PHMSA Report 20180114 - SOUTHERN NATURAL GAS CO — Gas transmission and gathering — incident on 2018-10-18 | Regulus

Gas transmission and gathering incident in Not Within a Municipality, ST. MARTIN County, LA. Reported cause: EXCAVATION DAMAGE. Reported consequences: 0 fatalities, 0 injuries, 474 NATURAL GAS released, $2,000,000 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: 20180114.

Operator ID: 18516.

Reported incident date: 10/18/2018 10:15.

Location detail: 17 - 02+08

Cause detail: EXCAVATION DAMAGE BY OPERATOR'S CONTRACTOR (SECOND PARTY)

Cause detail: EXCAVATION ISSUE

Cause detail: EXCAVATOR FAILED TO MAINTAIN CLEARANCE AFTER VERIFYING MARKS

Cause detail: BECAUSE OF PIPELINE DEPTH AND DEVELOPING SITE CONDITIONS, A PREVIOUSLY PLANNED ANOMALY REPAIR PROJECT HAD BEEN HALTED WITH THE DECISION TO RETURN THE PIPELINE TO SERVICE UNTIL NECESSARY PROJECT DETAILS AND ADDITIONAL PLANS WERE ESTABLISHED TO PROPERLY CONTINUE THE ANOMALY REPAIR PROJECT. OCTOBER 18, 2018, OPERATIONS HAD BEGUN FLOWING NATURAL GAS INTO THE VACATED VALVE SECTION. TWENTY MINUTES INTO THE RE-PRESSURE PROCESS, SNG OPERATIONS AND SNG ANOMALY REPAIR CONTRACT EMPLOYEES NOTICED BUBBLES APPEARING IN JAKE'S BAYOU. VALVES WERE IMMEDIATELY CLOSED; RELEASE OF NATURAL GAS WAS AN EIGHT MINUTE DURATION. PRESSURE OF THE NATURAL GAS IN THE VALVE SECTION WAS 26 PSIG. WITH THE VALVE SECTION AT ZERO PRESSURE, OCTOBER 31, 2018, THE SNG CONTRACTOR SUCCESSFULLY RECOVERED THE PIPE CONTAINING EXCAVATION DAMAGE. FOLLOWING THE NECESSARY PERMITTING PROCESS AND THE BEGINNING OF LOW WATER SEASON IN THE BAYOU, THIRD QUARTER 2019, SNG'S CONTRACTOR BEGAN THE PIPELINE REPAIR PROCESS IN JAKE'S BAYOU. DECEMBER 04, 2019, SNG RETURNED THE REPAIRED PORTION OF THE SOUTH SECTION 28 LINE TO SERVICE.

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: EXCAVATION DAMAGE — OPERATOR/CONTRACTOR EXCAVATION DAMAGE.

PHMSA indexed costs: $2,255,328 reported total cost, $1,079,228.45 in 1984 dollars, $2,653,047.506 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.