MICHIGAN CONSOLIDATED GAS CO (MICHCON)

Incident Narrative

AT 15:30 ON AUGUST 16, 2010 MICHCON RECEIVED A REPORT OF LEAKING GAS ON MELLON STREET WEST OF DIX ROAD IN THE CITY OF DETROIT, WAYNE COUNTY, MI. MICHCON REPAIR CREWS CONDUCTED LEAK POLICY CHECKS AND DETERMINED THE LEAK WAS ON THE 24"" 150 PSIG TRANSMISSION PIPELINE (FORT STREET 150 PSIG SYSTEM). ENGINEERING DETERMINED THAT THE PRESSURE MUST BE REDUCED TO 45 PSIG PRIOR TO EXCAVATING OF THE 24"" PIPELINE. AT 17:30 REPAIR CREWS REPORTED THAT A 24"" VESSEL (DRIP POT) WAS LEAKING BELOW THE 24"" PIPELINE AND WOULD BE UNABLE TO MAKE PERMANENT REPAIRS. ON AUGUST 17, 2010, ENGINEERING DETERMINED THAT A 24"" STOPPLE FITTING AND VALVE SHUTDOWN WOULD BE REQUIRED TO ELIMINATED THE LEAK. ON SEPTEMBER 2, 2010 THE 24"" STOPPLE FITTING WAS INSTALLED. AT 14:00 ON SEPTEMBER 3, 2010 THE PIPELINE WAS VALVED OFF AT THE RIVER ROUGE GATE STATION (APPROXIMATELY 1 MILE AWAY). AT 15:00 THE PIPELINE WAS BLOWN DOWN AND CLEARED. AT 21:00 A 24"" VALVE WITH A PUP AND CAP WERE INSTALLED AND THE PIPELINE WAS PHYSICALLY SEPARATED ELIMINATING THE LEAK. MICHCON PERSONNEL MONITORED THE LEAK LOCATION ONCE PER SHIFT UNTIL THE LEAK WAS ELIMINATED ON SEPTEMBER 3, 2010. AS OF 9/15, ENGINEERING IS COMPLETING PLANS TO REMOVE AND REPLACE A 185 FOOT SECTION OF PIPELINE. MICHCON INSTALLED 60' OF 24"" PIPE TO COMPLETE THE LEAK REPAIR. AN ADDITIONAL 162' OF 24"" PIPE WAS INSTALLED TO PREPARE THE PIPELINE FOR FUTURE IN-LINE INSPECTION. THE PIPELINE WAS PUT BACK IN OPERATION ON OCTOBER 8, 2010.