A06107, Submits Addl Info Re 10CFR50,App J Integrated Leak Rate Testing Conducted During Fall 1986 Refueling Outage,Per NRC .Preventative Maint Program for Fisher Butterfly Containment Isolation Valves Initiated

Submits Addl Info Re 10CFR50,App J Integrated Leak Rate Testing Conducted During Fall 1986 Refueling Outage,Per NRC .Preventative Maint Program for Fisher Butterfly Containment Isolation Valves Initiated

ML20212J113
Person / Time
Site:	Millstone
Issue date:	01/16/1987
From:	Mroczka E, Sears C NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	NRC OFFICE OF ADMINISTRATION (ADM)
References
A06107, A6107, TAC-60646, NUDOCS 8701280088
Download: ML20212J113 (2)

Text

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General Offices

• Selden Street, Berhn, Connecticat sI s5sNw- ~ P.O. BOX 270

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HARTFORD. CONNECTICUT 06141-0270 L L J C Z'*l' C ,"w*.", (203) e 50 w January 16,1987 Docket No. 50-336 A06107 Re: 10CFR50 Appendix 3 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Gentlemen:

Millstone Nuclear Power Station, Unit No. 2 Additional Information 10CFR50 Appendix 3 Testing in a letter dated November 6,1985(l), Northeast Nuclear Energy Company (NNECO) submitted to the NRC Staff a schedule for performance of the next three Type "A" Integrated Leak Rate Tests (ILRT) for the Millstone Unit No. 2 containment building pursuant to 10CFR50, Appendix 3, Section Ill.A.6(a).

Addi ional information was forwarded to the Staff in a letter dated June 18, 1936 2),

In a letter dated September 23, 1986(3), the Staff issued a Safety Evaluation

• which concurred with the ILRT schedule outlined in Reference (1) contingent upon NNECO providing the Staff with additional information relative to the 10CFR50 Appendix 3 testing conducted during the Fall,1986 refueling outage at Millstone Unit No. 2. The following information is provided in response to the Reference (3) request:

1) A preventative maintenance program for the Fisher butterfly containment isolation valves has been initiated to facilitate the replacement of each "T-ring" seat every other outage. During the Fall 1986 outage, all of the subject Fisher butterfly containment isolation valves had a new "T-ring" seat installed. At the next refueling outage, one half of these valves will have a new "T-ring" (1) 3. F. Opeka letter to E. 3. Butcher, " Scheduling ot Type A Integrated Leakage Rate Tests," dated November 6,1985.

(2) 3. F. Opeka letter to A. C. Thadani, "10CFR50 Appendix 3 Testing," dated June 18,1986.

(3) A. C. Thadani letter to 3. F. Opeka, dated September 23,1986. y 01 8701280088 870116 PDR ADOCK 05000336 I PDR _

7 seat installed. At the following refueling outage, the remaining valves will have a new "T-ring" installed. This program will ensure that each valve will have its "T-ring" seat replaced every other outage. .Where practical, the "T-ring" seats will be replaced such that for two valves in series, one of the two valves will have its seat replaced each outage.

2) During thel Fall 1986 outage, screens were installed in the containment trenches (at the -22' elevation) that lead to the normal containment sump. This will prevent debris from entering the sump pump discharge _ piping and ultimately becoming lodged under the containment isolation valve seat.

3) During the Fall 1986 outage, Local Leak Rate Testing _(LLRT) was performed on.all containment isolation valves that are subject to Type "C" testing, including those previously identified as " problem -

valves."

4) The _ results of the LLRT conducted during the Fall,1986 refueling outage were reported to the NRC's Region I Staff in a telephone conversation on November 4,1986 and during a Region I inspection of the site from December 2,1986 through December 5,1986.

We trust that the above information is satisfactory.

Very truly yours, NORTHEAST NUCLEAR ENERGY COMPANY t.h A fh.

E. J. Mroczka '*

Senior Vice President By: C. F. Sears Vice President cc: Thomas E. Murley, Administrator, Region 1 T. Rebelowski, Senior Resident inspector D. H. Jaffe, Licensing Project Manager