ML20004B007
| ML20004B007 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 05/18/1981 |
| From: | Garrity J Maine Yankee |
| To: | Eisenhut D Office of Nuclear Reactor Regulation |
| References | |
| FMY-81-77, JHG-81-143, NUDOCS 8105270100 | |
| Download: ML20004B007 (1) | |
Text
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O May 18, 1981 FMY 81-77 8
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thited States tuclear Regulatory Commission t
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l Washington, D. C.
20555 f v.s, &, _,
l 1
l Attention:
Mr. Darrell G. Eisenhu;, Director p'
g Division of Licensing
&y 1
s
Reference:
(a) License tc. DPR-36 (Docket to. 50-309)
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(b) USTRC Letter, D. G. Eisenhut to all Licensees of Operating FWR FOclear Power Plants dated April 20, 1981 i
Dear Sir:
Reference (b) requested Maine Yankee Atomic Power Company to provide a docketed response identifying specific actions proposed to resolve concerns regarding thermal shock to reactor pressure vessels from overcooling transients.
These concerns were the subject of meetings between the NRC staff and industry respresentatives on March 31 and April 29, 1981. During these I
meetings representatives of the PWR Owners' Groups committed to submitting t
l latter reports by May 15, 1981 summarizing individual Owners' Group efforts to date. Enclosure 1 provides a copy of the Combustion Engineering Owners' Group i
(CEOG) letter report including a summary of proposed activities.
Maine Yankee is a participant in the Comoustko Engineering Owners' Group and i
is reviewing the proposed activites outlined in Enclosure 1.
Although the activities appear satisfactory and we expect to participate in the program l
described therein, Maine Yankee cannot fully commit to participation until a commercial proposal has been received from Comoustion Engineering and evaluated. Shculd upon evaluation of the commercial proposal Maine Yankee decide to pursue an alternate, you will be notifiec immediately.
Very truly yours, MAINE YAtKEE ATOMIC POWER COMPANY i
John H. Garrity, 01 rector l
Nuclear Engineering and Licensing l
CHG/plb 8105270100' f
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Southern California Edison Company CE P. O BOX 800 2 2 44 W ALNUT GROVE AVENU E ROSEM E AD. C AU FORNI A 91770 K. P. B ASKtN vggae omg
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Mr. Darrell G. Eisenhut, Director Division of Licensing Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D.C.
20555
Dear Mr. Eisenhut:
Subject:
Reactor Vessel Pressurized Thermal Shock
References:
(A)
NRC Memorandum frum T. J. Walker to S. S. Pawlicki, April 9,1981, " Minutes of PWR Owners' Group Meeting with NRC on March 31, 1981" (B) C-E Letter from W. R. Corcoran to F. Schroeder, dated June 24, 1975, LD-75-431 This letter fulfills a connitment made by the C-E Owners Group in response to your request at a meeting on March 31, 1981, (Ref. A) and responds to further requests and clarifications which you provided at a meeting on April 29, 1981, concerning the issue of reactor vessel pressurized thermal shock.
,This letter addresses three general aspects of the reactor vessel pressurized thermal shock issue. The letter provides a brief summary of previous analyses of the integrity of reactor vessels in C-E designed nuclear steam supply systems (NSSS) which confirm that there is sufficient safety margin to allow continued operation of these plants.
The letter contains a description of further programs which are currently being reviewed by the C-E Owners Group to develop further measures to assure continued reactor vessel integrity and hence safe plant operation. We understand a general description of an industry program to assure reactor vessel integrity is being prepared by the Electric Power Research Institutin and will be forwardec at a later date.
ASSURAtiCE OF VESSEL INTEGRITY
' ior to the March 31, 1981 meeting, the C-E Owners Group had not as a group
.-participated in any activities involving the evaluation of reactor vessel integrity during overcooling /repressurization transients which are initiated in the secondary system. The C-E Owners Group had previously authorized Combustion Engineering (C-E) to develop a program for the purpose of Y
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