Substation Inspection Program

1. Substation Inspection Program

2. Mission Substation Incident • The event occurred on December 20, 2003 during the peak Christmas shopping season • A fire occurred in a 12kV cable feeding a switch on the second floor of a 3 story indoor substation • The substation receives power from 115kV underground cables and distributes 4 and 12kV within SF • The fire caused a complete outage of the substation, effecting about 100,000 customers, some for as long as 32 hours

3. Timeline • 15:51—The network cable failed explosively. No customers lost power • 15:51—A circuit breaker protecting the “N” bus also operated • 17:24—The fire migrated to a bus duct above the switch and the burning bus caused the circuit breaker protecting another switch cabinet to operate, causing an outage to 3112 customers

4. Timeline • 17:42—A switchman was sent to Mission substation to investigate the incident • 17:57—All transmission circuit breakers were opened, causing an outage to approximately 100,000 customers

5. Section of Damaged “N” Bus

6. The Damaged Cable

7. Investigation • CPUC assembled a team of engineers, analysts and attorneys to investigate the incident. • During one of the interviews, the CPUC asked if there had been any previous incidents at Mission Substation involving fire. • Yes, a previous incident occurred in 1996. • The incident was very similar to the fire that occurred in 2003.

8. Mission Substation Incident-1996 • A vertically installed PILC cable caught on fire • Smoke from that fire caused a short across the “N” bus • Around 1:00am, a PG&E employee went to the substation to use a restroom and discovered the fire.

9. Mission Substation Incident-1996 Three key recommendations from that investigation were: • Initiate fire penetration sealing program between floors. • Review procedures for responding to abnormal operating conditions, such as circuit breaker trips • Evaluate a cost effective method of smoke detection.

10. Mission Substation Incident • PG&E did not implement any of the key recommendations at Mission Substation by the time the incident occurred in 2003. • CPUC published its report • CPUC moved toward an Order Instituting Investigation (OII)‏

11. Mission Substation Incident • PG&E disputed our finding that the remedial measures would have made a difference. • PG&E decided to settle the dispute via the Mission substation settlement agreement.

12. Settlement • PG&E, the City and County of San Francisco and the CPUC agreed that PG&E will pay $6.5 million, to various causes: • $500,000 to the States General Fund • $3.0 million for reliability improvements to PG&E • $750,000 for a fire safety program for SFFD • $750,000 for CCSF to build needed infrastructure to improve public safety • $1.0 million for a Hunters Point Substation Improvement Program • $500,000 to support the Commission’s undertaking to create a substation inspection program.

13. Creation of Inspection Program • Meet with Five Investor Owned Utilities (PG&E, PP&L, SCE, SDG&E & SPP) • Attended Training and Conferences concerning Substations and Equipment • Attended CAISO audits of Utility’s Substation Programs

14. Prescriptive Benefits Easy to Audit Easier to Understand Easily defined criteria Problems May require work to be done that is not needed Does not account for differences Performance Benefits Gives utilities flexibility Accounts for differences Construction Environment Operation Problems Harder to audit Two Choices

15. Picked Middle Ground • Proposed General Order has both Prescriptive Parts and Performance Based Parts

16. The Proposed General Order(As written today) • Six Sections • General Provisions • Definitions / Acronyms • Construction Requirements • Operation and Maintenance Program • Reporting Requirements • Maps and Drawings • 13 pages

17. Purpose Applicability Scope of Rules* Investigation of Accidents Saving Clause “These rules are not intended as complete construction, inspection, or maintenance specifications, but embody only the minimum requirements which are most important from the standpoint of safety and reliability of service.” Section IGeneral Provisions

18. Section IIDefinitions / Acronyms • Defines key terms used throughout the general order • Example “Visual Inspections” are inspections that are designed to identify obvious problems and hazards.

19. Section IIIConstruction Requirements • General Provisions • Guarding • Marking • Safety Factor Requirements • Secondary Oil Containment • Switches

20. Section IVOperation and Maintenance Program • General Provisions • Inspection Procedures • Maintenance Procedures

21. Section VReporting Requirements • Operation and Maintenance Plan – Utilities must file a copy of their Operation and Maintenance Plan yearly • CPSD Audits – Pre Inspection Report due 30 Calendar Days before Audit

22. Section VIMaps and Drawings • Types of Maps and Drawings • Single Line Diagram • Meter and Relay Drawing • Physical Layout (e.g. Architectural drawings) • Map/Drawing Updates • 180 Days

23. Creation of Inspection Program(The Future) • Before an OIR is opened will meet with: • Electric Utilities • Rail Transit Agencies • Legal Review of the Proposed General Order • Open an OIR – • Workshops • Briefings • Hearings??? • Start Inspections

24. Questions