Tenn. Worker Suffers Cryogenic Burn from Anhydrous Ammonia Leak

June 03--One worker at TVA's Kingston Fossil Plant was treated on the scene for a cryogenic -- or freeze -- burn to an arm after a leak of anhydrous ammonia was detected Tuesday morning.

The chemical is used in the coal-burning plant's emissions control system, and the leak was in an unpressurized line. Anhydrous ammonia in its liquid state is kept at temperatures "well below zero," TVA spokesman Jim Hopson said.

The unidentified worker was wearing protective gear at the time and the injury to his arm was minor, officials said.

Anhydrous ammonia is stored in tanks at an area called the "ammonia farm" near the coal-burning plant and is transported by tankers to the emissions control area where it combines with nitrous oxide, which is used to limit pollution, to form harmless nitrogen and water, Hopson said.

He said TVA is now investigating how much of the chemical leaked, but he and another spokesman, Travis Brickey, said the leak was contained to the immediate area.

Scott Stout, acting director of Roane County Office of Emergency Services, said E-911 dispatchers were contacted by TVA officials at 10:07 a.m. regarding the leak. It was confirmed stopped by 10:50 a.m.

Employees at the site, ordered to report to predetermined areas, were given the all-clear signal at 11:36 a.m.

Kingston Fire Department and Roane County EMS personnel also responded, Stout said.

Brickey said the system to suppress leaks of anhydrous ammonia "performed exactly as designed."

"Once we were on scene, there was no plume visible, the vapors give off a yellow/green color and there were no visible signs," Stout said.

More details as they develop online and in Wednesday's News Sentinel.

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