PHMSA Report 20180063
PHMSA Report 20180063
Gas transmission and gathering incident in Not Within a Municipality, MATAGORDA COUNTY County, TX. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 13911 NATURAL GAS released, $1,200 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: 20180063.
Operator ID: 4900.
Reported incident date: 5/28/2018 10:02.
Location detail: STATION 3B
Cause detail: MALFUNCTION OF CONTROL/RELIEF EQUIPMENT
Cause detail: ON 5/28/18 TEJAS GAS PIPELINE (TEJAS) GAS CONTROL RECEIVED A CALL FROM A LOCAL NEARBY RESIDENT AT APPROXIMATELY 10:30 AM LOCAL TIME WITH A REPORT OF GAS VENTING AT THE 3B COMPRESSOR STATION IN MATAGORDA COUNTY, TEXAS. AT APPROXIMATELY 10:35 AM LOCAL TIME, GAS CONTROL DISPATCHED TEJAS OPERATIONS PERSONNEL TO INVESTIGATE THE REPORT OF VENTING GAS. AT 11:12 AM LOCAL TIME, OPERATIONS PERSONNEL CONFIRMED, ISOLATED, AND STOPPED THE RELEASE OF NATURAL GAS. THEY DETERMINED THE GAS ORIGINATED FROM THE RELIEVE VALVE (PSV 2020) ON COMPRESSOR UNIT NO. 1. A TOTAL OF 13,911 MSCF OF NATURAL WAS RELEASED AND REPORTED TO THE NRC AND THE TEXAS RAILROAD COMMISSION. A COURTESY NOTIFICATION TO THE PHMSA ACCIDENT INVESTIGATION GROUP WAS ALSO PROVIDED. A REVISED NRC REPORT WAS SUBMITTED TO CORRECT THE COMPANY NAME AND LOCATION INFORMATION (NRC NO. 1213482) ON THE SAME DAY OF THE EVENT AND A 48-HOUR UPDATE WAS ALSO PROVIDED (NRC NO. 1213568) THE FOLLOWING DAY. PSV 2020 IS LOCATED ON 10' DIAMETER STATION DISCHARGE PIPING BETWEEN THE COMPRESSOR ENGINE AND THE COOLING FANS. UPON INVESTIGATION, IT WAS DETERMINED THE RELEASE OF GAS WAS CAUSED BY THE PSV 2020 ACTUATING BELOW ITS ESTABLISHED SET-POINT. THE PRESSURES OBSERVED DURING THE EVENT DID NOT EXCEED THE ESTABLISHED MAOP OF THE STATION OR DOWNSTREAM FACILITIES. A REVIEW OF OPERATION AND MAINTENANCE RECORDS FOR PSV 2020 SHOWED IT WAS LAST TESTED ON 3/26/18 AND REPORTED TO BE WORKING PROPERLY WITH NO PROBLEMS NOTED. THE EVENT WAS CLASSIFIED AS AN ABNORMAL OPERATION AND THE IMMEDIATE CAUSE OF THE RELEASE WAS IDENTIFIED AS DEFECTIVE EQUIPMENT: A DEFECTIVE O-RING IN THE PILOT VALVE HOUSING CAUSED THE PILOT VALVE TO OPEN THE RELIEF VALVE PRIOR TO THE ESTABLISHED SET POINT. THE ROOT CAUSE OF THE O-RING FAILURE WAS DETERMINED TO BE EXCESSIVE WEAR AND TEAR. THE EXISTING PILOT UNIT WAS REMOVED AND REPLACED WITH A NEW PILOT AND PSV 2020 WAS PLACED BACK INTO SERVICE ON 5/29/18.
PHMSA trend classification: not significant, not serious.
PHMSA standardized cause: EQUIPMENT FAILURE — MALFUNCTION OF CONTROL/RELIEF EQUIPMENT.
PHMSA indexed costs: $36,089 reported total cost, $33,098.056 in 1984 dollars, $41,418.015 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.
This material provides agency context. It does not replace binding regulatory text, and its legal effect depends on the underlying authority and facts.