A federal report released Wednesday found that a California pipeline suffered from corrosion before spilling as many as 2,500 barrels of crude near Santa Barbara last month.
Preliminary findings released by the Department of Transportation identified four areas of the ruptured line that showed “pipe anomalies requiring immediate investigation and remediation.”
The DOT said that a survey of the Plains All American operated Line 901 by third-party inspectors “revealed metal loss of approximately 45% of the original wall thickness in the area of the pipe that failed on May 19.”
“Third-party metallurgists in the field estimated that corrosion at the failure site had degraded the wall thickness to an estimated 1/16 of an inch (.0625″),” the report said.
Inspectors from the Pipeline and Hazardous Materials Safety Administration also noted “general external corrosion of the pipe body during field examination of the failed pipe segment” and observed “three repairs” near the line’s failure site made after 2012.
According to the LA Times, Plains All American conducted an internal inspection of the Line 901 before the spill but did not receive the preliminary results until days after the rupture.
An internal pipeline inspection conducted by Plains found the line’s wall was thicker than the measurements included in the report.
The company said it is working with federal inspectors to understand the differences between the findings and identify the cause of the spill, according to the LA Times.
Line 901 pipeline ruptured on May 19 and released an estimated 101, 000 gallons of crude around Refugio State Beach.
Plains All American was able to shut down Line 901 about 30 minutes after detecting pressure irregularities and also blocked a nearby culvert to stop crude from escaping into the ocean.
Despite the rapid response, the spill polluted a four mile stretch of beach and created oil slicks that extend about nine miles along the coastline.
As of last week, cleanup crews had recovered about about 20 percent of the spilled crude.
Plains has also voluntarily shutdown Line 903 that is connected to the failed pipeline.
Plains CEO Greg Armstrong told Reuters that the company has boosted spending on pipeline maintenance and integrity by three fold since 2007.
California Attorney General Kamala Harris told CNN that her office is examining the evidence in collaboration with Santa Barbara District Attorney Joyce Dudley.
“We’re going to go where the evidence takes us,” Harris said.