Document: NUREG-0800
Document ID: 080f80e5-ae24-4b03-bcdf-a2bdfc747da6
Document Type: srp
Title: Revision 3 - March 2007
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070790015.pdf
Revision Date: 2023-06
Chapter: 4
Section ID: 4
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pectrum of BTP 4-1-2 Revision 3 - March 2007 operating and soon-to-be-operating reactors) and showed that most plants could meet the requirements of 10 CFR 50 Appendix K and 10 CFR 50.46 (i.e., 1204EC (2200EF)) peak clad temperature) if the value for FQ were less than 2.32. Westinghouse also showed that CAOC procedures employing a ± 5-percent target band would limit peak FQ for each of these reactors to less than 2.32. The staff recognized at that time, however, that not all plants needed to maintain FQ below 2.32 to meet fuel acceptance criteria (FAC) or needed to operate within a ± 5-percent band to achieve a value for FQ less than 2.32. In fact, Point Beach was allowed to operate within a wider band because the Wisconsin Electric Power Company demonstrated to the NRC’s satisfaction that the reactors could be maneuvered within a wider band (+6, -9 percent) and still hold FQ below 2.32. The staff fully expected that in time most plants would have individual CAOC analyses and procedures tailored to the requirements of their plant-specific ECCS analyses. Therefore, when the staff accepted CAOC, it was not just FQ value equal to 2.32 and a ± 5- percent bandwidth the staff were approving, but the CAOC methodology. This is analogous to the staff’s review and approval of ECCS and fuel performance evaluation models. The CAOC methodology, which is described in WCAP-8385 and WCAP-8403, entails (1) establishing an envelope of allowed power shapes and power densities, (2) devising an operating strategy for the cycle which maximizes plant flexibility (maneuvering) and minimizes axial power shape changes, (3) demonstrating that this strategy will not result in core conditions that violate the envelope of permissible core power characteristics, and (4) demonstrating that this power distribution control scheme can be effectively supervised with ex-core detectors. Westinghouse argues that point 3, in the CAOC methodology above (i.e., demonstrating the core conditions will