ML20247H269

Application for Amends to Licenses NPF-37,NPF-66,NPF-72 & NPF-77,revising Tech Spec 5.3.2 to Allow Use of Either Hafnium or silver-indium-cadmium,or Combination of Both,As Absorber Matl in Rod Control Cluster Assemblies

ML20247H269
Person / Time
Site:	Byron, Braidwood, 05000000
Issue date:	05/22/1989
From:	Chrzanowski R COMMONWEALTH EDISON CO.
To:	Murley T Office of Nuclear Reactor Regulation
Shared Package
ML20247H274	List: ML20247H269 ML20247H284
References
NUDOCS 8905310201
Download: ML20247H269 (4)

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• '* } Comm:nwealth Edison

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, 'I .. ? 72 West Adams Street. Chicago, Illinois I.

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1. \ L' / Chicago Illinois 60690 - 0767/ Address Reply to. Post OfficiiFoT7(if~

May 22, 1989 Dr. Thomas E. Murley, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Machington, DC 20555

Subject:

Byron Station Units 1 and 2 Braidwood Station Units 1 and 2 Application for Amendment to facility Operating Licenses NPF-37, NPF-66, NPF-72, and NPF-77 FRC Docket _,tipfu 50-454/155_and 50-456/451

Dear Dr. Murley:

Pursuant to 10 CFR 50.90, Commonwealth Edison proposes to amend Appendix A, Technical Specifications of Facility Operating Licenses NPF-37, NPF-66, NPF-72, and NPF-77. The proposed amendment requests changes to specification 5.3.2 to allow the use of either halfnium, or silver-indium-cadmiun, or a combination of both, as the absorber material in the rod control cluster assemblies.

The description and summary of the proposed changes are presented in Attachment A. The revised Technical Specification pages are contained in Attachment B.

The proposed changes have been reviewed and approved by both on-site and off-site review in accordance with Commonwealth Edison procedures.

Commonwealth Edison had reviewed this proposed amendment in accordance with 10 CFR 50.92(c) and has determined that no significant hazards consideraiton exists. This evaluation is documented in Attachment C.

Commonwealth Edison has evaluated the proposed amendment with the requirement of 10 CFR 51.21. Attachment D contains the corresponding Environmental Assessment Statement.

Braidwood Station will be inspecting all Halfnium rod coutrol cluster assemblies during the Fall 1989, Unit 1 refueling outage. Commonwealth Edison j would like to replace any co.ittol rods found to have defects, thnt could j impare operability, with silver-indium-cadmium control rods. Due to the ]

potential of replacing control rods, Commonwealth Edison requests opproval and j issuance of this porposed amendment prior to October 16, 1989, i

8905310201 090522 /hkr/2, PDR ADDCK 05000454 P PNU fd

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i Commonwealth Edison is notifying the State of Illinois of our application for this amendment by transmitting a copy of this letter and it.2

. attachments tb the designated State Offical.

Please direct any questions you may have concerning this e.atter to this office.

Very truly yours, AtdZ4) ,

R. A. hrzanows i i Nuclear Lice sing Administrator l

/sc1:0129T:1-2 Attachments: A) Description and Sun. .x B) Proposed Technical Specification Changes

.C) Evaluation of Significant Hazards Consideration D) Environmental Assessment Statement cc Resident Inspector-Byron Resident Inspector-Draidwood L. N. 01shan-NRR S. P. Sands-NRR D. R. Muller-NRR Regional Administrator-RIII ,

M. C. Parker-IDNS I l I 1

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SUMMARY

OF PROPOSED CHANGE The proposed change involves l Technical Specification 5.3.2, which provides a description of the Rod Control Cluster Assemblies (RCCA). This-description states that "All Contiol Rods shall be hafclum, clad with stainless steel tubing". The proposed

' change would. allow for'the use of either hafnium or-silver, indium, cadmium (Ag-In-Cd) or.a combination of both of the absorber materials in the RCCAs. This change is required as a result of the recent concerns regarding swelling of RCCA's due to hydriding of the haf nium absorber material.

Hafnium and Ag-In-Cd RCCAs are interchangeable. The physical dimensions of the RCCAs are identical as are the materials of the spider. assembly and the rodlet cladding. The rod drop times and the rod worths for-the two absorber types are. equivalent. As additional assurance, both the rod drop times and rod worths are verified by testing during startup tests following each refueling outage. 'The use of Ag-In-Cd absorber material in RCCAs'is consistent with all assumptions of the transient and accident analyses. The RCCAs will meet the same mechanical, nuclear and thermal hydraulic limits as the original RCCAs. Since they are

. equivalent, a mixture of absorber types is permitted with no-adverse impact on plant safety.

A change very similar to this one has been approved for use at Callaway Fuclear Plant on February 14, 1989.

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AITAGRiERT__B PROPOSED CHANGES TO APPENDIX IECHNICAL SPECIFICATION OF FACILI*IY OPERATING LICENSES NPF-37,J1PF-66, NPF-72, AND NPF-77 Byron Hraidwond Revised Pages 5-4 5-4 i

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