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Miscellaneous Frequent Questions about Implementing the Final Rule Regulating the Disposal of Coal Combustion Residuals (CCR)

EPA developed a list of responses to the many questions the Agency received about implementing the 2015 final CCR disposal rule. Questions that fall under the category of miscellaneous and their responses are below:

  • What information will EPA gather over the next several years to resolve these technical uncertainties?

    Over the next several years, electric utilities will be moving forward in the implementation of this rule as well as the Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category (the ELG rule) and the Carbon Pollution Emission Guidelines for Existing Stationary Sources; Electric Utility Generating Units Clean Power Plant rules.

    Until these regulatory requirements are implemented, it is premature to define a path forward for resolving the technical uncertainties identified in the final rule. A reasonable course, however, would be to follow the groundwater monitoring data and other information being posted to companies' websites to see what facilities, CCR landfills, and CCR surface impoundments continue operating, whether liners are leaking, and what concentration of contaminants we are observing. Any information that the EPA gathers in the future will be announced to the public and offered for public comment.

  • The final rule identified the possibility that concentrations of hazardous contaminants in coal ash may rise in the near future. Why might that happen? What actions might be necessary if that happens?

    In the final rule, EPA specifically noted that there were uncertainties regarding the evolving characterization and composition of CCR due to electric utility upgrades and retrofits of multi-pollutant control technologies and raised concern that these advances in human health and environmental protection could present new or otherwise unforeseen changes in CCR. Therefore, if the Agency determines a t some future time that significant changes have occurred in the characterization or composition of CCR as a result of these increased air pollution control efforts, EPA will then make a determination on how state programs are addressing those risks and whether additional risk analyses are warranted. This determination may be strongly influenced by the monitoring of facility groundwater data to determine if the controls the Agency has put in place as a result of this rule are providing the necessary environmental protections. Any action that the Agency may consider in the future will be announced to the public and offered for public comment.

Want to look at all of the 2015 final rule implementation questions at once? Check out the complete list in PDF format.