6. Discussion

Pursuant to Public Utilities Code Section 451 each public utility in California must:

Furnish and maintain such adequate, efficient, just and reasonable service, instrumentalities, equipment and facilities,...as are necessary to promote the safety, health, comfort, and convenience of its patrons, employees, and the public.

The duty to furnish and maintain safe equipment and facilities falls squarely on California public utilities, including PG&E. The burden of proving that particular facilities are safe also rests with PG&E.

The Executive Director and this Commission have taken extraordinary steps to restrict the operating pressure on certain of PG&E's natural gas transmission pipelines in response to the worst tragedy in California history from public utility operations. PG&E's voluntary restrictions on Lines 101, 132A, and 147 are consistent with Commission's safety objectives. In D.11-09-006, the Commission set forth the specific requirements for PG&E to demonstrate that the operating pressure restrictions can safely be removed and we will use these requirements to evaluate PG&E's proposed pressure increases. These requirements begin with a pressure test complying with regulations applicable when conducted, and also require a responsible engineer's review of the pipeline construction and assessment of the pressure test results to ensure safe operations. The end result is that PG&E must be fully accountable for the pressure test and the assertion that the line can be safety operated at the increased maximum operating pressure.

PG&E began its validation process for Lines 101, 132A, and 147, with associated shorts, by creating a pipeline features list showing each component of the pipeline facilities. PG&E based its pipeline features list on design plans, as-built drawings, purchase orders, pressure test records, coating information, as well as other available documents. PG&E then reviewed the pipeline features list to establish the maximum pressure for each feature.

PG&E conducted pressure tests and submitted data for these tests as well as those performed for facilities when they were originally installed for review by CPSD. PG&E also provided supporting documentation for 10 excavations of pipeline which it conducted to obtain or validate specifications of pipeline facilities such as seam type, yield strength, diameters and wall thicknesses.

CPSD has examined PG&E's supporting information and found that PG&E's activities were consistent with proper maximum allowable operating pressure validation. CPSD also reviewed PG&E's procedures related to pressure testing of pipeline facilities. Although unable to review and confirm each detail of PG&E's voluminous data set, CPSD was able to confirm that all transmission level facilities have been subject to pressure testing in accord with federal regulations found at 49 CFR Part 192, subpart J, or the regulations in effect at the time the test was performed.1

PG&E has presented adequate supporting documents including pipeline features lists and pressure test results supporting its assertion that Lines 101, 132A, 147, and associated shorts, can be safely operated with a maximum operating pressure of 365 psig.

PG&E's Vice President of Gas Transmission, Maintenance, and Construction, testified under oath that PG&E's engineers have validated the engineering and construction through records review, as documented in the exhibits to the supporting information. PG&E's Vice President testified that for all transmission pipeline segments and components on Line 101, 132A, and 147 operating at or above 20% specified minimum yield strength, PG&E has either located prior pressure test records, administered in accordance with the applicable standards at the time, or successfully pressured tested in accord with 49 CFR Part 192 , subpart J at pressure above that necessary to confirm the safe operation of Lines 101, 132A, and 147 at a maximum operating pressure of 365 psig, with an additional margin of safety.

PG&E's Vice President concluded that in his professional judgment, Lines 101, 132A, and 147 are safe to operate at 365 psig.

We, therefore, find that PG&E's responsible engineer has reviewed the engineering and construction of the segments, as well as the results of the pressure tests, and concluded that the maximum operating pressure may be safely increased to 365 psig.

PG&E operates a natural gas transmission and distribution system. As the operator, PG&E must ensure that the system is operated safely. PG&E presented pressure test results, supporting information, and the testimony of its responsible engineer verifying that the maximum operating pressure of Lines 101, 132A, and 147 can be safely increased to 365 psig.

Therefore, we conclude that PG&E has demonstrated that the maximum operating pressure of Lines 101, 132A, and 147 can be safely increased to 365 psig.

1 CPSD also recommended that PG&E either pressure test or replace Line 101 short, GCUST7013, and PG&E testified that this short will be replaced and pressure tested prior to December 15, 2011. (November 22, 2011 Hearing Transcript at 658.)

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