The Tennessee Valley Authority is touting a newly operational treatment plan to reduce its land footprint for dealing with coal ash at its six-decade-old, coal-fired Gallatin Fossil power plant in Sumner County.
A new water management system for coal combustion residuals (CCRs) will reduce the footprint from 435 acres to as few as three, according to the TVA. The federal energy entity says the new systems is a step forward from traditional wet ash handling to dry handling and storage landfill.
TVA implemented the system last month, project manager Michael Clemmons noted. The flow management system treats plant process water to remove contaminants such as grease, oil and total suspended solids.
“Until now, Gallatin has utilized a 435-acre ash pond complex to slow treat water compared to the less than three acres of new water treatment tanks, which can treat a maximum flow of 43 million gallons a day,” Clemmons added.
Since 2016, Gallatin (pictured above) has stored dry CCR produced by the Gallatin scrubber in a lined, state-of-the-art 52-acre landfill, but process water and bottom ash was still treated in the ash pond complex. In an effort to move to completely dry storage, the new flow management system will treat the water and temporarily dewater bottom ash (until a permanent dewatering system comes online later this year), replacing the need for an ash pond.
“This flow management system fulfills our commitment at Gallatin to transition from wet to dry CCR handling and storage, which is cleaner, safer and more stable,” Clemmons said.
The system complies with the EPA’s CCR Rule and positions TVA to fulfill the recent agreement between TVA and the Tennessee Department of Environment and Conservation to close the ash pond complex at Gallatin by removal of legacy CCR.
“I’m proud of our team,” Scott Turnbow, vice president of civil projects, said. “Meeting our commitment on CCR is one of the many ways we serve the people of the valley as good stewards of the environment.”
Gallatin’s 976 MW of coal-fired units were built and commissioned in the 1950s. Selective catalytic reduction system to reduce nitrogen oxide emissions and scrubbers to reduce sulfur dioxide emissions were installed on all four Gallatin units in 2016.
A lawsuit was filed in 2015 alleging bad coal ash disposal practices at the site. The TVA settled with the Tennessee Department of Environment and Conservation earlier this year, with the utility promising to remove 12 million cubic yards of CCR.
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The Future of Coal-Fired Generaton is one of the content tracks happening at POWERGEN International later this year. The track’s three sessions will focus on issues such as challenges and sustainability, cycling and advanced technologies for coal-fired plants.
POWERGEN International will be Nov. 19-21 in New Orleans. Registration is open.