PALO ALTO (KCBS) – A small leak has been detected in Palo Alto on the same natural gas pipeline that exploded with deadly consequences last year in San Bruno, officials with Pacific Gas and Electric Company said Friday.
A hydrostatic pressure test carried out Thursday on a 4-mile section of Line 132 near Palo Alto picked up a slow and steady decrease in pressure that indicates a leak around 1 millimeter in diameter, said PG&E spokesman David Eisenhauer.
“The situation is safe. That pipe has been isolated,” he said.
KCBS’ Anna Duckworth Reports:
The pipeline was taken out of service in order to conduct the test, and Eisenhauer said it would remain sealed off from the rest of the system while crews pinpointed the location of the leak and carried out repairs.
“We isolate it with valves on either end. We remove all the natural gas out of it, re-route the natural gas through another pipe system,” he said.
It could take several days to find the leak, since the pipe must be emptied entirely before a tracer gas can be introduced that crews will try to detect by walking the length of excavated pipe.
Eisenauer said PG&E had been testing this section of 24-inch diameter seamless pipe, installed in 1947, on a weekly basis using other leak detection methods that did not find any problems.
Eisenhauer said this is the first leak found in the Bay Area since the increased pipeline testing after the San Bruno explosion in 2010. Hydrostatic tests last month revealed a seam rupture on a section of pipeline west of Bakersfield.
Because hydrostatic testing is more rigorous than other forms of leak detection, Eisenhauer said it was difficult to determine, at least initially, when the Palo Alto leak may have started.
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