HUNTINGTON BEACH (CNS) — A pipeline operated by a California-based firm has been identified as the source of an oil sheen spotted off Bolsa Chica State Beach that appeared to be heading north toward the Long Beach area.

"A responsible party has been identified as DCOR LLC," the California Department of Fish and Wildlife's Spill Prevention & Response tweeted Saturday. "The sheen was observed in vicinity of their pipeline, (Pipeline 0919), which runs from Platform Eva."

DCOR is an oil and gas producer based in Oxnard.

All platform and pipeline operations in the vicinity of the DCOR pipeline have ceased, and officials are watching for "any indications of additional discharge of oil," state officials said.

It remained a priority to identify and isolate the source of the sheen, the agency continued.

"Divers will go down Tuesday to inspect the line once inclement weather improves. In the meantime, crews continue to monitor for add'l sheen & the line has been shutdown. No oiled wildlife observed; @oiledwildlife remains on standby," the agency tweeted, referring to the Oiled Wildlife Care Network.

The sheen — the second one spotted in the Huntington Beach area in about a week — was detected Wednesday roughly a mile offshore from Bolsa Chica State Beach, according to the Office of Spill Prevention and Response.

According to state wildlife officials, protective strategies were implemented at "sensitive environmental sites" as a precaution, including Talbert Marsh, Bolsa Chica wetlands, Newport Slough and the Santa Ana River.

Samples were collected Wednesday as part of the investigation. The agency reported that despite the deployment of protective booms, some tarballs came ashore Thursday in Huntington Beach.

Officials were monitoring the shoreline from Anaheim Bay to the Santa Ana River.

Meanwhile, officials in Long Beach said Thursday that they were monitoring the spill, which appeared to be traveling north.

"The size of the sheen is currently undetermined, however, on its current trajectory northbound, the San Gabriel River, Long Beach shoreline and Port of Long Beach could be impacted as early as ... Dec. 24," the statement said. "The city of Long Beach is actively looking at contingency plans for various scenarios and is prepared to clear the beaches immediately, start our own local mitigation efforts and provide further updates as needed." 

Last week, authorities responded to an oil sheen in roughly the same area but about two miles off the coast. Investigators said that sheen did not appear to be the result of a pipeline leak.

A major pipeline leak was deemed responsible for a large release of oil that occurred off the Orange County coast in early October, prompting a lengthy closure of beaches and businesses along the shoreline.