ML20065K104

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Forwards Schedule for Implementing Recommendations in 901003 Safety Evaluation Re Loss of All Ac Alternating Current Power
ML20065K104
Person / Time
Site: Point Beach  NextEra Energy icon.png
Issue date: 11/08/1990
From: Fay C
WISCONSIN ELECTRIC POWER CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
CON-NRC-90-110 VPNPD-90-459, NUDOCS 9011150161
Download: ML20065K104 (5)


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231 W Michgan. Ro. Box 2046, MAmukee.WI 53201 (414)221 2345 J VPNPD-90-459 NRC-90-110 November 8, 1990 Document Control Desk 10-CFRL50.63;

'U.S. NUCLEAR-REGULATORY COMMISSION Mail Station P1-137 Washington, D.C. 20555 Gentlemen: '

DOCKET NOS. 50-266 AND 50-301 10=CPR 50.63'. TAC. NOS. 68586 AND 68587 LOSS OF ALL ALTERNATING CURRENT POWER-

' POINT BEACH NUCLEAR PLANT. UNITS 1'AND 2-On October 9, 1990,--Wisconsin-Electric received--thecSafety.

Evaluation by the Nuclear Regulatory Commission Office 4of Nuclear . .

Reactor Regulation for.the-Point Beach Response to the1 Station Blackout' Rule, 10 CFR'50.63'.' The-Safety Evaluation was transmitted to Wisconsin Electric-by a= letter.from; Robert:B.-Samworth of-the-NRC to C. W. Fay of-Wisconsin Electric, dated: October;3,:1990.1 The October'3, 1990, letter 1 concludes"that the1 design'and' proposed method offdealing with a station. blackout at'the Point' Beach

-Nuclear Plant is,in conformance with!the rule,f10:CFR150.63.- Thi's-finding is contingent.upon WisconsinIElectric: notifying the NRC that the recommendations'.in the1 Safety.Evaluationiwill be:

implemented. The notification'and.schedulerfor7 implementation..of1 these recommendations is'provided1in"thelattachments.to this letter..

Recommended clarifications $of)the Sa'fety: Evaluation; Report and the Technical. Evaluation Report aretalsoiprovidedJin!the4 attachment.- -

We would be pleased to answer.anyDquestions/regarding>this: letter-or the implementation.of-10iCFR~50.63'requirementshat>the: Point' Beach Nuclear ~ Plant. , , ,o- '

-Very,tru y yours,_

'6-f7 C...W. Fay Vic'e P$esident:

. Nuclear-' Power.

CopiesTto?NRC' Regional'Aaministrator, RegionsIII

( NRCEResident. Inspector.: ' '

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Wisconsin Electric Rvaluation of the Safety Evaluation by the Office of Nuclear Reactor Regulation- l Related'to Station Blackout Point Beach Nuclear Plant, Units 1 and 2 Evaluation of NRC Recommendations:

The Proposed Ahc Power Source NRC Recommendation: The licensee should demonstrate using; actual test data that the Gas Turbine Generator-(GTG)_can.obtain and a maintain a reliability of 0.95 or better. . This demonstration:

should-be completed within a reasonable-time period (approximately 2 years). If the demonstration does not indicate an acceptable reliability of.0.95 or better, the licensee /should:

propose an alternative or install another AAC' source to; meet;the. . 1 guidelines of RG 1.155 and NUMARC 87-00. -(By; letter dated' August-3, 1990 WEPCO advised NRC.that two additional EDGs'wouldibe' installed. That letter did not indicate how the installationL <

would relate to planning for station blackout.):

The licensee should also complete the test to show that the AAC-source (GTG) can power the SBO loads within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> after the .

onset of the SBO.

WEPCO Resoonse: Wisconsin Electric will demonstrate the . 3 achievability of 95% reliability,on the GTG,.using. actual" test data, within 2 years. In a letter dated June _29, 1990, Wisconsin'.

Electric provided information to-the NRCfregarding!the status of  ;

testing-of the GTG as an AAC power for Point Beach. : Subsequent '

L testing has shown that the high' temperature trip'of the auxiliary j power diesel generator for the GTG can still occuriif'outside o temperatures are higher than'the temperatures experienced-during the June 15, 1990 test. The'outside air temperature at: Point -

Beach during the June 15 test was approximately.55'F. .

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The manufacturer of the auxiliary, power diesel generator was consulted. The manufacturer recommended'replacementEof:the high  :

l temperature trip circuitry. This modification isiexpectedcto-be complete by May 1991. The successful resolution of:the'high

  • temperature trip. problem by this modificationiwill not'be completely verified-until;an eight' hour durationitestLis performed with warmer outside air temperatures'-(l'.~e. during the1 summer of.11991). Blackout start testing of the GTG is. continuing; on a monthly basis to establish the datauto determino its ,

L reliability in this mode.

  • When blackout start tests are performed on the GTG, it is normally' started and. loaded within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. WisconsinEElectric:

believes that this adequately shows that the AACisource (GTG).can power SBO loads within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> -after the onset of' the 'SBO.

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Condensate Inventory for Decay Heat Removal NRC Recommendation: The licensee should revise the.TS.to specify a minimum condensate tank inventory of 13,000 gallons per unit to  ;

provide assuranue that adequate water is available to cope with i an SBO for the required 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> duration.

I WEPCO Response: The SER states that this recommendation is based l on the reasons discussed in the SAIC TER that is attached to the i SER. The SAIC TZR states:

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Tf the NUMARC coping calculation of Section 7.2.1 (8) were typlied directly, the required condensate inventory for one I hour would be just under 13,000 gallons. If 13,000-gallons j were available-in the CST, the SG' Water inventory _would )'

provide the margin necessary to shift suction during the recovery from SBO.

The method for determining required condenmate inventory provided in NUMARC 87-00, Section 7.2.1, is. based on a coping duration lof four (4) hours. This methodology is not directly applicable to Point Beach because the AAC power source, which is'available within one hour, will be used to provide power to the Service Water pumps. Service water can'be used as a suction source for s the Auxiliary Feedwater system. i Due to the inapplicability of the NUMARC methodology, a plant, specific calculation was performed. .The calculation assumed that only 10,000 gallons of water was'available through the Auxiliary.

Feedwater system. Ten thousand (10,000) gallons is the Technical Specification minimum amount of CST. inventory per operating unit ,

allowed. The plant specific calculation shows that'the minimum  !

CST inventory along with the initial steam generator liquid-inventory is adequate to maintain the decay heat removal.

capability of the steam'ger.ocators for at least one hour of station blackout.

Even though 10,000 gallons has' bean determined to be adequate, (

Wisconsin Electric agrees that additional inventory in.the-condensate storage tanks would provide more time to. shift'the suction of the Auxiliary Feedwater: pumps to the backup source.-

Therefore, based on.the judgement'that the additional time would i i make SBO recovery easier, we will implement the recommended  ;

Technical Specification change. This change will'be submitted for NRC approval by May 1991.

Class 1E Battery. Capacity NRC Recommendation: The licensee should complete the battery.

capacity calculations in conformance: with RG 1.155,E Section 3.2, and include the calculations and results in the documentation:

package supp ting the SBO analyses. The licensee should' develop '

and implema, any modifications that are required to assure 2

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adequate battery capacity to power the needed equipment for an fBO event.

FEPCO ResDonse: Battery capacity calculations are complete for all 4 statio' batteries. The documentation. supporting the SBO analyses has been updated to include the most current calculations. Plant modifications are not required as a result of these calculations.

The Effects of the Loss of Ventilation NRC Recommendation: 1) The licensee should document additional-information to demonstrate the acceptability of the methodology, assumptions, adjacent room effect, and initial conditions used in the heat-up; calculations. 2) The licensee also should confirm that the assumed initial room temperatures for the control and-computer rooms are maximum allowable values and not'just typical values, and if necessary, the room heat-up calculations for these two rooms should be reanalyzed based on the. higher initial temperature. 3) The licensee should document additional justification as to why it is'not necessary to open cabinet doors is the er outer room, t.nd the basis used for determining the number ot and location of ceiling tiles that were removed in the control and computer rooms. 4) The licensee should describe the controls that are to ba used to assure-that the' ceiling tiles are not replaced or reconfigured in the future. The licensee should maintain the additional information.and any analyses performed as a result of these recommendations in the documentation. supporting _

the SBO submictal.

WEPCO Response: These recommendations _for-verifying the loss of ventilation analyses will be implemented by May.1991. If additional analys-3 exe required, they will be complete by November 1991.

Procedures and Training NRC Recommendation: The EOPs should be reviewed and modified accordingly if necessary to account for any changes made to the EDG/GTG configuration or the associated 13.8 kV system, and appropriate training should be implemented to ensure an effective.

response to the SBO.

WEPCO Resoonse: Modifications to Point' Beach are controlled by the use of Nuclear Power Department procedures. These-procedures require the appropriate procedure reviews and updates and-appropriate operator training as part of the modification

-process.

Troposed Modification NRC Recommendation: Installation of additional EDG capacity.

The SBO coping duration and evaluation vould have to bs re-evaluated- subsequent to the licensee pr oviding information on. the installation. >

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WEPCO Resoonse: The SBO coping evaluations and analyses will be amended for these changes in plant configuration at Point Beach.  ;

1 Quality Assurance NRC SER Statement on Ouality Assurangg: The licensee has i committed to incorporate equipment used to cope with an SBO and I not covered by current QA programs into'a QA program that meets the guidance of RG 1.155, Appendix A.

WEPCO Resoonse: QA requirements for'SBO equipment will be I implemented by November 1991. j EDG Reliability Irogran ,

NRC SER Statement on EDG Reliability P:foarsm: The' licensee's submittal on SBO did not specifically address the commitment 1to implement an EDG reliability program to conform to the guidance of RG 1.155, Position 1.2. However, during the site audit review, the licensee stated that their reliability program would  ;

meet these guidelines. The staff finds this to be an acceptable y~

commitment toward meeting-the requirements of the SBO rule.

WEPCO Resoonsg: An EDG reliability program that conforms to the -;

guidance of RG 1.155, Position 1.2, will be established for Point Beach by November 1991.

SER and TER Clarifications j NRC SER Pago 5 First paragraph:- " . . . water to the section of the auxiliary feedwater pumps,..." should state "... water to the suction of the auxiliary feedwater pumps,..."

Page 5 Section 2.3.4: " ... smallest vital switchgear rooms."

should state "... smallest' instrument bus = inverter rooms." i, SAIC TER .

l. i Page 21 Section 5. First paragraph: Valve 755B should be.754B.,

j Page 22 First paragraph: " . . . consideration in accordance.with

[ RG 1.1.55,.Section..." should: state "... consideration ,

in accordance with RG 1.155,' Section...."-

Page 22 Last paragraph: The maximum allowable RCS leakage is 3 l 10'gpm not 25 gpm. Reference TS 15.3.1.D.2. 'i Page 24 The table of equipment: P-195.shouldibe P-105.

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