PACIFIC GAS & ELECTRIC CO

Incident Narrative

ON OCTOBER 21, 2017 AT APPROXIMATELY 1631 HOURS, PG&E WAS NOTIFIED OF A VEHICLE IMPACT NEAR THE INTERSECTION OF KASSON RD AND DURHAM FERRY RD, IN THE CITY OF TRACY. THE VEHICLE DROVE THROUGH THE FENCING & BOLLARDS AND STRUCK DISTRICT REG STATION TYHP-75, SPECIFICALLY THE SENSING LINES, RESULTING IN AN UNINTENTIONAL RELEASE OF GAS AND SUBSEQUENT OVERPRESSURE OF THE DISTRIBUTION SYSTEM DOWNSTREAM OF THE REG STATION. THE STATION IS FED OFF LINE 108 NEAR MILE POINT (MP) 5.70. PG&E GSR ARRIVED ON-SITE AT 1706 HOURS. PG&E M&C ARRIVED ON-SITE AND STOPPED THE FLOW OF GAS BY CLOSING THE STATION VALVES BY 1755 HOURS. THE OVERPRESSURIZATION OF THE 6-INCH PLASTIC DISTRIBUTION MAIN DOWNSTREAM OF THE REG STATION RESULTED IN A FUSION FAILURE NEAR 560 E DURHAM FERRY RD. THE FUSION FAILURE WAS FIRST REPORTED AT 1948 HOURS. APPROXIMATELY 9,500 FT OF 6-INCH PLASTIC MAIN AND 4 SERVICES WERE IMPACTED. THE SERVICES THAT WERE IMPACTED ARE 560 E DURHAM FERRY RD, 120 E DURHAM FERRY RD, 272 W DURHAM FERRY RD, AND 492 W DURHAM FERRY RD. THERE WERE NO REPORTED INJURIES, FATALITIES OR IGNITION. FOUR CUSTOMERS GAS SERVICE WAS IMPACTED. CNG TANKS WERE PROVIDED TO THE IMPACTED CUSTOMERS. THE STATION REBUILD WAS COMPLETED ON 12/20/2017. POLICE & FIRE DEPARTMENT WAS REPORTED ON-SITE. NO MEDIA WAS REPORTED ON-SITE. THIS INCIDENT WAS REPORTED TO THE DOT & CPUC DUE TO THE UNINTENTIONAL RELEASE OF GAS AND ESTIMATED DAMAGE COSTS EXCEEDING $50,000. AN UPDATE ON THE GAS FLOW STOP TIME & VOLUME WAS PROVIDED TO THE DOT (1194060) ON 10/23/17. PLEASE NOTE FOR THE PHMSA7100 REPORT THAT THE INCIDENT IS SPECIFIC TO THE VEHICLE IMPACT INCIDENT TO THE DISTRICT REG STATION. FOR PART E, THE MAOP OF THE DISTRICT REG STATION IS 720 AND OPERATING PRESSURE IS 700 PSIG. THE MAOP OF THE DISTRIBUTION SYSTEM DOWNSTREAM OF THE DISTRICT REG STATION IS 60 PSIG AND OPERATING PRESSURE IS 54 PSIG. THE DISTRIBUTION SYSTEM DOWNSTREAM OF THE DISTRICT REG STATION EXCEEDED 110% MAOP.