SUNOCO, INC (R&M)

Incident Narrative

4/23/2010 NARRATIVE DESCRIPTION (PARTIAL): ON 3/25/2010 AT 13:45 HOURS, A CONTRACTOR EMPLOYEE WORKING FOR SUNOCO, INC. (R&M) ENTERED THE WEST YARD SECTION OF THE PHILADELPHIA REFINERY AND DISCOVERED A RELEASE OF HEAVY OIL AROUND A VALVE MANIFOLD WHICH CONNECTS THE FM-1 PIPELINE TO THE N-8 PIPELINE. THE CONTRACTOR EMPLOYEE NOTIFIED SUNOCO PERSONNEL AND A RESPONSE WAS INITIATED. THE VACUUM GAS OIL (VGO) TRANSFER WAS SHUTDOWN AT 14:00 HOURS AND, DUE TO THE HIGH VISCOSITY OF THE PRODUCT, THE HEAVY MATERIAL WAS IMMEDIATELY DISPLACED FROM THE PIPELINE WITH LIGHT CYCLE OIL (LCO) AND ISOLATED BY 18:00 HOURS. ON 4/5/2010, THE SOURCE OF THE RELEASE WAS DETERMINED TO HAVE BEEN A FLANGED CONNECTION ON THE FM-1 PIG TRAP, NORMALLY ISOLATED, EXCEPT DURING PIGGING ACTIVITY. THE PIG TRAP WAS LAST USED DURING AN IN-LINE INSPECTION CONDUCTED ON JUNE 23, 2008. A MORE THOROUGH EVALUATION WILL BE PERFORMED TO IDENTIFY THE FAILURE MECHANISM THAT RESULTED IN THE RELEASE FROM THE FLANGED CONNECTION. A HYDROCHEM (VACUUM TRUCK) EMPLOYEE, WHO ROUTINELY MONITORED AND MANAGED RESIDUAL OIL THAT ACCUMULATED IN REFINERY SUMPS, INCLUDING THE WEST YARD VALVE MANIFOLD VAULT, REPORTED THAT OIL ACCUMULATION APPEARED TO INTENSIFY AND WAS FOUND OUTSIDE THE VAULT BEGINNING ABOUT 3/15/2010. THIS WAS BELIEVED TO BE CAUSED BY TYPICAL RESIDUAL GROUND SEEPAGE EXACERBATED BY EXCESSIVE RAINFALL AND SNOW THAW. OPERATIONS TURNOVER REPORTS FROM 3/15/10 TO 3/25/10 HAVE ONLY ONE REPORT OF HEAVY OIL ON WATER (3/18/10). THIS AGAIN WAS REMOVED BY HYDROCHEM VACUUM TRUCKS. ON THE MORNING OF 3/16/2010 , TWO SUNOCO EMPLOYEES WERE IN THE WEST YARD FOR TRAINING PURPOSES AND DID NOT NOTICE A LEAK OR HEAVY OIL AT THAT TIME. ON 3/24/2010 AT 11:00 HOURS, ANOTHER SUNOCO EMPLOYEE WAS IN THE WEST YARD AND DID NOT REPORT A RELEASE AT THAT TIME. IN ADDITION, ON 3/24 AT 13:37 HOURS, A HYDROCHEM EMPLOYEE ENTERED THE WEST YARD TO VACUUM RESIDUAL OIL FROM THE VALVE MANIFOLD VAULT. THE RELEASE IS BELIEVED TO HAVE STARTED IN THE 24 HOURS PRIOR TO DISCOVERY. A TOTAL OF 1,700 BARRELS WAS RELEASED AND NEARLY ALL OF THE MATERIAL HAS BEEN RECOVERED. 5/19/2010 UPDATE: THE FM-1 PIG TRAP WAS ABOUT 39 1/2' IN LENGTH, MEASURED FROM THE FLANGE AT THE INLET/OUTLET VALVE TO THE FLANGE AT THE CLOSURE. THE TRAP WAS INITIALLY SUPPORTED AT THREE LOCATIONS. THE TRAP WAS SUPPORTED AT THE CONTAINMENT WALL AROUND THE MANIFOLD, 9'-4' FROM THE FLANGE AT THE CLOSURE. THE TRAP WAS ALSO SUPPORTED BY ITS FLANGED CONNECTION TO THE INLET/OUTLET VALVE. DUE TO ITS LENGTH, IT WAS ALSO SUPPORTED, ADJACENT TO THE FAILED CENTER FLANGE. THE CENTER FLANGE WAS 5'-0' FROM THE INLET/OUTLET VALVE. THE CENTER SUPPORT IS BELIEVED TO HAVE BEEN LOCATED IN THE 5' SPOOL, WITHIN 12' FROM THE CENTER FLANGE. THE SUPPORT CONSISTED OF A STRUCTURAL COLUMN, A BASE PLATE AT THE BOTTOM THAT RESTED ON THE FLOOR OF THE MANIFOLD CONTAINMENT, AND A TWO-PART CLAMP-STYLE FITTING AT THE TOP WHICH SECURED THE SUPPORT TO THE OUTSIDE DIAMETER OF THE CARRIER PIPE. ONCE THE FM-1 TRAP WAS REMOVED, THE CENTER SUPPORT WAS FOUND IN THE CONTAINMENT, DETACHED AND SEPARATED FROM THE FM-1 TRAP PIPING. IT IS CONCLUDED THAT THE LACK OF SUPPORT AT THE CENTER FLANGE, ALLOWED PIPE MOVEMENT OVER TIME, INCLUDING MOVEMENT CAUSED BY THERMAL CYCLING, WHICH APPLIED A DIFFERENTIAL STRESS ON THE FLANGE BOLTS AND EVENTUALLY CAUSED THE FLANGE TO OPEN AT THE 8:00 O'CLOCK POSITION. THE FM-1 TRAP INLET/OUTLET VALVE WAS FOUND TO HAVE A MECHANICAL DEFECT WHICH PREVENTED A TIGHT SHUT-OFF, WHICH ALLOWED PRODUCT FROM THE FM-1 PIPELINE TRANSFER TO PASS THROUGH THE VALVE, INTO THE PIG TRAP, CAUSING THE RELEASE FROM THE CENTER FLANGE. NO CORROSION OF THE FLANGE FACES OR OTHER MECHANICAL DAMAGE WAS OBSERVED.