ML17331B329

Proposed Tech Specs Re Increase of Allowable Tolerances for Main Steam Safety Valves

ML17331B329
Person / Time
Site:	Cook
Issue date:	03/29/1994
From:	INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:
Shared Package
ML17331B327	List: ML17331B325 ML17331B329
References
NUDOCS 9404040079
Download: ML17331B329 (25)

Text

ATTACHMENT 1 to AEP:NRC:1169B EXISTING TECHNICAL SPECIFICATION PAGES MARKED-UP TO REFLECT PROPOSED CHANGES 9404040079 940529 05000515 PDR 'ADOCK PDR I

4, SSEMS 3 4.7. B CYCLE SAFE VALVES LIMITING CONDITION FOR OPERATION 3.7.1.1 All main steam line code safety valves associated with each steam generator shall be OPERABLE.

ACTION'.

With 4 reactor coolant loops and associated steam generators in operation and with one or more main steam line code safet valves inoperable, operation in MODES 1, 2 and 3 n proceed provided, that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable valve is restored to OPERABLE status or the Power Range Neutron Flux High Setpoint trip is reduced per Table 3.7-1; otherwise, 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 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 />.

b. With 3 reactor coolant loops and associated steam generators in

'peration and with one or more main steam line code safety valves associated with an operating loop inoperable, operation in MODE 3 may proceed provided, that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable valve is restored to OPERABLE status or the reactor trip breakers are opened; otherwise, be in COLD SHUTDOWN within the next 30 hours.

c. The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE RE UIREMENTS

4. 7. 1, 1 No=addi~na~~eiLLance~quirements~th~han~ose-r equipped-by-

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~ COOK NUCLEAR PLANT - UNIT 1 AMENDMENT NO. 444, ].64

n

a. BV'lp $ 065 paig 16 in.

ho BV 16 $ 0CS peig 16 in.

I oi BV-2P $ 075 paig 16 in.

do BV-0 $ 075 psig 16 in.

g's SV-3 iOQ5 paig 16 in.

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• The l lt sett ng pressure shall aorresp9pd to aabient oonditiona noaina1 operating tewperature and pressure.'i oC the valve at s(a'...<<A.

m~ t eye 7 V %c-The OPQAIILZ.Y of the aaron steal Line code saf~sy va ves ensures that the secondary sysssa pressure vill be Limited to vithin its design pressure of L085 psig during s4 moss severe anticipated syssea opera-

-'onal ranskens. The aaxi~ relieving cayacity is associated v'h s~bine t iy froa LOOi RATH 'QaLSLL RNEk coincident vith an assuaged '.oss of condenser heat sink <i. ~ ., no steaa bypass to she condenser).

The syecified valve lift settings ancL relieving cayacis'es are in accordance vith she requireaants of Section lZZ of she AS'ailer Pressure Code, 1971 Edition. The total relieving capacity for all valves and on a o she ster nes 5 17, 153, l00 lba/hr vhich is ayyroxhaately of the total secondary stern flov of 14,110,000 lbe/hr at 100%

RATED THERMAL PO4UL. A ai~ f ot 2 OPXRAILX safety valves yer oyerabL ~

s sake gene ra to r ensures shat suf iciens relieving cayac sy is i avail 12'ercent Le for the allovable THERthL K%EL reasriction in Table 3.7-1.

C STARTUP and/or POSE OPERATZM is allovable vish safety val inoyerabLe vishin she Limitations of she ACTIN requirasents on the basis of the reduction t.n secondary system% ste48 flov and KR%. PSST repulsed by the reduced reac or tziy settings of sho Pover Range Neutron Flux channeLs. Tho reactor trip setyoknt rechcsions ara derived on -"e foLloving bases:

For 4 Loop oyeration 4here:

52 ~ rechced POSER reactor stay setyoint in percent of RATED TM.¹ V ~ aaxhua number of inoyerable safesy valves per ssaaa L'ne-1, 2 or 3.

X TotaL relieving cayacity of all safety valves per stacks line 4. 284,450 lbs/hour.

Y ~ maxima relieving cayacisy of any one safety valve

~ d57,690 Lbs/hour.

(109) Pover Range Neusron Aux-High Trip Setyoint for 4 Loop operation.

% 3/O'J 1

INSERT A The safety vcBve 1s OPERABLE with a lift setting of +3% about the noa)nal value. Haaever, the safety valve shall be reset to the noa1nal value +I%

whenever feed outside the +1% tolerance.

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/4 7 DT 3 4 7 ~ZPD>NE CYC Sa~ V VNG CONDI ION POR OPERATION 3.7.1.1 All ma'n steam line code sa ety valves associated with each steam generator shall be OPER>ZI~.

~CION:

a ~ With 4 reactor coolant loops and associated steam generatox's operation and with one or more main steam line code .safety valves inoperable, operation in MODES 1, 2 and 3 may proceed provided, that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable valve is restored to OPERABLE status or the Power Range Neutron Plux High Trip Setpoint is reduced per Table 3.7-1; otherwise, 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 COLD SHUTD04%b within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

b. With 3 reactor coolant loops and associ:ated steam generators in operation and with one or more main steam line code safety valves associated with an operating loop inoperable, operation in MODE 3 may proceed provided, that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable ~

valve is restored to OPERABLE sta~~ or the reactor trip breakers are opened; otherwise, be in COLD SHUTDOVH within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

c. The px'ovisions of Specification 3.0.4 are not applicable.

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D. C. COOK - U¹T 2 3/4 7-1 ~DK2K HO. 82

TABLE +H<- ~ 7 STEAN LINE SAFETY VALVES PER LOOP E 314

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II/I

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Lli'T VALVE NNBER - SETTING ORIFICE SllE

a. SV-1 A 1065 psig 16 in

b. SV-1 8 1065 ps ig 16 In.~

c. SV-2 h 1075 psig 16 in.2

d. SV-2 8 1015 psig 16 jn.~

e. SV-3 1085 psig 16 ln.~

~e Af~sa Zing pressure shall correspond to Nabient conditions of the valve at nNIinal operating tceparaturn.and pressure.

3/4.5 PtERG&W CORE CQOLIi6 SYSi c..S 3/4. 5. I ACCUMULATORS The OP~QASILITY cf each RCS accumulator ensures that a sufficient volume af boratact ~ater will be immediately forced inta the reactor care through each cf the calct legs fn the event t.'ie RCS pressure fails below the pressure cf the acc~iators. Thfs initial surge cf water inta the core provides the fnftfa]

cooling mechanfsm during Iar ~e RCS pipe ruptures.

The limits on accumulator volume, baron cancantratian and pressure ensure that, the assumptfans used for accumuiatoi injectfcn in the safety analysfs are met.

The accumulator power cperatect isclatfon valves are cansiderect ta be "operating bypasses" fn the cantex. cf IE"-"- Std. 279-1971, which requires Oat bypasses of a protec:ive function be removed automatically whenever permissive conditions are not met. In actctftfcn, as these accumulator fsolatian valves fafl ta meet single failure criteria, removal of power ta the valves is requfred.

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The limits t'or operatian with an ac=viator inoperable fcr any reason except an fsolaticn valve closed minimizes the tfme exposure of the plant,ta a LQCA event cc=urring cancurrent with failure cf an additional accumulator which may resul fn unacceptable peak ciadaing temperatures. If a closect isolation valve Cannot be fmmectiately opened, the full Caaability Of Cne aC"umuiatar fS nat available anct prompt ac-ian is required to place the reactor in a made ~here t:iis capability is nat required.

3/<.5.2 anct 3/4.5.3 EC~A SUBSYSiB5 The OPLRABILiTY cf twc fndeaenctent BC~A subsystems ensures 'iat sufficient emergency care c"cling capaaility will be available in the event of a LQCA assuming ie less cf one subsystem thrcugn any single aiiure c"nsideraticn.

":it.'ier suasystam caeratfng in canjuncticn wi i ".e accumulators is capable clyde c suaplying sufffcfent care coal fng ta limit the peak ciactding camaeratures <<i".h'n acclptable Iimiw far ail pcstulatac break sizes ranging fran the double enaect break of the largest RCS caid leg pipe downward. In aaditicn, each KD subsystem provictes Iong erm cars c"cling caaaaiIity in the reef .aiatfcn made during the accident. rec"very period.

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0. C. CQGK - UNIT 2 8 3/4 ~1 Amendment .'to. 39

4.7 3 4.7.

3 4.7. V VX5 The OPERABILITY oj tho aain aeoaa LSno coda aafoty v'alvoa omruroa chat tho uocondazy Iyleae yroagaro vSLL bo liaitod ta within 119% of Sta daaign proaaara ef 10IS yaS4 darin4 tha seat severe anticipated eyataa operational tranaione. The Iaxiaa roliavin4 eayaciey Sa aaaociatad vith a carbine triy frol 100% RATZD TRXRQL 8$ XR caincidane arith an aaa~d loca of colIdlInaar haae aiokc (S ~ ~ ~ ac44$ by$ 4aa eo the aondanaor)

The epocifiad valm lift oatein41 anal relieving cayacitiea are Sn accordanco vith the rapairewaea of Section ZZX of the ANC Ieilar ancL Praaaaro Coda, I'571 XtKtion The tatbL roLSavin4 vtIa on

~Sty of all Nafoty

~ the aetna linea Sa 17 LS3 400 lba/hr which Sa at Laaae 195

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percent of the aaxiaua Iecondary ataaa flee rasa at 100'ATZO TBLRIAL POMZR. A ~~m of 2 OPXRJOLZ safety valvoa Par seaaa 4onaratar onaaraa that, oafficiont rolSovtng capacity Sa availablo for the aLLevabla.tKStQI.

PORK roatziceion Sn Table 3.7 l.

5TAR?UP and/or PCICR OHSATZON Sa allowable arith aafoey valvula S~rabla &thin the LSaitatieea of tha ACTION zecpairaeonta oa the basis ed tha teduasiae ia seeaedaty systae stead Ree stet 'DRRlfAL yOQUt required by the seduced raaetsr tt'iy satsisgs ed the yeeer yeege Flue eltatestls. tha steerer tsiy setyeiee raduesiees are desired ea the folly baaaa:

Fer 4 leep eyoratioo x (IOO)

%hera 5P ~ e4sa4 reactor eziy ac@cine SI Parcane of NATQ XEKiQÃAL NQLR V ~ R@RSIRR 5LRsh4r of SnayParQbla aafaty valvula par aeaaB XCsa

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A.r X~ CseaL LSD relieving eayaeiey of all aafasy valvaa Par SN Iba. jheaea ~ 4,2N.450 ataxia w I T ~ aaailem relieving capacity af any aae aafaey vaL~

Sa Lba./hear SS7, HO 100 Peter lLaago Noaeren PLY @4h TrSII 5aeyeins fer 4 leg eyaraeion COOK NUCLXAR PLANT ~ %GT 2 I 3/4 7 1 ~g~gggg Io. Ig, 134

INSGtT I The safety @abc 1s OPERABLE wfth a lift setting of +3% about the n~~nal value. However, the safety valve shall be reset to the noehnal value +1%

whenever fegct outsfde the +1% tolerance.

ATTACHMENT 2 to AEP:NRC:1169B PROPOSED REVISED TECHNICAL SPECIFICATIONS PAGES

0 3 4.7 PLANT SYSTEMS 3 4.7e1 TURBINE CYCLE SAFETY VALVES LIMITING CONDITION FOR OPERATION 3.7.1.1 All main steam line code safety valves associated with each steam generator shall be 'OPERABLE.

APPLICABILITY: Modes 1, 2 and 3.

ACTION:

a. With 4 reactor coolant loops and associated steam generators in operation and with one or more main steam line code safety valves inoperable, operation in MODES l, 2 and 3 nap proceed provided th,at within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable valve i.s restored to OPERABLE status or the Power Range Neutron Flux High Setpoint trip is reduced per Table 3.7-1; otherwise, be in at least HOT STANDBY wi.thin 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 />.

b. With 3 reactor coolant loops and associated steam generators in operation and with one or more main steam line code safety valves associated with an operating loop inoperable, operation in MODE 3 may proceed provided, that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable valve is restored to OPERABLE status or the reactor trip breakers are opened; otherwise, be in COLD SHUTDOWN within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

c. The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE RE UIREMENTS 4.7.1.1 Each main steam line code safety valve shall be demonstrated OPERABLE in accordance with Specification 4.0.5 and with lift settings as shown in Table 4.7-1. The safety valve shall be reset to the nominal value flXwhenever found outside the J1X tolerance.

COOK NUCLEAR PLANT - UNIT 1 AMENDMENT NO. XRO, 464

TABLE 4.7-1 STEAM LINE SAFETY VALVES PER LOOP

+34

• II VALVE NUMBER LIFT SETTING ORIFICE SIZE

a. SV-lA 1065 psig 16 in. 2

b. SV-1B 1065 psig 16 in. 2

c. SV-2A 1075 psig 16 in. 2 SV-2B 1075 psig 16 in. 2

e. SV-3 1085 psig 16 in. 2

• The lift setting pressure shall correspond to ambient conditions of the valve at nominal operating temperature and pressure.

COOK NUCLEAR PLANT - UNIT 1 3/4 7-4 AMENDMENT NO. 4RO

3 4.7 PLANT SYSTEMS BASES 3 4.7.1 TURBINE CYCLE 3 4.7.1.1 SAFETY VALVES The OPERABILITY of the main steam line code safety valves ensures that the secondary system pressure will be limited to within 110X of its design pressure of 1085 psig during the most severe anticipated system operational transient.

The maximum relieving capacity is associated with a turbine trip from lOOX RATED THERMAL POWER coincident with an assumed loss of condenser heat sink (i.e., no steam bypass to the condenser).

The specified valve lift of settings and relieving capacities are in Section III of the ASME Boiler and Pressure accordance with the requirements Code, 1971 Edition. The safety valve is OPERABLE with a lift reset setting of +3K to the nominal about the nominal value. However, the safety valve shall be value +1K whenever found outside the +1X tolerance. The total relieving capacity for all valves on all of the steam lines is 17,153,800 lbs/hr which is approximately 121 percent of the total secondary steam flow of 14,120,000 lbs/hr at 100X RATED THERMAL POWER. A minimum of 2 OPERABLE safety valves per operable steam generator ensures that sufficient relieving capacity is available for the allowable THERMAL POWER restriction in Table 3.7-1.

STARTUP and/or POWER OPERATION is allowable with safety valves inoperable within the limitations of the ACTION requirements on the basis of the reduction in secondary system steam flow and THERMAL POWER required by the reduced reactor trip settings of the Power Range Neutron Flux channels. The reactor trip setpoint reductions are derived on the following bases:

For 4 loop operation X

Where:

SP - reduced reactor trip setpoint in percent of RATED THERMAL POWER V - maximum number of inoperable safety valves per steam line 1, 2 01 3 ~

X Total relieving capacity of all safety valves per steam line 4,288,450 lbs/hour.

Y Maximum relieving capacity of any one safety valve 857,690 lbs/hour (109) - Power Range Neutron Flux-High Trip Setpoint for 4 loop operation.

COOK NUCLEAR PLANT - UNIT 1 B 3/4 7-1 AMENDMENT NO.

EMERGENCY CORE COOLING SYSTEMS ECCS SUBSYSTEMS Tg > 350 F LIMITING CONDITION FOR OPERATION 3.5.2 Two independent ECCS subsystems shall be OPERABLE with each subsystem comprised of:

a. One OPERABLE centrifugal charging pump,

b. One OPERABLE safety injection pump c ~ One OPERABLE residual heat removal heat exchanger,

d. One OPERABLE residual heat removal pump,

e. An OPERABLE flow path capable of taking suction from the refueling water storage tank on a safety injection signal and transferring suction to the containment sump during the recirculation phase of operation.

f. All safety injection cross-tie valves open.

APPLICABILITY: MODES 1, 2, and 3.

ACTION:

a ~ With one ECCS subsystem inoperable, restore the inoperable subsystem to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

b. With a safety injection cross-tie valve closed, restore the cross-tie valve to the open position or reduce the core power level to less than or equal to 3250 MW within one hour. Specification 3.0.4 does not apply.

C. Xn the event the ECCS is actnated and injects water into the Reactor Coolant System, a Special Report shall be prepared and submitted to the Commission pursuant to Specification 6.9.2 within 90 days describing the circumstances of the actuation and the total accumulated actuation cycles to date.

COOK NUCLEAR PLANT - UNIT 2 3/4 5-3 AMENDMENT NO.

3 4.7 PLANT SYSTEMS 3 4.7.1 TURBINE CYCLE SAFETY VALVES LIMITING CONDITION FOR OPERATION 3.7.1.1 All main steam line code safety valves associated with each steam generator shall be OPERABLE.

APPLICABILITY: Modes 1, 2 and 3.

ACTION:

a. With 4 reactor coolant loops and associated steam generators in operation and with one or more main steam line code safety valves inoperable, operation in MODES 1, 2 and 3 may proceed provided, that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable valve is restored to OPERABLE status or the Power Range Neutron Flux High Setpoint trip is reduced per Table 3.7-1; otherwise, 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 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 />.

b. With 3 reactor coolant loops and associated steam generators in operation and with one or more main steam line code safety valves associated with an operating loop inoperable, operation in MODE 3 may proceed provided, that within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, either the inoperable valve is restored to OPERABLE status or the reactor trip breakers are opened; otherwise, be in COLD SHUTDOWN within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE RE UIREMENTS 4.7.1.1 Each main steam line code safety valve shall be demonstrated OPERABLE in accordance with Specification 4.0.5 and with lift settings as shown in Table 4.7-1. The safety valve shall be reset to the nominal value +1X whenever found outside the ~1X tolerance.

COOK NUCLEAR PLANT - UNIT 2 3/4 7-1 AMENDMENT NO. 82,

TABLE 4.7-1 STEAM LINE SAFETY VALVES PER LOOP VALVE NUMBER LIFT SETTING +34' ORIFICE SIZE

a. SV-1A 1065 psig 16 in. 2

b. SV-1B 1065 psig 16 in. 2

c. SV-2A 1075 psig 16 in. 2 SV-2B 1075 psig 16 in. 2

e. SV-3 1085 psig 16 in. 2

• The lift setting pressure shall correspond to ambient conditions of the valve at nominal operating temperature and pressure.

COOK NUCLEAR PLANT UNIT 2 3/4 7-4 AMENDMENT NO.

3 4.5 EMERGENCY CORE COOLING SYSTEMS BASES 3 4.5.1 ACCUMULATORS The OPERABILITY of each RCS accumulator ensures that a sufficient volume of borated water will be immediately forced into the reactor core through each of the cold legs in the event the RCS pressure falls below the pressure of the accumulators. This initial surge of water into the core provides the initial cooling mechanism during large RCS pipe ruptures.

The limits on accumulator volume, boron concentration and pressure ensure that the assumptions used for accumulator injection in the safety analysis are met.

The accumulator power operated isolation valves are considered to be "operating bypasses" in the context of ZEEE Std. 279-1971, which requires that bypasses of a protective function be removed automatically whenever permissive conditions are not met. In addition, as these accumulator isolation valves fail to meet single failure criteria, removal of power to the valves is required.

~I The limits for operation with an accumulator inoperable for any reason except an.

isolation valve closed minimizes the time exposure of the plant to a LOCA event occurring concurrent with failure of an additional accumulator which may result in unacceptable peak cladding temperatures. If a closed isolation valve cannot be immediately opened, the full capability of one accumulator is not available and prompt action is required to place the reactor in a mode where this capability is not required.

3 4.5.2 and 3 4.5.3 ECCS SUBSYSTEMS The OPERABILITY of two independent ECCS subsystems ensures that sufficient emergency core cooling capability will be available in the event of a LOCA assuming the loss of one subsystem through any single failure consideration.

Either subsystem operating in conjunction with the accumulators is capable of supplying sufficient core cooling to limit the peak cladding temperatures within acceptable limits for all postulated break sizes ranging from the double ended break of the largest RCS cold leg pipe downward. Zn addition, each ECCS subsystem provides long term core cooling capability in the recirculation mode during the accident recovery period.

If a safety injection cross-tie valve is closed, safety injection would be limited to two lines assuming the loss of one safety injection subsystem through a single failure consideration. The resulting lowered flow requires a decrease in THERMAL POWER to limit the peak clad temperature within acceptable limits in the event of a postulated small break LOCA.

COOK NUCLEAR PLANT UNIT 2 B 3/4 5-1 AMENDMENT NO.

~'

3 4.7 PLANT SYSTEMS BASES 3 4.7.1 TURBINE CYCLE 3 4.7.1.1 SAFETY VALVES The OPERABILITY of the main steam line code safety valves ensures that the secondary system pressure will be limited to within 110% of its design pressure of 1085 psig during the most severe anticipated system operational transient.

The maximum relieving capacity is associated with a turbine trip from 100% RATED THERMAL POWER coincident with an assumed loss of condenser heat sink (i.e., no steam bypass to the condenser).

The specified valve lift settings and relieving capacities are in Section ZZI of the ASME Boiler and Pressure accordance with the requirements of Code, 1971 Edition. The safety valve is OPERABLE with a lift setting of +3%

to the nominal about the nominal value. However, the safety valve shall be reset value +1% whenever found outside the +1% tolerance. The total relieving capacity of all safety valves on all of the steam lines is 17,153,800 lbs/hr which is at least 105 percent of the maximum secondary steam flow rate at 100% RATED THERMAL POWER. A minimum of 2 OPERABLE safety valves per steam generator ensures that sufficient relieving capacity is available for the allowable THERMAL POWER restriction in Table 3. 7-1.

STARTUP and/or POWER OPERATION is allowable with safety valves inoperable within the limitations of the ACTION requirements on the basis of the reduction in secondary system steam flow and THERMAL POWER required by the reduced reactor trip settings of the Power Range Neutron Flux channels. The reactor trip setpoint reductions are derived on the following bases:

For 4 loop operation X

Where:

sp reduced reactor trip setpoint in percent of RATED THERMAL POWER maximum number of inoperable safety valves per steam line total relieving capacity of all safety valves per steam line in lbs./hours = 4,288,450 maximum relieving capacity of any one safety valve in lbs./hour = 857,690 109 Power Range Neutron Flux-High Trip Setpoint for 4 loop operation COOK NUCLEAR PLANT UNIT 2 B 3/4 7-1 AMENDMENT NO. 82 i 434