Colbert Ash Pond 4 Seismic Project

Colbert County, Alabama

In September 2021, the Tennessee Valley Authority (TVA) completed an Environmental Assessment (EA) that addresses installing a buttress along a section of the Colbert Fossil Plant Ash Pond 4's eastern dike to provide further protection during and following a large earthquake. Although the likelihood of a seismic event occurring at any given time is very low, TVA takes responsibility seriously to ensure the site's stability. Installing the buttress would require TVA to relocate a 1,700-foot stretch of Cane Creek on TVA property, which currently flows along the length of the ash pond's east dike. Approximately 500 feet of the 6,700-foot dike system would be affected under the proposal. After completing the EA, TVA issued a finding of no significant impact (FONSI) on September 20, 2021. 

In May 2022, TVA issued an amended FONSI addressing the need for additional space for stockpiling soils and materials on TVA's Colbert Fossil Plant reservation to support project activities. TVA amended the FONSI again in December 2022 to address impacts to a wetland area identified in the project area and describe the associated mitigation measures.