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CPUC Pipeline Safety Frequently Asked Questions Oct. 8, 2010 - page 4 / 6





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    Welding and Joining procedures

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    Drug and Alcohol testing

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    Public Awareness Program (going forward as the Pipeline and Hazardous Materials

Safety Administration creates inspection process for this)

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    Integrity Management Program

Q: What types of inspections were done on the San Bruno segment of pipe in March and in November 2009? A: PG&E performed aerial pipeline patrols of Line 132 from approximately 16 miles south of the rupture location to the San Francisco county line on the following dates (03/18/09; 06/29/09; 09/16/09; 12/09/09; 03/17/10; and 06/16/10). None of these patrols noted any dead vegetation, construction, or other activity occurring near the incident location.

Leak surveys performed by PG&E, which included the rupture location on Line 132, were performed on the following dates: May 23-25, 2008; March 25, 2009; and March 18, 2010.

Finally, in 2009, PG&E performed a Direct Assessment on Line 132 as part of the baseline assessment of the line required by federal pipeline safety regulations. As noted above, the External Corrosion Direct Assessment process has four steps. Step 1 – pre-assessment includes data collection, and feasibility assessment to select the appropriate indirect assessment tool to use. Step 2 of the ECDA process includes indirect inspections. Indirect assessment was performed on a segment of Line 132 (M.P. 37.80-43.75), which included the location involved in the September 9th explosion and fire. The particulars of this indirect assessment will be examined as part of the NTSB’s investigation. The type of indirect assessment method generally utilized by PG&E for this segment is a Close-Interval Survey. A close-interval survey involves a person holding electrodes walking along the line or close to the line to measure the current to ensure that the cathodic protection is working all along the line. The purpose of the survey is to identify areas where the cathodic protection may not be working effectively. This survey method detects situations such as pipeline coating holidays, interference, and contact with other metallic structures that may interfere with cathodic protection. Based on the indications received in the Step 2 survey, Step 3 calls for Direct Examinations of specific locations. Direct examination requires excavation of the pipe to measure coating defects, metal loss. Step 3 may also include ultrasonic testing or X-ray of the pipe. PG&E performed some Phase 3 - Direct Examinations in 2009 on Line 132 (specific locations will be confirmed as part of the NTSB investigation), but no direct examination excavations included the location involved in the September 9th explosion and fire.

Q: What is the history of actions the CPUC took to enforce or implement NTSB findings? A: Following the September 12, 2008, Metrolink – Union Pacific Railroad multiple fatality collision in Chatsworth, the NTSB issued a new recommendation and reiterated previous recommendations to the Federal Railroad Administration (FRA):

  • New: Inward-facing cameras should be installed on railroad (e.g., Union Pacific RR, Burlington Northern Santa Fe, Amtrak, Metrolink) locomotives to monitor the crew’s actions. The FRA has jurisdiction regarding the installation of devices on railroad locomotives. However, the CPUC currently has a formal proceeding open to adopt an


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