ML20206S666
| ML20206S666 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 10/26/1998 |
| From: | Seale R Advisory Committee on Reactor Safeguards |
| To: | Shirley Ann Jackson, The Chairman NRC COMMISSION (OCM) |
| References | |
| ACRS-SL-0464, ACRS-SL-464, NUDOCS 9905210194 | |
| Download: ML20206S666 (10) | |
Text
'
1 4
p ur SL-0464
- d. +
Pi %, UNITED STATES pDR j
4 8 o NUCLEAR REGULATORY COMMISSION l'
(g ADVISORY COMMITTEE oN REACTOR SAFEGUARDS wAsHWGTON. D. C. 20655 i
October 26,1998 l
i l The Honorable Shirley Ann Jackson i
Chairman ~ '
U.S. Nuclear Regulatory Commission .
Washington, D.C. 20555-0001 l .
Dear Chairman Jackson:
SUBJECT:
SUMMARY
REPORT- FOUR !dVNDRED FIFTY-FIFTH MEETING OF THE l ADVISORY COMMITTEE ON REACTOR SAFEGUARDS, SEPTEMBER 2-4, l 1998, AND OTHER RELATED ACTIVITIES OF THE COMMITTEE i 1 During its 455th meeting, September 2-4,1998, the Advisory Committee on Reactor Safeguards (ACRS) discussed several matters and completed the following report and
!- letters. In addition, the Committee authorized Dr. Larkins, Executive Director, to transmit the memorandum noted below:
l REPORT 1
l
- Emeroency Core Coolina System Strainer Blockaae (Report to Shirley Ann Jackson, Chairman, NRC, from R. L. Seale, Chairman, ACRS, dated September 14, l 1998)
LETTERS 1
- Apolication for Power Level increase for Edwin I. Hatch Nuclear Power Plant Units 1 and 2 (Letter to L. Joseph Callan, Executive Director for Operations, NRC, from R. L. Seale, Chairman, ACRS, dated September 15,1998)
- A Push for a New Standard in Runnino Nuclear Plants (Letter to Dr. Najmedin i
Meshkati from R. L. Seale, Chairman, ACRS, dated September 14,1998)
MEMORANDUM
= Prooosed Final Rulemakina Chanaes to Paraaraoh (h) of 10 CFR Part 50.55a.
" Codes and Standards" (Memorandum to L. Joseph Callan, Executive Director for Operations, NRC, from John T. Larkins, Executive Director, ACRS, dated September 9,1998) }
9905210194 981026 ' .
SO\ 9 SL 046 PDR Drs!CFATED ORIGINAll N R$.
~
a.a uDyp 8 L.. - . _ . . _
j
. The Honorable Shirley Jackson 2 HIGHLIGHTS OF KEY ISSUES CONSIDERED BY THE COMMITTEE
- 1. Power Level increase Reauest for Edwin I. Hatch Nuclear Plant. Units 1 and 2
]
The Committee heard presentations by and held discussions with representatives of the Southern Nuclear Operating Company (SNC), General Electric Nuclear Energy (GENE), and the NRC staff regarding the application by SNC for a power level increase of eight percent pursuant to the GENE Extended Power Uprate Program. Two years ago, SNC obtained a five percent power level increase for i Hatch Units 1 and 2 under the original GENE generic uprate program. In addition to the required deterministic analyses, SNC performed probabilistic risk assess-ments and uncertainty evaluations to determine the impact of both power uprates on plant risk. The Committee agreed with the staffs proposed approval of the requested power increase for the Hatch Units.
As an adjunct to this uprate review, the staff informed the Committee that, based on prudent regulatory practice, it will require licensees requesting substantial uprates to perform a risk analysis based on use of the existing plant PRAs. The acceptance criteria specified in Regulatory Guide 1.174 will be used as general guidance for the staffs evaluation of these risk analyses.
i Conclusion i
The Committee issued a letter to the Executive Director for Operations, dated ;
September 15,1998, on this matter. i
- 2. Emeroency Core Coolina System Strainer BlochaEt The Committee heard presentations by and held discussions with representatives ;
of the NRC staff concerning the past, present, and future activities associated with the emergency core cooling system strainer blockage issue. The Committee and the staff discussed debris generation and transport analyses, experimental verifications, strainer designs, and net positive suction head analyses.
Conclusio_r1 The Committee issued a report to Chairman Jackson, dated September 14,1998, on this matter.
The Honorable Shirley Jackson 3
- 3. Establishina a Benchmark on Risk Durina Low-Power and Shutdown Operations L The Committee heard presentations by and held discussions with representatives of the NRC staff and the Electric Power Research Institute (EPRI) regarding the status of staff benchmarking and industry evaluation of risk during low-power and shutdown operations. The Committee discussed EPRI TR-109014,"An Analysis of Loss of Decay Heat Removal (1989-1996), Outage Risk Assessment and l Management (ORAM) Technology." The staff informed the Committee that planning and project initiation of its benchmark study has been delayed until January 1999 due to the reprioritization of work related to Chairman Jackson's tasking memoran-dum dated August 7,1998.
i Conclusion This briefing was for information only. The Committee plans to continue its review -
! of these n'atters during future meetings.
l
- 4. Imoset of PRA Results and insiahts on the Reaulatory System The Committee heard presentations by and held discussions with representatives of the NRC staff and the Nuclear Energy Institute regarding issues in the Staff i
Requirements Memorandum (SRM) dated April 20,1998, concerning situation-specific cases where probabilistic risk assessment (PRA) results and insights have improved the existing regulatory system and specific areas in which PRA, when applied properly, can have a positive impact on the regulatory system.
- The ACRS Subcommittee on Reliability and Probabilistic Risk Assessment met on August 26,1998, to discuss staff and industry initiatives regarding these matters.
The Subcommittee also considered staff plans to address stakeholder concerns and Congressional interest in NRC activities as discussed in the EDO's August 25,1998 memorandum, which responded to Chairman Jackson's memorandum dated August 7,1998.
Conclusion l
The Committee plans to prepare a report to the Commission during the September 30-October 2,1998 ACRS meeting, on this matter.
t
c ,
1
, The Honorable Shirley Jackson 4 t
- 5. Proposed Resolution of Generic Safety Issue 171. "Encineered Safety Feature Feilure from Loss of Offsite Power Subseouent to a Loss-of-Coolant Accident" The Committee heard presentations by and held - discussions with the l representatives of the NRC staff regarding the proposed resolution of Generic Safety issue 171, " Engineered Safety Feature Failure from a Loss of Offsite Power l Subsequent to Loss-of-Coolant Accident (GSI-171)." The staff stated that the initial GSI-171 prioritization reported in NUREG-0933 was based on conservative i assumptions in the probabilistic risk analysis that resulted in a HIGH priority ranking.
Subsequent evaluations of key assumptions noted that some equipment failure hypotheses were unrealistic and that estimated core damage frequencies (CDFs)
I were too high. Probabilistic analyses performed by Brookhaven National Laboratory (BNL) concluded that the CDF contribution of a LOCA/ LOOP accident can vary by two orders of magnitude between BWRs and PWRs, depending on the plant design characteristics of load-shedding / load-energization features. The dominant contribution was block-loading to the offsite power supply and block-loading to the emergency diesel generators (EDGs) without load shed following a LOCA. On the basis of the BNL study, the staff has proposed reassigning GSI-171 a DROP priority l ranking and discontinuing work in this area.
l Conclusion The Committee decided to continue its review of this matter during a future meeting.
l
- 6. Meetina with the Director of the NRC Office for Analysis and Evaluation of
~
Operational Data (AEOD)
Mr. Thomas T. Martin, Director of the Office for Analysis and Evaluation of Operational Data (AEOD), and his staff briefed the Committee regarding AEOD
, activities. Mr. Martin stated that AEOD was created to provide a strong independent l capability to analyze and evaluate operational safety data associated with activities l licensed by the NRC. The AEOD staff discussed its programs for risk-based analysis of reactor operating experience including performance indicators and accident sequence precursors. These programs have been applied to analyze data and information in a consistent manner over a number of years. A substantial reduction in safety-significant operational events since 1985 was apparent. The number of initiating events resulting in scrams has declined significantly as was reflected in fewer and less complicated plant transients. Other AEOD activities include a broad-scope systematic review of operating experience, human performance studies, regulatory effectiveness studies, Senior Management Meeting support, reliability and risk assessment studies, evaluation of foreign events and advanced reporting system, and digital systems issues.
l
, The Honorable Shirley Jackson 5 Mr. Martin emphasized. that the AEOD programs constitute the essential independent review and assessment of power reactor and nuclear materials safety performance, and complement the reviews of operating events by the Regions, the Office of Nuclear Reactor Regulation, and the Office of Nuclear Material Safety and Safeguards. AEOD programs provide a quality verification function to assure feedback of important operational safety lessons. AEOD findings and recommendations continue to be addressed thrvugh generic correspondence, in the resolution of generic issues, and in initiatives taken by industry.
The Committee encouraged the continuation of AEOD independent reviews and j support to other NRC offices. The Committee also suggested that AEOD develop '
a strategy that encourages greater use of its studies.
]
Conclusion This briefing was for information only. No Committee action was required.
- 7. Dearaded Auxiliary Feedwater System Capability Durina a Rapid Downoower Event at Catawba Nuclear Power Plant. Unit 1 The Committee heard presentations by and held discussions with representatives of the NRC staff and Duke Power Company regarding the May 7,1998 incident, at the Catawba Nuclear Station Unit 1 involving degraded auxiliary feedwater system capability during a rapid downpower evolution. The Committee discussed the findings of the NRC Augmented inspection Team, safety implications of the event, and associated licensee actions.
Conclusion This briefing was for information only. No Committee action was required.
- 8. Prioritization of Generic Safety Issues The Committee held discussions with the representatives of the NRC staff on the priority rankings proposed by the staff for the tenth group of Generic Safety issues (GSIs). The Committee agreed with the rankings proposed by the staff for 17 of 21 GSis. The Committee also agreed with the staff's proposed priority rankings for the remaining GSis but provided some comments with the exception of issue 16,
" Seismically Induced Fires," of GSI-172, " Multiple System Responses Program."
I I
i 1
l l
l 1 . - The Honorable Shirley Jackson 6 Conclusion The Committee plans to provide a letter to the Executive Director'for Operations on this matter during the September 30-October 2,1998 ACRS meeting.
RECONCILIATION OF ACRS COMMENTS AND RECOMMENDATIONS The Committee discussed the responses from the NRC Executive Director for Operations (EDO) to ACRS comments and recommendations included in ACRS reports:
. The Committee discussed the EDO response dated August 27,1998, to ACRS comments and recommendations included in the ACRS report dated July 23,1998, concerning the safety aspects of the Westinghouse Electric Company application ,
for certification of the AP600 passive plant design. !
The Committee decided that it was satisfied with the EDO response related to the final design approval of the AP600, While reviewing the AP600 design, however, the Committee identified generic concerns that were not adequately addressed by the staff. The Committee plans to identify these concerns in a lessons learned letter l to the EDO.
l
. The Committee discussed the EDO response dated August 13,1998, to ACRS l comments and recommendations included in the ACRS letter dated July 21,1998, l concerning the proposed final safety evaluation of the BWR Vessel and Internals l Project, BWR pressure vessel shell weld inspection recommendations report, j The Committee decided that it was satisfied with the EDO's response. j i
. The Committee discussed the EDO response dated-August 3,1998, to ACRS l_ comments and recommendations included in the ACRS letter dated June 15,1998, concerning the safety aspects of the Westinghouse Electric Company application ;
for certification of the AP600 passive plant design, interim letter 3. l The Committee decided that it was satisfied with the EDO response related to the final design approval of the AP600. While reviewing the AP600 design, however, ,
the Committee identified generic concerns that were not adequately addressed by the staff. The Committee plans to identify these concerns in a letter to the EDO and to review related staff activities.
. The Committee discussed the EDO response dated July 31, 1998, to ACRS comments and recommendations included in the ACRS report dated June 12,1998, conceming the proposed final draft of the NRC Human Performance Plan.
.. =- j The Honorable Shirley Jackson 7 The Committee decided that it was satisfied with the EDO's response.
The Committee discussed the EDO response dated August 25,1998, to ACRS comments and recommendations included in the ACRS report dated July 20,1998, concerning Draft Supplement 1 to NUREG-1552," Fire Barrier Penetration Seals in NPPs." 4 l
The Committee decided that it was satisfied with the EDO's response.
l The Committee discussed the EDO response dated August 4,1998, to ACRS comments and recommendations included in the ACRS report dated June 16,1998, conceming SECY-98-076," Core Research Capabilities."
The Committee decided that it was satisfied with the EDO's response. However, the Committee plans to continue dialogue with the staff as further work and progress is made on core capability issues.
The Committee discussed the EDO response dated August 3,1998, to ACRS comments and recommendations included in the ACRS report dated March 13, 1998, concerning proposed improvements to the Senior Management Meeting i Process.
The Committee decided to continue its review of this matter during future meetings.
The Committee discussed the EDO response dated July 31, 1998, to ACRS comments and recommendations included in the ACRS report dated July 16,1998, concerning proposed revisions to 10 CFR 50.59 (Changes, tests and experiments).
The Committee decided to continue its review of this matter during future meetings.
The Committee discussed the EDO response dated July 24, 1998, to ACRS comments and recommendations included in the ACRS report dated June 15,1998, concerning the NRC Reactor Fuels Research Program.
The Committee decided that it was satisfied with the EDO's response. However, the Committee plans to continue dialogue with the staff on this matter during future meetings.
- The Committee discussed the EDO response dated July 20,1998, to ACRS comments and recommendations included in the ACRS report dated June 12,1998, concerning the Proposed Final Standard Review Plan Section 3.9.8 and Regulatory Guide 1.178 for risk-informed inservice inspection of piping.
1 The Honorable Shirley Jackson 8 The Committee decided that it was satisfied with the EDO's response.
OTHER RELATED ACTIVITIES OF THE COMMITTEE
- During the period from July 8,1998 through September 1,1998, the following Subcommit-tee meetings were held:
Plant License Renewal- July 16,1998 l
I The Subcommittee discussed the NRC staff's activities associated with license' renewal, proposed staff's plans, and schedule for reviewing the license renewal application and related safety issues. The Subcommittee also discussed the ACRS involvement in reviewing the license renewal submittal and related matters.
Safety Research Proaram - July 17,1998 The Subcommittee discussed the comments and recommendations included in the June 16,1998 ACRS report regarding Core Research Capabilities" and the associated response from the NRC Office of Nuclear Regulatory Research.
Plant Operations and Fire Protection - July 29,1998 The Subcommittees and Region 11 personnel discussed Region 11 stivities and l other items of mutual interest, including significant operating events, on-line l maintenance, the plant performance review program, results of the pilot fire i protection functional inspection, and other fire protection issues.
Reliability and Probabilistic Risk Assessment - August 26,1998 The Subcommittee discussed issues in the Staff Requirements Memorandum dated :
April 20,1998, regarding situation-specific cases where PRA results and insights !
have improved the existing regulatory system and specific areas in which PRA, when applied properly, can have a positive impact on the regulatory system. The Subcommittee also discussed staff and industry initiatives regarding these matters.
Thermal-Hydraulic Phenomena - August 27,1998 l The Subcommittee discussed the application by the Southern Nuclear Operating Company for a power level increase of 8% for the Edwin I. Hatch Nuclear Power Plant Units 1 and 2, pursuant to the General Electric Nuclear Energy extended power uprate program.
The Honorable Shirley Jackson 9
. Plannina and Procedures - September 1,1998 The Planning and Procedures Subcommittee discussed proposed ACRS activities, practices, and procedures for conducting Committee business and organizational and personnel matters relating to ACRS and its staff.
LIST OF FOLLOW-UP MATTERS FOR THE EXECUTIVE DIRECTOR FOR OPERATIONS E
l 1. The EDO responded on August '4,1998 to the ACRS letter of June 16,1998 L regarding SECY-98-076," Core Research Capabilities." The Committee plans to continue dialogue with the Office of Nuclear Regulatory Research staff as further work and progress is made on core capability issues.
- 2. The EDO responded on July 24, 1998 to the ACRS letter of June 15,1998 l regarding the NRC reactor fuels research program. The Committee plans to l l continue a dialogue with the NRC staff on this matter during future meetings.
, 3. The EDO responded on August 3,1998, to the ACRS report dated March 13,1998, I l concerning proposed improvements to the Senior Management Meeting Process.
The Committee plans to continue its review of this matter during future meetings. l
- 4. The EDO responded on July 31,1998, to the ACRS report dated July 16,1998, l l concerning proposed revisions to 10 CFR 50.59 (Changes, tests and experiments).
The Committee plans to continue its review of this matter during future meetings.
l 4
PROPOSED SCHEDULE FOR THE 456TH ACRS MEETING i
l The Committee agreed to consider the following during the 456th ACRS Meeting, September 30-October 2,1998:
l NEl Petition to Modifv 10 CFR 50.54(a) Related to Quality Assurance Proarams (Open) l The Committee will hear presentations by and hold discussions with representatives of the ;
l NRC staff and the Nuclear Energy Institute (NEI) regarding the NEl petition to modify 10 ;
l CFR 50.54(a) to negate the requirement for licensees to obtain NRC approval prior to ;
making changes to their quality assurance programs and the associated staff position.
Risk-Informed Pilot Apolication for Hydroaen Monitorina at Arkansas Nuclear One (Open) '
The Committee will hear presentations by and hold discussions with representatives of the NRC staff regarding a pilot application of a risk-informed approach for post-accident hydrogen monitoring at Arkansas Nuclear One. Representatives of the nuclear industry will provide their views, as appropriate.
I
.. .. 1
,- The Honorable Shirley Jackson 10 Performance Technoloav. Inc.. Views on Criteria for Safety Decisions (Open) The Committee will hear presentations by and hold discussions with representatives of Performance Technology, Inc., on criteria for safety decisions and comments on Regulatory Guide 1.174 (previously DG-1061).
Industry Initiatives to Certifv Probabilistic Risk Assessments (Open) The Committee will hear presentations by and hold discussions with representatives of the NRC staff and Owners' Groups, as appropriate, regarding industry initiatives to certify PRAs.
Lessons Learned from the Independent Safety Assessment of the Maine Yankee Atomic j Power Station and Associated Generic Safety Imolications (Open) The Committee will j hear presentations by and hold discussions with representatives of the NRC staff regarding the lessons learned from the independent safety assessment of the Maine Yankee Atomic Power Station and associated generic safety implications.
ACRS Reoorts to the Conaress and the Commission (Open) The Committee will discuss the 1999 ACRS report to Congress and the Commission on the NRC Safety Research Program: format and content, identification of issues, assignment of responsibilities, and schedule for providing input to the draft reports.
Intearated Review of Assessment Processes and Proposed imorovements to the Senior Manaaement Meetina Process (Open) The Committee will hear presentations by and hold discussions with representatives of the NRC staff regarding the status of activities associated with the integrated review of assessment processes and proposed improvements to the Senior Management Meeting Process.
Sincerely, R. L. Seale Chairman
!