ML20082E614

Application for Amend to License NPF-3,revising Tech Spec Section 4.5.2.d & Table 3.3-10 Re Removing 480-volt Ac Power from DHR Isolation Valves During Modes 1,2 & 3 When Valves Closed

ML20082E614
Person / Time
Site:	Davis Besse
Issue date:	11/21/1983
From:	Crouse R TOLEDO EDISON CO.
To:
Shared Package
ML20082E602	List: ML20082E599 ML20082E614 ML20082E618
References
TAC-53297, TAC-53298, NUDOCS 8311280256
Download: ML20082E614 (4)

Text

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s APPLICATION FOR AMENDMEN'T TO FACILITY OPERATING LICENSE NO. NPF-3 FOR DAVIS-BESSE NUCLEAR POWER, STATION UNIT NO. 1 Enclosed are forty-three (43) copies of the requested changes to the Davis-Besse Nuclear Power Station Unit No. I Facility Operating License No. NPF-3, together with the Safety Evaluation for the requested change.

The proposed changes include:

1. Section 4.5.2.d

2. Table 3.3-10 i

By /s/ R. P. Crouse Vice President, Nuclear l

.a l-Sworn and subscribed before me this 21st day of November, 1983.

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l l

Laurie A. Hinkle, nee (Brudzinski)

Notary Public, State of Ohio My Commission Expires May 16, 1986 i

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8311280256 831121 PDR ADOCK 05000346 SEAL P ,

.PDR l =

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e Docket No. 50-346 License No. NPF-3 Serial No. 997 November 21, 1983 Attachment I. Changes to Davis-Besse Nuclear Power Fcation Unit 1, Appendix A Technical Specifications Section 4.5.2.d.

A. Time required to Implement . This change is to be effective upon NRC approval.

B. Reason for Change (Facility Change Request 83-124).

To comply with a request from Mr. D. G. Eisenhut dated September 23, 1983, (Log No. 1375) concerning Restart of Davis-Besse Nuclear Power Station, Unit 1. Contained in the safety evaluation, Section 2.11 high/ low pressure interface, was a request to remove power from DH-11 and or DH-12. To comply with this request the attached. amendment request is required.

C. Safety Evaluation (See Attached)

D. Significant Hazard Consideration (See Attached)

SAFETY EVALUATION i

i This amendment request is to revise the Technical Specification to remove )

the 480 VAC power from the Decay Heat Removal (DHR) isolation valves DH-11 i and DH-12 during Modes 1, 2, 3 when the valves are closed. " ace safety function of DHR isolation valves DH-11 and DH-12 is to isolate the Reactor Coolant System (RCS) from the Decay Heat (DH) system when the RCS pressure is greater than the pressure rating of the DH system.

The present technical specification (4.5.2.d.1) require valves DH-11 and DH-12 to automatically close when the RCS pressure exceeds the set points of either valve and the valve is open.

The Safety Evaluation Report contained within the NRC letter dated September 23, 1983 (Log No. 1375) required Toledo Edison to remove 480 VAC power from either DH-11 or DH-12 in Modes 1, 2 and 3 when these valves are closed and the RCS pressure is higher than the DH system pressure rating.

The removal of 480 VAC power will disable the automatic closure signals to DH-11 and P:t-12 and could also be interpretted as to place the plant in an action statement, since the interlock will be inoperable. The amendment is to remove this requirement that the interlock for these valves be operable when these valves are closed and 480 VAC power is disconnected.

The valves (DH-11 and DH-12) could be inadvertently open if the 480 VAC power is on and there is a fire in the control room or they could be manually opened from the pit location inside the containment vessel which requires an effort to gain access. With 480 VAC power disconnected from these valves there is no practical way that they can open, and therefore, the interlocks are not needed.

Therefore, this is not an unreviewed safety question.

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SIGNIFICANT HAZARD CONSIDERATION The proposed amendment request does not contain a nignificant hazard. The request is to remove the requirement to have the interlock on DH-11 and/or

-DH-12 (decay heat pressure interface between the reactor coolant and decay heat systems) if the valves are closed and the 480 VAC power is disconnected from its motor operators. This request is submitted as identified in the Safety Evaluation Report Davis-Besse Nuclear Power Statoin Fire Protection Program Corrective Action Plan (SER).

The SER Section 2.11 High/ Low Pressure Interfaces identified the potential for a fire in the control room to disable the pressure interlock and open both valves resulting in a LOCA outside of containment. By removing power when the valves are closed and the RCS pressure is greater than the Decay Heat system pressure rating the potential for inadvertent actuation of the valves is removed if there is a fire in the control room. The interlock for the valves are not affected by this request as the power is only removed from the valves.

The valve position indication (VPI) is unaffected by removal of the power from the motor operators. The VPI is supplied from a separate power source. Also, the valves could be opened manually from inside containment but due to their location in a non-LOCA type environment this is an unlikely event. The area is only accessible when the plant is shutdown and the hatch must be unbolted and removed to gain access to the valves.

The Commission has provided guidance concerning the application of the standards in 10 CFR 50.92 by providing certain examples (48 FR 14870).

One of the examples of actions involving no significant hazards considerations relates to a change that constitutes an additional limitation, restriction or control not presently included in the technical specifications.

The above amendment request is an additional restriction by requiring power removed from valves DH-11 and or DH-12 in Modes 1, 2 or 3 when the valves are closed and the RCS pressure is higher than the Decay Heat System pressure rating.

Therefore, based on the above and the attached safety evaluation this is not a Significant Hazard.

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