ML20133K542
| ML20133K542 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 10/15/1985 |
| From: | Heider L YANKEE ATOMIC ELECTRIC CO. |
| To: | Thompson H Office of Nuclear Reactor Regulation |
| References | |
| FYR-85-107, GL-85-06, GL-85-6, NUDOCS 8510220140 | |
| Download: ML20133K542 (11) | |
Text
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YANKEE ATOMIC ELECTRIC COMPANY Tc*ho"c(6")*'**'
- TWX 710 380 7619
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1671 Worcester Road, Framingharn Massachusetts 01701 2.C.2.1 l
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FYR 85-107
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October 15, 1985 Director of Nuclear Roactor Regulation United States Nuclear Regulatory Commission Washington, DC 20555 Attention:
Mr. Hugh L. Thompson, Jr.
Director, Division of Licensing
References:
(a) License No. DPR-3 (Docket No. 50-29)
(b) USNRC Letter to All Power Reactor Licensees, dated April 16, 1985 (Generic Letter 85-06)
(c) 10CFR, Part 50.62, " Reduction of Risk From Anticipated Transients Without Scram (ATWS) Events for Light-Water-Cooled Nuclear Power Plants " Final Rule 49FR26036 (d) Yankee Nuclear Power Station Probabilistic Safety Study (e) USNRC Letter to YAEC, dated August 16, 1982 (f) NUREG-0825, June 1983 (g) AEOD/P405, " Final Trends and Patterns Report on Feedwater Transients at Westinghouse Plants"
Subject:
Request. for Exemption from the ATWS Rule
Dear Sir:
We have reviewed Generic Letter 85-06, Reference (b), on the implementation of the ATWS rule and rotated guidance provided in the Federal Register, Reference (c), for the Yankoo Nuclear Power Station (YNPS). The Federal Register states that exempt.Lons to the ATWS rule may be granted to plants licensed to operate prior to August 1969 if it can be demonstrated that their risk from ATWS is sufficiently low due to such factors as power level, unique design features, remaining plant lifetime and remote siting. After careful consideration of the rule, we conclude that the risk of an ATWS at YNPS is sufficiently low and request an exemption from the rule. Our request is based on the sua11 size and remote siting of YNPS, unique features associated with its Reactor Trip System, the experience and training of the operators and the excellent operating record over the past 25 years.
YNPS is a Westinghouse, four-loop, Pressurized Water Reactor (PWR) and is relatively small by today's standards. The electrical output is 185 MWe versus 1,200 MWe; the core is 7.5 feet high versus 12 feet; the core diameter is 6.3 feet versus 11 feet, there are 76 fuel assemblies versus bdl# [5 193 assemblies; and the core thermal output is 600 MW versus 3,400 MW.
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