SOUTHERN CALIFORNIA GAS CO

Incident Narrative

ON OCTOBER 15TH, 2014, SEVERAL CALLS WERE RECEIVED REPORTING NO GAS FROM THE PALMDALE AREA. NO INJURIES OR PUBLIC DAMAGE RESULTED FROM THIS INCIDENT. ALL CUSTOMERS WHOSE SERVICES WERE INTERRUPTED HAVE BEEN RESTORED. INVESTIGATION OF THE INCIDENT SHOWED THAT THE REGULATOR STATION SUPPLYING GAS TO THE AFFECTED CUSTOMERS WAS FED FROM TWO GAS TRANSMISSION LINES (LINE 235 AND LINE 335). FURTHER INVESTIGATION SHOWED A PIN OFF TEE ON THE TRANSMISSION LINE AND INSTRUMENTATION DIAGRAM OF LINE 235 FEEDING THE SUPPLY LINE TO THE REGULATOR STATION. A PIN OFF TEE IS NORMALLY BURIED IN THE OPEN (PIN RAISED POSITION) AND CANNOT BE OPERATED (PIN LOWERED) UNLESS EXCAVATED TO PROVIDE ACCESS TO THE PIN BY REMOVING A CAP ON THE PIN OFF TEE. THERE WAS NO PIN OFF TEE ON LINE 235 AND THE SUPPLY LINE TO THE REGULATOR STATION WAS ACTUALLY CONNECTED TO LINE 235 WITH A CLOSED CURB VALVE TEE INSTEAD. WHEN THE LINE 335 FEED WAS ISOLATED AND DEPRESSURIZED, THE FEED TO THE REGULATOR STATION WAS LOST RESULTING IN GAS OUTAGES. INITIALLY WHEN THE LINE 235 VALVE WAS CLOSED, THAT PIPELINE WAS NOT BLOWN DOWN AND THE VALVE BYPASSED ENOUGH THAT UPON CHECKING THE INLET FEED TO THE REGULATOR STATION IT APPEARED THE LINE 235 PIN OFF TEE WAS OPEN. THIS INCIDENT WAS REPORTED TO THE DOT AND CPUC WHEN ESTIMATED COSTS OF REPAIR AND RECOVERY WERE ANTICIPATED TO EXCEED $50,000 THRESHOLD.