© Reuters.

By Georgina McCartney

HOUSTON (Reuters) -The U.S. Coast Guard on Friday was trying to identify the source of an oil spill off the coast of Huntington beach, California, the agency said.

The sheen, estimated at 2.5 miles (4 km) in length and 0.5 miles (800 meters) in width, was discovered after a Coast Guard helicopter flew over the site at sunrise.

The spill is located roughly 2.8 miles (4.5 km) off Huntington Beach, near two oil drilling platforms but it was unclear whether either were the source of the spill, according to the Coast Guard’s statement.

Beta Offshore, a subsidiary of Amplify Energy (NYSE:) Corp, reported a potential spill of produced water from its offshore Platform Elly off Huntington beach on Friday, according to a regulatory filing, causing the company to shut down a pipeline.

It was unclear whether that incident was related to the large oil sheen spotted by the Coast Guard on Friday.

“At this time, we have no indication that this sheen is related to our operations”, Amplify Energy said in a statement.

In September 2022, Amplify Energy Corp agreed to plead no contest to six criminal charges and pay around $5 million in penalties and fines following a significant spill in October 2021.

That spill also occurred off the coast of Huntington Beach, when an underwater pipeline running from the company’s Elly platform to Long Beach leaked around 588 barrels (24,696 gallons) of oil.

The Elly platform has been operating since the 1980s.

“It’s time for state and federal regulators to take tough, urgent action to get this decrepit infrastructure out of the ocean”, said Brady Bradshaw said, a Senior Oceans Campaigner at the Center for Biological Diversity.

Oil production in California has been in a steady decline for nearly four decades, and this year Exxon Mobil (NYSE:) and Chevron (NYSE:) took a combined $5 billion writedown on their assets in the state.

Exxon blamed the states regulatory environment for impeding its business there.