23rd Annual Report, Executive Summary, Conclusions and Recommendations

History and Introduction

The Diablo Canyon Independent Safety Committee (DCISC) was established as part of the June 24, 1988 settlement agreement which arose from the rate proceedings for the Diablo Canyon Nuclear Power Plant (DCPP). The DCISC was formed in late 1989 with the appointments of Committee Members and began formal review activities and meetings on January 1, 1990. The original settlement agreement (D.88-12-083) was terminated by the California Public Utilities Commission (CPUC) in its decision to open the state electricity markets to competition on January 1, 1998; however, under the provisions of the Commission’s Decisions 97-05-088, issued on May 21, 1997, and 04-05-055, issued on May 27, 2004, the DCISC will continue to function and fulfill its responsibilities as established under the terms of the 1988 settlement agreement.

On May 27, 2004, the CPUC issued Decision 04-05-055. In its decision, the CPUC changed the nomination procedures by eliminating from the process the participation of PG&E and the Dean of Engineering at the University of California at Berkeley; modified the requirements for membership on the DCISC to add “knowledge and background in nuclear safety issues” to the “experience in the field of nuclear power facilities” and modified the DCISC’s mandate to require it to undertake public outreach in the community. The Decision concluded the DCISC should retain the discretion to determine how best to accomplish its mandate and that the DCISC shall otherwise continue to exist and to operate and continued funding through cost-of-service rates. To implement this directive the DCISC has continued to expand its public outreach as described in Section 8.0 Public Input and Outreach and continues to consider additional outreach activities.

On January 25, 2007, the CPUC issued Decision 07-01-028. The CPUC had previously adopted new practices and expectations for the DCISC without concurrently restating the Committee’s charter to reflect the changes. In its decision, the CPUC granted the DCISC application for authority to restate its charter including the incorporation into the Restated Charter of several terms, conditions, changes and clarifications necessitated by, and previously authorized by, the CPUC which govern the composition, responsibilities and operations of the Committee. In its decision, the CPUC found the Restated Charter to be in the public’s interest as it reflects the latest authority and obligations of the DCISC. The Committee’s application was unopposed.

The original settlement agreement provided for a three-member Independent Safety Committee for the purpose of “reviewing and assessing the safety of operations of DCPP”. The members serve three-year staggered terms and remain on the DCISC until a new appointment or their reappointment is made. To fill an expired term or a vacancy the CPUC issues a public notice soliciting interested persons. Under the revised process in accordance with the restated charter, candidates are selected by the CPUC from the applications plus the incumbent, if willing to serve. The candidates must be “persons with knowledge, background and experience in the field of nuclear power facilities and nuclear safety issues.” From the list of candidates, the new or returning member is appointed by the Governor of California, the Attorney General of California or the Chairperson of the California Energy Commission (CEC), whichever made the original appointment.

The Committee Members during this period were as follows:

Overview of Activities during the Current Period

The Committee regularly performs the following activities:

The DCISC issues a report for each reporting year, which runs from July 1 to June 30. The report is approved by the Committee Members at the fall public meeting following the end of the reporting period. The first six-month interim report and subsequent twenty annual reports covered the periods January 1, 1990–June 30, 2012.

This Twenty-third Annual report covers the period July 1, 2012—June 30, 2013.

Three public meetings were held in the vicinity of the plant in Avila Beach and San Luis Obispo, California during this reporting period. The technical items covered during these public meetings were selected by the DCISC based on the DCISC’s own priorities concerning which technical issues are important to cover. PG&E then responds by providing presentations and experts to participate in the public meetings as requested. The following significant items were reviewed:

Individual Committee Members and consultants reviewed many other items in nine fact-finding visits, inspections and tours at DCPP. The DCISC keeps track of past, current and future items for review in its Open Items List (Section 6.0 and Volume II, Exhibit F).

A DCISC Member visited officials from the Governor’s Office and the California Energy Commission to provide updates on DCISC activities, to discuss agency concerns and comments, and to provide copies of the Committee’s Annual Report.

Public input and questions were received at the public meetings, and by telephone, letter and E-mail. Members of the public spoke at two of the three DCISC public meetings. The DCISC has responded to all of their questions, concerns and requests during this period.

Overall Conclusion
The DCISC concludes that PG&E operated DCPP safely during the period July 1, 2012—June 30, 2013.

Specific Conclusions

Based on its activities, the DCISC has the following specific conclusions from the major review topics examined during the current reporting period (references to sections of this report are shown in parentheses). Conclusions are based on, but may vary from, information contained in Committee Fact-finding Reports in Exhibit D in Volume II of this report.

  1. The DCISC received regular reports on the Nuclear Regulatory Commission (NRC) Performance Indicators, DCPP License Event Reports (LERs) sent to NRC, and NRC Inspection Reports and Enforcement Actions (violations) at each of its public meetings as well as copies of these documents throughout the reporting period. The DCISC investigated selected reports at its fact-finding meetings.
  2. The Committee notes that, although the NRC concluded that, “Overall, Diablo Canyon Nuclear Power Plant, Units 1 and 2, operated in a manner that preserved public health and safety … ,” it identified 19 Non-cited Violations, one Severity Level IV violation, and NRC increased monitoring of a trend in Conservative Assumptions in Decision Making. The number of violations has increased, and DCPP has initiated strong actions to improve its regulatory performance.
  3. The DCISC is following this closely, specifically review of DCPP NRC regulatory performance during the next reporting period, paying attention to the number of DCPP License Event Reports and to the trend in Conservative Assumptions in Decision Making. (Volume I, Section 3.6)
  1. DCPP appeared to have an effective Operations Function. Time Critical Operator Actions and Nuclear Reactivity were being controlled properly. Some weaknesses in Human Performance had been identified by the station’s Quality Verification (QV) Group, and similar issues had also been noted to some degree by QV in other station departments. (Volume I, Section 4.1.3)
  2. Actions taken to reduce the number of adverse events due to maintenance were nearing completion. Maintenance performance indicators appeared to be improving. Actions were being taken to maintain a well-staffed and trained maintenance workforce and to communicate more openly and effectively with worker level personnel. (Volume I, Section 4.2.3)
  3. Overall, DCPP’s engineering program continued to be strong. DCPP’s Boric Acid Corrosion Control Program appeared to be effective in identifying, documenting, and repairing components leaking boric acid. The DCPP Environmental Qualification (EQ) program appeared to be healthy. No significant EQ problems were noted. Considerable progress was made in the DCPP Licensing Basis Verification Project regarding the various Licensing Basis Reviews conducted since the end of 2011. Engineering design quality was affected to some extent during Outage 1R17 by issues pertaining to three plant modifications. Station performance in the area of Configuration Management, which was acceptable, appeared to have been influenced by design quality and the number of temporary modifications installed in the plant. (Volume I, Section 4.3.3)
  4. The apparent negative trend in the station’s non-outage human performance error rate experienced during the last half of 2011 was actually due to more emphasis on reporting errors. DCPP’s human performance error rate during the first quarter of 2012 shows an improving trend compared to the last half of 2011, and the 2012 goal is set to a higher standard than for 2011. DCPP’s human performance training facility appears to be an effective environment for training individuals in proper human performance techniques and reinforcing the importance of error-free work in a nuclear station. The DCISC will continue periodic reviews of human performance as dictated by station events and overall performance. (Volume I, Section 4.4.3)
  5. DCPP’s Nuclear Safety Culture Health Monitoring process and Nuclear Safety Culture Monitoring Panel/Report appeared rigorous and effective in measuring and improving the plant’s nuclear safety culture in accordance with industry’s Eight Nuclear Safety Culture Principles and supporting Attributes. The DCISC will monitor this process on a continuing basis. (Volume I, Section 4.5.3)
  6. DCPP’s Performance Improvement Program continues to be strengthened with the Performance Improvement Action Plan, a multi-faceted plan to integrate the results of several assessments and reviews of the program and by dedicated management performance improvement oversight boards. (Volume I, Section 4.6.3)
  7. The DCISC observed a utility-evaluated emergency drill and an emergency exercise evaluated by both NRC and FEMA. This included observing a Joint Information Center (JIC) mock briefing during one of the drills. The briefing was effectively and professionally conducted, and it stimulated productive discussion by the JIC participants. The control room crews in the simulator and the remainder of PG&E’s emergency organizations were evaluated to have performed effectively both during a utility evaluated emergency drill and also during an emergency exercise evaluated by NRC and FEMA. The DCPP Emergency Planning Workshop for government emergency response organization personnel appeared to have been beneficial and effective. (Volume I, Section 4.7.3)
  8. The DCISC did not review DCPP Probabilistic Risk Analysis during this period. (Volume I, Section 4.8.3)
  9. DCPP has developed a satisfactory plan for addressing areas needing improvements identified in the Institute for Nuclear Power Operations August 2011 evaluation and for preparing for its August 2013 evaluation. (Volume I, Section 4.9.3)
  10. DCPP radioactivity releases during this period, as in previous periods, were very small fractions of Technical Specification and regulatory limits. Overall, the DCPP Radiation Protection Program appears effective. The DCISC will continue to monitor DCPP’s progress in radiation protection. (Volume I, Section 4.10.3)
  11. Quality Verification (QV) appeared to be effectively performing its role as an independent assessor of site activities with a special focus on safety. QV persisted in aggressively identifying station quality issues and following up with station supervision to bring about resolution. (Volume I, Section 4.11.3)
  12. The DCISC observed the receipt, handling, inspection and storage of two DCPP new nuclear fuel assemblies and concluded that these activities were effectively performed and that great care was taken to protect new fuel assemblies during the entire evolution. (Volume I, Section 4.12.3)
  13. DCPP’s Equipment Reliability Program is strong and in good health; however, there continue to be equipment reliability problems, which the plant is addressing in its strategic and tactical plans. (Volume I, Section 4.13.3)
  14. DCPP has several activities which enhance its Organizational Effectiveness, such as its emerging issue process to organize, communicate, and correct issues involving equipment reliability and human performance; its Operating Plans; and its membership in STARS, a consortium of seven nuclear plants for sharing of resources. (Volume I, Section 4.14.3)
  15. As in previous reporting periods, DCPP has dealt effectively with most equipment and system problems and is focused on improving system health. Systems that are the sources of emergency electrical power to the station’s vital electrical equipment, the station’s Emergency Diesel Generators and the 230 kV system that is supplied from the offsite electrical grid, were found to be operational but have been a focus of station and NRC attention. DCPP’s Plant Health Committee has been improved to focus more on system/component health and meets more frequently, and overall system health has improved. The System Engineer/Component Program continues to be effective. (Volume I, Section 4.15.3)
  16. The DCISC did not review DCPP Steam Generators during this period, because DCPP’s SG tubes had shown excellent inspection and test results in Outages 2R15 and 1R16 and are considered to be in excellent health, and no SG tube inspection was required or conducted in 1R17 or 2R17. (Volume I, Section 4.16.3)
  17. DCPP conducted a generally safe refueling outage 1R17. Collective radiation dose (less than 100 person-rem) was the lowest achieved during any Unit 1 refueling outage in plant history. The scope of outage work was large; hence it increased the length of the outage, primarily due to the replacement of the Process Control System.
  18. The DCPP Outage 2R17 Outage Safety Plan was a comprehensive and detailed document describing the schedule and steps in the outage, noting which steps are identified as high risks of core boiling or damage as a result of losing electric power and/or cooling to the reactor core and Spent Fuel Pool, and discussing the extent of systems that are available to maintain the risk of damage to the reactor core at acceptably low levels.
  19. The 2R17 DCPP Refueling Outage was successful in meeting or exceeding almost all goals. The large outage scope was similar to that in Outage 1R17. There were no significant nuclear safety events or concerns. Of note, 2R17 experienced the lowest radiation dose (approximately 25 person-rem) in Unit 2 outage history. (Volume I, Section 4.17.3)
  1. The DCPP safety-security interface appears to be appropriately designed and implemented. (Volume I, Section 4.18.3)
  2. The DCISC did not review the DCPP Independent Spent Fuel Storage Installation during this period. (Volume I, Section 4.19.3)
  3. DCPP’s newly issued Personnel Seismic Safety Action Plan is impressive in its comprehensiveness, objectives, completion dates, and accountability. Their benchmarking of UC Berkeley and Lawrence Berkeley Laboratory is appropriate. The DCISC will continue to follow this issue closely through completion by DCPP. (Volume I, Section 4.20.3)
  4. DCPP’s Fire Protection Program and Systems have been considered satisfactory, though not without issues, in the past by NRC and the DCISC. DCPP is strengthening Fire Protection by transitioning to NRC regulations under the National Fire Protection Association Standard 805, by reviewing its implementation of regulatory requirements in the DCPP Licensing Basis Verification Project, and by correcting issues found by its Self-Assessment and NRC’s Triennial Fire Protection Inspection. (Volume I, Section 4.21.3)
  5. DCPP appeared to be taking focused action to address underlying causes for licensed operator candidate failures on the NRC licensing examinations in the previous reporting period. Station documentation indicated that Maintenance workers are trained and qualified in a timely fashion to perform their assigned tasks. Training programs receive extensive oversight by plant management from the perspectives of both curriculum and results. The DCISC observed a “continuing training lesson” on the components of the Fuel Transfer System, and found that it was well conducted. The DCISC also observed simulator training session and found that it presented a fast-paced, varied, and challenging scenario. Actions taken by the operating crew appeared to be appropriate. DCPP should consider occasionally running scenarios on the simulator and allowing the operating crews in training to observe how the plant responds without their intervention. The DCPP Mechanical Maintenance Training on rotating equipment shaft alignment appeared comprehensive and effective. The process for development, administration, and control of NRC licensed reactor operator and senior reactor operator biennial requalification examinations appeared to be well structured, thorough, and tightly administered (Volume I, Section 4.22.3)
  6. During this DCISC reporting period, the DCPP License Renewal Project remained on hold for completion in 2015. The DCISC will resume its review upon the restart of Licensing Renewal activities. (Volume I, Section 4.23.3)
  7. A contractor working under the aegis of the California State Water Resources Control Board has completed the first of two phases of examining alternatives to once through cooling (OTC) at DCPP. Many options were considered and eliminated in Phase 1, and a smaller number have been selected for review in Phase 2. All of these remaining options would require major changes to the site, lengthy shutdowns of the two units, heavy capital expenditures, and potentially adverse impacts to operational safety. The DCISC intends to follow this issue over the next year or more and to review the operational safety implications of any proposal that would replace OTC with a different technology. (Volume I, Section 4.24.3)
  8. After the Fukushima nuclear accident in Japan in March 2011, both the NRC and the industry developed several technical initiatives that respond to various lessons-learned. The DCPP plant established a “DCPP Fukushima Project” to provide a focus for the plant’s responses. This Project’s organization plans and accomplishments to-date for responding to regulatory orders and industry guidance are extensive and impressive. The DCISC will follow up periodically to assess DCPP’s progress. (Volume I, Section 4.25.3)
Concerns are items which, while not necessarily warranting recommendations, the DCISC believes need continuing Committee review and improvement or attention by PG&E. Concerns are monitored more actively and at a higher-level by the Committee than other items. The DCISC concerns are as follows:
  1. DCPP’s regulatory performance appears to have degraded due to an increased number of Licensee Event Reports, a continuing high number of Non-Cited Violations, and an increased trend of violations in the NRC Cross-Cutting Aspect of Conservative Decision Making. (Volume I, Section 3.6) (See the related Recommendation R13-1 below.)
  2. DCPP’s Emergency Diesel Generators of both units have been experiencing long-standing problems pertaining to component deterioration and obsolescence as well as incompatibilities between regulatory requirements and existing design requirements. In addition, the offsite electrical demand on the 230 kV System, which also supplies DCPP, has been increasing. This, in turn, has raised the question of whether situations could arise in which the system might have difficulty meeting DCPP’s design on-site vital electrical load requirements. The station is continuing to focus on these issues, and the DCISC will continue to do so as well. (Volume I, Section 4.15)
  3. The discovery in 2008 of a new earthquake fault just west of the plant site, the “Shoreline Fault,” has resulted in a multi-year technical effort to understand the fault and its possible effect on the plant’s ability to remain safe during a potential earthquake on that fault. The tentative conclusion of the NRC is that the plant’s current design is adequate, and the DCISC concurs. However, important technical work is ongoing to provide additional information about this fault and its potential effects. The DCISC has followed this issue from the start and will continue to do so. (Volume I, Section 4.20)
  4. Although the studies examining the possible replacement of a Once Through Cooling capability for DCPP’s main condensers are still in progress, the DCISC expresses a significant initial concern regarding the potential impact that such a modification would have on nuclear plant safety and reliability. (4.24)
  5. Though DCPP is performing well in implementing Fukushima initiatives, the significant number of changes will be challenging to learn, implement, and operate effectively. (Volume I, Section 4.25)
DCISC recommendations are listed below along with references to sections where recommendations originate. Recommendations are based on, but may vary from, information contained in Committee Fact-finding Reports in Exhibit D, Volume II of this report.
Recommendation R13-1
Because of the relatively large increase in Licensee Event Reports from the previous reporting period, continuing high number of Non-Cited Violations, and the number of items in the Conservative Decision Making Cross-Cutting Aspect, the DCISC recommends that DCPP review the effectiveness of its Regulatory Excellence Action Plan.
Basis for Recommendation:
The following trends of License Event Reports (LERs) and Non-Cited Violations (NCVs) indicate degrading or non-improving regulatory performance:

Recommendation R13-1. License Event Reports (LERs) and Non-Cited Violations (NCVs)
Reporting Period LERs NCVs
7/1/08–6/30/09 5 18
7/1/09–6/30/10 7 14
7/1/10–6/30/11 10 36
7/1/11–6/30/12 6 14
7/1/12–6/30/13 12 19

Additionally, the four NCVs in the NRC H.1(b) Conservative Decision Making Cross-Cutting Aspect have raised the NRC monitoring level but have not yet triggered an NRC Significant Cross-Cutting Aspect; however, more related NCVs will trigger it. The DCISC believes augmented actions by DCPP are needed to avoid problems in this area.
Recommendation R13-2:
The DCISC recommends that DCPP evaluate the various constraints on how fast spent fuel bundles can be loaded into the Independent Spent Fuel Storage Installation (ISFSI), and develop an estimate of, and the rationale for, the practical limit on the number of spent fuel bundles that can be loaded into the ISFSI on a per year basis.
Basis for Recommendation:
The issue of storing spent fuel in the spent fuel pool with high-density racks has been highlighted by the California Energy Commission in its annual Integrated Energy Policy Reports, as well as in numerous studies conducted by other organizations. The DCISC has reviewed these issues in several of its fact-finding meetings. The DCISC has been informed that constraints on accelerating the loadings into the ISFSI are many: thermal considerations requiring spent fuel to remain in the pool for a several-year initial period; thermal shielding requirements imposed by federal regulations; refueling outages considerations; and equipment and personnel availability, to name a few. However, as of now no estimate is available concerning the practical and regulatory limits on the speed at which spent fuel can be loaded into the ISFSI. This information would be very useful in examining issues of spent fuel pool safety.

Finally, the DCISC appreciates PG&E’s cooperation in arranging and providing information for DCISC fact-finding meetings and tours at DCPP and for the high quality and professional presentations at DCISC public meetings.

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.