CONSUMERS ENERGY CO

Incident Narrative

ON APRIL 20, 2020 AT APPROXIMATELY 10:05 HOURS, CONSUMERS ENERGY WAS NOTIFIED BY THEIR CONTRACTOR PERFORMING LEAK SURVEY OF A POTENTIAL LEAK ON LINE 1014. LINE 1014 IS A 16"" HIGH PRESSURE CW STEEL PIPELINE INSTALLED IN 1968 AND LOCATE IN WATERFORD, MICHIGAN (OAKLAND COUNTY). A GAS SERVICE WORKER (GSW) WAS DISPATCHED AND ARRIVED ON-SITE AT APPROXIMATELY 10:28 HOURS. THE GSW CONFIRMED THE PRESENCE OF A LEAK AND REQUESTED A GAS DISTRIBUTION CREW BE DISPATCHED TO THE LOCATION. AN INVESTIGATION DETERMINED THE LEAK SOURCE AS A 16"" VALVE (VALVE HA-15). THE VALVE WAS INJECTED WITH GREASED IN AN ATTEMPTED TO SEAL THE LEAK ON APRIL 20, 2020 AND APRIL 21, 2020. THE AREA WAS ALSO AERATED TO ELIMINATE ANY RESIDUAL GAS TRAPPED IN THE SOIL. THE SITE WAS MONITOR OVERNIGHT. ON APRIL 21, 2020 AT APPROXIMATELY 18:25 HOURS THE PIPELINE PRESSURE WAS LOWERED FROM 259 PSIG TO 207 PSIG IN PREPARATION FOR THE SITE TO BE EXCAVATED AND THE VALVE FACILITY ASSESSED TO CONFIRM THE GAS RELEASE WAS SECURE. THE CREW CONTINUED THEIR INVESTIGATION AND AS A SAFETY PRECAUTION, PERSONNEL REMAINED ON SITE. ON APRIL 22, 2020 THE LOCATION WAS EXCAVATED AND THE SOURCE OF THE LEAK WAS DETERMINED TO BE AT THE FLANGE. THE LEAK WAS CLASSIFIED AND PLANS TO RETURN TO THE SITE THE FOLLOWING DAY TO TIGHTEN AND/OR REPLACE THE BOLTS. ON APRIL 23, 2020 IT WAS DETERMINE THE ATTEMPT TO TIGHTEN BOLTS TO RESOLVE THE LEAK WAS UNSUCCESSFUL AND VALVE REPLACEMENT WOULD BE REQUIRED. THE LEAK WAS EVALUATED AND RECLASSIFIED PENDING ENGINEERING REVIEW AND REPLACEMENT PLAN DEVELOPMENT. THE SITE EXCAVATION REMAINS OPEN AND HAS BEEN SECURED TO PREVENT POTENTIAL HAZARDS TO THE PUBLIC. A VALVE REPLACEMENT PLAN IS BEING DEVELOPED. IN AUGUST 2020 (AUGUST 15 - SEPTEMBER 2) THE EXISTING 16"" S-HP-20%SMYS (HA-15) VALVE WAS REMOVED AND REPLACED WITH AN 8"" S-HP (HA-69) VALVE. FOLLOWING VALVE REPLACEMENT, NORMAL OPERATION WAS RESUMED.