ML20247H284

Proposed Tech Specs Re Types of Absorber Matls in Control Rod Assemblies

ML20247H284
Person / Time
Site:	Byron, Braidwood, 05000000
Issue date:	05/22/1989
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML20247H274	List: ML20247H269 ML20247H284
References
NUDOCS 8905310203
Download: ML20247H284 (4)

Text

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r DESIGN FEATURES

5. 3 REACTOR CORE FUEL ASSEP_P' I,ES 5.3.1 The core shall contain 193 fuel assemblies with each fuel assembly containing 264 fuel rods clad with Zircaloy-4, except that limited substitution of fuel rods by filler rods consisting of Zircaloy-4 or stainless steel or by vacancies may be made if justified by a cycle specific reload analysis. Each fuel rod shall have a nominal active fuel length of 144 inches. The initial core loading shall have a maximum enrichnent of less than 3 20 weight percent U-235. Reload fuel shall be similar in physical design to she initial core '

loading and shall have a maximum enrichment of 4.0 weight percent U-235.

CONTROL ROD ASSEMBLIES l

5.3.2 The core shall contain 53 full-length and no part-length control rod l assemblies. The full-length control rod assemblies shall contain a nominal 142 inches of absorber material. All control rods shall be hafnium,gclad with stainless steel tubing. ,

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5.4 REACTOR COOLANT SYSTEM a,;f,.g fos, m a se DESIGN PRESSURE AND TEMPERATURE l 5.4.1 The Reactor Coolant System is designed and shall be maintained:

a. In accordanc: 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

c. For a temperature of 650 F, except for the pressurizer which is 680 F. >

VOLUME 5.4.2 The total water and st2am volume of the Reactor Coolant System is 12,257 cubic feet at a nominal T,yg of 588.4 F.

5. 5 METEOROLOGICAL TOWER LOCATION 5.5.1 The meteorological tower shall be located as shown on Figure 5.1-1.

8905310203 DR 890522 p ADOCK 05000454 l PNV -

BYRON - UNITS 1 & 2 5-4 AMEN 5 MENT N0. 7

DESIGN FEATURES 5.3 REACTOR CORE FUEL ASSEMBLIES 5.3.1 The core shall contain 193 fuel assemblies with each fuel assembly containing 264 fuel rods clad with Zircaloy-4, except that limited substitu- '

tion of fuel rods by filler rods consisting of Zircaloy-4 or stainless steel or '

by vacancies may be made if justified by a cycle specific reload analysis.

Each fuel rod shall have a nominal active fuel length of 144 inches. The initial core loading shall have a maximum enrichment of less than 3.20 weight ,

percent U-235. Reload fuel shall be similar in physical design to the initial core loading and shall have a maximum enrichment of 4.0 weight percent U-235.

CONTROL R00 ASSEMBLIES f; i

5.3.2 The core shall contain 53 full-length and no part-length control rod j assemblies. The full-length control rod assemblies shall contain a nominal ,

142 inches of absurber material. All' control rods shall be hafnium,ac lad with '

stainless steel tubing.

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$/Kr~~ Ibdium - Cadmum, o 5.4 REACTOR COOLANT SYSTEM e mg g of g g DESIGN PRESSURE AND TEMPERATURE a

1. N 5.4.1 The Reactor Coolant System is designed and shall be maintained: l

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

b. For a pressure of 2485 psig, and

c. For a temperature of 650 F, except for the pressurizer which is 680 F.

VOLUME 5.4.2 The total water and steam volume of the Reactor Coolant System is 12,257 cubic feet at a noinina", T,,g cf 588.4 F.

5.5 METEOROLOGICAL TOVER LOCATION 5.5.1 The meteorological tower shall be located as shown on Figure 5.1-3. ,

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BRAIDWOOD - bHITS 1 & 2 5-4 L - __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

4 Y d AIIAOIMMI_E EVALUATI.QN OF SIGNIFIfATLQ!i_EAKARES CONSIDIEATIONS Commonwealth Edison has evaluated this proposed snendment and determined that it involves no significant hazards considerations. According te 10 CFR 50.92(c), a proposed amendment to an operating license involves no significant hazards considerations if operation of the facility in accordance with the proposed snendment would not

1. Involve a signification increase in the probability or consequences of an accident previously evaluated; or

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.

The proposed change does not 'sult in a significant increase in the probability or consequer _es of accidents previously evaluated. The probability for an accident is independent of the absorber material used in the Rod Control Cluster Assembly (RCCA).

The consequences remain unchanged because the silver, indium, cadmium absorber material meets the mechanical, physical, nuclear, and thermal properties assumed in the accident analysis.

The proposed changes does not create the possibility for a new or different kind of accident from those previously evaluated.

The physical characteristics of the silver, indium, cadmium RCCA's are comparable to that of the hafnium RCCA's. The physical size and construction of the RCCA's is the same. Doth absorbers exhibit similar neutron absorption characteristics, hence flux distribution 9.nd shutdown margins will remain within limits.

The weights of the two differing RCCA's are comparable.

Rod drop times will remain well within the values assumed in the FSAR. Both absorber material are compatible with reactor coolant and reactor materials.

The proposed change does not involve a reduction in the t

margin to safety. All se.fety limits and limiting conditions for operation will continue to ho net. The use of silver, indium, ca&nium RCCA's is consistent with all assumptions made in the

, uccident analysis. Silver, indium, cadmium is currently in use at several Westinghouse plants. This absorber material has been shown through experience to be an effective and stable material, q I

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l ATTACHMEtLT_D

- EliVIRONMENTAL ASSESSMENT STAIgtiEUJ Commonwealth Edison has evaluated the proposed amendment agalust the criteria for and identification of licensing and regulatory actions requiring environment assessment in accordance with 10CFR51.21. It has been determined that the proposed change meets the criteria for a categorical exclusion as provided for under 10CFR51.22(c)(9). This determination was based on the fact that this change is being proposed as an amendment to a license issued pursuant to 10CFR50 and the change involves changes to the use of components located within the restricted area, and it involves no significant hazard considerations. There are no changes in the type or amounts of effluents released offsite, and there is no significant increase in individual or cumulative occupation 91 radiation exposure.

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