COLONIAL PIPELINE CO

Incident Narrative

ON JULY 16TH AT 0600, A CONTRACTOR ARRIVED AT TANK 845 TO BEGIN PREPARING THE SITE TO PULL THE TANK ISOLATION VALVE AND TAKE TANK 845 OUT OF SERVICE FOR AN API 653 INSPECTION. THE CONTRACTOR NOTICED PRODUCT STAINING AROUND THE TANK RING AND ON ADJACENT GRASSY AREAS. TANK 845 HAD BEEN EMPTIED OF GASOLINE IN PREPARATION FOR THE OOS INSPECTION AND FLUSHED (PARTIALLY FILLED AND THEN FULLY EMPTIED) WITH OIL TO DE-GAS THE TANK. INTERNAL NOTIFICATIONS WERE MADE TO THE PROJECT MANAGER, PROJECT LEADER, ASSOCIATE OPERATIONS MANAGER, OPERATIONS MANAGER AND DISTRICT DIRECTOR OF OPERATIONS. A CONTRACTOR CREW, INCLUDING A CRANE, WAS ALREADY ON SITE TO TAKE THE TANK OUT OF SERVICE AND IMMEDIATELY BEGAN WORK TO REMOVE THE TANK ISOLATION VALVE AND FLANGE OFF THE TANK LINE. A VAC TRUCK WAS ON SITE AS WELL FOR THE SAME PURPOSE AND IMMEDIATELY HELPED WITH THE CLEAN-UP PROCESS. COLONIAL CONTRACTORS AND INSPECTORS WERE ALSO ONSITE TO HELP FACILITATE THE CLEAN-UP EFFORT. A COLONIAL ENVIRONMENTAL SPECIALIST ARRIVED ON SITE AND DETERMINED THE AMOUNT WAS GREATER THAN 25 GALLONS. A NOTIFICATION WAS SUBSEQUENTLY MADE TO THE STATE. THERE WAS NO THROUGHPUT IMPACT AS THIS TANK WAS IN THE PROCESS OF BEING TAKEN OUT OF SERVICE AND WAS ISOLATED FROM THE SYSTEM SHORTLY AFTER THE RELEASE WAS IDENTIFIED. THE SOURCE OF THE LEAK WAS DETERMINED TO BE A CRACK IN THE WELD OF THE TANK FLOOR NEAR THE SUMP. APPROXIMATELY 150 GALLONS OF DIESEL FUEL HAS BEEN RECOVERED. AN ESTIMATED 100 GALLONS REMAIN IN SOILS UNDER THE TANK FLOOR. THE TOTAL RELEASE ESTIMATE AT THIS TIME IS 250 GALLONS. THE TANK REMAINS OUT OF SERVICE AND IS BEING CLEANED IN PREPARATION OF A FLOOR REPLACEMENT. ADDITIONAL ASSESSMENT AND REMEDIATION ACTIVITIES HAVE BEEN COMPLETED. THE TANK FLOOR, TANK SUMP, AND TANK LINE WERE REMOVED AND AN ESTIMATED 383 TONS OF SOILS WERE EXCAVATED AND ADDED TO THE 30 TON STOCKPILE OF SOIL PREVIOUSLY EXCAVATED OUTSITE THE TANK. LABORATORY ANALYSIS INDICATE THAT 43 GALLONS OF PRODUCT WERE CONTAINED IN THE EXCAVATED SOIL. BASED UPON RECENT SOIL SAMPLING RESULTS, AN ESTIMATED 585 TONS OF SOIL WITH LOW-LEVEL CONCENTRATIONS OF TPH REMAIN UNDER THE TANK FLOOR. AN ESTIMATED 33 GALLONS OF UNRECOVERED PRODUCT ARE CONTAINED WITHIN THESE SOILS. THE TOTAL VOLUME RELEASED IS ESTIMATED AT 280 GALLONS. 204 GALLONS OF FREE PRODUCT HAVE BEEN COLLECTED AND APPROXIMATELY 43 GALLONS WERE CONTAINED WITHIN THE 412 TONS OF IMPACTED SOIL THAT WAS REMOVED. AN ESTIMATED 33 GALLONS REMAIN WITHIN UNEXCAVATED SOILS UNDER THE TANK FLOOR. MONITORING OF WELLS ADJACENT TO THE TANK INDICATE THAT GROUNDWATER WAS NOT IMPACTED BY THE RELEASE. NO FURTHER REMEDIATION OR ASSESSMENT ACTIVITIES ARE ANTICIPATED AS A RESULT OF THIS RELEASE.