ML20024F630

Forwards Revised Table 1 & Figure 1 to Cycle 4 Reload Ser. Revs Necessary Due to Changeout of Fuel Assembly & Rod Cluster Control Assembly Damaged During Placement of Upper Internals

ML20024F630
Person / Time
Site:	Beaver Valley
Issue date:	09/01/1983
From:	Carey J DUQUESNE LIGHT CO.
To:	Varga S Office of Nuclear Reactor Regulation
References
TAC-52287, NUDOCS 8309090536
Download: ML20024F630 (4)

Text

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'At5 Telephone (412) 3934000 Nuclear Division P.O. Box 4 Sh'ppingport, PA 1507T-0004 September 1, 1983 Directcr of fluclear Reactor Regulation United States fluclear Regulatory Commission Attn: fir. Steven A. Varga, Chief Operating Reactors Branch No. 1 Division of Licensing Washington, DC 20555

Reference:

Beaver Valley Power Station, Unit No.1 Docket No. 50-334, License No. DPR-66 Cycle 4 Reload Safety Evaluation Report Revision Centlemen:

Enclosed are ten (10) copies of revised Table 1 and Figure 1 of the Beaver Valley Power Station, Unit flo.1 Cycle 4 Reload Safety Evalua-tionReport(RSER). The revisions are necessary due to the changeout of the fuel assembly and Rod Cluster Control Assembly (RCCA) that were damaged during placement of the upper internals following fuel shuffle.

The upper internals had been reworked during the refueling outage to replace the control rod guide tube support pins which are used to align the bottom of the control rod guide tube assembly into the top of the upper core plate. When installing the upper internals in the reactor vessel, a control rod guide tube support misalignment in the K-2 position (Figure 1) caused a downward deflection of the fuel assembly, therefore, that fuel assembly and control bank A RCCA will be removed from the core.

A new core loading pattern has been developed and is shown in revised Figure 1 attached. The new core loading pattern involves removal of the fuel assembly at the K-2 position and replacing it with the fuel assembly j from the R-8 position. The new core loading pattern utilizes a new RCCA in core location K-2. The neutron absorption properties of the new RCCA are the same as the RCCA it replaces in that core location. The over-all result is that there is no change in the Reload Safety Analyses Check-list (RSAC) limits and results of the Cycle 4 RSER due to utilizing the new RCCA. A new 3.1% enrichment Region 6A fuel assembly will then be placed in the R-8 position. This position was chosen for the new fuel assembly since this will minimize the effects on power distribution and core peaking factors.

The following differences exist between Region 6 and Region 6A fuel:

1. Backfill pressure - The fuel rod backfill pressure for the Region 6A fuel assembly is 450 psig while the Region 6 i fuel backfill pressure is 350 psig. The difference in backfill pressure does not affect the RSAC or RSER for 001 Cycle 4 since the red internal pressure curve used in the gg Cycle 4 analyses was for a higher and more conservative pressure of 500 psig, 536 eso9og PkokT0CK05000334 PDR j

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Braver Valley Power Station, Unit No.1 Docket No. 50-334, License No. DPR-66 Cycle 4 Reload Safety Evaluation Report Revision Page 2

2. Grid design - Region 6 fuel assemblies have grid modifi-cations consisting of additional guide vanes and tabs along with the corner surface condition incorporated into Region 5 fuel assemblies. The Region 6A fuel assembly has the same corner surface condition incorporated into Region 5 fuel assemblies but does not have the additional guide vanes and tabs that Region 6 fuel assemblies have.

3. Bottom nozzle - The Region 6A fuel assembly does not have a reconstitutable bottom nozzle design that Region G fuel assemblies have. Its bottom nozzle design is like the Region 5 fuel assembly design.

Revised Table 1 attached, identifies the new fuel assembly as Region 6A, with an enrichment of 3.1%. The burnups have also been revised to indicate the actual region average burnup achieved during Cycle 3 and the approximate burnup predicted for the end of Cycle 4.

We have completed our evaluation of the new core loading pattern, utilizing the methodology described in WCAP-9273, " Westinghouse Reload Safety Evaluation Methodology", with respect to core peaking factors, power distributions and RSAC limits. This evaluation has assured us that the results and conclusions of the Cycle 4 RSER we submitted to you May 23, 1983 are still valid. We have confirmed that there is no change to the Radial Peaking Factor Limit Report (RPFLR) due to the new loading pattern, therefore, the Cycle 4 RPFLR is still applicable.

Therefore, Table 1 and Figure 1 in your copy of the BVPS-1 Cycle 4 RSER should be deleted and the attached revised versions should be inserted.

The text of the RSER will be revised to incorporate the Region 6A fuel assembly and will be forwarded to you when complete.

The Beaver Valley Onsite Safety Committee (OSC) and the Duquesne Light Offsite Review Committee .(0RC) have reviewed the revisions to l

the RSER and concluded that no unreviewed safety questions, as defined by 10CFR50.59, are involved with the revisions to the reload core design.

i Very truly yours,

. J. Carey i Vice President, Nuclear

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Mr. W. M. Troskoski, Resident Inspector U. S. Nuclear Regulatory Commission Beaver Valley Power Station Shippingport, PA 15077 l-U. S. Nuclear Regulatory Commission c/o Document Managment Branch i Washington, DC 20555 i

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Figure 1

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CORE LOADING PATTERN

• BEAVER VALLEY UNIT 1 CYCLE 4 R P N M L K- J- H G F E D C B A 4 6 4 )

4 6 6 4 6 6 4 2 .

(4) (4) 6 5 5 4 5 5 6 4 3 4

(12) SS (12) 4 5 6 5 6 5 6 5 6 5 4 4 (12) (20) (20) -

(12) 4 6 6 4 4, 5 5 5 4 4 6 6 4 -5 (12) (4) (12) 5 4 5 6 4 6 5 4 5 5 6 6 6 _5 (12) [20) (20) (12) 4 6 5 6 5 6 4 5 4 6 5 6 5 6 4 (4) (20) (20) :20) (20) (4) 4A 5 4 5 1 5 4 5 5 4A 4 6 8 6A 4 5 (4) (4) 4 5 4 6 5 6 5 6 4 9 4 6 5 6 5 6 (20) (20) (20) (20) (4)s (4) 5 5 4 5 6 4 6 5 4 5 5 6 10 6

(12) '20) (20) (12) 6 4 4 5 5 5 4 4 6 6 4 -11 4 6 (12) (4) '12) 5 6 5 6 5 6 5 6 5 4 12

4. ~

(12) (20) (20) (12) 4 6 5 5 4 5 5 6 4 13 (12) SS (12) 4 6 6 4 6 6 4 14 (4) (4) ,

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4 6 4 15 c

X - Region Number (Y) - Number' of Absorber Rods

• SS - Secondary Source Rods

• Applicable for both the WABA rod and the standard burnable absorber rod usage _

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TABLE 1 BEAVER VALLEY UNIT 1 - CYCLE 4 FUEL ASSEMBLY DESIGN PARAMETERS **

REGION I 4 4A* 5 6 6A

. Enrichment (w/oU-235)+ 2.106 3.199 3.203 2.999 3.25 3.10 D:nsity (% Theoretical)+ 94.80 94.38 94.38 94.34 94.5 94.5 Number of Assemblies 1 50 2 52 51 1 Approximate Burnup at 13,800 20,700 21,700 9,200 0 0 B: ginning cf Cycle 4 (MWD /MTU)

Approximate Burnup 25,200 30,060 35,000 23,200 13,000 7,730 Predicted for EOC 4 Region Average

• Optimized Fuel -

Zirc grid

+. All fuel regions are as-built values except Region 6 and 6A which are nominal values.

• • Applicable to either the WABA design or the standard burnable absorber design.

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