ML20202G257
| ML20202G257 | |
| Person / Time | |
|---|---|
| Site: | Mcguire |
| Issue date: | 04/08/1986 |
| From: | Tien Cl CALIFORNIA, UNIV. OF, BERKELEY, CA, Advisory Committee on Reactor Safeguards |
| To: | Boehnert P Advisory Committee on Reactor Safeguards |
| References | |
| ACRS-CT-1842, NUDOCS 8607150351 | |
| Download: ML20202G257 (2) | |
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UNIVERSITY OF CALIFORNIA, BERKELEY
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- IRVINE
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u COLLECE OF ENGINEERING BERKELEY, CALIFORNIA 94720 MECIIANICAL ENGINEERING April 8,1986 I
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Mr. Paul A. Boehnert ACRS Nuclear Regulatory Commission Washington, DC 20555
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RE: ACRS Combined DHRS/ECCS Subcommittee Meeting, March 26, 1986, Washington,11C
Dear Paul:
This constitutes my report on the above-referenced one-day meeting which mainly reviewed the Duke Power Company request to delete / disable the ECCS UHI system at McGuire, Unit 2.
Near the end of the meeting, about one-hour time was spent on the preliminary discussion of the proposed NRR resolution position for Generic Issue 124 " Auxiliary Feedwater System Reliability." Having missed all i
the previous meetings on the request of UHI deletion and disabling, I am not particularly familiar with all the background and sensitive issues involved. My.
brief comments below must be viewed in this light.
I have no comments on the GI-124 presentation because of its preliminary nature and my lack of prior par-ticipation in the DHRS subcommittee meetings.
UHI Deletion / Disabling at McGuire, Unit 2 1.
The presentations were poorly prepared and confusing. Apparently, the preparation of the materials was greatly rushed by the set deadline on the conpletion of this review by April 14, 1986.
2.
For evidence to support the request, many computations were performed and presented, including the calculations from the Westinghouse BART code (not to mention the earlier BASH code) and the TRAC code for various cases of with/without UHI, different FR values, etc. Disappointingly, however, there was no direct, systematic comparison of the calculated results on a common basis.
3.
Despite the poor presentation and incomplete evidence from code calcu-lations, it appears that UHI deletion / disabling would not have any appreciable adverse effect and would be still in compliance with Appendix K requirements.
It should be reco'gnized, however, that the B-E and E-M calculations may not reflect the true safety margins in the real world.
@ ljo351 860408 CT-1s4 HRS Dr3IGI!ATED ORIGIl!AL
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_2-It seems that the strongest argument for UHI deletion / disabling still 4.
comes from plant operational aspects, i.e., to eliminate or reduce the opera-tional nuisance caused by UHI in refueling, piping, etc.
Sincerely yours, s
k Cha -Lin Tien Pr essor CLT:SB i
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