ML17306A376

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Application for Amends to Licenses NPF-41,NPF-51 & NPF-74, Revising TS Section 3.6.1.7 Action Statements Re Containment Purge Supply & Exhaust Valves for Consistency W/Other Containment Sys Action Requirements
ML17306A376
Person / Time
Site: Palo Verde  Arizona Public Service icon.png
Issue date: 12/30/1991
From: Conway W
ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML17306A377 List:
References
161-04549-WFC-J, 161-4549-WFC-J, NUDOCS 9201070163
Download: ML17306A376 (14)
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Text

ACCELERATED DISTRIBUTION DEMONS'TION SYSTEM j

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9201070163 DOC.DATE: 91/12/30 NOTARIZED: YES DOCKET FACIL:STN-50-528 Palo Verde Nuclear Station, Unit 1, Arizona Publi 05000528 STN-50-529 Palo Verde Nuclear Station, Unit 2, Arizona Publi 05000529 STN-50-530 Palo Verde Nuclear Station, Unit 3, Arizona Publi 05000530 AUTH. NAME AUTHOR AFFILIATION CONWAY,W.F. Arizona Public Service Co. (formerly Arizona Nuclear Power R RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Application for amends to Licenses NPF-41,NPF-51 6 NPF-74, revising TS Section 3.6.1.7 action statements re containment purge supply 6 exhaust valves for consistency w/other containment sys action requirements.

DISTRIBUTION CODE: A001D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: OR Submittal: General Distribution NOTES:STANDARDIZED PLANT 05000528 Standardized plant. 05000529 Standardized plant. 05000530 D

RECIPIENT RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 TRAMMELL,C 2 2 THOMPSON,M 2 2 INTERNAL: ACRS 6 6 NRR/DET/ECMB 7D 1 1 NRR/DET/ESGB 1 1 NRR/DOEA/OTSB1 1 1 1 NOTES'OPIES NRR/DST NRR/DST/SICB8H7 NUDOCS-ABSTRACT 8E2 1 1

1 1

1 1

NRR/DST/SELB 7E NRR/DST/SRXB 8E OC/LFMB 1

1 1

1 1

0 OGC/HDS1 1 0 .E 1 1 RES/DSIR/EIB 1 1 glv EXTERNAL: NRC PDR 1 1 NSIC R D

D D

NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOiVI P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 27 ENCL 25

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Arizona Public Service Company P.O. BOX 53999 ~ PHOENIX, ARIZONA850724999 WILLIAMF. CONWAY 161-04549-WFC/JCO EXECUTIVEVICEPRESIDENT NUCLEAR Docket Nos. STN 50-528/529/530 December 30, 1991 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Station Pl-37 Washington, D. C. 20555

Dear Sirs:

Subj ect: Palo Verde Nuclear Generating Station (PVNGS)

Units 1, 2, and 3 Proposed Technical Specification Amendment to Section 3.6.1.7 File: 91-005-419.05; 91-056-026 Arizona Public Service Company (APS) is requesting an amendment to the ACTION statements of Section 3.6.1.7 for PVNGS Units 1, 2, and 3. This request changes the containment purge supply and exhaust valve ACTION statements to be consistent with other containment system action requirements. Specifically, the proposed ACTION statements will require PVNGS to be in HOT STANDBY, as the first stage of plant shutdown, in lieu of the exi.sting requirement to be in HOT SHUTDOWN in six hours.

Provided in the attachment to this letter, for the proposed Technical Specification amendment, are the following:

A. Description of the Proposed Amendment Request B. Purpose of the Technical Specification C. Need for the Technical Specification Amendment D. Safety Analysis of the Proposed Technical Specification Amendment E. No Significant Hazards Consideration Determination F. Environmental Impact Consideration Determination G. Marked Up Technical Specification Change Pages Pursuant to 10 CFR 50.91(b)(1), a copy of this request is being forwarded to the Arizona Radiation Regulatory Agency.

If you should have any questions, please contact Michael E. Powell of my staff at (602) 340-4981.

Sincerely, WFC/JCO/jco Attachment cc: J. B. Martin D. H. Coe A. C. Gehr A. H. Gutterman

~nc II'.920i070163 Tedford 5'11230 PDR ADOCK 05000528 P PDR

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161-04549-WFC/JCO December 30, 1991 ATTACHMENT A. Descri tion of the Pro osed Amendment Re uest Technical Specification 3.6.1.7 ACTION Statements a., b., and c. will be changed to require the first stage of plant shutdown to be HOT STANDBY, in lieu of the existing HOT SHUTDOWN.

This change makes the Specification 3.6.1.7 ACTION Statements consistent with the ACTION requirements of the other Containment Systems described in Technical Specification, Section 3.6 and the generic Limiting Condition for Operation (LCO) 3.0.3. This change also makes Technical Specification 3.6.1.7 ACTION statements consistent with the wording contained in LCO 3.6.1.8 of NUREG 0212, Draft Revision 3, the basis for the Palo Verde Nuclear Generating Station (PVNGS)

Technical Specifications.

B. Pur ose of the Technical S ecification Technical Specification 3.6.1.7 ensures that: (1) each 42-inch containment purge supply and exhaust isolation valve is OPERABLE and sealed closed during Plant Operating MODES 1, 2, 3, and 4, and (2) the 8-inch containment purge supply and exhaust isolation valves are operable and sealed closed "to the maximum extent practicable but may be open for purge system operation for pressure control, for ALARA and respirable air quality considerations for personnel entry and for surveillance tests" during MODES 1 through 4.

The BASES for Specification 3.6.1.7 indicates that the 42-inch containment purge supply and exhaust isolation valves are required to be closed during plant operation because these valves have not been demonstrated capable of closing during a Loss of Coolant Accident (LOCA) or steam line break accident.

The BASES for the 8-inch valves indicates that unlike the 42-inch valves, the 8-inch purge supply and exhaust valves will close during a LOCA or steam line break accident.

The purpose of the Technical Specification, therefore, ensures that the site boundary guidelines of 10 CFR 100 will not be exceeded in the event of an accident during purging operations as described in UFSAR 'Sections 15.1.5 (steam line break) and 15.6 ' (LOCA). See also UFSAR 6.2.4, 7.3 and 9.4 for Purge Valve Isolation description.

C. Need for the Technical S ecification Amendment ACTION statement a. for the 42-inch containment purge supply and exhaust isolation valve(s) requires that for one valve open or not sealed closed, the valve be closed or sealed closed; or isolate the penetration within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />; or be in at least HOT SHUTDOWN within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. Should two valves become inoperable or not sealed closed, Specification 3.0.3 would apply. Specification 3.0.3 requires action to be taken within one hour to place the plant in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

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4 1' t 161-04549-WFC/JCO December 30, 1991 The current ACTION requirement for one valve in non-compliance is more restrictive than two valves in non'-compliance. One valve in non-compliance requires that the valve be closed within four hours or the plant be placed in HOT SHUTDOWN (K,z< <0.99; 0% Rated Thermal Power (RTP); Tzz between 350' and within the next six hours.

210')

LCO 3.0.3 applies for two valves in non-compliance. LCO 3.0.3 requires that the valves be closed within one hour, otherwise the plant must be placed in HOT STANDBY (k,zz <0.99; 0% RTP; T~q >350')

within six hours. Therefore, one valve in non-compliance results in a greater plant cooldown than two valves in non-compliance. This is inconsistent with the graded nature of ACTION requirements and is overly restrictive for one valve being inoperable.

Recognizing that the ACTION statements for each of the Containment Systems consistently specify the first stage of plant shutdown as HOT STANDBY and not HOT SHUTDOWN (3.6.1.1, 3.6.1.3, 3.6.1.4, 3.6.1.5, 3.6.1.6, 3.6.2.1, 3.6.2.2, 3.6.3, 3.6.4.1, 3.6.4.2 and 3.6 '.3) and that Specification 3.0.3 specifies HOT STANDBY, the existing Technical Specification 3.6.1.7 ACTION statement requirement to go to HOT SHUTDOWN is overly restrictive.

The source of the existing inconsistent ACTION requirements is the apparent inadvertent substitution of the Boiling Water Reactor (BWR) (Shoreham) ACTION requirements during the resolution of the containment purge issue during PVNGS licensing. The NRC staff, during the licensing of Unit 1, used the Shoreham Technical Specifications as an example of acceptable wording for LCO 3.6.1.7.

The operations mode of HOT SHUTDOWN for a BWR is similar to the PVNGS (CE-PWR) operating mode of HOT STANDBY, for purposes of this ACTION statement, and not HOT SHUTDOWN as currently specified in the 3.6.1.7 ACTION statements. This change is consistent with the wording contained in LCO 3.6.1.8 of NUREG 0212, Draft Revision 3, the basis for the PVNGS Technical Specifications.

ACTION Statement b. for one 8-inch containment purge supply and/or exhaust isolation valve(s) open, for reasons other than those given in the LCO, requires the valve(s) must be closed or the penetration isolated within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, otherwise the plant must be in HOT SHUTDOWN within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. As for the 42-inch valves, this ACTION statement needs to be changed to achieve consistency within the Technical Specifications and eliminate unwarranted plant cooldowns.

ACTION Statement c. for containment purge supply and exhaust isolation valve leakage should be changed to require HOT STANDBY as the initial stage for plant shutdown rather than HOT SHUTDOWN for the same reasons provided for ACTION statements a. and b. above.

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D. Safet Anal sis of the Pro osed Technical S ecification Amendment The proposed amendment resolves an inconsistency, in the ACTION requirements for the containment purge exhaust and supply isolation valves. The resolution of this inconsistency will provide an increase in the margin of safety by reducing the potential need for accelerated plant cooldowns to, HOT SHUTDOWN when 'a containment purge supply.'or exhaust isolation valve is inoperable.

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161-04549-CFC/JCO December 30 , 1 9 9 1 The limiting dose consequences for steam 1 ine breaks (UFSAR Section 15 . 1 . 5 . 4 )

results from breaks outside contai nment at full power , for which containment purge isolation does not have a meaningful dose contribution . The limiting dose consequences for LOCA (UFSAR Section 15 . 6 . 5 ) re sul t from a Large Break LOCA from a conservatively assumed 102% power . The durati.on of plant operation at either HOT STANDBY or HOT SHUTDOWN in the event of a 42 - inch or 8 - inch purge isolation valve being inoperable is no t a meaningful contributor to dose since the analysis assumes 102 power as the initial condition for the Large Break LOCA which would result in higher doses than a Large Break LOCA from either HOT STANDBY or HOT SHUTDOWN . Therefore , the limiting UFSAR analyses are unaffected by the proposed Technical Specification amendment .

E. No S i ni ficant Hazards Cons iderati on De terming tion The Commission has provided standards for de termining whether a significant hazards consideration exists as stated in 10 CFR 50 . 9 2 . A proposed amendment to an operating license for a facility involves no s ignificant hazards cons ideration if operation of the facility in accordance with a proposed amendment would no t:

( 1 ) involve a significant increas e in the probability or consequences of an accident previously evaluated; or ( 2 ) create the possibility of a new or different kind of accident from any accident previously evaluated; or ( 3 ) involve a s ignificant reduction in a margin of safety .

A discussion of these standards as they relate to the amendment reques t follows :

I Standard 1: Involve a significant increase in the probability or consequences of an accident previously evaluated.'-

The proposed amendment does not affect the probability or consequences of an acci.'dent previously evaluated because the plant being in either HOT SHUTDOWN or HOT STANDBY, as the first stage of plant shutdown, has no impact on the assumptions made in the limiting accident analyses, Steam Line Break (15.1.5) and

, Large Break LOCA (15.6.5). The plant being't 0% power (HOT STANDBY) would result in no increase in the probability of occurrence of the events.

Standard 2: Create the possibility of a new or different kind of accident from any accident previously evaluated.

The first stage of plant shutdown to comply with a LCO has no effect on the type of accident to which the plant could be exposed. Both HOT SHUTDOWN and HOT STANDBY are plant modes for which the facility has been analyzed; therefore, no new or different kind of accident from any previously evaluated will be created.

Standard 3: Involve a significant reduction in a margin of safety.

The proposed change from HOT SHUTDOWN to HOT STANDBY as the first stage of plant shutdown for the ACTION statements for Specification 3.6.1.7 will increase the margin of safety by reducing the potential for accelerated plant cooldowns to HOT SHUTDOWN, consistent with the other PVNGS Containment System Action statements.

Therefore, the proposed change will not reduce the margin of safety.

t 161-04549-WFC/JCO December 30, 1991 F. 'nvi'ronmental Im act Consideration Determination The proposed amendment changes the ACTION statement requirements for either one 42" 'containment purge or one 8" containment purge valve in non-compliance with the Technical Specification.

Arizona Public Service Company has determined that the proposed amendments involve no change in the amount or type of any effluent that may be released offsite, and there is no increase in individual or cumulative occupational radiation exposure. As such, operation of PVNGS Units 1, 2, and 3 in accordance with the proposed amendment does not involve an environmental impact.

G., Marked-U Technical S ecification Chan e Pa es PVNGS Unit 1 PVNGS Unit 2 PVNGS Unit 3 3/4 6-14 3/4 6-14 3/4 6-14

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161-04549-t9FC/JCO December 30, 1991 STATE OF ARIZONA )

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COUNTY OF MARICOPA )

I, W. F. Conway, represent that I am Executive Vice President Nuclear, that the foregoing document has been signed by me on behalf of Arizona Public Service Company with full authority to do so, that I have read such document and know its contents, and that to the best of my knowledge and belief, the statements made therein are true and correct.

W. F. Conway Sworn To Before Me This N0 Day Of 1991.

Notary 'Public My Commission Expires

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