ML20065S345

Proposed Tech Spec 4.3.1 Re Number of Fuel Assemblies in Reactor Core

ML20065S345
Person / Time
Site:	North Anna
Issue date:	12/13/1990
From:	VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML20065S343	List: ML20065S341 ML20065S345
References
NUDOCS 9012210008
Download: ML20065S345 (8)

Text

{{#Wiki_filter:. - _ _ - - . _- . - _ _ .- ATTACHMENT 1 PROPOSED TECHNICAL SPECIFICATION CHANGES FOR NORTH ANNA UNITS 1 AND 2 Remove from the previous submittals (Serial Nos. 773 and 773A, dated 1/16/90 and 3/29/90,respectively) pages 5-4 for Unit 1 and 2 Technical Specifications and insert the attached. i l 9012210008 901213 P,DR P ADOCK 05000330 PDR

• DESIGNFEATURES DESIGN PRESSURE ANDTEMPERATURE l l

5.2.2 The reactor containment building is losigned and shat be maintained for a maximum internal pressure of 45 psig and a temperature of 280'F. 1 i 53 REACTORCORE FUEL ASSEMBUES 5.3.1 The reactor core shall contain 157 fuel assemblies with each fuel assembly nominally containing 264 fuel rods clad with Zircaloy 4, except that substitutions of Zircaloy 4 or staint u stool fillor rods may be made in fuel assemblies if justified by the cycle specific reloaa analysis using an NRC approved methodology. A maximum of 5 repaired fuel assemblies, with each repaired fuel asombly containing no more than 3 stainless stool or Zircaloy 4 filler rods may be used por coro design. Each fuel rod shall have a nominal active fuellongth of 144 inches. The inillat coro loading shall have a maximum enrichment of 3.2 weight porcent U-235. Roload fuel shall be similar in phyt!;al design to the initial coro loading and shall have a maximum enrichment of 4.3 wo ght percent U 235. CONTROLROD ASSEMBLIES 5.3.2 The reactor core shall contain 48 fulllongth control rod essemblies. The fulllongth control rod assemblios shall contain a nominal 142 inches of absorber material. The nominal values of absorber matorial shall be 80 porcont silver,15 porcent indium and 5 percent cadmium. All control rods shall be clad with stainless steel tubing.- 5.4 REACTORCOOLANTSYSTEM DESIGN PRESSURE ANDTEMPERATURE, 5.4.1 The reactor coolant system is designed and shall be maintained: NORTH ANNA UNIT 1 54

DESIGN FEATURES 5.3 REACTORCORE FUEL ASSEMBUES 1 5.3.1 The reactor core shal! contain 157 fuel assemblies with each fuel assembly nominally containing 264 fuel rods clad with Zircaloy 4, except that substitutions of Zircaloy 4 or i stainless steel filler rods may be made in fuel assemblies if justified by the cycle specific  ! reload analysis using an NRC approved methodology. A maximum of 5 repaired fuel assemblies, with each repaired fuel assembly containing no more ;han 3 stainless steel or Zircaloy 4 filler rods may be used per core design. Each fuel rod sht have a nominal active fuel length of 144 inches. The initial core loading shall have a maximum enrichment of 3.2 weight percent U-235. Reload fuel shall be similar in physical design to the initial core loading and shall have a maximum enrichment of 4.3 weight percent U 235. C ONTROL ROD ASSiiMBUES 5.3.2 The reactor core shall contain 48 full length control rod assemblies. The full length control rod assemblies shall contain a nominal 142 inches of absorber material. The nominal values of absorber material shall be 80 percent silver,15 percent indium and 5 percent cadmium. All control rods shall be clad with stainless steel tubing. 5.4 REACTORCOOLANT 3YSTEM DESIGN PRESSURE AND TEMPERATURE 5.4.1 The reactor coolant system is designed and shall be maintained:

a. In accordance with the code requirements specified in Section 5.2 of the FSAR, with allowance for normal degradation pursuant to the applicable Surveillance Requirements.

b. For a pressure of 2485 psig, and I

c, .For a temperature of 650*F, except for the pressurizer wnich is 680'F. VOLUME 5.4.2 The total water and steam volume of the reactor coolant system is 9957 i '3 cubic feet at a nominal Tavg of 525'F. NORTH ANNA UNIT 2 54 1

s ATTACHMENT 2 MARKUP OF THE NORTH ANN'4 MERITS

_ . - - _ . _ _ . _ _ . _ . _ . _ . _ _ . _ . . . _ . _ _ . _ _ _ . _ . - . _ _ . _ _ .- m. _ DESIGN FEATURES 4.0 4.0 DESIGN FEATURES (continued) , 4.3 REACTOR CORE 4.3.1 Euel Assemblies . dim /@# The reactor core shall contain 157 fuel assemblies with each fuel

               -yogfoff //y                                      assembly 9containing 264 fuel rods clad with Zircaloy 47 Each fuel rod shall have a nominal active fuel length of 144 inches
                                                              --and-centain+ maximum-total-weight-of-1780 grams-uraniumr- The initial core loading shall have a maximum enrichment of 3.2 weight percent U 235. Reload fuel shall be similar in physical                        ,

design to the initial core loading and shall have a maximum enrichment of 4.3 weight percent U 235. 4.3.2 control Rod Assemblies The reactor core shall contain 48 full length control rod assemblies. The full length control rod assemblies shall contain a nominal 142 inches of absorber material. The nominal values of absorber material shall be 80 percent silver, 15 percent inditM and 5 percent cadirium. All control rods shall be clad with ' stainless steel tubing. (continued) g2ypt that subadiMioco c/ ?tignatcy-y 08 JdaiN/eso Sdct/ fi//cA' Aca'6 A'/k/ ne m/?drw llic/ Anor/1/ies if jushfled hj N1r dyaler 3,Oed/AC /kibad am/pic gaiq ay AJhD-dpqMouednWkdotogc(, A pyt4'uirt sA c-bp0 aired A33fD/b/&y OmfJwhJy DO 0?d's h'?OD 0 krf3,2KL /93-W?ln,1, /?!AL'adf j //350'/W' GN Nf7N. Nor , Anna Units 1 & 2 45 Amendment Nos. xxx & yyy

ATTACHMENT 3 Discussion of Proposed Changes and 10 CFR 50.92 SIGNIFICANT HAZARDS DETERMINATION u_ . _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ __

Discussion of Proposed Chanaes The current operating philosophy at Virginia and Electric Power Company prohibits the use of fuel assemblies with known failed rods. Failed rods are defined as fuel rods having cladding defects allowing fission products to be released to the coolant. By replacing the failed rods with solid filler rods rnade from either stainless steel or Zircaloy 4 during a fuel assembly reconstitution, the Company is able to recover cost from fuel assemblies that are prematurely discharged because of the existence of failed rods. The current Technical Specifications for each Unit preclude the use of solid filler rods. The Design Features Section of the North Anna Units 1 and 2 Technical Specifications (Section 5.3.1 of each Unit's Technical Specifications) states that each fuel assembly will contain 264 fuel rods clad with Zircaloy 4. The proposed changes supplement our initial amendment request dated January 16, 1990 which proposed an unlimited use of filler rods and allows the use of open water channels. However, after discussion with the NRC it is our understanding that NRC Generic Letter 90 02, which dealt with this issue, will be revised to disallow an unlimited use of filler rods and open water channels. The attached changes propose a limit of 5 repaired fuel assemblies per core containing no more than 3 solid stainless steel or Zircaloy 4 filler rods per assembly. The limit of 5 repaired fuel assemblies was chosen for core symmetry reasons to allow a potential of 4 symmetrical assemblies and 1 center assembly to be replaced if necessary. The limit of no more than 3 rods per assembly was chosen based on experience. To date, we have not had need to reconstitute more than 3 rods per assembly. Open water channels will not be permitted per the attached amendments. Accordingly, Section 5.3.1, Fuel Assemblies is revised to state "A maximum of 5 repaired fuel assemblies, with each repaired fuel assembly containing no more than 3 stainless steel or Zircaloy 4 filler rods may be used per core design." The analysis discussed in our original license amendment proposal submitted January 16,1990 envelopes the limited application now proposed. 1 { l

Slanifltant Hazards Determination It has been determined that the proposed changes to revise the previously submitted licensing amendments (letters dated January 16,1990 and March 29,1990) do not involve a significant hazards consideration as defined in 10 CFR 50.92. This determination was based on the following points.

1. The proposed changes do not significantly increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated in the safety analysis report. In fact, the proposed change will have no impact on the probability of occurrence or the consequences of an accident or malfunction of equipment. The only changes from the original submittal (dated January 16,1990) are the restriction on the number of stainless steel or Zircaloy 4 filier rods to be used per cycle and the disallowance of open water channels.

2, The proposed amendment will not create the possibility of a new or different kind of accident from any accident previously evaluated. No physical changes or modifications are being made to the plant or its equipment. As noted above, the only changes are an additional restriction en the number of stainless steel or Zircaloy 4 filler rods and the disallowance of open water channels from our onginal submittal.

3. The proposed amendment does not involve a significant reduction in a margin of safety. No physical char,ges or modifications are being made to the plant or its equipment. No changes are being made to the cycle specific reload analysis. As previously stated, the only changes are an additional restriction on the number of stainless steel or Zircaloy 4 filler rods and the disallowance of open water channels from our original submittal.

Therefore, the proposed changes do not involve a significant reduction in a margin of safety. Based on the above, we have determined that the amendment request does not (1) involve a significant increase in the probability or consequences of an accident previously evaluated, (2) create the possibility of a new or different kind of accident ' from any accident previously evaluated, or (3) involve a significant reduction in a margin of safety; and therefore does not involve a significant hazards consideration. =_. . . . -}}