impacts of water quality from placement of coal combustion waste

IMPACTS ON WATER QUALITY FROM

PLACEMENT OF COAL COMBUSTION WASTE

IN PENNSYLVANIA COAL MINES

Editor and contributing author: Jeff Stant, Project Director Clean Air Task Force Contributing authors: Lisa Evans, Environmental Attorney Robert Gadinski, Professional Geologist Charles Norris, Professional Geologist

July 2007

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Pennsylvania Minefill Study Clean Air Task Force, August 2007

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AUTHORS AND ACKNOWLEDGEMENTS This Report is the product of the Pennsylvania Minefill Research Project undertaken by the Clean Air Task Force. The Task Force is a nonprofit organization dedicated to restoring clean air and healthy environments through scientific research, public education and legal advocacy. Authors Jeff Stant, editor and contributing author, is the Director of the Power Plant Waste Program of the Clean Air Task Force and directed the Pennsylvania Minefill Research Project which began in 2003 and culminated in the production of this Report. Mr. Stant was the editor of this report and for the past two years has served as a primary researcher and contributing author. Mr. Stant has had extensive experience in matters pertaining to coal combustion waste management. As Executive Director of the Hoosier Environmental Council in Indiana from 1985 until 2000, Mr. Stant became a primary spokesperson for regulatory safeguards needed in CCW minefill permits in Indiana as well for national safeguards needed in the 2000 Regulatory Determination on Wastes from the Combustion of Fossil Fuels by US EPA. Mr. Stant has examined CCW disposal sites, monitoring data and regulatory requirements in numerous states. Since leaving HEC, Mr. Stant has served as a consultant to the national Citizens Coal Council, Neighbors For Neighbors in Texas and the Clean Air Task Force concerning safeguards for CCW management in coal mines in New Mexico, Indiana, Texas and West Virginia in addition to Pennsylvania. Mr. Stant has represented the environmental community in mediated discussions for rulemakings on CCW management in mines in Indiana and in Washington D.C. and was a primary advocate for the congressional authorization of the study and report in 2006 by the National Research Council, Managing Coal Combustion Residues in Mines. Lisa Evans, contributing author, is an environmental attorney who directed the Power Plant Waste Program of the Clean Air Task Force from 2000-2006. Ms. Evans conducted research and assisted in the writing and editing of this report. She is currently working as an attorney for Earthjustice and before working for the Task Force, served as an assistant regional counsel for US EPA Region I in matters pertaining to enforcement of the Resource Conservation and Recovery Act and the Comprehensive Environmental Response, Compensation and Liability Act.

Robert Gadinski, contributing author, is a professional geologist licensed in the Commonwealth of Pennsylvania. He served as the Hydrogeologist Supervisor for the Special Projects Section of the Pennsylvania Department of Environmental Protection, Northeast Regional Office located in Wilkes Barre, PA. Mr. Gadinski has worked extensively in the Anthracite Coal Region of Pennsylvania and has authored/co-authored several papers involving projects in the coal measures including the monitoring of mine pools in the region.


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Charles Norris, contributing author, is a professional geologist licensed in six states, including Pennsylvania, and is a Principal of Geo-Hydro, Inc., Denver, Colorado. Mr. Norris has worked on CCW disposal and placement policies, related mining issues, and remediation of contamination by CCW, since 1990.

In addition to assisting in the research and writing of select portions of this report, Mr. Norris and Mr. Gadinski certified the scientific assessments of impacts to sites in this report as Professional Geologists licensed by the Commonwealth of Pennsylvania.

Acknowledgements The Clean Air Task expresses its deep appreciation to Bill Hopwood and the J.M. Hopwood Charitable Trust whose generous support made the production of this report possible. We would also like to thank The Western Pennsylvania Watershed Program for its invaluable contributions of resources and logistical support for this project. The Clean Air Task Force would also like to thank the Pennsylvania Minefill Project Advisory Committee for their expert guidance, advice and internal peer review of the Report. The involvement of the Advisory Committee lead to substantial improvement of the report and was greatly appreciated. The following individuals served on this committee: John Arway Pennsylvania Fish and Boat Commission Bellefonte, PA Beverly Braverman, Esq. Mountain Watershed Association Tri-State Citizens Mining Network (Center for Coalfield Justice) Melcroft, PA Dr. Subash Chander* Department of Energy and Geo-Environmental Engineering Penn State University Park, PA R. John Dawes The Western Pennsylvania Watershed Program Alexandria, PA Dr. Robert M. East Environmental Studies Program Washington & Jefferson College Washington, PA


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Thomas Gerhard Weatherly, PA Launa Haney Post Hopwood, Inc. Washington, PA Stephen Tertel Tamaqua, PA Kurt Weist, Esq. PennFuture Harrisburg, PA Paul Ziemkiewicz, PhD WV Water Research Institute West Virginia University Morgantown, WV *The Task Force sincerely regrets the passing of Dr. Subash Chander in December, 2006. Dr. Chander generously provided advice and his insights were very helpful to the construction of this report. We miss him. In addition, the Clean Air Task Force greatly appreciates the assistance of the following persons who retrieved data, provided information, reviewed and/or edited the report or assisted in the creation of maps and graphs or presentation of data: John Melndez, Cibola International, Indianapolis, IN, for technical support, editing, presentation of data, and production of final report. Susan Green, Yourstorydigital, Flagstaff, AZ, for the correction and finalizing of site maps, and production and presentation of the final report. Lisa Graves Marcucci, Jefferson, PA, for the retrieval of data and information from Western Pennsylvania PADEP offices. W.D. Richey, Pittsburgh, PA, Professor Emeritus of Chemistry, Chatham College for additional scientific assessment and presentation of the data. Jim Gollin, Sarah Evans, Don Mottley, Denise Joines, Liza Hyatt, Martin Grams-Stant, Natalie Stant, Crystal Dobson, Dante Picciano, Steven and Patti Dreyer and Morton Gollin for their valuable assistance and support. In 2005, drafts of twelve of the site reviews included in this report were sent to the Pennsylvania Department of Environmental Protection (PADEP) for their technical


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review. The Clean Air Task Force thanks PADEP for providing detailed comments on these reviews. We appreciate the assistance of PADEP staff in discussing permit requirements and mine ash placement sites with CATF researchers and providing permits, monitoring data and other relevant documents and information to CATF from the files of six district mining offices and two regional PADEP offices. We thank the many PADEP staff members who individually assisted CATF researchers in obtaining this information. These individuals include Tim Kanai and Tammy Hanna of the Cambria/Ebensburg District Office, Keith Laslow, Roger Hornberger, Mike Menghini, Sharon Hill, Dave Williams and Janette Samay of the Pottsville District Office, John Varner, Doug Saylor and Janet Turner of the Moshannon/Phillipsburg District Office, Laurie Odenthal, Doug Stewart and David Updegrave of the Knox District Office, Joe Leone, Joe Matches, and Craig Burda of the California District Office, Thomas Kovalchuk, Scott Bradley, and Rich Krivda of the Greensburg District Office, Kim Snyder, Lisa Hanigan, and John Mellow of the Wilkes Barre Regional Office and Al Diberto of the Central Office of the PADEP in Harrisburg. The Clean Air Task Force also acknowledges the contribution of researchers Roman Kyshakevych and Henry Prellwitz to portions of the first draft of this report. The Clean Air Task Force takes responsibility for the contents of this report and will consider additional review comments for future publication or additional efforts derived from this report. PHOTOS: CD Label Steam rises from FBC culm ash being dumped in the bottom of the Springdale Pit, Schuylkill County, PA. Provided by Army for a Clean Environment, Tamaqua PA. Taken November 2003. Front Cover Ernest Mine, in Indiana County, PA. Since 1996, the dark gray coal refuse (gob) has been remined from this site and replaced with approximately 2 million tons of reddish-brown FBC gob ash from the Cambria Cogen Plant. Photo by Jeff Stant, August 2007.


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Executive Summary

All of the Departments monitoring at the numerous ash reclamation sites demonstrates no harmful components leaching into the groundwater due to ash.

An investigation of [ash placement sites in Western Pennsylvania where groundwater contamination was alleged] revealed that water contamination is resulting from acid mine drainage that existed prior to the remining and reclamation of the sites, and that this degraded water has not been further impacted by the use of coal ash.

Pennsylvania Department of Environmental Protection, Fact Sheet, Coal Ash and Dredge Sediment in Mine Reclamation, August 2003. (Emphasis added.)

For over 20 years, the Pennsylvania Department of Environmental Protection

(PADEP) has been promoting the placement of large volumes of coal combustion waste (CCW) in active and abandoned coal mines as a method of addressing acid mine drainage, increasing soil fertility and filling mine pits and voids. There is growing concern, however, that placement of CCW in mines may be contaminating groundwater and surface waters with harmful levels of toxic chemicals, including aluminum, chloride, iron, manganese, pH, sulfate, total dissolved solids and toxic levels of trace elements such as arsenic, nickel, selenium, lead, mercury, molybdenum, cadmium, copper, chromium, antimony, boron and zinc. Congressional concern about potential adverse impacts of coal ash in mines lead to the recent study of this issue by the National Academies of Science. Many have raised concerns that CCW contamination could result in water quality that is more deteriorated than the adverse conditions created by acid mine drainage.

The purpose of this report is to test PADEPs oft-repeated claim that the use of CCW in coal mine reclamation, as permitted by the PADEP under their beneficial use program, does not result in the pollution of groundwater or surface water. The report tests this claim by examining monitoring data from 15 minefill sites to determine if any degradation of groundwater or surface water has occurred. The hypothesis being tested is whether the data allow one to state definitively, as does PADEP, that the use of CCW has not caused or contributed to contamination. Even if the data are merely inconclusive, this hypothesis must be rejected and the practice of CCW minefilling, as permitted in Pennsylvania, may not be declared a proven success from the standpoint of water quality protection.

It is fair to state the hypothesis this way and to assign the burden of proof in this

manner for two reasons. First and most fundamentally is the precautionary principle, a rule of decision under which doubts are resolved against an activity that might cause harm to people or the environment and which places the burden of proof on the


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proponent of the activity to demonstrate that it is safe. Second, the hypothesis fairly states the claim being made by PADEP, which has become a focal point of the national debate over the impacts and regulation of CCW minefilling.

The thorough and detailed analyses in this report, nevertheless, allow the authors

to go further than merely rejecting the above hypothesis. Our report states affirmatively that the monitoring data indicates permitted CCW minefilling in Pennsylvania has resulted in groundwater and/or surface water contamination. The data reveal such water quality degradation at two-thirds of the mine sites analyzed in this report.

This report examines 15 coal mining permits issued by PADEP allowing the placement of CCW. To arrive at the 15 mine sites, 110 coal mining permits allowing CCW placement in the bituminous and anthracite coalfields were inspected for monitoring data. Twenty-one permits were reviewed for closer analysis on the basis of coal ash tonnage, number of monitoring points and duration of monitoring. Nineteen of these had adequate levels of information to facilitate an examination of possible impacts of CCW on groundwater quality and, in some instances, on surface water quality. Fifteen permits were chosen to review for this report because of time and resource constraints.

Detailed analysis of the 15 minefills revealed: (1) characterization of sites insufficient to establish monitoring systems that will detect pollution from ash; ( 2) inadequate numbers of groundwater and surface water monitoring points; (3) not enough baseline data; (4) insufficient frequency of data collection; (5) significant lapses in data collection; (6) analysis of monitoring samples at detection limits too high to monitor the creation of toxic conditions; (7) failure to monitor indicator parameters that would readily differentiate ash contamination from mine pollution; (8) inadequate records describing dates, quantities, and locations of ash placement; and (9) the absence of monitoring after the completion of ash placement. Despite these deficiencies, which occurred in varying degrees in all permits, substantive evidence exists of degradation of groundwater and/or surface water from CCW in two-thirds of the permits, based on rising trends in concentrations of CCW contaminants at relevant ash monitoring points. Specifically, the authors found that in 10 of the 15 minefills studied, coal ash contributed to degraded water quality. In three other cases, degradation was occurring but the data were insufficient to differentiate the causes of the degradation. For one minefill, water quality improvement occurred in some parameters as a result of gob removal and ash placement while coal ash appeared to cause degradation in other parameters, and at one mine site, water quality improvement occurred as a result of remining and ash placement. Even in these last two cases however, the authors found that post-project monitoring was far too brief to assert that water quality improvements were more than temporary.

The import of this finding goes far beyond the implications for the health of Pennsylvania waters. There is currently a national debate over the need for federal regulation of placement and disposal of CCW in mines. Central to that debate are the two key issues explored in this report. The first is the adequacy of state programs to prevent adverse environmental impacts from CCW placement. The second is the degree to which coal ash placement poses a threat to the environment.


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This debate is not a new one. The United States Environmental Protection Agency

(US EPA) expressed serious concern over CCW minefilling in its 2000 Regulatory Determination on Wastes from the Combustion of Fossil Fuels.1 US EPA specifically noted that more information was needed on minefilling practices, impacts and the ability of government oversight to ensure that human health and the environment are being adequately protected. The Agency stated:

We are aware of situations where coal combustion wastes are being placed in direct contact with ground water in both underground and surface mines. This could lead to increased releases of hazardous metal constituents as a result of minefilling. Thus if the complexities related to site-specific geology, hydrology, and waste chemistry are not taken into account when minefilling coal combustion wastes, we believe that certain minefilling practices have the potential to degrade, rather than improve, existing groundwater quality and can pose a threat to human health and the environment.2

Recognizing the importance of this debate, Congress in 2004 directed the

National Academies of Science (NAS) and its National Research Council to study the issue of coal placement in mines. The NAS Report, published in 2006, concluded that that the presence of high contaminant levels in many CCR [coal combustion residue] leachates may create human health and ecological concerns at or near some mine sites over the long term.3 The National Research Council further concluded that placement of CCW in coal mines may be a viable option only if:

(1) CCR placement is properly planned and is carried out in a manner that avoids significant adverse environmental and health impacts and (2) the regulatory process for issuing permits includes clear provision for public involvement.4

Lastly, the NRC concurred with USEPA that enforceable federal regulations were necessary to guarantee that state programs minimized such threats to health and the environment by implementing safeguards, such as sufficient monitoring, site and waste characterization, isolation measures, corrective action standards and public participation.

The authors of this report recognize that Pennsylvania, as well as other states in

the Appalachian Region, face serious environmental and public safety concerns as a result of coal mining. This legacy includes acid mine drainage, dangerous headwalls, and blighted landscapes. Yet it is also the authors opinion that the solution to these problems should not create additional, serious environmental problems that threaten future

1 U.S. Environmental Protection Agency, Regulatory Determination on Wastes from the Combustion of Fossil Fuels, 65 Federal Register 32214, May 24, 2000. 2 Id. at 32228. 3 Committee on Mine Placement of Coal Combustion Wastes, National Research Council. , Managing Coal Ash Residues in Mines. National Academies of Science, March 1, 2006 at page 1. 4 Id.


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generations. It is with this concern that this detailed analysis of Pennsylvanias minefilling program was undertaken.

PADEP Secretary Kathleen McGinty has commented, DEP has more than 20 years in mine reclamation expertise. Our policies and procedures are the best in the nation, literally the model for federal rules. 5 This report examines this model very closely and finds it lacking in several critical respects, including the failure to recognize degradation from the use of CCW, the failure to implement a program where such impacts are easily detected and the failure to prevent such degradation. It is important that the nation learn from the 20 years of CCW minefilling in Pennsylvania. Further examination of the degradation of groundwater and surface water occurring from CCW placement in Pennsylvania coal mines and of the deficiencies of the PADEP beneficial use program will inform the national debate, lead to improvements, and afford greater environmental protection in Pennsylvania, and by example, the nation.

Based on the findings of this report, the authors make the following specific

recommendations for the Pennsylvania Coal Ash Beneficial Use Program:

1. PADEP should require that accurate and thorough waste characterization is completed prior to permitting the use of coal ash in mines.

2. PADEP should require that accurate and thorough site characterization is completed prior to permitting the use of coal ash in mines. PADEP should require the integration and updating of waste and site characterizations as new information becomes available so that placement of wastes with clearly dangerous leaching potentials in specific sites is avoided, site hydrologies are understood and monitoring is adjusted to account for changes in water movement.

3. PADEP should require comprehensive and long-term water quality monitoring at all coal ash mine placement sites.

4. PADEP should include enforceable corrective action standards for coal ash parameters at monitoring points in all coal ash mine placement permits and address degradation that occurs from coal ash at mine placement sites.

5. PADEP should issue NPDES permits for mine ash placement sites that monitor and control ash contaminants in surface discharges from these sites.

6. PADEP should require financial assurance sufficient to address potential long-term water quality problems at coal ash mine placement sites.

7. PADEP should require isolation of coal ash from groundwater at all coal ash mine placement sites.

8. PADEP should update its permit system with a modern database that is better organized and more publicly accessible.

5 Statement of Kathleen A. McGinty, Secretary, Pennsylvania Department of Environmental Protection, before the House Environmental Resources and Energy Committee, April 1, 2004.


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9. PADEP should require that all coal ash placement permits in mines actually achieve a measurable beneficial result.

10. PADEP should require ecological monitoring at all coal ash mine placement sites as a condition of the permit.

11. PADEP should establish enforceable requirements for coal ash placement permits in state regulations to replace the current system of unenforceable guidance documents.

12. PADEP should conduct a statewide programmatic review of its coal ash beneficial use program to determine whether any coal ash minefills permitted by the state are posing a threat to health or the environment and reevaluate the purpose and justification for this program.

13. PADEP should establish a program to promote the safe reuse of coal ash, prior to issuing or renewing permits for coal ash minefills, and only if such safe and beneficial recycling is unavailable, permit the placement of coal ash in Pennsylvania mines with these aforementioned safeguards.

This is a very critical time in this important debate. The Office of Surface Mining

recently published in March 2007 an advanced notice of proposed rulemaking concerning placement of coal ash in mines.6 The Office of Surface Minings proposed rulemaking is purportedly a response to the National Academies of Sciences 2006 Report, yet its proposal, which recommends only minimal changes to the federal Surface Mining Control and Reclamation Act, stands in direct contravention of the National Academies directives. We hope that the conclusions of this report, in terms of the substantial degradation found at mine sites from coal ash placement, the serious deficiencies found in Pennsylvanias program and the specific recommendations articulated above, will inform this federal rulemaking so that stronger federal requirements are indeed forthcoming before additional damage occurs throughout the United States.

6 Advance Notice of Proposed Rulemaking on Placement of Coal Combustion Byproducts in Active and Abandoned Coal Mines, 72 Fed. Reg. 12026, March 14, 2007.


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CAPTION - Winter in the massive Springdale Pit portion of the Lehigh Coal and Navigation (LCN) surface mine. This pit has a capacity of 80 million cubic yards (one cubic yard of ash is roughly equivalent to one ton) which the operator has advocated filling with contaminated freshwater, brackish, and marine dredge materials, cement kiln dust, lime kiln dust and coal ash, and received a statewide General Permit from PADEP for such purposes in 2004. A permit issued in 2005 to expand ash disposal operations in this pit from 300,000 tons of ash to 1 million cubic yards of ash and dredge material annually was appealed by a local environmental group and has been returned by LCN to PADEP. This site was not studied in the report. Photo from PADEP provided by Army For a Clean Environment, Tamaqua, PA.

Pennsylvania Minefill Study Clean Air Task Force, August 2007 Introduction

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Introduction

Requests for a moratorium on the use of fly ash for reclamation, in effect, seek protection from a danger that does not exist.

Pennsylvania Joint Legislative Air and Water Pollution Control and Conservation Committee in its Report on the Use of Fly Ash in Mine Reclamation Projects, February 5, 2004

The goal of this report is to assess the monitoring data of groundwater and surface waters downgradient of coal combustion waste (CCW) mine placement sites in Pennsylvania to determine whether increases in contaminant concentrations may be attributed to CCW placement. The CCW involved is composed of fly ash and bottom ash generated by conventional pulverized coal power plants and fluidized bed combustion power plants. To understand the potential for CCW to degrade groundwater and surface waters in Pennsylvania coal mines, this report reviews research documenting environmental harm and the potential for harm from CCW (Chapter 1). Also included in Chapter 1 is a discussion of the geology and hydrology of coal mines where the CCW is being placed and the chemical makeup of the CCW minefilled in Pennsylvania. Chapter 2 describes the methodology used to examine minefill permits, explains the presentation of the data in this report and summaries the results of site examinations. The backbone of the report, Chapters 3, 4, and 5, examines groundwater and surface water monitoring data collected at 15 CCW minefills to discern trends in concentrations of contaminants and thereby measure the effects of ash on water quality. Chapters 3 through 5 address 12 CCW minefill permits in the bituminous coalfield of western Pennsylvania and three in the anthracite coalfield of eastern Pennsylvania. The manner of placement, geology and water movement at each site is discussed. A map depicts the ash placement area, direction of relevant water flow and locations of ash monitoring points for which data are examined. Concentrations of major elements, including iron, manganese and sulfates, and trace metals, primarily arsenic, selenium, cadmium, and lead, are graphed as a function of time at upgradient and downgradient ash monitoring points. Additional ash parameters such as calcium, magnesium, chloride, sodium and others are also assessed and graphed as well as major parameters such as Total Dissolved Solids, specific conductance, acidity, alkalinity and pH. Trend lines in these graphs depict increases or decreases in average concentrations of contaminants. Loading data were also analyzed and plotted at seven sites. Monitoring data for nearly all (14 of the 15) permits reviewed indicate sustained increases in contaminant concentrations downgradient of ash placement areas after that placement began. Chapter 3 describes 10 mine sites where the data indicate that degradation occurred partially if not primarily as a result of ash placement. Chapter 4 describes three sites where degradation occurred but available data were not sufficient to

Pennsylvania Minefill Study Clean Air Task Force, August 2007 Introduction

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draw conclusions regarding the impact of ash on water quality. Chapter 5 describes two CCW minefills where water quality improved, at least in part, after ash placement. Deficiencies of the Pennsylvania CCW beneficial use program became evident through the research and analysis of these mine sites. Many of these deficiencies are systemic and result from failures of the Pennsylvania regulatory program. Chapter 6 of this report discusses these deficiencies, including the failure of the Pennsylvania program to require (1) adequate waste and site characterization; (2) isolation of the waste to avoid contamination ; (3) long term, effective groundwater monitoring; (4) corrective action when degradation is discovered; and (5) sufficient financial assurance to address contamination of water resources. The researchers also discovered serious administrative deficiencies. In several cases significant data gaps in state permit files made it difficult or impossible to determine trends for ash contaminants at ash placement sites. Lastly, Chapter 7 summarizes the results and conclusions of this report and presents recommendations for improvement of the Pennsylvania coal ash minefill program. Following Chapter 7, the reader will find three useful appendices: Appendix 1, which describes the Pennsylvania regulatory scheme governing beneficial use of coal ash in mines, Appendix 2 which includes the monitoring data graphed in the figures in the site examinations in Chapters 3, 4, and 5, and Appendix 3 which includes the tabulations of monitoring points and data from the each site that are summarized in Tables 2, 3 and 4 in Chapter 2. In sum, this report presents valuable data and important recommendations concerning the placement of coal ash in mines. Yet this inquiry into the impact of CCW minefilling on Pennsylvania waters has only scratched the surface. It is the intention of the authors that this report be a beginning and not an end. It is our goal that the findings of this report launch a larger and more thorough investigation into the science, law, and policy governing this potentially damaging practice. The health of coalfield communities and their water resources depend on the open and honest assessment of the environmental impact of placing coal combustion waste in mines.


CHAPTER 1: OVERVIEW: COAL COMBUSTION WASTE AND MINEFILLING IN PENNSYLVANIA 1.1 Introduction

To understand the behavior of CCW in mines, one must consider many factors, including the behavior of CCW in other disposal environments, its chemical composition, and CCWs propensity to change over time. To understand the motivation to place CCW in mines, one must examine the relationship between abandoned mine lands (AML), acid mine drainage (AMD), waste coal plants, and the economics of waste disposal in Pennsylvania. This chapter first reviews numerous studies describing how, why, and where CCW has caused adverse environmental impacts. Next the processes by which coal ash is produced and the chemical makeup of various types of ash are described. Lastly, this chapter briefly examines the complex relationship between coal ash placement in mines, AML, AMD and waste coal plants in Pennsylvania.

1.2 Adverse environmental impacts from coal combustion waste: review of the literature The burning of coal produces large amounts of fly ash, bottom ash, boiler slag and flue gas desulfurization sludge that are collectively called coal combustion wastes or CCW. Today CCW is the second largest industrial waste stream in America, surpassed only by mining waste. As efforts to control emissions from coal combustion increase, so have the volumes of CCW. For example, the volume of CCW produced nationally increased by 30 - 40% to approximately 130 million tons annually in 2004 largely due to requirements in the Clean Air Act Amendments of 1990 to control acid rain.1 These amendments resulted in the use of emission control devices known as scrubbers that are now generating approximately 26 million tons of flue gas desulfurization sludge (scrubber sludge) annually. The recently promulgated Clean Air Interstate Rule (CAIR) and the proposed rule to control mercury are likely to increase total CCW generation further with estimates of as much as 170 million tons being generated annually by 2015.2 The disposal of CCW has caused a variety of environmental problems particularly to soils and waters, due to an extreme pH and high concentrations of soluble salts, trace metals and other pollutants that leach from different CCWs.

Coal and CCW have been analyzed and characterized by a number of researchers. The composition of coal and coal combustion wastes varies widely. According to Block and

1 Degeare, Truett, U.S. Environmental Protection Agency, Office of Solid Waste. Overview of U.S. Environmental Protection Agency Coal Combustion Waste (CCW) Mine Fill Issues. Undated. http://www.mcrcc.osmre.gov/PDF/Forums/CCB3/5-1.pdf 2 U.S. EPA, Clean Air Markets Division. Memorandum to the Docket entitled Economic and Energy Analysis for the Proposed Interstate Air Quality Rulemaking. January 28, 2004


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Dams (1976), the composition of fly ash is significantly different from the original coal composition. For example, in comparison to coal, fly ash is relatively enriched in elements such as chlorine, copper, zinc, arsenic, selenium, and mercury (Block and Dams, 1976). According to Carlson and Adriano (1993), fly ash is also enriched in boron, strontium, molybdenum, sulfur, and calcium. Trace elements in the ash are concentrated in the smaller ash particle sizes. In a pilot study by the Electric Power Research Institute (1983), chemical analysis of coal, bottom ash, and fly ash from a southwest U.S. power plant burning southwestern subbituminous coal revealed large quantitative differences in elemental concentrations of the three materials: Aluminum Arsenic Barium Chromium Iron Magnesium Lead Silicon

(ppm) (ppb) (ppm) (ppm) (ppm) (ppm) (ppb) (ppm)

Coal 29100 7100 71.8 6.1 5130 1130 11000 50200

Bottom Ash 142000 24100 2830 29 28100 4640 23000 260000

Fly Ash 144000 32750 3110 31 24800 5260 51500 258000

A quantitative evaluation of the mobilization of trace metals from coal-burning power stations in Europe, including stack emissions and the quantities retained by the electrostatic filters, and thus present in the ash residue, was completed by G. Bignoli (Bignoli, 1989). Bignoli notes that modern electrostatic filters can filter out 99.8% of particulate matter and thus the environmental impact of most of the metals from coal-burning power plants will be due mostly to the potential releases from solid wastes. (Sabbioni, Goetz and Bignoli, 1984) Analyses of trace metals present in the coal revealed that of the total mobilization of these metals in the combustion process the great majority of the metals were retained in the solid waste and only a very small percent were present in the atmospheric stack emissions. For example, for trace metals, arsenic, cadmium, chromium, lead, antimomy and selenium, 97%, 97.2%, 99%, 97.5%, 97.7% and 91.5% of the total mobilization of each of these metals, respectively, was retained and concentrated in the coal ash. Vorre (1986) has described the nature of mineral matter in coal. This matter includes the minerals present in the original plants that were altered over time to produce coal. Geologic events such as subsidence and volcanic eruptions provided additional inorganic material. These biological and geologic processes contributed to the formation of coals each with their own signature suite of minerals. The mineral and trace element content of CCW can vary substantially depending on the locations of parent coals within different coal basins, different coal seams within the same basin, and different locations within single coal seams. Using the Lower Kittanning Coal seam in western Pennsylvania, Rimmer and Davis (1986) analyzed the physical, chemical and biological processes that affected the mineral composition of coals. The Lower Kittanning Coal seam demonstrates lateral variations in mineral compositions that


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were related to the depositional environments.3 Research by Lindahl and Finkelman (1986) and Harvey and Ruch (1986) support the variability model of the mineral content within and between coal seams and between regional basins. For example, the mean concentrations of lead, chromium, nickel, and arsenic are three to five times higher in Appalachian and Illinois Basin coals than in coals of the Rocky Mountains and Northern Plains. Numerous researchers have documented adverse environmental impacts caused by CCW to groundwater4 and surface waters, plants, aquatic life, and other organisms. Carlson and Adriano (1980) maintain that the major environmental impacts of CCW include: leaching of potentially toxic substances into soils, groundwater and surface waters; hindering effects on plant communities; and the accumulation of toxic elements in the food chain. Adriano et al. (1980), Elseewi et al. (1980), Phung et al. (1979), and Menon et al. (1990) analyzed the chemical and physical composition of fly ash under various experimental conditions to determine the environmental impact of inorganic constituents at disposal sites, such as the release of trace elements in water and treated soils. Sandhu et al. (1993) specifically studied the leaching of nickel, cadmium, chromium, and arsenic from coal ash impoundments of different ages. The general conclusion indicated that leaching produces a measurable release of metals into the environment from both old and new ash deposits: [A]sh depositsweathered and leached for over 10 years, yet still may provide a source of metal contamination to infiltrating water. Thus, ash disposal basins may be potential sources of ground water contamination for many years after ash deposition has ceased Sandhu et al. (1993). Researchers such as Rowe et al. (2002) documented the negative effect of coal combustion waste on the physiology, morphology and behavior of aquatic organisms and the health of aquatic ecosystems. According to Rowe et al (2002), the release of CCR [coal combustion residues such as fly ash] into aquatic systems has generally been associated with deleterious environmental effects. A large number of metals and trace elements are present in CCR, some of which are rapidly accumulated to high concentrations in aquatic organisms. Moreover, a variety of biological responses have been observed in organisms following exposure to and accumulation of CCR-related contaminants. In some vertebrates and invertebrates, CCR exposure has led to numerous histopathological, behavioral and physiological (reproductive, energetic and edocrinological) effects. 5

3 For example, high pyrite concentrations occurred in areas where the overlying shale indicated brackish, swamp-like, anoxic conditions. High quartz content in the northern part of the coal seam coincided with a source area where quartz was transported into the swamp by water and/or air from a topographic high area. 4 Groundwater is particularly important because half of the population of the United States relies on groundwater as its source of potable water either through public or domestic supplies (Solley et al., 1998). 5 Rowe et al. (2001) studied the adverse impact of trace metals from CCW on the standard metabolic rate of crayfish (Procambarus acutus). Other researchers such as Hopkins et al. (2000) studied the detrimental impact of trace elements on lake chubsuckers (Erimyzon sucetta). Fish exposed to lake sediments polluted with coal ash exhibited substantial decreases in growth and severe fin erosion.


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Lemly (1999) found that selenium leaching from coal ash landfills posed a great danger to fish populations and documented the elimination of a diverse fish population at Belews Lake, North Carolina from such contamination. Rowe et al. (2000) studied the effects on southern toads living in an environment polluted by coal ash concluding that major reductions occurred in local populations because less food algae could survive in the polluted water and the toxicity of coal ash trace elements in the sediments and surviving food algae killed larval toads. The study suggests that the widespread practice of disposing of coal ash in open aquatic basins may result in sink habitats for some amphibian populations. Cherry (2000) and coworkers, after evaluating the level of toxicity at 32 CCW sites throughout the world, concluded that coal combustion wastes have adverse impacts on ecosystems. Namely, trace elements and other constituents such as sulfates, chlorides, sodium, boron, manganese, iron, selenium, arsenic, lead, chromium, nickel, copper and zinc leach from CCW ash particle surfaces at toxic levels into groundwater and surface water and threaten human and aquatic life. Elseewi et al. (1980) maintain that solutions from fly ash are mostly alkaline, have a high salt content primarily due to the dissolution of Ca2+ and OH- ions, and contain an elevated concentration of boron that may be toxic to plants. According to Adriano et al. (1980), coal ash usually is not suitable for agricultural uses due to the high cost of handling and transportation from the source, very low C [carbon] and N [nitrogen] contents, and usually high pH and toxic B [boron] contents. Thus, if lands are to be used for fly ash disposal purposes, application rates should be balanced between environmental impacts and economics of waste disposal. Massive applications are usually associated with adverse effects to soils and growing plants. There has been very little research undertaken on the environmental impacts of organic constituents in CCW. Researchers have long known that coal fly ashes contain a number of polyaromatic hydrocarbons (PAHs), (Griest and Guerin, 1979) (Hanson et al, 1983, citing Sucre et al, 1979) (Bennett et al, 1979) (Hanson et al, 1979, 1980 & 1981). Examples of these PAHs include naphthalene, acenaphthylene, anthracene, dibenzofuran, fluorene, and fluoranthene. A number of the PAHs in CCW are toxic, mutagenic and/or carcinogenic in laboratory studies. Their bioaccumulation appears to be limited due to metabolism. The metabolism itself, however, may produce oxidation damage in tissues and breakdown products that are more mutagenic than their precursors. Researchers have documented that fly ashes from both pulverized coal combustion and fluidized bed combustion contain PAHs that readily cause bacteria to mutate, (Hanson et al., 1983, citing Chrisp et al, 1978, Fisher et al, 1979, Kubitschek and Haugen, 1980, Clark and Hobbs, 1980, Hill et al, 1981, and Wei et al, 1982). Hansen et al, 1983 documented that treatment of FBC fly ash with N2O4 increased its mutagenic potency by as much as 3200 times on a laboratory strain of salmonella bacteria. They concluded that potent, direct acting mutagens such as dinitropyrenes and dinitrofluoranthenes in fly ash from fluidized bed combustion power plants might be products of reactions between PAHs in the ash with nitrogen oxides in combustion gases. However, Harrison et al, 1986, concluded that the concentrations of PAHs detected in fly ash probably would not pose an environmental hazard, although they acknowledged difficulties in their ability to detect and measure


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PAHs in the fly ash. Griest and Guerin, 1979, concluded similarly that PAHs adhere strongly to ash, making analysis of their quantities and types in CCW difficult. In its Report to Congress on Wastes from the Combustion of Fossil Fuels, (March, 1999), the US EPA cited data collected by the Electric Power Research Institute in 1997 showing that coburning of petroleum coke wastes, coal gasification wastes, mixed plastics, tire-derived fuels and other organic wastes with coal generates CCW with detectable levels of benzene, chlorobenzene, cyanide, dioxins, furans, PCBs, chlorophenol, and polycyclic aromatic hydrocarbons. Despite documentation of the existence of harmful organics in CCW, monitoring for organics in groundwater and surface water surrounding CCW sites is extremely rare. Thus little is known about actual impacts to the environment from organic compounds in CCW. Although the US EPA exempted CCW from hazardous waste regulatory classification in its May 2000 Regulatory Determination on Waste from the Combustion of Fossil Fuels, it documented concerns in the Determination about the potential adverse impacts from placement of CCW in coal mines.6 US EPA concluded that safeguards were likely needed to prevent adverse impacts on water quality. US EPA also found that more research and information addressing the impacts to water quality and the environment from minefilling is needed to determine the nature of these safeguards. 1.3 Pennsylvania coalfield geology Coals are technically not classified as rocks but as fossils composed of compacted plant remains. The sedimentary rock types found with coals in the bituminous coalfields include conglo-merate, sandstone, siltstone, shale, claystone, limestone and coal. Most of these rocks are composed of mineral grains locked together by some cement, usually calcite, quartz, or clay. The bituminous coalfield in Pennsylvania covers most of the western half of the state, eastward to the Allegheny Front. This area is known as the Allegheny Plateau physiographic province and is subdivided into the Pittsburgh Low Plateau, Pittsburgh High Plateau, Allegheny Mountain, and Mountainous High Plateau provinces. Its bituminous coalfield extends into Ohio and West Virginia and represents the largest bituminous coal reserve in the United States. The coal-bearing sedimentary rocks in this coalfield are of Pennsylvanian and Permian ages, 330 to 290 million years ago (mya) and 290 to 250 mya, respectively. In western Pennsylvania, almost all of these coals are included in the lower Allegheny Group of the Pennsylvanian time period. These include three major coal beds, the deepest being the Clarion, followed by the Kittanning, with the Freeport bed closest to the surface. Only one of the permits in western Pennsylvania analyzed in this report, the Hartley Strip, involved the mining of younger coal beds (from the Permian time period) not in this group. The coals in the lower Allegheny Group were formed in near-shore 6 US EPA, Regulatory Determination on Waste from the Combustion of Fossil Fuels. Final Rule. Federal Register, Volume 65, number 99, page 32213. May 22, 2000.


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marine and/or brackish conditions and contain more sulfur than younger coals. Higher sulfur coals contribute more to the AMD problem. Younger coals including those higher in the Allegheny Group were generally deposited in more fresh water, terrestrial environments, resulting in lower sulfur contents. The anthracite coalfield is found within the Ridge and Valley physiographic province of eastern Pennsylvania. This province contains most of the anthracite found in the United States. All of the numerous coal beds in the eastern Pennsylvania anthracite region have low sulfur contents due to post-depositional metamorphism (changes to rocks from heat and pressure) and generally produce lower levels of acidity than coal beds in western Pennsylvanias bituminous region. The coal and other sedimentary layers from the Pennsylvanian Period in western Pennsylvania are generally flat-lying, except for some folds or humps (anticlines) towards the eastern margin of the bituminous coalfields. Further east, the coals and rock layers in the Anthracite field show steeply pitching geometries due to a more intense folding activity closer to the collision margin between the continental plates of North Africa and North America occurring about 250 mya. Water movement through coal-bearing sedimentary rocks is affected by four major variables: (1) local rock structure; (2) ability of water to flow through different rock types; (3) topography; and (4) man-made activities. Due to higher permeabilities, certain rocks such as limestones and sandstones convey enough water to be considered aquifers. Due to high degrees of fracturing, coal veins may also be aquifers. Natural contacts between rock layers, joints, and faults are also pathways of enhanced groundwater flow. The structural tilt (a.k.a. dip) of coals and surrounding rock layers also strongly influences the rate of groundwater flow. Groundwater flow through shallow, unconfined earth above the sedimentary layers generally follows the topography. Human activities such as coal mining can greatly affect the direction and rate of groundwater flow. Coal seams mined out from deep mining can become major man-made conduits for underground water movement, known as mine pools, that can provide pathways for groundwater exit from a site at different elevations and rates than occurred at original points of discharge. Other fractures from blasting and overburden removal operations can also become man-made conduits. Furthermore when the broken up overburden or spoil from strip mining is placed back in the working pit as mining progresses, it will transmit groundwater at a much greater rate than undisturbed rock due to the greater amount of void space in this broken material. Since many surface mines in Pennsylvania have been previously mined and mining activity can change the direction and flow of groundwater, a thorough study of water movement is needed at proposed coal mine ash placement sites to develop effective monitoring systems, as groundwater behavior and the often substantial changes in that behavior from previous and proposed mining will be site specific. Understanding chemistry of the specific ash and the geochemistry of the coal mine sites in which the ash is to be placed is also an important step to predicting impacts to water


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quality that will result from minefilling. The depositional environment in which the coal or coals were formed at these sites must be understood. In the case of previously mined sites, chemical analysis not only of overburden but also of coal mine spoils and coal refuse should be undertaken when assessing the potential for acidity and other water quality impacts. Care must also be taken to calculate the net alkalinity available in coal ash that will be exposed indefinitely to this acidity and to design placement of ash that will maximize the buffering benefits of that alkalinity. Additional knowledge of the different leaching potentials for major constituents, minor metals and trace elements in the ash and surrounding mine materials when major factors such as pH and the redox environment are changing is also important to predicting results of importing large volumes of ash into coal mines. All of these geochemical variables will be very site specific and ash specific and should be addressed on a site-to-site basis. 1.4 CCW used in Pennsylvania coal mines

1.4.1. Types of CCW: Conventional Pulverized Coal Ash, Fluidized Bed Combustion Ash and Waste Coal CCW

CCW is a waste product resulting from the combustion of coal to generate electricity. Coal is composed mostly of carbon, volatiles (oxygen and hydrogen) and non-combustible materials including clay (aluminum silicates), silica (SiO2), pyrite and marcasite (FeS2), and other metallic oxides. After the coal is burned, these non-combustible components are discarded as ash or CCW. There are two types of coal ash that are the focus of this report: 1) Conventional power plant ash from a pulverized coal (PC) plant and 2) Fluidized Bed Combustion (FBC) power plant ash. Both of these coal ashes are further divided into bottom ash and fly ash. PC bottom ash and fly ash are generated from burning primarily mine run coal, and FBC bottom and fly ashes are primarily generated by burning mixtures of coal and waste coal. There are two different types of waste coal. Coal refuse or gob is waste coal originating from bituminous coal. Waste coal from anthracite coal is called culm. Waste coal consists of the impurities cleaned from mined coal to prepare it for burning. Fly ash and bottom ash are easily distinguished. Bottom ash particles are larger and heavier than fly ash particles and do not become airborne as a result of the combustion process. Thus bottom ash is generated on the grate of the boiler. Fly ash is very fine grained and becomes airborne during combustion. In PC plants, fly ash is captured by pollution control devices such as electrostatic precipitators and bag houses installed inside and adjacent to the stacks, and bottom ash is taken out of the furnace using a conveyor type of grate. Another major type of CCW, flue gas desulfurization sludge, also known as scrubber sludge, is generated by spraying lime or other highly alkaline material in a liquid or powderized state across flue gases to remove sulfur dioxide and other pollutants. Pennsylvanias beneficial use regulations exclude scrubber sludge from the definition of coal ash, (See 25 PA Code Section 287.1) and therefore do not permit its placement in coal mines under the states beneficial use program.


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The FBC ash studied in this report typically results from burning coal piles, which are comprised of waste coal and broken overburden rock (also called spoils) left in abandoned mine areas. These piles contain less than 50% coal, the remainder is composed of waste coal and spoils. In the bituminous coal field of western Pennsylvania, some previously unexcavated coal is often also mined along with the removal of the waste coal piles. The mined mixture is crushed and then injected into the furnace combustion chamber and kept airborne by heated air insuring complete burning of most of the coal. The waste material mixed with the coal is also burned if there is any coaly material in this waste rock. During the combustion process, limestone (CaCO3) is introduced into the combustion chamber and burns to form CaO (lime). The addition of lime to the FBC ash increases its alkalinity, thus improving its potential for use as AMD remediation material. Larger incombustible particles are eventually removed from the furnace as FBC bottom ash, while lighter fly ash is captured in bag filters. Because the average ash content of waste coals is two to three times higher than parent coals and because limestone is injected into the combustion process, FBC power plants produce several times more CCW per megawatt of power than PC power plants. While FBC plants produce only 8% of the total megawatts generated by all Pennsylvania coal-fired plants, FBC ash constitutes over 60% of the CCW produced by all plants.7

1.4.2. Chemical Composition of CCW An accounting of all the chemical phases of coal before and after the coal is burned can provide a better understanding of the final chemical makeup of the CCW that is being placed in Pennsylvania coal mines. The major elements in coal are carbon, hydrogen and oxygen. The hydrogen and oxygen are volatilized and escape the boiler furnace as gasses when the coal is burned. The carbon is also burned or oxidized, with the resulting heat of combustion that boils water into steam and drives electrical generators. During combustion, the carbon reacts with the oxygen in the coal and oxygen from the atmosphere to produce carbon monoxide (CO) and carbon dioxide (CO2), both of which escape as gasses. Trace amounts of carbon are left behind in fly ashes as polyaromatic hydrocarbons and other organic compounds. These compounds usually form as products of incomplete combustion when emissions cool in the flue gasses. The minor components in coal, sulfur, iron, silica, and clay are also heated, but all is not burned or oxidized. The sulfur is burned to form sulfur dioxide (SO2), which, depending on the type of combustion, can escape as gas, be collected to produce gypsum, or be left in various oxidation states in the ash. The trace metals (many of which occur in pyrite) are separated from the sulfur and occur in the resulting ash as elemental metals and oxides. The iron is usually oxidized to form iron oxide, FeO. The shaley, or boney material in coal, particularly in FBC processes, contains silica (quartz or SiO2) and clays, which are complex hydrated aluminum silicates. The water in the clays is driven off by

7 According to DOE EIA data for 2002, waste coal burning plants in Pennsylvania total 1,559.5 MW in nameplate capacity while all other coal-fired plants in Pennsylvania total 18,920.2 MW in nameplate capacity. EIA 2002 data was not available for Pennsylvanias newest waste coal facility in Seward, PA. 521 MW was used as the nameplate capacity for that plant.


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the heat of combustion, leaving aluminum oxides, and the silica does not react, initially. The small quartz grains fuse together in a process somewhat similar to the glassmaking process. During combustion in a FBC plant, limestone is added in the furnace and is burned to lime, as outlined above. This lime reacts to form gypsum, thus removing most of the sulfur dioxide from the system. Some of the lime reacts with the silica to form calcium silicates. The excess lime is incorporated into the ash, increasing alkalinity. This lime, after the ash has been placed in a mine, can react with groundwater to form a cemented ash bound together by portlandite, Ca(OH)2. Portlandite forms by hydrating lime: CaO + H20 = Ca(OH)2. The greater the amount of limestone added to the furnace in a FBC plant, the higher the alkalinity of its ash, with most FBC ashes having significantly higher alkalinity than the alkalinity in conventional PC ashes. FBC ash also contains aluminum silicates, along with fused silica. Some sulfur is incorporated into the ash as anhydrite, CaSO4. Its metals can be incorporated, or locked up in some of the silicate minerals, or they can exist as oxides and sometimes as elemental metals. Whether burned in PC or FBC plants, most metals in coal, including trace metals, are not volatilized during the burning process and remain in the ash. Their concentrations therefore increase as the coal volume reduces to ash volume, with a resulting higher metal component in coal ash than in the original coal. For example, data from the Electric Power Research Institute (1983) shows that aluminum, arsenic, chromium, magnesium, lead, and silicon have concentrations approximately five times greater in coal ash versus coal. Barium concentrations are 42 times higher in the ash than in the coal. Only detailed mineralogical analysis can determine which mineral phases of these constituents are soluble and mobile in groundwater, or fixed and relatively insoluble.

1.4.3. Analysis of coal ash chemistry in PADEP minefill permits There are two methods used to analyze coal ash being placed in Pennsylvania coal mines: a bulk chemical analysis and a leaching test. Bulk chemical analysis reports most of the constituents that make up the ash as elemental concentrations. Sulfur is reported as sulfate. The analysis makes no attempt to determine the mineral phases that contain the constituents or the stabilities of those phases in the environment. Mineral phase identification (using X-ray diffraction and X-ray fluorescence techniques) has been used for CCW characterization to a small extent and would be a good focus for future studies. A leaching test is used to determine the mobility of trace heavy metals and other metal oxides, as well as more prevalent inorganic constituents in the ash such as sulfate, chloride, and sodium. Pennsylvania requires the use of the Synthetic Precipitation Leaching Procedure (SPLP), described as Method 1312 in US EPAs Test Methods for Evaluating Solid Waste, SW-846. In the test, a set amount of the CCW, usually 100 grams, is ground to a specified particle size and placed in a container in an extraction fluid that is 20 times the amount of the ash by weight. The extraction fluid has a pH of


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4.2 Standard Units. The container is rotated end over end at 30 rotations per minute for 18 hours. The resulting fluid in the mixture, called leachate, is filtered and analyzed for dissolved concentrations of 15 metals and four other inorganic constituents. For a coal ash to be certified for placement in a Pennsylvania coal mine, the concentrations of these constituents cannot exceed maximum acceptable leachate concentrations set by the PADEP in guidelines for the beneficial use of coal ash in mines.8 Those concentrations are normally 25 times the groundwater parameter, equivalent to Pennsylvanias drinking water standard, for metals and 10 times the groundwater parameter for nonmetals. Organic constituents are not analyzed in the test. Results of these tests are regularly reported pursuant to the section of PA mining permit permits called Module 25. While this test determines the quantity of inorganic constituents that leach out of a coal ash sample under controlled laboratory conditions for short periods, it is not designed to simulate actual conditions in the coal mines where CCW is placed. The actual conditions in mines are far more geochemically complex. University researches and several federal agencies, including US EPA, Department of Energy, and the Office of Surface Mining, as well as state regulators, admit that standard leaching tests, like the SPLP, cannot adequately predict how CCW will behave in a mine or any other real-life disposal environment. Concentrations of metals and other constituents in groundwater from CCW in disposal environments are often markedly different from concentrations generated in leachate from CCW in tests such as the SPLP. These deficiencies in the bulk analysis and leaching test used by PADEP cause environmental protection advocates to fear that CCW minefilling permits in Pennsylvania are not sufficiently characterizing the potential of CCW to contaminate groundwater or pollute surface waters. (See detailed discussion of the adequacy of CCW characterization in Chapter 6, infra.)

1.4.4. Use of CCW as Alkaline Addition to treat AMD

Current regulatory programs in many eastern states allow for the treatment of AMD with alkaline materials (often lime and sometimes CCW) to effect neutralization and metal precipitation prior to discharge. Alkaline CCW is placed directly against or blended with AMD-forming rock, spoils and coal refuse to permanently treat AMD in situ. It is considered by officials in the coal and electric utility industries and some federal and state government agencies such as the PADEP to be an appropriate and economically sound alternative to conventional AMD treatment. When ash is used for alkaline addition in a Pennsylvania coal mine, the total amount of calcium in the ash (equated to calcium carbonate found in overburden rock that can neutralize acidity) is ascertained through bulk analysis to derive the net neutralization potential of the ash. This neutralization potential is then measured against the deficiency in alkalinity in overburden rock in the mine to determine the amount of ash needed to neutralize acidity in the mine, usually with an additional amount of ash to assure that enough alkalinity is being applied. However, there is no attempt to quantify the physical availability of the alkalinity in the ash to actually buffer the acidity that will be generated 8 PADEP, Certification Guidelines for Beneficial Uses of Coal Ash, 563-2112-224, BMR PGM Section II, Part 2, Subpart 24.xxxxxx


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from the spoils or coal refuse in the mine. When more pozzelanic or cementaceous CCW such as FBC ash is placed in solid configurations and not blended with the acidic materials in the mine, environmental protection advocates fear that alkalinity bound up in hardened deposits will not be available in amounts sufficient to neutralize high amounts of acidity in mines. Even worse, the CCW placement could result in the mobilization of additional metals from the ash into mine waters if the alkalinity of the ash is eventually exhausted by the AMD. An extensive four-year column leaching study by Stewart, Daniels and Zelazny (1996) found that bulk-blending alkaline eastern bituminous coal fly ash with acid-forming coal refuse might present a disposal option that could control AMD. However, they concluded, Our data clearly indicated that ash alkalinity and refuse potential acidity must be balanced to insure long term water quality protection from ash/refuse co-disposal practices and that the breakthrough of acidic leachates may take greater than five years under certain co-disposal scenarios as modeled in our study. Stewart (1996) stated that it is evident that most eastern fly ash does not contain sufficient alkalinity to be safely co-disposed with acid-forming coal refuse without addition of supplemental alkalinity. In addition, exposing ash to strong acidic leaching environments increased the leaching of potentially hazardous trace metals. The leached amounts of metals such as manganese, iron, and copper increased proportionately with the total amount of ash applied (Stewart, 1996). 1.5 CCW, AML, AMD and Waste Coal Burning in Pennsylvania

1.5.1. Historical Perspective

It has been stated Pennsylvania carries the heaviest burden of abandoned coal mines in the country.9 Serious environmental and safety problems associated with AML include water-filled pits, dangerous vertical highwalls, subsidence and drainage problems, open shafts, abandoned gob and culm piles and, of course, AMD. These problems represent the legacy of historic mining practices. Pennsylvania has been very successful over the last three decades, through SMCRA and extensive state-sponsored research, in preventing AMD from coal mining. A measure of this success is the relative rarity of AMD generation at new SMCRA-permitted mines. According to PADEP, 17% of the mining permits issued between the years 1977 and 1983 produced post-mining discharges related to AMD. That rate dropped to 2.2% for the period between 1987 and 1996.10 A large part of the success in preventing AMD in new mines can be attributed to the rigorous state program requiring pre-mining prediction of post-mining water quality. Based on that prediction, permits are customized to prevent AMD formation, or in some cases, permits are denied when prevention appears unlikely.

9 Pennsylvania General Assembly, Joint Legislative Air And Water Pollution Control and Conservation Committee, Report on a Proposed Moratorium on the use of Fly Ash in Reclamation Projects, February, 2004. 10 PADEP, Evaluation of Mining Permits Resulting in Acid Mine Drainage, 1987-1996: A Post Mortem Study, March, 1999


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Although modern surface mining permitting decisions and operational practices have largely eliminated AMD as a problem in new mines, the legacy of past practices remains. PADEP estimates that AML constitutes about 250,000 acres in Pennsylvania.11. AMD in Pennsylvania is a problem almost entirely associated with AML.12 It should be noted, however, that even in mine settings that generate large amounts of AMD, acidity, and the high levels of metals and sulfates associated with it, usually decline significantly with time. In surface mines, as mining breaks apart pyrite-bearing rocks and coals, increasing their surface area and exposure to oxygen, the acid products are leached from rocks exposed to weathering usually within 10 to 20 years (Meek, F.A. 1996). Leaching of most acidity-producing pyrites and alkalinity-producing carbonates occurs within 20 meters of the surface due to weathering (ATRI, Prediction of Water Quality at Surface Coal Mines, ATRI). Thus the degree of exposure to air is a key, if not primary, factor involved in the creation of AMD in coal mines. A study by Ziemkiewicz and Meek of eleven, 400-ton piles of acid-producing sandstone and shale in an Upshur County, WV coal mine treated with various amendments of alkaline materials found that concentrations of sulfates exiting all of the piles from AMD declined dramatically (between ~ 85-97%) over an 11-year period and that the rates of sulfate exit from the original pyrite mass in the piles were fairly constant. The studys authors concluded, It appears that gross physical phenomena, independent of pyrite forms, surface area, amendment, pH or micro properties of the rock control the rate of pyrite oxidation within relatively narrow limits. Since the rate increased with the proportion of sandstone, oxygen diffusion is the likely candidate.13 At the same time, whether in active or abandoned surface mines, pyrite oxidation near the surface of large piles of spoils or refuse produces a rind of precipitates from chemical reactions that along with the settling of the piles tends to limit oxygen exposure and therefore retard pyrite oxidation farther beneath the surface of those piles. Acid discharges from underground mines usually last longer than AMD from surface mines. However, underground mines that are below regional water tables set by creeks and rivers (below drainage mines), usually lose their acidity significantly faster than underground mines above the water table. This is because the pyrite reacts at much slower rates and produces only small amounts of acid when left in more anaerobic conditions underwater in flooded underground mines (Evangelou 1995, Fennemore et al. 1998, as cited by Demchak, Skousen and McDonald, 2003). In fact, researchers have found that within 30 years after closure, water in flooded underground mines in the UK, rose from an acidic to a neutral pH and iron concentrations decreased by over 80% (Wood et al. 1999). Other researchers found that iron and sulfate concentrations declined 11 PADEP, Healing the Land and Water, Pennsylvanias Abandoned Mine Reclamation Program, http://www.dep.state.pa.us/dep/deputate/minres/reclaimpa/healinglandwater.html. 12 But it is important to recognize that not all AML has AMD. AMD is only a subset of the environmental problems associated with AML 13 Ziemkieweicz, Paul F. and F. Allen Meek, Jr. Long Term Behavior of Acid Forming Rock: Results of 11-Year Field Studies. Presented at the International Land Reclamation and Mine Drainage Conference and the Third International Conference on the Abatement of Acidic Drainage, Pittsburgh, PA, April 24-29, 1994.


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by approximately 50 % over 25 years after closure and flooding in two below drainage mines in the Uniontown Syncline of Pennsylvania and concluded that water changed from acidic to alkaline within 30 years after closure and flooding of these mines (Lambert and Dzombak, 2000). A study of the Montour mine, a Pittsburgh coal seam underground mine in Pennsylvania found that a section that was flooded in 1982 changed from being strongly acidic (pH of ~3.0, acidity of 2,200 mg/L) to net alkaline (pH of 6.4, net alkalinity of 200 mg/L) only seven years after flooding, an improvement likely hastened by good quality water from a separate part of the mine that flooded in 1970, (Donovan et al. 2000). Even most underground mines that are above drainage appear to undergo major improvements in water quality with time. These mines experience significant longer term oxygen exposure and more tenacious acidity than surface mines or below drainage underground mines. Yet a 2003 study of 44 such mines in northern West Virginia by Demchak et al. found significant improvements in water quality in 34 of the 44 mines between 1968 and 2000. Reductions in acidity, iron, and sulfate ranged from 50 to 80%. Thus while the AMD problem is very real, it is abating with time. Treatment programs should be designed with this eventuality in mind. Time and reduction in oxygen exposure are two critically important factors for addressing AMD.

1.5.2. Approaches to Remediation The remediation of AMD has been a major concern in Pennsylvania for decades. Hundreds of miles of Pennsylvania streams have been, and are being, improved and even cleaned to near pristine conditions by these efforts. Two traditional approaches have proven extremely effective. The first is surface reclamation, which involves regrading and revegetating a site. The second is passively treating AMD using one of a number of constructed features such as wetlands, open limestone channels and anoxic limestone drains. When designed site specifically and adjusted to improve actual performance, these techniques are virtually 100% successful. 14Both of these approaches, although highly effective, require the expenditure of commonwealth funds. It is estimated that the price of reclamation and remediation of AML and AMD in Pennsylvania approaches several billion dollars. Federal funding from Title IV of SMCRA, the mainstay of reclamation efforts, amounts to approximately $25 million annually. To supplement inadequate federal funding, PADEP has sought ways to encourage private industry to reclaim AML. The lynchpins of these efforts have been the promotion of remining at AML sites where refuse piles can be remined (and the accompanying use of coal ash as an alkaline addition and/or fill) and the permitting of waste coal-burning power plants. Both of these actions have led to todays burgeoning practice of coal ash placement in mines.

14 Milavec, Pamela J., undated, Abandoned Mine Drainage Abatement Projects: Successes, Problems and Lessons Learned, Bureau of Abandoned Mine Reclamation, on PADEP website at http://www.dep.state.pa.us/dep/deputate/minres/bamr/bamr.htm, last revised 1/17/03.


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In the 1990s, Pennsylvania instituted mining regulations that specifically addressed remining areas impacted by AMD. These regulations provide regulatory relief and incentive for mining companies that reclaim problematic AML as a part of remining activities. A large percentage of the coal ash placement in mines occurs at remined sites, because CCW is often used as alkaline addition at these sites to treat AMD or as fill to achieve approximate original contour at the sites. However, the success of remining as a means of remediating AMD is significantly less than the virtual 100 % success rate from passive treatment and the near 98 % success rate from preventing AMD at the permitting stage. An in-depth study of PA remining projects showed a success rate of 87%, or 21 of 24 sites evaluated.15 A broader PADEP study of 110 completed remining operations found net acidity loads were improved or eliminated in 47% of discharges, unchanged in 52 % of discharges and became worse in 1% of discharges. Although the number of discharges with reduced loads of iron, aluminum, manganese and sulfate was always substantially greater than those showing increased loads, 10% of discharges had higher loads of sulfates and 9% of discharges had higher loads of manganese. Furthermore, postmining manganese concentrations in aggregate at these sites actually increased, indicating that virtually all Mn load reductions and most of the reductions in Fe and SO4 were due to flow reductions.16 The degree to which coal ash was used in the remining sites in these studies is not clear. However, the standards for defining success in these cases do not include measurement of groundwater quality nor concentrations of trace elements or other constituents that might migrate from coal ash to surface waters regardless of improvements in loadings for acidity, iron, aluminum, manganese and sulfates. Second, several factors, including the drive to hasten reclamation, have encouraged the proliferation of FBC waste coal-burning plants. The initial driving force for the development of this industry was the passage of the Public Utilities Regulatory Policies Act (PURPA) in 1978. Created in response to the energy crisis in the 1970s, PURPA required electric utility companies to buy the power generated by facilities using non-traditional fuel, such as waste coal. PURPA required electric utilities to purchase this electricity at a rate that matched the traditional power plant cost to produce the electricity. PURPA spawned 16 FBC waste coal plants in Pennsylvania, most built between 1987 and 1995. Today this industry is experiencing a second boom. Reliant Energys Seward Plant, the largest FBC waste coal plant in Pennsylvania, came on line in 2004. At least 2 more large plants, including the Nemacolin plant in Greene County (with slightly larger capacity than the Seward plant), plan to commence operations over the next few years. The Seward plant alone increases the amount of waste coal burned in Pennsylvania and the amount generated from this combustion by approximately 50%.

15 Hawkins, Jay. W. Characterization and Effectiveness of Remining Abandoned Coal Mines in Pennsylvania, 1995. Report of Investigations 9562, U.S. Department of Interior. 16 Smith, Brady and Hawkins. Effectiveness of Pennsylvanias remining program in abating abandoned mine drainage: water quality impacts, 2002, Society for Mining, Metallurgy, and Exploration, Inc


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Pennsylvanias Alternative Energy Portfolio Standard legislation, enacted in 2004, also encourages the burning of waste coal. Act 213 requires a certain percentage of the energy sold in Pennsylvania be derived from alternative energy sources, which included by definition waste coal. PADEP clearly sees waste coal plants/minefilling as a win/win proposition. According to PADEP, Not only are abandoned mine lands reclaimed on the back end of the process through utilization of FBC ash, the reclamation realized at the front end of the process, converting polluting waste coal into an energy resource, could not economically occur if the FBC ash was landfilled.17 FBC plants are the touchstone of the minefilling program; approximately 79% of the coal ash placed in mines is generated by FBC plants.18 The economics of waste disposal also increasingly motivate conventional coal-burning power plants to dispose of their CCW in mines. Seven of the permits examined in this report involved conventional CCW. In Pennsylvania and other coal mining states, coal operators offer attractive haulback provisions that reduce disposal costs for electric utilities. The 21 conventional coal-fired power plants in Pennsylvania produce about 5 million tons of coal ash each year. Over 1.3 million tons of this ash is placed annually in Pennsylvania mines.19

1.5.3. Driving Economic Forces vs. Environmental Concerns The environmental community has raised concerns about the lack of safeguards for mine placement and disposal. The waste coal industry has responded with stiff resistance to any proposed change in their waste handling practices. Waste coal operators claim that any imposition of safeguards for the placement of coal ash in mines would result in closure of their plants.20 This assertion is based on the increased disposal costs that would be incurred if the plants were to dispose of CCW in a residual waste landfill. Proponents of this argument assert that cost of landfilling the 5 million tons of CCW produced each year by the waste coal plants would be in excess of 300 million dollars. By their own estimation, the industry admits that minefilling CCW reduces their disposal costs by 89 to 95% over landfilling.21 Because waste coal plants must burn a substantially higher volume of waste coal, and produce a significantly higher volume of ash than PC plants, the plants are more susceptible to disposal cost increases. 22 Conventional coal plants, because they produce a much smaller volume of ash relative to the power they produce, do not face the same landfilling costs as waste coal plants do. 17 PADEP Coal Ash Report, 2004. 18 Ibid. 19 Ibid. Chapter 1. 20 Joint Legislative Report on Coal Ash. 21 Joint Legislative Committee Report states that This conclusion is drawn with the understanding that the disposal cost per ton of material at a commercial residual waste facility (landfill) is between $45 and $90, including transportation.Taking the midrange of cost to be $67.50 per ton, the cost of landfilling 5 million tons of ash produced each year by the Commonwealths waste coal facilities would be approximately $337.5 million per year. 22 Cogeneration plants are not permitted to increase prices to reflect increased operation costs. Under PURPA, cogeneration and other small power production facilities are entitled to sell electricity to utilities at a negotiated price. Utilities purchase this electricity through long-term (typically 20 years) contracts at a fixed price per kilowatt hour.


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While no one questions the objective of reducing AMD through proper reclamation of active mines, regrading and revegetating abandoned mines and using passive treatment of acid discharges, the dispute centers on whether use of CCW with unstable pH, elevated levels of metals and soluble salts is a prudent long term approach to solving the AMD problem. In particular, PADEP and other proponents of the waste coal industry point out that the electricity produced and the reclamation of AML achieved by burning waste coal would not be economically possible if they have to meet the same disposal standards that generators of CCW must meet when disposing CCW outside of coal mines. However, environmental protection advocates question whether the fundamental objective of protecting and restoring the hydrologic balance in coal mines under SMCRA should be compromised by this economic objective and ask why public funds for reclamation of abandoned mines should not be significantly increased to address the objective of abating AMD on these lands.

CAPTION - The reddish, tan, brown FBC waste coal ash placed in many Pennsylvania Mines stands out against darker gray and black coal refuse. Coal refuse and waste coal are one and the same and called culm if from anthracite coal or gob if from bituminous coal. Here FBC culm ash is being piled on top of culm and mine rock at the AC Fuels Co Mine in northern Schuylkill County, a site not examined in this report. Photo by Steven Dreyer, McAdoo, PA.


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CHAPTER 2: METHODOLOGY FOR EXAMINATION; SUMMARY OF SITES, MONITORING DATA, TRENDS AND EVIDENCE OBSERVED 2.1 Introduction Pennsylvania permits beneficial use of coal ash in active and abandoned coal mines and at coal refuse sites for the following four purposes: coal ash placement, alkaline addition, soil additive or substitution, and as a low permeability material. Most coal ash placement in Pennsylvania coal mines falls under the first two categories; either the coal ash is placed in the mine for reclamation purposes to fill voids and/or achieve ground contours that blend with surrounding topography or it is used as an alkaline addition to improve water quality degraded from acid mine drainage. This report examines water quality impacts from coal ash used for these two beneficial uses in 14 active coal mining permits and one coal refuse disposal permit and also as a low permeability material in one of those mining permits, that for the Wildwood site. The use of coal ash used as a soil additive was assessed preliminarily in the mining permit for the RFI Energy site and the use of coal ash as a low permeability cap was assessed preliminarily at the McCloskey site. However the reviews of these sites as well as those for two other ash minefill sites, the Penn State and Gamelands sites, could not be completed due to limits in project resources. Requirements applying to these beneficial uses are contained in the Pennsylvania Clean Streams Law, Surface Mining Conservation and Reclamation Act, and Coal Refuse Disposal Act and applicable regulations. The primary regulations addressing ash placement in coal mines are found at 25 Pa. Code 287.663, which governs beneficial use of coal ash in active mines, and 25 Pa. Code Chapter 87 Subchapter F and 88 Subchapter G, which govern requirements for the remining of previously mined and abandoned mine lands with seriously impaired water quality. A more detailed summary of the laws and regulations applying to coal ash placement is found in Appendix 2, infra. Regardless of whether coal ash is being placed in an active or abandoned coal mine, the following requirements must be met:

1) The coal ash must meet physical and chemical characteristics outlined in the Certification Guidelines for Beneficial Uses of Coal Ash, 563-2112-224 (BMR PGM Section II, Part 2, Subpart 24). The key requirement is that the ash not leach more than 25 times Pennsylvania Drinking Water Standards for metals and 10 times these Standards for nonmetals and cations in a leaching test (see discussion on pages 9 & 10, Chapter 1);

2) Use of the ash shall be designed to achieve an improvement in water quality or prevent water quality degradation;

3) Ash cannot be placed within eight feet of the regional groundwater table unless PADEP approves a demonstration that groundwater contamination will


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not occur or the placement is approved as part of a mine drainage abatement permit.

Applications for surface coal mining permits in Pennsylvania contain as many as 27 Modules, each of which provides information on a different aspect of the permit. This report focused primarily on Module 25 that identifies and characterizes coal ash proposed for use and outlines plans for placing the ash in the mine and for monitoring its impacts on water quality. The report also relies on information from Module 6 - Environmental Resources Maps, Module 7 - Geology, Module 8 - Hydrology, Module 9 - Operations Map, Module 10 - Operational Information, Module 11 - Coal Refuse Disposal, Module 26 - Remining of Areas with Pre-existing Pollutional Discharges, and Module 27 - Sewage Sludge/Coal Ash Beneficial Use. The following three chapters (Chapters 3 through 5) will include a discussion, on a permit by permit basis, that contains information about each sites geology, geography, hydrology (ground and surface), history of ash placement (with tonnages and ash types), groundwater chemistry trend graphs from ash monitoring data and in some cases, graphs of pollutant loads in surface waters.

2.2. Selection of Permits Out of 110 coal mines permitted by PADEP to accept the placement of coal ash in Pennsylvania coal mines, 12 mine sites in Western Pennsylvania and three in Eastern Pennsylvania were selected for study in this report. These sites met the following criteria developed by the Project Director, Project Researchers and the Advisory Committee for this report:

1. At least 10,000 tons of CCW were dumped or placed in the site (the greater the volume of ash the greater the pollution potential); 2. At least two monitoring points were installed to monitor water quality downgradient and/or downstream from the CCW; and 3. The duration of the total monitoring period extended for at least 5 years.

Many sites meeting these criteria were eliminated because the quality and quantity of the monitoring data were insufficient. Some permits collected considerably more baseline (before ash placement) data than others. The frequency of m

impacts of water quality from placement of coal combustion waste

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