ML19347B649
| ML19347B649 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 10/08/1980 |
| From: | Linder F DAIRYLAND POWER COOPERATIVE |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| LAC-7177, NUDOCS 8010150496 | |
| Download: ML19347B649 (1) | |
Text
_
D DA/RYLAND
[_S/b[M[COOPERA T/VE "o so< w aum w <.oum t 4 a>ozr e. so:m wm i
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October 8, 1980 In reply, please refer to LAC-7177 DOCKET NO. 50-409 Director of Nuclear Reactor Regulation ATTN:
Mr. Dennis M.
Crutchfield Operating Reactors Branch # 5 Division of Operating Reactors U.
S.
Nuclear Regulatory Commission Washington, D.
C.
20555
SUBJECT:
DAIRYLAND POWER COOPERATIVE LA CROSSE BOILING WATER REACTOR (LAr BFR)
]
PROVISIONAL OPERATING LICENSE NO. D?R-45 SYSTEMATIC EVALUATION PROGRAM TOPIC VIII ELECTRICAL PENETRATIONS OF REACTOR CONTAINMENT
Reference:
(1)
NRC Letter, Crutchfield to Linder, dated July 1, 1980.
Gentlenen:
In response to your letter (Reference 1), we believe the evaluation performed by the NRC for the LACBWR electrical penetrations assumes failure of the penetration when the penetration conductor exceeds a temperature equal to that at which the epoxy seal used at the end of J
each penetration cable softens.
In the LACBWR penetration design, the epoxy seals are not required for the penetration to function.
The epoxy seals are used to prevent moisture from entering the penetration cables.
With the epoxy seal removed, penetration integrity is maintained by the penetration cable insulating material.
This material, magnesium oxide, has a melting temperature significantly greater than copper and is insoluble'in water.. Also, due to their short length and relatively large wire size, leads from the penetration are self-supporting and do not require the presence of the epoxy seal
[
to maintain physical separation.
If you have any questions agarding this submittal, please contact us.
t Very truly yours, I
DAIRYLAND POWE COOPERATIVE j\\
W[1: B -t t-rLf/
% h; Frank Linder, General Manager FL:WRN:af cc:
J. G.
Keppler, Reg. Dir., NRC-DRO III ko 4
NRC Resident Inspectors j
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