ML20059A339

Proposed Tech Specs Re Changes to Essential Svc Water Cooling Sys

ML20059A339
Person / Time
Site:	Byron
Issue date:	08/16/1990
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML20059A338	List: ML20059A336 ML20059A339
References
NUDOCS 9008220217
Download: ML20059A339 (17)

Text

_

4 ATTACHMENT B=

i PROPOSED CHANGES TO APPENDIX A.

j L-TECHNICAL SPECIFICATIONS-OF FACILITY OPERATING LICENSES NPF-37 AND NPF-66 l.

l P.evtsed Pages:

3/4 7-12 i,

.3/4 7-12a j

L 3/4 7-13 3/4 7-14 3/4 7-14a 3/4 7-15 B 3/4 7-3 i

B 3/4-7_4 t

I L

l

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f.

i s

I

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/sc1:ID66-20 i

9008220217 900816 PDR ADOCK 05000454 P

PDC-1

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PLANT SYSTEMS 3/4.7.4-ESSENTIAL'SERVIC2 WATER SYSTEM LIMITING CONDITION FOR OPERATION s

L lo.ps 3.7.4 At least two independent Essen S rv t

6 j

APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTION:

l cops loop a.

With only one Essential Servic aterA W OPERABLE, restore at.

-least tuo Essential' Service Wate fisseums.to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANOBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTOOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

SURVEILLANCE REQUIREMENTS 4.7.4 AtleasttwoEssentialServiceWateb shall be demonstrated OPERABLE:

At least once per 31 days by verifying that each valve (manual, a.

power-operated, or automatic) servicing safety-related equipment that is not locked, sealed, or otherwise secured in position is in its correct position.

b.

At least once per 18 months during shutdown, by verifying that:

1)

Each automatic valve servicing safety-related equipment or' isolating the non-nuclear safety-related portion of the system actuates to its correct position on a Safety Injectibn test signal, and 2)

Each Essential Service Water Wpump ' starts automaticaily on a Safety Injection-test signal.

D ce per 31 days, by verifying that eat required to e b Specificati

'.. 6perates for at least--

15 minutes and at least onths by visually inspecting and 1

verif n t ~.ma reakage or degra the fill materials a

cooling tower.

BYRON - UNITS 1 & 2 3/4 7-12

.._.~._

N ANI SYSILMS y

3/4.7.4 ESSENilAL SERVICE WATER SYSTEM-s LIMillNG CONDill0N FOR OPERATION 3.7.4.1 A Unit 2 (Unit 1) Essential Service Water pump shall be available to support Unit 1 (Unit 2) operation.

APPLICABillly:

Unit 2 (Unit 1) in MODES 5 and 6 with Unit 1 (Unit 2).in MODES 1, 2, 3, and 4.

ACTION:

I a.it neither Unit 2 (Unit 1) Essential Service Water pump is available, restore one pump to available status within 7 days or place Unit 1 (Unit 2) in at lee t HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the foll_owing 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

k.Mf Pf6Ntod$. of* 5p oSci.~ 3..A ue. *+ c#ble.

SURVEILLANCE REQUIREMENTS 1

4.7.4.1 A Unit 2 (Unit 1) Essential Service Water pump shall be demonstrated available by manually starting and crosstieing to the Unit 1 (Unit 2) system:

At least once per day by verifying that:

s a.

1)

Bus 241 (141) is energized if the 2A (1A) Essential Service

+

Water pump is the available pump or. Bus 242 (142) is energized if the 2B (IB) Essential Service Water pump is the-available 4

pump, and 2)

The following valves are open or capable of being operated from the Control Room:

I a)

SX001A, SX005, SX016A, SX027A, SX033, SX034 and SX143A if 1

the A pump is the available pump, or I

b)

SX001B, SX005, SX0168, SX0278, and SX143B if the B pump is the available pump.

g b.

Atleastonceper31 days,byrunning'theavailablepumpfor{15 minutes.

BYRON UHliS 1 & 2 3/4 7-12a Amendment-No.

l PLANT SYSTEMS

(

3/4.7.5 ULTIMATE HEAT SINK LIMITING CONDITIONS FOR OPERATION 3.7.5 Two independent ultimate heat sinks (VHS) cooling towers shall be OPERABLE with ts j

A minimum water level in each of the UHS cooling tower basins of a.

873.75 feet Mean Sea Level (MSL) (50%),

b.

With o

' operating fans.0A, 08, OE, and qu red to m

be OPERABLE.

W-t 2 opera +

, 00, OG, and OH 25 EAT IM are required to be OPE Units 1 and 2 operating, 3 fans with r S W from each unit a be OPERABLE Lta+ -1 s),

Two OPERABLE essential service water makeup pumps, M

c.

d. p r--M 'h M,9 @._@_ '?? ^3 40WM DI"

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._ -. less than

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b 2 bT':

_' ' L '_. _ "?Z : ' ' ' '

l 3 status Two OPERASL(, pys coch'n3 4Wu Win lwd SNiMu e.

j f.

The National Weather Service (NWS) does net isrecast the Rock River level to exceed 702.0 feet MSL, j

g.

Rock' River water level greater than 670.6 feet MSL, and l

h.

The National Vaather-Service (NWS) has-not issued a tornado watch that includes the Byron Site Area.

l APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTION:

With a water level of less than 873.75 feet MSL (50%) in either UHS a.

cooling tower basin, restore the water level to 873.75 feet'MSL in each UHS cooling tower basin within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> or be in HOT STAND 8Y with-in the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN wP lin the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />, b.

Wit ontained.in the appl-able e * '.;.un listed above inoperable, res ore 6.. 411+-d f... so OPERABLE status within

'(INSfAT' 2.

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in -t '..a NOT STANDBT;wR.;n '" next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and

,Co'_^ L iuuWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />..

i

• No fans a"e required to cooling tower performance testing; however, the at v ce water pump disc ar e main-

_- + 'new as less than or equal to 98'F.

t BYRON - UNITS 1 & 2 3/4 7-13 Amendment No L.

INSERT 1 b.

A total of 6 fans OPERABLE (high speed mode), each capable of being powered from an OPERABLE emergency power source.

t INSERT 2 1

i I

b.

Hith one or two of the above required fans inoperable:

1.

Hithin one hour and at least.once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> ~, thereafter, verify-4 that:

a)

Both of-the UHS cooling tower. basin temperatures areLless than or equal to 70'F, and b)

Four fans are OPERABLE.

The provisions of-Specification'3.0.4 are not applicable..

J 2.

If one or both of the UHS cooling tower basin temperatures is greater than 70'F, restore 6 fans to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be-in-at least HOT STANDBY within the next,6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD.SHUTDOHN within.

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

3.

If both UHS cooling tower basin-temperatures'are less'than or equal d

to 70'F, but there are not'four fans OPERABLE, restore four fans to i

OPERABLE status within-72 hours or be in at least HOT STANDBY within El the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within-the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />, l

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/sc1:ID66 ;

PLANT SYSTEMS LIMITING CONDITION FOR OPERATION a:---

ACTION (Continued)

With one essential service water makeup pump inoperable,within c.

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> either:

1)

Restore the inoperable essential service water makeup pump to OPERABLE 99WMe, or-sta* os

-2)

Verify that the same train deep well pump is OPERABLE with its UHS cooling tower basin level > 83.

Continue to verify basin level is > 83 every two hours and restore the inoperahise sk+ug essential ~ service water makeup pump to OPERABLE $9R9pSWthin l

l

• 7 days.

(*This can be extended to 14 days for Essential Service Water Makeup pump inspection and extended maintenance A

during the time when at least one unit is in IInds 5 or 6.)

MODE, Otherwise be'in at-least HOT STAN08 ithin the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 3 ours.

m UH5 cooM Withg:' r: :' 3 +tMer bosn +smpese+vre, Studer 4hm BB* F d.

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_ L be in at least HOT STAN08Y within i

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

N66AT N

~

f.

With Rock River water level forecasted by NWS to exceed 702.0 feet MSL:

1)

Within one hour verify that both deep well pumps are OPERABLE with both UHS cooling tower basin levels > 83 and at least once every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> thereafter, verify.both basin levels are > 83.

The provisions of Specification 3.0.4 are not applica51e.

1 2)

With one deep well pump inoperable restore both deep well pumps to OPERABLE status with both basin levels > 8 3 before the Rock River level exceeds-702 feet MSL or within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, whichever A1 cosas first and follow provisions of ACTION f.1).-

3)

Otherwise be in HOT STAN08Y within ths' next 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />s-and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

l g.

With Rock River water level at or below 670.6 feet MSL within one hour verify Rock River level and flow, and:

i t

1)

If Rock River level > 664.'7 feet MSL and flow > 700 cfs verify. Rock River level > 664.7 feet MSL and flow 1 700 cfs every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> there-after.

The provisions of Specification 3.0.4 are-not applicable.

2)

If Rock River level 5, 664.7 feet MSL or flow < 700 cfs, within one hour:

BYRON - UNITS 1 & 2 3/4 7-14 Amendment No

11

~

IMEERT 3

'I i

e.

1)

With one UHS cooling tower basin level switch inoperable l

I a)

Within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> either (1) Restore the level switch to OPERABLE status, i

or l-(2)

Increase the basin level in the affected UHS cooling. tower to 1 82%'and at least once-every two' hours thereafter, verify basin level.is 1 82%.

The provisions of Specification-3.0.4 are not applicable.:

I b)

Otherwise be-in at ~ 1 east HOT STANDBY within' the.

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

2)

With both UHS cooling tower basin-level ~ switches inoperable:

l a)

Within one hour either:

(1) Restore.both level switches to OPERABLE' status, or (2) Restore one level switch to OPERABLE status and follow the provisions of ACTION e.1, or-(3)

Increase both UHS cooling: tower' basin levels to 1 82% e.nd at least oncesevery 2' hours.

thereafter, verify both basin levels are 1 82%.

The.provisionsLof. Specification 3.0.4 are not applicable.-

-t b)

Otherwise be in. at least NOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and at least HOT SHUTDOWN within the->

following 6' hours and at least COLD SHUTDOWN j

l-within'the subsequent 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />..

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I (33502)

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. - -. -. ~. - -. - - - -

_ - - + - + -,

PLANT SYSTEMS

• LIMITING CONDITION FOR OPERATION Z_.._:.__2 ACTION (Continued)

~

a)

Verify that both deep well pumps are OPERABLE with both UHS I

cooling tower basin levels > 8 5 and at least once every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> thereafter, verify Both basin levels are > 8 3.

The provisions of Specification 3.0.4 are not appTicable, b)

With one deep well pump inoperable, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> restore both deep well pumps to OPERABLE status with both basin levels

> 83 and follow provisions of ACTION g.2)a).

c)

Otherwise be in at least HOT STANOBY within the next 6 nours-and at least HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and-at least COLD SHUTDOWN within the subsequent 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

h)

With a tornado watch issued by NWS that includes Byron site area:

1)

Within one hour verify that both deep, well pumps are OPERABLE with both UHS cooling tower basin levels > 8 3 and at least once every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> thereafter, verify botE basin levels > 83.

The provisions of Specification 3.0.4 are not applicable!

2)

With one deep well pump inoperable, within 30 minutes take action to restore both deep well pumps to OPERABLE status with both basin levels > 8 3 and at least once every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> thereafter, verify both basin levels > 8 3.

3)

Otherwise be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and-in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

(,

3 BYRON - UNITS 1 & 2 3/4 7-14a AmendmentNo.[

a UHS caelihg + ewer beth, l

I

+.,nper wra

'is le.55 %an l

PLANT SYSTEMS o.nd (a f ao6 cmr OP6g, A6

( to Sg* fr SURVEILLANCE REQUIREMENTS

!- "-- _2

)

4.7.5 The UHS shall be determined OPERABLE at least once per:

a.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> by verifying the. water level in each UHS cooling tower basin to be greater than or equal to 873.75 feet MSL.

(50%),

b.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> by verifying t.he.cr - W r!....

r'^^

• -- - -- "::t-J

^^

c.

24. hours by verifying that the Rock River water level is within its

limits, d.

31 days by starting from the control room each UHS cooling tower fan that is required to be OPERABLE and not already in peration and operatingeachofthosefanbforatleast15 minute

' h. h Spt.t. cl' lS l

E.

31 days by (In bl*3h Spe42) t 1)

Verifying that the fuel supply for each diesel powered essential service water makeup pump is.at.least 36% of the fuel supply tank volume, 2)

Starting the diesel from ambient conditions on a simulated low i

basin level-test signal and operating the diesel powered pump forg30 minutes, 3)

Verifying that each valve (manual, power operated, or. -

automatic) in the flow path is_ in its correct position, g gg4] _

4)

Startin each deep well pump and operating it for es and ver fying that each valve (manual, power-operated, or auto-matic) in the flow path is in its correct position, f.

Deleted 3

g.

92 days by verifying that a drain sample of diesel fuel'from the fuel storage tank, obtained in accordance with ASTM 04057-1981, is within the acceptable limits specified in Table l'of ASTM-D975-1977 when checked for viscosity, water, and sediment, h.

18 months by subjecting each diesel that powers an' essential service water makeup pump to an inspection in accordance with procedures prepared in conjunction with its manufacturer'.s recommendations for the class of service and by cycling each testable valve-in the flow.

path through at least one complete cycle of' full travel, and 1.

18 months by verifying each deep well pump will provide at least 550 gpm flow rate.

j

}.

I B-mon +hs ley Vi$ue.k gn5F+in3 and yef g4%'a3 no %nermaj b reAko.j t, ek ro.dntion c4 +he fi\\\\ mhids ih 3

or c.o h'ng towet.

BYRON - UNITS 1 & 2 3/4 7-15 Amendment No.

4

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,.....--....+-,---..-,-c-t v-y P

L l-PLANT SYSTEh5 l.

1

)

BASES 3/4.7.1.5 MAIN STEAM LINE ISOLATION VALVES Ths OPERABILITY of the main steam line isolation valves ensures that no i

more than one steam gener".or will blowdown in the event of a steam line i

l-rupture.

This restrict 6 is required to: (1) minimize the positive reactivity i

effects of the Reactor C @ nt System cooldown associated with the blowdown, and (2) limit the pressurt rise within containment in the event the steam line rupture occurs within containment.

The OPERABILITY of the main steam isolation valves within the closure times of the Surveillance Requirements are consistent with the assumptions used in the safety analyses.

r i

3/4.7.2 STEAM GENERATOR PRESSURE / TEMPERATURE LIMITATION l

The limitation on steam generator pressure and temperature ensures that the pressure-induced stresses in the steam generators do not exceed the maximum allowable fracture toughness stress limits.

The: limitations of 70 F and l

200 psig are based on a steam generator RT f 60 F and are sufficient NDT to prevent brittle fracture.

I 3/4.7:3 COMPONENT COOLING WATER SYSTEM l

The OPERABILITY of the Component Cooling Water System ensures that l

sufficient cooling capacity is available for continued operation of safety-related equipment during normal and accident conditions.

The redundant cooling capacity,of this system, assuming-a single failure, is consistent with the assumptions used in the safety analyses.

1 3/4.7.4 ESSENTIAL SERVICE WATER SYSTEl.

The OPERABILITY of the Essential Service Water System ensures that sufficient cooling capacity is available for continued operation of safety-related equipment during normal and accident conditions.

The redundant cooling capacity of this system, assuming a single failure,'is consistent with the sumptions used i n the Sodek7 golj6e.S. '

3/4.7.5 ULTIMATE HEAT SINK g

W se#.T Sh Two cooling towe basinscontainwaterthatisimmediatgavailablefor station cooling.

A volume of 200,000 gallons in each basin 3is - =. ___for-supply to the auxiliary feedwater system.;,;ia ;;;.-.; _... ::.^^^ _ -- -

'- M 7

^

,:=___Mg-9 5: ' W. 35-1;.

• >fewet+er+7

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.----- r u

'Theinventory is vailable for transporting heat released from bM unit following a loss!of-coolant accident and the second unit during an orderly shutdown.

Since this inventory would be exhausted in about 1 day, achievement of the design basis requiremen of cooling capability for.30 days is dependent upon r.edundant makeup systems.

5 (ovhJole.

BYRON - UNITS 1 & 2 B 3/4 7-3

INSERT 4

-The' requirement for a pump on the opposite unit to be available with the unit l

crosstle open or capable of being opened from the main control-board enhances l

the reliability of the Essential Service Water System, j

INSERT 5 The Ultimate Heat Sink'(UHS) consists of two redundant essential service water towers and their associated makeup systems.

The towers and the essential service water pumps are designed such that tower 0A provides suction and cooling for the A trains on Units 1 and 2, and tower OB provides the same for i

the B trains.

The maximum heat rejection-to the UHS is from the safe shutdown of bcth units as a result of one unit undergoing a loss of coolant accident (LOCA), the other unit undergoing a complete loss of off-site power (LOOP),.

and then the UHS sustaining the worst case credible' single active failure which is a loss of two fans due to the failure of a Diesel Generator-to start on the LOOP unit.

I l

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p i

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/sc1:1066-26 i

PLANT SYSTEMS BASES 1-ULTIMATE HEAT SINK (Continued)-

l A redundant makeup system using deep wells as a water source is designed l

to withstand design basis tornado events, river flood events, and design basis A

seismic events combined with low Rock River flow or. level.- The second redundant system is the e:sential service water makeup system that uses the Rock River as a water source.

It is oesigned to withstand all design basis natural phenomena events and combinations of events except for seismic events during i

low Rock River flow rates, design basis tornado events and river flood events.

j Each essential service water makeup pump is powered by a diesel engine with a fuel supply adequate for approximately 3 days of operation.

Achievement of the.

design basis 30-day operation is dependent upon successful implementation of plant procedures to replenish the fuel supply following design basis events.

"h water in the cooling tower basin at an initial temperature less '

r equa

'F, shutdown can be achieved,- for meteorological cond fol-t lowing a des sis tornado,.without operation of the coolf er fans and without the temper of the water discharged from the ntial service water pump exceeding 110'F, th imum acceptable tempe for components and l

systems cooled by the essentia ling water om.

Achievement of the desigr i

function of the UHS during more sev rological conditions, or following a design basis LOCA, requires ope o

cooling tower fans to maintain the discharge temperature 1 an or equal t

• F.

Plant procedures ensure that the fans are stare d controlled by operator on to maintain a dis-charge temperatur oss than 110'F.

With all 4 Unit 1 nated cooling tower fans g, either redundant ultimate heat sink train able of edesignbasesLOCAheatloadwithoutexceedingapumpdis remov e-rature of 98 F.

3/4.7.6 CONTROL ROOM 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.

Operation of the. system L

with the heaters operating for at least'10 continuous hours in a 31-day period is' sufficient to reduce the buildup of moisture on the adsorbers and HEPA filters.

The OPERABILITY of this system in conjunction with control room BYRON - UNITS 1 & 2 B 3/4 7-4 Amendment No.

INSERT 6 With the water inventory of one basin and it's assoc 10ted. major piping and an VHS cooling tower basin temperature less than or equal to 70*F, two cooling tower fans operating in high speed can remove a heat. load up to and including that resulting from a design basis LOCA on one unit, and a t.00P with normal shutdown on the other, without exceeding an Essential Servic0 Hater pump discharge temperature of approximately 98*F.

With the water viventory of both basins and their associated major piping and an VHS cooling tower basin temperature of greater than 70'F, but less than or equal to 88'F, four cooling tower fans operating in high -speed can remove the design basis LXA heat load on one unit and a LOOP with normal shutdown on the other, without exceeding an Essential Service Water pump discharge temperature of approximately 98'F.

The maximum acceptable Essential Service Hater pump discharge temperature of 100*F is based upon the known heat transfer characteristics of the Compo'ient Cooling Hater heat exchanger.

The 98'F value allows 2'F as a conservatism.

Plant procedures ensure that the fans are started and controlled as necessary by operator action to maintain an ESH pump discharge temperature within this 100'F limit.

Monitoring of the basin temperature ensures the assumptions of the accident analysis are maintained.

There are several methods which may be utilizied to verify basin temperatures including the monitoring of an operating ESH pump discharge temperature.

Normal plant operations provide for overflow between both UHS basins with an operating pump taking suction from one basin and discharging to the other basin.

This overflow permits communications between the two basins resulting in the operating pump discharge temperature being representative of the discharge temperature of both basins. Also, this indication is expected to be several degrees higher due to pump heat and is therefore a conservative indication of basin temperi;ure.

In the event plant operations would require a basin to be isolated with no overflow communication and no operating ESH pump taking suction from it, direct basin temperature verification would be performed to meet the surveillance requirement.

Specification 3.7.5b requires a certain number of fans to be OPERABLE (high speed mode).

These fans do not need to be in operation in the high speed mode, just capable of operating in their high speed mode upon receipt of a start signal.

With the basin temperature less than or equal to 70'F, any four fans meet the specification.

With the basin temperature greater than 70'F, 3

any 6 fans meet the specification. An OPERABLE fan must be capable of being powered from an OPERABLE emergency power source. A fan's emergency power source is considered OPERABLE if its unit associated diesel generator is OPERABLE or if the same train diesel generator from the other unit is operable and capable of being crosstled to the fan's unit bus.

For example the OA and OB fans normal emergency power feed is the 1A diesel generator.

If the 1A diesel generator is inoperable, the 2A diesel generator must-be OPERABLE and capable of being crosstled to the Unit 1 bus for fans OA and OB to be considered OPERABLE.

This is conservative given that the unit undergoing the LOCA does not lose it's offsite power, therefore, the LOOP unit's fans can be powered (crosstled) from the LOCA unit's SATs.

Compliance with LCO 3.7.5 is maintained even though multiple ACTION statements are in effect.

For example, with one UHS cooling tower basin inoperable because of level and one of the required fans inoperable, provided the applicable ACTIONS are followed, compliance with the LC0 is maintained.

However, if compliance with the LC0 is not maintained because t,<o VHS cooling tower basin are inoperable or more than two of the required fans are inoperable, then Specification 3.0.3 must be followed.

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ATTACHMENT C EVALUATION OF SIGNIFICANT HAZARDS COMIDERATIONS Commonwealth Edison has evaluated this proposed amendment and determined that it involves no significant hazards consideration. According to 10CFR50.92(c), a proposed amendment to an operating license involves no-significant safety hazards considerations if operation of the facility in accordance with the proposed amendment would not:

1. Involve a significant increase in the probability or consequences of an 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 amendment involves several changes as follows:

1

1. The references to the cooling tower and its associated surveillances have been relocated from Specification 3.7.4 to 3.7.5.

Also Essential Service Hater Systems have been changed to Essential Service Hater loops since the Ultimate Heat Sink (VHS) and Essential Service Hater (ESH) loops comprise the system.

The letter case has been changed to the words status and mode in specification 3.7.5.

Bases Section

'r 3'4.7.4 was revised to include an editorial change and additional justification for the availability of the other units ESH pump and crosstle capability.

2. A statement that the provisions of Specifications 3.0.4 are not applicable has been added to Specification 3.7.4.1-.

3. LC0 3.7.5b was revised to require six fans operable in the high speed mode each capable of being powered from an operable emergency power source.

This change was as a result of the VHS cooling tower performance testtrg.

If +he six fans are not operable, revised Action b requires periodic verification that UHS cooling tower Dasin temperature is less than or equal to 70*F and that there are four I

fans.

If these conditions are not met they must be restored in 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or a unit shutdown is required.

Surveillance Requirements 4.7.5b a.nd d were also revised to reflect these changes.

4. LCO 3.7.5d was revised to reflect the new limit on UHS cooling tower basin temperature of 88'F based on the findings of the UHS cooling tower performance test.

The associated Action Statement d was also revised.

Also a note that is no longer appilcable is being deleted.

5. LCD. 3.7.5e was added to provide a means of distinguishing a failed basin limit switch from essential service water makeup pump inoperability.

The associated action statement was also revised.

6. Surveillance Requirements 4.7.4.lb, 4.7.5e.2) and e.4) were revised to l

add the words "at least" before "15 minutes" or "30 minutes" to clarify 4

that it is acceptable to run the pumps for at least 15 or 30 minutes rather than for exactly 15 or 30 minutes.

7. Bases Section 3/4.7.5 was updated to clarify certain descriptions and incorporate a discussion of the changes made to the UHS Specification 3.7.5.

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t ATTACHMENT C (Continued)

None of the proposed changes are initiating events, therefore, the probability of occurrence of an accident previously evaluated is not affected.

Changes 1, 6, and 7 are administrative or editorial in nature so they do not affect the consequences of any accident previously evaluated. Change 2 allows a mode change when operating in an Action Statement.

This Specification requires an ESH pump from a unit in Modes 5 or 6 to be available to support operation for the other unit operating in Modes 1-4.

This is in addition to the two ESH pumps required to t

be operable per Specification 3.7.4.

Any one of the three pumps can supply 100%of l

the ESH requirement.

The provisions of 3.0.4 is applicable to Specification 3.7.4

~

so mode changes are not permitted when one of the two " normal" ESH pumps are Inoperable.

It_is overly restrictive to not permit a startup when a third pump from the shutdown unit is unavailable.

Especially since the Action Statement also has a time limit on continued operation.

Another consideration is that the heat load required to be handled by the ESH system is minimized because the design is to handle one unit undergoing a LOCA with the other unit proceeding to a normal shutdown.

The condition when a pump is required to be available occurs when one unit is in Modes 5 or 6 so there is no heat load for this unit undergoing a shutdown because it is already operating at a temperature less than or equal to 200*F.

Therefore, this change does not involve a significant increase in the consequences of an accident previously evaluated.

Changes 3 and 4 also do not involve a significant increase in the consequences of an accident previously evaluated.

The UHS is designed to remove the heat load from a design basis LOCA in one unit and a LOOP with normal shutdown in the other unit without exceeding an ESH pump discharge temperature of approximately 98'F.

This ensures the maximum acceptable ESH pump discharge temperature limit of 100'F is not exceeded.

The revision included in Changes 3 and i

4 are based on data taken during the UHS cooling tower performance test and subsequent calculations.

This information is documented in the Byron Station Essential Service Hater Cooling Tower Performance Test Program report.

Changes 3 and 4 revise the Technical Specifications to reflect actual cooling tower performance while not exceeding or altering the maximum acceptable ESH pump discharge temperature limit.

7 Change 5 provides an alternate method co maintain required UHS cooling tower basin level when a basin level switch fails prcrenting essential service water makeup pump automatic start on low basin level.

Basin level is increased to a point that a surveillance can adequately monitor that the limit of 50% is not violated.

During this period the makeup pumps would be operable to start manually.

Because the essential service water makeup pumps are still operable to supply makeup to the VHS cooling tower basin and additional contingency measures have been added during the period of operation with a failed basin level switch, the consequences of an accident previously evaluated have not been significantly increased.

l Since changes 1, 6, and 7 are administrative or editorial in nature they do not create the possibility of a new or different kind of accident from any accident previously evaluated. Change 2 does not involve any modifications to the system or result in any new or different modes of operation so the possibility of a new or different kind of accident is not created.

Change 3 and 4 ensure that the design basis of the VHS can be satisfied by changing the required number of fans operable coupled with UHS cooling tower basin temperature limits.

Equipment is not modified

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ATTACHMENT C (Continued) or physically operated differently, merely the temperature limits at which different conditions of operation are permitted have been revised and this does not involve a new or different type of acc1( 4 Change 5 does not involve a modification to any system.

The change

,.ws an alternative action for a failed level switch and does not create the po. 6 lity of a new or different kind of accident.

The proposed changes will not affect the operation of the ESH system or UHS and therefore, do not create the possibility of a new or different type of accident.

Changes 1, 6, and 7 are administrative or editorial in nature and do not affect a margin of safety.

Change 2 allows a change in mode when one of three redundant, 1001 capability ESH pumps is not operable.

Since the heat load required to be dissipated under this condition is less than the design limit heat load and operation in this condition is limited to seven days, the margin of sPfety is not significantly affected.

Changes 3 and 4 revise the Technical Specifications to reflect the demonstrated performance of the VHS cooling towers.

The design condition of ensuring that the UHS removes the heat loav from a design basis LOCA in one unit and a LOOP with normal shutdown in the other unit without exceeding an ESH pump discharge temperature of approximately 98'F so that the maximum acceptable ESH pump discharge temperature limit oi 100'F is not exceeded is not affected by these changes.

Changes 3 and 4 update the Technical Specifications to reflect cooling tower performance without altering or violating the design limits of the ESH system and UHS and ti.erefore do not affect the margin of safety.

Change 5 allows essential service water makeup pump operation with a failed level switch.

Compensatory measures will be implemented which require the basin level to be increased and maintained at a higher level than is normally required and the surveillance frequency will be increased during this period.

Therefore, this change will not reduce the margin of safety.

Therefore, based on the above considerations, Comraonwealth Edison has determined that these changes do not involve a significant hazards condition.

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AUAGHMENT Q ENVIRONMENTAL _ ASSESSMENT The proposed Technical Specification amendment involves several. changes.

Byron Station has evaluated the proposed amendment against the criteria for and identification of licensing and regulatory actions requiring environmental-assessment in accordance with 10CFR51.21.

It has been determined that the proposed changes meet the criteria for a categorical exclusion as provided for under 10CFR51.22(c)(9) and (10).

Following is a discussion of the changes and how they meet the criteria-for categorical exclusion.

The thange to Specification 3.7.4.1 adds that the provisions of Specification 3.0.4 are not applicable.

The addition of this note allows a unit to change modes when operating in an Action Statement.

Specification 3.7.4.1 requires an ESH pump on a unit in Modes 5 or 6 to be available to support the two normally operable ESH pumps for the other Unit in Modes 1-4.

This involves a change in the j

use of a facility component located within the restricted area and a change in a surveillance requirement.

The changes to LC0's 3.7.5b ACTION's b and d and Surveillance Requirements 4.7.5b and d were made to reflect the demonstrated performance of the UHS cocling towers based on test results.

The number of fans required to be operable in the high speed mode is dependent on VHS cooling tower basin temperature.

These revisions also involve a change to the use of a facility component located within i

the restricted area and to a surveillance requirement.

The changes to LCO 3.7.5e and Action e differentiate the requirements for essential service sater makeup pump inoperability due to a failed basin level switch versus othei teasons.

This involves a change to the use of a facility component located within the restricted area.

The preceding changes do not involve a significant hazards consideration as discussed in Attachment C of this letter.

Also there are no significant changes in the types or significant increase in the amounts of any effluents that may be released off-site since these changes do not affect the generation of any radioactive effluents nor do they affect any of the permitted release paths, finally the changes do not involve a significant increase in individual or cumulative occupational radiation exposure.

The majority of changes were made to ensure the demonstrated performance of the ESH system and UHS remain within the design basis assumptions.

Therefore, these changes meet the categorical exclusion permitted by 10CFR51.22(c)(9).

The remaining changes are essentially changes in administrative requirements and therefore meet the categorical exclusion permitted by 10CFR51.22(c)(10).

The changes to Specification 3.7.4 were to relocate the cooling tower requirements to Specification 3.7.5.

The changes to Surveillance Requirement 4.7.4.lb, 4.7.Se.2) and e.4) were clarifications in the wording of the Specifications, i

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