SOUTHERN CALIFORNIA GAS CO

Incident Narrative

ON JANUARY 20, 2017, AT APPROXIMATELY 15:28, SOCALGAS COMPANY (SCG) WAS NOTIFIED OF AN EXPLOSION THAT OCCURRED AT 1748 S. MOUNTAIN AVENUE, UNIT A, ONTARIO, CA 91762. ACCORDING TO THE ONTARIO FIRE DEPARTMENT, AN INDIVIDUAL WENT INTO THE GARAGE TO SMOKE A CIGARETTE, AND THE EXPLOSION OCCURRED AFTER HE LIT A LIGHTER. THE INDIVIDUAL WAS TRANSPORTED TO ARROWHEAD REGIONAL TO BE TREATED FOR HIS INJURIES. SCG FIRST RESPONDERS ARRIVED TO THE SCENE AND REPORTED GAS INDICATIONS AT THE MSA. CONSEQUENTLY, A STEP II LEAK INVESTIGATION WAS CONDUCTED SUCCESSFULLY. PRESSURE AND LOCK-UP WAS WITHIN TOLERANCE AND THE METER WAS HARD CLOSED. UNDERGROUND SAMPLES WERE TAKEN TO DETERMINE THE LOCATION OF THE LEAK. LEAK INDICATIONS WERE FOUND AT THE MAIN TO MAIN TIE-IN, WHICH IS APPROXIMATELY 15 FT FROM THE GARAGE WHERE THE EXPLOSION OCCURRED. AFTER FURTHER INVESTIGATION, THE LEAK WAS FOUND ON A CRACKED ALDYL-A TEE FITTING AT THE MAIN TO MAIN TIE-IN. WE FOUND A HAIRLINE CRACK APPROXIMATELY 1 1/2 INCHES LONG ON ONE OF THE ARMS OF THE 'TEE'. THE CRACKED FITTING WAS FOUND UNDERGROUND WITH OTHER SUBSTRUCTURES, YET LOCATED DIRECTLY BELOW A CONCRETE ELECTRICAL BOX OWNER BY GTE. GTE WAS AN OLD TELCO COMPANY NOW OWNED BY FRONTIER. THE EDGE OF THE CONCRETE BOX, LINED UP WITH THE LOCATION OF THE CRACK. THE FITTING AND SEVERAL FEET OF PIPE WERE REPLACED AND SECURED AS EVIDENCE BY THE GAS COMPANY. UPDATED 3/3/2019 - FURTHER INVESTIGATION SHOWED THE IDENTIFIED LEAK CAUSE WAS ""EXCESSIVE BENDING STRAIN"". FOR ANY FURTHER QUESTIONS, CONTACT KHOA LE AT (626) 893-4536.