Olympic Pipeline Co. first reported the oil to Ecology Oct. 29 after discovering a sheen on water in an excavation pit, Ecology said in a news release. The pipeline was closed that day and state and pipeline personnel responders have been monitoring the site since then to determine the source, type and location of the oil and to plan cleanup strategies.
The pipeline delivers fuel from Tesoro and Shell refineries in Anacortes to Olympic's main pipeline that runs from two refineries in Whatcom County to Portland, Oregon.
When Olympic Pipeline crews performed a test under flowing conditions on the 20-inch pipeline Monday night, they found a leak in a half-inch connection of piping associated with a mainline pump discharge valve, Ecology said in the news release. Since this investigation began, crews recovered 60 gallons of mixed diesel, jet fuel and gasoline.
Earlier Monday, investigators believed the oil was not from a pipeline or valve leak, but was part of historical contamination from spills dating back to 1988, Ecology said.
Currently the leak is secure and the 20-inch pipeline is shut down and Olympic’s 16-inch pipeline is in service, Ecology said. Crews plan to make repairs on the valve and get the pipeline back in operation. Meanwhile, response crews will continue to work with state officials to remediate any remaining traces of hydrocarbons in the soil at the site.