Coast Guard investigators say California pipeline was likely damaged up to a year before the spill
HUNTINGTON BEACH, Calif. (AP) – An undersea pipeline off the southern California coast was likely damaged by a ship’s anchor several months to a year before it ruptured and sent oil into the ocean, then on to some of the best known in the region. beaches, investigators said on Friday.
Coast Guard Captain Jason Neubauer, head of the Bureau of Investigation and Analysis, said after the first strike, it is possible that the anchors of other ships then struck the steel pipe that brought the oil to shore. from three platforms at sea. Investigators previously said much of the pipe was bent after being struck and dragged along the seabed.
It is still unclear when the thin 13-inch (33-centimeter) crack began to leak oil, and investigators will pour over a year of data on vessel movements near the area of the rupture. No vessel has been identified as suspect at this stage.
“We will be looking at every vessel movement on this pipeline and every encroachment near anchorages throughout the year,” Neubauer said.
The accident site was outside the Long Beach-Los Angeles port complex, which is the largest in the country and handles some 4,000 ships a year. Many of them come from abroad and this could complicate the process of boarding the vessels concerned by the investigation to obtain information.
The disclosure that the pipe damage could have occurred so long ago has dramatically altered what was known about the leak that sent tens of thousands of gallons of crude into the Pacific. Research that initially appeared to focus on finding a vessel could now send investigators to ports across the country to inspect numerous vessels.
It now appears that many factors played a role in the pipe failure – possible repeated anchoring impacts, stresses caused by sliding on the seabed, and corrosive forces from seawater.
Neubauer said investigators had limited their search to large freighters that would be powerful enough to move a section of pipeline from 4,000 feet (1,219 meters) to 105 feet (32 meters) across the ocean floor. He also said investigators focused on a windy storm on January 24 and 25 that could have caused problems for ships trying to anchor near the twin ports.
Investigators believe the first anchor point occurred some time after a pipeline survey a year ago that showed the line was in its original location. The extended timeline was in part based on the visible marine growth along the damaged length of the pipe that was revealed during an underwater survey. The Coast Guard previously posted a video of the breaking point and a wider view of the curved pipe.
A crack suggests that the pipe, which was installed in 1980, may have withstood an initial impact, but had been weakened over time by corrosion and became more susceptible to failure, Ramanan Krishnamoorti said, professor of petroleum engineering at the University of Houston.
Neubauer said a field of debris is visible on the seabed near the fault. Investigators will now remove this section of the pipe for laboratory analysis. The duration of the investigation was not clear.
So far, the impact on the wildfires has been minimal – 10 birds dead and 25 others recovered alive and treated – but conservationists warn that the long-term impacts could be much greater. As the cleanup continued on the shore and some beaches reopened on Friday, although the public still couldn’t get into the water.
Anchoring impacts on pipelines are relatively rare, but have caused problems in the past.
An Associated Press review of more than 10,000 reports submitted to federal regulators found that at least 17 accidents on pipelines carrying crude oil or other hazardous liquids were linked to anchor impacts or suspected anchoring impacts since 1986.
According to federal records, in some cases an anchor strike is never conclusively proven, such as the 2012 leak of an ExxonMobil pipeline in the shallow bay of Barataria in Louisiana, where a direct strike by a barge or another boat was also considered.
In others, the evidence of an anchor was evident. During Hurricane Andrew of 1992, a 30,000 pound (13,607 kilogram) anchor was dragged by a drifting drilling rig on a Texaco pipeline in the Gulf of Mexico, causing a bump that opened when the line was then restarted.
In 2003, a 7,000 pound (3,175 kilogram) anchor was found about 10 feet (30 meters) from a small spill on a Shell pipeline in the Gulf.
Captain Morgan McManus, who spent 20 years at sea before taking command of the training ship at the State University of New York Maritime College, said he would find it hard to believe that a competent crew would drop anchor near of a pipeline. If a vessel’s anchor becomes entangled in any piece of infrastructure, the operator is required by federal law to notify the Coast Guard.
“It would be a big mistake,” McManus said. “I have a bit of a hard time believing that would happen because you notice this stuff on the electronic charts. You are going to trace your position where you are going to drop the hook.
McManus said a more likely scenario is for a ship to be pulled from its position by strong waves or tides, dragging its anchor with it and snagging the pipeline. A second possibility is that the vessel underway engages its engines while raising its anchor, pulling it along the seabed.
The leak was discovered on Saturday morning, more than 12 hours after the first reports of a possible spill arrived. Although the exact size is not known, the Coast Guard slightly revised the parameters of the estimates to at least about 25,000 gallons (95,000 liters) and no more than 132,000 gallons (500,000 liters).
The Coast Guard said about 5,500 gallons (20,819 liters) of crude had been recovered from the ocean. The oil spread southeast along the coast with reports of small amounts landing in San Diego County, about 50 miles (80 kilometers) from the original site.
Amplify Energy, a Houston-based company that owns and operates three offshore oil rigs and the pipeline, said it did not know there had been a spill until its employees detected a shard of Oil on the water at 8:09 am Saturday. The leak occurred about 5 miles (8 kilometers) offshore at a depth of about 98 feet (30 meters), investigators said.
Questions remain as to when the company knew it had a problem and a potential delay in reporting the spill.
A foreign vessel anchored in the waters off Huntington Beach reported to the Coast Guard that it saw a burst of more than 2 miles just after 6 p.m. on October 1 and that evening, an Agency satellite image Space also indicated a probable oil slick, which was reported to the Coast Guard at 2:06 a.m. Saturday, after being examined by an analyst with the National Oceanic and Atmospheric Administration.
Federal pipeline safety regulators set the time of the incident at 2:30 a.m. on Saturday, but say the company did not shut down the pipeline until 6:01 a.m. – more than three hours after the outbreak of a low pressure alarm indicating a possible problem – and did not report the leak to the Coast Guard until 9:07 am Federal and state rules require immediate notification of spills.
Amplify said the line had already been shut down at 6 a.m., then restarted for five minutes for a “meter reading” and closed again. A meter reading shows the amount of oil entering and leaving the line. The company could have used this information to confirm whether the pressure change alarm went off because the line was leaking, said Richard Kuprewicz, a private pipeline accident investigator and consultant.
Associated Press reporters Brian Melley in Los Angeles and Michael Biesecker in Washington contributed.
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