Agenda - 01-19-1999 - 9b1 - Laserfiche WebLink

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WAIS Document Retrieval is not created. 3. Involve a significant reduction in the margin of safety. The function of the Spent Fuel Pool is to store the fuel assemblies in a subcritical and coolable configuration through all environmental and abnormal loadings, such as an earthquake or fuel assembly drop. The new rack design must meet all applicable requirements for safe storage and be functionally compatible with Pools 'C' and 'D'. CP &L has Addressed the Safety Issues Related to the Expanded Pool Storage Capacity in the Following Areas: 1. Material, mechanical and structural considerations. The mechanical, material, and structural designs of the new racks have been reviewed in accordance with the applicable provisions of the NRC Guidance entitled, "Review and Acceptance of Spent Fuel Storage and Handling Applications''. The rack materials used are compatible with the spent fuel assemblies and the Spent Fuel Pool environment. The design of the new racks preserves the proper margin of safety during normal and abnormal loads. It has been shown that such loads will not invalidate the mechanical design and material selection to safely store fuel in a coolable and subcritical configuration. 2. Nuclear Criticality The methodology used in the criticality analysis of the expanded Spent Fuel Pool meets the appropriate NRC guidelines and the ANSI standards (GDC 62, NUREG 0800, Section 9.1.2, the OT Position for Review and Acceptance of Spent Fuel Storage and Handling Applications, Reg. Guide 1.13, and ANSI /ANS 8.17). The margin of safety for subcriticality is maintained by having the neutron multiplication factor equal to, or less than, 0.95 under all accident conditions, including uncertainties. This criterion is the same as that used previously to establish criticality safety evaluation acceptance and remains satisfied for all analyzed accidents. 3. Thermal - hydraulic and Pool Cooling The thermal - hydraulic and cooling evaluation of the pools demonstrated that the pools can be maintained below the specified thermal limits under the conditions of the maximum heat load and during all credible accident sequences and seismic events. The pool temperature will not exceed 137 deg.F during the highest heat load conditions. The maximum local water temperature in the hot channel will remain below the boiling point. The fuel will not undergo any significant heat up after an accidental drop of a fuel assembly on top of the rack blocking the flow path. A loss of cooling to the pool will allow sufficient time ( >13 hours) for the operators to intervene and line up alternate cooling paths and the means of inventory make -up before the onset of pool boiling. The thermal limits specified for the evaluations performed to support the proposed activity are the same as those that were used in the previous evaluations. It has also been demonstrated that adequate margin exists in the Unit 1 CCW system to support near term operation of the pools subject to the requirements of the proposed changes to the Technical Specifications. Based on the preceding discussion it is concluded that this activity does not involve a significant reduction in the margin of safety. The NRC staff has reviewed the licensee's analysis and, based on this review, it appears that the three standards of 10 CFR 50.92(c) are satisfied. Therefore, the NRC staff proposes to determine that the Page 5 of 8 http: / /frwebgate2. acces ... /waisgate.cgi ?WAISdocID= 341284846 +0 +0 +0 &WAISaction = retriev 1/14/99