Document: NUREG-0800
Document ID: 73747cf4-ff95-449b-b6b0-53dc0755b9e0
Document Type: srp
Title: OTHER SEISMIC CATEGORY I STRUCTURES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1235/ML12353A382.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.8.4
CFR Part: 
CFR Title: 

Content:
gned as seismic Category I to protect the contained spent fuel assemblies. In addition, it is necessary to evaluate the spent fuel assemblies to ensure that when subject to ASME Service Level D loads, the design material allowable values, when adjusted to the spent fuel pool temperature, will not be exceeded for the spent fuel assembly components. The technical approaches taken by the applicants to demonstrate fuel assembly structural integrity have been diverse, requiring considerable staff effort before a conclusion of structural adequacy could be reached. To address this, the staff formed the Spent Fuel Working Group (SFWG). Based on its assessment of recent applicant submittals, the staff’s SFWG has recommended (1) the addition of secondary review responsibilities assigned to the organization responsible for the review of the fuel system design; and (2) an addendum to Appendix D of SRP Section 3.8.4. The secondary review responsibilities would include the review of the material limits associated with the fuel assembly in the fuel storage racks and the effect of rack deformations on the coolability of the fuel assembly. The addendum to Appendix D would address the apparent deficiency in Appendix D, which is the lack of specific guidance related to establishing an acceptable value for the structural capacity of spent fuel cladding. The SFWG arrived at this conclusion due to the fact that it is apparent that licensees and applicants are able to adequately estimate the loading imparted on a spent fuel bundle. However, the challenge lies in determining whether the cladding can withstand these imparted loads. This challenge is exacerbated by the fact that there is no design code applicable to the structural design of spent fuel 3.8.4-42 Draft Revision 4 – December 2012 rods. In addressing the inconsistency of spent fuel structural integrity reviews, the addendum to Appendix D should afford a greater degree of guidance to reviewers that will facilitate the