Oil pipeline near Tracy spills thousands of gallons of crude

About 50 hazardous materials responders were on the scene of an oil pipeline rupture Monday along the Alameda County-San Joaquin County border near Tracy, cleaning up a spill reported to be as much as 21,000 gallons.

The leak in the underground pipe, which was reported by Shell Pipeline Co. after a line between Coalinga (Fresno County) and Martinez lost pressure Friday, was spilling crude oil into the soil but was not near any waterways where the problem would escalate. The oil release was visible on the ground in a 250-by-40-foot section, San Joaquin County officials said.

Shell officials said they have since shut down their San Pablo Bay Pipeline and have a response team on-site clearing contaminated soil and monitoring local air, water and ground conditions with local and state authorities. The effort is concentrated near Interstate 580 and West Patterson Pass Road.

The cause of the rupture has not been identified, but Shell officials said they expected it to be fixed Monday. There is no timeline for when the oil flow will be turned back on.

"Our primary focus continues to be the safety and health of the responders, for the protection of the environment and to minimize any further impact as a result of this release," Ray Fisher, a company spokesman, said in an email to The Chronicle. "We are committed to the safe and thorough response and management of this incident."

The California Regional Water Quality Control Board is leading the cleanup. Neighboring Alameda County officials reported in a filing with the Governor’s Office of Emergency Services that 500 barrels of oil had been discharged into the ground, but none into waterways.