CONSOLIDATED EDISON CO OF NEW YORK

Incident Narrative

ON SEPTEMBER 27, 2016, AT 06:36, CON EDISON'S GAS EMERGENCY RESPONSE CENTER (GERC) RECEIVED A REPORT FROM ITS CUSTOMER OPERATIONS CALL CENTER THAT A MEMBER OF THE PUBLIC HAD CALLED IN A STRONG OUTSIDE GAS ODOR ON TIBBETT AVENUE BETWEEN WEST 234TH AND WEST 236TH STREETS IN THE BRONX. AT 06:37, A DISPATCHER WITH THE FIRE DEPARTMENT OF THE CITY OF NEW YORK (FDNY) CALLED CON EDISON'S GERC AND REPORTED THAT THE FDNY WAS ON LOCATION FOR AN OUTSIDE GAS ODOR IN THE AREA OF A PRIVATE HOUSE LOCATED AT 300 WEST 234TH STREET. CON EDISON'S GERC DISPATCHED A LEAK SURVEY MECHANIC TO THE LOCATION AT 06:39. AT 06:45, THE FDNY REPORTED EVACUATING THE PRIVATE HOUSE AT 300 WEST 234TH STREET BECAUSE OF THE GAS ODOR. A MULTIPLE RESOURCE RESPONSE EVENT (CODE MURRE) WAS THEN INITIATED BY CON EDISON AND ADDITIONAL PERSONNEL - A SUPERVISOR AND MECHANIC FROM CON EDISON'S GAS DISTRIBUTION SERVICES (GDS) DEPARTMENT - WERE DISPATCHED TO THE LOCATION BY THE GERC. THE GERC THEN CALLED THE FDNY TO PROVIDE INFORMATION CONCERNING THE LOCATION OF THE CURB VALVE, AT WHICH TIME THE FDNY REPORTED THAT IT HAD ALREADY CLOSED THE CURB VALVE ON THE GAS SERVICE LINE SUPPLYING 300 WEST 234TH STREET. A FIELD OPERATIONS PLANNER WITH CON EDISON'S GAS EMERGENCY RESPONSE GROUP (ERG) WAS DISPATCHED AT 07:05. AT 07:08, THE FDNY REPORTED THAT IT HAD REQUESTED ASSISTANCE FROM THE NEW YORK CITY POLICE DEPARTMENT (NYPD) BECAUSE OF A POSSIBLE DRUG LAB AT THE LOCATION. CON EDISON'S LEAK SURVEY MECHANIC ARRIVED AT 07:14. HE ENTERED THE BASEMENT OF 304 WEST 234TH STREET AND, USING A GAS MEASUREMENT INSTRUMENT, DETECTED NO GAS-IN-AIR IN THE AREA OF THE GAS SERVICE POINT OF ENTRY. THE LEAK SURVEY MECHANIC THEN ENTERED THE BASEMENT OF 300 WEST 234TH STREET AND, USING A GAS MEASUREMENT INSTRUMENT, DETECTED NO GAS-IN-AIR IN THE AREA OF THE GAS SERVICE POINT OF ENTRY. THE GDS MECHANIC AND GDS SUPERVISOR ARRIVED AT 07:26 AND 07:28, RESPECTIVELY. TOGETHER WITH THE LEAK SURVEY MECHANIC, THEY ENTERED THE BASEMENT OF 300 WEST 234TH STREET TO INVESTIGATE AND VERIFY SHUTDOWN OF THE GAS SERVICE. WHEN THE CON EDISON ERG FIELD OPERATIONS PLANNER ARRIVED AT 07:31, HE JOINED THE OTHER CON EDISON RESPONDERS IN THE BASEMENT OF THE BUILDING. MOMENTS LATER, AT 07:32, THE GDS SUPERVISOR AND ERG FIELD OPERATIONS PLANNER REPORTED THAT AN EXPLOSION OCCURRED ON THE SECOND FLOOR OF THE BUILDING AND THAT ALL CON EDISON EMPLOYEES WERE ACCOUNTED FOR. TWO OF THE FOUR CON EDISON EMPLOYEES IN THE BASEMENT AT THE TIME OF THE EXPLOSION SUSTAINED MINOR INJURIES. ALL FOUR CON EDISON EMPLOYEES WERE TRANSPORTED TO MONTEFIORE MEDICAL CENTER FOR EVALUATION. THE AREA IS SUPPLIED BY A 4-INCH HIGH-PRESSURE POLYETHYLENE (HPPE) GAS MAIN, WITH A 1-INCH HPPE BRANCH SERVICE SUPPLYING 300 AND 304 WEST 234TH STREET. FOUR MAIN VALVES WERE CLOSED TO ISOLATE GAS SUPPLY TO THE AREA, WHICH INTERRUPTED GAS SERVICE TO NINE RESIDENTIAL CUSTOMERS. A RECENT LEAK SURVEY OF THE AREA, CONDUCTED A WEEK PRIOR TO THIS INCIDENT ON SEPTEMBER 20, 2016, FOUND NO LEAKS. ODORANT LEVELS AND DISTRIBUTION SYSTEM PRESSURE SUPPLYING THE AREA WERE CHECKED AFTER THE INCIDENT AND FOUND TO BE WITHIN ACCEPTABLE RANGES. MULTIPLE MEDIA OUTLETS WERE ON LOCATION. A FDNY BATTALION CHIEF WAS STRUCK AND KILLED BY DEBRIS PROPELLED BY THE EXPLOSION. OTHER INJURIES WERE REPORTED. THE NYPD ISOLATED THE AREA AS A CRIME SCENE. MULTIPLE MUNICIPAL AGENCIES WERE ON LOCATION. NYSDPS, NYCDEP, AND USDOT WERE NOTIFIED. NYSDPS SURESH THOMAS WAS NOTIFIED AND RESPONDED TO LOCATION. THE FIRE MARSHAL INVESTIGATION CONCLUDED THAT THE EXPLOSION WAS CAUSED BY AN ACCIDENTAL IGNITION OF NATURAL GAS TRAPPED IN THE SECOND-FLOOR BEDROOMS. INVESTIGATORS FOUND THAT THE TENANTS IN CONTROL OF THE HOUSE HAD SEALED SECOND-FLOOR BEDROOM WINDOWS WITH FOAM BOARDS TO CONCEAL A MARIJUANA GROW OPERATION. ALTHOUGH THE GAS LEAK WAS ISOLATED WITH SERVICE TURNED OFF, THE FOAM BOARDS ON THE SECOND FLOOR PREVENTED EMERGENCY RESPONDERS FROM VENTING ACCUMULATED GAS, WHICH SUBSEQUENTLY EXPLODED.