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UNITED STATES Mi o
NUCLEAR REGULATORY COMMISSION s,
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JAN 151992
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u Mr. David A. Ward,' Chairman -
Advisory Committee on Reactor Safeguards U.S. Nuclear Regulatory Commission L
Washington, DC 20555
Dear Mr. Ward:
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The December 18, 1991, ACRS commented on'the proposed staff procedure to account for the safety goal policy in considering new regulatory initiatives-t highlighted, as areas.of not fulfilling Commission wishes, that the staff-procedure did not incorporate the concept of'a threshold defining "how safe is i
safe enough" and it uses cost-benefit analysis to' decide whether -
i implementation of a proposed 'nitiative-is warranted.-
j On the first point, the staff agrees that a definition of. "how safe is safe i
enough" is not in the procedure, and the reasons for this were not clearly discussed in the Commission paper (SECY 91-270). The staff believes that Commission guidance allowed a graded approach to safety goal implementation, 1.e., situations where staff action is needed, situations where staff action may or may not be needed, and situations.where no further staff action is warranted. The staff procedure attempts to recognize'and account for two l
factors. First, PRA results are often highly uncertain ir.--terms of absolute i
values, and far more confidence can be placed in calculating a change.in risk using consistent methodology, assumptions and data.
Secondly, the staff chose i
to. express changes in risk in-terms of benchmarks.
Staff believes that'the use of such benchmarks will achieve safcty improvements consistent with the safety goals while at the same time provide a useful measure for applying the j
" substantial increase in overall protection" criterion in the backfit rule.
l With regards to cost-benefit analysis, including the value ~ ascribed to averted i
health effects-($1000 per person-rem),-the staff did not intend to imply that
.l this cost-benefit test was part of the safety goals.. Cost-benefit-analysis is an integral part of the regulatory analysis routinely developed for all new initiatives. The-staff's-procedure simply introduces a decision point based on safety goal considerations on whether or. not it is necessary or appropriate to proceed with completing the regulatory analysis; i.e., to proceed with conducting the cost-benefit analysis.
i The Committee also noted the desirability of developing a plan for reviewing existing regulations against the safety goal policy.
The staff has been requested by the Commission to develop such a plan, but believes that it would be best to obtain general agreement on the approach for assessing new initiatives from a safety goal perspective before considering a review of i
existing regulations, a process which would be very resource intensive.
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9408170094 940629 bORRESP f
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l Mr. David A. Ward 2
3 The staff supports the Committee undertaking the development of an alternative implementation plan.
If such an effort is undertaken, we stand ready to help.
We also believe it would be useful for the staff to continue its dialogue with t-the Committee on safety goal considerations, and look forward to future meetings on this subject.
Sincerely, i
foJmesM. Taylor ecutive Director for Operations cc:
The Chairman Comraissioner Rogers I. -Gemmissioner Curtiss Commissioner Remick Commissioner de Planque SECY I
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