ML20151V786

Application for Amend to License NPF-68,clarifying That RHR Cold Leg Injection Valves HV-8809A & HV-8809B May Be Temporarily Closed in Mode 3 During Leakage Testing of RCS Pressure Isolation Check Valves.Fee Paid

ML20151V786
Person / Time
Site:	Vogtle
Issue date:	08/12/1988
From:	Hairston W GEORGIA POWER CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
Shared Package
ML20151V789	List: ML20151V786 ML20151V790
References
NUDOCS 8808230005
Download: ML20151V786 (8)

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', Gptgia Power Company

. 333 Piedmont Avenue

• At!anta, Georgia 30308 g TeMphone 404 526 65?6 i Mailing Address:

' Post Off ce 3ox 4545 ,,

Atlanta. Georg4a 30302 j GeorgiaPower Nuclear operations Department f'e sa #N" ** 17C 5 ksh"n viA6 0970m X7GJ17-V600  !

August 12, 1983 ,

i U. S. Nuclear Regulatory Commission ATTN: Document Control Desk 1 Washington, D.C. 20555 l PLANT V0GTLF - UNIT 1 i NRC DOCKET 50-424 )

OPERATING LICENSE NPF-68 REQUEST TO RcVISE TECHNICAL SPECIFICATION 4.5.2 l

Gentlemen

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In accordance with 10 CFR 50.90 as required by 10 CFR 50.59(c)(1),

Georgia Power Company (GPC) hereby propose", to amend the Vogtle Electric j Generating Plant Unit 1 Technical Specifications, Appendix A to Operating '

License NPF-68.

The proposed amendment clarifies that Residual Heat Removal Cold Leg Injection Yalves HV-8809A and B may be temporarily closed in Mode 3 during leakage testing of reactor coolant system pressure isolation check 4 valves. l Enclosure 1 provides a detailed description of the proposer. change and the basis for the cha' ige request.

Enclosure 2 details the basis for our determination that the proposed change does not involve significant hazards considerations.

Enclosure 3 provides page change instructions for incorporating the i proposed change. The proposed revised Technical Specification pages follow Enclosure 3.

In accordance with 10 CFR 1/0.12, a check for t150.00 is enclosed in pcyment of the required application fee.

A copy of this letter and all applicable enclosures will be sent to ,

the designated state official in accordance with 10 CFR 50.91. '

The Yogtle Plant Review Board and the GPC Safety Review Board have reviewed and concur with this proposed amendment.

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l U. S. Nuclear Regulatory Commission August 12, 1988 Page Two Mr. W. G. Hairston, III states that he is a Senior Vice President of Georgia Power Company and is authorized to execute this oath on behalf of Georgia Power Company, and that to the best of his knowledge and belief, the facts set forth in this letter and enclosures are true.

GEORGIA POWER COMPANY By: b .

M W. G. Hairston, III Sworn to and subscribed before me this 12th day of August 1988.

E .

~se Difeeg Notary Public JH/1m

Enclosures:

1. Bar.is for Proposed Change l

2. 10 CFR 50.92 Evaluation  !

3. Instructions for Incorporation l

4. Check for Application Fee j c: Georgia Power Company 1 Mr. P. D. Rice Mr. G. Bockhold, Jr. i GO-NORMS U. S. Nuclear Regulatory Commission Dr. J. N. Grace, Regional Administrator Mr. J. B. Hopkins, Licensing Project Manager, NRR (2 copies)

Mr. J. F. Rogge, Senior Resident Inspector-Operations, Vogtle St&te of Georgia Mr. J. L. Ledbetter, Commissioner - Department of Natural Resources 0970m 77,

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ENCLOSURE 1 PLANT V0GTLE - UNIT 1 NRC DOCKET 50-424 OPERATING LICENSE NPF-68 REQUEST TO REVISE TECHNICAL SPECIFICATION 4.5.2 BASIS FOR PROPOSED CHANGE PROPOSED CHANGE Specification 4.5.2.a. applicable in Modes 1, 2, and 3, currently requires that Residual Heat Removal (RHR) Pump Cold Leg Injection Valves HV-8809A and B be verified to be open with their power lockout switches in the lockout position at least once per twelve hours. The proposed amendment adds a footnote for valves HV-8809A and B which would read as follcws:

• Either valve may be realigned in Mode 3 for testing pursuant to Specification 4.4.6.2.2.

In addition, add the following to the Bases of Specification 3/4.5.2:

"The Surveillance Requi rements for leakage testing of ECCS check valves ensures tha. a failure of one valve will not cause an intersystem LOCA. In Mode 3, with either HV-8809A or B closed for ECCS check valve leak testing, adequate ECCS flow for core cooling in the event of a LOCA is assured."

BASIS The proposed change specifies that valves HV-8809A and B may be temporarily closed in Mode 3 daring leak testing of Reactor Coolant System (RCS) pressure isolation check valves. Leak testing of : these check valves is required by Specification 4.4.6.2.2 following each refueling outage, following valt a realignment or maintenance, and prior to entering Mode 2 following a cold shutdown of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or more (if not tested in t previous 9 months). The optimum plant condition for leak testing of the pressure isolation check valves is Mode 3 at full RCS pressure, just prior to entering Mode 2. At this point, valve disturbances are complete and better seating of the check valves will produce more meaningful test results. This testing procedure was described to the NRC in GPC letter SL-3505 dated October 27, 1987 and has received NRC concurrence. NRC approval was documented in a November 5, 1987 NRC letter and Section 5.4.7 of Supplement 7 to NUREG-1137, the Vogtle Safety Evaluation Report (SER).

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ENCLOSURE 2 PLANT V0GTLE - UNIT 1 NRC DOCKET 50-424 OPERATING LICENSE NPF-68 REQUEST TO REVISE TECHNICAL SPECIFICATICN 4.5.2 10 CFR-50.92 EVALUATION In accordance with 10 CFR 50.92, Georgia Power Company has evaluated the attached proposed amendment to the Technical Specifications and has determined that operation of the facility in accordance with the proposed amendment would not involve significant hazards considerations. The basis for this detennination is as follows:

PROPOSED CHANGE Specification 4.5.2.a, applicable in Modes 1, 2, and 3, currently requires that RHR Pump Cold Leg Injection Valves HV-8809A and B be verified to be open with their power lockout switches in the lockout position at least once per twelve hours. The proposed amendment adds a footnote for valves HV-8809A and B which would read as follows:

• Either valve may be realigned in Mode 3 for testing pursuant to Specification 4.4.6.2.2.

In addition, add the following to the Bases of Specification 3/4.5.2:

"The Surveillance Requirements for leakage testi ng of ECCS check '

valves ensures that a failure of one valve will not cause an intersystem LOCA. In Mode 3, with either HV-8809A or B closed for I ECCS check valve leak testing, adequate ECCS flow for core cooling in the event of a LOCA is assured."

BACKGROUND FSAR Section 6.3.4.2 discusses leak rate testing of the check valves in the discharge lines from the Safety Injection (SI) and RHR pumps to the RCS cold and hot legs. The NRC's position on testing these valves is provided in NUREG-0677, "The Probability of Intersystem LOCA: Impact Due I to Leak Testing and Operational Changes", May 1980. Additional discussion of the NRC's position is provided in Vogtle FSAR Question 210.48. Specifically, "Leak testing sho t. '. d be performed after all i disturbances to the valves are complete, prior to reaching power operation following a refueling outage, maintenance, etc." This forms  :'

the basis for Technical Specification 4.4.6.2.2.

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' Georgia Power d ENCLOSURE 2 (Continued)

REQUEST TO REVISE. TECHNICAL SPECIFICATION 4.5.2 10-CFR 50.92-EVALUATION ,

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Leak testing these valves requires -temporary isolation of portions of. i the ECCS. During performance of leak testing, the RHR Cold Leg Injection Valvos HV-8809A and B are temporarily closed, thereby' precluding RHR pump ,

flow into the two affected discharge lines into the RCS cold legs.

Automatic SI actuation is available, as well as accumulator injection, and intemediate and high head SI pumps.

Other ECCS configurations also exist during shutdown modes. During Mode 3 as RCS pressure is reduced, the operator is required to manually block the' automatic SI actuation on pressurizer low pressure at i approximately 1900 psig. At 1000 psig, the operator closes and locks out the accumulator discharge valves. These actions prevent inadvertent SI )

actuation and accumulater delivery during shutdown. In Mode 4 (RCS )

temperature below 350 degrees Fahrenheit), both SI pumps are rendered 1 inoperable to preclude an RCS overpressurization event.

The impact on the LOCA analyses has been analyzed for shutdown Modes 3 and 4 where portions of the ECCS are temporarily disabled. These analyses were conducted in conjunction with Vogtle Safety Evaluation Report (SER) Confirmatory Item 22 and are described in GPC letters to the NRC dated December 9,1985 and June 13, 1986. The analyses show that the oesign basis performance of the ECCS is adequate to meet the requirements for core cooling following a large break LOCA with minimum ECCS equipment available and without immediate operator action.

The analyses described are conservative with respect to the plant conditions during conduct of the check valve leak rate testing. The analyses utilized core decay heat at two and one-half hours following shutdown as compared to the significantly reduced decay heat that would be present following several days of shutdown. Further, the analyses assumed that automatic SI actuation on low pressurizer pressure was blocked; thus, only automatic SI actuation on containment high pressure I

was available. The analyses also considered ECCS configurations which are more restrictive than those established during check valve testing, i.e., flow from only one RHR pump, one intemediate head SI pump, and one high head charging pump. Check valve testing at Plant Vogtle is conducted just prior to plant startup, in Mode 3 at full RCS pressure.

Automatic SI actuation is available at the higher RCS pressure.

Additionally, all ECCS pumps, as well as the accumulators, are available. Under these conditions, the available ECCS flow is more than I adequate to meet the requirements for core cooling following a large break LOCA.

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'GeorgiaPoker A ENCLOSURE 2 (Continued) 4 REQUEST TO REVISE TECHNICAL SPECIFICATION 4.5.2 10 CFR 50.92 EVALUATION Probabilistic analyses were also conducted to detemine the impact on s1 '

RHR or low head SI unavailabilities due to closure of valves 1HV-8809A or B to conduct check valve leak rate testing. The results show that closure of the discharge valves 'does not adversely impact the safety of the plant if the duration and frequency are less than two hours every nine months. Although closure 4 of valves 'HV-8809A and B results in a degraded configuration, the time period for this configuration is short and because of this, the impact on RHR system availability is not significant.  ;

On the basis of this review, GPC believes that leak rate testing of  ;

the RCS pressure isolation valves in Mode 3 is appropriate. l Consideration has been given to testing the valves at low RCS pressure ]

(approximately 1000 psig) and at full RCS pressure (approximately 2235 l psig). Testing at the higher pressure provides more meaningful test I results due to better seating of the check valves. Additionally, at the j higher pressure automatic SI actuation is available.

ANALYSIS GPC has reviewed the proposed change with respect to the requirements of 10 CFR 50.92 and has detemined that the change does not involve significant hazards considerations. In support of this conclusion, the j following analysis is previded:

1. The proposed change will not significantly increase the probability or consequences of an accident previously evaluated. Closure of valves HV-8809A and B to allow RCS pr-essure isolation check valve testing in Mode 3 has no impact on any mechanism that could potentially cause a LOCA. The probability of a LOCA is therefore not  !

increased. The consequences of a LOCA occurring with either HV-8809A or B closed are bounded by previous analyses of a LOCA in Mode 3 with portions of the ECCS disabled. Those previous analyses were l performed assuming flow was available from one RHR pump, one i intennediate head SI pump, and one high head charging pump. Further, the analyses assumed that automatic SI actuation on low pressurizer pressure was blocked; thus, only automatic SI actuation on containment high pressure was available. In actuality, during leak testing of the pressure isolation check valves, all ECCS pumps and accumulators (above 1000 psig) are available. In addition, automatic 0970m E2-3 08/12/88 VL-36 i

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+ . ENCLOSURE 2 iContinued)'

s REQUEST TO REVISE TECHNICAi.LSPECIFICATION 4.5.2 10'CFR'50.92 EVALUATION SI actuation on low pressurizer - pressure is available above approximately 1900 psig when the operator unblocks this signal. The ~

analyses;showed that adequate ECCS flow- was available to meet core cooling requirements and that _ the ECCS design - and licensing- bases were satisfied. The consequences of a LOCA are therefore not increased; '

2. R proposed change does not' create the possibility of a new or - ,

different kind of accident than any accident previously evaluated..

The change does not introduce any new equipment into the plant or require any existing equipment to operate in a different manner from l

which it .was designed to operate. The change, therefore, does not .

create a new failure mode and a new or different kind of accident i could not result. i

3. The proposed change does not significantly reduce a margin c' safety. The change has no effect on safety limits or limiting safety >

system settings. Probabilistic analyses have shown that RHR or low head SI unavailabilities are not significantly increased by periodic, temporary closures of valves _ HV-8809A and B for pressure isolation check valve leak testing. Margins of safety are therefore not.  ;

significantly reduced.

CONCLUSION Based on the preceding analysis, GPC has detennined.that the proposed change to the Technical Specifications will not significantly increase the probability or consequences of an accident previously evaluated, create the possibility of a new or different kind of accident from any

, accident previously evaluated, or involve a significant reduction in a 4

margin of safety. GPC therefore concludes that. the proposed change meets the requirements of 10 CFR 5').92(c) and does not involve significant hazards considerations.

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- ENCLOSURE 3 PLANT V0GTLE - UNIT 1 -

NRC DOCKET 50-424 CPERATING LICENSE NPF-68 REQUEST TO REVISE TECHNICAL SPECIFICATION 4.5.2 INSTRUCTIONS FOR INCORPORATION The proposed amendment to the Technical Specifications (Appendix A to Operating License NPF-68) would be incorporated as follows:

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