21st Annual Report, Pacific Gas and Electric“s Response to the Diablo Canyon Independent Safety Committee Twenty-First Annual Report on the Safety of Diablo Canyon Nuclear Power Plant Operations–July 1, 2010, to June 30, 2011

January 31, 2011

PG&E Letter ISC-12-001

Dr. Peter Lam
c/o The Diablo Canyon Independent Safety Committee
857 Cass Street, Suite D
Monterey, CA 93940

Response to the Diablo Canyon Independent Safety Committee Twenty-First Annual Report on the Safety of Diablo Canyon Nuclear Power Plant Operations–July 1, 2010, to June 30, 2011

Dear Dr. Lam:

Pacific Gas and Electric Company’s (PG&E) response to the Diablo Canyon Independent Safety Committee’s (DCISC) Twenty-First Annual Report on the Safety of Diablo Canyon Operations for the period of July 1, 2010, to June 30, 2011, is provided in the enclosure to this letter.

We are pleased that the DCISC has once again concluded that PG&E operated the Diablo Canyon Nuclear Power Plant (DCPP) safely during the report period. As you are aware, operating the plant conservatively to protect public health and safety is our highest priority, and we will continue to ensure that we fulfill this commitment.

As discussed in the enclosure, we have reviewed and are taking actions to address your recommendations. We welcome the Committee’s recommendations, and believe that addressing them will further contribute to the safe operation of DCPP.

James R. Becker




Due to the substantial increase in the numbers of NRC Non-cited Violations and Severity Level IV Violations over the last two reporting periods and because the NRC Substantive Crosscutting Issue in Problem Identification and Resolution still exists, the DCISC recommends that DCPP re-examine its earlier Root Cause Analysis for effectiveness and consider an independent review of its corrective actions by Quality Verification, the Nuclear Safety Oversight Committee, or the Institute of Nuclear Power Operations in an assist visit. (3.5)

PG&E shares the DCISC’s concern about the trend in the number of violations assigned to Diablo Canyon by the NRC.

PG&E recognizes this gap to excellence and is addressing it via one of the five station initiatives identified in the DCPP 2012–2015 Operating Plan. The Regulatory Excellence Initiative describes how Diablo Canyon organization will improve its regulatory performance by fully understanding regulatory requirements, recognizing gaps and risks, taking prompt interim action to close the gaps, and applying Performance Improvement techniques to address the risks. This will include closing the substantive cross-cutting issue in problem evaluation thoroughness, accurately identifying all reportable conditions, making timely notifications, and improving communications with NRC Resident and Regional Inspectors. The strategies we will use to achieve this are:

Specific actions to implement these strategies are tracked via the Regulatory Excellence Action Plan.

The DCISC recommended that DCPP initiate and promptly complete its first self-assessment of the significant gap in the thoroughness and rigor of its engineering evaluations, which was to have been completed by the end of 2010. (4.3.3)

PG&E agrees with the DCISC regarding the continued monitoring and assessment of the effectiveness of the corrective actions taken to improve the thoroughness and rigor of engineering (and other station) evaluations.

The self-assessment identified in the recommendation was cancelled at the direction of the Director, Engineering Services. The subject self-assessment was considered redundant to effectiveness evaluation required by the Corrective Action Program.

On November 17, 2011, PG&E completed, and the Corrective Action Review Board approved, an interim effectiveness evaluation for the corrective actions to prevent recurrence for the Root Cause Evaluation associated with problem evaluation thoroughness in November 2011. This assessment was performed because one of the corrective actions to prevent recurrence will not be complete until the end of 2014–The Licensing Basis Verification Project (LBVP). PG&E wanted to assure that the other actions taken were providing the desired result.

The assessment concluded, “ … that significant progress has been made to date regarding station program improvements and ownership. However, inconsistency in the application of the generic governance across station programs is preventing full achievement of the desired outcomes. Interim corrections to achieve the desired long term outcomes defined by the RCE effectiveness criteria are necessary.” Actions to address these observations are being tracked in the Corrective Action Program and as part of the Evaluation Thoroughness Action Plan. All tasks identified to-date in the action plan, with the exception of the LBVP, will be complete by June 2012. PG&E will continue to monitor the effectiveness of actions taken and make adjustments as necessary.

DCPP’s Post Earthquake Response Procedure should be expanded to require examination of Spent Fuel Pool (SFP) levels after an earthquake and sampling locally for indications of possible SFP liner leakage. DCPP should also consider providing permanently installed, remote wide-range SFP level monitoring capability. (4.20.3)

PG&E agrees with the DCISC that the lessons learned from the events at the Fukushima Daiichi power plant should be evaluated and incorporated at Diablo Canyon, as determined to be appropriate by those evaluations.

Casualty Procedure CP M-4, “Earthquake” Revision 27 was made effective on January 19, 2012 as a result of this recommendation. When Spent Fuel Pool level indication is suspect, the procedure directs the dispatch of an operator to verify that the Spent Fuel Pool levels are stable and that adequate Spent Fuel Pool cooling is in service.

Diablo Canyon has representatives participating in a number of nuclear industry efforts to assure that all applicable lessons learned are captured and acted upon. These industry efforts, as well as soon-to-be-issued direction from the Nuclear Regulatory Commission will result in a significant number of actions (including enhanced Spent Fuel Pool level monitoring capability) that, once finalized, the Diablo Canyon Organization will implement to assure the continued safe operation of the facility.

DCPP needs to develop and implement a schedule for taking the necessary actions to brace furniture appropriately throughout the station, and to better educate plant staff about seismic hazards and seismic safety. (4.20.3)

PG&E agrees with the DCISC that the safety of Diablo Canyon Plant staff, including from seismic threats, is of paramount importance.

It should be noted that PG&E maintains high levels of seismic awareness and control of materials within the power plant itself via the Seismically Induced System Interaction Program. The concerns raised by the Committee revolve around similar concerns in the context of office environments.

PG&E’s standard to address this concern is Utility Procedure: RE-2002P-01, “Bracing Cabinets and Storage Racks Procedure.” Diablo Canyon is committed to comply with this standard.

The examples noted by the Committee in a project work area also do not meet the Diablo Canyon standards for general area housekeeping. This deviation has been entered into, and will be addressed by, the Corrective Action Program.

With regard to the more general concern of preventing office furniture from tipping during a seismic event, Diablo Canyon believes that this concern has been addressed by an alternative to bracing. The file cabinets that were observed in the Control Room briefing area (as well as the remodeled floors in the Administration Building) were procured with counterweights installed in base of the units. The weights are sufficient to assure a sufficiently low center of gravity that they will not tip. They comply with the requirements contained in the above-referenced procedure without additional bracing.

One of five station initiatives identified in the DCPP 2012–2015 Operating Plan, the Site Modernization Initiative assures the station remains focused on a number of areas including the concerns identified in this recommendation. It provides a schedule for assuring that all Diablo Canyon-related facilities are upgraded to meet current standards.

For more information contact:

Diablo Canyon Independent Safety Committee
Office of the Legal Counsel
857 Cass Street, Suite D, Monterey, California 93940
Telephone: in California call 800-439-4688; outside of California call 831-647-1044
Send E-mail to: dcsafety@dcisc.org.