Text

Proposed Tech Spec Change 99-03, Main Control Room Emergency Ventilation Sys Versus Radiation Monitors. Changes Add LCOs 3.3.3.1 & 3.7.7 to Address Inoperability of Radiation Monitoring CREVS & NUREG-1431 Recommendations
	ML20206E139
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Site:	Sequoyah
Issue date:	04/29/1999
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Li.

I l'

j ENCLOSURE 2 TENNESSEE VALLEY AUTHORITY SEQUOYAH PLANT (SQN)

UNITS 1 AND 2 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE 99-03 MARKED PAGES I.

AFFECTED PAGE LIST 1

Unit 1 l

3/4 3-40 3/4 3-41 3/4 7-17 B 3/4 3-2 B 3/4 7-4 Unit 2 3/4 3-41 3/4 3-42 3/4 7-17 B 3/4 3-2 B 3/4 7-4 II.

MARKED PAGES See attached.

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TABLE 3.3-6 (Continued) i ACTION STATEMENTS ACTION 26 -

With the number of OPERABLE channels less than required l

by the Minimum Channels OPERABLE requirement, perform area j

surveys of the monitored area with portable monitoring l

instrumentation at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

l I

ACTION 27 -

With the number ofOPERABLE channels less than required I

by the Minimum Channels OPERABLE requirernent, comply with l

q the ACTION requirements of Specification 3.4.6.1.

l j

lR16

)

ACTION 28 -

With the number of OPERABLE channels less than required l

j by the Minimum Channels OPERABLE requirement, comply with the ACTION requirer o. of Specification 3.9.9 (MODE 6) and IR172 3.3.2.1 (MODES 1,2

_ a 4).

l l

ACTION 29 a

With one channelinoperable, place the associated control room emergency ventilation system (CREVS) train in recirculation mode of operation within 7 Day or be in at Icast HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD INSERTS SHUTDOWN within the followine 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

w_

J b

With the-two channels inoperable number cf cper b!::hann6 !:= N required by

'h: P'%um Chann& OPE ABLE ::qu:::m:nt, within I hour initiate and l

maintain operation of the-o!!e CREVS cc-tre! recm :mer;;:n;y.:n!!! :!cn :y :::r IR16

)

train in the recirculation mode of operation and enter the required Actions for one l

CREVS train made inoperable by inoperable CREVS actuation instrumentation.

)

Or place both trains in the recirculation mode of operation within one hour.

If the completion time of Action 29b cannot be met in MODES 1. 2. 3. and 4. he in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the followine 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

If the completion time of Action 29b cannot be met during the movement ofirradiated fuel assemblies, suspend core alterations and susDend movement ofirradiated fuel assemblies.

If the completion time of Action 29b cannot be met in MODES 5 and 6. initiate action to restore one CREVS train.

I

(

IRll6 l

l SEQUOYAH - UNIT 1 3/4 3-41 Amendment No. 12,112,168

PLANT SYSTEMS 3/4.7.7 CONTROL ROOM EMERGENCY VENTILATION LIMITING CONDITION FOR OPERATION 3.7.7 Two independent control room emergency ventilation systems (CREVS) shall be OPERABLE.

I IRl91 APPLICABILITY: ALL MODES and During Movement ofIrradiated Fuel Assemblies j

\\

ACTION:

MODES 1,2,3 and 4 INSERTS a.

With one CREVS inoperable, restore the inoperable system to OPERABLE statt wit n 7 day r be in ai least I

lR191 HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD S11UTDOWN within ti fol wing 3 ours.

l b.

With both CREVS inoperable due to actions taken as a result of a tornado I

warning, restore at least one train to operable status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months or I

l be in a least liOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD Sil DO I

within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

I l

L With both CREVS inoperable for other than Action b., be in at least OT ST DBY within the neit 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

MODES 5,6, and During Movement ofIrradiated Fuel Assemblies lR191 With one CREVS inoperable, restore the inoperable system to OPERABL status within 7 days or initiate and I

a.

i maintain operation of the oDerable CREVS =-tr;! reem =rg=:y =.' ::en cy := in the recirculatio l

a mode I

.9.r :

llNSERT l'

suspend core alterations and suSDend movement ofirradiated fuei assembiies.

b.

With both CREVS inoperable, suspend all operations involving CORE ALTERATIONS and er suspend "

lR191 movement ofirradiated fuel assemblies cd v: r=" ::y d=g=.

I c.

The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE REQUIREMENTS 4.7.7 Each CREVS shall be demonstrated OPERABLE:

R191 a.

At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by verifying that the control room air temperature is less than or equal to 104'F.

b.

At least once per 31 days on a STAGGERED TEST BASIS by initiating, from the control room, flow through the IIEPA filters and charcoal adsorbers and verifying

- that the system operates for at least 15 minutes.

c.

At least once per 18 months or (1) after any structural maintenance on the llEPA filter or charcoal adsorber housings, or (2) following painting, fire or chemical release in any ventilation zone communicating with the system by:

October 17,1994 SEQUOYAll-UNIT 1 3/4717 Amendment Nos. 12,164,187

I r.

f Insert to Bases Section:

l

. 3 / 4 ', 3. 3. '1 RADIATION MONITORING INSTRUMENTATION i

Relative to the control room instrumentation isolation function, one set of process radiation monitors acts to automatically initiate control room

~ isolation. 'The actuation instrumentation consists of redundant radiation monitors. A high radiation signal from the-detector will initiate its associated train of the Control Room Emergency Ventilation System (CREVS).

The CREVS is also automatically actuated by a safety injection (SI) signal from either unit.

The SI function is discussed in LCO 3.3.2,

" Engineered Safety Feature Actuation System (ESEAS) Instrumentation." In addition, the i

control room operator can manually initiate CREVS.

f1.

INSTRUMENTATION l

BASES-l l.

[

The measurement of response time at the specified frequencies provides assurance that the protective and

. ESF action function associated with each channel is completed within the time limit assumed in the accident analyses.'

l No credit was taken in the analyses for those channels with response times indicated as not applicable in the updated final safety analysis report.

lRl94 l

l Response time may be demonstrated by any series of sequential, overlapping or total channel test measurements provided that such tests demonstrate the total channel response time as defined. Sensor response time verification may be demonstrated by either 1)in place, onsite or offsite test measurements or 2) utilizing replacement I

sensors with certified response times.

1b

. Action 15 of Table 3.3-1, Reactor Trip System Instrumentation, allows the breaker to be bypassed for up to l

4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months for the purpose of performing maintenance. The 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months is based on a Westinghouse analysis performed in

(

.-WCAP-10271, Supplement 1, which determines bypass breaker availability.

R$8 The placing of a channel in the trip condition provides the safety function of the channel. If the channel is BR-9 tripped for testing and no other condition would have indicated inoperability, the channel should not be declared

' inoperable.

The Auxiliary Feedwater (AFW) Suction Pressure-Low function must be OPERABLE in MODES 1,2, and 3 to ensure a safety grade supply of water for the AFW System to maintain the steam generators as the heat _ sink for R242 the reactor, nis function does not have to be OPERABLE in MODES $ and 6 because heat being generated in the l-

' reactor is removed via the Residual Heat Removal (RHR) System and does not require the steam generators as a heat L

sink. In MODE 4, AFW automatic suction transfer does not need to be OPERABLE because RHR will already be in operation, or sufficient time is available to place RHR in operation to remove decay heat.

' 3/4.3.3 MONITORING INSTRUMENTATION -

3/4.3.3.1 RADIATION MONITORING INSTRUMENTATION ne OPERABILITY of the radiation monitoring channels 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 the

~ radiation level trip setpoint is exceeded.

llNSERT L 3/4.3.3.2 MOVABLE INCORE DETECTORS The OPERABILITY of the movable incore detectors with the specified minimum complement of equipment ensures that the measurements obtained from use of this system accurately represent the spatial neutron flux distribution of the reactor core. The OPERABILITY of this system is demonstrated by irradiating each detector used and determining the acceptability ofits voltage curve.

For the purpose of measuring Fn(X,Y,Z) or Fan (X,Y) a full incore flux map is used. Quarter-core flux maps, lR227

' as defimed in WCAP-8648, June 1976, may be used in recalibration of the excore neutron flux detection system, and full incore flux maps or symmetric incore thimbles may be used for monitoring the QUADRANT POWER TILT RATIO when one Power Range Channel is inoperable.

November 19,1998 SEQUOYAH - UNIT 1 '

B3/43-2 Amendment No. 54,190,223,238 2

r Insert to Bases Section:

f-

.3/4'.7.7 CONTROL ROOM EMERGENCY VENTILATION SYSTEM (CREVS)

LCOs are based on two independent and redundant CREVS trains being required to be OPERABLE to ensure that at least one is available assuming a single failure disables the other train. Total system failure could result in exceeding a dose of 5 rem to the control room operator in the event of a large radioactive release.

l The CREVS is considered OPERABLE when the individual components necessary to limit operator exposure are OPERABLE in both trains. A CREVS train _is OPERABLE when the associated:

I a.

Fan is OPERABLE; b.

HEPA filters and charcoal adsorbers are not excessively restricting flow, and are capable of performing their filtration-functions; and c.

Ductwork, valves, and dampers are OPERABLE, and air circulation can be maintained.

In addition, the control room boundary must be maintained, including the integrity of the walls, floors, ceilings, ductwork, and access doors.

E

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PLANT SYSTEMS r

BASES-i

- 3/4.7.5 ULTIMATE HEAT SINK (UHS)

The limitations on UHS water level and temperature ensure that sufficient cooling capacity is available to _

R83

- either 1) provide normal cooldown of the facility, or 2) to mitigate the effects of accident conditions within acceptable limits.

The limitations on the maxircum temperature are based on _providing a 30 day cooling water supply to safety R12 related equipment without exceeding their design basis temperature and is consistent with the recommendations of Regulatory Guide 1.27, " Ultimate Heat Sink for Nuclear Plants", March 1974.

- The limitations on minimum water level are based on providing sufficient flow to the ERCW serviced heat loads after a postulated event assuming a time-dependent drawdown of reservoir level. Flow to the major transient :

heat loads (CCS and CS heat exchangers) is balanced assuming a reservoir level of elevation 670. The time-R83 independent heat loads (ESF room coolers, etc.) are balanced assuming a reservoir level of elevation 639, lBR 10 3/4.7.6 FLOOD PROTECTION The requirements for flood protection ensures that facility protective actions will be taken and operation will be terminated in the event of flood conditions. A Stage i flood warning is issued when the water in the forebay is predicted to exceed 697 feet Mean Sea Level USGS datum during October i through April 15, or 703 Feet Mean Sea Level USGS datum during April 15 through September 30. A Stage 11 flood warning is issued when the water in the forebay is predicted to exceed 703 feet Mean Sea Level USGS datum. A maximum allowed water level of 703 Mean Sea Level USGS datum provides sufficient margin to ensure waves due to high winds cannot disrupt the flood mode preparation. A Stage 1 or Stage 11 flood warning requires the implementation of procedures which include plant shutdown. Further, in the event of a loss of communications simultaneous with a critical combination flood, headwaters, and/or seismically induced dam failure the plant will be shutdown and flood protection measures implemented.

3/4.7.7 CONTROL ROOM EMERGENCY VENTILATION SYSTEM De OPERABILITY of the control room ventilation system ensures that 1) the ambient air temperature does not exceed the allowable temperature for continuous duty rating for the equipment and instrumentation cooled by this system and 2) the control room will remain habitable for operations personnel during and following all credible accident conditions. The OPERABILITY of this system in conjunction _with control room design provisions is based on limiting the radiation exposure to personnel occupying the control room to 5 rem or less whole body, or its equivalent. This limitation is consistent with the requirements of General Design Criteria 19 of Appendix "A",

10 CFR 50. ANSI N510-1975 will be used as a procedural guide for surveillance testing.

l INSERT l

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. SEQUOYAH - UNIT 1 B3/47-4 Amendment No. 8,79 September 13,1996 l~

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l-TABLE 3.3-6 (Continued)

ACTION STATEMENTS l

ACTION 26 -

With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirement, perform area i

surveys of the monitored area with portable monitoring instrumentation at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

ACTION 27 -

With the number of OPERABLE channels less than required by the. Minimum Channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.4.6.1.

ACTION 28 -

With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.9.9 (MODE 6) and j

3.3.2.1 (MODES 1,2,3, and 4).

R158 i

ACTION 29 a

With one channel inoperable, place the associated control room emergency ventilation system (CREVS) train in recirculation mode of operation within 7 Day or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD INSERTS SHUTDOWN within the followine 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

w_

J b

With htwo channels inoperable mb:: cf ep=b!=h:::

!= S:n eq :md by 6: 3"" nun; Ch:: DOPER ^.BLE nqu!=m:::, within I hour initiate and I

l maintain operation of theo_nLe CREVS x "c' reem =r;;:::y :n !!::!c :yc:r train in the recirculation mode of operation and enter the reautred Actions for one CREVS train made inoperable by inoperable CREVS actuation instrumentation.

.O._I place both trains in the recirculation mode of operation

, ithin one hour.

w If the completion time of Action 29b cannot be met in MODES 1. 2. 3. and 4. be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the followine 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

i If the completion time of Action 29b cannot be met during the movement ofirradiated fuel assemblies, suspend core l

alterations and susDead movement ofirradiated fuel assemblies.

If the completion time of Action 29b cannot be met in MODES 5 and 6. Initiate action to restore one CREVS train.

l R102 SEQUOYAH - UNIT 2 3/4 3-42 Amendment No. 102,158 June 25,1993 i-l

PLANT SYSTEMS 3/4,7.7 CONTROL ROOM EMERGENCY VENTILATION LIMITING CONDITION FOR OPERATION 3.7.7 Two independent control room emergency ventilation systems (CREVS) shall be OPERABLE.

lR179 APPLICABILITY: ALL MODES and Durine Movement ofIrradiated Fuel Assemblies

\\

ACTION:

. MODES 1,2,3 and 4 INSERTS a.

With one CREVS inoperable, restore the inoperable system to OPERABLE stat wit n 7 day r be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within t fol wing 3 iours.

R179 b.

With both CREVS inoperable due to actions taken as a result of a tornado waming, restore at least one train to operable status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months or be in a least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHL DO within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

L With both CREVS inoperable for other than Action b., be in at least OT ST DBY within the neit 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

MODES 5,6, and Durine Movement of Irradiated Fuel Assemblies I

With one CREVS inoperable, restore the inoperable system to OPERABL status within 7 days or initiate and j

a.

maintain operation of the operable CREVS =nt=! :: r :::r;=:y u..!::! cy:::= in the recirculatio a pi79 j

mode gr :

llNSERT l

1 susDend core siterations and suspend movement orirradiated fuei assembiies.

4 b.

With both CREVS inoperable, suspend all operations involving CORE ALTERATIONS and ec suspend "

movement ofirradiated fuel assemblies ::S = rr:" ::y d=ge.

R179 c.

The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE REQUIREMENTS 4.7.7 Each CREVS shall be demonstrated OPERABLE:

l a.

At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by verifying that the control room air temperature is less than or equal to 104*F.

. b.

At least once per 31 days on a STAGGERED TEST BASIS by initiating, from the control room, flow through the HEPA filters and charcoal adsorbers and verifying that the system operates for at least 15 minutes.

c.

At least once per 18 months or (1) after any structural maintenance on the HEPA filter or charcoal adsorber housings, or (2) following painting, fire or chemical release in any ventilation zone communicating with the system by:

October 17,1994 SEQUOYAH - UNIT 2 3/4 7-17 Amendment Nos. 154,179

w-3 u s.

n

,n.,

a s

p.

l Insert to' Bases Section:

3/4.3.3.1 RADIATION MONITORING INSTRUMENTATION Relative to the control room instrumentation isolation function, one set of process radiation monitors acts to automatically initiate control room isolation.

The actuation instrumentation consists of redundant radiation monitors. A high radiation signal from the detector will initiate its associated train of the Control Room Emergency Ventilation System (CREVS).

The CREVS:is also automatically actuated by a safety injection (SI) signal from'either unit.

The SI function is discussed in LCO 3.3.2, " Engineered

. Safety Feature Actuation System (ESFAS) Instrumentation.".In addition, the control room operator can manually initiate CREVS.

l l

f I

r i

l L

y INSTRUMENTATION BASES REACTOR TRIP SYSTEM AND ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION (Continued)

The measurement of response time at the specified frequencies provides assurance that the protective and the engineered safety feature actuation associated with each channel is completed within the time limit assumed in the accident analyses. No credit was taken in the analyses for those channels with response times indicated as not applicable in the updated final safety analysis report.

R182 Response time may be demonstrated by any series of sequential, overlapping or total channel test measurements provided that such tests demonstrate the total channel response time as defined. Sensor response time verification may be demonstrated by either 1) in place, onsite or offsite test measurements or 2) utilizing replacement sensors with certified response times.'

Action 15 of Table 3.3-1, Reactor Trip System Instrumentation, allows the breaker to be bypassed for up to 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months for the purpose of performing maintenance. The 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months is based on a Westinghouse analysis performed in R46 WCAP-10271, Supplement 1, which determines bypass breaker availability.

The placing of a channel in the trip condition provides the safety function of the channel. If the channel is tripped for testing and no other condition would have indicated inoperability, the channel should not be declared BR-10 inoperabic.

The Auxiliary Feedwater (AFW) Suction Pressure-Low function must be OPERABLE in MODES 1,2, and 3 to ensure a safety grade supply of water for the AFW System to maintain the steam generators as the heat sink for the reactor. This function does not have to be OPERABLE in MODES 5 and 6 because heat being generated in the R228 l

reactor is removed via the Residual Heat Removal (RHR) System and does not require the steam generators as a heat 1

sink. In MODE 4, AFW automatic suction transfer does not need to be OPERABLE because RHR will already be in operation, or sufficient time is available to place RHR in operation to remove decay heat.

3/4.3.3 MONITORING INSTRUMENTATION

' 3/4.3.3.1 RADIATION MONITORING INSTRUMENTATION The OPERABILITY of the radiation monitoring channels 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 the i

n diation level trip setpoint is exceeded.

l INSERT 1

3/4.3.3.2 MOVABLE INCORE DETECTORS l;

The OPERABILITY of the movable incore detectors with the specified minimum complement of equipment i-ensures that the measurements obtained from use of this system accurately represent the spatial neutron flux i'

distribution of the reactor core. The OPERABILITY of this system is demonstrated by irradiating each detector used and determining the acceptability of its voltage curve.

l.

For the purpose of measuring Fn(X,Y,Z) or Fan (X,Y) a full incore flux map is used. Quarter-core flux maps, lR214 as defined in WCAP-8648, June 1976, may be used in recalibration of the excore neutron flux detection system, and full incore flux maps or symmetric incore thimbles may be used for monitoring the QUADRANT POWER TILT

' RATIO when one Power Range Channel is inoperable.

November 19,1998 SEQUOYAH - UNIT 2 B 3/4 3-2 Amendment Nos. 46,72,182, l

214,228 L

pc.,_...

, s. a _2.

4__.

. 2.._' _

l b

i Insert to Bases Section:

3/4'.7.7 CONTROL ROOM EMERGENCY VENTILATION SYSTEM (CREVS)

LCOs are based on two independent and redundant CREVS trains being required to be OPERABLE to ensure that at least one is available assuming a

- single failure disables the other train.

Total system failure could. result in exceeding a dose of 5 rem to the control room operator in the event of a large radioactive release.

The CREVS is considered OPERABLE when the individual components necessary to limit operator exposure are OPERABLE in both trains. A CREVS train is OPERABLE when the associated:

a.

Fan is OPERABLE; I

-b.

HEPA filters and charcoal adsorbers are not excessively i

restricting flow, and are capable'of performing their filtration functions; and c.

' Ductwork, valves, and dampers are OPERABLE, and air circulation j

can be maintained.

4 In addition, the control room boundary must be maintained, including the integrity of the walls, floors, ceilings, ductwork, and access doors.

p l

L

' PLANT SYSTEMS

. BASES 3/4.7.5 ULTIMATE HEAT SINK' The limitations on the ultimate heat sink water level and temperature ensure that sufficient cooling capacity R70 is available to either 1) provide normal cooldown of the facility, or 2) to mitigate the effects of accident conditions within acceptable limits.

The limitation on maximum temperature is based on providing a 30 day cooling water supply to safety

. related equipment without exceeding their design basis temperature and is consistent with the recommendations of Regulatory Guide 1.27, " Ultimate Heat Sink for Nuclear Plants", March 1974.

The limitations on minimum water level are based on providing sufficient flow to the ERCW serviced heat loads after a postulated event assuming a time dependent drawdown of reservoir level. Flow to the major transient heat loads (CCS and CS heat exchangers) is balanced assuming a reservoir level of el. 670. The time independent R70 heat loads (ESF room coolers, etc.) are balanced assuming a reservoir level of el. 639.

l BR-il 3/4.7.6 FLOOD PROTECTION The requirements for flood protection ensures that facility protective actions will be taken and operation will be terminated in the event of flood conditions. A Stage i flood warning is issued when the water in the forebay is predicted to exceed 697 feet Mean Sea Level USGS datum during October i through April 15, or 703 Feet Mean Sea Level USGS datum during April l5 through September 30. A Stage Il flood warning is issued when the water in the forebay is predicted to exceed 703 feet Mean Sea Level USGS datum. A maximum allowed water level of 703 Mean Sea Level USGS datum provides sufficient margin to ensure waves due to high winds cannot disrupt the flood mode preparation. A Stage I or Stage Il flood warning requires the implementation of procedures which include plant shutdown. Further, in the event of a loss of communications simultaneous with a critical combination flood, headwaters, and/or seismically induced dam failure the plant will be shutdown and flood protection measures implemented.

3/4.7.7 CONTROL ROOM EMERGENCY VENTILATION SYSTEM The OPERABILITY of the control room ventilation system ensures that 1) the ambient air temperature does not exceed the allowable temperature for continuous duty rating for the equipment and instrumentation cooled by this system and 2) the control room will remain habitable for operations personnel during and following all credible accident conditions. The OPERABILITY of this system in conjunction with control room design provisions is based on limiting the radiation exposure to personnel occupying the control room to 5 rem or less whole body, or its equivalent. This limitation is consistent with the requirements of General Design Criteria 19 of Appendix "A",

10 CFR 50. ' ANSI N510-1975 will be used as a procedural guide for surveillance testing..

[lNSERT --

l September 13,1996 l

SEQUOYAH UNIT 2 B 3/4 7-4 Amendment No. 70

l ENCLOSURE 3 TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT (SQN)

UNITS 1 AND 2 PROPOSED TECHNICAL SPECIFICATION (TS) CHANGE 99-03 REVISED PAGES I.

AFFECTED PAGE LIST s

Unit 1 3/4 3-40 3/4 3-41 3/4 7-17 B 3/4 3-2 B 3/4 3-2a B 3/4 7-4a Unit 2 3/4 3-41 3/4 3-42 l

3/4 7-17 B 3/4 3-2a B 3/4 7-4a 1

II.

REVISED PAGES See attached.

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TABLE 3.3-6 (Continued) l ACTION STATEMENTS J

ACTIONE26 -

With the number of OPERABLE channels less than required by

-the: Minimum Channels OPERABLE requirement,. perform area

~

surveys of the monitored area ~with portable monitoring

' instrumentation at least once per 24. hours.

R16 ACTION 27

'With the-number of OPERABLE channels less than required by,the Minimum Channels: OPERABLE requirement, comply with t m ACTION requirements of Specification 3.4.6.1.

ACTION 28 -

With the number of OPERABLE channels less than required-by;the Minimum' Channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.9.9

-(MODE 6) and 3.3.2.1 (MODES 1,.2, 3, and 4).

R172 j

6

.ACTIONJ29."

a With one channel inoperable, place the associated control. room emergency ventilation system (CREVS) train in. recirculation mode of operation within 7 Days or be.in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 'and in COLD SHUTDOWN.within the following 30" hours.

b With,two channels inoperable, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months initiate'and? maintain operation of one CREVS train in the recirculation mode of-operation and enter the required Actions'for one CREVS train made inoperab?.e by inoperable CREVS actuation instrumentation.

Or place both trains in the recirculation mode of operation'within one hour.

If the completion time of Action'29b cannot be met in MODES 1, 2, 3, and 4, be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD-SHUTDOWN within the.following 30' hours.

?

I If the completion time of Action 29b cannot be met during the movement of irradiated fuel assemblies,

~

suspend core alterations'and suspend movement of irradiated fuel assemblies.-

If the completion time of Action 29b cannot.be met in MODES 5:and 6, initiate action to restore one CREVS train.

L

- SEQUOYAHL- ~ UNIT.. l'

-3/4 3-41 Amendment No. 12, 112, 168,

' PLANT' SYSTEMS

.3/4.7.7 " CONTROL' ROOM EMERGENCY VENTILATION LIMITING' CONDITION FOR OPERATION-3'.7.7 Two independent control room emergency ventilation systems (CREVS) shall R191 be. OPERABLE.

APPLICABILITY: ALL MODES and During Movement of Irradiated Fuel Assemblies-

-ACTION:

MODES 1, 2, 3 and 4

a. With one CREVS_ inoperable,' restore the inoper'able system to OPERABLE status' withinc7' days or be inhat least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

.b.

With both CREVS inoperable due to actions taken as a result of.a tornado R191 warning,. restore.at least one train to operable status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months or be in a'least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

.c._With both CREVS inoperable for other than Action b.,

be in at least HOT STANDBY _within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following

-30 hours.

MODES,5, G, and During Movement of Irradiated Fuel Assemblies

a. With one CREVS inoperable, restore the inoperable system'to OPERABLE status R191

-within 7 days or initiate.and maintain operation of the operable CREVS in the recirculationimode or suspenb_ core alterations and suspend movement of irradiated fuel assemblies.

b.'With both'CREVS inoperable, suspend all operations involving CORE ALTERATIONS' and suspend movement'of irradiated fuel assemblies.

c.JThe. provisions of Specification 3.0.4 ar3 not applicable.

SURVEILLANCE REQUIREMENTS i

4.7.7 Each CREVS shall-be; demonstrated OPERABLE:

gigi a.

At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by verifying that the control room air

. temperature is less than or " equal' to 104*F.

'b.

Atlleast once per 31 days on:a STAGGERED TEST' BASIS by initiating, from

- the ' control : room, flow through the ' HEPA filters and charcoal adsorbers and verifVjng that'the. system operates for'at least 15 minutes.

i c.

-At'least once'per 18 months.or (1).after.any structural maintenance on the HEPA' filter'or charcoal adsorber housings, or (2).following painting,

'firelor chemical-release in any ventilation zone communicating with.the system by:

SEQUOYAH -' UNIT l-3/4 17 Amendment Nos. 12, 164,'187, l <.

g L

7 H

i INSTRUMENTATION-BASES The measurement of response time at the specified frequencies provides assurance that the protective and ESF action function associated with each channel is completed within the time limit assumed in the accident analyses. No credit-was taken in the analyses for those channels with response times indicated as.not applicable in the updated final safety analysis report.

lR194

' Response time may be. demonstrated by any series of sequential, overlapping Lor total channel test measurements provided that such tests demonstrate the total channel response time as defined.

Sensor response time verification may be demonstrated by'either 1) in place, onsite or offsite test measurements or 2) utilizing replacement: sensors with certified response times.

Action 15 of Table;3.3-1, Reactor Trip System Instrumentation, allows the breaker to be bypassed'for up to 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months for the purpose of performing maintenance. The 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months is based on a Westinghouse analysis performed in WCAP-R58 10271, Supplement 1, which~ determines bypass breaker availability.

The placing of a channel in the trip condition provides'the safety function of the channel.

If the channel is tripped for testing and no other condition would have indicated inoperability, the channel should not be. declared BR-9 inoperable.

The Auxiliary Feedwater (AFW) Suction Pressure-Low function must be OPERABLE in MODES 1, 2, and 3 to ensure a safety grade supply of water for'the AFW System.to maintain the steam generators as-the heat sink for the reactor.

This function does not have to be OPERABLE-in MODES 5 and 6 because heat being generated in the reactor is removed via the Residual Heat Removal (RHR) System and.does not require the steam generators as a heat sink.

In MODE 4, AFW automatic suction transfer does-not need to be. OPERABLE because RHR will already

'be in' operation, or sufficient time is available to place RHR in operation to R242 remove decay heat.

3/4.3.3 MONITORING INSTRUMENTATION i

3 / 4.~ 3. 3.1 RADIATION MONITORING INSTRUMENTATION The OPERABILITY of the radiation monitoring channels 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 the radiation

. level trip setpoint is exceeded.

Relative to the control-room instrumentation isolation function, one set of process radiation monitors acts to automatically initiate control room isolation. The actuation instrumentation consists of redundant radiation monitors. A high radiation signal from the detector will initiate its

~

associated train of the Control Room Emergency Ventilation System (CREVS).

The CREVS is-also automatically actuated by a safety injection (SI) signal from either unit.

The SI function.is discussed in: 170 3.3.2,

" Engineered Safety Feature-ActuaLion System (ESFAS) Instrumentation." In addition, the control room operator can manually initiate CREVS.

SEQUOYAH'-LUNIT 1 B 3/4 3-2 Amendment No. 54, 190, 223, 238, e

R

+:

j l

i

'I'STRUMENTATION

)

N BASES 3/4.3.3.2 MOVABLE INCORE DETECTORS The1 OPERABILITY of the movable incore detectors with the specified minimum complement:of. equipment ensures that the measurements obtained from use.of this system accurately represent the spatial neutron flux distribution of the reactor core. The OPERABILITY of this system is demonstrated by irradiating each detector used and determining the acceptability of its voltage curve.

I

' For the purpose of measuring Fo(X,Y, Z) or Fan (X, Y) a full'incore flux map l R227 is used. Quarter-core flux maps, as defined in WCAP-8648, June 1976, may be used

)

in recalibration of the excore neutron flux detection system, and full incore flux maps or symmetric incore thimbles may be used for monitoring the QUADRANT POWER TILT RATIO wnen one Power Range Channel is inoperable.

j j

l

.SEQUOYAH'- UNIT l-B 3/4 3-2a Amendment No. 223,

PLANT SYSTEMS.

BASES 3/4.7.7 CONTROL' ROOM EMERGENCY VENTILATION SYSTEM (Continued)

LCOs are based on two independent and redundant CREVS trains being

-required to be OPERABLE to ensure that at least one is available assuming a single' failure disables the other train. Total system failure could result in exceeding a dose of S rem to the control room operator in.the event of a large radioactive release.

The CREVS is considered OPERABLE when the individual components necessary to limit operator exposure are OPERABLE in both trains. A CREVS train is OPERABLE when the; associated:

a.

Fan is OPERABLE; b.

HEPA filters and charcoal adsorbers are not excessively restricting flow, and are capable of performing their filtration functions; and c.

Ductwork, valves, and dampers are OPERABLE, and air' circulation can be maintained.

In addition, the control room boundary must be maintained, including the integrity of the walls, floors, ceilings, ductwork, and access doors.

SEQUOYAH - UNIT 1 B 3/4 7-4a Amendment-No.

I

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TABLE 3.3-6 (Continued)

ACTION STATEMENTS ACTION 26 -

With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirement, perform area surveys of the monitored area with portable monitoring instrumentation at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

ACTION 27 -

With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.4.6.1.

ACTION 28 -

With the number of OPERABLE channels less than required by the Minimum Channels OPERABLE requirement, comply l

with the ACTION requirements of Specification 3.9.9 (MODE 6) and 3.3.2 (MODES 1, 2,

3, and 4).

R158 ACTION 29 -

a With one channel inoperable, place the associated control room emergency ventilation system (CREVS) train in recirculation mode of operation within

)

7 Days or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

b With two channels inoperable, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months initiate and maintain operation of one CREVS train 1

in the recirculation inode of operation and enter the required Actions l'or one CREVS train made inoperable by inoperable CREVS actuation instrumentation.

Or place both trains in the recirculation mode of operation within one hour.

If the completion time of Action 29b cannot be met in MODES 1, 2, 3, and 4, be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

If the completion time of Action 29b cannot be met during the movement of irradiated fuel assemblies, suspend core alterations and suspend movement of irradiated fuel assemblies.

If the completion time of Action 29b cannot be met in MODES 5 and 6, initiate action to restore one l-

-CREVS train.

R102 SEQUOYAH - UNIT 2 3/4 3-42 Amendment No. 102, 158, t

2,.

e V.

f PLANT SYSTEMS 3/4.7'7 CONTROL ROOM EMERGENCY VENTILATION

, LIMITING CONDITION FOR OPERATION l-3.7.'7

.Two independent. control room emergency ventilation systems (CREVS) shall R179 be~ OPERABLE.

I l

APPLICABILITY: ALL MODES and During Movement of Irradiated Fuel Assemblies

' ACTION:

. MODES 1, 2,'3-and 4 l

a. With.one CREVS inoperable, restore the inoperable system to OPERABLE status-within 7 days or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN.within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

,b..With both CREVS inoperable due to actions taken as a result of a tornado R179

' warning, restore at least one train to operable status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months or be in a least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within j.

the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

.c.

With both CREVS inoperable for other than Action b.,

be in at least HOT

' STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

MODES'5, 6,.and During Movement of Irradiated Fuel Assemblies

a. With one CREVS inoperable, restore the inoperable system to OPERABLE status R179 l

. within 7 days.or initiate and maintain. operation of the operable CREVS in the recirculation mode or

(

suspend core alterations and suspend movement of irradiated fuel assemblies.

b.LWith both CREVS-inoperable, suspend all operations involving CORE

. ALTERATIONS and suspend movement of irradiated fuel assemblies.

c. The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE REQUIREMENTS 4.7.7 Each CREVS shall b'e demonstrated OPERABLE:

i.

a.

At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by verifying that the control room air R179 j.

temperature is less than or equal to 104*F.

i b '.

At least once per 31 days on'a STAGGERED TEST BASIS by initiating, from I

the control room,' flow'through the HEPA filters and charcoal adsorbers and verifying that the-system operates for at least 15 minutes.

.c.

At least once per 18 months or (1) after any structural maintenance on the~HEPA filter or charcoal adsorber housings, or (2) following

painting, fire or chemical release in any ventilation zone communicating with the system by:

..SEQUOYAH - UNIT 2 3/4 7-17 Amendment Nos. 154, 179, j

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I INSTRUMENTATION LBASES REACTOR TRIP SYSTEM AND ENGINEERED SAFETY FEATURE ACTUATION SYSTEM j

INSTRUMENTATION-(Continued) l The. measurement of response time at the specified frequencies provides L

assurance that the protective and engineered safety feature actuation 1

associated with each channel is completed within the time limit assumed in the L

' accident analyses.

No' credit was taken.in the analyses for those channels with response times indicated as not" applicable in the. updated final safety analysis R182' report.

Response time may be demonstrated by any series of sequential, overlapping or total channel test measurements provided that such tests demonstrate the total channel response time as-defined.

Sensor response time verification may be demonstrated-by either 1) in place, onsite or offsite test:

-measurements or 2) utilizing replacement sensors with certified response times.

Action 15 of Table 3.3-1, Reactor Trip System Instrumentation, allows the

-breaker to be bypassed for up to 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months for the purpose of performing maintenance.

The 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months is based on a Westinghouse analysis performed in R46 WCAP-10271, Supplement 1, which determines bypass breaker availability.

The placing of a channel in the trip condition provides.the safety function of the channel.

If the channel is tripped for testing and no other condition would have indicated inoperability, the channel should not be BR-10 i

declared inoperable.

f The Auxiliary Feedwater (AFW) Suction Pressure-Low function must be OPERABLE in MODES 1,2, and 3 to ensure a safety grade supply of water for the AFW System to maintain the steam generators as the heat sink for the reactor.

This function does not have to be OPERABLE in MODES 5 and 6 because heat being generated in the reactor is removed via the Residual Heat Removal (RHR) System and does not require the steam generators as a heat sink.

In MODE 4, AFW automatic suction transfer does not need to be OPERABLE because RHR will already be in operation, or sufficient time is available to place RHR in R228 operation to remove decay heat.

l 3/4.3.3 MONITORING INSTRUMENTATION 3/4.3.3.1 -RADIATION MONITORING INSTRUMENTATION L

The OPERABILITY of the radiation monitoring channels ensures that 1) the f-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 1

level trip setpoint is exceeded.

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l Relative to the control room instrumentation isolation function, one set of. process radiation monitors acts to automatically initiate control room isolation. The actuation instrumentation consists of redundant radiation l'

monitors. A high radiation signal from the detector will initiate its associated train of the Control Room Emergency Ventilation System (CREVS). The CREVS'is also automatically actuated by a safety injection (SI) signal from either unit.

The SI function is discussed in LCO~3.3.2, " Engineered Safety

~ Feature Actuation System- (ESFAS) Instrumentation." In addition, the control room-operator can manually initiate CREVS.

SEQUOYAH'. UNIT 2 B 3/4 3-2 Amendment No. 46, 72, 182, 214, 228, i

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. INSTRUMENTATION BASES

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i 3/4.3.3.2 MOVABLE INCORE DETECTORS-

.The OPERABILITY of the movable incore detectors with the specified minimum complement of equipment ensures that the measurements obtained from use of this' system-accurately represent the spatial neutron flux distribution of'

. the reactor core. The OPERABILITY of this system is demonstrated by

-irradiating each detector used and determining the acceptability of its voltage curve.

L For the purpose of measuring Fg(X,Y, Z) or Fa(X, Y) a full incore flux map l R214

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1s used. Quarter-core flux maps, as defined in WCAP-8648, June 1976, may be l-used in recalibration of the excore neutron flux detection system, and full l

.incore. flux maps or symmetric incore thimbles may be used for monitoring the

- QUADRANT POWER TILT RATIO when one Power Range Channel is inoperable.

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'SEQUOYAH - UNIT 2 B 3/4 3-2a

. Amendment No. 214,

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-PLANT SYSTEMS BASES 3 / 4.' 7. '7 CONTROL ROOM EMERGENCY VENTILATION SYSTEM (Continued)

LCOs are based on two independent and redundant CREVS trains being

required to be OPERABLE to ensure that at least'one is available assuming a single: failure disables the other train.

Total system failure could result in l

exceeding a dose of:S rem to the control room operator in the event of a large

'i radioactive release.

The CREVS is considered' OPERABLE when the individual components necessary.

to limit operator exposure are OPERABLE in both trains.

A CREVS train is OPERABLE when the associated:

a.

Fan is OPERABLE; b.

HEPA filters and charcoal adsorbers are not excessively restricting flow,.and are capable of performing their filtration functions; and c.

Ductwork,' valves, and dampers are OPERABLE, and air circulation can i-be maintained.

In addition, the'. control room boundary must be maintained, including the

-integrity of the walls, floors, ceilings,. ductwork, and access doors.

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l' SEQUOYAH - UNIT 2.

B 3/4 7-4a Amendment No.

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ML20206E139

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