ML18052A749

Application for Amend to License DPR-20,revising Tech Specs to Reflect Removal of Containment Air Cooler Fan V4A

ML18052A749
Person / Time
Site:	Palisades
Issue date:	10/20/1986
From:	Buckman F CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
Shared Package
ML17216A841	List: ML18052A748 ML18052A749
References
NUDOCS 8610270456
Download: ML18052A749 (4)

Text

I 'i CONSUMERS POWER COMPANY Docket 50-255 Request for Change to the Technical Specifications License DPR-20 For the reasons hereinafter set forth~ it is requested that the Technical Specifications contained in the Provisional Opera.ting License DPR-20, Docket 50-255, issued to Consumers Power Company on Octob~r I6, I972, for the Palisades Plant be changed as described in Section I below:

I. Changes A. In section 3.4.Ib. delete "Containment Air Cooler V4A" B. Revise Basis section 3.4 as follows:

"Basis An emergency diesel generator is connected to each of the two engineered safeguards 2400-volt buses. Redundant equipment is connected to each of the two buses to assure that equipment 'is available under all conditions for minimum containment cooling, and minimum safety injection. If a piece of equipment is inoperable, it is intended it be returned to service promptly after repairs have been completed or action will be taken to place the reactor in a shutdown condition.

The original FSAR analysis of the post-accident containment response determined that a 42" double-ended rupture of the primary coolant piping was the most limiting break with.respect to the in-containment response. It was determined by analysis that three containment air coolers or two containment spray pumps could provide sufficient cooling to' 'limit containment pressure to less than the design condition. The three air coolers, fed from bus ID and associated with diesel generator I-2 were therefore considered redundant to the two spray pumps, on bus IC associated with diesel generator I-I. Additional excess containment cooling was provided with one spray pump on the ID bus included with the three air coolers on that bus and one air cooler fed from bus IC included with the two spray pumps on that bus. The LOCA analysis did not consider the use of either of these excess pieces of equipment.

In I 9.80, as reported in LER 80-003, reanalysis of the Palisades Main Steam Line Break Event resulted from a determination that the containment spray initiation time was longer than had been assumed in the FSAR analysis. Peak containment pressure for a MSLB is mitigated by the actuation of the containment sprays whereas for a LOCA the peak pressure is initially limited by the heat sinks in containment. It was determined in the reanalysis that the peak containment pressure during a MSLB is not mitigated by the use of the three containment air coolers. However, the pressure could be maintained below the design of 55 psig with: the single available TSOPI086-0I44-NL04 ( '* 0610270456 061020 I

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2 containment spray pump on the same bus as the three air coolers.

For the MSLB the redundant containment cooling equipment are the containment spray pumps associated w~th both diesel generators."

C. In section 5.2.3a revise second sentence as follows:

"Three units, with a total cooling water flow of 4875 gpm and with an inlet temperature *** "

II. Discussion The above proposed Technical Specifications changes are requested because containment air cooler for V4A, which is characterized as providing reserve cooling capacity, will not be operable during conditions which initiate an SIS signal. Ample containment air cooling, in the event of a DBA, is provided on the 1-1 diesel generator by the two containment spray pumps without the operability need of V4A. No credit has been taken for the operability of V4A in any accident analysis.

The basis for section 3.4 has been totally revised to be consistent with the removal of the V4A containment air cooler, to correct several errors and inconsistencies that existed in the basis and to delete statements that three containment air coolers are redundant to two containment spray pumps. Actions taken to resolve issues described in LER 86-003.,

dated April 3, 1980, in which analysis was done for a main steam line break and showed that the cooling effect of the containment air coolers for this event were not equivalent nor redundant to the containment spray pumps and furthermore the cooling capacity of the one containment spray pump on the 1-2 diesel bus is sufficient in an MSLB to provide containment cooling.

The modfied basis describes the link of the applicable analysis to the containment cooling system.

The proposed change in section 5.2.3a. corrects an erroneous statement that each containment air cooler has 4875 gpm of cooling water flow.

The correct statement is a total cooling water flow of 4875 gpm for three coolers as stated in the updated FSAR section 6.3 table 6-10.

Analysis of No Significant Hazards Consideration The changes do not involve a significant hazards consideration as discussed below:

The FSAR Containment Pressure Analysis considers the VHX-4 air cooler and associated fan V4A to be excess equipment and is not considered necessary to mitigate the containment pressure. For Loss of Coolant Accidents the FSAR considers the 3-containment air coolers on the 1-2 diesel generator to be redundant to the 2-containment spray pumps on diesel generator 1-1. MSLB analysis resulting from LER 80-003 has shown the I-containment spray pump on the 1-2 D/G is ample to prevent containment overpressurization. Sufficient cooling capacity exists on the 1-1 D/G with the two containment spray pumps to mitigate the overpressurization following either a MSLB or LOCA. The VHX-4 air TSOP1086-0144-NL04

3 cooler and associated equipment have not been considered in either accident analysis nor any others.

Therefore, although removal of the air cooler reduces the available containment cooling capacity, removing it as required operable equipment does not increase the probability of, or consequences of, an accident or malfunction of equipment.

Removal of the V4A containment air cooler, which is not considered in the accident analysis and therefore is only excess capacity for containment cooling, does not create an accident or malfunction of a different type than previously evaluated. Containment cooling as determined by the accident analysis is still adequate to keep the containment within the design parameter.

Although the V4A containment air cooler provides excess*margin to the containment cooling function, no credit was taken for its operation in either Fhe FSAR Containment Analysis which considered a LOCA or in the MSLB Analysis which was discussed in LER 80-03. The additional margin provided by this excess cooling capacity was not considered in determining the margin between the analyzed containment response and containment response and containment design conditions. Therefore the margin of safety as defined in the basis for the Technical Specifications has not been reduced.

The editorial change in section 5.2.3a corrects an error in the statement concerning the service water flow to the containment air coolers. The correct statement can be found in FSAR section 6.3 table 6-10. This editorial correction does not increase the probability or consequences of an accident or malfunction of equipment nor does it create an accident or malfunction of equipment nor does it create an acc~dent or malfunction of a different type than previously evaluated.

Furthermore, it does not reduce the margin of safety as defined in the basis for the Technical Specifications.

III. Conclusion The Palisades Plant Review Committee has reviewed this Technical Specification Change Request and has determined that this change does not involve an unreviewed safety question and therefore involves no significant hazards consideration. This change has also been reviewed under the cognizance of the Nuclear Safety Board. A copy of this Technical Specification Change Request*has been sent to the State of Michigan official designated to receive such Amendments to the Operating License.

TSOP1086-0144-NL04

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4 CONSUMERS POWER COMPANY

• • .~.~ Nuclear Operations Sworn and subscribed to before me this 20th day of October 1986.

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Elaine E Buehrer, Notary Public Jackson County, Michigan My commission expires October 31, 1989 TSOP1086-0144-NL04