The Tennessee Valley Authority has had a second leak at an impoundment at a coal-fired powerplant, this time from a gypsum pond at its Widows Creek Fossil Plant in northeast Alabama. The incident prompted Sen. Barbara Boxer (D-Calif.) to announce on Jan. 13 that she plans to seek federal regulation of coal-ash ponds across the U.S.
Shifting gypsum dislodged the cap covering a 30-in. pipe once used to drain water from the gypsum pond into an adjacent settling pond, says John Moulton, a TVA spokesman. Once the cap came off, water in the gypsum pond flowed into the settling pond, which then overflowed into Widows Creek that flows through the site, Moulton says. Gypsum ponds hold limestone spray from scrubbers that clean sulfur dioxide from coal-fired plant emissions. The 1,456-MW Widows Creek plant has wet-limestone scrubbers on two units. TVA reported to the Alabama Dept. of Environmental Management that the spill was about 10,000 gallons. It has placed booms in the creek to prevent material migration, and state officials are on-site to monitor spill effects. TVA will be required to remediate the area, and it is bolstering gypsum pond internal walls.