Text

Application for Amend to License NPF-62,changing Tech Spec 3/4.3.4.1, ATWS Recirculation Pump Trip Sys Instrumentation
	ML20072Q505
Person / Time
Site:	Clinton
Issue date:	12/17/1990
From:	Jamila Perry; ILLINOIS POWER CO.
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20072Q508	List: JSP-959-90, Application for Amend to License NPF-62,changing Tech Spec 3/4.3.4.1, ATWS Recirculation Pump Trip Sys Instrumentation; U-601766, Proposed Tech Spec 3/4.3.4.1, ATWS Recirculation Pump Trip Sys Instrumentation;
References
	JSP-0959-90, JSP-959-90, U-601766, NUDOCS 9012240096
	Download: ML20072Q505 (12)
	v • d • e

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'U-601766 L4 7-9 0 ( 12-17. ) -LP ILLINDIS POWER 88.100e CLINTON POWEH STATION, P.O. BOX '678, CLINTON. ILLINOIS 61727 0678. TELEPHONE (217) 935 8881 i

.JSP-0959-90 December 17, 1990

(

10CFR50.90 i

i Docket No. 50-461 Nuclear. Regulatory Commission Document Control Desk Washington, D.C. .20555

Subject:

Clinton Power Station Proposed Amendment of Facility Operatina License No. NPF-62

Dear Sir:

Pursuant to 10CFR50.90, Illinois-Power Company (IP) hereby applies for amendment of Facility Operating License No. NPF-62, Appendix A - Technical ~

Specifications, for Clinton Power Station-(CPS). This request consists of proposed changes to Technical Specification 3/4.3.4.1, "ATWS Recirculation Pump Trip System Instrumentation." For each of those proposed changes, a description, the associated justification (including a Basis for No Significant Hazards Consideration), and marked-up copies of pages from the current Technical Specifications:are provided in Attachment 2. In addition, an. affidavit supporting the facts set forth in this letter and:its attachments is provided in Attachment 1.

IP has reviewed the proposed changes against the i criteria of 10CFR51.22 for categorical exclusion fromL l environmental impact considerations. The proposed changes do not involve a significant hazards-consideration, or significantly increase the amounts or change the types of effluents that may be released offsite, nor do they significantly' increase individual or Li cumulative occupational radiation exposures. Based on the foregoing, IP concludes that the proposed changes meet the criteria given in 10CFR51.22(c) (9) for a1 categorical exclusion from the requirement for an Environmental. Impact Statement. )

'I 9012240096 901217 DR ADOCK0500882 0 01-

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Sincerely yours,,

l J. ;S. Perry , , l ce= President' ;

1 DAS/alh Attachments cc: Regional Administrator, Region-III,'USNRC- ,.

.NRC>Clinton Licensing Project.. Manager.- '!

NRC Resident Office'~ '

.r-Illinois Department of Nuclear Safety.l i

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Atthchmsnt 1 'l to U-601766 STATE OF ILLINOI3 ;

COUNTY OF DEWITT J. Stephen Perry, being first duly sworn,. deposes and- ,

says:. That he is Vice President of Illinois' Power Company; that the application for amendment-of Facility ,

operating License NPF 62~has-been prepared under his supervision and direction; that he knows the contents thereof; and that to the best'of his knowledge and belief ,

said application and the facts' contained therein are true-and correct. 4 DATED: This 87- day of December 1990.

Signed: h ,b h -

StephenPerry6 Subscribed and sworn to before me this IT day 'of December 1990.

b l&(& h, O W Notary Public.

y. ..

"0FFICIAL SEAL' ;;

[l Sharon E. Harts - i l Notary Public, State of Ilhnos . ,

l ll My Commission Expires 3/9/91: ll t

i

Attachmsnt 2 l

to U-601766 Attachment 2 The following package comprises Attachment 2.

LS-89-021 l

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.l f# U ' U 6017 66 :

LS 89.'021

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_1 Backcround .

Clinton Power Station (CPS) Technical Specification 3/4.3.4.1, "ATWS-Recirculation Pump _-Trip System Instrumentation," addresses the operability of the instrumentation provided to automatically initiate the Anticipated Transient Without Scram Recirculation Pump Trip (ATWS RPT) system.. As-stated-in the Bases for this Technical Specification the ATWS RPT system provides a means of limiting the '-

consequences __ of- an unlikely. occurrence of a failure to scram during !

an anticipated transient. Trip of the recirculation pumps from 100 percent to zero speed is needed-to limit the initial reactor vessel

_ pressure rise and;to reduce the steam blowdown to.the suppression- ,

pool (by reducing reactor power) in the unlikely event that an

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anticipated transient without scram (ATWS) occurs. ~ Additionally, the ATWS RPT system is installed ~in order to comply with the requirements of 100FR50.62.

i The logic for the ATWS-RPT instrumentation is non safety related and consists of four reactor vessel. pressure channels and four reactor vessel water level channels arranged in two separate trip systems . ;

(two reactor proccuro channelsfand two reactor water level channels !

in each trip system). A trip of both reactor pressure channels nr ; -*

both reactor water level channels in one trip system results in an automatic trip of both reactor recirculation pumps and- automatic initiation of the Alternate Rod = Insertion (ARI)' system. Per' design, the ATWS RPT logic is also provided with a_" test"' switch at the trip :

system level to_ allow-bypassing that trip system =for maintenance and:

testing. Placing this switch'in the." test" position causes both reactor pressure channels and both reactor water level: channels'in 1 that trip system to become-inoperable. However, with onec trip system bypassed, automatic initiation of the ATUSpRPT and ARI systems is ,I still possible'from both reactor pressure channels or both reactor water level channels in'the redundant trip system.

Technical Specification 3.3.4.1: requires both reactor pressure channels and both reactor water-level channels.in each trip system to l be operable while in Operational Condition 1. Action "b" of-l Technical Specification 3.3.4.1 currently allows one'. channel in one trip system to be inoperable for up to.48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months ; otherwise, the plant must be in at.least Startup-(Operational Condition-2) within the next' six hours. Additionally, footnote (a) to Technical Specification-Table 3.3.4.1-1, "ATWS Recirculation Pump Trip System _ ..

Instrumentation," allowsLone channel to be placed-in an. inoperable status for up to two hours for required surveillance provided the "

redundant: trip _ system is operable and. monitoring that. parameter.

I Because-of the design of the ATUS RPT instrumentation at CPS, it is

impossible to bypass onlyione channel. LAs described-above,-use of one of the-presently installed ATWS-RPT test switches results in the entire trip-system (both reactor pressureLchannels and both reactor ,

water level channels) being_ inoperable. Footnote'(a) to Technical, ;

g Specification Tablo 3.3.4~.141 and the Action Statements of Technical a L Specification 3.3.4.1 do not currently. address having more than one. '

l channel in one trip system inoperable. Therefore, the following proposed changes to Technical' Specification 3.3.4.1 are being i a

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U + 6017 6 6 -

LS89-021 .,

, Page-2-of.11 - j provided to more closely reflect the- capabilities ~ of the. CPS ATWS RPT l instrumentation design and to allow the use of the'ATWS-RPT trip '

system test switches during Operational Condition 1.

Description of Proposed Changes -!

In accordance with--100FR50.90, the following changes to CPS Technical Specification 3/4.3.4.1, "ATWS Recirculation Pump Trip System: i Instrumentation,"'are being proposed:'

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1) Action "b" is being revised to allow continued plant _ operation'-

when the number of operable channels.is:any number less than?

required by the Minimum;0perable? Channels.per. Trip System:

requirement for one trio system. This_ proposed change will:

require the inoperable channel _(s) to be:placed in the. tripped condition within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . -When the inoperable, channel (s) '

cannot be placed in thestripped condition within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , either.because of an equipment problem;or because this would-cause actuation of the ATWS RPT-system or ARI' system, the plant would-be required to be in at least'Startup (0perationale 4 Condition 2) within_the-next six hours.

This proposed change willipreclude unnecessary plant shutdown. ,

when the logic has been place'd_in a conservative condition'suchi that the inoperable channel (s) will= not' preclude. actuation ,of : 3 that trip system from that parameter ;The proposed _ time limit =. -

(72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months )-is--consistent with the'StandardiTechnical g Specifications and the Technical. Specifications;of other;BWR/6' I plants: when one _ trip system-is~ not capable of providing the.

required actuations.

In addition, an exemption,from the provisions of Technical i Specification 3,0.4 has been added to the proposed Action "b;

This exemption will allow. plant startupLwith one or more l channels inoperable-in one.-trip system.

2) A new. Action Statement, Action ~"c"'cis being-addedLto allow continued plant operation when the number of. operable channels.

is I!nn less than required by the Minimum-Operable. Channels per 4 Trip System requirement for both trio systems. The proposed 1 Action "c" will require one; inoperable; channel;to-be placediin!

the tripped condition-within one' hour. LConsistent with j_

proposed Action "b" above, the.secondsinoperableichannel would i be required to be placed in the-tripped condition within 72 l hours. ,If these requirements cannot be met, either because-of an equipment problem or because this would cause actuation of-the ATWS-RPT system or ARI. system, tho-plant would be required to be in at least Startup-(Operational-Condition 2).within the- 1

- next six -hours.

This proposed change twill also preclude Lunnecessary: plant shutdown when the ATWS RPT logic has been placed in a conservative condition such that the-inoperable channels will 3 not preclude actuation of either trip system from either parameter. The proposed' time limit of one hour'is consistent

U 601766 LS89-021 Page 3 of 11 with the Standard Technical-Specifications when one channel is inoperable in both trip = systems although the Standard Technical =

Specifications require both inoperable channels to be placed in the tripped condition within one hour.

Additionally, an exemption from-the provisions of the Technical Specification 3,0.4 has been added to the proposed Action "c",

This exemption will allow plant startup with one channel inoperable in both trip _ systems.

3) A new Action Statement, Action "d", is being added to address 1 the condition of hat.h trin systems being inoperable for reasons other than addressed by the proposed Action "c". The proposed Action "d" will require at least one trip system to be restored to operable status within one hour or the plant must be in at least Startup (Operational Condition 2) within the next six hours. When one trip system has been restored to operabic status, continued plant operation would be governed by proposed Action "b". This proposed change will provide a very limited period of time to restore the capability of the ATWS RPT instrumentation to effect an automatic trip when required without resulting in unnecessary entry into Technical Specification 3;0.3, This proposed change is identical to the requirements provided in the Standard Technical Specifications and the Technical Specifications of other BWR/6 plants when both trip systems of the ATWS RPT instrumentation are inoperable.

4) Footnote (a) of Technical Specification Table 3,3,4,1-1 is being revised to allow one trio system to be placed in an inoperabic status for up to two hours for required surveillance-when the redundant trip system is operable, As described in the Background section of this request, this proposed change is necessary to allow the use of'the presently installed ATWS RPT trip system test switches during Operational Condition 1.

Justification for Pronosed Channen-The current Action Statements of CPS Technical Specification 3.3.4.1 are overly restrictive with respect to the' CPS design. As described in the Bases for this Technical Specification'and CPS Updated Safety Analysis Report (USAR) Section 7,7,1,25, the ATWS-RPT is a non-safety related system installed to mitigate the potential consequences of a postulated ATWS event. In compilance with 10CFR50,62, the ATWS RPT system functions independently of the nuclear safety-related End of-Cycle- Recirculation Pump Trip (EOC-RPT) system by providing an alternate means of tripping r.he recirculation pump motors and the low frequency motor / generator sets during a postulated.ATWS event, As stated in USAR Section 15.8.1, the probability of an ATUS event is significantly less than the probability of a design basis event. In the extremely remote case that such an event should occur, the ATWS-RPT system will quickly reduce reactor power. Operator action can-also be taken to insert control rods or activate the standby liquid control system and achieve suberiticality independent of control rod insertion.

.U-601766 LS 89 021 Page 4 of 11 As previously discussed, the ATWS RPT lor.lc is arranged in two separate trip systems. Each trip system consists of two reactor vessel water level channels and two reactor vessel pressure channels, A trip of both reactor water level-channels 2r both reactor pressure channels in one trip system results in actuation of that trip system.

Actuation of either trip system is sufficient for complete actuation of the ATWS-RPT and ARI systems.

The current CPS Technical Specifications only address inoperability of one channel in one trip system. The current CPS Technical .

Specifications allow one channel to be inoperable for 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months or the plant must be in at least Startup (Operational Condition 2) within the next six hours. In this configuration, automatic initiation of the ATWS RPT and ARI systems can still be achieved from the remaining' operable trip parameter in the affected trip system or from either operable trip parameter in the redundant trip system.

Prorosed Action "b" The proposed Action "b" would allow continued plant operation with one or more inoperable channels in one trin system. In this ccnfiguration, the redundant trip system would still be fully operable. As a result, the ATWS RET instrumentation is still capable of performing its safety functions in response to either trip parameter (low reactor water level or high reactor pressure) in the redundant trip system. Ilowever, single failure considerations require that continued plant operation be limited.

The proposed Act19n "b" would limit continued plant operation to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , but instead of requiring the plant to be 1n at least Startup within the next six hours at the end of this. time period, .the proposed Action "b" would allow plant operation to continue if the inoperable channel (s) can be placed in the tripped condition without causing actuation of the ATWS-RPT system or ARI system.

l Alternatively, if the inoperable channel (s) cannot.be placed in the I

tripped condition without causing actuation of the ATWS-RPT system or ARI system, the inoperable-channel (s) must he restored to operable status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or the plant must be in at least Startup within the next six hours.

j Continued plant operation for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months with one trip' system I potentially incapable -f actuating from one or both. trip parameters l 1s. justified based upon the -capability of the remaining operable trip L system to provide the required actuations from either trip parameter i

and the low probability-of an event occuring that requires operation of this system, coincident with a single failure,,during this relatively short time period. Additionally, this allowable out of-service time (72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ). is consistent with the time limit prc /ided in the Standard Technical Specifications and the Technical Specifications of other BWR/6 plants when'one trip system is incapable of providing the required actuations. After the inoperable channel (s) has been placed in the tripped condition, the ability of the ATWS-RPT instrumentation to effect an automatic trip from either

i' U 601766 LS 89 021 Page 5 of 11 trip parameter coincident with single failure has been restored, and therefore unlimited plant operation is justified.

Additionally, an exemption from the provisions of Technical i Specification 3,0.4 has been added to the proposed Action'"b". This provision will allow plant startup with one or more channels inoperable in one trip system. As stated above, the redundant trip system would still be fully operable in this configuration and the inoperable channel (s) would be required to be placed in the tripped condition within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . With this proposed change, the Technical Specifications woula att11 provide adequate assurance that the ATWS-RPT instrumentation will perform its required function (s) in the unlikely event of an ATWS event, Moreover, per proposed. Action "b",

system redundancy must be restored within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Therefore, it_ is overly restrictive to prevent entry into Operational Condition 1,with an inoperable channel (s) in one trip system.

,.oDoSed Action "c"

The proposed Action "c" would extend the ability to continue plant operation with Eng channel inoperable in both trin systems. This allowance is provided in the Standard Technical Specifications and other BWR/6 plants' Technical Specifications. In this. case, one inoperable channel would be required to be placed in the tripped.

condition within one hour, This action would restore the ability of the ATWS RPT instrumentation to effect an automatic trip from either trip parameter. However, single failure considerations require that .

continued plant operation be limited. Consistent with proposed Action "b" above, the second inoperable channel would be required to be placed in the tripped condition within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . As discussed above, this subsequent action will restore-the ability of the ATWS-RPT instrumentation to perform its safety functions coincident with a single failure, If these requirements cannot be met, the plant would be required to be in at least Startup within the next six hours.

The proposed allowance for one inoperable channel in both trip systems to exist for one hour is justified based upon -the extremely low probability of an event occurring during this very short time period. (As previously stated, the probability of an ATWS event occurring is significantly less than that of a design basis accident.) Therefore, continued plant operation in this condition for one hour is justified. Additionally,. the ability of the ATUS-RPT instrumentation to actuate when required, coincident with a single failure, is restored-(within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ) after both inoperable channels-have been placed in the tripped condition. Continued,' unlimited plant operation in this condition is therefore justified!

Additionally, an exemption from the provisions of Technical Specification 3.0.4 is included in the proposed Action "c". This provision will allow plant startup with one channel inoperable in both trip systems. As stated above, one inoperable channel would be required to be placed in the tripped condition within one hour'and the second inoperable channel would be required to be placed in the tripped condition within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , These actions provide adequate assurance that the ATWS-RPT instrumentation will be available when k

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LS 89 021 g" Page 6 of 11~

required since_the. probability of an event occurring'that requires ,,

actuation.of this system is extremely small during the.very short 4

, period ~ of time ~ the ATWS RPT inst.rumentation is potentially not:

capable _ of sprovJding the required actuations from both trip -

parameters. After one inoperable channel,has been placed in the' ,j tripped condition (within one hour).--the associated tripqsystem has:

been restored-to_a configuration that:will. provide the required actuations from either trip parameter *. Additionally, the_second

inoperable channel would be required to be'placed in the tripped- ;

condition within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . This will restore . the: ability of both -

trip systems- to effect an' automatic actuation' from eitheritrip -

parameter. Therefore, it.isLoverly-restrictive 1to; prevent entry)into operational-Condition 1 with one= inoperable channel in both trip: _ _

systems, and the proposed exemption from the provisions of Technica1E Specification 3.0.4 is justified.

Pronosed Action "d" t The proposed Action "d" addresses the case in which both trio-svstems. ;

are inoperable for: reasons other than addressed by: proposed. Action "c". -In.this case, the proposed Action "d" requires at lesst one '

trip system to'be restored to operable status within one hour. With j one trip system restored-to. operable status,econtinued plant-operation would b_o governed by proposed Action "b". -If one = trip-s system is;not restored.to operable status within_one hour, the plant must be in at least Startup=within(the next;six hours. Continued plant operation for~one hour with both ATUS RPT trip, systems _.

inoperable is consistent with the-requirements:of the: Standard:

Technical: Specifications and the Technical 1Specif1_ cations of other BWR/6_ plants 7 The- proposed Action ;"_d"L is justified based- on the extremely limited period of: time:that proposed)Actionl"d":will allow:

continued plant operation with -both - ATWS-RPT trip systems: inoperable'-

=

-and the~ extremely low probabilityLof an event occurring that requires actuation of this system during this very short time period.i i

-Footnote (a) to Table 3.3.4.1-1:

The proposed change'to footnotet(a).of Technical Specification Table i 3.3.4'.1-1 is provided to allow:the use.of the~ATWS RPT_ trip system -

test switches'during Operational Condition 1. As_previously- 4 l

discussed, placing one ATWS RPT instrumentation test-switch in the '

test-position causes the= associated trip system (twolreactorspressur'e_

channels and'two' reactor: water levelichannels) to be bypassed; Therefore, when this switch is placed 'in1theitest position, fmix . ij channels of the ATWS RPT instrumentation are. inoperable. As_it is currently worded, footnote (a) only allcws p.ng channel to be; bypassed ,

for rurveillance testing. The-current--footnote is therefore ineffective since,'because of.the circuit. design,:thereLis no physical'way to bypass only one channel in the ATWS RPT logic.

This proposed change will' allow usefof the ATVS-RPT trip-system ~ test

-switches for a limited period of time during Operational Condition 1 by allowing one complete trip system to be bypassed for up to two hours for required surveillance provided-the redundant trip system is operable. Because the redundant trip system would still be capable ~ ,

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U-601766 LS89-021 Page 7 of 11 of actuating the ATWS.RPT and ARI systems from either trip parameter (i.e., high reactor pressure or low reactor water level) during the l l

short period of time allowed by this proposed note, this-proposed '

change is justified.

Basis for No Sicnifiennt HLtnrds Consideration In accordance with 10CFR50.92, a proposed change to the operating license (Technien1 Speelfications) involves no significant hazards considerations if operat:lon of the facility in accordance with the proposed change would not: (1) involve a significant increase in the probability or consequences of any 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 significant reduction in a margin of safety. The proposed changes are evaluated against each of these criteria below.

1) Since these proposed changes do not involve a change to the plant design or operating modes, these proposed changes cannot increase the probability of any accident previously evaluated, The ATWS.RPT instrumentation is provided to mitigate the consequences of a postulated ATWS event, and its failure alone cannot create an accident.

The proposed' change to allow any number of channels in one trip system to be inoperable for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months is justified based upor the abilityaof the redun6c.it. trip system to provide the required actuations from either trip parameter (i.e., low reactor water level or high reactor pressure) and the low probability of an event occurring that requires actuation of this. instrumentation, coincident with a single failure, during this relatively short time period. As presented in USAR Section 15,8.1, the probability of an ATWS event is significantly less than the probability of a design basis l

event. Additionally, the allowance to have one ATWS-RPT trip system potentially incapable of providing the required actuations for up to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months is consistent with the Standard Technical SpecificatLons and the Technical Specifications of othcr BWR/6 plants.

The proposed changes to allow continued plant operation for one hour -with both trip systems inoperable are justified based upon the extremely low probability of an event occurring that requires actuation of this instrumentation during this very short time period. Notwithstanding, restoration would be required (within one hour), such that the ATWS-RPT logic would be restored to a condition in which it is capable of providing l

-automatic actuation from each of its trip parameters (i.e., low reactor water level and high reactor pressure). ~ Moreover, the ,

-proposed Actions would ensure, due to single failure !

considerations, that the redundancy provided by two trip .

systems be restored within a limited time. period. The proposed I changes still require that the capability of both trip systems i be restored within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Otherwise, the plant is required

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U-601766 LS-89 021 Page 8 of 11 to be in at least Startup (Operational Condition 2) within the next six hours.

The proposed exemptions from the provisions of Technical Specification 3.0.4 to allow entry into Operational Condition 1 with an inoperable channel (s) are justified since placing the inoperable channel (s) in the tripped condition places the ATWS-RPT logic in a conservative condition such that the inoperable channel (s) will not preclude actuation of the trip system (s) from the required parameters. Additionally, as discussed above, the allowable out of-service times provided in the proposed Actions provide adequate assurance that the ATUS-RPT instrumentation will be available when required.

The proposed change to footnote (a) nerely allows the use of the presently installed ATWS-RPT trip system test switches to perform required surveillances while in Operational Condition

1. This proposed change still requires that the redundant trip system be operable to provide the required actuations in the unlikely occurrence of an ATWS event during this short time period. Because the use of the test switch is limited to two hours, this proposed change is justified based upon the very low probability of an event occurring that requires actuation of this system, coincident with a single failure, during this very short time period.

Based upon the above, these proposed changes do not significantly increase the probability or the consequences of any accident previously evaluated.

2) These proposed changes do not result in any change to the plant design or operation which could introduce a new failure mode.

Failure of the ATUS-RPT instrumentation alone cannot create an accident. Therefore, these proposed changes cannot create the possibility of a new or different kind of accident from any accident previously evaluated.

3) These proposed changes do not involve a change to the plant design, operation, or setpoints of the ATWS RPT instrumentation. As described in item 1 above, under the proposed changes, the Technical Specifications would continue to provide adequate assurance that the ATWS-RPT instrumentation is available to perfor its intended safety -functions when required. Therefore, these proposed changes do not involve.a significant reduction in the margin of safety.

Based upon the foregoing. IP concludes that these proposed changes do not involve a significant hazards consideration.

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JSP-959-90, Application for Amend to License NPF-62,changing Tech Spec 3/4.3.4.1, ATWS Recirculation Pump Trip Sys Instrumentation

Text

Subject:

Dear Sir:

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