ML20004B162
| ML20004B162 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 05/21/1981 |
| From: | Lindsay W FEDERAL ENERGY REGULATORY COMMISSION |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8105270319 | |
| Download: ML20004B162 (2) | |
Text
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FEDERAL ENERGY REGULATORY COMMISSION WASHINGTON 2@426 IN REPLY REFER To:
Mr. Dennis M. Crutchfield
,-ga, go Chief, Operating Reactors Branch #5 MAy 211981 3 Division of Licensing f
U.S. Nuclear Regulatory Commission 27 j
1717 H Street, NW.
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i Washington, D.C.
20555
Dear Mr. Crutchfield:
kl This is in response to your April 6, 1981 letter to Mr. Haray. Thomas,\\y f' requesting a review of two enclosed reports on flood potentiif'c4l56 F of the Upper Deerfield River and the impact of Harriman and Sherman dams failure on the NRC licensed Yankee Rowe Nuclear Power Station.
The Harriman and Sherman dans studied in the reports are licensed to New England Power Company under FERC No. 2323 One of the reports was prepared by the NRC and the other by the Yankee Atomic Electric Company.
Each report analyzed the flood potential of the Upper Deerfield River above the Sherman Dam, which forms the reservoir used as a cooling water source for the nuclear station.
Each report used a different approach for developing the estimated probable maxumum flood at the dans and each report reached different conclusions.
The NRC report critiqued the Yankee Atomic report; however, Yankee Atomic was apparently not given the opportunity to respor.d.
We would be interested in either a response or a critique of the NRC report by Yankee Atomic.
The NRC report is consistent with current concepts and techniques for developing probable maximum floods.
Table 5.1 of the NRC report shows that for PMF's developed by C. T. Main, NRC, and the USCE the Harrin.an and Sherman Dams would probably fail. NRC estimates a significantly higher outflow from the dam breach than C. T. Main as shown on Table 5.1.
l C. T. Main was the independen* consultant retained by New England Power Company to do the 1973 Part 12 Safety Evaluation i
l for Project No. 2323 The consultant's predicted outflow from a dam breach does noc appear to be consistent with the outflow which would be predicted using state-of-the-art technology.
The next safety inspection report for the Deerfield River l
Dans is due in 1983 We will require the Licensee to reassess l
the effects of probable maximum flood flows on Harriman and Sherman Dams and the results of any failure due to overtopping using state-of-the-art criteria.
The licensee will be Coo 2 s
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required to assess the risk of Harriman and Sherman Dam failures on downstream life and property, with consideration of the impact on the Rowe Nuclear Plant and, if the. risk
unacceptable, will be required to make such modifications to the project as may be necessary to insure the safety of the dams under PMF conditions.
As part of the FERC dams safety program, Licensees owning hydraulic fill dams are being required to provide dynamic stability analyses of the dams using current analytic techniques and the maximum credible earthquake.
Therefore, the Licensee will also be required to include in its report such analyses or the results of such analyses for Harriman and Sherman Dams.
A copy of this letter is being forwarded to New England Power Company to provide advance notice of the special requirements for the 1983 Safety Evaluation Report for Project No. 2323 It is hoped the above satisfactorily addresses the concerns of the Nuclear Regulatory Commission.
If you have any questions regarding these matters please. call Mr. Harry Thomas Chief, Inspections Branch or Mr. Gerald Wilson, Chief, Project Analysis Branch.
Sincerely,
- m William W. Lindsay
)
Director, Office of Ele 6tric Power Regulation
.