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FEB 2 41986 Docket Nos.:
50-275/276 MEMORANDUM FOR: Hans Schierling, Senior Project Manager PWR Prnject Directorate #3 Division of PWR Licensing-A FROM:
Charles E. Rossi, Assistant Director
- nr PWP-A Division of PWR Licensina-A SURJECT:
EVALUATION OF SPENT FUEL RACKS - DIABLO CANYON UNIT 1 & P in the review of the high-density spent fuel rack design and analysis., the staff finds additional information necessary. Attached is a list of questions that the staff needs answered so that the review may proceed.
An advance copy of the attachmant was provided by Frank Rinaldi to you for transmission to the licensee in anticipation of obtaining a timely response.
If you have any ouestions contact F. Rinaldi.
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Charles E. Rnssi, Assistant Director
- or PWR-A Division of PWR Licensing-A
Attachment:
As stated cc:
T. Novak S. Varga D. Vassallo R. Rallard
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D. Jeng i
F. Rinaldi
Contact:
F. Rinaldi X-74708 f
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ADDITIONAL OUESTIONS FOR DIABLO CANYON SPENT FUEL RACK TECHNICAL SPECIFICATION AMENDMENT REVIEW l '.
With respect to the computer code DYNAHIS, discuss specific efforts performed to verify that the code provides realistic seismic responses of the spent fuel racks when subjected to a set of complex loading conditions and geometric constraints.
For example, indicate if experimental data were used as a basis for demonstrating the validity of the code. Provide a discussion of the assumptions and limitations which are unique to the code.
2.
Selected load combination cases, relative geometries of various fuel racks, and multi-directional seismic motions were considered in the fuel rack qualification analyses. Discuss in detail the technical basis for concluding that this approach adequately bounds all the significant cases of fuel rack loads and geometry conditions to ensure the structural intenrity and functionality of the racks.
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