ML19289C849

Anticipates Need for Addl Info Re Seismic Design Bases to Compare Current Criteria as Part of Systematic Evaluation Program.Expects to Focus on Significance of Newer Seismic Design Techniques

ML19289C849
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	01/15/1979
From:	Stello V Office of Nuclear Reactor Regulation
To:	Bixel D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
References
NUDOCS 7901250302
Download: ML19289C849 (3)

Text

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UNITED STATES j

NUCLEAR REGULATORY COMMISSION g

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y WASHINGTON, D. C. 20555 e8 January 15, 1979 g, *...f Docket No. 50-155 uoasumers Power Company ATTH:

Mr. David A. Bixel Nuclear licensing Administrator 212 West Michigan Avenue Jackson, Michigan 49201 Gentlemen:

RE: BIG ROCK POINT As part of the Systematic Evaluation Program (SEP) the NRC staff has completed a search of your docket for pertinent infomation related to the seismic design bases of your facility. We find that your docket lacks sufficient infomation concerning the seismic design input and structural capability for safety-related structures, systems and equip--

ment to withstand earthquake effects to enable us to complete our evaluation.

As you know, the major NRC regulations dealing with seismic design are 10 CFR Part 50, Appendix A (General Design Criterion 2) and 10 CFR Part 100, Appendix A.

We recognize that both of these regulations were issued subsequent to the design of your facility. However, one of the objectives of the SEP is to campare the original design basis with current criteria. Currently, the infomation on the docket is not sufficiently cmplete to adequately address the potential hazard of earthquakes, nor to detemine whether backfitting of additional seismic resistance would provide substantial additional protection required for safety.

We recognize that your facility possesses inherent structural capabili-ties to withstand earthquake effects. However, there is insufficient infomation docketed to adequately quantify such capability. We believe that a significant effort on your part may be required to assess the seismic safety margins of your facility. This matter has been generally discussed with your representatives, as part of the SEP, to assure that the issue will be properly resolved within the time frame of the SEP..

790125030>

i Consumers Power Company January 15, 1979 j

I While the docket does not contain sufficient information on geologic and seismic input to allow a comparison to current criteria, seismic input i

information for your facility could be developed based on current c..;eria j

and a bounding conservative assessment; however, evaluation of various f

site specific response spectra methodologies may demonstrate a more realistic approach in determining seismic input. Staff effort in these l

methodologies is expected to lead to acceptable procedures for determining i

site specific spectra. We encourage you to closely follow the progress i

of our work aimed at the development of a seismic input for your facility.

[

Although we have undertaken this seismic input effort, we expect you to l

be responsible for a documented seismic design basis for your facility.

In addition to seismic input, this would include analytical or other pro-i cedures for demonstrating that acceptable structural design criteria are satisfied. The staff expects *w work with you in this effort, especially in the areas of definition of acceptable seismic structural design criteria 3

and seismic input.

If you wish to follow such an approach, as suggested by the staff, please infonn us within 30 days. Additionally, please provide, within the next 90 days, a description outlining your program for documenting a seismic design basis and a program schedule. To provide maximum assurance that both the scope and schedule are acceptable, we suggest that detailed working j

meetings for your facility in the next 90 days would be beneficial.

=

incerely, l

I k

^

p r S ello,

., Di or Division of Operating Reactors Office of Nuclear Reactor Regulation cc:

See next page l

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Consumers Power Company January 15, 1979 CC:

Mr. Paul A. Perry, Secretary Consumers Power Canpany 212 West Michigan Avenue Jackson, Michigan 49201 Judd L. Bacon, Esquire Consumers Power Company 212 West Michigan Avenue Jackson, Michigan 49201 Hunton'& Williams George C. Freeman, Jr., Esquire P. O. Box 1535 Richmond, Virginia 23212 Peter W. Steketee, Esquire 5C5 Peoples Building Grand Rapids, Michigan 49503

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