Although an investigation is still pending, emergency crews believe a backhoe excavating for a 69-in.-dia East Bay Municipal Utility District water line dinged an adjoining gas line and welding sparks triggered a fiery explosion that killed five, left four others in the hospital with moderate to severe burns, and destroyed a home. All of the victims were employees of the contractor, Livermore-based Mountain Cascade Inc. or subcontractor, Alamo-based Matamoros Welding.

The water line, which was being built to increase capacity to San Ramon from Walnut Creek, was part of a two-year improvement project that was scheduled to be completed in October, but was postponed in May when EBMUD fired the original contractor, Massachusetts-based Modern Continental Construction “for performance issues,” according to EBMUD spokesman Jeff Becerra. EBMUD hired Livermore-based Mountain Cascade, the contractor on the completed southern portion of the pipeline, in August and filed a claim with Modern Continental’s insurance company to force them to pay the costs of delay, citing low quality and lack of dedicated personnel and equipment. The litigation is still pending. Modern Continental indicated at the time that part of the reason for delay was that EBMUD did not move a gas pipeline far enough from the proposed water pipe path and it posed a safety hazard. Becerra said the site of the accident was not the same one mentioned in Modern Continental documents. “The site of the pipe that we moved was 1,500 ft away,” Becerra said. Modern Continental, which was also the subcontractor on Boston’s Central Arter/Tunnel project, did not return phone calls.

Three days after the accident, EBMUD still could not get crews back on the site to evaluate the damage and Becerra could not estimate how much longer the project would be delayed. The other three parts of the project, upgrades to the Walnut Creek water treatment plant, a pumping plant addition in Alamo, and the southern part of the pipeline along the Iron Horse Trail had been completed on schedule or were on track to be finished on time.


Sources at Houston-based Kinder Morgan Energy Partners (KMP), the operator of the gas pipeline, say because of the proximity to Bay Area refineries and alternative fuel supplies, product can be trucked to market and no supply problems are expected. KMP officials do not expect the incident will have a significant adverse financial impact on the company, but they also don’t have an estimate of how long it will take to repair the pipe.

KMP officials say they were not notified that work would be conducted within five feet of their pipeline as their agreement with Mountain Cascade required. California Occupational Health and Safety Administration and the Fire Marshall are investigating whether California’s One Call marking and notification procedures were followed. We should have a report in the next three to four weeks that looks at the communication between the water district and the pipeline company,” says Bob Gorham, supervising pipeline safety engineer for the Fire Marshall’s office. CAL/OSHA representatives say the investigation could take as long as six months. If it is found that these rules were not followed, the fine could be $50,000 and open the company to liability issues.

Mountain Cascade CEO Mike Fuller stressed in a written statement that, “there has been a lot of speculation and inaccuracy in the reporting of this accident” and the cause is still under investigation.

According to reports from the California Dept. of Industrial Relations, Mountain Cascade, a large northern California contractor also working on the Hesperian Booster Pump Station in Hayward and the Rinconada Reservoir in Los Gatos, has had two deaths in the last five years. The most recent was in March 2004 when a 31-year-old worker was crushed while unloading a sewer pipe. Mountain Cascade was fined $36,000 after investigators determined the load was not properly secured.

The Nov. 9 incident was California's first fatal accident involving a liquid petroleum pipeline since 1989, when two people were killed at a train derailment site. The U.S. Dept. of Transportatio's Office of Pipeline Safety reported that the average number of accidents per year for liquid pipelines has been decreasing over the last 10 years. “Third party incidents are still the number one reason for pipe failure,” says Damon Hill, OPS public affairs specialist.

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fatal gas pipeline explosion on Nov. 9 further delayed an already controversial $24.5-million water project in San Francisco’s East Bay.