The Tennessee Valley Authority will announce in the Dec. 5 Federal Register that it intends to prepare an Environmental Impact Statement (EIS) to address the potential environmental effects associated with management of coal combustion residual (CCR) material produced at the Cumberland Fossil Plant (CUF) located in Stewart County, Tennessee.
The purpose of the proposed EIS is to address long-term management of CCR produced at the plant. The project will help TVA comply with state and federal regulatory requirements related to CCR production and management, including the requirements of U.S. Environmental Protection Agency (EPA’s) CCR Rule and Effluent Limitations Guidelines.
TVA will evaluate the potential environmental impacts of construction and operation of a new bottom ash dewatering facility and options for management and disposal of dry CCR produced at Cumberland. TVA will also evaluate closure of the Bottom Ash and the Main Ash Impoundments. TVA will develop and evaluate various alternatives to these actions, including the No Action Alternative.
Public comments will be taken until Jan. 6, 2017, on both the scope of the review and environmental issues that should be addressed.
Historically, TVA has managed its CCRs in wet impoundments or dry landfills. Currently, Cumberland consumes an average of 5.6 million tons of coal per year, generates approximately 16 billion kilowatt-hours of electricity a year and produces approximately 1.3 million tons of CCR a year, which are managed in an existing fly ash stack, gypsum ash stack, Bottom Ash Impoundment and Main Ash Impoundment. CUF sells approximately 75% of the CCRs produced (725,000 tons gypsum and 275,000 tons of fly ash) annually for beneficial reuse as raw manufacturing material.
In July 2009, the TVA Board of Directors passed a resolution for staff to review TVA practices for storing CCRs at its generating facilities, including CUF, which resulted in a recommendation to convert the wet ash management system at CUF to a dry storage system. In April 2015, the EPA published the final Disposal of CCRs from Electric Utilities rule, also known as the CCR Rule.
In June 2016, TVA issued a Final Programmatic Environmental Impact Statement (PEIS) that analyzed methods for closing CCR impoundments TVA fossil plants and identified specific screening and evaluation factors to help frame its evaluation of closures at its other facilities. A Record of Decision was released in July 2016 that would allow future environmental reviews of qualifying CCR impoundment closures to tier from the PEIS. This EIS is intended to tier from the 2016 PEIS to evaluate the closure alternatives for the existing CCR Bottom Ash Impoundment and Main Ash Impoundment.
The EIS will also evaluate construction and operation of a new bottom ash dewatering facility and management of dry CCR in a new lined CCR landfill meeting Tennessee Department of Environment and Conservation criteria. This project supports TVA’s Board of Directors July 2009 resolution and subsequent recommendation to convert the wet ash management system at CUF to dry storage.
TVA has determined that either the construction of a new on-site landfill or hauling CCR to an existing offsite permitted landfill are the most reasonable alternatives to address the need for dry CCR disposal. A new dewatering facility would dry bottom ash prior to disposal. TVA will consider closure alternatives for the Bottom Ash Impoundment and the Main Ash Impoundment in accordance with and consistent with TVA’s PEIS and EPA’s CCR Rule. No decision has been made about CCR management at CUF beyond the current operations.
TVA anticipates holding a community meeting near the plant after releasing the Draft EIS. TVA expects to release the Draft EIS in summer of 2017.
The two-unit Cumberland plant is the largest generating asset in the TVA coal fleet, boasting a maximum rated gross output of 2,470 MW. Both Cumberland units are equipped with wet limestone scrubbers, which are capable of removing more than 95% of SO2 emissions. In 2003, Unit 1 added a selective catalytic reduction (SCR) system capable of reducing NOx emissions by more than 90%. The Unit 2 SCR was commissioned in 2004 and is also capable of 90% NOx removal.