State, Coast Guard investigating oily sheen in Western Cook Inlet

The view across Cook Inlet from Nikiski.
The view across Cook Inlet from Nikiski. (Riley Board/KDLL)

State officials, the U.S. Coast Guard and one of Alaska’s leading oil and gas producers are investigating the cause and source of a large oily sheen on the west side of Cook Inlet. A pilot flying over the area Monday afternoon reported the sheen to the Alaska Department of Environmental Conservation.

The National Oceanic and Atmospheric Administration says the sheen is near a former oil platform that’s been out of service for decades and is currently owned by Hilcorp Alaska. The platform is in the inlet’s Trading Bay, about 30 miles northwest of Kenai.

Anna Carey is an on-scene coordinator with the Alaska Department of Environmental Conservation. She says the sheen was not visible during flyovers around noon Tuesday or from an oil cleanup ship sent to the site.

“We’re going to continue to look for any signs of sheen and investigate any potential sources here over the next few days,” she said.

Carey says the pilot reported the sheen was “miles long” and also shared aerial pictures. A subsequent flyover by Hilcorp confirmed sheen in the area, but Carey says the department couldn’t confirm the size because the sheen was not visible Tuesday.

The department, the Coast Guard and Hilcorp established a unified command to coordinate the investigation and response. The group says the cleanup ship Endeavor arrived in Trading Bay from Homer around 2:30 a.m. Tuesday and did not detect any oil using its Forward Looking Infrared camera. The ship has oil recovery equipment and can temporarily store material.

Although the nature and source of the sheen is still unknown, Carey says the state is responding as if it’s an oil spill.

“Sheen can be caused by proteins or other natural causes,” she said. “Generally there’s a rainbow-ish component to it. We figure it’s from a petroleum product, but at this time we’re still investigating.”

Hilcorp says the Spark Platform became inactive in 1992 and that wells associated with the platform were plugged and abandoned in 2009.

Carey says any sheen should be reported to the state, and that they don’t expect leaks or sheen from platforms that were properly decommissioned.

A situation report published by the state says there have been no reported impacts to wildlife. The department says all five salmon species are found in the area.

The department says it plans to continue monitoring the area and investigate the source and cause of the sheen. Carey says whoever is responsible for the spill is also responsible for cleaning it up, but that the state oversees those operations.

KDLL - Kenai

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