TENNESSEE GAS PIPELINE CO (EL PASO) — Gas transmission and gathering — incident on 2011-02-10

Gas transmission and gathering incident in HANOVERTON, COLUMBIANA County, OH. Reported cause: MATERIAL FAILURE OF PIPE OR WELD. Reported consequences: 0 fatalities, 0 injuries, 62374 NATURAL GAS released, $2,500,000 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: 20110026.

Operator ID: 19160.

Reported incident date: 2/10/2011 22:30.

Location detail: 214-4 + 60677

Cause detail: DESIGN-, CONSTRUCTION-, INSTALLATION-, OR FABRICATION-RELATED

Cause detail: GAS CONTROL PERSONNEL FOR TENNESSEE GAS PIPELINE (TGP) NOTICED PRESSURE DROPS RELATIVE TO ITS PIPELINE IN VALVE SECTION 214 DOWNSTREAM OF CARROLLTON COMPRESSOR STATION AND NEAR THE TOWN OF HANOVERTON, OH AROUND 10:30 PM EST ON FEBRUARY 10, 2011. SHORTLY THEREAFTER, TGP RECEIVED A REPORT FROM A LOCAL LANDOWNER OF A FIRE SOME 11,000 FEET NORTH OF VALVE 214 IN LINE 4. UPON RESPONDING, FIELD PERSONNEL VERIFIED THAT A RUPTURE HAD OCCURRED IN LINE 4 WHERE IT CROSSES MCKAIG ROAD IN COLUMBIANA COUNTY, OH. THERE WAS NO FORMAL EVACUATION OF LOCAL RESIDENTS ALTHOUGH EMERGENCY REPONDERS DID ADVISE SOME TO LEAVE THEIR HOMES AS A PRECAUTIONARY MEASURE (TGP WAS NOT INVOLVED IN ANY EVACUATION). POST-INCIDENT ROOT CAUSE ANALYSIS REVEALED THE FAILURE OCCURRED AS A RESULT OF TENSILE OVERLOAD ON A PRE-EXISTING HYDROGEN ASSISTED CRACK IN THE UNDERBEAD OF THE GIRTH WELD. THE CRACK ORIGINATED DURING THE WELDING PROCESS AT THE TIME OF ORIGINAL CONSTRUCTION. THE TENSILE OVERLOAD WAS THE RESULT OF A NUMBER OF INTERACTING STRESSORS INCLUDING BUT NOT LIMITED TO THERMAL CONTRACTION STRESSES. THE PIPELINE HAS BEEN REPAIRED, PURGED, AND LOADED WITH NATURAL GAS TO A PRESSURE OF 491 PSIG.

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: MATERIAL FAILURE OF PIPE OR WELD — CONSTRUCTION, INSTALLATION OR FABRICATION-RELATED.

PHMSA indexed costs: $2,881,072 reported total cost, $1,599,983.311 in 1984 dollars, $3,653,437.318 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.