CHEVRON PIPE LINE CO

Incident Narrative

17:55 CONTROLLER ON DUTY RECEIVES SUMP OVERFLOW ALARM AT AVON PUMP STATION WHICH TRIPS AND LOCKED OUT P2. ADJUSTMENTS ARE MADE TO KEEP RICHMOND BOOSTER PUMP ONLINE TO KEEP A MFL INSPECTION TOOL MOVING. 17:57 CONTROLLER CALLS OPERATOR AT BETHANY STATION THAT IS RECEIVING THE MFL INSPECTION TOOL THAT THE AVON PUMP IS DOWN 18:10 OPERATOR CALLS CONTROLLER WHEN ARRIVING AT AVON PUMP STATION. SUMP IS PLACED FROM AUTO INTO LOCAL TO BRING DOWN SUMP LEVELS 18:45 CONTROLLER NOTIFIES OP REP TO INFORM HIM AVON PUMP IS DOWN AND FLOW RATES/PRESSURES ARE BEING MONITORED 19:48 CONTROLLER SPOKE WITH OPERATOR ON SITE AT AVON PUMP STATION WHO STATED THAT THE SUMP LEVEL IS DECREASING AT A SLOWER RATE THAN EXPECTED 20:57 OPERATOR CALLS CONTROLLER NOTIFYING THAT A SECOND EMPLOYEE IS AT AVON PUMP STATION TO ASSIST WITH THE SUMP PUMP 22:44 OPERATOR IDENTIFIES THAT THE SUMP PUMP AT AVON PUMP STATION IS DECREASING AT A SLOWER RATE BECAUSE OF A THERMAL PRESSURE RELIEF VALVE ON THE SUCTION HEADER OF THE PUMP PREMATURELY OPENING, CAUSING THE SUMP TO FILL SUMP TO OVERFLOW. PRV WAS ISOLATED FOR REPAIRS. 00:25 OPERATOR CALLED CONTROL AND SAID HE WAS GOING TO TEST SHUTDOWN SWITCH ON OVERFLOW P2 WENT DOWN IMMEDIATELY.