ML20086M693
| ML20086M693 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 07/20/1995 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20086M686 | List: |
| References | |
| NUDOCS 9507240418 | |
| Download: ML20086M693 (4) | |
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UNITED STATES
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO~ AMENDMENT NO. 101 TO FACILITY OPERATING LICENSE N0. NPF-30
!MION ELECTRIC COMPANY CALLAWAY PLANT. UNIT 1 DOCKET NO. 50-483
1.0 INTRODUCTION
By letter dated September 8, 1994, (Ref. 1) Union Electric Company (UE) requested an amendment to Operating License NPF-30, which would revise the Callaway Plant Technical Specifications (TS) 4.2.2.2, 4.2.2.4, and 6.9.19.
Specifically, the proposed changes would incorporate a penalty in the Core Operating Limits Report (COLR) to account for heat flux (F ) increases greater than 2 percent between monthly surveillance measur,ements.
The UE submittal implements, on a plant specific basis, a generic Westinghouse methodology that has been approved by the NRC staff.
In a letter of October 29,1993, (Ref. 2) Westinghouse Electric Corporation submitted a revision to topical report WCAP-10216-P, Revision l
1, " Relaxation of Constant Axial Offset Control - F, Surveillance Technical Specification," for NRC review. The report describes a methodology developed by Westinghouse for performing power distribution control in Westinghouse-type pressurized-water reactors.
The revision enhances the existing surveillance methodology to account for F, increases greater than 2 percent between measurements.
2.0 BACKGROUND
The heat flux hot channel factor, F,(z), is the maximum local heat flux on the surface of a fuel rod divided by the average fuel rod heat flux.
For those plants using Constant Axial Offset Control (CAOC) or Relaxed Axial Offset Control (RAOC) during normal operation, F (z) is chown to be within a
its limits by performing periodic measurements.
F,(z) surveillance is only required when power has been increased by 10% of rated power from the previous surveillance, or at least once every 31 effective full power days (EFPDs).
The TS take into account the possibility that F (z) may increase between surveillances by requiring that the maximum measu, red F (z) be compared to the maximum F (z) from the nrevious surveillance.,If the maximum F,(z) has increase,d, the TS allow two options: either the current F,(z) must be increased by an additional 2% to account for further increases in F must be reduce $(z) before the next surveillance or the surveillance period to every 7 EFPDs.
i 9507240418 950720 PDR ADOCK 05000483 P.
. would,(change no more than 2% between monthly flux maps.z) penalty of 2% was The F This assumption was based on calculations for previous core designs which pre-date the low leakage loading patterns, high amounts of burnable poisons, and 18-month fuel cycles typical of recent cores.
Recently ce Westinghouse designed cores have experienced increases in measured F w ) as high as 5 to 6 percent between flux maps.
Therefore, a larger penalty is needed on a cycle-specific basis. WCAP-10216-P, Rev. 1 proposed a method to inclade a larger penalty on a cycle specific basis in the plant Peaking Factor Limit Report (PFLR) or in the COLR.
This method was reviewed and approved by the staff.
The licensee has proposed to calculate F (z) penalties using the NRC-approved methods (Ref. 3).
The larger penally will be included in the COLR as a replacement for the current standard 2% value.
3.0 EVALUATION The licensee has proposed changes to TS 4.2.2.2 and TS 4.2.2.4 which specify the surveillance requirements for power distribution limits.
Two TS changes implement the NRC approved Westinghouse methodology to address measured F (z) increases.
For both changes the requirement that F[(z) q should be increased by 2% will be revised to "an appropriate factor specified in the COLR." A third change adds a reference to WCAP-10216-P-A, Rev. I to Administrative Controls, Section 6.9.1.
The staff has determined that this is an appropriate way to implement the Westinghouse methodology at Callaway and finds it acceptable. The staff also performed a review to determine if the Westinghouse generic method applies to Callaway.
Although it was not explicitly addressed in the licensee's submittal, the staff review found that the Westinghouse methodology does apply to the Callaway plant.
The staff finds the proposed TS amendment request acceptable.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Missouri State official was notified of the proposed issuance of the amendment.
The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. The staff has determined that the amendment involves no significant 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 has previously issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public comment on such finding (59 FR 65823). Accordingly, this amendment 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 this amendment.
6.0 CONCLUSION
The staff 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) the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: G. Schwenk Date: July 20. 1995 i
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REFERENCES-(1)
Letter from'D.F. Schnell (ULNRC-3068) to Document Control Desk i
(USNRC) " Heat Flux Hot Channel Factor," September 8,1994.
(2)
Letter from N.J. Liparulo to NRC, WCAP-10126-P, Revision 1,
" Relaxation of Constant Axial Offset Control.- F Surveillance i
Technical Specification," dated October 29, 1993,.
(3)
Letter from A.C. Thadani (NRC) to N.J. Liparulo (Westinghouse),-
" Acceptance for Referencing of Revised Version of Licensing Topical Report WCAP-10216-P, Rev.
l.," dated November 26, 1993.
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