California utility regulators toughened their stance toward Pacific Gas & Electric Co. on Friday, one week after a gas pipeline explosion and fire killed at least four people and destroyed or damaged dozens of homes in the San Francisco suburb of San Bruno.
The executive director of the California Public Utilities Commission wrote PG&E President Christopher Johns asking for detailed information about potential weak links in the utility's 5,700-mile natural gas transmission network.
Foremost among the PUC's seven demands is a request for PG&E's list of its top 100 high-priority pipeline projects. The San Francisco-based, for-profit company repeatedly refers to the list in documents filed with the PUC but has not provided the commission or journalists with the actual document.
PUC Executive Director Paul Clanon asked for all versions of the list compiled since 2007 along with the status of individual replacement projects, maps showing pipe segment locations and detailed descriptions of PG&E's criteria for ranking the riskiness of various pipeline segments.
In addition to asking for a breakdown of replacement priorities on the PG&E system, the PUC is ordering the company "to describe and provide justification for how long it will take" to develop a list of locations where manual shut-off valves might be replaced with automatic or remotely controlled shut-off valves. Such devices can be closed in less than 10 minutes, experts say. It took PG&E workers more than two hours to close the manual valves on either side of the San Bruno rupture, leaving gas in the line that fed an out-of-control fire.