ML20083E035

Forwards Clarification to Re TMI Action Item II.E.4.2.5 on Containment Leakage Due to Seal Deterioration. Tech Spec Change Submitted

ML20083E035
Person / Time
Site:	Farley
Issue date:	12/20/1983
From:	Clayton F ALABAMA POWER CO.
To:	Varga S Office of Nuclear Reactor Regulation
References
TASK-2.E.4.2, TASK-TM NUDOCS 8312280417
Download: ML20083E035 (4)

Text

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. M lling Addrsss Alabama Power Company 600 North 18th Street Post Office Box 2641 Birmingham. Alabama 35291 Telephone 205 783-6081 F. L. Clayton, Jr.

Senior Vice President Flintridge Building AlabamaPower December 20, 1983 """""""**"**

Docket No. 50-364 Director, Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Attention: Mr. S. A. Varga Joseph M. Farley Nuclear Plant - Unit 2 Technical Specification 3/4.6.1.7 Gentlemen:

As required by the Joseph M. Farley Nuclear Plant Unit 2 Full Power License, NPF-8, paragraph 2.C.(17), Alabama Power Company provided a design description of a modified containment vent and purge system in letters dated September 30, 1981 and October 30, 1981. This design consisted of replacing the existing 18-inch containment mini-purge valves with 8-inch butterfly valves. Subsequent to physical installation of this design change, Alabama Power Company submitted on November 24, 1982 a request for a Technical Specification change to incorporate the installed 8-inch valves versus the removed 18-inch valves. As a result of questions raised by the NRC staff during review of this change, Alabama Power Company is providing the attached clarifications to information provided in our September 23, 1981 response to S. A. Varga letter on TMI Action Item II.E.4.2.5 dated August 5, 1981.

If there are any questions, please advise.

Yours very truly, o

F. L. Clayto , Jr.

FLCJ r/CLB:1 sh-d29 Attachment cc: Mr. R. A. Thomas f Mr. G. F. Trowbridge Mr. J. P. O'Reilly ,i& 1 Mr. E. A. Reeves Mr. W. H. Bradford

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Dr. I. L. Myers 8312280417 831220 Mr. F. Jape PDR ADOCK 05000364 p PDR L __ --- -- _ - - - - - - - . - -- - - - - - - - .

Attachment Outstanding NRC Issues Related to 8-inch Valve Operation Based upon telephone conversations with the NRC staff, the following comprise the open items from S. A. Varga's letter to F. L.

Clayton on TMI Action Item II.E.4.2.5 dated August 5,1981.

NRC Ites 1: Containment Leakage Due to Seal Deterioration Enclosure 1 of the above referenced NRC letter of August 5,1981 states that:

It is recommended that the following provision be added to the Technical Specifications for the leak testing of purge / vent line isolation valves;

" Leakage integrity tests shall be performed on the containment isolation valves with resilient material seals in (a) active purge / vent systems (i.e., those which may be operated during plant operating Modes 1 through 4) at least once every three months and (b) passive purge systems (i.e., those which must be administratively controlled closed during reactor operating Modes 1 through 4) at least once every six months."

APCo Response:

The above concern was fully discussed during the full power licensing of Farley Nuclear Plant Unit 2. The present leakage surveillance requirements for containment purge valves contained in Technical Specification 4.6.3.4 were agreed upon as a result of these discussions. This Technical Specification requires leakage testing

" prior to startup after each cold shutdown if not performed in the previous 3 months..." Alabama Power Company believes that this requirement adequately addresses the concern identified in the referenced NRC enclosure and that no further Technical Specification changes are required.

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Attachment to Alabara Pow:r Company's Decembsr 20, 1983 Letter;

Subject:

Technical Spzcification 3/4.6.1.7 Page 2 4

NRC Item 2: Conformance to Standard Review Plan Section 6.2.4, Revision 1 and Branch Technical Position CSB 6-4, Revision 1

Enclosure 2 of the above referenced NRC letter of August 5,1981 states that:

, Some purging / venting on current plants will be

pennitted provided that:

i a) purging is needed and justified for safety purposes, b) valves are judged by the staff to be both operable and reliable, and c) the estimated amount of radioactivity released during the time required to close the valve (s)

following a LOCA either i

i. does not cause the total dose to exceed the 10CFR Part 100 Guidelines; then a goal should be established which represents a limit on the annual hours of purging expected through each j particular valve, or

\ 11. causes the total dose to exceed the guideline i values; then purging / venting shall be limited j to 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> / year.

APCo Response:  !

Alabama Power Company operates the 8-inch purge system continuously in order to preclude excessive containnant pressurization and to i

minimize the buildup of containment radiation levels. As documented in Enclosure 3 of the referenced NRC August 5,1981 letter, installation of

! the continuously operating 8-inch system (in lieu of a 3-inch vent with periodic cperation 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> / year of the 18-inch vent) provides I enhanced safety while allowing for "immediate personnel entry into containment for safety related maintenance or surveillance activities."

The design of the 8-inch system was submitted to the NRC on September ,

30, 1981 and supplemented on October 30, 1981 as required by Farley Unit 2 license condition 2.C.(17). This design does not include the capability for automatic periodic cycling of the 8-inch purge system.

The 8-inch valves were not procured for cycling service. They were procured to be open continuously with high speed closure upon receipt of containment isolation signal. If the purge system were modified to allow cyclic operation of the 8-inch valve (which would be a significant modification involving additional cable pulls, containment penetration, logic changes, main control board changes, etc. at considerable  !

Attachment to Alabama Pow:r Company's Decemb:;r 20, 1983 Letter;

Subject:

Tcchnical Sp;cification 3/4.6.1.7 Page 3 expense), the valves would have to change position approximately 2000 times per 18 month fuel cycle. This is based upon automatic actuation of the purge system at a containment pressure of 0.25 psig which is necessary to preclude damage to the purge system ductwork (Ref: F. L.

Clayton to A. Schwencer letter dated January 15,1980). This large number of operations could decrease the life of valve and valve seat and could potentially degrade the 'bility of the valve to perform its safety-related function. Based on the above plant-specific conditions, Alabama Power Company believes the present operational mode of the 8-inch purge system, on a continuous basis, is the only feasible approach to comply with the goals of the referenced NRC letter, Enclosure 2.

NRC Item 3: Recommended Technical Specifications Enclosure 6 (Sample Containment Ventilation Technical Specifications) of the above referenced HRC letter of August 5,1981 contains the following items not currently included in the Farley Unit 2 Technical Specifications, a) Purging for safety related reasons only.

b) Locked closure of the main purge valves.

c) Leak test frequency of the purge valves.

APCo Response:

Alabama Power Company discussed the requirements for purging in Item 2 above. In addition, the draft Technical Specification 3/4.6.1.7 specifies that the purge supply and exhaust isolation valves be locked closed. Alabama Power Company currently maintains the purge valves (48-inch) in a closed position. These valves are air-operated with air supply required to open the valves. The electrical breakers to the air supply solenoid valves are tagged out in Modes 1 through 4. The plant manager's permission is required to remove the tag and provide air to the operator. Only after this action can the valves be operated. The closed valve position is verified every 31 days. Alabama Power Company

believes this provides at least equivalent protection to a locked valve and is more desirable from a control and operations viewpoint. Finally, draft Technical Specification 4.6.3.4 is addressed in Item 1 above.

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