At approximately 0600 hrs on January 9, 2009, a release of Flue Gas Desulfurization (FGD) material (calcium sulfate or gypsum) was discovered by TVA contractor TransAsh. The material is produced when limestone (calcium carbonate) is used to scrub SOx emissions from flue gas. A small amount of fly ash is also sent to the FGD ponds because one of the boilers does not have an electrostatic precipitator. The release occurred at an out of service stand pipe from FGD Pond #2B. The plug in the pipe failed releasing the liquid contents of pond #2B into the stilling pond located below. The material released from the stilling pond when it overflowed into Widows Creek. Widows Creek feeds into the Tennessee River.
EPA received notification on, Friday, January 9th, 2009, at 11:23 am via NRC report (NRC #894379). Duty Officer Nattis deployed R-1 OSC Karen Buerki along with EPA Public Information Officer (PIO) Davina Marraccini and EPA’s START contractor. OSC Buerki arrived on-scene at approximately 1610 hrs and met with TVA’s Environmental Manager R.L. Pope and Alabama’s Department of Environmental Management (ADEM) representative Jim Luken.
TVA provided a helicopter for aerial observation. Cenospheres were observed floating on Widows Creek and out into the Tennessee River. Discoloration from the presence of gypsum was observed in Widows Creek and at the confluence of the Tennessee River, however, it quickly dissipated. The closest drinking water intakes located on the Tennessee River are in Scottsboro and Ft. Payne, AL. They had been notified of the release and chose to draw water from an alternate source until surface water data became available.
Response contractor SWS was mobing equipment onto the site and TVA was mobing in additional personnel and resources to assist in the response. O’Brien Group was called in to assist TVA with implementing the Incident Command System.
A website has been created for further information: http://epaosc.net/TVAWidowsCreekSpill
TVA and their contractor TransAsh are working to secure the pipe and repair the dike wall that began sliding into FGD Pond 2B during the release. TVA’s response contractor SWS placed boom in Widows Creek and the confluence of the Tennessee to aid in collection and removal of cenospheres. TVA has turbidity curtain in route for placement at the release location on the Stilling Pond to prevent additional gypsum from releasing into Widows Creek. TVA is surveying the release location to determine the volume of material that was released to Widows Creek.
EPA, ADEM, and TVA jointly developed a sampling plan for the response. EPA, ADEM, and TVA have been working jointly on press releases, fact sheets and other information shared with the public.
TVA will continue to collect and remove floating solids. TVA will continue repair of the dike and will permanently plug the stand pipe in FGD Pond 2B. Assessment of the extent of gypsum released into Widows Creek and whether or not it should be removed remains to be conducted.
Analytical results from TVA sampling on January 9, 2009, should be available tomorrow. EPA and TVA will continue surface water sampling tomorrow. EPA will begin to transition oversight the ADEM as analytical results become available and as the repairs are completed.
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