NLS8900045, Forwards Rev to Proposed Change 31 to Tech Specs Containment Purge & Vent Valves.Proposed Change Incorporates All Amends to License DPR-46 Through Amend 126

Forwards Rev to Proposed Change 31 to Tech Specs Containment Purge & Vent Valves.Proposed Change Incorporates All Amends to License DPR-46 Through Amend 126

ML20245A306
Person / Time
Site:	Cooper
Issue date:	04/19/1989
From:	Kuncl L NEBRASKA PUBLIC POWER DISTRICT
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20245A309	List: ML20245A312 NLS8900045, Forwards Rev to Proposed Change 31 to Tech Specs Containment Purge & Vent Valves.Proposed Change Incorporates All Amends to License DPR-46 Through Amend 126
References
NLS8900045, NUDOCS 8904250136
Download: ML20245A306 (6)

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}' b . GENERAL OFFICE Nebraska Public Power' District "" "%&#O#fdif0^!a"*"

6 i NLS8900045 April 19, 1989 e

. Nuclear Regulatory Commission Document Control Desk' Washington,!DC.20555

Reference:

Letter, H. G. Parris (NPPD) to USNRC dated April 19, 1988, " Proposed Change No. 31 to- Technical Specifications -

Cooper Nuclear Station" Subject- Revision to Proposed Change No. 31 to Technical

. Specifications Containment Purge and Vent Valves.- Cooper Nuclear Station NRC Docket No. 50-298, DPR-46 Gentlemen:

In the above reference, Nebraska Public Power requested

'a change to the Cooper Nuclear Station Technical Specifications concerning the Containment Purge and Vent Valves. The District requests to revise the proposed change to incorporate various comments identified during NRC review.

A discussion and the applicable revised Technical-Specification pages are contained in the attachment. The modification to the Technical Specifications within this proposed change has been evaluated with respect to the requirements of 10CFR50.92. The results of the evaluation are included in the attachment.

By copy of this letter and the attachment the appropriate State of Nebraska Official is being notified in accordance with 10CFR50.91(b).

This proposed change incorporates all amendments to the CNS Facility Operating License through Amendment 126 issued November 7, 1988. This change has been reviewed by the necessary Safety Review Committees.

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Pago'2 April 19, 1989 In addition to the signed original, 37 copies of this submittal are also submitted for your use. Copies to the NRC Region IV Office and the CNS Resident Inspector are also being sent in accordance with 10CFR50.4 (b) (2) .

Sinc ely, L. G. uncl Nuclear Power Group Manager LGK/GRS:KM2-1(CHNG31)

Attachment cc: H. R. Borchert  !

Department of Health i State of Nebraska NRC Regional Office Region IV Arlington, TX NRC Resident Inspector Cooper. Nuclear Station

Paga 3 April 19, 1989 STATE OF NEBRASKA)

. )ss PLATTE COUNTY )

L. G. Kuncl, being first duly sworn, deposes and says that he is an authorized representative of the Nebraska

' Public Power District, a public corporation and political subdivision of the State of Nebraska; that he is duly authorized to submit this request on behalf of Nebraska Public Power-District; and that the statements contained

'herein are true to the best of his knowledge and belief.

p. G. Kuncl Subgeribed in my presenge and sworn to before me this

/ h day of _ [ln;@ , 1989.

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NOTARY fUBI/IC matannatem==

COLLEEN M. KUTA Ny Coast ES Ass 4.120 l

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. 1 Attachment 1 Revised Technical Specifications for Containment Vent and Purge Valves Revised Pages: 160 173 174 175 179 ,

184  !

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Reference:

Letter from H. G. Parris to USNRC dated April- 19, 1988, " Proposed Change No. 31 to Technical Specifications - Cooper Nuclear Station" Nebraska Public Power District submitted the above reference as part of the final close out of Multiplant Action Item B-24," Venting and Purging Containment while at Full Power and Effect of LOCA" for Cooper Nuclear Station (CNS). ' Subsequent NRC review identified several comments that needed to be addressed prior to closing out B-24 for CNS. 'Accordingly, the District is revising the submittal to address these comments. These proposed Technical Specification changes revise those contained in the reference and are listed as follows:

1. The Existing Technical Specification 3.7. A.2 on Containment Integrity has been redesignated as 3.7.A.2.a. Specification 3.7.A,2.b hat 'een > added to page 160 to limit operation of the drywell and suppression chamber purge and vent system when coolant temperature is greater than 212*F. The new specification will limit operation of the drywell and suppression chamber purge and vent system with coolant temperature above 212'F to 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> per cale6dar year with the' 24-inch isolation valves in one supply line and one exhaust line open for containment inerting, deinerting, or pressure control. A footnote at the bottom of the page indicates the specification does not apply for certain venting operations that utilize the 2-inch bypass line(s) around the closed applicable inboard purge exhaust isolation valve (s).

2. A note has been added to Table 3.7.4 on page 175 to require a functional verification, once per operating cycle, of the blocking devices that limit the maximum opening angle to 60* for designated valves.

3. The Bases for Sections 3.7 A and 4.7. A have been supplemented on page 179 to include a discussion on the new specification 3.7.A.2.b.

4. The Bases for Sections 3.7.D and 4.7.D have been supplemented on page 184 to include a discussion on the.new note to Table 3.7.4.

Evaluation of this Revision with Respect to 10CFR50.92 l

The enclosed Technical Specification change is judged to involve no significant hazards based upon the following:

1. Does the proposed license amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

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Evaluation:

The'previously evaluated accident under consideration here is the Loss of Coolant Design Basis Accident discussed in S,ection XIV uf the CNS Updated

- Safety Analysis Report. This amendment request deals with the vent and purge containment isolation valves and conduct of vent / purge operations when coolant temperature is >212*F. This . affects containment integrity and the fission product release to the secondary containment in the above-mentioned accident, The proposed amendment places additional restrictions and limitations on the operation of the drywell and suppression purge and vent system, in particular, the amount of time the 24-inch containment purge and vent isolation valves can be open in a calendar year and the use of only 2ne supply and one exhaust line. Additional operability restrictions are placed on the Standby Gas Treatment Systems as well.

The proposed amendment conforms to guidance given in Branch' Technical Position CSB 6.-4, " Containment Purging During Normal Plant Operation."

The proposed amendment does not involve any hardware modifications or allow any plant operations that will increase the probability of the Design Basis Loss of Coolant Accident (LOCA). The proposed amendment will decrease the consequences of this accident by:

a. Restricting the use of the drywell and suppression chamber purge and vent system through the 24-inch containment isolation valves when coolant temperatures are above 212*F. This reduces the probability of a LOCA occurring with the 24-inch valves open and thus relying

. on the valve operators to function properly to maintain primary containment integrity. This also decreases the probability of a LOCA damaging a Standby Cas Treatment (SBGT) System that might be in the flow path due to excessive differential pressure across its filter units. Also, the other SBGT system is required to be operational at the time and not to be used in purge / vent operation. These additional requirements will better ensure at least one SBGT System is available to mitigate the fission product activity released to the environs as assumed in the previously evaluated accident.

b. Requiring that once every cycle the devices which limit the maximum opening angle to 60' for the m'otor operated isolation valves are verified to be functional. With these blocking devices in place, analysis shows that the valves can close against an expected LOCA pressure profile within the time specified in Technical Specifications and, hence, perform their isolation function. Without these blocking devices, there is no assurance the designated valves could shut against LOCA forces.

Based on the above, the proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated.

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2. Does the proposed license amendment create the possibility for a new or different kind of accident from any accident previously evaluated?

, Evaluation:

The proposed amendment places additional restrictions on vent / purging operations and the vent / purge isolation valves as described above and does not permit any new mode of operation that would create the possibility for a new of different kind of accident from any previously evaluated.

3. Does the proposed amendment involve a significant reduction in the margin of safety?

Evaluation:

The proposed amendment places additional restrictions on plant components and operations to better ensure primary containment integrity. It does not affect any operating limits or trip setpoints so there is no change in the margin of safety.

4. Additional basis for proposed no significant hazatds consideration determination:

The commission has provided guidance concerning the application of the standards for determining whether a significant hazards consideration exists by providing certain examples (48CFR14870).

The examples include: "(ii) A change that constitutes an additional limitation, restriction, or control not presently included in the Technical Specifications. .. " It is the District's belief that the proposed change is encompassed by the above example.