Calm Waters Help Crews Finish Oil Spill Cleanup : Environment: So far, biologists have found little sign of damage from the leak of 10 to 50 barrels of crude off the coast of Oxnard.

Relatively calm seas and moderate winds allowed crews to finish their cleanup on Sunday of a five-mile-long oil slick off the coast of Ventura County, caused by a weekend rupture of an offshore oil pipeline that spilled between 420 and 2,100 gallons of crude into the sea.

Lt. Angel Raton of the California Department of Fish and Game said calm conditions prevented the slick from moving onshore and gave cleanup crews an opportunity “to go out in boats and scoop the oil off the surface.”

By Sunday morning, Unocal had retrieved most of the oil that leaked from its Platform Gina on Friday and asked government permission to cease its cleanup efforts, said company spokesman James H. Bray. The state Department of Fish and Game, the U.S. Minerals Management Service and the Coast Guard granted permission to shut down shortly after noon.

“We are in a wind-down situation,” Bray said. Crews collected the few remaining pockets of heavy crude Sunday, he said, leaving a very light coat of oil on a half-mile-square patch of ocean about seven miles from shore.

“That sheen is almost unrecoverable,” he said. The last vestiges should evaporate or dissipate within days and never reach shore, he said. “We will continue to have people on the beach--just monitoring--for a couple of days.”

Meanwhile, state and federal authorities continued to investigate the cause of the spill, which occurred when a work boat ripped open an oil pipeline on the platform four miles southwest of Oxnard.

Lt. Reed Smith of Fish and Game said Unocal may face civil or criminal charges under state laws that hold oil companies liable for spills. But he said the investigation might take as long as two months before any decision is made to file charges.

“The state attorney general would handle any civil litigation, and the county district attorney’s office would handle any criminal charges,” Smith said.

Cleanup crews spent the weekend containing the slick about six miles off ecologically sensitive habitats on Anacapa Island and Mugu Lagoon on the mainland. After unfurling and dragging oil-containment booms--self-inflating polyurethane fences used to corral oil at sea--workers removed the oil from the ocean surface with mechanical skimmers and pumped it into tanks.

So far, biologists have found little sign of environmental damage. Ventura County sheriff’s deputies discovered one oiled cormorant Sunday off Point Mugu and animal control authorities retrieved the bird for washing, Raton said. Biologists continued to patrol the beach in search of other fouled birds, he said.

The relatively small spill occurred about 2 p.m. Friday, when a work boat severed a 10-inch Unocal pipeline that carries 1,250 barrels of oil a day from the platform to shore.

The boat was dragging a grappling hook to retrieve an anchor chain that had dropped from a buoy near the platform. The 197-foot-boat snagged the pipeline about 200 yards from the platform and pulled on it until it snapped on one of the platform’s legs, Unocal officials said.

Automatic sensors quickly shut off the pipeline’s pumps, preventing the escape of more oil than the 10 to 50 barrels estimated by Unocal. A barrel is 42 gallons.

Several area groups joined the cleanup, including Clean Seas, a nonprofit cooperative financed by 19 area oil companies. Clean Seas sent out two vessels and several small boats, Assistant Manager John R. Herring said.

Also included in the efforts were seven boats provided by the Ventura County Fishermen’s Oil Response Team, a special reserve force that helps protect the Channel Islands and the coastline in Ventura, Santa Barbara and San Luis Obispo counties.

Fishermen have a special interest in protecting these waters, coordinator Michele Sojka said.

“That is their livelihood out there,” she said.