drainage, mine water quality source control, state-of-the-art containment technologies, and innovative pit reclamation. Over 150 mine operators, consultants, and professionals from the private and public sectors attended the conference. - The Mine and Mineral Waste Emphasis Program has an enrollment of 11 students with all of them receiving funding from MWTP. This is an interdisciplinary graduate program that allows students to major in their choice of a wide variety of technical disciplines while maintaining an emphasis in mining and mineral waste.
- Mine and Mineral Waste Emphasis graduate students from Montana Tech attended the Mine Design, Operations, and Closure Conference 2003 in Polson.
- Graduate students in the Mine and Mineral Waste Emphasis Program are working on projects in Activities IV.
- As part of the Native American Initiative, Montana Tech presented a variety of short courses: Mining and the Environment, Acid Rock Drainage, Mining Hydrology, and Hazwoper at Fort Belknap. Hazwoper was provided so that the Native Americans could participate in the reclamation cleanup on the mine site. An environmental learning community was set up to house the short courses and Web courses to make them accessible to Native American communities around the country. Available courses include Acid Rock Drainage, Environmental Planning, Mining and the Environment, Golf Course Planning, Trailways, Hazwoper, Hazardous Materials Management, Geographical Information Systems, Ecosystem Management, Water Resources, and Alternative and Innovative Treatment Technologies.
Future Activities
The following training and educational activities are scheduled
for 2004:
- MWTP Training and Education program will offer the Mine Design, Operations, and Closure Conference in April 2004.
- MWTP Training and Education program will participation in the Battelle Technology Conference in May 2004
- MWTP Training and Education program personnel will be on the steering committee for the Pit Lakes Conference in the fall of 2004.
Financial Summary
Total expenditures during the period October 1, 2002, through September 30, 2003, were $3,244,739, including both labor and nonlabor expense categories. Individual activity accounts are depicted on the performance graph in Figure 28.
Figure 28. Mine Waste Technology Program fiscal 2003 performance graph, costs per activity..
Completed Projects
For information on the following completed Mine Waste Technology Program projects, refer to the web site: http://www.epa.gov/ORD/NRMRL/std/mtb/mwt/.
Activity III (Demonstrations)
Project 1 Remote Mine Site
Project 2 Clay-Based Grouting
Project 4 Nitrate Removal
Project 5 Biocyanide
Project 6 Pollutant Magnet (canceled)
Project 7 Arsenic Oxidation
Project 9 Arsenic Removal
Project 10 Surface Waste Piles?Source Control
Project 11 Cyanide Heap Biological Detoxification
Project 12 Sulfate-Reducing Bacteria Reactive Wall
Project 12A Calliope Mine Internet Monitoring System
Project 13 Hydrostatic Bulkhead with Sulfate-Reducing Bacteria (canceled)
Project 14 Biological Cover
Project 16A Sulfate-Reducing Bacteria-Driven Sulfide Precipitation
Project 17 Lead Abatement
Project 18 Gas-Fed Sulfate-Reducing Bacteria Berkeley Pit Water Treatment
Project 19 Site In Situ Mercury Stabilization Technologies
Project 20 Selenium Removal/Treatment Alternatives
Project 22 Phosphate Stabilization of Mine Waste Contaminated Soils
Project 23 Revegetation of Mining Waste Using Organic Amendments and Evaluate
the Potential for Creating Attractive Nuisances for Wildlife
Project 25 Passive Arsenic Removal
Project 27 Remediating Soil and Groundwater with Organic Apatite
Project 31 Remote Autonomous Mine Monitor
Project 35 Biological Prevention of Acid Mine Drainage (Gilt Edge Mine)
Project 36 Ceramic Microfiltration System
Activity IV
Project 1 Berkeley Pit Water Treatment
Project 2 Sludge Stabilization
Project 3 Photoassisted Electron Transfer Reactions Research
Project 3A Photoassisted Electron Transfer Reactions for Metal-Complexed
Cyanide
Project 3B Photoassisted Electron Transfer Reactions for Berkeley Pit
Water
Project 4 Metal Ion Removal from Acid Mine Wastewaters by Neutral Chelating
Polymers
Project 5 Removal of Arsenic as Storable Stable Precipitates
Project 7 Berkeley Pit Innovative Technologies Project
Project 8 Pit Lake System?Characterization and Remediation for the Berkeley
Pit
Project 9 Pit Lake System?Deep Water Sediment/Pore Water Characterization
and Interactions
Project 10 Pit Lake System?Biological Survey of Berkeley Pit Water
Project 11 Pit Lake System Characterization and Remediation for Berkeley
Pit?Phase II
Project 12 An Investigation to Develop a Technology for Removing Thallium
from Mine Wastewaters
Project 13 Sulfide Complexes Formed from Mill Tailings Project
Project 14 Artificial Neural Networks as an Analysis Tool for Geochemical
Data
Project 16 Pit Lake System Characterization and Remediation for Berkeley
Pit?Phase III
Project 17 Mine Dump Reclamation Using Tickle Grass Project
Project 18 Investigation of Natural Wetlands Near Abandoned Mine Sites
Project 19 Removing Oxyanions of Arsenic and Selenium from Mine Wastewaters
Using Galvanically Enhanced Cementation Technology
Project 20 Algal Bioremediation of Berkeley Pit Water, Phase?II
Key Contacts
U.S. Environmental Protection Agency:
Roger C. Wilmoth
U.S. Environmental Protection Agency
Office of Research and Development
National Risk Management Research
Laboratory
26 W. Martin Luther King Drive
Cincinnati, OH 45268
Telephone: (513) 569-7509
Fax: (513) 569-7471
wilmoth.roger@epa.gov
U.S. Department of Energy:
Madhav Ghate
U.S. Department of Energy
National Energy Technology Laboratory
P.O. Box 880
3610 Collins Ferry Road
Morgantown, WV 26507-0880
Telephone: (304) 285-4638
Fax: (304) 285-4135
mghate@netl.doe.gov
MSE Technology Applications, Inc.:
Jeff LeFever, Program Manager
MSE Technology Applications, Inc.
P.O. Box 4078
Butte, MT 59702
Telephone: (406) 494-7358
Fax: (406) 494-7230
jlefever@mse-ta.com
Montana Tech:
Karl E. Burgher, Montana Tech MWTP
Project Manager
Montana Tech of the University of Montana
1300 West Park Street
Butte, MT 59701-8997
Telephone: (406) 496-4311
Fax: (406) 496-4116
kburgher@mtech.edu