During the Live Oak City Council meeting held September 6, 2017 Management Analyst Alison Schmidt explained the August 9 power outage caused by a contractor working on the Pennington Road project. Schmidt explained she was representing City Engineer Scott Rolls who could not make the meeting.
As explained in a staff report submitted by Rolls, just before 5 p.m., on August 9, 2017, All-American Construction hit a pressurized gas main in the intersection of Pennington and Larkin Roads.
"Although the concentration of gas did not reach an explosive level, the close proximity of the leak to electrical substation triggered a precautionary action to cut power to the substation causing a power outage in the community and surrounding area until approximately 10 p.m.
"It is important for Council to be aware that the City's contractor is not at fault. The Contractor had properly delineated the project limits and requested utility facility marking through USA (Underground Service Alert, also referred to as "811") prior to any work beginning on the project. The contractor had renewed the request prior to the incident even though the existing request had not yet expired. The Contractor had coordinated with PG&E to have a PG&E inspector on the job site at all times (referred to as "standby"). The gas main that was it had not been marked by PG&E even though it was well within the USA limits delineated by the Contractor."
Rolls reviewed the remaining excavation work required to complete the project following this event with the Contractor to determine if significant risk exists for another conflict. Rolls reported that the majority of the excavation work had already been competed which lowers the risk substantially. The remaining work consists of four short (30 to 50 feet long) excavations to tie the new facilities into the existing City water system and replace fire hydrants. At two of these locations, the gas facilities have already been located and exposed during prior work which reduces the risk.
"At the other two locations, Orchard Way and Larkin Road (connecting south of Pennington) gas facilities have not been previously exposed. These locations are where the risk is more significant. To mitigate the risk, the Contractor will use a combination of vacuum excavation, probing and hand excavating/trench spotting for excavator work. To further mitigate the risk at Orchard Way, I have directed the Contractor to relocate the connection point approximately 40 feet to the west of the location shown on the plans to maintain maximum separation from the gas facilities marked in the field."
The city of Gridley also had their power cut that night and was not informed. At the time of the outage, Gridley Electric crews were on a service call to replace a bad transformer in Biggs, calling in extra crews to trouble shoot the outage in Gridley because they had not been told PG&E had cut the power.
Power in Gridley was restored in Gridley at approximately 9 p.m., and the Gridley crew was notified of the power being out on Nevada Street in Heron Landing subdivision and found a bad transformer, possibly due to the "in-rush" of current when the power was restored. The transformer was replaced and power was restored around 1:30 a.m.