ML20099E640

Forwards Rev 1 to Reactor Vessel Cavity Seal Test Results, in Response to IE Bulletin 84-03.Rept Concludes than Min Acceptance Criteria Re Seal Capacity Met & Seal Mod Not Required

ML20099E640
Person / Time
Site:	Mcguire, Catawba, McGuire, 05000000
Issue date:	02/18/1985
From:	Tucker H DUKE POWER CO.
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20099E643	List: ML20099E640 ML20099E656
References
IEB-84-03, IEB-84-3, NUDOCS 8503140061
Download: ML20099E640 (2)

Text

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DUKE POWER GoxPm P.O. nox 33180 GHAHl,OTrE, N.C. 28242

!!AL 11. TUCKER TELEPHONE vu,a Pmannormt n" g e (704) 373-4531 NtTLEAR PeoptTTION '

'f 4 February 18, 1985 l

l Dr. J. Nelson Grace, Regional Administrator U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 l Atlanta, Georgia 30323 l

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Subject:

McGuire Nuclear Station l Catawba Nuclear Station l Docket Nos. 50-369 and 50-370; 50-413 and 50-414 l NRC/0IE Bulletin 84-03

Dear Dr. Grace:

Mr. R. C. DeYoung's (NRC/0IE) letter dated August 24, 1984 transmitted NRC/01E Bulletin 84-03 which concerned an incident in which the refueling cavity water seal failed and rapidly drained the refueling cavity, and requested certain actions to assure that fuel uncovery during refueling remains an unlikely event.

My letter of November 21, 1984 submitted Duke Power Company's response

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to this bulletin for the McGuire and Catawba Nuclear Power Stations l which provided a summary of our evaluation of the potential for and consequences of a refueling cavity water seal failure for the McGuire and Catawba Nuclear Stations. Although the original seal was designed and tested by the manufacturer establishing the adequacy of the seal configuration, our response indicated that a reevaluation of the seal integrity would be conducted via subjecting the seal configuration used at McGuire and Catawba to a series of tests designed to determine the ultimate capacity of the seals (if the minimum acceptance criteria is not met on any test the seal was to be modified as necessary to obtain the required capacity). This testing was performed December 17-21, 1984 (as documented in my December 31, 1984 letter), and the test results report submitted by my letter dated January 18, 1985. Based on Unitan evaluation of the test results, it was concluded that McGuire 1 and Catawba Unit 1 meet the minimum acceptance criteria with regard to seal capacity, and seal modifications are not required.

It was stated that McGuire Unit 2 as-built dimensions would be re-corded during the Cycle 2 refueling outage (which began January 25, 1985), and evaluated against the test results and compared to the minimum acceptance criteria (Catawba Unit 2 is under construction).

The as-built test data reportiswas to be revised and resubmitted when the remaining recorded and subsequent evaluations completed for g3140061850218 O ADOCK 05000369 PDR

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Dr. J. Nelson Grace, Regional Administrator February 18, 1985 Page 2 McGuire Unit 2 and Catawba Unit 2. In addition, in response to NRC concern for the adverse effect of a dropped assembly on the pressray seal, an evaluation of the potential for a dropped fuel assembly to damage the cavity seal was performed by Duke (reference my January 29, 1985 letter) which determined that no hardware changes are required.

Please find attached a revised copy of the Reactor Vessel Cavity Seal Test report. This revision incorporates the evaluation of the McGuire 2 as-built dimensions and concludes that McGuire Unit 2 meets the minimum acceptance criteria with regard to seal capacity, and seal modification is not required. The test report will be revised and resubmitted when the remaining as-built data is recorded and subsequent evaluations completed (to determine the adequacy of the seal or if modifications, and therefore further testing, is required) for Catawba Unit 2. Duke is committed to maintain the minimum acceptance criteria of a seal capacity to withstand twice the normal static head of water.

Please advise if there are any questions or if further information is required.

I declare under penalty of perjury that the statements set forth herein are true and correct to the best of my knowledge.

Very truly yours, h,b. OY ,q Q Hal B. Tucker PBN:smh Attachment cc: Mr. R. C. DeYoung, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. W. T. Orders NRC Resident Inspector McGuire Nuclear Station P. K. VanDoorn NRC Resident Inspector Catawba Nuclear Station k