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After years of public pressure, litigation, and debate in the aftermath of several high profile coal ash releases, new state and federal regulations have been finalized that will dramatically alter the disposal of coal ash, a by-product of coal combustion during electricity generation. In particular, these new regulations increase pressure to end the use of unlined surface impoundments for coal ash disposal, close inactive surface impoundments at active facilities, ensure that disposal units are structurally stable, and closely evaluate the impacts and environmental risks associated with coal ash disposal. Some of these key new federal- and state-level developments are described below.
Federal
In December 2014, US EPA issued a Final Rule governing the disposal of coal ash in landfills and surface impoundments. This Final Rule came more than 4 years after US EPA’s Proposed Rule, during which time US EPA was sued by environmental groups to make a decision on how to regulate coal ash disposal. Importantly, US EPA decided to regulate coal ash as a solid waste (under RCRA Subtitle D), rather than as a hazardous waste (under RCRA Subtitle C), and retained the Bevill exclusion for coal ash that is used beneficially. Although the waste classification was unchanged, the Final Rule includes other provisions that will bring substantial changes to how coal ash waste is managed.
The scope of the Final Rule, which includes existing and new coal ash landfills and surface impoundments, focuses on four areas: 1) structural stability, 2) groundwater impacts, 3) protective operations, and 4) closure triggers and criteria. The Final Rule establishes the minimum national criteria, leaving considerable discretion for states to establish more stringent requirements (see related discussion, below). In addition, the Final Rule has specific requirements to ensure: structural integrity of the coal ash disposal units; groundwater protection; proper closure; protective daily operations, such as stormwater controls, air criteria, and leachate controls; and adequate and transparent record keeping.
Closure of a disposal unit may be triggered when a unit fails to meet certain “technical criteria” as well as when use stops or the unit is “idled.” The technical criteria include certain location restrictions (e.g., sited in wetlands, in fault areas, in seismic impact zones) and demonstration of structural stability. Existing surface impoundments that are not located at least 5 feet above the water table (or cannot demonstrate that they are not hydraulically connected to groundwater) also must close. While the Final Rule does not require closure of all unlined surface impoundments, closure would be triggered if groundwater is impacted by certain constituents (e.g., arsenic, selenium, mercury), listed in Appendix IV of the Final Rule, above groundwater protection standards (either the maximum contaminant level [MCL] or background concentration); establishing alternate groundwater protection standards is not allowed. The requirement to close inactive (“idle”) impoundments at active facilities is significant, given that many coal fired power plants have converted to natural gas in recent years.
North Carolina
North Carolina Senate Bill 729, known as the Coal Ash Management Act, became effective as North Carolina state law on September 20, 2014. The law requires that the North Carolina Department of Environment and Natural Resources (DENR) classify each coal ash surface impoundment in the state as a high, intermediate, or low risk by December 31, 2015. While the law does not clarify how risk levels at the impoundments will be determined, specific criteria that must be considered are the impoundment’s structural condition, its distance to surface water, the volume of coal ash contained in it, and its proximity to drinking water wells. Impoundment owners will be required to complete receptor well surveys and groundwater assessments during the risk classification stage. After a public comment period, risk classifications proposed by DENR must be approved by a newly created Coal Ash Commission.
Closure plans must be developed for all impoundments. Impoundments classified as “High Risk” must be closed by December 31, 2019; impoundments classified as “Intermediate Risk” must be closed by December 31, 2024; and impoundments classified as “Low Risk” must be closed by December 31, 2029. Coal ash in high or intermediate risk impoundments must be excavated and disposed of in a lined landfill. In-place closure is permitted only for impoundments classified as low risk.
Conclusion
As other states are forced into action by the federal Final Rule and look to follow North Carolina’s lead, this regulatory web will grow more complex, and utilities will need to navigate a maze of federal and state coal ash disposal requirements. This will require careful evaluation of both the environmental impacts and benefits of the different closure alternatives that are being considered. The total cost to implement the federal Final Rule has been estimated at more than $23 billion; how that burden will be shared between shareholders, ratepayers, and insurers remains to be seen.
Additional resources:
Federal Rule
North Carolina Rule
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