ML19276F268
| ML19276F268 | |
| Person / Time | |
|---|---|
| Issue date: | 03/05/1979 |
| From: | Hendrie J NRC COMMISSION (OCM) |
| To: | Day G ILLINOIS, STATE OF |
| Shared Package | |
| ML19276F269 | List: |
| References | |
| NUDOCS 7903280168 | |
| Download: ML19276F268 (7) | |
Text
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March 5, 1979 CHAIRMAN Mr. Gerald R. Day Executive Director Illinois Commission on Atomic Energy 110 East Adams Street Springfield,' Illinois 62706
Dear Mr. Day:
This responds to your letter of February 2,1979, concerning release of the Comission's policy statement on the Reactor Safety Study (WASH-1400) and the review of that study by the Risk Assessment Review Group headed by Dr. Harold Lewis.
I am pleased to provide the infor-mation you requested.
You commented that you believe there were considerable differences between the NRC press release--which included the text of the Comission policy statement--and the content of the report of the Risk Assessment Review Group.
I believe a careful reading of both documents, together with the tran-script of the Review Group's briefing of the Commission on September 7, 1978, would show that this is not the case.
While there are, as you point out, a number of positive statements concerning WASH 1400 in the Review Group Report, there also were a number of criticisins.
The Commission's policy statement and press release discussed those matters.
Both documents noted the praise by the review group of the Safety Study's general methodology, its contribution to assessing the risks of nuclear power and the recommendations on future use of probabilistic risk assessment in the regulatory process.
The criticisms of the Review Group also were outlined, as were the Commission's conclusions on those matters.
You also asked about the development of the Commission policy statement and the press release.
The policy statement was approved unanimously by the Comission and the Comissioners also reviewed the press release.
In retrospect, I believe we may not have given sufficient notice that this statement was imminent.
We probably should have given some noti-fication to allow both the news media and interested organizations more time to study the matter carefully.
7 90 3 28 01G8
Mr. Gerald R. Day ;
I am enclosing an excerpt from my February 5, 1979, testimony before the Senate Ccmmittee on Environment and Public Works which discusses the Satety Study, the Risk Assessment Review Group Report and the Commission's policy statement, and their relationship to the health and safety regulatory system for nuclear power plants.
I hope you will find this information helpful.
- , Sincerely, t
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'JoTeph M. Hendrie
Enclosure:
As stated I
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Budget - 7 Excerpt from Chairman Hendrie's 2/5/79 testimony
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The Risk Assessment Review Group Report As you know, the NRC established the Risk Assessment Review Group in July 1977, under the leadership of Dr. Harold Lewis, Chairman of the American Physical Society's Study Group on Light Nater Reactors, with four elements to its charter:
clarify the achievements and limitations of WASH-1400;
-- assess the peer comments thereon, and responses to these comments;
-- study the present state of risk assessment methodology;
-- recommend to the Commission how (and whether) such methodology can be used in the regulatory and licensing process, t
's 11e Review Group published its report last September, and it was
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provided to the Congress at that time.
'i After consideration of the Review Group's findings, the Commission.
issued a policy statement on January 18th summarizing its response to the Report.
In the Statement, the Commission accepted the Report's findings and noted its actions as follows, and I quote:
" Executive Summary:
The Commission withdraws any explicit or implicit past endorsement of the Executive Summary.
'The Peer Review Process: The Commission agrees that the peer review process followed in publishing NASH-1400 was inadequate and that proper peer review is fundamental to making sound technical decisions.
The Commissicn will take whatever corrective action is necessary to assure that effective peer review is an.incegral feature of the NRC's risk assessment program.
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" Accident Probabilities:
The Commission accepts the Review Group Report's conclusion that absolute values of the risks presented should not be used uncritically either in the regulatory process or for public policy purposes and has taken and will continue to take steps to assure that any such use in the past will be corrected as appropriate.
In particular, in light of the Review Group conclusions on accident probabilities, the Commission does not regard as reliable the Reactor Safety Study's numerical estimate of the overall risk of reactor accident.
" Communication with the Congress and the Public:
Canmissioner correspondence and statements involving WASH-1400 are being reviewed and corrective 5
action as necessary will be taken."
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'liith respect to the component parts of the Reactor Safety Study
, the-Commission expects the staff to make use of them as appropriate, that is, where the data base is adequate and analytical techniques perndt.
Taking dee account of the reservations expressed in the Review Group Report, and in its presentation to the Commission, the Commission supports the extended use of probabilistic risk assessment in regulatory decision The Commission has provided additional detailed instructions to the NRC staff concerning continued use of risk assessment techniques and results in response to the specific comments of the Risk Assessment Review Grou and has asked the staff to submit by June 30, 1979, detailed procedures to ensure the proper and effective use of risk assessment theory, methods, data development, and statistical analyses.
Budget - 8a INSERT TO PREPARED TESTIFDNY OF JOSEPli M. HENDRIE; TO BE INSERTED AITER P. 8 I would note that a primary goal of the Reactor Safety Study, as s
established in 1972, was to obtain a'" quantitative evaluation of the risk from the operation of a nuclear plant." 'lhe Safety Study was, in effect, a " measurement," made by analyzing two typical plant designs, of the effectiveness of an existing system of nuclear regulation.
That regulatory system depends on having nuclear plants sited, designed, constructed, and operated on the basis of conservative applica-tion of sound and accepted engineering principles, on req'uirements for multiple and redundant safety systems, and on a set of regulatory requirements that are updated to reflect operating experience. The de. signers, builders, and operators of these plants are required to have l
i-effective quality assurance ' programs and their iork is subjected to a continuing licensing and inspection process by the UF.C.
The results of the licensing and inspection process are, in turn, subject to independent review by the Advisory Committee on Reactor Safeguards and often to examination in public hearings.
'Ihis. health and safety regulatory system, much of which evolved long before the Reactor Safety Study was carried out, is unchanged in I
its basic principles today.
It does not depend on the ability to make precise quantitative estimates of overall risk -- although that ability would be highly useful and should be developed..
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Eudget - Sb s
Ne believe this regulatory system has served us well.
It is an exceptionally rigorous system, and appropriately so in view of the technology we regulate.
It is our job as regulators to make sure that' there is no undue risk from licensed facilities and, while one must acknowledge strongly held views to the contrary, over 400 reactor-years of experie'nce to date give us reason to believe that we are on the right track.
hhat the Lewis group has told us is that the " measurement" of our regulatory system, as reflected in the overall risk estimates of the Reactor Safety Study, is much less precise than had been asserted. The Lewis group did not conclude that the overall risk estimates were higher or lower than reported in WASH-1400, although they speculated on possible factors in both directions, but only that they thought the error bands en those estimates were substantially larger than had been reported.
On that account, they recommended to us that the overall risk estimates of
'G.SH-1400 should be used with great' caution - "should not be used uncritically" were their words -- in the regulatory procer.s or for-public policy purposes. We have accepted and are implementing with, vigor that recommendation, as well as the other findings and recommenda-tiens of the Lewis group. We are also carefully reviewing past regulatory decisions to ascertain whether actions contrary to those.
recomendations have been taken.
Budget - 8c s
To sum up, it is important to keep in mind what the Commission did and did not do in response to the Lewis Report.
It did reevaluate its reliance on, and relationship to, the Reactor Safety Study.
However, it did not thereby take a new view of reactor safety.
Nor did the Comission.
take a new view of past licensing decisions that each licensed plant I
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will be so operated as to provide adequate protection to the health and safety of the public.
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