NATIONAL FUEL GAS SUPPLY CORP — Gas transmission and gathering — incident on 2018-11-22

Gas transmission and gathering incident in TOWN OF EVANS, ERIE County, NY. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 5300 NATURAL GAS released, $200 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: 20180134.

Operator ID: 13063.

Reported incident date: 11/22/2018 21:23.

Location detail: RELIEF VALVE

Cause detail: MALFUNCTION OF CONTROL/RELIEF EQUIPMENT

Cause detail: NATIONAL FUEL GAS SUPPLY CORPORATION HAS REPORTED A NATURAL GAS INCIDENT AS A RESULT OF AN UNINTENTIONAL RELEASE OF NATURAL GAS ESTIMATED AT GREATER THAN THREE (3) MILLION CUBIC FEET, THAT OCCURRED AT 7700 FERRIER RD. IN THE TOWN OF EVANS, ERIE COUNTY, NY. NATIONAL FUEL CONFIRMED DISCOVERY OF THE INCIDENT ON WEDNESDAY NOVEMBER 28, 2018 AFTER COMPLETING A COMPREHENSIVE FLOW ANALYSIS OF GAS LOST DURING A RELIEF VALVE RELEASE THAT OCCURRED FROM APPROXIMATELY 9:23 PM TO 11:33 PM ON THURSDAY NOVEMBER 22ND, 2018. THE PROBABLE CAUSE OF THE INCIDENT WAS EQUIPMENT FAILURE OF A RESTRICTOR VALVE FOR A RELIEF VALVE CONTROL THAT CAUSED THE DEVICE TO FAIL IN AN OPEN POSITION. THERE WERE NO INJURIES OR PROPERTY DAMAGE. THE UPDATED NRC REPORT NUMBER 1231680.

PHMSA trend classification: not significant, not serious.

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

PHMSA indexed costs: $18,300 reported total cost, $16,039.583 in 1984 dollars, $21,050.877 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.