NORTHERN NATURAL GAS CO — Gas transmission and gathering — incident on 2003-04-01

Gas transmission and gathering incident in LORRRAINE, RICE County, KS. Reported cause: 21. Reported consequences: 0 fatalities, 1 injuries, $1,557,000 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: 20030045.

Operator ID: 13750.

Reported incident date: 4/1/2003.

Cause detail: THREADS STRIPPED, BROKEN PIPE COUPLING

Cause detail: A THREADED ONE-INCH PIPE NIPPLE IN A COMPRESSOR UNIT DISCHARGE PULSATION BOTTLE DRAIN BROKE, PROBABLY DUE TO HIGH CYCLE FATIGUE. NATURAL GAS WAS IGNITED BY UNKNOWN SOURCE. GAS FIRE CAUSED A LUBRICATING OIL FILTER ON ADJACENT COMPRESSOR UNIT TO LEAK RESULTING IN A LUBRICATING OIL FIRE. NATURAL GAS FIRE WAS VERY SHORT DURATION DUE TO RAPID SHUT IN AND VENTING OF GAS BY STATION ESD SYSTEM. 3-30-04 DURING REPAIRS NORTHERN TOOK ADVANTAGE OF THE OPPORTUNITY TO REPLACE AND UPGRADE THE FIRE AND GAS DETECTION SYSTEMS. THREE UNITS WERE REPAIRED AND RETURNED TO SERVICE AND ONE UNIT WAS NOT RETURNED TO SERVICE. ALL OF THE MODIFICATIONS AND REPAIRS COST ABOUT $3.2 MILLION. THERE IS ALSO AN ON-GOING INITIATIVE TO LOCATE OTHER SMALL DIAMETER PIPING THAT MIGHT BE SUBJECT TO VIBRATION AND CYCLIC FATIGUE.

PHMSA trend classification: significant incident, serious incident.

PHMSA standardized cause: EQUIPMENT FAILURE — THREADED CONNECTION/COUPLING FAILURE.

PHMSA indexed costs: $1,557,000 reported total cost, $994,501.216 in 1984 dollars, $2,401,624.755 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.