When in Mountain View this May, it will pump 175,000 gallons of water through it.
This type of information, and a lot more technical stuff, was made available to Mountain View residents who attended the first of two town hall meetings sponsored by the utility company Monday night at . Nearly 25 people stopped in throughout the evening.
The second town hall will be Tuesday night at the school between 5:30-8:30 p.m.
"We are here to educate customers about what's going on," said PG&E's Brittany Chord. "This is part of our extensive community outreach. We want them to be informed."
A stretch of 1.45 miles of pipeline, primarily beneath the neighborhood of Rex Manor, will be emptied of all its natural gas and filled with water pressurized upward of 150 percent greater than normal to determine the reliability of the segments, PG&E spokespeople explained.
Company engineer G. Mitchell Kirk explained that on normal days, the pipelines in Mountain View and around the Bay Area pump gas at a federal maximum allowable operating pressure (MAOP) of 50 percent of pipeline capacity. Ever since a California Public Utilities Commission pipeline 132 explosion last year, pipelines operate 20 percent below the MAOP, he clarified.
That's why the hydrostatic test will pump water at a greater pressure, Kirk added.
According to PG&E, there will be only surface excavation at the beginning of the line near Sierra Vista Avenue and at the Shoreline Golf Links. After the excavation, the gas will be vented, which could cause residents to smell some gas but won't cause interruption to service.
Water, stored in containers on the golf course, will be pumped in, and an electronic device will measure any changes in pressure for an eight-hour period. If pressure decreases, it would signify that a leak existed, and then the utility would replace the pipe along that segment. The replacement pipe would meet pressure tests.
Chord confirmed that this type of hydrostatic testings "is the industry standard," that "it's common practice" and that "nothing out of the ordinary" should happen.
The Mountain View residents who dropped by the town hall also hoped they had nothing to worry about.
Two friends—who both live on the same street in the Monta Loma neighborhood, on the other side of Rengstorff–asked questions and left with a lot of literature to read. Another woman, who lives on Sierra Vista Avenue next to the beginning of Line 132a, was less concerned about the hydrostatic testing than about pipeline safety in case of an earthquake. She said she didn't feel satisfied with the answers she got.
But one man, who spent a long time asking a lot of questions, said he felt better after he learned his gas wouldn't be interrupted. He said he was glad he went to the meeting.
PG&E prioritized the pipelines to be tested based on similarities to Line 132, which exploded when it ruptured on Sept. 9, 2010, killing eight people in San Bruno. The similarities include that the pipeline is beneath densely populated or "high consequence areas," and may either be missing or have inconsistent pressure test documentation based on the type of pipe.
For more information from PG&E, call 888-743-7431 or, in Spanish, 800-660-6789. For a video of what the testing entails, click here.