TENNESSEE GAS PIPELINE COMPANY — Gas transmission and gathering — incident on 2017-01-07

Gas transmission and gathering incident in NUNELLY, HICKMAN County, TN. Reported cause: NATURAL FORCE DAMAGE. Reported consequences: 0 fatalities, 0 injuries, 7456 NATURAL GAS released, $300 reported property damage. Operator-reported incident data submitted to PHMSA, generally within 30 days. Records may be supplemented or corrected and do not represent final agency causal findings.

Report number: 20170013.

Operator ID: 19160.

Reported incident date: 1/7/2017 15:43.

Location detail: MP 559

Cause detail: TEMPERATURE

Cause detail: ON JANUARY 7, 2017 AT 3:43 PM TGP CENTERVILLE STATION 860 EXPERIENCED AN ESD DUE TO ACTIVATION OF A UVIR DETECTOR IN "A" COMPRESSOR BUILDING WHEN A SMALL AMOUNT OF GLYCOL LEAKING ON THE SPARK PLUG PORTS IGNITED BRIEFLY. ON-SITE PERSONNEL DETERMINED THAT A BLOCK-VALVE FAILED TO CLOSE UPON ACTIVATION OF THE ESD. THEY SHUT-IN THE BLOWDOWN VALVES TO STOP THE RELEASE AND BEGAN INVESTIGATING TO DETERMINE WHY THE BLOCK-VALVE DID NOT CLOSE. THE INVESTIGATION FOUND THAT DISTILLATE HAD FROZEN IN THE OPERATOR CONTROL-LINE FOR VALVE ABS5002R. THIS PREVENTED THE VALVE OPERATOR FROM PROPERLY ACTUATING TO SHUT THE VALVE RESULTING IN A TOTAL UNINTENTIONAL GAS LOSS OF 7,456 MCF TO ATMOSPHERE. FOLLOWING THE EVENT, PERSONNEL VERIFIED THAT ALL ESD SYSTEM-VALVES OPERATED PROPERLY AND THE CONTROL LINES ARE CLEAR OF LIQUIDS. GOING FORWARD THE STATION WINTERIZATION PLAN WILL INCLUDE A PROCESS TO ENSURE LIQUIDS ARE REMOVED FROM CONTROL LINES.

PHMSA trend classification: not significant, not serious.

PHMSA standardized cause: NATURAL FORCE DAMAGE — TEMPERATURE.

PHMSA indexed costs: $25,650 reported total cost, $24,216.958 in 1984 dollars, $29,915.829 in current-year dollars.

PHMSA trend flags, standardized causes, and indexed costs are analytical fields added to operator-reported incident data. They do not represent final agency causal findings.