The California Public Utilities Commission has opened a penalty proceeding to consider whether Pacific Gas & Electric violated state or federal rules related to proper classification of its natural gas transmission pipelines.
The utility submitted a class-location study report to the commission in June, as part of the follow-up to the 2010 explosion of a PG&E transmission pipe in a San Bruno residential neighborhood that killed eight people and destroyed 38 homes.
The utility's class-location review found that some segments of its system had, or may have, a maximum allowable operating pressure higher than permitted under law. The utility subsequently lowered pressure on those lines.
The PUC noted that statutory fines and penalties could reach $20,000/day for continuing violations.
PG&E spokesman David Eisenhauer said Friday that the company is giving the issue "the attention it deserves. We have already undertaken a top to bottom review to make sure our pipelines are operating at the pressures they are supposed to be."
The commission noted that in the June report, PG&E said it found 172.1 miles of pipe that were identified as being in areas of lower population density than was actually the case.
"Because PG&E has admitted that its class designations are in error for at least some of its transmission pipeline segments, PG&E appears to have failed to comply with federal regulations concerning the protection of persons and property in areas with higher concentrations of human occupancy and activity," the PUC added in its order instituting investigation.
The utility is already under investigation by the PUC in a penalty proceeding regarding its record-keeping, related to a finding by federal investigators that PG&E's records for the San Bruno pipe were inaccurate.
PG&E operates some 6,438 miles of transmission pipeline, with about 1,059 miles in high-consequence, urban areas.
