SOUTHERN STAR CENTRAL GAS PIPELINE, INC — Gas transmission and gathering — incident on 2012-02-08

Gas transmission and gathering incident in YUMA County, CO. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 5360 NATURAL GAS released, $0 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: 20120026.

Operator ID: 31711.

Reported incident date: 2/8/2012 5:05.

Location detail: 150/223331

Cause detail: MALFUNCTION OF CONTROL/RELIEF EQUIPMENT

Cause detail: GAS CONTROLLER RECEIVED A CALL FROM THE YUMA STATION OPERATOR AT APPROXIMATELY 0752 CST ON 08 FEB 2012 IN REGARDS TO A RELIEF VALVE BLOWING.� THE RELIEF VALVE IS LOCATED DOWNSTREAM OF THE HIGH PRESSURE FUEL GAS REGULATOR 013153R AND UPSTREAM OF THE LOW PRESSURE FUEL GAS REGULATOR 013152R.� THE STATION OPERATOR HAD NO INDICATION OF WHEN THE RELIEVE VALVE ACTIVATED.� BASED ON THE YUMA MAINLINE PRESSURE PROFILE ON SCADA, INDICATIONS WERE THERE THAT SHOWS THAT THE RELIEF VALVE PROBABLY WAS ACTIVATED APPROXIMATELY AT 0505 ON 08 FEB 2012 AND WAS SHUT-IN AT APPROXIMATELY 0812. AT 0820 CST THE OPERATOR CALLED GAS CONTROL TO INFORM THEM IT THE R.V. HAD GONE OFF DUE TO A FREEZE IN THE REGULATOR RUN. NO ALARMS WERE INDICATED AT YUMA STATION OF ANY POTENTIAL MALFUNCTION.� A CALL WAS PLACED TO THE NATIONAL RESPONSE CENTER AT 0923 CST ON 08 FEB 2012.� THE NRC CREATED TICKET 1002451 IN RESPONSE TO THIS REPORTING. YUMA STATION HAS A HEAT EXCHANGER THAT WARMS THE GAS BEFORE IT ENTERS THE FUEL RUN. THERE IS ALSO A PILOT HEATER FOR THE REGULATOR INSTALLED. DUE TO THE FACT THAT YUMA STATION WAS OFF LINE THE HEAT FROM BOTH THE HEAT EXCHANGER AND THE PILOT HEATER WERE ONLY WARMING STAGNANT GAS. THE AMBIENT TEMPERATURE AT YUMA AT THE TIME OF THIS INCIDENT WAS APPROXIMATELY 0 DEGREES F. THIS ALLOWED THE MOISTURE INSIDE THE PILOT FOR REGULATOR 13153R TO FEEZE CAUSING THE REGULATOR TO FAIL WHICH ACTIVATED THE R.V.

PHMSA trend classification: not significant, not serious.

PHMSA standardized cause: EQUIPMENT FAILURE — MALFUNCTION OF CONTROL/RELIEF EQUIPMENT.

PHMSA indexed costs: $13,453 reported total cost, $11,234.535 in 1984 dollars, $13,794.302 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.