INTERMOUNTAIN GAS CO

Incident Narrative

AT 15:32 ON JANUARY 16, 2020, THE IDAHO FALLS FIRE DEPARTMENT REPORTED A NATURAL GAS LEAK NEAR THE SOUTHBOUND ON-RAMP OF I-15 AND BROADWAY ST. IN IDAHO FALLS, ID. INTERMOUNTAIN GAS COMPANY (IGC) FIRST RESPONDERS ARRIVED AT 15:50 AND CONFIRMED AN UNDERGROUND GAS LEAK. ONCE THE EXACT LOCATION WAS PINPOINTED BY IGC CONSTRUCTION AND LEAK SURVEY PERSONNEL, THE SECTION OF PIPELINE WAS SHUTDOWN UTILIZING LINE STOPPER EQUIPMENT AT 12:30 ON JANUARY 17,2020. THE SECTION OF PIPELINE WHERE THE LEAK WAS PINPOINTED WAS REPLACED VIA HORIZONTAL DIRECTION BORE. AFTER REPAIRS AND ONCE THE DAMAGE WAS PHYSICALLY EXPOSED, IGC DISCOVERED A SMALL SECTION OF COAL TAR WRAP HAD BEEN KNOCKED OFF AND RE-WRAPPED WITH A FIELD APPLIED COATING. BASED ON THE VINTAGE OF FIELD WRAP, THE ORIGINAL COATING DAMAGE OCCURRED PRIOR TO 1993. THERE IS NO EVIDENCE OF DAMAGE (I.E. DENT, SCRATCH OR WALL LOSS) TO THE PIPELINE. THE OXIDATION (CORROSION) OCCURRED DUE TO A POOR APPLICATION OF THE FIELD WRAP. ON JANUARY 31, 2020, THE TO DATE REPAIR COST WAS $45,000. IGC WILL INCUR A MINIMUM OF $5,000 IN ADDITIONAL COSTS THIS SPRING WHEN THE TEMPORARY ASPHALT IS REPLACED WITH PERMANENT ASPHALT, AT WHICH TIME THE TOTAL REPAIR COSTS WILL EXCEED $50,000. THE NRC REPORT NUMBER OF THE 48-HOUR CONFIRMATION CALL IS 1270070. 6/29/2020 - CORRECTED PART A - 7 FROM EST TO MST. UPDATED PART D - 2B. TO INCLUDE PERMANENT ASPHALT REPAIR COSTS.