ENABLE GAS TRANSMISSION, LLC

Incident Narrative

ON APRIL 27TH, SYSTEM CONTROL CALLED OUT PERSONNEL TO INVESTIGATE HIGH GAS PRESSURE ALARMS RECEIVED FROM THE LINE JM-30 METERING FACILITY AT GRAVEL RIDGE, AR. GAS FLOW RATE WAS ALSO OBSERVED TO INCREASE FROM LINE J INTO LINE JM-30. SYSTEM CONTROL RECEIVED REPORTS FROM LOCAL EMERGENCY PERSONNEL THAT GAS WAS BLOWING NEAR FOXGROVE AND BOBBIT LANES IN GRAVEL RIDGE AND RESIDENTS WERE BEING EVACUATED. NEIGHBORHOOD ROADS WERE BEING CLOSED. SYSTEM CONTROL ALSO RECEIVED CALLS FROM LOCAL OPERATING PERSONNEL REPORTING TORNADO ACTIVITY NEAR MAYFLOWER, ARKANSAS. AT THE JM-30 VILONIA INTERCONNECT FACILITY, COMPANY PERSONNEL FOUND SEVERE DAMAGE TO CONTROL VALVES, METERS AND ESPECIALLY TO INSTRUMENT TUBING FROM FLYING DEBRIS CAUSED BY A TORNADO. THE INSTRUMENT / RTU BUILDING WAS DEMOLISHED. LARGE PORTIONS OF THE FACILITY FENCE WERE MISSING. ELECTRIC POWER SERVICE WAS INTERRUPTED. THE DAMAGE TO THE AREA WAS SO WIDESPREAD THAT INITIALLY OPERATIONS PERSONNEL HAD TO WALK INTO THE SITE DUE TO DEBRIS. THE DAMAGE TO THE VILONIA INTERCONNECT FACILITY DISABLED THE PRESSURE REGULATION AND CONTROL FOR THE SOUTHERN SEGMENT OF JM-30. JM-30 LINE PRESSURE HAD INCREASED AT THE END OF LINE JM-30 AT GRAVEL RIDGE UNTIL THE RELIEF VALVE OPENED TO PREVENT OVER PRESSURING OF THE METERS. NO DIRECT TORNADO DAMAGE WAS OBSERVED AT THE GRAVEL RIDGE FACILITY. HOWEVER, THE ESCAPING GAS AND WINDY CONDITIONS PROMPTED THE GRAVEL RIDGE FIRE DEPARTMENT TO MAKE EVACUATIONS AS A PRUDENT PRECAUTION TO THE SITUATION. LOCAL OPERATING PERSONNEL ARRIVED AT THE INLET TO JM-30 FROM LINE J AND WERE INSTRUCTED TO CLOSE LINE J VALVE J-6 TO REDUCE PRESSURE INTO JM-30 AND TO STOP THE RELIEVING OF GAS AT GRAVEL RIDGE. AFTER THE LINE PRESSURE DECREASED AND THE RELIEF VALVE HAD BEEN RESET, THE AREA AT GRAVEL RIDGE WAS CHECKED AND FOUND TO BE CLEAR OF GAS. THE EVACUATED GRAVEL RIDGE RESIDENTS WERE ALLOWED TO RETURN HOME AT 10:20 PM. IT WAS ESTIMATED THAT AS MANY AS 500 PEOPLE HAD BEEN EVACUATED FROM ALMOST 170 HOMES. ROADS WERE OPENED FOR TRAFFIC. OPERATIONS AND SYSTEM CONTROL PERSONNEL DEVISED A PLAN TO RESUME JM-30 OPERATIONS.