ML20136E232
| ML20136E232 | |
| Person / Time | |
|---|---|
| Issue date: | 11/14/1985 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | Advisory Committee on Reactor Safeguards |
| References | |
| REF-GTECI-A-17, REF-GTECI-SY, TASK-A-17, TASK-OR ACRS-2373, NUDOCS 8601060472 | |
| Download: ML20136E232 (5) | |
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4 DATE ISSUED: 11/14/85 ACRS MEETING MINUTES ON THE SAFETY PHILOSOPHY TECHNOLOGY, AND CRITERIA SUBCOMMITTEE N
NOVEMBER 6, 1985 WASHINGTON, DC Purpose The ACRS Subcommittee on Safety Philosophy, Technology and Criteria met on November 6, 1985 at 1717 H Street, N.W., Washington, D.C.
The purpose of this meeting was to continue the discussions on the ED0's development of recommendations for revising the 1983 Safety Goal Policy and NRC's future use of.a Safety Goal Policy, the status of the NRC work on' the resolution of USI A-17 (" System Interactions in Nuclear Power Plants"), and the status of the NRC Staff's work on steam generator overfill. A Subcommittee report was planned for the November 7-9, 1985 ACRS meeting. The Subcommittee heard presentations from the EDO, NRR, and INEL. The meeting begin at 1:00 pm and adjourned at approximately 6:00 pm. The principle attendees were as follows:
ACRS D. Okrent, Subcomittee Chairman C. Michelson, Member F. Remick, Member R. Savio, ACRS Staff NRC V. Stello, ED0 M. Taylor, ED0 J. Sniezek, E00 N. Anderson, NRR K. Shaukat, NRR H.Magleby,NRRConsultant(INEL) 860106o4 c-3 cectstica3,_6/m
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SPT&C Meeting Minutes November 6, 1985 Highlights 1.
Mr. Stello summarized the EDO current proposal for implementing a safety goal policy. The proposed revised policy elevates the core melt frequency design objective to a " primary" goal and proposes the following set of cost / benefit guidelines:
Estimated Cost / Benefit Guideline to be used Core Melt (A0SC => averted on-site costs)
Frequency *
(large-scale core melt Meets the Individual Does not meet one perry) and Societal Goals or both of the Individual or Societal Goals
- mean value
( 10-5 No improvements Use $1000/P-R required 10-5 to 10-4
$1000/P-R +
$1000/P-R + AOSC 1% to 0% of.AOSC 10-4 to 10-3
$1000/P-R +
$1000/P-R + A0SC 10% to 1% of AOSC
) 10-3
$1000/P-R + AOSC Fix without regard to costs There was some discussion as to if it is within the scope of the NRC's authority to consider averted on-site costs in the cost /
benefit guidelines. Mr. Stello indicated that he had been advised by the NRC's lawyers'that it was and was expecting a paper from I
them giving the. basis for this opinion. Mr. Stello stated that he 4
I SPT&C Meeting Minutes November 6, 1985 believed that future plants should be-required to be in the "
10-5" and " Meets the Individual and Societial Goal" category.
2.
There was some discussion as to what issues were not addressed or resolved within the proposed Safety Goal Policy. These were as follows:
There is still some controversy as to the inclusion of averted on-site costs within the cost / benefit guideline.
The time-scale on which required fixes should be implemented is not addressed.
- The treatment of uncertainty in measuring compliance with a safety goal is still not addressed. There is a Staff rec-ommendatic.1 for displaying uncertainty but no guidance as to how it should be considered in the decision process.
The NRC Staff is presently developing containment performance design objectives. This concept is contained in the present safety goal policy only to the extent that it is done indi-rectly on the prompt fatality (Individual Goal) and latent cancer (Societal Goal) quantitative limits.
- The current Safety Goal Policy does not contain a true soci-etal quantitative safety goal. The prompt fatality and latent cancer quantitative limits only count population near the plant site, i
- Specific guidelines for future plants are not included in the current Safety Goel Policy.
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f SPT&C Meeting Minutes November 6, 1985 i
- This is still ' debate as to the distances to be used in comput-ing the prompt fatality and latent cancers limits. The distances under discussion range from 50 miles to 1 mile with the attendant differences in exposed population.
Proposals have been made to limit the risk contribution of the individual accident scenarios to some fraction of the total
. safety goal, with 10% having been frequently recomended. The current policy does not address this issue.
- The relation of the backfitting guidelines proposed in the safety goal policy to the Backfit' Rule and Severe Accident Policy has not been resolved.
3.
Mr. Anderson and Mr. Thacker sumarized the status of the work on USI A-17. The technical work has been completed and a draft CRGR document package has been circulated for NRC Staff review. Com-ments are now being received and evaluated. An effort is currently underway to make the proposed work more effective by incorporating into other existing programs.
It is expected that a revised NRC Staff proposal will be available for Subcommittee review in early January.
4.
Mr. Anderson and Mr. Magleby sumarized water hamer studies being conducted at INEL in support of the steam generator overfill programs. The work involves computation of the dynamic loads associated with potential water hamer events as identified in the steam generator overfill program. Steam generator level control failure at power (H. B. Robinson), f ailure of feedwater pumps to trip following a turbine trip (0conee-1), and a double-ended rupture of a steam generator tube with failure of feedwater pumps totrip(CalvertCliffs)wereconsidered. Preliminary calculations indicate that the loads (and possible consequences) would be
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SPT&C Meeting Minutes November 6, 1985 significant. Efforts are now being made to improve calculational models and more adequately assess the implications.
NOTE:
Additional meeting details can be obtained from a transcript of this meeting available in the NRC Public Document Room, 1717 H Street, N.W., Washington, D.C., or can be purchased 1
from ACE-Federal Reports, 444 North Capitol Street, Washing-ton, D.C. 20001, (202) 347-3700, i
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