CYPRESS GAS PIPELINE COMPANY — Gas transmission and gathering — incident on 2017-10-28

Gas transmission and gathering incident in BATON ROUGE, WEST BATON ROUGE County, LA. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 4000 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: 20170111.

Operator ID: 12696.

Reported incident date: 10/28/2017 2:00.

Location detail: 81

Cause detail: MALFUNCTION OF CONTROL/RELIEF EQUIPMENT

Cause detail: AT 0200 PIPELINE CONTROL CENTER NOTICED A DROP IN PRESSURE ON BRW 1 PIPELINE NEAR THE BATON ROUGE GAS PLANT. PIPELINE CONTROL DISPATCHED A TECHNICIAN TO INVESTIGATE. TECHNICIAN ARRIVED ON SITE AT APPROXIMATELY 0310 AND FOUND A RELIEF VALVE RELIEVING TO ATMOSPHERE, VERIFIED PIPELINE PRESSURE WAS NOT EXCEEDING MAOP, AND CLOSED THE BLOCK VALVE UNDER THE RELIEF VALVE TO SECURE SITE. PIPELINE CONTROL CONTINUED MONITORING PIPELINE PRESSURE UNTIL A CERTIFIED TECHNICIAN ARRIVED TO MAKE REPAIRS. THE TECHNICIAN REPLACED THE PILOT ON THE RELIEF VALVE, SET NEW PILOT TO ESTABLISHED SETTING AND RETURNED THE SEGMENT TO NORMAL SERVICE. AT 0409 IT WAS DETERMINED THE VOLUME OF GAS RELEASED BY THE RELIEF VALVE EXCEEDED 3 MMSCF AND THE NRC WAS NOTIFIED AT 0419. VISUAL EXAMINATION OF THE RELIEF VALVE INDICATED FLUID BUILD-UP ON THE PILOT CAUSED IT TO RELIEF BELOW THE SET POINT. 48 HR. NRC NUMBER 1194628 INVESTIGATION OF THE RELIEF VALVE PILOT BY A THIRD PARTY VENDOR INDICATED THAT FLUID WAS PRESENT AND A FAILED O-RING SEAL WAS FOUND. THESE FACTORS CONTRIBUTED TO THE RELIEF VALVE LIFTING BELOW THE SET POINT. THE REPLACEMENT PILOT HAS BEEN OPERATING AS INTENDED FROM TIME OF INSTALLATION WITH NO ISSUES.

PHMSA trend classification: not significant, not serious.

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

PHMSA indexed costs: $11,600 reported total cost, $10,738.002 in 1984 dollars, $13,546.802 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.