MICHIGAN CONSOLIDATED GAS CO (MICHCON)

Incident Narrative

ON OCTOBER 4, 2011, A GAS LEAK REPAIR ORDER FOR THE ADDRESS OF 456 MORAN IN GROSSE POINTE FARMS, WAYNE COUNTY, MI WAS ASSIGNED TO A TWO PERSON CREW. THE CREW CONSISTED OF A DISTRIBUTION GENERAL FITTER AND A SERVICE TECHNICIAN. THE CREW EXCAVATED AND EXPOSED A 6-INCH CAST IRON DISTRIBUTION MAIN OPERATING AT 5 PSIG. THE DISTRIBUTION GENERAL FITTER, WHILE WEARING A SUPPLIED AIR-RESPIRATOR, PREPARED THE CAST IRON MAIN FOR INSTALLATION OF A 6-INCH BY 9-INCHES IN LENGTH PIPE REPAIR CLAMP. THE DISTRIBUTION GENERAL FITTER INSTALLED THE CLAMP AND TIGHTENED THE BOLTS TO STOP THE LEAK. THE DISTRIBUTION GENERAL FITTER REMOVED THE SUPPLIED AIR-RESPIRATOR FOR UNKNOWN REASONS. THEREAFTER, HE PROCEEDED TO FINISH TIGHTENING THE BOLTS AND SOAP CHECK THE PIPE TO VERIFY THAT THE LEAK WAS STOPPED. AT THAT TIME, THE SERVICE TECHNICIAN LEFT THE TOP OF THE EXCAVATION AND WENT TO THE TRUCK TO RETRIEVE COATING FOR THE REPAIR CLAMP WHEN HE HEARD THE SOUND OF GAS BLOWING FROM THE EXCAVATION. THE SERVICE TECHNICIAN IMMEDIATELY RETURNED TO THE EXCAVATION AND FOUND THE DISTRIBUTION GENERAL FITTER KNEELING FACE DOWN OVER THE GAS MAIN AND UNRESPONSIVE TO VERBAL COMMANDS. THE SERVICE TECHNICIAN ATTEMPTED TO RETRIEVE THE DISTRIBUTION GENERAL FITTER FROM THE EXCAVATION BUT WAS UNABLE TO DO SO AND CALLED 911. GROSSE POINTE FARMS POLICE AND EMS PERSONNEL RESPONDED TO THE SCENE AND PULLED THE DISTRIBUTION GENERAL FITTER FROM THE EXCAVATION; HE WAS TRANSFERRED TO ST. JOHN'S HOSPITAL IN DETROIT, MI WHERE HE WAS PRONOUNCED DEAD. A SECOND REPAIR CREW WAS CALLED IN TO REPAIR THE GAS MAIN FOLLOWING THE INCIDENT AND INSTALLED A 6-INCH BY 12-INCHES IN LENGTH REPAIR CLAMP ADJACENT TO THE FIRST REPAIR CLAMP; HOWEVER THE CLAMP FURTHER CRUSHED THE CORRODED/WEAKENED PIPE. BOTH REPAIR CLAMPS WERE REMOVED AND A 6-INCH BY 30-INCHES IN LENGTH REPAIR CLAMP WAS INSTALLED TO REPAIR THE LEAK. ON NOVEMBER 1, 2011, THE PIPE WAS REMOVED AND RECOVERED FOR EXAMINATION AND A METALLURGICAL ANALYSIS BY A THIRD PARTY LABORATORY. THE ANALYSIS CONCLUDED THAT LOCALIZED GRAPHITIC CORROSION WEAKENED THE FRACTURED PIECES OF PIPE THAT WERE CRUSHED WHEN TIGHTENING THE REPAIR CLAMPS.