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8 Synthesis of Issues for Planning and Regulation of Coal Combustion Residue Mine Placement A s reviewed in previous chapters, CCRs contain an array of metals and elements in such quantities that they are of toxicological concern. Case studies of landfills and surface-water impoundments have shown that if CCRs are not managed adequately, they can adversely impact water supplies and ecosystems. The U.S. Environmental Protection Agency (EPA) has not specifi- cally attributed significant environmental problems to CCR use in minefills, but better data are needed to fully characterize this issue. In abandoned mine lands (AMLs) and coal-refuse remining applications, two specific reclamation settings, the use of CCRs has helped to resolve serious, acute land-use and water quality problems. However, when not managed properly, CCRs may produce undesir- able consequences, such as the release of metals and metalloids into the environ- ment. As a result, although the placement of CCRs in mines is localized in coal mining districts, it has raised public and regulatory concerns. The intent of this chapter is to synthesize some key observations of this report. It discusses the steps involved in planning for CCR use as minefill. This chapter further describes some of the cross-cutting policy and implementation issues and summarizes the alternatives with regard to regulatory oversight. PLANNING FOR CCR MANAGEMENT The placement of CCRs in coal mines is a multidimensional issue that in- volves consideration of potential human health and environmental impacts, as well as a comparison to the economic, health, and environmental impacts from other uses or disposal options. This section outlines the steps involved in CCR 177
178 MANAGING COAL COMBUSTION RESIDUES IN MINES management planning, highlighting for both site managers and regulators the specific considerations necessary when placing CCRs at a mine site. Several of the improved management practices presented in Chapters 6 and 7 that would reduce the risks associated with the use of this material are summarized here. Step One: Considering CCR Disposal and Use Options CCRs are often characterized as coal combustion wastes because the genera- tors of CCRs are in the business of producing electricity or some other product that requires coal combustion. Some of these residues, however, are valuable for other uses. Coal combustion residue use in the production of cement and wall- board, for example, results in a needed product for society and reduces the im- pacts of other resource extraction activities (e.g., gypsum or limestone mining). The value of these residues has produced its own industry association--the American Coal Ash Association--founded to promote the use of these CCR products. As discussed in Chapter 2, many factors enter into the decision-making process when considering the options for CCR utilization or disposal. Such fac- tors include the local applications for utilizing CCRs, the economic value of CCRs for alternate uses, the transportation distance to industries able to use CCRs, the location and costs of CCR disposal options, the local regulatory envi- ronment, and the potential effects on human health and the environment. Valuable residues that become part of the waste stream may represent a missed opportunity for waste reduction and environmentally sound management. Thus, the committee recommends that secondary uses of CCRs that pose minimal risks to human health and the environment be strongly encouraged. Public-private cooperative efforts, such as the Coal Combustion Products Part- nership, are examples of programs that can foster research and product develop- ment to further the productive uses of CCRs. Government agencies should exam- ine ways in which they can promote CCR use or remove impediments to its use (see Sidebar 5.2 for a discussion of proposed actions in the Energy Policy Act of 2005). Careful planning for residues should also be undertaken by utilities and other CCR generators. However, many CCRs are not suitable for such uses and must be disposed in landfills, impoundments, and mines. The committee concluded that putting CCRs in coal mines as part of the reclamation process is a viable management option as long as (1) CCR placement is properly planned and is carried out in a manner that avoids significant adverse environmental and health impacts and (2) the regula- tory process for issuing permits includes clear provisions for public involvement. The main advantages of CCR mine placement are (1) it can assist in meeting reclamation goals (such as remediation of abandoned mine lands), and (2) it avoids the need, relative to landfills and impoundments, to disrupt undisturbed
SYNTHESIS OF ISSUES FOR PLANNING AND REGULATION 179 sites. As noted throughout this report, the volume of CCRs to be used and the relative risk that emerges from characterization of the site and the CCR material should help dictate the level of additional effort that will be required to manage and monitor the mine site. Step Two: Characterizing a Mine Site Disposal Option CCR Characterization Routine analysis of the CCRs intended for mine placement is necessary to identify potentially toxic materials and ultimately to ensure that the CCRs are adequately emplaced and managed. CCR characterization alerts managers to potential environmental problems associated with CCR disposal in the mine en- vironment and provides information on material properties that can be used to manage its containment. The CCR characterization should include identification of the volume of material, its physical and chemical characteristics, its trace element leaching potential, and its cementitious properties. As noted in Chapter 6, improved methods for characterization are needed. Site Characterization In conjunction with the characterization of the CCRs, managers must also identify the best disposal site(s) within the mine. As described in detail in Chapter 6, site characterization should include a full description of the hydrogeological setting, including aquifer locations and groundwater flow patterns, surface-water drainage and flow, and soils and overburden characterization. The site character- ization should also consider local factors, such as surrounding land use, proxim- ity to sensitive surface waters, and designated future land use. These factors will further the assessment of the potential for human exposure to drinking water impacts that might occur related to CCR placement. Much of the information needed to characterize the site should or could be available as a result of compli- ance with the SMCRA's permitting requirements, including information devel- oped in conjunction with the probable hydrologic consequences (PHC) determi- nation and the cumulative hydrologic impact assessment. As noted in Chapter 6, however, further data may be needed to address issues that are particularly asso- ciated with CCR placement. For example, while the PHC determination will likely include baseline monitoring data for the mine site as a whole, additional data may be needed to adequately characterize groundwater flow rates and direc- tions within a mine site that is scheduled to receive CCRs. Depending on the acid-producing potential of the mine site, acid-base accounting may be needed. Thus, permit requirements may need to call for additional characterization data related to the specific sites where CCRs will be placed.
180 MANAGING COAL COMBUSTION RESIDUES IN MINES Integration of Characterization Data The site and material characterization data must then be integrated to enable appropriate considerations in the design of the management, engineering, and monitoring plans at the site, including how the CCRs will be emplaced to mini- mize potential movement of contaminants (see Chapter 7). This should consider the mass of material to be placed, as well as options for placement locations within the mine site. Step Three: Developing a Long-Term Management Plan for the CCRs Mine placement of CCRs that is protective of human and ecological health requires the development of a long-term management plan, including careful attention to engineering design and monitoring. The following sections discuss CCR management issues to be considered during active mining and reclamation activities as well as those relevant to the post-reclamation period. Management During Active Coal Mining and Reclamation Operations As noted in Chapter 7, the engineering design, including the method of placement as well as the location of placement of CCRs in the mine, should be informed by the estimated risk from the CCR material and the site characteristics. Monitoring plans should include sampling sites that can specifically address potential contamination from the CCR placement. In addition, many issues should be incorporated into plans for the placement of CCRs in mines. Some examples of issues that should be considered are the following: · Is simple backfilling, mixed with mine spoil, adequate, or are more con- trolled placement approaches needed? · Should the cementitious properties of the ash be enhanced to minimize interaction with groundwater? · Should the CCR be put down in small lifts and compacted to minimize its hydraulic conductivity and minimize contaminant transport? · Can CCRs be emplaced in a manner that neutralizes acidity at the mine over the long term and reduces overall contaminant transport? · Will placement of CCRs above the water table be sufficient to minimize contaminant transport, considering local recharge rates? · How many additional monitoring wells, specific to the CCR placement, are needed? · What additional parameters, related to CCRs, should be required for moni- toring, and at what frequency? · Are additional bonding or other financial assurances necessary to cover potential off-site contamination from CCRs?
SYNTHESIS OF ISSUES FOR PLANNING AND REGULATION 181 Disposal of CCRs in coal mines should be subject to reasonable site- specific performance standards that are tailored to address potential envi- ronmental problems associated with CCR disposal. These requirements may be in addition to any permitting requirements associated with mine-site and CCR characterization. For example, the maximum containment levels established un- der the Safe Drinking Water Act might be used as a benchmark for determining unacceptable contamination levels for groundwater at some appropriate, desig- nated monitoring site. In some mined areas, however, the natural groundwater is of poor quality, and some relative non-degradation approach may be needed. In areas where CCR leachate may interact with surface water (directly or through groundwater interactions) more stringent requirements may be necessary to pro- tect aquatic life (see Chapter 4, Sidebar 4.5). Where violations of permit require- ments or performance standards occur, authority for appropriate penalties or corrective actions must be available to mitigate the damage and prevent future violations. Post-Mining and Reclamation Land Management The committee reviewed various post-mining, post-closure concerns related to long-term CCR management at mine sites. Of these, the committee could not resolve their concerns nor reach consensus on the duration of long-term ground- water monitoring, the recommended length of liability (in relation to current SMCRA reclamation bond requirements), and future land-use restrictions. The committee believes that groundwater monitoring, linked to performance standards, is essential to confirm the performance of the management plan and to protect both human and ecological health (see Chapter 7). The overall extent of monitoring, including its duration, should be customized to address the level of estimated risk and the uncertainties associated with the site. As discussed in Chapter 3, the committee is concerned that the geochemical conditions in some settings may evolve and create long-term groundwater contamination that might have off-site impacts, particularly when large volumes of CCR are used as fill material. If monitoring sites are not critically placed to yield early data on con- taminant transport, the movement of contaminants could go undetected for long periods of time. This in turn raises concerns about the length of the liability period and the adequacy of the remaining reclamation bond to deal with adverse groundwater impacts that may occur after bond release. As described in Chapter 7, SMCRA requires mine operators to maintain a portion of their bond for at least five years and, in arid areas, for at least ten years after the completion of all reclamation activities, including revegetation. The portion of the bond that remains during this post-mining period is intended pri- marily to cover the costs associated with a failure of revegetation. Once a bond has been fully released, the mine operator's responsibility for compliance with SMCRA effectively ends. At some sites, particularly those with inadequate moni-
182 MANAGING COAL COMBUSTION RESIDUES IN MINES toring, there is potential for longer-term groundwater impacts from CCRs to go undetected under the normal reclamation bonding framework. Some committee members expressed concern that if significant contamination were detected after bond release, there would be no ready remedy available to the public. Some committee members believed that longer-term groundwater monitoring should be required in all cases and that release of the bond should be tied to such monitor- ing. Other committee members felt that there was insufficient evidence to require this in all cases. Some committee members also believed that the longer-term reclamation bond liability would be a significant deterrent to the use of CCRs in mine reclamation--a practice that the committee agrees can provide environmen- tal benefits when managed properly. Part of the complexity is that the liability under SMCRA bonding requirements falls only on the mine operator--not on the generator of the CCRs--and there is little incentive for the mine operator to accept a longer term of liability. Because the committee was unable to reach consensus on the duration of long-term monitoring and liability, it focused instead on ways that monitoring systems can be designed to enable early detection of potential problems (i.e., during the established bonding period), so that performance can be confirmed and mitigation initiated, if needed (see Chapter 7). As noted, a possible parallel exists between undesirable impacts of CCRs and the formation of AMD at sur- face mines requiring long-term treatment. If AMD is detected before final bond release, the OSM has the authority to require the bond amount to be adjusted accordingly and held indefinitely until it is replaced by some other enforceable contract or mechanism to ensure continued treatment (OSM, 2002). There are other long-term legal remedies after bond release, if damages occur, but they are more difficult to impose (see Chapter 7). Therefore, the regulatory authority should take care to review the management and monitoring plans, including the term of monitoring, considering the risk of CCR placement at the site, the bond release terms, and the potential corrective actions that may be warranted should significant contamination occur. The permit application process requires that the mine operator consider and plan for the use of the land at the mine site after reclamation and closure (see Chapter 7). The committee believes that mines reclaimed with large volumes of CCRs should be able to achieve economically productive post-mine land uses as long as CCR management at the mine site is based on careful consideration of characterization data and includes appropriate design safeguards to minimize the movement of CCR-derived contaminants into the environment. However, the committee believes that deeds, or appropriate recordable instruments, should record and fully disclose that CCRs were used in the reclamation of the mine site. The records should provide CCR placement locations as specifically as possible. Such records can help guard against future inappropriate land uses (e.g., irrigated crop production at a site that was engineered to minimize water and contaminant movement under normal [natural] rainfall conditions). The committee discussed
SYNTHESIS OF ISSUES FOR PLANNING AND REGULATION 183 whether deed restrictions were needed, such as those used on brownfield redevel- opment sites. The committee, however, could not agree if additional levels of regulatory control should be specified with respect to post-mining land use, be- yond full disclosure of the site history. Abandoned Mine Lands and Remining Sites. A special consideration is the use of CCRs in reclaiming AML and remining sites and in mining coal refuse piles. As noted in Chapter 5, any regulatory standards for CCR use adopted under SMCRA for active coal mining would most likely apply to remining activities but would not apply directly to CCR use in the reclamation of abandoned mine lands. To ensure adequate protection of public health and the environment, the commit- tee recommends that placement of CCRs in abandoned and remining sites be subject to the same CCR characterization, site characterization, and man- agement planning standards recommended for active coal mines. However, when developing performance standards, adequate consideration should be given to the significant differences between active mines, abandoned mines, and the remining of previously abandoned mine sites. At such abandoned sites the CCR placement process begins with a degraded site and the same management options available in an active mine site may not always be feasible. The plans should consider the benefits of CCR use for reclamation at these degraded sites but should also factor in the potential adverse impacts of CCRs, accommodating these concerns in the overall plan. OVERARCHING ISSUES AND CONCERNS The committee was tasked to address several overarching issues, including the current provisions for public involvement and the protection of natural re- sources from CCR mine placement offered by the RCRA and SMCRA. Detailed background information on the current regulatory framework can be found in Chapter 5, but the following section builds upon concerns addressed throughout the report and outlines the committee's recommendations and conclusions on these overarching topics. Public Participation The committee heard from many individuals who were concerned about the potential for adverse environmental and public health impacts from improper CCR disposal. As noted in Chapter 1, many of the issues of concern are beyond the charge of this study. In recognition of the public concern, however, govern- ment agencies responsible for regulating CCRs should ensure that the public receives adequate advance notice of any proposals to dispose of CCRs in mine sites. The public should also be encouraged to participate actively in agency decisions for CCR disposal. Agencies could use stakeholder engagement pro-
184 MANAGING COAL COMBUSTION RESIDUES IN MINES grams to engage members of the public, identify their concerns, and obtain their input on needed programmatic improvements. The committee recommends that any proposal to dispose of substantial quantities of CCRs in coal mines should be treated as a "significant alteration of the reclamation plan" under Section 511(a)(2) of SMCRA (30 U.S.C. §1261(a)(2)). This will ensure that the public is afforded adequate notice and an opportunity to be heard on the CCR placement proposal. The regulation of CCR placement under SMCRA would also provide additional opportunities for public input, such as formal citizen's complaints with the appropriate regulatory agency (e.g., SMCRA, §517(h)(1); 30 U.S.C. §1267(h)), and the opportunity to accompany an inspector during the inspection related to a formal complaint (30 U.S.C. § 1271(a)(1)). Under SMCRA, the agency must provide a written response about the disposition of such a com- plaint. In addition, government agencies should make usable monitoring data from CCR disposal sites available to the public in a timely manner. Alternatives for Regulatory Authority As noted in Chapter 5, there are existing regulatory programs that can pro- vide for the management of CCRs placed in mines. The scope of SMCRA is sufficiently broad to allow comprehensive regulation of CCRs at mine sites. However, neither SMCRA nor its implementing regulations currently address the use or placement of CCRs in an explicit manner. As a consequence, states vary in their approach and the rigor with which they address CCR use in mines. Some states have developed their own detailed regulatory oversight programs for CCR placement in mines, while other state agency representatives expressed concern that they do not have the authority to impose permitting requirements or perfor- mance standards specific to CCRs. As discussed in Chapter 5, EPA reported in 2000 that it will promulgate regulations covering CCR disposal in landfills and surface impoundments under RCRA Subtitle D (65 FR 32214). EPA has not yet decided, however, whether regulation of CCR disposal in minefills should occur under SMCRA, RCRA Subtitle D, or some combination of the two. Currently there are variations and gaps in the regulation of CCRs used for reclamation. These gaps create opportunities for unnecessary risks to water supplies and the environment. Therefore, the committee recommends that enforceable federal standards be established for the disposal of CCRs in minefills. Enforceable federal standards will ensure that states have adequate, explicit authority and that they implement adequate minimum safeguards. This would be accommodated by explicitly addressing CCR minefilling in the fed- eral regulations that are delegated to or adopted by the states. As with current federal regulations and standards, the committee does not envision, nor recom- mend detailed national design standards. Rather, enforceable federal standards would require that state programs develop and implement needed management and performance standards specific to CCRs and minefilling (see Chapters 6
SYNTHESIS OF ISSUES FOR PLANNING AND REGULATION 185 and 7). As with current federal regulations, these rules should provide suffi- cient flexibility to allow states to adapt permit requirements to site-specific con- ditions, while providing needed focus on the protection of ecological and human health. There are three primary regulatory mechanisms that could be used to develop enforceable standards that would reduce the risks imposed by CCR minefilling: 1. Changes to SMCRA regulations to address CCRs specifically; 2. Joint OSM-EPA rules pursuant to the authority of SMCRA and RCRA; or 3. RCRA-D rules that are enforceable through an SMCRA permit. Under SMCRA, the OSM and related state agencies that implement SMCRA currently have the regulatory framework in place to deal with CCRs used in mine reclamation and have considerable expertise in review, permitting, and manage- ment of mine lands. On the other hand, under RCRA, the EPA and its counterpart agencies at the state and local level have developed significant technical and regu- latory expertise in monitoring and oversight of waste disposal operations (e.g., landfills) that involve groundwater and potentially toxic substances. The committee believes that OSM and its SMCRA state partners should take the lead in developing new national standards for CCR use in mines because the framework is in place to deal with mine-related issues. Nevertheless, most individuals and public-interest groups that appeared before the committee expressed a lack of confidence that SMCRA agencies can deal with these issues. This lack of public trust should be remedied. Joint rules from OSM and EPA might help in this regard, although such efforts often lead to problems in defining clear lines of authority. Regardless of the regulatory mechanism selected, coordination between OSM and EPA efforts is needed and would foster regulatory consistency with EPA's intended rule propos- als for CCR disposal in landfills and impoundments. In all cases, guidance documents will also be necessary to help states imple- ment their responsibility for managing CCRs. However, guidance alone is not adequate to achieve the needed improvements in state programs for CCR minefills. Guidance is not enforceable, nor does it afford adequate opportunities for citizen participation otherwise guaranteed under SMCRA. As noted in Chapter 5, some states have statutes that prohibit state agencies from adopting standards that are more stringent than federal standards, thereby restricting states from strengthening their regulatory programs based on guidance documents alone. Only through en- forceable federal standards can acceptable minimum levels of environmental pro- tection from CCR placement in coal mines be guaranteed nationally. SUMMARY Placement of CCRs in mines as part of coal mine reclamation may be an appropriate option for the disposal of this material. However, an integrated pro-
186 MANAGING COAL COMBUSTION RESIDUES IN MINES cess of CCR characterization, site characterization, management and engineering design of placement activities, and design and implementation of monitoring is required to reduce the risk of contamination moving from the mine site to the ambient environment. The committee also recommends that placement of CCRs in abandoned and remining sites be subject to the same CCR characterization, site characterization, and management planning standards recommended for active coal mines. The scope of SMCRA is broad enough to encompass the use of CCRs at a mine site during reclamation activities, but neither SMCRA nor its implementing regulations explicitly address the use or placement of CCRs. As a result, regula- tory gaps exist that create opportunities for unnecessary risks to water supplies and the environment. To address this issue, the committee recommends that enforceable federal standards be established for the disposal of CCRs in minefills to ensure that states have specific authority and implement adequate safeguards. The chapter lists three regulatory alternatives for establishing such standards for CCR mine placement. No matter what alternative is used, enforceable federal standards are necessary to guarantee acceptable minimum levels of environmen- tal protection wherever CCRs are disposed.