External corrosion on an oil pipeline near Santa Barbara, Calif., was the main cause of last year’s oil spill on California’s coast, federal investigators said.
The finding came in a preliminary report released Wednesday by the Transportation Department’s Pipeline and Hazardous Materials Safety Administration (PHMSA).
Investigators found that Plains All American Pipeline did not find the extreme corrosion on the pipeline near the beach in Santa Barbara County on previous inspections.
Shortly before the May 19, 2015, spill, pumping in the line was shut down, the report said. When it was turned back on, the oil surged, breaching the corroded metal in a 2-foot section of the line.
The PHMSA’s inspection of the line found numerous other worrisome corroded sections, including two in which the metal was 80 percent corroded.
The spill dumped 140,000 gallons of oil onto the beach and into the ocean, near the site of a major 1969 oil spill disaster off the coast.
Oil and tarballs washed up on beaches up to 100 miles away, including in Los Angeles.