ML25196A177
| ML25196A177 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 02/17/1977 |
| From: | Fraley R Advisory Committee on Reactor Safeguards |
| To: | Rusche B Office of Nuclear Reactor Regulation |
| References | |
| Download: ML25196A177 (1) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION ADVISORY COMMITTEE ON REACTOR SAFEGUARDS WASHINGTON, D. C. 20555 February 17, 1977 Benard C. Rusche, Director Office of Nuclear Reactor Regulation
SUBJECT:
ACRS REPORI' ON D.l\VIS-BESSE NUCLEAR POiER STATION, UNIT 1, DATED JANUARY 14, 1977 During the 202nd ACRS meeting, the Committee considered your request of January 31, 1977 for clarification of the subject ACRS report.
The members discussed the bases for the Committee's report on the Davis-Besse Station and the comments noted below are reflected in the meeting minutes.
The NRC Staff interpretation of the first matter, as it appears in the last 5 lines on page 2 and the first 5 lines of page 3 is correct except in the following respects:
(a)
In the Committee's opinion "currently accepted procedures for de~onvolution" are not acceptable at this site for structures founded on rock. It is the Corrmittee's opinion that the Regulatory Guide 1.60 Design Response Spectra should be applied at the foundation level of such structures.
(b)
The systems to be investigated should include those needed for continued shutdown heat removal as well as those "systems needed for safe shutdown."
(c)
In view of the fact that the review is being made for a plant designed to different criteria, and already constructed, the responses of the components and systems reviewed need not be strictly "within current acceptance limits." Instances in which those limits are exceeded may be considered acceptable on a judgment basis, with due consideration to the contribution of seismic :rrotions to the overall response.
The second matter, surrnnarized on page 3 of your letter was intended to address the generic item "Instrrnnentation to Follow the Course of an Accident" (Item II-11 of the ACRS report on Generic Items dated April 16, 1976) with the following clarification:
(a)
Appropriate emphasis should be given to the resolution of this item so that it is accomplished prior to comnercial operation of the Davis-Besse 1 Plant.
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February 17, 1977 (b)
Additional attention should be given to develo?nent of proce-dures to be used by the plant operators in taking appropriate corrective action for incidents and accidents with very low probabilities of occurrence.
'!be Corrmittee plans to give further attention to the developnent of procedures to cope with operating events of intermediate probability to limit their consequences on the public health and safety. 'Ibis will be done on a generic basis, however.
cc:
L. Gossick, EDO S. Olilk, Secy.
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Execut1~:1;lrec~r 332