Operators of the Southern California oil pipeline that leaked 144,000 gallons of heavy crude into the Pacific Ocean didn't shut it down for more than three hours after an alarm alerted them to the possible breach, federal regulators said.
A corrective action order, which federal pipeline and hazardous materials regulators issued to a subsidiary of Amplify Energy Corp. on Monday, includes a timeline that says the subsidiary, Beta Offshore, was alerted to a "low-pressure alarm" that indicated "a possible failure" at 2:30 a.m. Saturday.
More than three hours later, the pipeline was shut down, and after three more hours, Beta Offshore reported the leak to the federal National Response Center, according to the timeline.
Amplify did not immediately respond to a request for comment Tuesday night.
The spill off Orange County has resulted in oiled birds and a prohibition on fishing from the coastline to 7 miles offshore, from Huntington Beach to the San Diego County line.
Gov. Gavin Newsom has declared a state of emergency for the county.
The corrective action order said the pipeline appears to have failed 5 miles offshore at a depth of nearly 100 feet.
Pipeline integrity and compliance consultant Andrew Kendrick of Kendrick Consulting LLC said leak detection systems are usually effective when it comes to major breaches.
"They cannot detect small leaks because of the large volumes being transported, so you can have a small leak that goes on until you find it in a sheen somewhere because the leak detection systems just can't see it — it's a physics problem," he said.
"However, with a catastrophic failure, the leak detection systems are very effective and give very prompt detection," Kendrick said.
Even some larger leaks aren't always immediately detected, industry experts say. One reason is that at some depths, seawater pressure can affect readings.
A Coast Guard statement Tuesday isn't entirely consistent with the timeline compiled by federal pipeline and hazardous materials regulators under the U.S. Transportation Department.
The Coast Guard said the National Response Center fielded a report of an oil sheen on the water off Orange County on Friday night. Authorities weren't able to investigate until first light Saturday, the Coast Guard said.
The agency said such reports were "common" and noted that they don't necessarily indicate pipeline leaks.
The federal corrective action order coincides with investigators' suspicion about the origins of the breach — that it might have been caused by "an anchor that hooked the pipeline."
"A 4,000-foot section of the 17.7 mile-long pipeline was displaced with a maximum lateral movement of approximately 105 feet and had a 13-inch split, running parallel to the pipe," the Coast Guard said in its statement.
The aquatic region of San Pedro Bay is the site of a shipping traffic jam where large vessels are lined up waiting to offload goods at the ports of Los Angeles and Long Beach.
"Anchor strikes are not uncommon, and with the current vessel backlog in San Pedro Bay, everything seems to have lined up to be a vessel anchor strike," Kendrick said.
In 1992, an underwater survey of the same pipeline detected a dent from an anchor that didn't cause a leak. A structural clamp was used to make a repair, according to documents from the Pipeline and Hazardous Materials Safety Administration, the federal regulatory body that oversees oil pipelines.
The pipeline was under different ownership at the time.