TRANSCONTINENTAL GAS PIPE LINE COMPANY

Incident Narrative

ON 2/8/2022 AROUND 5:00 PM ON CALL PERSON RECEIVED A CALL FROM GAS CONTROL ABOUT A SMELL OF GAS AT 616 SUSQUEHANNA ROAD AMBLER, PA UPPER DUBLIN TOWNSHIP. EMPLOYEE ARRIVED ON SITE AROUND 6:15 PM. WHEN HE TURNED ON FLAME I (GAS DETECTOR) IT WENT OFF IMMEDIATELY. EMPLOYEE CALLED HIS SUPERVISOR AROUND 6:40 PM. SUPERVISOR ADVISED HIM TO CALL PECO (LOCAL LDC IN AREA) TO CHECK FOR LEAKS ON THEIR SYSTEM WHICH IS WITHIN 20 FT. SUPERVISOR ARRIVED ON SITE AT 8:30 PM. AT 4:00 AM ON 2/9/2022 PECO DETERMINED IT WASN'T THEIR SYSTEM LEAKING. EMPLOYEE ON SITE CALLED SUPERVISOR RIGHT AWAY. WILLIAMS CREW WAS ON SITE AT 7:00 AM TO HAND DIG PIPELINE AND DISCOVERED IT WAS THE FLANGE LEAKING AT 9:20 AM. SUPERVISOR CALLED SOC AT 9:30 AM ON 2/9/2022. LINE WAS TAKEN OUT OF SERVICE AND DRAWN DOWN FROM 638 PSI TO 90 PSI. WILLIAMS CREW TRIED TO TORQUE BOLTS WITH NO LUCK. ON 2/10/2022 WILLIAMS CREW BROUGHT IN A BIGGER TORQUE GUN IN THAT WOULD GO HIGHER WITH NO LUCK. AT THIS POINT, WILLIAMS DETERMINED PROPERTY DAMAGE WOULD EXCEED THE REPORTABLE LIMIT OF $122,000 AND NOTIFIED THE NRC. DECISION WAS MADE TO CUT OUT FLANGE. 2/11/2022 LINE WILL BE BLOWN DOWN TO 0 PSI. REPLACEMENT INSULATING FLANGE DID NOT ARRIVE ON SCHEDULE SO CREWS INSTALLED A 24"" PUP AND RETURNED THE LINE BACK IN SERVICE ON 2/12/2022 AROUND 5:00. THE INSULATING FLANGE WAS REVIEWED AND THE FAILURE WAS IDENTIFIED TO BE DUE TO A FAILURE OF THE O-RING. A NEW INSULATING FLANGE WAS INSTALLED. THE INSULATING FLANGE THAT FAILED WAS A CLAMP ON STYLE FLANGE. THESE ARE NOT IN USE ELSEWHERE ACROSS THE WILLIAMS SYSTEM AND THE SAME O-RING FAILURE MECHANISM IS NOT A CONCERN DUE TO THE LACK OF OTHER SIMILAR INSULATING FLANGES.