ML20073D515

Suppl 1 to Amend Application 114 to License NPF-15, Consisting of Proposed TS Change 329,revising TS 3/4.7.1, Turbine Cycle to Increase as-found Setpoint Tolerance for MSSVs

ML20073D515
Person / Time
Site:	San Onofre
Issue date:	09/22/1994
From:	Rosenblum R SOUTHERN CALIFORNIA EDISON CO.
To:
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ML20073D497	List: ML20073D492 ML20073D502 ML20073D515 ML20073D529
References
NUDOCS 9409270258
Download: ML20073D515 (11)

Text

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UNITED STATES OF AMERICA l

NUCLEAR REGULATORY COMMISSION l

Application of SOUTHERN CALIFORNIA

)

. Docket No. 50-362 l

EDIS0N COMPANY, ET AL. for a class 103

)

License to Acquire, Possess, and Use a Utilization Facility as Part of Amendment Application Unit 3 of the San Onofre Nuclear

)

No. 114 Generating Station

)

SOUTHERN CALIFORNIA EDISON COMPANY, ET AL. pursuant to 10 CFR 50.90, hereby submit Amendment Application No. 114.

This amendment application consists of proposed Technical Specification Change No. NPF-15-329 to Facility Operating License No. NPF-15.

Proposed Technical Specification Change NPF-15-329 will revise Technical Specification 3/4.7.1.1, " Turbine Cycle." This proposed change will increase the as-found setpoint tolerance for the Main Steam Safety Valves (MSSVs) from +/-1% to

+2%/-3%. The existing ACTION statement will be revised to require HOT STANDBY SHgTDOWNinsteadofHOTCp[DSHUTDOWN. Tcble 3.7 2 will be revi:cd to require c

$ag.1 reduction in stecdy :t tc Oper ting-pcwcr with MSSV; INOPERABLE. Also included in this proposed change are several editorial, format, and Bases changes which clarify the intent of this TS.

9409270258 940922 PDR ADOCK 05000361 P

PDR

Subscribed on this 22nd day of dE/TEmotR 1994.

Respectfully submitted, SOUTHERN CALIFORNIA EDISON COMPANY I

By:

n A

Rich'ar'd. M. Rosenblum Vice President State of California of Orange y gg4y 'Pu o L / C >

County /.2 2/9Q before me, M d M A A M d ersonally On 7 appeared 8sc'uArm Af. )?ciruRuin personally known to me to be the person whose name is subscribed to the within instrument and acknowledged to me that he executed the same in his authorized capacity, and that by his signature on the instrument the person, or the entity upon behalf of which the person acted, executed the instrument.

WITNESS my hand and official seal.

v ___

9 BARBARA OFRCML SEAL h

d-ORANGE Signature w w w.,

Much 81,1995 p

l l

1 l

DESCRIPTION AND SAFETY ANALYSIS OF PROPOSED CHANGE NPF 10/15-329,iSupplementf1 ligt.1 This is a request to revise Technical Specification (TS) 3/4.7.1, " Turbine Cycle." This change will increase the as-found setpoint tolerance of the Main Steam Safety Valves (MSSVs). The existing ACTION statement will be revised to require HOT STANDM SHUTDOWN instead of HOT COLD SHUTDOWN.

able 3.7 2..ill be revised to req dre ;^reduetk n in steady statc~ operating power '..ith MSSW g,R,1 M GPERABLEr Also included in this change are several format changes which clarify the intent of the TS.

Existing Specifications Unit 2: Attachment "A" Unit 3: Attachment "B" Proposed Specifications Unit 2: Attachment "C" Unit 3: Attachment "D" Description The following changes are requested as part of this TS change:

1)

Revise Table 3.7-1 to increase the as-found setpoint tolerance of the MSSVs from +/-1% to +2%/-3%. Add a footnote to Table 3.7-1 to indicate that the setpoint tolerance for the lowest set pair of MSSVs will be +1%/-3%.

2)

Add a footnote to TS 3.7.1.1 and revise footnote 1 of Table 3.7-1 to clarify that the MSSVs will be left at the lift setting according to Table 3.7-1 within a +/-1% tolerance following inservice testing.

3)

Add the following ACTION statement for the case of less than 5 MSSVs OPERABLE per OPERABLE Steam Generator (SG):

"With one or more Steam Generators having less than five main steam safety valves OPERABLE, be 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 in HOT SHU1DOWN within the following 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />."

4)

Revise the existing ACTION statement to require "H0T SHUTDOWN within the following 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />" instead of " 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 />."

5)

Revise the format of column 1 and the title of Table 3.7-2 to 1

require aniexact m4Maum number ~ of'0PERABLE MSSVs instead of a maximum number'of INOPERABLE MSSVs.

6)

Pcvice the title and column 2 cf t-air +c 3.7 2 to require " Maximum M4ewalde Steady State Power" instead of "Madmum f.llowable Value t-inear Pcwcr Level High Trip" and reduce the allowable steady state g

1 power values to provide mart +,-fer power indication error.

T i

A)6)

Delete the ORIFICE SIZE column of Table 3.7-1r-end.

i l

. &}7)

Revise the Bases to reflect these changes.

8);

_ Revise page'XIX of the Index to1 reflect;the1 change to^theiTitle of 591 Table.3.7-2.

These changes are requested to provide flexibility in testing and resetting the MSSVs, and provide clearcr and more appropriate actions when MSSVs are determined to be IN0PLRABLE.

These changes are acceptable because they maintain the intent of the TS, which is to ensure sufficient overpressure relief and heat removal capacity through the MSSVs for any postulated accident.

Discussion The proposed changes and their justification are described below:

1)

Increase the setpoint tolerance of the MSSVs from +/-1% to +2%/-3%.

L The heading of Column 3 of Table 3.7-1 will be revised to read " Lift Setting."

Footnote 1 of Table 3.7-1 will be revised to require an as-found setpoint tolerance of +2%/-3% and an as-left tolerance of +/-1%.

By incorporating the as-found tolerance requirement of +2%/-3%, readjustment of the MSSVs to within the as-left +/-1% tolerance requirement may be accomplished without the time constraints of entering the 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> ACTION statement of TS 3.7.1.1.

This change is requested to increase the allowable lift setting tolerance for normal MSSV setpoint drift. This change is acceptable because the MSSVs are still capable of performing their design functions when set within +2%/-3% of their setpoint as discussed below.

The specific considerations are overpressurization, small break Loss of Coolant Accident (LOCA), and Steam Generator Tube Rupture (SGTR).

Overpressurization The upper limit for lift pressures of 2% above existing TS setpoints is an increase from the +1% tolerance in the existing TS.

This results in an increase in the maximum lift pressure of the valves.

MSSVs are designed to prevent overpressurization of the SGs and associated equipment and to provide a passive heat sink.

These design functions can be met provided actual lift setpoints are less than or equal to the limiting lift setpoint assumed in the overpressurization analyses.

The limiting overpressurization events are the Loss of Condenser Vacuum (LOCV) and the feedwater Line Break (FWLB).

The LOCV and FWLB events were reanalyzed assuming lift setpoints 2% above existing TS setpoints.

For the LOCV the peak primary and secondary pressures must remain less than 2750 psia and 1210 psia, respectively. The peak primary pressure increases from 2732 psia to 2734 psia.

The peak secondary pressure increases from 1186 psia to 1195 psia. The FWLB peak primary and secondary pressures must remain less than 3000 psia and 1210 psia, respectively.

Peak primary pressure does not increase f rom the current value of 2911 psia.

Peak secondary pressure increases from 1150 psia to 1160 psia.

For both of these events peak primary and secondary pressures remain below the maximum allowed.

The lower allowable lift pressure for each MSSV will be lowered by 2% (from -1%

below the setpoint to -3% below the setpoint) as a result of this change.

Reanalyses performed to support the setpoint tolerance expansion demonstrate that the overpressure relief requirements for the bounding events, LOCV and

3-FWLB, are met f f all MSSVs are set as low as 1067 psia.

In accordance with this change, the lowest allowable lift pressure of the lowest set MSSV will be 1067 psia. Therefore, this change does not present an adverse safety consequence.

The proposed as-found setpoints have a marginal effect on transient Departure from Nucleate Boiling Ratio (DNBR).

However, TS 3/4.2.4 reserves adequate DNBR overpower margin to ensure specified acceptable fuel design limits are not exceeded in the event of an Anticipated Operational Occurrence.

The limiting required DNBR overpower margin is not adversely affected by this proposed change to MSSV setpoints.

Small Break LOCA The lift setpoint of the lowest set MSSVs affects secondary pressures and temperatures following a Design Basis Event (DBE) with a loss of normal secondary heat sink. Therefore, raising the upper limit of lift pressures over existing values would affect the initial conditions of the small break LOCA analyses.

This event has not been reanalyzed.

Instead, a footnote to column 3 of Table 3.7-1 will be added as part of this change to require that the lowest set pair of valves will be maintained at 1100 psia +1/-3%.

This results in no change to the highest allowable lift pressure for the lowest set pair of valves.

Therefore, no reanalysis is necessary.

Steam Generator Tube Ruoture This change results in a lowest allowable limit of 1067 psia for the pair of valves set at the lowest relief setting of 1100 psia.

This is a reduction from 1089 psia, which is the current limit of 1% below the existing setpoint.

Operation of this pair of MSSVs at reduced pressure can impact radiological releases and primary-to-secondary leakage following a SGTR. The SGTR analysis was examined, and it was determined that the MSSV model used in the SGTR analysis bounds the characteristics of an MSSV with setpoints as low as 1067 psia. Therefore, the minimum lift pressure of 1067 psia for the pair of MSSVs set at 1100 psia is acceptable.

Operation with Inocerable MSSVs Table' 3.'7f2providesJreducedtripsettings'for4thelline'riPower-High:ltrip:1for a

operation withLinoperable MSSVs. jThe reduced)tripisettingsfensure sufficient relief and. heat'- removal capacity are availableithrough{the) remaining OP.ERABLE MSSVs.

The basis for the currentireducedctriplsettingstassumesfa;maximumLMSSV L.1 setpoints:. tolerance.of +1L 5 However? the existino? Table?3$2rprovides

~

pp appropriate; allowable values:for the: Linear 70weEHigh Trip lwithJinopeHMe MSSVs based on the origina1LCombustion:EngineeringL(CE)? standard TSs4 j fse i

power level values are conservative when compared to:limitingWalues provided;by CE;for.afLoss of1Condenserc_ Vacuum (with 4 Single;Fai_luref(which?istthe Rimiting event)? assuming MSSVsihavela setpoint" toleranceioftupJtoW2L 2)

Add a footnote to Limiting Condition for Operation (LCO) 3.7.1.1 and revise footnote 1 of Table 3.7-1 to clarify that the MSSVs will be left within a +/-l% tolerance following inservice testing.

This proposed footnote is added to clarify the difference between "as-found" and "as-left" conditions of the MSSVs.

If. following inservice testing according to TS 4.0.5, an MSSV is found to be within +2%/-3% of its setpoint, but outside the

4-as-left requirement of +/-1% of the setpoint, it will be considered OPERABLE in accordance with LCO 3.7.1.1.

However, in accordance with this footnote, the MSSV must be returned to within +/-1%.

The purpose of returning to +/-1% is to reduce the potential of the setpoint drifting outside the +2%/-3% tolerance range before the next scheduled inservice testing.

3)

Add ACTION b for the case of less than 5 MSSVs OPERABLE per OPERABLE SG.

l A second ACTION statement will be adden to LC0 3.7.1.1.

This is a clarification l

to reflect that with less than 5 MSSVs OPERABLE the plant must be in HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and HOT SHUTDOWN within an additional 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This precludes j

the need to enter TS 3.0.3 when less than 5 MSSVs are OPERABLE.

4)

Revise ACTION a to require entry into HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> instead of COLD SHUTDOWN in 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

The existing ACTION a for LC0 3.7.1.1 requires entry into COLD SHUTDOWN within 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> if the action specified in Table 3.7-2 is not met. The proposed change requires entry into HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

The LCOs for MSSVs are not applicable in Mode 4 (H0T SHUTDOWN). Therefore, the appropriate action if the LC0 cannot be met is to enter Mode 4.

The completion time is shortened to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> because of the seriousness of the conditions requiring Mode 4 entry. Also included in the change to ACTION a is deletion of the option of restoring the inoperable valves to OPERABLE status.

Restoring INOPERABLE MSSVs to OPERABLE status causes automatic exit from the LCO.

Therefore, it is not necessary to state this in the ACTION statement.

5)

Revise the format of column 1 andithe~ title of Table 3.7-2.

The format of column 1 of Table 3.7-2 is revised to specify the exactek4mm number of OPERABLE MSSVs per OPERABLE SG as opposed to a maximum ~riUmber of INOPERABLE MSSVs per OPERABLE SG. ThettitleiofiTable737742 3s r.efl ecti th_e Tch..angeTtoTc61 umn111 Th i s~ i s ~ an1d i t ori'aIch ahgh. i revi se

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c 6)

P,cvi:0 +he title and column 2 cf Table 3.7 2 to require " Maximum Allcwable Steady State Pcwcr" instead of " Maximum A11:w;bic V 1u: Linear Pcwcr Level High Trip" and reduce the allcwable steady : tate pcwcr value; to provide : rgin.

The ex hting ACTION for LC0 3.7.1.1 require the high linc:r power trip setpcint gd1-tc be reduced in ;cccrdance with T;ble 3.7 2 when MSSV ;r incper bk.

The prcpc:cd ACTION will nc icnger require icwcrkg cf the trip : tpcint, but will require : reductica k the allowable tc;dy state power durhg period: with inoperabic MSSV:. Th h change h requested becau;c 10 cr bg the trip ::tpcint:

h r unnecc : ry ctica whkh cc plicate: completh; the ACTION for LCO 3.7.1.1 within the required i Scurs.

The prepc:cd allow;ble Operating pcwcr: in Table 3.7 2 ;re b :cd en :n:ly c:

dc:cn:t+atbg acceptable overprc urhatten rc ult; for the bcundhg events, FWLB :nd LOCV. The:c prepc cd 110:051 Operating pcwer: Orc : lightly decrc :cd frc: cxhtkg vahc; tc allow for crrcr tolerancc: in th: :tcady state power indicatien.

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Delete the "0RIFICE SIZE" column of Table 3.7-1.

The orifice size of the MSSVs is not variable. This information is therefore not relevant and should be remov e nescriptions of the MSSV relieving capacities are in the Bases for TS 1.7.1.1.

Q7)l Revise the Bases to TS 3/4.7.1 to provide consistency with the above

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changes.

The proposed Bases section reflects the change to an expanded as-found setpoint tolerance and the proposed ACTION statement requiring at least five MSSVs r

OPERABLE in'Mo' des 1 through 3,.

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ItemT4TreMse~sithEtitle?of2 Table 13M ?Jto?" MAXIMUM T ALLOWABLE}VALUE 7 LINEAR 5 POWER (Ip.1 LEVEGHIGH; TRIP;WITH OPERABLESMAIN STEAM SAFETY; VALVES;DURING OPERATIONiWITH' BOTHSTEAMl GENERATORS."iThefextstingititie%picifiesttriptsetting;1imitsJbased bnitheTnumberioffinoperableisafetMalvesNThisititielappearsiin thelindexito^

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Safety Analysis

-The proposed change described above shall be deemed to involve a significant l

hazards consideration if there is a positive finding in any one of the following areas:

1.

Will operation of the tacility in accordance with.this proposed l

change involve a significant increase in the probability or consequences of an accident previously evaluated?-

Response

No The proposed change to increase the as-found setpoint tolerance of-the Main Steam Safety Valves (MSSVs) to +2%/-3% maintains safety analysis requirements.

Because the upper limit lift pressures are higher, peak primary and secondary pressures are affected.

However, reanalyses of the limiting overpressure events, which are-the Loss of Condenser Vacuum (LOCV) and Feedwater Line Break'(FWLB),

demonstrate that the proposed upper limits do not significantly 1

affect peak primary or secondary pressures.

Therefore, the proposed upper limits maintain the MSSVs within safety analysis limits.

j Also, margin between the as-left setpoints and the upper limit of the as-found setpoint tolerance is maintained by the proposed i

footnote to Limiting Condition For Operation 3.7.1.1 and Table 3.7-1.

i If the MSSVs are set below the upper limit lift pressures, acceptable overpressure results are obtained.

Therefore, lowering i

the minimum allowable lift pressure to -3% below each setpoint-maintains valve setpoint staggering, safety analysis requirements, and sufficient margin between MSSV lift pressures and peak operating pressure. Also, a setpoint tolerance of -3% for the lowest set pair of valves maintains the current dose assumption associated with a Steam Generator Tube Rupture.

i

')

The proposed as-fomd setpoints have a marginal effect on transient' Departure from h ieate Boiling Ratio (DNBR). However, TS 3/4.2.4

.l reserves adequate DNBR overpower margin to ensure specified-i acceptable fuel design limits are not exceeded in the event of an Anticipated Operational Occurrence. The limiting required overpower margin is not adversely affected by this proposed change to MSSV setpoints.

Theleii s t fng'Habl ei3; 7 F2Qrosi dei 7appFopri atFal l sabli]yilde QfR the LinearJPower-High(Trip;withlinoperableLMSSVstrelativeito values p roVi ded ! b'y;Combu sti on? Eng i neeri ng T (CE)? fo riaRos s fof; Coriden;sef 5

1 9

Vacuhm wi th i a f S i ngl e 2 Fa i l u rel(wh i ch M sithsil ki ti ngl ~ ehn t )fas sumi ng i

~

MSSysjhavelaisetpointjtolerance?offupitoj+2%(

l Because this change still requires MSSVs to be set within safety analysis limits, there is no significant increase in the probability or-consequences of a previously evaluated accident.

The change to ACTION statement a requires entry into HOT SHUTDOWN conditions within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> instead of COLD SHUTDOWN within 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

. Reducing the completion time to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is more conservative than the existing requirements.

Furthermore, the MSSVs are not required to be OPERABLE in HOT SHUTDOWN.

Therefore, there is no significant 1

increase in the probability or consequences of a previously evaluated accident due to this change.

Revhing the title Of ech:n 2 of T:bk 3.7 2 to "M=i :: Alh=ble Study St:t P=:r" require reducti= cf Study St:t Ther=1 P= r 5 t=d of red =ti= cf lin=r p=:r high trip =tpoint when := Or

=r: MSSY: Or 6 perbk.

The :1h=ble p=:r v:hn cr: b= d =

=ffici=t Overprc=ur: mitig:ti= =d d =y h=t c==:1 =p=itic for the nt:b r of Oper:bk MSSW.

Red =ing th: 0,l h=bk :t=dy stat p=:r: frw =hting v:h : pr=id= nrgh fer p=:r l

bdicti= crr r =d i: =r

===r=the th= =hth; cih=bh b$ 3

t=dy :ht: p=:r =ke.

R =ter trip f;r =:rpr = r ev=h h

=intched through : high prc=;rher prc=;r trip. ?=ly:h of the Central Ek:=t A:=:bly (CEA) Ejecti= =d Withdr=:1

==h hitiated at red =ed p=:r hvek d==:tr:t= =ffici=: relief

p=itic with = =1 trip =tpchu.

Therefor, there b n; signifi =t her = : h the prchbility Or :==q===

cf pr=ic=ly :=l=ted = id=t det to thh th=ge.

The additional ACTION statement is a clarification to provide more explicit guidance to the operators for all configurations of inoperable MSSVs. Therefore, this change does not involve a significant increase in the probability or consequences of a previously evaluated accident.

Deleting the orifice size column from Table 3.7-1 is an editorial change only. This information is not used by the operators, nor do they have any control over MSSV orifice size. Therefore, removing this information does not significantly increase the probability or consequences of a previously evaluated accident.

2.

Will operation of the facility in accordance with this proposed change create the possibility of a new or different type of accident from any accident previously evaluated?

Response

No t

MSSVs are designed to provide overpressure protection and decay heat l

removal during design basis events. Therefore, widening.the as-i found setpoint tolerance to +2%/-3% for the MSSVs affects only those previously evaluated events which require MSSV actuation. The only-effect MSSV setpoints have on normal plant operation is inadvertent opening of a valve due to a low setpoint. The minimum lift pressure of 1067 psia is sufficiently higher than peak secondary operating pressures so that the probability of inadvertent MSSV opening is not increased. Therefore, this proposed change will not create the possibility of a new or different type of accident from any accident previously evaluated.

Requiring HOT SHUTDOWN entry instead of COLD SHUTDOWN entry in Action a-is acceptable because. there is no credible event different from any previously evaluated requiring MSSV operation in HOT a

. SHUTDOWN. Therefore, this proposed change will not create the possibility of a new or different type of accident from any accident previously evaluated.

Requiring reduced steady state poveer level:..ith one or more 4noperaMe-MSSV instead of redueing linear poveer level high trip setteint; is accc: table because react +r trip for everpressurization events occurs on ligh pressurizer pre;;ure for all events.

For the GEA-f-jection or WithdFavtal everFts, Suf-ficient r0li0f capacity is maintained-by cperat4ng according -te Tabic 3.7 2 ith normal high power trip setpoints. A trip on reduced high linear povser is gW7 unnecessaryr-Normal administ+ative controls provide reasonable assurance that the-power li its for operation <;i-th INOPERABLE MSSV; m

are not exceedede-Therefore, t4cre is no possibi4ity of a nev or different type of accident frem any accident previously evaluatedr-The additional action statement to require a mode reduction when less than five MSSVs are OPERABLE for any steam generator is a clarification to provide explicit guidance to the operators for all configurations of inoperable MSSVs.

This is more conservative than the existing requirements.

Therefore, this change does not create the possibility of a new or different type of accident from those previously evaluated.

Deleting the orifice size column from Table 3.7-1 is an editorial change only. This information is not used by the operators, nor do they have any control over MSSV orifice size. Therefore, removing this information does not create the possibility of a new or different type of accident from those that have been previously evaluated.

3.

Will operation of the facility according to this proposed change involve a significant reduction in a margin of safety?

Response

No The only margin of safety affected by this change is the increase in peak primary and secondary pressure due to raising the upper limit of allowable lift pressures. The limiting overpressure events, FWLB and LOCV were reanalyzed with the proposed upper limits and peak primary and secondary pressures remain within design limits. The exi s ti n glTabl e 131712 fp rovi d eM: a pp ro p ri a teFal l owabl eVilues~for1the Linear Power-High: Trip with inoperable MSSVstrelativeltosvalues 5,R,1 provided by CE for a loss (of Condenser Vacuum withf aESinglelFailure (whichlis thellimitingfevent)iassumi_ng LMSSVsihavefassetpoin_t" tolerance'offup!toi+2%. Therefore;'there is no"significant" reduction ~in'a~ margin ~6f safety.

The change to a +2%/-3% expanded as-found setpoint tolerance maintains safety analysis requirements. The change requiring HOT SHUTDOWN entry instead of COLD SHUTDOWN entry is more appropriate than the existing specification. -The-c4ange requiving,1-veduc-t4en in-steady state pcv;cr level instead of reducing the li near poveer 59I,1 level M h-t+ip setpcint cont 4nue: te aintain the plant at a poveer 9

level based en the operability of MSSV;.

The additional ACTION

_g.

statement is a clarification to provide explicit guidance to the r

operators for all configurations of inoperable MSSVs.

Deleting the orifice size column from Table 3.7-1 is an editorial change only.

s Therefore, there is no significant reduction in a margin of safety as a result of this change.

Safety and Sionificant Hazards Determination Based on the above Safety Analysis, it is concluded that:

1) the proposed change does not constitute a significant hazards consideration as defined by 10CFR50.92; 2)there is reasonable assurance that the health and safety of the public will not be endangered by the proposed change; and 3) this action will not result in a condition which significantly alters the impact of the station on the environment as described in the NRC Final Environmental Statement.

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