COLONIAL PIPELINE CO

Incident Narrative

AT 0730 ON JANUARY 7, 2014, A SPARTANBURG AREA TECHNICIAN WAS CALLED OUT TO INVESTIGATE AN ALARM ON UNIT 3 AT SIMPSONVILLE STATION. UPON COMPLETION OF THE WORK ON UNIT 3, THE TECHNICIAN NOTICED STAINED GRAVEL AROUND A BURIED DRAIN VALVE ON THE SUCTION SIDE OF UNIT 1. SOIL WAS EXCAVATED AROUND THE DRAIN VALVE. SHEARED BOLTS WERE OBSERVED ON THE BODY OF THE VALVE WHICH CAUSED THE VALVE TO SEPARATE AND LEAK. THE STATION WAS ISOLATED AND SKILLETS WERE INSTALLED AROUND THE VALVE TO STOP THE LEAK. APPROXIMATELY 40 GALLONS OF PRODUCT WERE REMOVED FROM THE EXCAVATED AREA. THE IMPACTED SOIL WAS SET ASIDE FOR DISPOSAL. A SMALL AMOUNT OF PRODUCT ENTERED THE SUB-SURFACE DRAIN WHICH LEADS TO THE OIL/WATER SEPARATOR. ON JANUARY 8, 2014 CREWS EXCAVATED IMPACTED SOILS AROUND THE AFFECTED SUB-SURFACE DRAIN LINES. WATER WAS USED TO FLUSH 73 GALLONS OF RESIDUAL PRODUCT FROM THE DRAIN LINE INTO THE OIL/WATER SEPARATOR. PRODUCT COLLECTED FROM THE EXCAVATION AND OIL/WATER SEPARATOR WAS RETURNED TO THE SYSTEM VIA THE STATION SUMP. IMPACTS TO THE DRAIN SYSTEM AND SURFICIAL SOILS WERE ADDRESSED. FOLLOW UP INVESTIGATION ACTIVITIES WERE SCHEDULED TO CONFIRM THAT NO PRODUCT REMAINED IN THE SUBSURFACE DRAIN SYSTEM AND EVALUATE SOIL AND GROUNDWATER IMPACTS AT DEPTH BELOW THE EXCAVATION AROUND THE VALVE. ON JANUARY 10, 2014 A VAC TRUCK AND CREW BEGAN INSTALLING BORINGS IN THE AREA OF THE VALVE TO ASSESS ADDITIONAL IMPACTS AT DEPTH. TWO BORINGS BENEATH THE RELEASE AREA REVEALED FREE PRODUCT IN A SANDY LAYER OF SOIL APPROXIMATELY 11 FEET DEEP. THE VAC TRUCK INSERTED STINGER PIPES INTO THE BORINGS AND REMOVED THE FREE PRODUCT. SEVERE WEATHER WAS ANTICIPATED AND THE BORINGS WERE ALLOWED TO RECHARGE TO SEE IF PRODUCT RETURNED. THE INVESTIGATION CONTINUED WITH THE INSTALLATION OF APPROXIMATELY 25 BORINGS INSTALLED BY HAND AND VAC TRUCK THE WEEK OF JANUARY 13. NRC NOTIFICATION WAS MADE ON JANUARY 15 AT 10:53 (REPORT #1071203) WHEN ANTICIPATED COSTS EXCEEDED THE COST REPORTING $50,000 REPORTING THRESHOLD. SOUTH CAROLINA DHEC WAS NOTIFIED ON JANUARY 15 AT 11:00. PRODUCT RECOVERY OPERATIONS RAMPED UP OVER THE WEEK OF JANUARY 13 TO INCLUDE VACUUM EXTRACTION OF PRODUCT FROM 8 RECOVERY WELLS INSTALLED ACROSS THE MANIFOLD YARD AND A RECOVERY TRENCH INSTALLED JUST ADJACENT TO THE YARD. A STREAM LOCATED APPROXIMATELY 400 TO 500 FEET FROM THE MANIFOLD YARD IS BEING MONITORED ON A ROUTINE BASIS EACH DAY. NO IMPACTS TO THE STREAM HAVE BEEN IDENTIFIED. THE EXTENT OF FREE PRODUCT IN THE SUBSURFACE HAS BEEN DELINEATED AND IS CONFINED TO THE MANIFOLD AND AREA JUST DOWNGRADIENT OF THE MANIFOLD WITHIN THE STATION BOUNDARIES. SOIL IMPACTS APPEAR TO BE MINIMAL AND WERE LIMITED TO THE IMMEDIATE AREA OF THE VALVE. NO OFF SITE IMPACTS HAVE BEEN IDENTIFIED. ASSESSMENT ACTIVITIES ARE CONTINUING WITH THE INSTALLATION OF MONITORING AND RECOVERY WELLS. PRODUCT RECOVERY OPERATIONS ARE CONTINUING. 2/18/14 UPDATE: RELEASE VOLUME ESTIMATE ADJUSTED TO 52,000 GALLONS. THIS VOLUME IS BASED UPON PRELIMINARY DATA FROM WHICH AN ESTIMATED RELEASE DATE AND DURATION WERE CALCULATED. AS ADDITIONAL DATA BECOMES AVAILABLE THE RELEASE VOLUME MAY BE ADJUSTED. ENVIRONMENTAL REMEDIATION COSTS WERE ALSO ADJUSTED TO ACCOMMODATE LONGER TERM ANTICIPATED EXPENDITURES. APPROXIMATELY 34,500 GALLONS HAVE BEEN RECOVERED FROM THE GROUNDWATER REMEDIATION SYSTEM INSTALLED AT THE SITE. MONITORING OF GROUNDWATER WELLS INSTALLED AROUND THE PERIMETER OF THE FACILITY INDICATE THE RELEASED PRODUCT IS CONFINED TO THE FACILITY PROPERTY. 2/10/2015 FINAL UPDATE: THE FINAL RELEASE VOLUME ESTIMATE REMAINS AT 52,000 GALLONS. A TOTAL OF 44,000 GALLONS OF PRODUCT HAVE BEEN RECOVERED UTILIZING ORIGINAL PUMP/REMEDIATION SYSTEM. UPDATED REMEDIATION SYSTEM HAS BEEN DESIGNED AND IS SCHEDULED FOR INSTALLATION IN LATE FEBRUARY 2015. ITS INSTALLATION AND OPERATION ARE REFLECTED IN UPDATED COST ESTIMATE.