ML20082M992
| ML20082M992 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 08/22/1991 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20082M987 | List: |
| References | |
| NUDOCS 9109060130 | |
| Download: ML20082M992 (2) | |
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WASHINoToN, D.C. 20066 V.... + f SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 48 TO FACILITY OPERATING LICENSE NO. NPF-42 WOLF CREEK NUCLEAR OPERATING CORPORATION WOLF CREEK GENERATING STATION DOCKET NG. 50-482 j.
1.0 INTRODUCTION
j-By application dated May 14, 1991, the Wolf Creek Nuclear Operating Corporation (the licensee) requested changes to the Technical Specifications (Appendix A to Facility Operating License No. NFF-42) for the Wolf Creek Generating Station.
The proposed chances would revise Technical Specification S.3.2 " Control Rod Assemblies," to allow the use of a silver-indium-cadmium (Ag-In-Cd) as the j.
neutron absorbing material in control rods.
Technical Specification 5.3.2 currently specifies hafnium as the neutron absorbing material.
The preposed revision would allow the use of the hafnium control rods, Ag-In~Cd control rods, 4
or a mixture of both types.
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- 2. 0 DISCUSSION-II Wolf = Creek Generating Station currently uses hafnium as the absorber material in rod cluster control assemblies (RCCAs).
Prior to the use of hafnium, Ag-In-Cd i
was the material most widely used in RCCAs for Westinghouse plants. Wolf Creek was originally designed to use Ag-In-Cd RCCAs, but changed to hafnium prior to the initial fuel loading.
Ag-In-Cd has continued to he used in many plants, I
and as such, a large amount of operating experience has been gained with Ag-In-Cd-used as an absoroer material.
Ag-In-Cd has proven to' tse an ef fective absorber
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. material and RCCAs with Ag-In-Cd have shown very good operating results, f;
3.0 EVALUATION 1
Hafnium and Ag-In-Cd RCCAs are interchangeable.
T'e physical dimensions of the RCCAs are identical as are the materials of the spider assembly and the.rodlet cladding.
The rod drop times and the rod worths for the two absorber types are j _
expected to be equivalent.
As additional assurance, both the rod drop! times-and rod worths are verified by testing during startup tests following each refueling
-outage.
The use of Ag-In-Cd absorber material in RCCAs is consistent with.all
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assumptions of the transient and accident ~ analyses of record _for Wolf Creek since-i the RCCAs will meet the same mechanical, nuclear and thermal hydraulic limits as the original RCCAs.
Since they are equivalent, a mixture of absorber types is permitted with no adverse impact on plant safety,
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3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Kansas state official was notified of the proposed issuance of the amendment.
The state official had no comments.
4.0 ENVIRONiENTAL CONSIDERATION The amendment chrnges a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20.
The NRC staff has determined that the amendment involves no signifi~ cant increase in the amounts, and no significant change in-the types, of_any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure.
The Commission haa previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (56 FR 27051).
Accordingly, the amendrnent meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
5.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) tt.e issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
Douglas V. Pickett, PDIV-2, NRR Dats.
August 22, 1991
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