High Tide Bursts Dam, Takes Oil Into Marsh : Environment: Water bearing oil residue invades the Talbert Marsh in Huntington Beach, posing a threat of long-term damage to the wildlife habitat.

After work crews battled the elements for 2 1/2 weeks to keep oil from entering a sensitive wildlife preserve, pounding surf and high tides burst a protective dam and sent oil residue from the Feb. 7 spill into the Talbert Marsh wetlands, officials said.

Just how much oil invaded the area was a matter of dispute Sunday. Officials handling the spill cleanup generally agreed, however, that it was enough to pose a long-term threat to the area.

Contamination of the sensitive wildlife preserves along the coast was the event officials feared most after the oil tanker American Trader suffered a gash in its hull off Huntington Beach and spilled 394,000 gallons of crude oil into the sea.

Workers had built earthen dams and set up sandbags and containment booms to protect the Huntington Beach Wetlands, the Bolsa Chica Wetlands and a marshy preserve in Upper Newport Bay.

Oil that enters a wetlands can permeate it so deeply that it may take months and even years to be cleaned, said Victor Leipzig, a Huntington Beach city planner and coordinator of the volunteer efforts. The Huntington Beach Wetlands, part of the Pacific Flyway, are a refuge for migratory waterfowl and is the home of a number of endangered species.

Shortly before 9 a.m. Sunday, a six-foot tide strengthened by seven-foot waves created a surge of water that went racing up the Talbert Channel leading to the Huntington Beach Wetlands. The onslaught destroyed an eight-foot earthen dike that had been reinforced by hundreds of sandbags. A dozen absorbent booms placed on both sides of the dike were also shoved aside. The dike had been designed to withstand an average tide, but Sunday’s tide was six feet above average, and the highest of the month, Huntington Beach Fire Chief Ray Picard said.

The earthen dam collapsed in full view of scores of workers who were cleaning rocks in the channel.

But officials had differing assessments of the extent of the damage caused by that break.

Huntington Beach Mayor Thomas J. Mays said late Sunday that most of the oil washed back to sea with the tide. He estimated that all that remained was about 10 gallons, spread in a sheen six-feet wide along the marsh.

“We have been very fortunate,” said Mays, who made his estimate after taking a helicopter tour.

Still, he said, “any spill occurring in a wetlands is sensitive.”

But Leipzig disagreed with Mays’ estimate, saying that in his survey, done well after the dam collapse, there was a sheen of oil all over the 25-acre marsh.

“My guess is it has to be a lot more than 10 gallons,” Leipzig said. “There’s still a lot of oil in the wetlands. All seven islands in the wetlands were surrounded by bathtublike oil rings. My assessment is there is a real problem.”

Picard said untold damage had been done.

According to early estimates, Picard said, mousselike globs of brown oil had covered 5% of the the Talbert Marsh area and that an oily sheen was seen over much of the rest of it before tides pulled it back to sea.

“It’s a severe blow,” Picard said. “From an environmental standpoint, this is the worst that has happened since the spill.”

Officials of British Petroleum, whose oil the tanker was carrying, said Sunday that tests were being performed on the oil in the wetlands to determine whether it had come from the vessel. Company officials said the oil could have come from another source upstream. The firm had been involved in what it described as its final mop-up of the major spill when Sunday’s setback occurred.

“There is some concern that this (oil) may have been from an upstream source,” said British Petroleum spokeswoman Marcia Meermans said. “Nonetheless, we have people on scene.”

Environmentalists and city officials at the scene said the oil appeared to have come from the spill.

“Of course it’s possible the oil came from upstream, but I’m extremely skeptical,” Leipzig said. “I think the volume of oil in the marsh is indicative that it came from a major source.”

Louann Murray, a biology consultant for the Huntington Beach Conservancy environmental group, took a survey of the Talbert Marsh Sunday morning. She said that she could see oil-blackened rocks, mud and vegetation throughout the preserve but that it might take years before the full extent of the damage can be ascertained.

The area was reopened last year as a wetlands after having been closed for more than 30 years. It had been partially filled in the 1950s. There is a $1-million state and local project now in its early stages to restore the wetlands to their original state. The restoration is expected to take years.

The region is home to crabs, fish, shore birds and coastal plants. Among the creatures are endangered species that include the brown pelican, least tern and two mating pairs of the Belding’s Savannah sparrow.

“This is just a baby wetlands, and it’s just been trashed,” Murray said. “There was a foot thick of chocolate-mousse crude piled up outside the dam, and when it broke all that went into the wetlands.”

Huntington Beach Fire Department Battalion Chief Dennis Groat said the oil backed up outside the dam at the time of the collapse was crude that had been steam-cleaned off rocks in recent days and oil that the tides off the local beaches had been pulling back to sea beaches.

Groat and other officials had a difficult time tallying the damage to wildlife Sunday. Volunteers and cleanup crews were using boats to search the seven man-made islands in the preserve.

“So far, there is no evidence of any tremendous destruction of wildlife yet,” Leipzig said. “But this is a situation where we may not know the effects of the toxicity for even years to come. From a cleanup point of view, there is no cleaning of oil from vegetation.”

Shortly after the dam burst, workers found two oil-covered birds, which were taken to a wildlife treatment center at Terminal Island.

Workers Sunday said they could see several other birds coated with light amounts of oil. In addition, there were scores of oil-blackened mussels clinging to the rocks along the Talbert Channel.

“When I got here this morning, the fish were jumping like crazy trying to get out of the oil,” Murray said.

The marsh is so new and fragile, she said, that the wildlife food chain could suffer long-lasting damage. Clumps of pickle weed, which is a food source for several species, including the Belding’s Savannah sparrow, is heavily contaminated with oil, she said.

Pete Dalquist, an Orange County engineer who designed the dam, said he and other officials had been forewarned Saturday about the high tides predicted for Sunday but that they had no idea that the surf would be so strong.

As tidal waters receded late Sunday morning, work crews supervised by the Orange County Flood Control Agency moved bulldozers and other heavy equipment into place to rebuild the dam. Officials of British Petroleum, which has spent more than $13 million cleaning beaches, jetties and tidepools after the spill, also rushed a suction truck into place to vacuum oil from the marsh.

Officials at the scene could not estimate Sunday how long it would take to clean up the latest mess.

“It will put us a little behind schedule,” said British Petroleum’s Meermans.

It had been hoped that the 10 miles of closed beaches between Huntington Beach and Newport Beach could be reopened soon, but there was no indication Sunday when that might happen.

Times correspondents Len Hall and Tom McQueeney contributed to this report.