NORTHERN NATURAL GAS CO — Gas transmission and gathering — incident on 2014-09-22

Gas transmission and gathering incident in SHEFFIELD, FRANKLIN County, IA. Reported cause: EXCAVATION DAMAGE. Reported consequences: 0 fatalities, 0 injuries, 407 NATURAL GAS released, $32,544 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: 20140104.

Operator ID: 13750.

Reported incident date: 9/22/2014 15:00.

Location detail: 2.5

Cause detail: EXCAVATION DAMAGE BY THIRD PARTY

Cause detail: NOTIFICATION ISSUE

Cause detail: NO NOTIFICATION MADE TO THE ONE-CALL CENTER/811

Cause detail: ON SEPTEMBER 22, 2014 AT APPROXIMATELY 15:56 NORTHERN'S OPERATIONS COMMUNICATION CENTER RECEIVED A CALL FROM FRANKLIN COUNTY EMERGENCY RESPONSE CENTER THAT THERE WAS BLOWING GAS FROM THE SHEFFIELD 4-INCH (IAB54101) BRANCH LINE. PROPERTY OWNER ROY PLAGGE HAD BEEN INSTALLING AGRICULTURAL DRAINAGE TILE IN AN UNHARVESTED CORN FIELD. PLAGGE IMMEDIATELY CALLED 911 AFTER THE BLOWING GAS WAS DETECTED. PLAGGE DID NOT HAVE A ONE-CALL TICKET AND NO UNDERGROUND UTILITIES WERE MARKED. THE TILING MACHINE PUNCTURED THE 4-INCH CREATING A HOLE ABOUT 2 INCHES LONG BY 1 INCH WIDE. THE PLOW TOOTH STUCK IN THE PIPE PROVIDED SOME LEAK STOPPAGE EFFECTS. THIS ALLOWED NORTHERN TO PROCEED SLOWLY AND DELIBERATELY WITH THE REPAIRS WITHOUT THE THREAT OF LOSING SERVICE. NORTHERN REPLACED 29 FEET OF 4-INCH PIPE AT THE PUNCTURE SITE. THE REPLACEMENT PIPE WAS PRETESTED 4-INCH, 0.250-INCH WALL THICKNESS PIPE. NORTHERN ALSO FOUND ANOTHER SPOT ABOUT 80 FEET DOWNSTREAM WHERE THE TILING MACHINE HAD CAUSED A GREATER THAN 6% DENT WITH METAL LOSS. TWENTY FIVE FEET OF PIPE WAS INSTALLED AT THIS LOCATION. MR PLAGGE HAS RECEIVED MAILINGS AND BROCHURES FROM NORTHERN'S PUBLIC AWARENESS PROGRAM FOR SEVERAL YEARS. HE IS AWARE OF THE ONE CALL SYTEM AND EVEN USED IT IN THE PAST ON THIS PROPERTY. NO CUSTOMERS LOST NATURAL GAS SERVICE DURING THE REPAIRS. EVEN FARM TAP CUSTOMERS NEVER LOST SERVICE THANKS TO NORTHERN'S VOLUME BOTTLE TRAILERS AND WARMER WEATHER.

PHMSA trend classification: significant incident, not serious.

PHMSA standardized cause: EXCAVATION DAMAGE — THIRD PARTY EXCAVATION DAMAGE.

PHMSA indexed costs: $101,477 reported total cost, $51,958.228 in 1984 dollars, $125,793.369 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.