CONSOLIDATED EDISON CO OF NEW YORK

Incident Narrative

ON JANUARY 4, 2019, AT 14:15, THE FIRE DEPARTMENT OF THE CITY OF NEW YORK (FDNY) CALLED CON EDISON'S GAS EMERGENCY RESPONSE CENTER (GERC) AND REPORTED THAT THEY WERE RESPONDING TO A POSSIBLE GAS EXPLOSION IN THE STREET IN THE AREA OF NORTHERN BOULEVARD BETWEEN 112TH PLACE AND 114TH STREET IN QUEENS. CON EDISON'S GERC IMMEDIATELY DISPATCHED MULTIPLE PERSONNEL INCLUDING SUPERVISORS FROM ITS GAS DISTRIBUTION SERVICES (GDS) AND GAS EMERGENCY RESPONSE FORCE (ERF)/CONSTRUCTION DEPARTMENTS TO THE LOCATION. AT 14:16, CON EDISON'S GAS CONTROL GROUP REPORTED RECEIVING A LOW-PRESSURE ALARM AT GAS REGULATOR STATION GR-254, WHICH SUPPLIES THE SAME AREA. CON EDISON GDS PERSONNEL ARRIVED ON LOCATION AT 14:22 AND BEGAN INVESTIGATING. FDNY WAS ALREADY ON LOCATION AT THAT TIME. AT 14:25, ON-SITE GDS PERSONNEL REPORTED A STREET COLLAPSE IMMEDIATELY ADJACENT TO AN ACTIVE CONSTRUCTION SITE, AND THAT THE COLLAPSE HAD COMPROMISED A 24-INCH HIGH-PRESSURE STEEL GAS SUPPLY MAIN (INSTALLED IN 1936), CREATING A BLOWING GAS CONDITION WITH NO IGNITION. CON EDISON'S GERC THEN INITIATED A MULTIPLE RESOURCE RESPONSE EVENT (CODE MURRE) AND DISPATCHED ADDITIONAL PERSONNEL TO THE LOCATION FROM SEVERAL DEPARTMENTS, INCLUDING GDS, LEAK SURVEY, AND ITS GAS EMERGENCY RESPONSE GROUP (ERG). AT 14:26, CON EDISON'S GERC IDENTIFIED TWO HIGH-PRESSURE MAIN VALVES (46441 & 15123) FOR ISOLATING THE COMPROMISED 24-INCH STEEL SUPPLY MAIN. AT 14:50, GDS CLOSED MAIN VALVE 46441 BUT WAS UNABLE TO CLOSE MAIN VALVE 15123, WHICH WAS REPORTEDLY INOPERABLE. CON EDISON'S GERC THEN IDENTIFIED A BACK-UP HIGH-PRESSURE MAIN VALVE (21738), WHICH WAS CLOSED BY ON-SITE GDS PERSONNEL AT 15:42, THEREBY ISOLATING THE AFFECTED SUPPLY MAIN AND ELIMINATING THE BLOWING GAS CONDITION. THE INCIDENT RESULTED IN NO SYSTEM IMPACT OR GAS SERVICE INTERRUPTIONS. CON EDISON RECEIVED A TOTAL OF ONE-HUNDRED FIFTY-SIX (156) RELATED GAS ODOR COMPLAINTS. CON EDISON INVESTIGATED EACH COMPLAINT AND DETERMINED THEM ALL TO BE ASSOCIATED WITH THE INCIDENT. AT THE TIME OF THE INCIDENT, CON EDISON'S INITIAL CALCULATION DETERMINED THAT THE RUPTURED GAS MAIN HAD RELEASED LESS THAN THREE MILLION CUBIC FEET OF NATURAL GAS. SUBSEQUENTLY, ON JANUARY 7, 2019, BASED ON ADDITIONAL ANALYSIS, CON EDISON'S GAS ENGINEERING SYSTEM PLANNING GROUP DETERMINED THAT GREATER THAN TEN MILLION CUBIC FEET OF NATURAL GAS WAS LOST DURING THE INCIDENT (CON EDISON'S GAS ENGINEERING SYSTEM PLANNING GROUP CALCULATED THE TOTAL ESTIMATED VOLUME OF GAS RELEASED WAS 10,765 MSCF). CON EDISON NOTIFIED THE DEPARTMENT OF PUBLIC SERVICE STAFF (DPS STAFF), NEW YORK CITY DEPARTMENT OF ENVIRONMENTAL PROTECTION (NYCDEP), AND THE U.S. DEPARTMENT OF TRANSPORTATION (USDOT). MULTIPLE MEDIA OUTLETS WERE ON LOCATION DURING THE INCIDENT. MULTIPLE AGENCIES WERE ALSO ON LOCATION, INCLUDING FDNY, NEW YORK POLICE DEPARTMENT (NYPD), NEW YORK CITY DEPARTMENT OF TRANSPORTATION (NYCDOT), NEW YORK CITY EMERGENCY MANAGEMENT (NYCEM), AND DPS STAFF. THE AFFECTED SUPPLY MAIN WAS REPLACED AND RETURNED TO SERVICE BY CON EDISON ON JANUARY 19, 2019.