ML20209F161

Requests Response to 860828 Memo to Chairman Zech Re Johnson Concern About Earthquake Near Plant

ML20209F161
Person / Time
Site:	Perry
Issue date:	09/08/1986
From:	Asselstine J NRC COMMISSION (OCM)
To:	Stello V NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
Shared Package
ML20209F127	List: ML20209F123 ML20209F161
References
OL, NUDOCS 8609120065
Download: ML20209F161 (1)

Text

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h UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555 g

% September 8,1986 OFFICE OF THE COMMISSIONER MEMORANDUM FOR: Victor Stello, Jr.

Executive Director for Operations FROM: James K. Asselstine---

SUBJECT:

STAFF RESPONSE TO JOHNSON CONCERN E PERRY E THQUAKE Because of time constraints during the September 5,1986 Comission meeting on Perry I was unable to raise several questions regarding the August 28, 1986 memorandum to Chairman Zech on the above indicated subject. I would appreciate receiving responses to the following:

1. To what extent would the 1986 Ohio earthquake influence the design or staff review of a new application for a plant proposed to be built in ..

Ohio?

2. In response to Item No.1 - Earthquake Energy, the staff argues that the magnitude 5.0 "1986 Ohio earthquake" had 3.25%, 1.75%, and 1.94%

of the energy for the respective design components of the SSE. To what extent does that argument support the notion that all magnitude 5.0 earthquakes involve relatively small energy releases?

3. In response to Item No. 3 - Induced Stresses / Effects, the staff states: "In all cases, the quantitative study on margins relative to the design limits indicates the safety margins to be greater than one." What is meant by a safety margin of one? Is this what we normally seek?

4. In response to Item No. 4 - Extrapolation of Induced Stresses, the staff notes that the duration of the strong motion is an important factor. How has staff dismissed the 1986 Ohio earthquake as not having the potential for recurring with a long duration motion?

5. At the end of the memorandum staff states: "The applicant concluded and the staff concurred that if an earthquake similar to the 1986 Ohio earthquake of somewhat higher amplitude and longer duration should occur near the Perry site, the current seismic design and equipment qualification program would still be adequate to ensure that plant equipment and structures would not be damaged." What level of confidence does staff have in this conclusion? Would other qualified experts reach the same conclusion?

cc: Chairman Zech Comissioner Roberts-Comissioner Bernthal Comissioner Carr l OGC SECY 860912006S 060910 PDR ADOCK 05000440 O PDR

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