COLORADO INTERSTATE GAS CO — Gas transmission and gathering — incident on 2011-12-10

Gas transmission and gathering incident in NEAREST TOWN IS HYRUM, CACHE County, UT. Reported cause: NATURAL FORCE DAMAGE. Reported consequences: 0 fatalities, 0 injuries, 1000 NATURAL GAS released, $1,622,000 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: 20120005.

Operator ID: 2564.

Reported incident date: 12/10/2011 18:40.

Location detail: 73 + 1205

Cause detail: EARTH MOVEMENT, NOT DUE TO HEAVY RAINS/FLOODS

Cause detail: COLORADO INTERSTATE GAS (CIG) COMPANY GAS CONTROL EMPLOYEES NOTICED A PRESSURE DIFFERENTIAL ON THE 42" RUBY PIPELINE DURING THE EARLY EVENING OF DECEMBER 10, 2011. FIELD OPERATIONS EMPLOYEES WERE DISPATCHED TO MLV 6 AND FOUND A FIRE IN PROGRESS AT THE VALVE SITE. THE AFFECTED SEGMENT WAS ISOLATED AND BLOWN DOWN IN ORDER TO EXTINGUISH THE FIRE. THE ENSUING INVESTIGATION DETERMINED THAT THE LIKELY CAUSE OF THE INCIDENT WAS EARTH SETTLEMENT STRESSING A 1-INCH POWER GAS LINE WHICH BROKE, RELEASED GAS, AND IGNITED. THE SOURCE OF THE IGNITION IS BELIEVED TO BE THE ONSITE THERMOELECTRIC GENERATOR (TEG). PREVAILING WIND IS BELIEVED TO HAVE CARRIED THE RELEASED GAS TOWARD THE TEG, WHERE IT IGNITED, WITH SECONDARY FIRES SPREADING TO OTHER EQUIPMENT AT THE SITE. THE PIPELINE HAS BEEN REPAIRED AND PLACED BACK INTO SERVICE. PLEASE NOTE THAT FORM WOULD NOT ACCEPT THE DIGITS REQUIRED FOR THE ACTUAL VOLUME OF GAS IN PART A, QUESTION 11. THE ACTUAL VOLUME IS 181,055 MCF OR 181.055 MMCF.

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: NATURAL FORCE DAMAGE — EARTH MOVEMENT.

PHMSA indexed costs: $2,278,500 reported total cost, $1,322,304.06 in 1984 dollars, $2,730,977.634 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.