ML20045F648
| ML20045F648 | |
| Person / Time | |
|---|---|
| Issue date: | 06/29/1993 |
| From: | Holahan G NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| To: | Gillespie F Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 9307080185 | |
| Download: ML20045F648 (3) | |
Text
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MEMORANDUM FOR:
Frank P. Gillespie, Director Program Management, Policy Development, and Analysis Staff Office of Nuclear Reactor Regulation FROM:
Gary M. Holahan, Director Division of Safety Programs Office for Analysis and Evaluation of Operational Data
SUBJECT:
REGULATORY REVIEW GROUP REPORT COMMENTS The Regulatory Review Group (RRG) undertook an extremely broad and difficult task, and provided a draft report with many interesting and thoughtful suggestions. However, we believe that the report needs some additional technical and editorial work, and further review by the staff before it would be ready for final publication.
P. Baranowsky discussed his comments directly with J. Murphy. We offer the following additional general and specific comments for your consideration.
General Comments
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Although the scope of the review was very broad, often the relationship of the analysis associated with the basis of the recommendation is not clear, and sometinies seems to be subjective, reflecting the Group's views, rather than on an evaluation of the safety and resource implications in question. Given the time and resource restrictions, it maybe that is all that could be reasonably expected. However, the limitations and uncertainties of such a subjective screening-type approach need to be recognized.
2.
It is important that the report be accurate regarding the need for plant specific versus generic data in implementing a risk-based regulatory framework. Currently, INP0 has under consideration a number of recommended changes to NPRDS which would include reporting of plant specific reliability and unavailability data for certain risk-important components.
INP0 has postponed making the decision on modifying NPRDS until the data needs for risk-based regulation have been formulated. The data needs which would be captured by the recommended changes would meet the identified needs of the NRC staff in NRR, RES, AE0D, as well as industry.
3.
The report does not appear to present a balanced picture of NRC requirements. There seems to be a presumption that there are mainly excessive regulation problems.
For example, in the area of shift staffing, the feeling is that by providing more than the Technical Specifications minimum requirements, licensees are incurring an unnecessary burden, and encourages reduction to the required minimum shift staffing level.
Recent AE0D studies on human performance and DET results indicate that the current NRC required 9307080185 930629 PDR REVGP NRCREOUL N
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minimum shift staffing levels may not be adequate.
Licensees may get the wrong message. The recommendation should be that each licensee should examine their own particular needs to safely operate their plant and that NRC should reexamine minimum shift staffing rcquirements in view of recent findings.
Likewise, Question H in the Regulatory Review Form - Regulations, on safe operation, seems to be biased in terms of assuming sufficient or excessive requirements.
Specific Comments 1.
In the Fire Protection Section (discussing Part 50.48 of NRC Regulations),
the RRG report should acknowledge NRR's re-assessment of the NRC fire protection program (February 1993) and follow-up actions.
It should be noted that in PRAs where external events have been considered, fire protection is an important safety issue, contributing 2 to 40 percent of the CDF. This would suggest a " substantial" safety rating on Question G of the Regulatory Review r
Form - Regulations.
Section 2.3.2, Commitments, notes that important issues should be included in license conditions. The report does not give a valid basis for the recommendation to remove fire protection from license conditions. (The referenced Section 2.3.5 should be 2.3.4).
2.
We agree with the need for a formal definition of " commitment." However, the suggested definition of " commitment" should not require that a written NRC document be present in the licensee's docket file to make it valid. At this time, it would be impractical to backfit the definition of " commitment" as stated in the RRG report, to 30 years of regulatory history.
3.
4he " Commitment"4 iscussion iSection 2.3.'2, page 9) states that the license amendment process allows changes where "the change to the commitment imust be proven by the licensee to be e%uivalent to the original comitment.",
sticense amendments need only meet the regulations and contain"'no undue risk."
Jhey do not need to perpetuate prior-comitments..e Also, we bel,ieve that the "f Lphrase "nust be proven,*gis Loo strong.,
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4.
The discussion on changes to commitments (Section 2.3.2, page 9) needs re-evaluation.
It sounds as though a process similar to 10 CFR 50.59 is suggested.
If 10 CFR 50.59 is applicable, it should be used.
If it is not applicable, the licensee can make changes it considers appropriate to deal with the safety issue in question.
5.
The report encourages increased use of risk based and performance based regulations. We are supportive of an integral plan to cover research, development, implementation and use of PRA-based techniques. However, the report does not acknowledge that these approaches require information not currently available. The reporting requirements section should identify the need for reliability data to support risk based decisions. At present, PRA could be used if the analysis is not too dependent on numbers. This would be especially true in the application of 10 CFR 50.59.
6.
In Volume 4, page 4-4, there is a statement, "In effect, the NRC currently uses PRA insights to primarily add requirements to the industry." Although PRA is an excellent tool to identify the weak points in a chain, PRA insights are also used, and in fact, often direct the staff away from new requirements, (e.g., CRGR, Generic issue prioritization and resolution).
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Frank P. Gillespie.
7.
The report recommends that the utilization of PRA-based techniques in the regulatory process be characterized into three general classes (Volume 4, page 4-1 and 4-2).
The first two of the three general classes are called
" Quantitative," when in fact appear to be more " Qualitative" in their approach. The discussion should also include importance measures and qualitative insights.
8.
The statements regarding appropriate use of plant specific data versus generic data in PRAs are not always clear.
In pages 4-16 to 4-19, the material regarding data is clear and unambiguous that plant specific data are preferred, but generic data may be used if plant specific data are not available. It also cautions that the use of generic data in a PRA places limitation on the application of the PRA within the regulatory framework.
However, the material on page 4-33 addressing data is not very clear. The material about data on page 4-40 does not seem to be consistent with previous statements.
9.
In page 4-39, the discussion of the configuration application regarding STIs does not provide specifics on how to treat the identified complexities, (e.g., time-dependent failure rate, demand stresses), in the calculation of unavailability, and the effect of not doing so.
Please call me (492-4484) if you want to discuss these comments.
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Gary M. Holahan, Director Division of Safety Programs Office for Analysis and Evaluation of Operational Data CC:
E. Jordan D. Ross J. Rosenthal P. Baranoswky V. Benaroya J. Murphy c
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