PG&E Statement Regarding CPUC Order December 16, 2010 ("Safety Response to the National Transportation Safety Board Advisory of December 14, 2010")
Release Date: December 16, 2010
Contact: PG&E External Communications (415) 973-5930
SAN FRANCISCO, CA-The National Transportation Safety Board this week ruled out several possible causes of the San Bruno gas pipeline rupture and explosion, but stressed that the investigation is still in an early phase and a great deal of work remains before a cause can be determined.
Nevertheless, the report did note a variance in some of the pipe welds near where the rupture occurred. As a precautionary measure, the California Public Utilities Commission today asked PG&E to lower pressure on pipelines that are similar in vintage and size to the one that ruptured in September and that have not been hydrostatically pressure tested.
Two gas transmission pipelines in PG&E's system meet the CPUC’s criteria: Line 153, which runs from Oakland to Fremont, and Line 131, from Fremont to Milpitas.
Kirk Johnson, PG&E Vice President, Gas Engineering & Operations, explained:
Safety is our number one priority. As part of our commitment to reassuring our customers, PG&E has been examining other pipelines of similar size and vintage to the segments in San Bruno to determine whether pressure could be reduced without impacting our customers. Based on that analysis, we reduced pressure on Line 153 last week to 90 percent late Friday, December 10th. Further analysis shows that we can comply with the CPUC's directive to reduce pressure on Lines 131 and 153 to 80 percent while continuing to reliably serve our customers. We will begin taking steps to reduce pressure immediately.