The employer of welders killed and disabled in a pipeline explosion two years ago in Walnut Creek, Calif., is urging Gov. Arnold Schwarzenegger to sign a worker-safety bill, reports the Walnut Creek-based Contra Costa Times. The bill, which would require certification for workers charged with marking the locations of dangerous underground utilities when excavation work occurs near them, was written largely in response to the Nov. 9, 2004 incident in which five men died and four suffered severe burns.

"I am writing as an accident victim, devastated business owner, employer and father. One who lived the events first hand that causes this Senate bill to be written," Michael Matamoros of Oakley, Calif. wrote the governor in a letter dated Sept. 14.

State safety officials blamed the explosion on workers for pipeline owner Kinder Morgan Energy Partners of Texas who failed to mark a sharp bend in a high-pressure petroleum line. A backhoe operator digging a ditch for a water main hit it.

Three of the dead and two of the burn victims worked for Matamoros Pipelines Inc. They were welding the water main when the backhoe, working just ahead of them, hit the petroleum pipe.

The governor has yet to sign the bill.