A 30,000-gallon diesel spill near Sitka's port on Saturday morning sent 2,500 gallons through Sitka's storm drain system to Sitka Sound when a valve on a secondary containment area failed, state and Coast Guard officials said.
The Coast Guard responded to Sitka's Jarvis Street Diesel Plant on reports of a spill of diesel into a large concrete basin designed to hold spilled fuel. A call to Sitka's fire department at about 11 a.m. indicated a sheen on Sitka Sound waters near the plant.
The plant supplies power for Sitka's borough-owned electric utility. The Alaska Department of Environmental Conservation said it was still working Monday morning to determine the cause of the spill into the diesel containment area, although initial reports indicated a storage tank might have ruptured.
Coast Guard, DEC, local tribal organizations, the National Park Service and Sitka city officials were continuing cleanup work Monday.
The state said some of the diesel made its way into Sitka Sound, near the mouth of the Indian River.
DEC spokesperson Candice Bressler said booms and absorbent materials have been deployed inside storm drains to soak up any remaining diesel.
"At this point we haven't had any recoverable or free product there, so that indicates that the absorbent materials used inside the storm drain are working."
So far, the Coast Guard said, about 23,000 gallons of diesel have been recovered from the secondary containment area surrounding the tank that is believed to have leaked -- leaving about 7,000 gallons unaccounted for.
Unlike raw petroleum, commonly called crude oil, diesel is a light product and evaporates quickly. DEC officials said they hoped that would aid in their cleanup efforts.