The Tennessee Valley Authority said Nov. 16 that it plans to fully decommission and remove power generation facilities at the retired Colbert Fossil Plant near Tuscumbia, Ala., making it available for commercial or industrial use.
TVA examined four possible alternatives for the site – maintaining the existing structures and equipment; a no action alternative; and two deconstruction options, one of which would retain the powerhouse for possible future use – as part of an Environmental Assessment. A Finding of No Significant Impact was issued on Nov. 9 in support of TVA’s preferred alternative, which is to return the site to a “brownfield” state through demolition to three feet below final grade. The five chimney stacks would be removed using explosives, manual deconstruction, or a combination of both.
The final method of demolition will be determined during development of the deconstruction plan. The EA found only minor impacts associated with the two deconstruction options. Demolition work is scheduled to begin in late 2017.
At the Colbert Fossil Plant (COF) there are five coal-fired units and eight combustion turbine units. Coal-burning Units 1 through 4 were constructed in the 1950s with all four units in commercial operation by November 1955. Units 1 through 4 had a generating capacity of 200 MW each. Unit 5 was authorized for construction in the spring of 1959 and entered commercial operation in the summer of 1965. Unit 5 had a generating capacity of 500 MW. The coal units ceased all power generation in March 2016. All combustion turbine units at COF will continue to operate and are not considered in the final Environmental Assessment.
Decommissioning activities at COF have already begun on Unit 5 under an agreement that TVA entered into with the U.S. Environmental Protection Agency in April 2011. Decommissioning is the performance of activities required to ready a facility for deactivation and demolition. Work to be performed includes removal of equipment, components, and parts that can be used at other TVA sites, draining of oil/fluids from equipment, removal of ash from boilers, removal of polychlorinated biphenyl (PCB) transformers, removal of furniture/furnishings, removal of information technology assets, removal of plant records, etc. TVA’s agreement with EPA is a Federal Facilities Compliance Agreement (FFCA) that resolved a dispute over how the Clean Air Act’s New Source Review program applied to maintenance and repair activities at TVA’s coal-fired power plants.
TVA also entered into a judicial consent decree with the states of Alabama, Kentucky, Tennessee and North Carolina, and three environmental advocacy groups. The consent decree is substantively similar to the FFCA. These agreements (collectively called the “EPA Agreements”) require TVA to reduce emissions across its coal-fired generating system and take other actions at its coal plants, including retiring some of its units (hence TVA’s retirement of Colbert Units 1-5). The EPA Agreements do not affect the operation of the combustion turbine units.