NORTHERN NATURAL GAS CO

Incident Narrative

IN THE EARLY MORNING HOURS OF AUGUST 6, 2010, A LOCAL RESIDENT LOST CONTROL OF HIS VEHICLE. THE VEHICLE LEFT THE ROAD, ROLLED NUMEROUS TIMES AND FINALLY ENDED UP INSIDE THE FENCING OF THE HAWKEYE/MENLO RENEWABLES ETHANOL PLANT TOWN BORDER STATION, WHICH IS OWNED AN OPERATED BY NORTHERN NATURAL GAS COMPANY AND SUPPLIES NATURAL GAS TO THE ETHANOL PLANT. ONE INDIVIDUAL WAS DEAD AT THE SITE AND ONE WAS TRANSPORTED BY LIFE FLIGHT TO A HOSPITAL AND DIED SHORTLY THEREAFTER. THE VEHICLE STRUCK AND DAMAGED HIGH-PRESSURE NATURAL GAS PIPING IN SEVERAL PLACES IN THE TOWN BORDER STATION. A 1/4-INCH DIAMETER PIPE FITTING, BETWEEN THE STATION INLET FILTER AND THE FILTER INLET GAUGE ISOLATION VALVE WAS BROKEN, CAUSING THE RELEASE OF HIGH PRESSURE GAS. THE STATION PIPING WAS ISOLATED AND BLOWN DOWN TO ZERO PRESSURE AND UPON CLOSER OBSERVATION IT WAS DECIDED THAT THE 7.5 MILE LONG, 6-INCH BRANCH LINE TO THE STATION NEEDED TO BE ISOLATED AND BLOWN DOWN IN ORDER TO ENSURE SAFETY FOR ALL PERSONNEL WHILE INSPECTING FOR DAMAGE AND REPAIRING PIPING WITHIN THE TOWN BORDER STATION. THERE WERE NO DEFECTS FOUND BUT THE 6-INCH DIAMETER IN-LINE INSPECTION TOOL RECEIVER INLET AND THE 4-INCH DIAMETER STATION INLET VALVES WERE FOUND TO BE DAMAGED. BOTH THE 6 AND 4-INCH VALVES WERE REPLACED AS WELL AS THREE FITTINGS AND VARIOUS SMALL LENGHTS OF PIPE TO FACILITIATE REPLACEMENT OF THE VALVES. THERE WAS NO FIRE, EXPLOSION OR EVACUATIONS BECAUSE OF THE INCIDENT. UPON COMPLETION OF REPAIRS THE BRANCH LINE AND THE TOWN BORDER STATION WERE PURGED, RE-PRESSURIZED WITH NATURAL GAS AND SERVICE WAS RESTORED TO THE ETHANOL PLANT. THE VEHICLE CRASH WAS INVESTIGATED BY THE IOWA STATE HIGHWAY PATROL AND LOCAL COUNTY LAW ENFORCEMENT OFFICIALS. FINAL REPORT: THE TOTAL COST OF REPAIRS WAS REVISED TO CALCULATE THE FINAL TOTAL OF $93,372. THIS REPORT IS CONSIDERED COMPLETE WITH NO FURTHER ACTIONS PENDING. SUPPLEMENTAL/FINAL: UPDATE PART E5F WITH TRANSMISSION PER PHMSA REQUEST ON REPORT 20100052 DATED 8/31/2010. SUPPLEMENTAL/FINAL: UPDATE ON TIMELINE OF EVENTS. THE INDIVIDUALS CRASHED INTO THE TOWN BORDER STATION AROUND 01:30. LOCAL POLICE DID NOT ARRIVE AT THE STATION UNTIL 05:35 THE SAME MORNING. NORTHERN WAS NOT NOTIFIED UNTIL 06:00 AS SHOWN IN PART A4.