WOLVERINE PIPELINE CO

Incident Narrative

WOLVERINE PIPE LINE COMPANY (WPLCO) DAMAGE PREVENTION SPECIALIST (DPS), WHILE PERFORMING A STATION WALK-AROUND, DISCOVERED A LEAK ON VALVE #34 A LITTLE BEFORE 6:30 AM (CST) CONFINED TO THE PROPERTY OF OUR JOLIET PUMP STATION. AS SOON AS HE DISCOVERED THE LEAK HE CALLED THE OPERATIONS CONTROL CENTER (OCC) AND HAD THEM SHUT DOWN THE JO-KA 18"" PIPELINE AND REDUCE PRESSURE TO AS LOW AS POSSIBLE. AT THE TIME OF THE DISCOVERY THE DPS NOTICED A STEADY DRIP OF GASOLINE COMING FROM THE 1"" BODY DRAIN VALVE. HAMMOND CREW WENT TO THE SITE AND DETERMINED THE EXTENT OF THE IMPACTED AREA BY DIGGING UP THE STONE/SOIL AND DRUMMING IT UP. CLEANUP CONDUCTED THE SAME DAY, VALVE REPLACED AND RETURNED TO SERVICE. THE SAFETY HEALTH & ENVIRONMENTAL DEPARTMENT DETERMINED VOLUME TO BE 14.5 GALLONS BASED ON RELEASE DIMENSIONS. FIRST LOOK AT THE 1"" BALON VALVE SHOWED THE LEAK AT THE SPLIT OF THE BODY ON THE VALVE AS THIS IS A TWO-PIECE VALVE. VALVE HAS BEEN SENT TO THE MANUFACTURER TO DETERMINE CAUSE OF FAILURE. THE DEFECTIVE VALVE WAS SENT TO BALON CORPORATION FOR TESTING AND ANALYSIS. THE VALVE LEAKED AT THE ADAPTER ON TEST. THE BODY O-RING WAS DAMAGED, AND THE SEATS AND THRUST WASHER WERE EXTRUDED. THE VALVE WAS SUBJECT TO FAILURE FROM A THERMAL OVER PRESSURE EVENT. THE THERMAL EXPANSION OCCURRED DOWNSTREAM OF THE BALL, BETWEEN THE BALL AND A CAP THAT HAD BEEN INSTALLED ON THE VALVE. THIS PARTICULAR BALON VALVE HAS A PRESSURE RATING OF 3000 PSI, WHICH COULD ONLY HAVE BEEN EXCEEDED BY TRAPPED THERMAL PRESSURE WITHIN THE FITTING ITSELF. MAINLINE SCADA PRESSURE DATA CONFIRMS THAT THERE WERE NO OVER PRESSURE EVENTS AT THE LEAK LOCATION. A BALON ENGINEER CONCLUDED POSSIBLE ""OVER PRESSURE OTHER THAN FREEZING."" THIS IS MOST LIKELY THE RESULT OF AN INADVERTENT OPENING OF THE VALVE, FOLLOWED BY A CLOSING OF THE VALVE, WHICH WOULD HAVE TRAPPED LIQUID DOWNSTREAM OF THE VALVE BETWEEN THE CAP AND BALL. AS A RESULT OF THIS EVENT WOLVERINE PIPE LINE COMPANY IS IMPLEMENTING SOLUTIONS TO PREVENT THIS TYPE OF INCIDENT FROM HAPPENING AT OTHER SIMILARLY CONFIGURED VALVE SITES.