NTSB Safety Recommendation P-11-027

NTSB safety recommendation P-11-027.

TO PACIFIC GAS AND ELECTRIC COMPANY: Expedite the installation of automatic shutoff valves and remote control valves on transmission lines in high consequence areas and in class 3 and 4 locations, and space them at intervals that consider the factors listed in Title 49 Code of Federal Regulations 192.935(c).

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 2011-09-26

Adopted Date: 2011-09-12

Overall Date Closed: 2015-12-01

Synopsis: On September 9, 2010, about 6:11 p.m. Pacific daylight time,1 a 30-inch-diameter underground natural gas transmission pipeline (which is identified by the company as Line 132), owned and operated by Pacific Gas and Electric Company (PG&E), ruptured in a residential area in San Bruno, California. The accident killed eight people, injured many more, and caused substantial property damage. The rupture on Line 132 occurred near mile point 39.28, at the intersection of Earl Avenue and Glenview Drive in San Bruno. About 47.6 million standard cubic feet of natural gas were released as a result of the rupture. The released natural gas was ignited after the rupture; the subsequent explosion created a crater about 72 feet long by 26 feet wide, and the resulting fire destroyed 38 homes and damaged 70. A ruptured pipe segment about 28 feet long was found about 100 feet away from the crater.

Probable Cause: The National Transportation Safety Board determines that the probable cause of the accident was the Pacific Gas and Electric Company's (PG&E) (1) inadequate quality assurance and quality control in 1956 during its Line 132 relocation project, which allowed the installation of a substandard and poorly welded pipe section with a visible seam weld flaw that, over time grew to a critical size, causing the pipeline to rupture during a pressure increase stemming from poorly planned electrical work at the Milpitas Terminal; and (2) inadequate pipeline integrity management program, which failed to detect and repair or remove the defective pipe section.

Keywords: Remote Operated Valves

Ntsbnumber: DCA10MP008

Report Number: PAR-11-01

Addressee Name: Pacific Gas and Electric Company

Addressee Status: Closed - Acceptable Action

Addressee Date Closed: 2015-12-01

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2012-03-13

Communication Type: Official Correspondence

Communication Contents: The NTSB understands that PG&E is in the process of modernizing its system and is using technology to help identify and respond to potential issues. PG&E’s automation of 11 shutoff valves in 2011, its plans to automate another 228 shutoff valves by the end of 2014, and its plans to enhance the SCADA information system are all positive actions. Pending completion of these efforts, Safety Recommendation P-11-27 is classified OPEN—ACCEPTABLE RESPONSE.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2012-08-29

Communication Type: Official Correspondence

Communication Contents: The NTSB notes that PG&E is modernizing its pipeline system and using technology to help identify and respond to potential issues. PG&E expects to complete installation of the automatic shutoff valves and remote control valves by the end of 2014. Further, PG&E will enhance its SCADA information system by including additional information related to pipeline pressures, valve positions, and gas flow rates. Pending completion of these efforts, Safety Recommendation P-11-27 is classified OPEN—ACCEPTABLE RESPONSE.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2012-02-06

Communication Type: Official Correspondence

Communication Contents: Correspondence control 201200077 was closed administratively. It was combined with 201100506. The response to correspondence controls 201100506/ 201200077 was mailed on 3/13/2012.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2014-09-25

Communication Type: Official Correspondence

Communication Contents: On August 29, 2012, based on information you provided in your May 23, 2012, update, we classified Safety Recommendations P-10-4, and P-11-26 and -27 “Open—Acceptable Response.” To date, we have received no further update from you detailing any action you may have taken to implement these recommendations; we would appreciate receiving one soon. For your convenience, I have enclosed the correspondence history for each of these recommendations. Please reply regarding your progress in implementing Safety Recommendations P-10-4, and P-11-26 and -27.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2015-05-15

Communication Type: Official Correspondence

Communication Contents: We understand that, although you did not complete the recommended action by the end of 2014 as expected, you have automated 208 valves, and expect to automate the remaining 9 valves this year. Pending completion of these efforts, Safety Recommendation P 11 27 is classified OPEN—ACCEPTABLE RESPONSE. We note that, to continually improve your operations, you also plan to analyze your system regularly and automate additional valves as needed.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2015-12-01

Communication Type: Official Correspondence

Communication Contents: We understand that you have completed the recommended installation of automatic shutoff and remote control valves, prioritizing segments for automated isolation and valve spacing by considering Potential Impact Radius as well as factors listed in 49 CFR 192.935(c). Although initial assessments indicated that you would install 228 valves, we note that, through detailed operational analysis and design improvements over the approximate 522 gas transmission pipeline miles, you were able to accomplish the automated isolation capability with only 217 valves. Your completion of this action satisfies Safety Recommendation P 11 27, which is classified CLOSED—ACCEPTABLE ACTION.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2012-01-27

Communication Type: Official Correspondence

Communication Contents: -From Christopher P. Johns, President: Pacific Gas and Electric Company (PG&E) fully embraces the safety recommendations outlined by the National Transportation Safety Board as part of the agencies review of the 2010 San Bruno pipeline accident. We recognize the importance of preventing a tragedy like this from occurring again and that is why we are committed to successfully implementing the NTSB's recommendations. To date, PG&E has taken numerous actions to make fundamental changes to our operations and management -all with a focus on putting public and employee safety first. In response to your September 26, 2011 letter, PG&E sent to you on December 22, 2011, an update on the progress we have made toward implementing the recommendations and the plans we have in place. This letter included an update on activities related to integrity management, emergency response, public awareness, threat assessment and recordkeeping, among other aspects of our operations and management. Since that time, members of our team have had the opportunity to meet with NTSB technical staff to discuss our submission and review our activities. We are grateful for the guidance and feedback provided at that meeting. As a result of those discussions, we recognize that it is incumbent upon us to provide a greater level of detail than was previously provided in the December 22, 2011 update. Therefore, we would like to take the opportunity to supplement our December 22, 2011 response by providing an amended response with the requisite detail within 45 days. PG&E will continue to meet with NTSB staff in the coming weeks to seek additional guidance to ensure that the update we provide is fully responsive and will allow the NTSB to more ably assess our progress and plans.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2015-03-23

Communication Type: Official Correspondence

Communication Contents: -From Nick Stavropoulos, Executive Vice President, Gas Operations: Pacific Gas and Electric Company (PG&E) continues to make significant progress implementing the safety recommendations outlined by the NTSB's investigation of the September 2010 San Bruno pipeline accident. The attached status report provides an update on PG&E's actions to address the remaining recommendations that are currently in "Open-Acceptable Response" status: 1. P-1 0-04: Strength Testing 2. P-11-26: Supervisory Control and Data Acquisition System Tools 3. P-11-27: Valve Automation Program PG&E believes that substantial progress has been made to implement these remaining open recommendations, and that one of the three is at the point that it may be considered for closure. We request that the NTSB review the information provided in this status report and consider closing recommendation P-11-26. In addition, we expect that recommendation P-11-27 will be ready to be considered for closure later this year, and the third recommendation, P-1 0-04, may be ready for consideration of closure in 2016. We are available to provide additional information or answer any questions you may have. PG&E thanks the NTSB for its continuing guidance and leadership as the company continues to work towards our goal of making PG&E's gas system the safest and most reliable in the nation. Update for P-11-27, End of 2014: PG&E has expedited installation of automatic shutoff and remote control valves as recommended. Prioritization of segments to be made capable of automated isolation, including determination of valve spacing, was made considering Potential Impact Radius (PIR) as well as factors listed in Title 49 Code of Federal Regulations 192.935(c). As indicated in previous correspondence, PG&E's plan to address this recommendation was to automate 228 valves. Through detailed operational analysis and design, approximately the same number of gas transmission pipeline miles (520) will have automated isolation capability by installing 217 valves rather than the original 228. Through the end of 2014 we have completed automation of 208 valves, and expect to complete the automation of the remaining 9 valves in 2015. Once the automation of those remaining 9 valves is complete, PG&E will request that the NTSB consider closing this recommendation. As a part of our effort to continually pursue improvements in our operations, PG&E will continue to analyze our system and automate additional valves as appropriate.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2015-10-27

Communication Type: Official Correspondence

Communication Contents: -From Nick Stavropoulos, President, Gas: Pacific Gas and Electric Company (PG&E) continues to make significant progress implementing the safety recommendations issued by the NTSB as a result of its investigation of the September 2010 San Bruno pipeline accident. The attached status report provides an update on PG&E's actions to address the remaining recommendations that are currently in "Open-Acceptable Response" status: 1. P-1 0-04: Strength Testing 2. P-11 -27: Valve Automation Program PG&E believes that substantial progress has been made to implement these remaining open recommendations, and that one of the recommendations may be considered for closure. We request that the NTSB review the information provided in this status report and consider closing recommendation P-11-27. In addition, we are completing additional analysis on the remaining work needed to complete recommendation P-10-04, indicating that completion will be later than 2016. Details of that analysis are included in this update. We are available to provide additional information or answer any questions you may have. Update for P-11-27, October 2015: PG&E has completed expedited installation of automatic shutoff and remote control valves as recommended. Prioritization of segments for automated isolation, including determination of valve spacing, was made considering Potential Impact Radius (PIR) as well as factors listed in Title 49 Code of Federal Regulations 192.935(c). As indicated in previous correspondence, PG&E's initial plan to address this recommendation was to automate 228 valves. This scope of work was based on PG&E's Pipeline Safety Enhancement Plan filing, which would allow remote or automatic isolation capabilities for 522 miles of PG&E's transmission pipeline network. Through subsequent detailed operational analysis and design improvements, approximately the same number of gas transmission pipeline miles (522) will now have automated isolation capability after installing 217 valves rather than the original 228. The installation of 217 valves providing remote or automatic isolation capability is now complete. Based on the completion of this milestone, PG&E requests that consideration be given to closing this recommendation. We have attached the following documentation for this completed work: • Listing of the 217 installed valves • Listing of the line segments and associated pipeline miles protected • Maps showing the valve locations and segments protected As indicated previously, PG&E continues to analyze our system and automate additional valves where it is determined to be beneficial. Thus far in 2015, PG&E has automated an additional12 valves on its system that provide enhanced protection to an additional31 miles of pipeline. Information on these additional valves and segments is included in the documentation provided.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2013-01-31

Communication Type: Official Correspondence

Communication Contents: -From Christopher P. Johns, President: Pacific Gas and Electric Company (PG&E) continues to make substantial progress implementing the safety recommendations outlined by the NTSB's investigation of the September 2010 San Bruno pipeline accident. This status report provides details on the actions we are taking to assure public safety remains the company's highest priority. In 2012, the NTSB evaluated PG&E's progress and closed four recommendations: 1. pe10-2: Search for Records 2. P-11-3: 911 Notifications 3. P-11-25: Emergency Response Procedures 4. P-11-28: Toxicology Testing In this report, we are submitting three additional recommendations for closure consideration by the NTSB: 1. P-10-3: MAOP Validation 2. P-11-24: Work Clearance Procedures 3. P-11-31: Public Awareness Program Continuous Improvement For recommendation P-10-3 (MAOP Validation), PG&E has completed the determination of the valid maximum allowable operating pressure (MAOP), based on the weakest section of the pipeline or component. The purpose of the MAOP validation is to ensure safe operation of natural gas transmission lines in class 3 and class 4 locations and class 1 and class 2 high consequence areas (HCA) that have not had a MAOP established through prior hydrostatic testing. In total, MAOP validation was performed for all 2,088 miles of these transmission pipelines. In addition to completing NTSB Recommendation P-10-3, PG&E is validating all remaining transmission lines in non-HCAs by mid- 2013. In 2012, PG&E completed the MAOP validation of 4, 199 miles of non-HCA pipelines. For recommendation P-11-24 (Work Clearance Procedures), PG&E has completed the revision and issuance of work clearance procedures that include requirements for identifying the likelihood and consequences of failure associated with planned work. The development of contingency plans is now a part of this process. PG&E's new procedure ensures accurate and completed clearance forms and requires field crews, control room operators and individuals who have been assigned the clearance supervisor role to have complete knowledge of the intended work and written clearance procedure. PG&E has completed recommendation P-11-31 (Public Awareness Program Continuous Improvement) through the development and incorporation of written performance measurements and guidelines into our Public Awareness Plan (PAP) for evaluating the plan and for continuous program improvement. The primary objectives include awareness, damage prevention and emergency response readiness. PG&E has also completed two portions of recommendation P-11-29 (Integrity Management Program): Revisions to PG&E's Risk Model and Risk Analysis Methodology. Other recommendations with significant progress highlighted in the attachment include: • (P-10-4)-ln 2012, PG&E strength tested or verified an additional 202 miles for a total of 417 miles since 2011 • (P-11-2)-PG&E installed 46 valves in 2012 (for a total of 59 valves since 2010) • (P-11-29)-ln addition to revising the Integrity Management Risk Model and Risk Analysis Methodology, PG&E is continuing to revise other portions of its integrity management program PG&E thanks the NTSB for both its continuing guidance and leadership as the company works to address the remaining safety recommendations. Please contact me directly if you have any questions. PG&E's valve automation program goes significantly beyond current code requirements and current industry practices as detailed in our Valve Automation Plan filed with the CPUC on August 26, 2011 and included as part of the May 2012 status report. PG&E's Valve Automation Program is being implemented in two phases and will install or upgrade a total of 530 valves (210 valves as part of Phase 1 and 330 valves as part of Phase 2) with automated shutdown (ASV) or remote shutdown (RSV) capability on transmission pipeline in Class 3 and Class 4 locations. The transmission automated valve field site installations include new pressure and flow data being transmitted to the SCADA system providing additional information that will be utilized by new SCADA control tools and technologies to provide PG&E's Control Room operators with better situational awareness of pipeline conditions. Upon completion, PG&E will have real-time knowledge of pipeline pressures at least every 5-8 miles on large diameter pipelines in Class 3 and 4 areas. Since 2010, PG&E has replaced, upgraded or automated a total of 59 valves through PSEP in the gas transmission system (13 valves in 2011 and 46 valves in 2012). Seventy-five valves are planned for 2013.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2012-05-23

Communication Type: Official Correspondence

Communication Contents: -From Christopher P. Johns, President: Pacific Gas and Electric Company (PG&E) is making substantial progress to implement the safety recommendations outlined by the National\ Transportation Safety Board's (NTSB) investigation of the September 2010 San Bruno pipeline accident. This status report details the actions PG&E has taken and will continue to take to assure public safety remains the company's highest priority in the operation of our natural gas transmission system. We have made many fundamental changes to the operations and management practices throughout our gas organization. Some of the more critical actions include: completion of the Maximum Allowable Operating Pressure validation of all 2,088 miles of high consequence area (HCA) pipelines; validation of 1,032 miles of non -HCA pipelines through April 2012; and automation of 36 valves. In 2011, PG&E conducted strength tests and verified strength test pressure records for a total of approximately 214.5 miles of pipeline. Additionally, from January through April 2012, an additional 37.6 miles have been tested or verified. PG&E's Pipeline Safety Enhancement Plan (PSEP), currently before the CPUC for approval in R.11-02-019, outlines our plan for testing or verifying records of 547 miles in 2012 -2014. PG&E has modified its 911 Notification Process to respond to the NTSB's suggestion that SCADA real time operating data and alarms serve as triggers for 911 notifications. We have developed a comprehensive emergency response procedure for large-scale emergencies on transmission lines, which identifies a single person in charge, outlines specific protocols and provides for drills and training. PG&E has also incorporated performance measures and guidelines to assure continuous improvement in our public awareness program. PG&E has initiated a complete assessment of every aspect of our transmission integrity management program including threat identification and assessment. Much more work lays ahead, but the progress to date gives us confidence that PG&E is on track to achieving the goal of regaining the trust of the public and our regulators by demonstrating our steadfast commitment to safety. The attachment to this letter provides a more detailed summary of each NTSB recommendation and the steps we have taken and continue to take to act upon them. If you have any questions, please contact me directly. PG&E has embarked on an aggressive program of valve automation that goes significantly beyond current code requirements and current industry practices as detailed in our Valve Automation Plan (Attachment P-11-27A) filed with the CPUC on August 26, 2011. PG&E will implement the Valve Automation Program in two phases with the second phase consisting of two components. Attachment P11-278 shows the locations and priorities for these phases. Phase priority was aligned with the two primary factors in segment selection: population density and PIR. Table 4-3 (pg. 4-38) of Attachment p. 11-27A shows the the various miles of PG&E gas transmission pipeline by Class, HCA and PIR value and highlights the focus of Phases 1, 2A and 2B. Phase 1 will be implemented in 2011 through 2014 and will provide automated isolation capability for 276 miles of pipe in Class 3 HCA locations with a PIR >300 feet and Class 4 locations with a PIR > 100 feet. To automate these pipe segments, an additional 246 miles of adjoining segments are required to be automated, of which 125 miles otherwise would have been automated in Phase 2. Phase 1 work results in a total of 522 miles of pipeline with automated isolation capability. It also includes automatic controls for pipelines crossing 16 active earthquake faults. Phase 1 work will provide automated isolation capability for 185 valves, and is planned to upgrade the controls for 43 valves that currently have some remote control capability. At least 50 new valves will be required to allow for this automation. PG&E will also install 30 new flow meters to provide necessary flow information to facilitate decision making on when to isolate pipe segments. Phase 2A consists of installing automated isolation capability on approximatley 535 miles of gas transmission line of which 345 miles are in Class 3 locations (approximately 130 valves). Phase 28 consists of installing automated isolation capability on approximately 725 miles of gas transmission line, of which 235 miles are in Class 3 locations (approximately 200 valves). PG&E anticipates that the CPUC's decision on the plan may be issued by the third or fourth quarter of 2012. Since October 2010, PG&E has automated 36 valves. PG&E plans to perform automation work on 46 valves in 2012 (23 completed year to date). Additionally, PG&E is enhancing the SCADA information system by including additional information related to pipeline pressures, valve positions and gas flow rates. (See PG&E's response to NTSB recommendation P-11-26.)

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 2011-12-22

Communication Type: Official Correspondence

Communication Contents: -From Christopher P. Johns, President: Pacific Gas and Electric Company (PG&E) has fully embraced the safety recommendations outlined by the National Transportation Safety Board (NTSB) as part of the agency's review of the September 2010 San Bruno pipeline accident. We at PG&E recognize the importance of preventing a tragedy like this from ever happening again, and we are grateful for the NTSB's guidance toward that goal. As requested in your September 26, 2011 letter, we are providing an update on the actions PG&E is taking, and the plans that are in place to implement the NTSB's thoughtful and thorough recommendations. These recommendations have prompted PG&E to take significant actions on many fronts, including pipeline leak and break identification, emergency response, integrity management, threat assessments, public awareness of pipeline safety measures, and recordkeeping. The NTSB's recommendations have helped propel PG&E to make fundamental changes to our operations and management-all intended to underscore our commitment to putting public and employee safety first. For example, we've completed Maximum Allowable Operating Pressure validation of more than 1,600 miles of high consequence area pipelines, with plans to complete all 2,000 miles by the end of January 2012. We are implementing a new data management system intended to address the NTSB's recommendations for traceable, verifiable and complete records. Additionally, PG&E has automated 11 shutoff valves in 2011. As part of the company's Pipeline Safety Enhancement Plan, which was presented for approval to the California Public Utilities Commission this year, PG&E has proposed automating a total of 228 valves through 2014. We've also updated our emergency response plans to reflect industry best practices and have begun training employees, public officials and first responders. In an effort to improve public gas safety awareness, we've mailed more than two million safety information letters to customers who live within 2,000 feet of a transmission pipeline. We realize we still have much to learn and do in the wake of the tragic San Bruno accident. As you'll see in the attachment, we have completed several of the recommendations and are in mid-stream on the remainder. We're working with urgency to complete all of the recommendations and we remain steadfast in our commitment to safety and to regaining the trust of the public and our regulators. The attachment to this letter provides a more detailed summary of each NTSB recommendation and the steps we are taking to act upon them. If you have any questions, please contact me directly. • PG&E is modernizing its system and using technology to help identify potential issues and address them quickly. Examples include: o Automated 11 shutoff valves in 2011 and a proposed total of 228 will be installed by the end of 2014 as part of PG&E's Pipeline Safety Enhancement Plan. o Enhancing the SCADA information system by including additional information related to pipeline pressures, valve position and gas flow rates. o The Company will be in compliance with any new requirements as established by a revised Pipeline Safety Act now pending approval by the White House.