Denver, Colorado 2021-10-07 20:34:32 –
MATTHEW BROWN, BRIAN MELLEY, STEFANIE DAZIO
Huntington Beach, CA (AP) — A video of a ruptured pipeline spilling tens of thousands of gallons of crude oil from Southern California shows a thin crack along the top of the pipe. This may indicate a slow leak that was initially difficult to detect. The expert said Thursday.
A narrow 13-inch (33-centimeter) long gouache could explain why signs of oil slicks were seen on Friday night, but they said the spill escaped detection by pipeline operators until Saturday morning. ..
“In my experience, this suggests a very difficult leak for remote and quick decisions,” said Richard Cuprewitz, a private investigator and consultant for pipeline accidents. .. “This type of opening is in a 17 mile (27 km) long underwater pipe and is very difficult to find remotely. These crack type releases are low rate and can last for quite some time. There is sex. “
When a pipe suffers a catastrophic failure, the damage is usually much greater. In the industry, it is called a “fish mouth” rupture because it has a wide gap like a fish mouth.
Houston-based Amplify Energy, which owns and operates three offshore oil platforms and a pipeline in southern Los Angeles, spills until workers detect oil luster on the surface of the water at 8:09 on Saturday. He said he didn’t know it was.morning
The cause of the spill is being investigated by many agencies as it continues to be purified along the miles of the Orange County coast south of the ports of Los Angeles and Long Beach.
On Thursday, the Coast Guard slightly revised the spill estimates to at least about 25,000 gallons (95,000 liters) and 132,000 gallons (500,000 liters) or less.
The Coast Guard said Thursday that it was investigating an incident with another agency as a “serious marine accident” due to possible vessel involvement and damage of more than $ 500,000. He said he would decide whether criminal accusations, civil penalties, or new laws and regulations were needed.
Investigators are investigating whether a ship waiting to unload cargo has anchored and bent the pipeline.
Coast Guard investigators boarded the giant German-flagged container ship Rotterdam Express on Wednesday to determine if it was involved in the spill. Rotterdam was the ship that anchored closest to the pipeline last week.
Hapag-Lloyd, the shipping company that operates the ship, confirmed on Thursday that investigators boarded the ship while moored at Oakland Port in San Francisco Bay. According to Nilshaupt, a spokesman for Hapag-Lloyd headquarters in Hamburg, Germany, the Coast Guard interviewed the captain and crew and provided access to a logbook showing the location of the ship.
The Coast Guard then called the company to inform them that Rotterdam was not under surveillance for the spill, Haupt said. The ship was allowed to leave Auckland and headed for Mexico.
According to investigators, the spill occurred about 5 miles (8 kilometers) offshore and about 98 feet (30 meters) deep. According to Martyn Willsher, CEO of Amplify, a 4,000-foot (1,219-meter) section of the pipeline has moved 105 feet (32 meters) and bent back like a bow strap.
Jonathan Stewart, a professor of civil and environmental engineering at the University of California, Los Angeles, said he was surprised that the damage was not so serious given how far the pipes had moved.
“My first reaction when I heard that I had moved so far was notable that it was even totally intact,” Stewart said.
The question remains as to when the oil companies learned that there was a problem and the spill was delayed.
Foreign vessels moored in the waters off Huntington Beach reported to the Coast Guard that they had seen more than two miles (3.2 km) of luster shortly after 6 pm. Satellite images taken by the European Space Agency indicate that oil slicks may have formed in the surrounding area. 7 pm. This was reported to the Coast Guard on Saturday at 2:06 am after a review by US National Oceanic and Atmospheric Administration analysts.
Federal pipeline security regulators set the time of the incident on Saturday at 2:30 am, but the company did not shut down the pipeline until 6: 1 am and leaked to the Coast Guard until 9:07 am Says he did not report. State regulations require immediate notification of a spill.
Wilshere, who asked questions with the Coast Guard and other officials for four days, did not appear at a press conference on Thursday. Other officials declined to explain his absence.
The types of cracks seen in the Coast Guard videos are large enough that some oil can escape and trigger low-pressure alerts, Kuprewitz said. However, he said, because the pipeline was operating at relatively low pressure, the control room operator could simply have cleared the alarm because the pressure was not so high at the start.
Ramanan Krishnamurti, a professor of petroleum engineering at the University of Houston, said the pipeline could have been leaked for several days before it was discovered.
“If you have a big crack or a big hole, you can see that there is a big leak because the pressure drops significantly,” he said. “If you have such a hairline crack, this probably lasted for a couple of days.”
The fact that the San Pedro Bay line is still covered with concrete in the video is another sign that oil is likely to be leaking at a low rate. A serious breach of high-voltage lines will blow concrete, according to Cuprewitz.
The second underwater video released on Thursday showed a wider view of the bends in the pipeline. A long depression of sand can be seen crossing one side of the pipe at a bend, but does not seem to continue to the other side of the line.
“That’s pretty obvious,” said Krishna moorti. “There seems to be something dragged into the sand that may have affected the pipeline.”
But he continued to be confused that the leak was coming from a rift rather than a large rift, assuming he had hit an anchor or other object.
The cracks suggest that the pipes installed in 1980 probably withstood the first impact, but that corrosion weakened over time and made them more susceptible to failure, Krishnamurti said. In other words, Amplify takes some responsibility in case of failure.
The Coast Guard video does not reveal the condition of the 0.5-inch thick steel pipe underneath, as the lines are covered with concrete (a means of reducing weight on the seabed).
Federal safety investigators can conduct a scrutiny to cut out damaged parts of the pipe and remove it to look for signs of corrosion, metal fatigue, or other anomalies that are vulnerable to failure. increase. The test should also reveal if the cracks have grown over time, Kuprewitz said.
Associated Press writers Michael Biesecker and Michael Balsamo contributed from Washington. Michael R. Blood contributed from Los Angeles.
Small crack in pipeline may have delayed oil spill detection – The Denver Post Source link Small crack in pipeline may have delayed oil spill detection – The Denver Post