COLUMBIA GAS TRANSMISSION, LLC

Incident Narrative

ON 7/24/17 A GAS RELEASE OCCURRED ON PIPELINE V-243 A TRANSMISSION CARBON STEEL 6"" DIAMETER PIPELINE LOCATED IN STARK COUNTY, OHIO. LINE V-243 IS A SIDELINE CONNECTION TO LINE V. A COMPANY CONTRACTOR WAS REMOVING THE BRIDAL SETTING THAT GOES AROUND THE MAINLINE VALVE TO LINE V AND THE GAUNTER REGULATOR STATION (RS) 02345 TO REPLACE WITH A NEW PREFABRICATED BRIDAL SETTING. THE OLD 4"" PIPELINE WAS HAND SPOTTED AND THEN EXCAVATED EXPOSING BOTH THE TOP AND SIDES OF THE PIPELINE GOING INTO THE M&R BUILDING. SINCE WORK WAS NOT SCHEDULED ON LINE V-243 THIS PIPELINE WAS NOT EXPOSED. LINE V-243 RUNS PARALLEL TO THE 4"" DIAMETER PIPELINE THAT WAS EXPOSED AND WAS BEING REMOVED. THE PLAN WAS TO REMOVE THE 4"" PIPELINE AND THEN FINISH EXCAVATING. THE 4"" PIPELINE WAS BLOWN DOWN AND THE BOLTS FROM TWO 4"" FLANGES WERE REMOVED. THE KICK BRACE THAT WENT TO THE MAINLINE VALVE KICK BRACE WAS CUT, AND THE 4"" DIAMETER PIPE UP TO THE M&R BUILDING WAS COLD CUT. A SLING WAS CONNECTED TO THE BRIDAL SETTING TO LIFT UP THE OLD BRIDAL SETTING. WHILE LIFTING UP THE BRIDAL SETTING THERE WAS A RELEASE OF GAS PRESSURE. THE GAS RELEASE WAS COMING FROM THE 6"" PIPELINE (V-243). AFTER A SHORT TIME, THE GAS BLOWING FROM LINE V-243 UNCOVERED A 2"" KICK BRACE THAT WAS RUNNING FROM THE OLD 4"" PIPELINE TO LINE V-243 WAS DISCOVERED ABOUT 24"" BELOW GROUND. THE CONTRACTOR DID NOT COME INTO CONTACT WITH LINE V-243. LINE V-243 DEPTH OF COVER WAS 60 INCHES. ON7/25/26 CNG TRUCKS WERE CONNECTED TO LINE-243 TO MAINTAIN MARKET DELIVERABILITY WHILE LINE V-243 WAS ISOLATED TO MAKE REPAIRS. LINE V-243 WAS SHUT IN AND THE AREA MADE SAFE ON 7/25/17 AT 21:25. THREE FARM TAPS WERE TAKEN OUT-OF-SERVICE WHILE REPAIRS WERE MADE. REPAIRS CONSISTED OF REMOVING THE DAMAGE SECTION OF LINE V-243 AND REPLACING IT WITH A NEW PRE-TESTED 10.5 INCH PIPELINE IN LENGTH, 6"" IN DIAMETER, 0.280 WALL, X-52 PIPE AND NEW 6"" IN DIAMETER 90 DEGREE ELBOW, 0.280 WALL, GRADE B. LINE V-243 WAS RETURNED TO SERVICE ON 7/26/17 AT 16:26. THE 2"" KICK BRACE THAT WAS CONNECT TO LINE V-243 FROM THE OLD 4"" PIPELINE WAS REMOVED.