Text

Proposed Tech Specs Re Feedwater/Main Turbine Trip Sys Actuation Instrumentation Design Change
	ML20137W513
Person / Time
Site:	LaSalle
Issue date:	04/14/1997
From:	; COMMONWEALTH EDISON CO.
To:	;
Shared Package
ML20137W510	List: ML20137W507; ML20137W513;
References
	NUDOCS 9704180130
	Download: ML20137W513 (21)
	v • d • e

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ATTACHMENT B PROPOSED AMENDMENTS TO THE LICENSE / TECHNICAL SPECIFICATIONS List of Affected Pages:

NPF-11 NPF-18 3/4 3-86 3/4 3-86 3/4 3-87 3/4 3-87 .

B 3/4 34 B 3/4 34 B 3/4 3-6 B 3/4 3-6 1

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PDR ADOCK 05000373 P PDR 3 ;,s J

o INRTRUMrNTaTTON 3/d.3.A FEEDWATER/ MAIN TUREINE TRYP SYETEM ACTUATTON INSTRUMENTATION LIMT?fNO CONDITION FOR OPERATION 3.3.8 .The feedwater/ main turbine trip system actuation instrumentation channels shown in Table 3.3.8-1 shall be OPERABLE with their trip setpoints set consistent with the values shown in the Trip setpoint column of Table '

3.3.8-2. I 1

APPLICARILITY: OPERATIONAL CONDITION 1.

Acumis -

a. With a feedwater/ main turbine trip system actuation instrumentation l channel trip setpoint less conservative than the value shown in the !

Allowable Values column of Table 3.3.8-2, declare the channel inoperable until the channel is restored to OPERABLE status with its trip setpoint adjusted consistent with the Trip setpoint value.

,' b. With the number of OPERABLE channels one less than that required by f the Minimum OPERABLE Channels per Trip System requirements ;

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1. Within 7 days, either place the inoperable channel in the

. tripped

condition or restore the inoperable channel to OPERABLE status.

2. Otherwise, be in at least STARTUP within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

c. With the number of OPERABLE channels two less than required by the Minimum OPERABLE Channels per Trip System requirement's

1. Within two hours place or verify at least one inoperable channel in the tripped

condition, and restore either inoperable channel to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , or, i

. 2. Be in at least STARTUP within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months . '

l EURVETLLANCE REOUTREMENTE .

4.3.8.1 Each feedwater/ main turbine trip system actuation instrumentation channel shall be demonstrated OPERABLE by the performance of the CHANNEL CHECK, CHANNEL TUNCTIONAL TEST and CHANNEL CALIBRATION operations at the frequencies shown in Table 4.3.8.1-1.

4.3.8.2 LOGIC SYSTEM FUNCTIONAL TESTS and simulated automatic operation of all channels shall be performed at least once per 18 months.

4 An inoperable channel need not be placed in the tripped condition where this would cause the Trip Function to occur.

I LA SALLE - UNIT 1 3/4 3-86 Amendment No. 104 l

ATTACHMENT B PROPOSED AMENDMENTS TO THE LICENSE / TECHNICAL SPECIFICATIONS

-INSERT A TS 3.3.8 Action b:

b. With one or more channels required by Table 3.3.8-1 inoperable:

1. Within two hours, verify sufficient channels remain OPERABLE or tripped

to maintain trip capability, and

2. Within 7 days, either place the inoperable channel (s)in the trip system in the tripped

condition or restore the inoperable channel (s) to OPERABLE status.

c. Otherwise, be in at least STARTUP within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

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TABf2 1.3,8-1 O

FEEDNATER/ MAIN TURBINE TRIP SYSTEM ACTUATION INSTRUMENTATION MINIMUM OPERABLE CHANNELS TRIP FUNCTION PER TRIP SYSTEN

a. Reactor vessel Nater Level-High. Level 8

A channel may be placed in an inoperable status for up to 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months for required surveillance testing without placing the Trip System in the tripped condition.

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l LA SALLE - UNIT 1 3/4 3-87 Amendment No. 104

INSTRUMENTATTON aARER j

i l 3/4.3 G BFit* TOR COMP IsOLATTON COOLTuo EYSTEM ACTUATION T-=mu-m1mTTON i

The reactor core isolation cooling system actuation instrumentation is i 1

provided to initiate actions to assure adequate core cooling in the event of l reactor isolation from its primary heat sink and the loss of feedwater flow to l the reactor vessel without providing actuation of any of the emergency core

cooling equipment.

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specified surveillance intervals and surveillance and maintenance outage ;

I times have been determined in accordance with GENE-770-06-2-A, " Addendum To t

{ Bases for Changes to surveillance Test Intervals and Allowed Out-of-service j 4-Times for selected Instrumentation Technical specifications (BWR RCIC Instrumentation)", December 1992. When a channel is placed in an inoperable status solely for performance of required surveillances, entry into LCo and

']hn h 4

I RCIC initiation capability. required ACTIONS may be delayed, provided the associated function 3/d.3.8 CONTROL ROD WITHDRAW &L et.fler TNCTRUMENTATION The control rod block functions are provided consistent with the requirements of the specifications in section 3/4.1.4, control Rod Program j

' will Controls. The trip logic is arranged so that a trip in any one of the inputs result in a control rod block, l';

specified surveillance intervals and surveillance and'. maintenance outage times have been determined in accordance with NEDC-30851P-A, supplement 1, t

Technical specification Improvement Analysis for BWR Control Rod Block '

Instrumentation", October 1988, and GENE-770-06-1-A, " Bases for Changes to surveillance Test Intervals and Allowed out-of-service Times for selected l Instrumentation Technical specifications", December 1992. When a channel is

", placed in an inoperable status solely for performance of required j j

surveillances, entry into LCO and required ACTIONS may be delayed, provided the associated function maintains Control Rod Block capability. l s

3/4.3.7 MONITORTNd TNCTRUMENTATfDN 3/4.3.7.1 RADTATION MONTTORTNO TMcTRUMENTATION 4

The OPERABILITY of the radiation monitoring instrumentation ensures that:

(1) the radiation levels are continually measured in the areas served by the individual channels, and (2) the alarm or automatic action is initiated when i

the radiation level trip setpoint is exceeded.

specified surveillance intervals and surveillance and maintenance outage times have been determined in accordance with GENE-770-06-1-A, " Bases for i Changes to surveillance Test Intervals and Allowed Out-of-service Times for l selected Instrumentation Technical specifications", December 1992. When a i channel is placed in an inoperable status solely for performance of required surveillances, entry into LCO and required ACTIONS may be delayed, provided j the associated function maintains initiation capability. i l l l

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LA SALLE.- UNIT 1 B 3/4 3-4 Amendment No. 104 i

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ATTACHMENT B PROPOSED AMENDMENTS TO THE LICENSE / TECHNICAL SPECIFICATIONS INSERT B An auxiliary relay contact of Channel A of the RCIC Reactor Vessel Water Level-High, Level 8 instrumentation channelis used as an input to trip Channel C of the Feedwater/ Main Turbine Trip System Actuation Instrumentation. Therefore, the Limiting Condition for Operation and Surveillance Requirements of both TS 3/4.3.5 and 3/4.3.8 are applicable to the RCIC level 8 channel A instrumentation channel.

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INSTRifMENTATION BAEEE \

l 3/d'3.7.10 DetrTrn l i

3/4.3.7.11 '

rYPLOETVE CAE MONTTonfuc i-1mbMrNTATION This instrumentation provides for monitoring (and controlling) the concentrations of potentially explosive gas mixtures in the waste gas holdup system.

3/&.3.7.12 LOOEr-PANT LE+iEriOM E^is rm

The OPERABILITY of the loose-part detection system ensures that sufficient' capability is available to detect loose metallic parts in the primary system and avoid or mitigate damage to primary system components.

allowable out-of-service times and surveillance requirements are consistent The j with the recommendations of Regulatory Guide 1.133, ' Loose-Part Detection ,

Program for the Primary System of Light-Water-Cooled Reactors. * ,

3/a.3.a yrrnwATrn /MATw Prinafur TnTP -

--11 i AcTt1ATIOw TwfTutfwrwtATION i The feedwater/ main turbine trip system actuation instrumentation is provided event to initiate tha feedwater system / main turbine trip system in the of reactor vessel water level egaal to or greater than the level 8 setpoint associated with a feedwater centro 11er failure, to prevent discharge through the safety / relief valve dischargespecified lines. overfilling the re determined in accordance with CDTE-770-06-1-A, surveillance intervals and s " Bases for Changes to surveillance Test *

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i Instrumentation Technical specificatioas*, December 1992. Intervals and A11cwed When a channel is placed surveillances, in an inoperable status solely for performance of required

., entry into LCO and required ACTIONS may be delayed, provided.

actuation capability. maintains Feeduster system / Main Turbine Trip system the associated function

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I LA SALLE - UNIT 1 33/43-6 Amendment No. 104

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l ATTACHMENT B i PROPOSED AMENDMENTS TO THE l

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LICENSE / TECHNICAL SPECIFICATIONS INSERT C - 'l The'four instrument channels are arranged to make a two out of three trip logic. In

- order to eliminate the loss of the reactor vessel water level eight trip due to the loss of l

- either variable leg instrument line for narrow range level instrumentation, trip channel :

C of the level 8 trip logic contains two reactor vessel water level 8 sensor trip relay j contacts. Therefore, trip channel C contains two c!;t.nnels, providing the redundancy 1 i needed to prevent a failure to trip of the feedwater pumps / main turbine due to an j

. instrument line failure. One of the four channels (one of the two channels in trip : l j channel C) is from the Channel A, RCIC reactor vessel water level 6 trip relay, which - :

j is associated with TS 3.3.5. Reactor Core isolation Cooling System Actuation l l j instrumentation.

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Actions b.1'and b.2 are modified by a Note that states that an inoperable channel - ;

need not be placed in the tripped condition where this would cause the Trip Function -l to occur. This note acknowledges that an orderly shutdown per Action c is preferred 1 to the transient that will occur if the trip were actuated. ;

i Action b.1 assures that whatever combination of channels are inoperable, that l automatic trip capability either exists or is restored within two hours, which is sufficient J i

for the operator to take corrective action and takes into account the likelihood of an event requiring actuation of this Trip Function. This will require a minimum of two {

channels Operable or one channel Operable with one channelin the tripped condition in order to satisfy Action b.1. If Action b.1 is satisfied, then Action b.2 is entered. If .

Action b.1 is not satisfied, then Action c must be entered. j l

Action b.2 assures that each inoperable channelis placed in the tripped condition !

l' within 7 days, if each inoperable channelis in the tripped condition or declared 1 . Operable within 7 days, then continued unit operation is allowed, due to the remaining

} redundancy for single instrument failure. If one or more channels are inoperable, and cannot be pieced in the tripped condition or declared Operable within 7 days, then l, Action c must be entered.

E ' An auxiliary relay contact of Channel A of the RCIC Reactor Vessel Water Level-

- High, Level 8 instrumentation channel is used as an input to trip Channel C of the FeedwateiWain Turbine Trip System Actuation Instrumentation. Therefore, the

. - Limiting Condition for Operation and Surveillance Requirements of both TS 3/4.3.5 and 3/4.3.8 are applicable to the RCIC level 8 channel A instrumentation channel.

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. INSTRUMENTATION 3/d.3.B Frrf%fATER /MATN TUReTNF TRTP EYs?EM AL*TtfATION TNf?RE7 MENTATION LYMTTINS CONDTTTON FOP OPERATTON 3.3.8 The feedwater/ main turbine trip system actuatim instrumentation char.&1e shown in Table 3.3.8-1 shall be OPERABLE with their trip setpoints set consistent with the values shown in the Trip setpoint column of Table 3.3.8-2.

APPLIpABILITY: OPERATIONAL CORDITION 2.

'/

ACTION:

a. With a feedwater/ main turbine trip eystem actuation i instrumentation channel trip setpoint less conservative than the {

value shown in the Allowable Values column of Table 3.3.8-2, declare the channel inoperable until the channel is restored to l j

OPERABLE status with its trip setpoint adjusted consistent with l the Trip Se,tpoint t value.

b. With the number of OPERABLE channels one less than that required s by the Minimum OPERABLE Channels per Trip System requirements ,

1) Within 7 days, either place the inoperable. channel in the p6 tripped

condition or restore the inoperable channel to i

pgf 8 I

OPERABLE status.

2) Otherwise, be in at least STARTUP within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months . '

c. With the number of OPERABLE channels two less than required by the Minimum OPERABLE Channels per Trip System requirement:

1) Within two hours place or verify at least one. inoperable channel in the tripped

condition, and restore either inoperable channel to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , or,

2) Be in at least sTARTUP within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

sUPvrTLLANcr REOUTREMENTE 4.3.8.1 Each feedwater/ main turbine trip system actuation instrumentation channel shall be demonstrated OPERABLE by the performance of the CHANNEL CHECK, CHANNEL PUNCTIONAL TEST and CHANNEL CAtIBRATION 4

operations at the frequencies shown in Table 4.3.8.1-1.

4.3.8.2 LOGIC SYSTEM FUNCTIONAL TESTS and simulated automatic operation of all channels shall be performed at least once per 18 months.

i An inoperable channel need not be placed in the tripped condition where this would cause the Trip Function to occur.

S M - UNIT 2 3/4 3-86

, Amendment No. 90

b ATTACHMENTB PROPOSED AMENDMENTS TO THE LICENSE / TECHNICAL SPECIFICATIONS INSERT A TS 3.3.8 Action b:

b. With one or more channels required by Table 3.3.8-1 inoperable:

1. Within two hours, verify sufficient channels remain OPERABLE or tripped

to maintain trip capability, and

2. Within 7 days, either place the inoperable channel (s) in the trip system in the tripped

condition or restore the inoperable channel (s) to OPERABLE status.

c. Otherwise, be in at least STARTUP within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

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Taar_s 3,3,g_1 --

Tf.EDEiaTERZHhlM_TURRIME TRIP SYSTEM ACTUATION IMSTRUMENTATION ,

-MINIMUM OPERABLE CHANNELS TRIP FUNCTIOAf PER TRIP SYSTE3R A. Reactor Vessel Water Level-High, Level 8 y a A channel may be placed in an inoperable status for up to 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months for required surveillance testing without placing the Trip System in,the tripped condition. -

9 LA SALLE - UNIT 2 3/4 3-87 Amendment No. N

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InstauMENTATION e -

names i

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3/4.3.s aricrom come isot aTrow cootinc systew Actt Trow TwstaturwTATrow The reactor core isolation cooling system actuation instrumentation is l

provided to initiate actions to assure adequate core cooling in the event of reactor isolation troa its primary heat sink and the loss of feedwater flow to a

i the reactor vessel without providing actuation of any of the emergency core cooling equipment. '

specified surveillance intervals and surveillance and maintenance outage 4

times have been determined in accordance with GENE-770-06-2-A, ' Addendum to j Bases for Changes to surveillance Test Intervals and Allowed out-of-service j

i Times for selected Instrumentation Technical specifications (BWR RCIC Instrumentation)*, December 1992. When a channel is placed in an inoperable 6 status solely for performance of required surveillances, entry into LCO and required ACTIONS may be delayed, provided the associated function maintains

8 [ RCIC initiation capability.

W .s cowTaot m o n wr T unn m t. armer TwsTnUMrwtATrow i The control rod block functions are provided consistent with the 4

requirements of the specifications in section 3/4.1.4. Control Rod Program l Controls. The trip logic is arranged so that a trip in any one of the inputs will result in a control rod block.

i specified surveillance intervals and surveillance and maintenance outage times have been determined in accordance with NEDC-30851P-A, supplement 1.

" Technical specification Improvement Analysis for BWR Control Rod Block Instrumentation *, October 1988, and GENE-770-06-1-A, " Bases for Changes to surveillance Test Intervals and Allowed out-of-service Times for selected Instrumentation Technical specifications *, December 1992. When a channel is placed in an inoperable status solely for performance of required surveillances, entry into LCO and required ACTIONS may be delayed, provided

the associated function maintains control Rod Block capability.

3/d.3.7 MoufToMTwa TNcTRUMrNTATTou

, 3/4.3.7.1 RADIATIow wowtToRTMC TMETRUMrNTATIow -

i The OPERASILITY of the radiation monitoring instrumentation ensures i

' thats (1) the radiation levels are continually measured in the areas served by the individual channels, and (2) the alarm or automatic action is initiated when the radiation level trip setpoint is exceeded. Specified surveillance intervals and surveillance and maintenance outage times have been determined in accordance with GENE-770-06-1-A, " Bases for Changes to surveillance Test ;

Intervals and Allowed out-of-service Times for selected Instrumentation :

Technical specifications", December 1992. When a channel is placed in an inoperable status solely for performance of required surveillances, entry into ,

LCO and required ACTIONS may be delayed, provided the associated function t

maintains initiation capability. !

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1A SALLE - UNIT 2 3 3/4 3-4 Amendment No. 90 .

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ATTACHMENT B PROPOSED AMENDMENTS TO THE LICENSETTECHNICAL SPECIFICATIONS INSERT B An auxiliary relay contact of Channel A of the RCIC Reactor Vessel Water Level-High, Level 8 instrumentation channelis used as an input to trip Channel C of the Feedwater/ Main Turbine Trip System Actuation Instrumentation. Therefore, the Limiting Condition for Operation and Surveillance Requirements of both TS 3/4.3.5 and 3/4.3.8 are applicable to the RCIC level 8 channel A instrumentation channel.

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INSTRUMENTATION !

1

' . i g ,. BASEE l

a 3/4.3.7.11 EXPI.OSTVE CAS MONITORING TNo n nunirv1aTION l This instrumentation provides for monitoring (and contro13ing) the {

j concentrations system.

of potentially explosive gas mixtures in the waste gas holdup ;

j 3/4.3.7.12 LOOSE-PART DETECTION SYSTEM i

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The OPERABILITY of the loose-part detection sys' tem ensures that !

eufficient capability is available to detect loose metallic parts in the j primary system and avoid or mitigate damage to primary system components. .The j allowable out-of-service times and surveillance requirements are consistent -

with the raccounendations of Regulatory Gelde 1.133, " Loose-Part Detection Program for the Primary System of Light-Water-cooled Reactors."

-4 3/4.3.5 FernWATER/MATN TURRYNE TRTP SYs11n ACTUATION TWarnITnzn1ATION The feedwater/ main turbine trip system actuation instrumentation is provided.to initiate the feedwater systems / main turbine trip system in the event of reactor vessel water level equal to or greater than the level 5 i setpoint associated with a feedwater controller failure, to prevent overfilling the reactor vessel which may result in high pressure liquid discharge through the safety / relief valve discharge lines. Specified surveillance intervals and surveillance and maintenance outage tiJaes have been l

determined in accordance with GENE-770-06-1-A, " Bases for Changes to -

Surveillance Test Intervals and Allowed out-of-service Times for selected Instrumentation Technical specifications", December 1992. When a channel is ,

placed in an inoperable status solely for performance of required surveillances, entry into Leo and required ACTIONS may be delayed, provided '

the associated function maintains Feedwater system / Main Turbine Trip system !

actuation capability. -

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e LA SALLE - UNIT 2 3 3/4-3-6 Amendment No. 90

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, i y 7 ATTACHMENT B _

PROPOSED AMENDMENTS TO THE

L LICENSEITECHNICAL SPECIFICATIONS l 1

INSERT C !

The four instr'ument channels are arranged to make a two out'of three trip logic. In

{ : order to eliminate the loss of the reactor vessel water level eight trip due to the loss of '

, either variable leg instrument line for narrow range level instrurnentation, trip channel C of the level 8 trip logic contains two reactor vessel water level 8 sensor trip relay 1 contacts. Therefore, trip channel C contains two channels, providing the redundancy j l needed to prevent a failure to trip of the feedwater pumps / main turbine due to an

instrument line failure. One of the four channels (one of the two channels in trip '

. channel C) is from the Channel A, RCIC reactor vessel water level 8 trip relay, which ,

..is associated wi'ln TS 3.3.5. Reactor Core Isolation Cooling System Actuation

Instrumentation. .

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Actions b.1 and b.2 are modified by a Note that states that an inoperable channel need not be placed in the tripped condition where this would cause the Trip Function to occur. This note acknowledges that an orderly shutdown per Action c is preferred to the transient that will occur if the trip were actuated.

Action b.1 assures that whatever combination of channels are inoperable, that automatic trip capability either exists or is restored within two hours, which is sufficient for the operator to take corrective action and takes into account the likelihood of an event requiring actuation of this Trip Function. This will require a minimum of two

channels Operable or one channel Operable with one channel in the tripped condition in order to satisfy Action b.1. If Action b.1 is satisfied, then Action b.2 is entered. If ,

Action b.1 is not satisfied, then Action c must be entered.

- Action b.2 assures that each inoperable channelis placed in the tripped condition

" within 7 days. If each inoperable channelis in the tripped condition or declared +

2 Operable within 7 days, then continued unit operation is allowed, due to the remaining '

, redundancy for single instrument failure. If one or more channels are inoperable, and cannot be placed in the tripped condition or declared Operable within 7 days, then !

Action c must be entered.

An auxiliary relay contact of Channel A of the RCIC Reactor Vessel Water Level-

- High, Level 8 instrumentation channelis used as an input to trip Channel C of the i Feedwater/ Main Turbine Trip System Actuation Instrumentation. Therefore, the c Limiting Condition for Operation and Surveillance Requirements of both TS 3/4.3.5 i and 3/4.3.8 are applicable to the RCIC level 8 channel A instrumentation channel.

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ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION Summary of the Proposed Technical Specification chanaes:

This proposed license amendment will change Technical Specification (TS) 3/4.3.8, Feedwater/ Main Turbine Trip System Actuation Instrumentation, due to a design change to resolve an instrument line redundancy issue concerning the Reactor Vessel Wabr Level-High, Level 8, Trip Function. The actuation logic currently consists of three reactor water level instruments with auxiliary relay contacts arranged in a two out of three trip logic. Therefore, when high reactor water level is sensed by any two of the three level instruments, an actuation signal is generated to trip the Feedwater Pumps and the Main Turbine.

There are only two narrow range variable water legs for the narrow range reactor water levelinstrumentation. As a result, two of the Feedwater/ Main Turbine reactor high water level instruments are on one narrow range variable water leg, the remaining instrument is on the other narrow range variable water leg.

A design change is being installed during the current outages for LaSalle County i Station (LaSalle) Units 1 and 2 that adds an auxiliary contact from a RCIC Reactor Vessel Water Level-High, Level 8, channel A instrument to channel C of the Feedwater/ Main Turbine logic. This will prevent a failure to trip the Feedwater Pumps ,

and Main Turbine on high level due to the loss of one of the two narrow range level )

variable water leg instrument lines. The Feedwater/ Main Turbine logic will remain a two out of three logic.

As 6 msult of the design changes, the number of ,'astruments required to be Operable for thit trip function is being increased from ' to 4. As a result, the minimum operable l channels per trip system is proposed to be changed from 3 to 4 in TS Table 3.3.8-1, and the TS 3.3.8 Feedwater/ Main Turbine Trip System Actuation instrumentation Limiting Condition for Operation Action statements are proposed to be changed due to the logic change while maintaining consistency with the current action requirements.

Commonwealth Edison has evaluated the proposed Tec'.nical Specification Amendment and determined that it does not represent a significant hazards consideration. Based on the criteria for defining a significant hazards consideration established in 10 CFR 50.92. operation of LaSalle County Station Units 1 and 2 in accordance with the proposed amendment will not:

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i ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION

1) Involve a significant increase in the probability or consequences of an accident previously evaluated because:

The proposed Technical Specification (TS) change will resolve the common instrument line failure (break) from preventing reactor high water level trip of Feedwater Pumps and Main Turbine. It will not change the probability of occurrence of any accidents, because this instrumentation is not an accident initiator. This instrumentation resolves a potential concern regarding the results of an instrument line break in conjunction with a Feedwater Controller Failure Maximum Demand, which has been postulated and analyzed separately, but are not required to be analyzed in combination, as is described in Chapter 15 of the LaSalle UFSAR. There will not be >

any increase in probability of feedwater transient (postulated feedwater controller failure with assumed simultaneous failure of one high level trip channel of Feedwater/ Main Turbine Trip Actuation Instrumentation), nor an instrument line break.

The design change associateo with this TS change will prevent the failure of the level 8 trip of Feedwater Pumps and Main Turbine due to loss of common variable water leg of level instrument channels "B" and C". Thus there is a slight increase the ,

reliability of the high level trip by assuring that a single instrument failure, including a failure of a sensing line, will not prevent a level 8 trip. The Feedwater/ Main Turbine Trip on Reactor Vessel Weter Level-High, Level 8, mitigates the conseque 'ces of the transient, Feedwater Contr<.,ller Failure Maximum Demand, due to the main turbine trip with subsequent Turbine Stop Valve closure scram and Reactor Recirculation Pump Trip. This limits the neutron flux peak and fuel thermal transients so that no fuel damage occurs. MCPR remains at or above the operating limit and peak centerline fuel temperature increase is small. The consequences of an accident will not increase, because the redundancy of the instrumentation portion of the Trip Function is somewhat increased. 1 1

TS 3.3.8 Limiting Condition for Operation (LCO) Actions b and c are proposed to be l changed to be similar to the LCO for TS 3.3.1, Reactor Protection System Action b.1 to assure trip capability, while being consistent with the allowed outage times of current TS 3.3.8. Also, the proposed action statements and allowed outage times are consistent with LCO 3.3.2.2, "Feedwater and Main Tu bine High Water Level Trip Instrumentation", of NUREG 1433, Revision 1, Standard Technical Specifications, General Electric Plants, BWR4, dated April 1995. The limit on continued plant operation of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months in current Action c.1, is overly restrictive, since with one inoperable channel tripped and one Operable channel, the Trip Function is restored to the same status as current Action b.1 (one more instrument failure will cause a failure to actuate on high reactor water level). Therefore, although the proposed Actions are C-2

ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION iricreasing the allowed outage time for the case with only one remaining Operable ,

channel, from 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months to 7 days, the level of protection for automatic trip capability is j maintained except for a 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months period during which trip capability may not exist. In 1 addition, like current Action b.1, the proposed Actions assure that the longest time i that automatic trip capability failure due to another instrument failure will exist is 7 l days. Therefore, the potential for failure of the Feedwater/ Main Turbine trip on reactor l

. vessel high water level may be slightly increased, but is not significant considering the I non-safety-related Feedwater Pump and Main Turbine trips are not and are not !

required to be single-failure proof.

Based on the above, the proposed amendment will not increase the probability or consequences of any accident previously evaluated.

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

The Feedwater/ Main Turbine trip is a non-safety function in the non-safety-related feedwater system. The high water level trip is an equipment protective action preventing main steam carry over in the main steam from damaging main turbine and preventing high pressure liquid discharge through the safety relief valve discharge lines in case of a feedwater transient due to a controller failure to maximum demand.

The trip system is not designed to any applicable standards or regulatory guides or (

10CFR50 Appendix A General Design Criteria per UFSAR Table 7.1-2. The trio system is not designed nor required to meet the single failure criteria. This is a rdn- l safety /non-divisional trip actuation required in Operating Condition 1, Run Mode, such !

that high integrity of the trip is maintained. The feedwater system is not required to ;

mitigate the consequences of accidents. ;

1 The design change associated with this TS change will increase the reliability of the trip logic. This is accomplished by assuring that a failure of a sensing line will not i prevent or cause a level 8 trip. The failure of Feedwater/ Main Turbine channel "C" trip channel will not have any impact on the RCIC system nor Feedwater/ Main Turbine i channels "A" & *B", because the added signal is isolated by a safety-related relay. The 2 out of 3 logic for the trip is maintained.

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I ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION in addition, the changes to the action statements of the specification do not allow a condition that could cause the actuation instrumentation to fail in a different manner.

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Based on the above, the proposed change will not create the possibility of a new or l different kind from any accident or transient previously evaluated. 1

3) Involve a significant reduction in the margin of safety because:

The proposed TS change will not prevent tripping of Feedwater/ Main Turbine or cause false trips. The existing 2 out of 3 logic trip is maintained and does not affect existing failure modes or introduce new failure modes. This change will prevent failure of level i 8 trip of Feedwater Pumps and Main Turbine upon loss of common variable water leg I for Reactor Vessel Water Level-High, Level 8, instrument channels "B" & C" and will slightly increase reliability of the trip logic. Failure of the non-safety-related trip logic ;

will not impact any safety-related system, structure, or component.

The changes to the TS LCO Action statements is consistent with the existing actions, while minimizing the time that automatic trip capability is not maintained. The change from 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months allowed operation with one channel Operable and only one channel tripped to 7 days is consistent with the current allowed outage time for only one channelinoperable and not tripped, so any change to the margin of safety provided by the current action requirements is minor.

Based on the above, the proposed TS change does not involve a significant reduction in the margin of safety.

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ATTACHMENT C SIGNIFICANT HAZARDS CONSIDERATION

. a Guidance has been provided in " Final Procedures and Standards on No Significant Hazards Considerations," Final Rule, 51 FR 7744, for the application of standards to _;

license change requests for determination of the existence of significant hazards j considerations. This document provides examples of amendments which are and are j not considered likely to involve significant hazards considerations. These proposed j amendments most closely fit the example of a change which either result in some :

increase to the probability or consequences of previously analyzed accident or may in some way reduce a safety margin, but where the results of the change are clearly j within the acceptable criteria with respect to the system or component specified in i Standard Review Pl:.n. i This proposed amiendment does not involve a significant relaxation of the criteria used to estaolish safety limits, a significant relaxation of the bates for the limiting safe) system settings or o significant relaxation of the bases for the limiting conditions for ;

operations. Therefore, based on the guidance provided in the Federal Register and i the criteria established in 10 CFR 50.92(c), the proposed change does not constitute a significant hazards consideration.

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.; , * - l ATTACHMENT D ENVIRONMENTAL ASSESSMENT STATEMENT APPLICABILITY REVIEW Commonwealth Edison has evaluated the proposed amendment against the criteria for identification of licensing and regulatory actions requiring environmental assessment in accordance with 10 CFR Part 51.21. It has been determined that the proposed changes meet the criteria for categorical exclusion as provided for under 10 CFR Part 51.22(c)(9). This conclusion has been determined because the changes requested do not pose significant hazards considerations or do not involve a significant increase in the amounts, and no significant changes in the types of any effluents that may be released off-site. Additionally, this request does not involve a significant increase in individual or cumulative occupational radiation exposure.

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ML20137W513

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