The Tennessee Valley Authority said June 13 that it is proposing a long-term storage solution for its coal ash and other coal combustion residuals that would safely keep these products on TVA property permanently.
The recommendation for closure-in-place is part of a new Final Environmental Impact Statement addressing options for CCR impoundments at its coal-fired power plants. The EIS is divided into two parts:
- Part 1 is a programmatic analysis that should generally apply to any CCR impoundment in the TVA system.
- Part 2 is an analysis of 10 site-specific ash impoundment closures, which integrates the findings and conclusions of Part 1.
The proposed and preferred closure method for the specific sites is the closure-in-place alternative, but the document also considers the impacts of closure-by-removal.
CCRs are byproducts produced from the combustion of coal or the control of combustion emissions and include fly ash, bottom ash, and other materials. The Final EIS supports TVA’s goal to eliminate all wet CCR storage at its coal plants and to help TVA comply with the U.S. Environmental Protection Agency’s CCR Rule.
TVA conducted extensive public outreach in preparing this document, including a public comment period that lasted more than 60 days and 10 open house meetings in communities near its fossil plants to allow the public to discuss the draft EIS and provide comments in person and online. TVA said it has addressed all substantive comments received during the comment period in the Final EIS. Although not required, TVA will accept comments on the Final EIS through July 9.
In the CCR Rule, EPA encouraged utilities to close and cap impoundments quickly because this would significantly reduce groundwater contamination and structural stability risks. TVA identified 10 CCR facilities at six of its plants that it could close quickly. They are at the Allen, Bull Run, Kingston and John Sevier plants in Tennessee and at the Widows Creek and Colbert plants in Alabama.
Recognizing the potential pathways for exposure and risk related to existing CCR impoundments, TVA developed a series of factors important in the screening and evaluation of closure alternatives. TVA used these factors to determine which closure alternatives should be considered in greater detail in its site-specific analyses. Key factors that TVA considered included: volume of CCR materials, schedule/duration of closure activities, stability, risk to people’s health and safety relating to closure activities, mode and duration of transport activities, potential human health risk associated with CCR constituents in the existing impoundments, effects to wetlands, risk to adjacent environmental resources, and cost.
Based on these factors, Closure-in-Place was analyzed in detail at all sites. Closure-by-Removal also was analyzed in detail at Allen Fossil Plant and John Sevier Fossil Plant. Based on the programmatic and site-specific analyses, TVA has identified Closure-in-Place as its preferred alternative for all 10 facilities. This alternative would achieve the purpose and need for TVA’s proposed actions and compared to Closure-by-Removal with less environmental impact, shorter schedules, and less cost.