ML20069C727

Application for Amends to Licenses NPF-68 & NPF-81, Relocating Heat Flux Channel Factor,Fq(Z),Penalty of 2 Percent in Spec 4.2.2.2.f to cycle-specific COLR to Allow for burnup-dependent Values of Penalty in Excess of 2%

ML20069C727
Person / Time
Site:	Vogtle
Issue date:	05/20/1994
From:	Mccoy C GEORGIA POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20069C731	List: ML20069C727 ML20069C743
References
LCV-0359, LCV-359, NUDOCS 9406020091
Download: ML20069C727 (8)

Text

i Guoega Power Company 40 Inverres Center Pmkwa/

Post Ohe Bom 1295

• B1rn.ngham. Abibama 3520t l

Telerbotie 205 877 7122 L

C. K. McCoy Georgia Power r itn? southern ekw:.trc systern May 20, 1994 LCV-0359 Docket Nos. 50-424 50-425 U. S. Nuclear Regulatory Cornmission ATTN: Document Control Desk Washington, D. C. 20555 Gentlemen:

VOGTLE ELECTRIC GENERATING Pl ANT REQUEST TO REVISE TECllNICAL SPECIFICATIONS REVISION TO SURVEILLANCE REQUIREMENT FOR HEAT FLUX.llOT CilANNEL FACTOR Fg(7_) Z In accordance with the provisions of 10 CFR 50.90 and 10 CFR 50.92, Georgia Power l Company (GPC) hereby proposes to amend the Vogtle Electric Generating Plant (VEGP) l Unit I and Unit 2 Technical Speci6 cations, Appendix A to Operating Licenses NPF-68 and NPF-81.

This amendment relocates the heat Hux hot channel factor, F Q (Z), penalty of 2 percent in specification 4.2.2.2.f to the cycle-specific Core Operating Limits Report (COLR) to allow for burnup-dependent values of the penalty in excess of 2 percent. This amendment also revises the reference in specification 6.8.1.6 to the Westinghouse FQ(Z) surveillance ,

methodology in order to reflect Revision 1 of WCAP-10216-P, " Relaxation of Constant Axial Offset Control - Fg Surveillance Technical Specification," approved by the NRC on November 26,1993, i Beginning with Unit i Cycle 6, GPC plans to apply the revised methodology Cycle design i calculations show that an FQ(Z) increase of greater than 2 percent is anticipated early in l c cycle life. In order to apply the revised methodology, it is necessary to revise specification 4.2.2.2.f to relocate the FQ(Z) penalty to the COLR and to revise specification 6.8.1.6 to-reference Revision 1 of the topical report WCAP-10216 P. Review of the design and behavior of the current operating cycles for both units indicates that the standard 2-percent FQ(Z) penalty is adequate for the remainder of the cycles. Ilowever, GPC will relocate the standard penalty for the remainder of the current cycle of Unit 2 to the COLR for consistency since the Unit I and Unit 2 Technical Specifications are common.

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l 9406020091 940520 ADOCK 05000424 PDR .

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U. S. Nuclear Regulatory Comrnission Page 2 These changes are requested to be approved by September 30,1994 in order to facilitate use of the revised methodology for Unit 1 Cycle 6 following the upcoming outage scheduled to begin in September 1994.

The proposed changes and bases for the changes are described in Enclosure I to thb letter. Enclosure 2 provides an evaluation pursuant to 10 CFR 50.92 showing that the proposed changes do not involve significant hazards considerations. Instructions for incorporation of the proposed changes into the Technical Specifications and a markup of the affected pages are provided in Enclosure 3.

In accordance with 10 CFR 50.91, the designated state ollicial will be sent a copy of this letter and all enclosures.

hir. C. K. hicCoy states that he is a vice president of Georgia Power Company and is authorized to execute this oath on behalf of Georgia Power Company and that, to the best of his knowledge and belief, the facts set fbrth in this letter and enclosures are true.

GEORGIA POWER CON 1PANY By: ,

C. K. hicCoy Sworn to and subscribed before me this Fo#iy d of d(ud ,1994.

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$0hklh . 01k l Notary Pu6lic

Enclosures:

1. Basis for Proposed Change

2. 10 CFR 50.92 Evaluation

3. Instructions for Incorporation and Revised Pages cc: (See next page) 1.CV-0359 7 twit $

Georgia PUwerkh U. S. Nuclear Regulatory Commission Page 3 c(w): Eco_rgi_a Power Company Mr. J. I3. Beasley, Jr.

Mr. M. Sheibani NORMS U. S. Nuclear Regulatory Commission Mr. S. I). Ebneter, Regional . Administrator Mr. D. S. Ilood, Licensing Project Manager, NRR Mr. B. R. Bonser, Senior Resident Inspector, Vogtle State of Georgia Mr. J. D. Tanner, Commissioner, Department of Natural Resources 1.CV-0359 700775

1 ENCLOSUREI l l

VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS REVISION TO SURVEILLANCE REQUIREMENT FOR HEAT 1 FLUX HOT CHANNEL FACTOR FQ(7J BASIS FOR PROPOSED CHANGE Proposed Changg The specific changes are:

1. In specification 4.2.2.2.f.1, page 3/4 2-5, replace "2%" with "the appropriate factor specified in the CORE OPERATING LIMITS REPORT (COLR)"

2. In specification 4.2.2.2.f.1, page 3/4 2-5, make typographical correction by replacing "4.2.2.d" with "4.2.2.2d."

3. In specification 6.8.1.6, item b, page 6-21, add " Revision l A" afler "WCAP-10216-P-A", and change the date " June 1983" to " February 1994."

Basis Recently, some Westinghouse-designed cores have experienced increases in the measured value of the heat flux hot channel factor, FQ(Z), as high as 5 to 6 percent between monthly measurements over certain burnup ranges. Therefore, the assumption that F Q (Z) will not increase by more than 2 percent over a burnup interval of 31 efTective full power days (EFPD) is not conservative. To address this issue, Westinghouse submitted to the NRC Revision 1 of WCAP-10216-P, " Relaxation of Constant Axial Offset Control- FQ Surveillance Technical Specification," which was approved by the NRC on November 26, 1993. The revised WCAP incorporates minor methodology changes to account for F Q (Z) increases of greater than 2 percent between monthly surveillances.

During n~ nal operation, FQ(Z)is shown to be within its limits by performing periodic measurements. Since FQ(Z) surveillance is required when power has been increased by 20 percent of rated thermal power from the previous surveillance, or at least 31 EFPD, the Technical Specifications (TS) take into account the possibility that FQ(Z) may increase between surveillances. The TS require that when performing the surveillance, the resulting maximum FQ(Z) value must be compared to the maximum Fq(Z) determined from the previous rneasurement. If the maxirnum FQ(Z) has increased smce the previous Z), the TS allow two options: either the current FQ(Z) must be determination increased by an additof Fg(ional 2 percent to account for Qfurther increases in F (Z) next surveillance, or the surveillance period must be reduced to every 7 EFPD.

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ENCLOSURE 1 (CONTINUED)

VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS REVISION TO SURVEILLANCE REQUIREMENT FOR HEAT

}iLUX HOT CHANNEL FACTOR Fg(Z)

B ASIS FOR PROPOSED CHANGE The FQ(Z) penalty of 2 percent was based on the Westinghouse assumption that Fg(Z) would change by no more than 2 percent between monthly flux maps. This assumption was based on calculations for previous core designs that pre-date the low-leakage loading patterns, high amounts of burnable poisons, and 18-month cycles typical of recent cores.

Recently, some Westinghouse-designed cores experienced increases in the measured FQ(Z) as high as 5 to 6 percent between monthly flux maps over certain burnup ranges.

Therefore, for those cores that are predicted to have larger increases in Q F (Z) over certain burnup ranges, a larger penalty will be provided on a cycle-specific basis. The penalties will be calculated using NRC-approved methods.

The burnup-dependent penalty will be included in the cycle-specific Core Operating L,imits Report (COLR) as a replacement to the standard value of 2 percent in tne current TS. The penalty will be presented in tabular form specifying the values, at specific burnups, that are in excess of 2 percent. At all other burnups, the COLR will indicate that the standard 2-percent penalty will still apply.

The stafThas determined that the above-described method for accounting for the additional FQ(Z) penalty, including the relocation of the penalty to the COLR, is acceptable. The staffs conclusions are documented and have been included in the approved topical report WCAP-10216-P-A, Revision l A.

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1 ENCLOSURE 2 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS REVISION TO SURVEILLANCE REQUIREMENT FOR HEAT FLUX HDT CHANNEL FACTOR FQ (Z) l 10 CFR 50.92 EVALUATION l Pursuant to 10 CFR 50.92, Georgia Power Company (GPC) has evaluated the proposed revision to the Technical Specifications (TS) and has determined that operation of the facility in accordance with the proposed amendment would not involve any significant hazards considerations.

The proposed change would revise existing specifications 4.2.2.2.f and 6.8.1.6 so that the Z) would be increased will be specified in the Core Operating Limits factor by which Report (COLR). T Fq(his is based on Revision I to WCAP-10216-P that was ap the NRC on November 26, 1993. The proposed change would incorporate burnup-dependent penalty factors calculated based on NRC approved methodology for core designs that experience monthly increases in measured F Q (Z) greater than 2.0 percent.

1. Does the change involve a significant increase in the probability or consequences of an accident previously evaluated?

The proposed change involves only the manner in which the penalty factors for FQ(Z) would be specified (i. e., a burnup-dependent factor specified in the Core Operating Limits Report (COLR) versus a constant factor specified in the TS).

This is simply used to account for the fact that F Q (Z) may increase between surveillance intervals. These penalty factors are not assumed in any of the initiating events for the accident analyses. Therefore, the proposed change will have no effect on the probability of any accidents previously evaluated. The penalty factors specified in the COLR will be calculated using NRC-approved methodology and will therefore continue to provide an equivalent level of protection as the existing TS requirement. Therefore, the proposed change will not affect the consequences of any accident previously evaluated.

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. 1 ENCLOSURE 2 (CONTINUED) l VOGTLE ELECTRIC GENERATING PLANT J REQUEST TO REVISE TECilNICAL SPECIFICATIONS REVISION TO SURVEILLANCE REQUIREMENT FOR IIEAT FLUX HOT CIIANNEL FACTOR F9(Z) 10 CFR 50,92 EVALUAT_LQN_

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2. Does the chana create the possibility of a new or different kind of accident from  !

any accident p.. .ausly evaluated?

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The proposed change does not involve a physical alteration to the plant (no new or l difTerent kind of equipment will be installed) or alter the manner in which the plant would be operated. Thus, this change does not create the possibility of a new or difTerent kind of accident from any accident previously evaluated.

3. Does this change involve a significant reduction in a margin of safety?

The proposed change will continue to ensure that potential increases in Q F (Z) over a surveillance interval will be properly accounted for. The penalty factors will be calculated using NRC-approved methodology. Therefore the proposed change will not involve a reduction in margin of safety.

COEluSi_QIl Based of the preceding arguments, Georgia Power Company has determined that the proposed changes to the Technical Specifications will not significantly increase the probability or consequences of an accident previously evaluated, create the possibility of a new or difTerent kind of accident from any accident previously evaluated, or involve a significant reduction in a margin of safety. Therefore, the proposed changes meet the requirements of 10 CFR 50.92(c) and do not involve a significant hazards consideration E2-2

ENCLOSURE 3 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECIINICAL SPECIFICATIONS REVISION TO SURVEILL.ANCE REQUIREMENT FOR HEAT FLUX HOT CHANNEL FACTOR F9(Z)

INSTRUCTIONS FOR INCORPORATION The proposed changes to the Vogtle Electric Generating Plant Technical Specifications would be incorporated as follows:

flemove.Pagg insert Page 3/4 2-5* 3/4 2-5*

6-21* 6-21*

• Overleaf page containing no change E3-1

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