The CPUC simultaneously denied a request by the utility to submit such requests solely to the commission's executive director and outside the public hearing process.

Following the Sept. 9, 2010 explosion on a PG&E transmission pipeline that killed eight people in San Bruno, the CPUC ordered the utility to reduce by 20 percent the maximum allowable operating pressure on all of its pipelines with characteristics similar to Line 132.

Those characteristics included pipelines that ran through densely populated areas, those that were 30 inches in diameter with seam welds similar to Line 132, and those that were installed before 1962 that had never undergone hydrostatic pressure testing.

PG&E complied with the order, and in a motion filed with the CPUC in July, the utility asked the commission to delegate sole authority to CPUC executive director Paul Clanon to approve requests to restore operating pressure on the lines where pressure had been reduced.

In its motion, PG&E proposed sending Clanon a letter specifying the segments where pressure was to be restored, and asked that Clanon respond to the request within 10 business days, according to the CPUC.

The utility cited the need for an expedited process to avoid "unnecessary delays" or "adverse customer impacts."

The city of San Bruno was among the parties who objected to PG&E's proposal and recommended that any process to restore operating pressure should be analyzed by independent experts and reviewed by the commission at a public hearing.

The CPUC today denied PG&E's motion and established a public process for the utility to submit requests to raise operating pressure on its pipelines.

The utility will be required to bring forward a senior engineer to present pressure test data and other information at a public CPUC hearing in order to restore operating pressure.

"PG&E must be fully accountable for the pressure test and the assertion that the line can be safely returned to a higher maximum operating pressure," commissioner Mike Florio said in a statement.