WASHINGTON GAS LIGHT CO

Incident Narrative

WASHINGTON GAS WAS TOLD BY THE FIRE DEPARTMENT THAT THE METER VALVE WAS TURNED OFF BY THEM AT APPROXIMATELY 22:00. UPON GAINING ACCESS TO THE METER ON DECEMBER 20TH, WASHINGTON GAS CONDUCTED A PRESSURE TEST ON THE SERVICE LINE FROM THE METER VALVE TO THE CAPPED OFF LOCATION AT THE MAIN. THE SERVICE WAS TESTED AT THE OPERATING PRESSURE FOR 15 MINUTES. THE SERVICE LINE HELD THE PRESSURE TEST. AN ODORANT SAMPLE WAS TAKEN AND THE LEVEL OF ODORANT WAS DETERMINED TO BE ACCEPTABLE. WASHINGTON GAS HAS CONDUCTED ALL THE NECESSARY TESTS AND ACTIVITIES ON THE SYSTEM. ALTHOUGH POST INCIDENT INVESTIGATION FOUND CORROSION AT THE CONNECTION AT THE SERVICE TEE, ON THE STEEL MAIN, NEITHER WASHINGTON GAS NOR THE FIRE DEPARTMENT INVESTIGATION ESTABLISHED MIGRATION OF GAS FROM THE WASHINGTON GAS FACILITY TO THE STRUCTURE PRIOR TO THE INCIDENT. ADDITIONALLY, AN OPEN-ENDED SECTION OF THE CUSTOMER FUEL LINE TERMINATING ON THE SECOND FLOOR WAS FOUND. AS THE INTERIOR FUEL LINE OPERATED AT APPROXIMATELY .25 PSIG, GAS WOULD BE ESCAPING FROM THIS OPENING AT THAT PRESSURE UNTIL THE SERVICE REGULATOR CEASED TO FUNCTION PROPERLY AS A RESULT OF THE DAMAGE FROM THIS INCIDENT. THE ROOT CAUSE OF THIS INCIDENT REMAINS UNDETERMINED; THEREFORE, THE ANSWERS TO QUESTIONS NUMBERS 14 & 15 REMAIN ""NO"". WHILE THE FAIRFAX COUNTY FIRE DEPARTMENT MAY HAVE CONCLUDED, ON DECEMBER 31, 2010, THAT NATURAL GAS CONTRIBUTED TO THE INCIDENT, IT HAS YET TO BE DETERMINED WHO OR WHAT WAS AT FAULT. BASED UPON ALL KNOWN INFORMATION, THE CAUSE IS UNDETERMINED.