With regulators increasing concerns about data gaps related to the pressure testing of sections of high-pressure natural gas transmission pipelines, Pacific Gas and Electric Co. (PG&E) this month has assumed a data-gathering approach, while refusing to speculate on how much of the 1,800 miles of transmission pipeline it has traversing high-consequence areas (HCA) may need testing.
Part of the regulators' concern focused on a database that PG&E maintains on all of its pipeline segments, but the review over the next two months is focused on paper records (job files) of every work order tied to particular segments. "The computerized [geographic information] system is not the total system of record [although regulators have focused on it]," a utility spokesperson told NGI last Friday. "There is a lot of historical information in the paper files that isn't included in the electronic data base. The pipelines in many cases were installed well before computers were around."
State regulatory officials have speculated that there could be segments now operating in unsafe situations similar to what could have happened with a portion of PG&E's Line 132 in San Bruno that suffered a rupture last September, killing eight people and destroying 37 homes. Nevertheless, the spokesperson said the utility is on top of the situation and will have answers by March 15 (with an interim report Feb. 1).
Whether there are risky portions of the PG&E 6,000-mile transmission pipeline system that need to be pressure tested is not known, and until it is, the utility won't speculate on the level of safety in the pipeline operations, the spokesperson said.
"Once it is determined whether testing is required, we will develop a plan," said the PG&E spokesperson, who noted that it will take a lot of work to avoid any major outages or disruptions as a result of the pressure tests.
Earlier this month after the National Transportation Safety Board (NTSB) issued urgent recommendations on the record-keeping issues, the California Public Utilities Commission (CPUC) directed PG&E and other major utility pipeline operators in the state to conduct pressure tests on any pipeline segments for which there are not accurate records of previous tests being completed (see Daily GPI, Jan . 14).
"What we do know at this point is that the [PG&E] records are incomplete," CPUC General Counsel Frank Lindh said last Thursday in response to a question from Commissioner Timothy Alan Simon. "How incomplete they are is what we will learn from this resolution by the commission. This directive will help us find all of this out."
The review is focused on the HCA areas in more densely populated places. It involves 1,800 miles of pipeline -- not the entire 6,000-mile PG&E gas transmission pipeline system, the utility spokesperson said.
The most complete records are the paper ones, so PG&E asked for and received CPUC permission to have until mid-March to finish its review and report for the regulators. In this regard, PG&E is not that different than the rest of the gas pipeline industry, the spokesperson said.
"The nation's pipeline infrastructure for the most part was developed in the pre-computer era," the spokesperson said.
"This is a substantial undertaking," said Brian Cherry, the utility vice president for regulatory affairs in a letter to the CPUC Jan. 7. "We are marshaling both internal and significant external resources, and we will deliver the results of our pressure testing verification work on March 15."
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