Less than a year after installing new coal scrubbers at its Kingston Fossil Plant, TVA is spending $53 million to change the way it handles the gypsum ash produced in the process.
TVA directors on Friday agreed to build a new gypsum dewatering facility in Kingston, where ash leaks over the past two years have polluted the nearby Emory and Clinch Rivers.
After a December 2008 ash spill dumped more than 5 million cubic yards of coal ash into the river and surrounding properties, TVA agreed to phase out such ash ponds at all six of the coal plants that use such methods.
TVA Chief Operating Officer Bill McCollum said ending wet storage of ash also will require the utility to replace a gypsum ash pond built to store wastes from the wet scrubbers installed at Kingston to cut sulfur dioxide emissions.
"This is one project of several in our overall program that allows us to close all of these wet storage impoundments at our coal plants," McCollum said.
TVA began dumping the gypsum in a new pond at Kingston last summer. But in December, a breach in the pond wall leaked water from the pond into the nearby Clinch River.
Another gypsum pond at TVA's Widows Creek Fossil Plant in Northeast Alabama began leaking into the Tennessee River in January 2008.
In response to the Kingston gypsum pond leak, the Tennessee Department of Environment and Conservation ordered TVA to suspend use of the pond and remove the water from the impoundment.
"The order also requires a detailed corrective action plan, which must include a plan for inspecting and determining the structural integrity of the landfill, a plan for subsurface investigation, for managing gypsum during the shutdown and for stabilization and repair," said Tisha Calabrese-Benton, TDEC's communications director.
The dewatering facility approved by TVA directors Friday was planned even before the December gypsum pond leak, McCollum said.
"This new project will meet future water discharge regulations by installing a dewatering facility that takes the water out of the gypsum that is in the scrubber and processes it so we can meet the new requirements," McCollum said.
The Kingston coal ash spill in late 2008 was the worst such spill in U.S. history and has led TVA to revamp the way it manages and handles coal wastes. The utility is about 20 percent complete in its overall $1.2 billion program to convert all its coal ash disposal methods to dry storage or recycling, McCollum said.
TVA President Tom Kilgore said the utility has completed its inspection and upgrades of existing impoundment walls.
"We didn't find any major problems, but we did find some (pond structures) that we wanted to improve," he said.
TVA Director Mike Duncan, who served as chairman of TVA when the utility responded to the Kingston ash spill, said he is "pleased with the staff progress" so far.
"We're progressing and doing what we set out to do," he said.