NV ENERGY

Incident Narrative

ON 12/27/2010 AT 0748 HRS. CITY OF RENO INFORMS NV ENERGY DISPATCH THAT A PHONE MESSAGE WAS LEFT ON 12/25/2010 REPORTING A GAS ODOR ON SOUTH MEADOWS PARKWAY BETWEEN DOUBLE R BLVD. AND DOUBLE DIAMOND PARKWAY. NV ENERGY DISPATCH CREATES WORK ORDER. AT 0953 HRS A PASSERBY REPORTS A GAS ODOR AT SOUTH MEADOWS PARKWAY AND DOUBLE R BLVD. TO NV ENERGY DISPATCH. NV ENERGY PERSONNEL ARRIVE ON SCENE AT 1100 HRS. TO BEGIN LEAK INVESTIGATION. AT 1223 HRS. NV ENERGY PERSONNEL DISCOVER A GRADE 1 GAS LEAK AND REQUEST ADDITIONAL PERSONNEL FOR PINPOINTING AND REPAIRS. AREA IS MADE SAFE BY NV ENERGY PERSONNEL AND NO EVACUATIONS ARE REQUIRED. LEAK IS DETERMINED TO BE ORIGINATING FROM A 2' VALVE FACING NORTH. NV ENERGY BEGINS AERATING THE SOIL DUE TO UNDERGROUND GAS MIGRATION. TRAFFIC CONTROL AND LOCATES ARE REQUESTED. REPAIRS ARE STARTED AT 1500 HRS. GAS LEAK IS STOPPED AT 1910 HRS. REPAIRS ARE COMPLETED AT 2040 HRS. NV ENERGY CONTINUES AERATING SOIL 24 HOURS PER DAY FROM 12/27/2010 TO 1/8/2011 AT 830 HRS. SOIL AERATION COSTS PUSH THE INCIDENT COSTS ABOVE THE $50,000 THRESHOLD. BASED ON A LETTER FROM KEROTEST, THE VALVE MANUFACTURER, DATED JULY 17, 2002, NV ENERGY BELIEVES THE FAILURE OF THE VALVE BONNET BOLTS IS DUE TO STRESS CORROSION CRACKING. THE AFFECTED YEARS OF MANUFACTURE ARE 1986-1996 AS IDENTIFIED BY KEROTEST. A POSSIBLE CONTRIBUTING FACTOR WAS A LACK OF COATING ON THE BONNET BOLT. ATTACHMENT: KEROTEST LETTER DATED JULY 17, 2002