ENABLE OKLAHOMA INTRASTATE TRANSMISSION, LLC

Incident Narrative

MCALESTER LINE 263 RUPTURED JUST SOUTH OF KIOWA IN A PASTURE CAUSING A GRASS/TIMBER FIRE. LOCAL FIRE DEPARTMENT AND LOCAL AUTHORITIES ARRIVED ON SCENE TO ASSIST. NO INJURIES AND NO STRUCTURES WERE INVOLVED. THE PIPELINE FIRE DISSIPATED FROM SHUTTING THE GAS IN AND FIRE DEPARTMENT WAS ABLE TO CONTROL FIRE AND KEEP IT FROM SPREADING. THE DAMAGED SECTION OF PIPE WAS REMOVED AND SHOWED SIGNS OF THIRD-PARTY DAMAGE. IT HAS BEEN SENT TO A METALLURGIST FOR FURTHER ANALYSIS AND WE ARE AWAITING THE RESULTS. NOTE: THE DAMAGED SECTION OF PIPE WAS REPLACED. A GAUGE PIG WAS RAN ON 8/22/13 BEFORE PIPELINE WAS PLACED BACK INTO SERVICE. SUPPLEMENTAL INFORMATION. THE METALLURGIST REPORT CONCLUDED THAT THE THIRD PARTY DAMAGE RESULTED IN: FRACTURE INITIATED ON A DAMAGED AREA OF THE PIPELINE WHERE DEEP GOUGE MARKS WERE NOTED ON THE OUTSIDE SURFACE. THERE WERE TWO PARALLEL SCRAPE MARKS RUNNING ROUGHLY IN THE LONGITUDINAL DIRECTION AND PRODUCED CONSIDERABLE DEFORMATION OF THE STEEL. FINAL FAILURE OF THE PIPELINE WAS A RESULT OF DUCTILE OVERLOAD. EXTERNAL DAMAGE AND NECKING HAD RESULTED IN A WALL THICKNESS REDUCED TO APPROXIMATELY 0.160"" FROM THE MEASURED 0.225"" UNDAMAGED WALL NEARBY. THE UNDAMAGED SECTION OF PIPE WAS TESTED AND MET ALL THE REQUIREMENTS OF API SPECIFICATION 5L, PSL 2, GRADE X52.