ML20055E679

Responds to NRC Bulletin 88-008, Thermal Stresses in Piping Connected to Rcs. All Socket Welded Joints from Header Isolation motor-operated Valves to RCS for All 4 Loops Examined.No Recordable Indications Found

ML20055E679
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	07/06/1990
From:	Mroczka E CONNECTICUT YANKEE ATOMIC POWER CO., NORTHEAST UTILITIES
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
A07335, A07951, A7335, A7951, IEB-88-008, IEB-88-8, NUDOCS 9007120226
Download: ML20055E679 (4)

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(203) 665-5000 July 6,1990 Docket No. 50 213 A07335/A07951 1

Re: NRC Bulletin 88 08 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555

References:

(1 ) C. E. Rossi lettor to all Licensees, "NRC Bulletin No. 88 08: Thermal i

Stresses in Pipir,0 Connected to Reactor Coolant Systems," dated June 22, 408.

( 2 ) C. E. Rossi letter to all Licensees, *NRC Bulletin No. 88-08, Supplement 1:

Thermal Stresses in Piping Connected to Reactor Coolant Systems," dated June 24,1988.

(3) C. E. Rossl letter to all Licensees, *NRC Bulletin No. 88 08, Supplement 2:

Thermal Stresses in Piping Connected to Reactor Coolant Systems," dated August 4,1988.

( 4 ) E. J. Mroczka letter to USNRC, ' Response to NRC Bulletin No. 88 08,* dated September 20, 1988.

( 5 ) C. E. Rossi letter to all Licensees, *NRC Bulletin No. 88 08, Supplement 3:

Thermal Stresses in Piping Connected to Reactor Coolant Systems," dated April 11,1989.

( 6) E. J. Mroczka letter to USNRC, " Response to NRC Bulletin No. 88-08, Supplement 3," dated June 30,1989.

Gentlemen:

Haddam Neck Plant i

Response to NRC Bulletin No. 88-08 Thermal Stresses in Piolna Connected to Reactor Coolant Systems References (1), (2), and (3) requested Licensees to investigate their plants to determine if conditions which caused cracked piping at several units could exist elsewhere. Reference (4) responded to that request. Reference (5) similarly requested Licensees to determine if periodic 7 - **g 6f/h 90071202-6 900706 2

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A USNRC A07335/A07951/Page 2 July 6,1990 valve seat leakage through packing glands could result in unacceptable thermal stresses.

Reference (6) responded to that request.

Reference (4) Identified the four fill header connections to the Reactor Coolant System (RCS) loops as a potential concern. Reference (6) identified the residual heat removal isolation valves, the high pressure safety injection isolation valves and several drain header valves as potential concerns. In Reference (4), Connecticut Yankee Atomic Power Company (CYAPCo) committed to perform Non Destructive Examinations (NDE) of certain areas downstream of the fill header isolation valves. In Reference (6), CYAPCo committed to evaivate performing NDE on the RCS side of the above listed isolation valves if an inspectio:1 found them to have exhibited cacking leakage during operation.

All NDE (Ultrasonic Examination (UT) and visual inspection for leakege) has been corr plotsd. lists all areas examined by UT; no recordable Indications were found.

Reference (4) also committed to instrumenting the fill header lines. This has been done. Da'a from these thermocouples will be collected and analyzed during the upcoming cycle of operatlor,.

This completes Haddam Neck's reporting requirements for References (1), (2), (3), and (5).

Please contact us if you have any questions.

Very truly yours, CONNECTICLIT YANKEE ATOMIC POWER COMPANY FOR: E. J. Mroczka Senior Vice President BY:

C. F. Sears Vice President cc: T. T. Martin, Region I Administrator J. T. Shediosky, Senior Resident inspector, Haddam Neck Plant A. B. Wang, NRC Project Manager, Haddam Neck Plant i

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V USNC A07335/A07951/P0ge 3 July 6,1990 STATEOFCONNEC',10UT )

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Then persor.Eliy appeared before me as, C. F. Sears, who being duly sworn, did state that he is Vee President of Connecticut Yankee Atomic Power Company, Licensee herein, that he is authorized to cxecute and file the ferogoing information in the name and en behalf of the Licensee herein, and that the statements connirad in said information are true and correct to the best of his knowledge and bellef.

4,w D IlwEtdo e Notary Public 1

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Areas examined which resolve NRCB 88-08 concerns:

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- Fill Header Lines: All socket welded joints from the fill header isolation MOVs to the RCS for all four loops.

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HSPl injection: Valve to reducer (on RCS side of injection valve) welds on loops 1,2, and 4.

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RHR lsolation:. Valve to elbow (on RCS side of isolation valve) welds on suction and discharge of RHR to RCS' l

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