Text

Proposed Tech Specs,Modifying TS 3/4.7.4 Ultimate Heat Sink by Incorporating More Restrictive Fan Operability Requirements & Lower Basin Temp
	ML20116B051
Person / Time
Site:	Waterford
Issue date:	07/25/1996
From:	; ENTERGY OPERATIONS, INC.
To:	;
Shared Package
ML20116B049	List: ML20116B046; ML20116B051;
References
	NUDOCS 9607290080
	Download: ML20116B051 (9)
	v • d • e

PLANT SYSTEMS 3/4.7.4 ULTIMATE HEAT SINK LIMITING CONDITION FOR OPERATION I

3.7.4 Two independent trains of ultimate heat sink cooling towers shall be i

OPERABLE with each train consisting of a dry cooling tower (DCT) and a wet l

mechanical draft cooling tower and its associated water basin with:

4 f

a.

A minimum water level in each wet tower basin of 975 (-9.86 ft MSL) b.

An average basin water temperature of less than or equal to 9S*F.

c.

Fans as required by Table 3.7-3.

]

APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTION:

a.

With one wet mechanical draft cooling tower inoperable due to low water level and/or high average water temperature, restore the wet mechanical draft cooling tower to OPERA 8LE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in NOT 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 wet mechanical draft cooling towers inoperable due to low water level and/or high average water temperature, restore at least i

one wet mechanical draft cooling tower to OPERA 8LE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and restore both wet mechanical draft cooling towers to OPERABLE statu, within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months of initial loss, otherwise be in at least HOT STAND 8Y within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

c.

With the number of OPERABLE fans less than required by Table 3.7-3 on !

one DCT/WCT train, restore the number of OPERABLE fans to within the i

requirements of Table 3.7-3 within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months (except as specified in Action e.), or be in HOT STAND 8Y 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 .

d.

With the number of OPERA 3LE fans less than required by Table 3.7-3 on both DCT/WCT trains, restore the number of OPERABLE fans to within the requirements of Table 3.7-3 for 1 DCT/WCT train within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and comply with ACTION c. (except as specified in ACTION e.), or be in HOT STAND 8Y within sne 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 .

h$g72}gggog8 2

P WATERFORD - UNIT 3 3/4 7-12 Amendment No.

w 4

PLANT SYSTEMS LIMITING CONDITION FOR OPERATION (Continued)

ACTION:

(Continued)

With a Tornado Watch in effect, and the number of fans OPERABLE e.

within the missile protected area of a DCT less than that required by Table 3.7.3, restore the inoperable fan (s) to OPEPABLE status within I hour, or be in at least NOT STAND 8Y within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

~

f.

With more than one fan inoperable and the outside at: temperature greater than 70*F, determine the dry bulb temperature at least once every 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months .

If the temperature is 2 80*F, determine the wet bulb temperature and verify that the minimum fan requirements of Table 3.7-3 are satisfied.

SURVEILLANCE REQUIREMENTS 4.7.4.

Each train of ultimate heat sink shall be detemined OPERABLE:

At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by verifying the average water temperature a.

and water level to be within their limits.

b.

At least once per 31 days, by serifying that each wet tower and dry tower fan that is not already running, starts and operates for at least 15 minutes.

~

WATERFORD - UNIT 3 3/4 7-13 AmendmentNo.g

TABLE 3.7-3 DLUMIE HEAT SINK MINIMUM FAN REQUIREENIS ORY BULB 2 90*F 80*F 5 DRY BUL8 < 90*F DRY SUL8 < 80*F AfslENT I

GR Als C01BITIO11 IfET OULB 2 81*F K T BUL8 < 81*F Fan 14 KT"* and 12 DCT*** and 9 KT** and l

Requirements"3 8 KT 4 KT*

4 KT*

OR 15 KT and 7 K T*

IIOTE: With more than one fan inoperable comply with ACTION f.

l l

(I) All fans of a dry cooling tower section are inoperable if component cooling water is secured to that section. -

With any KT fan (s) out-of-service in any cell, covers must be in place on the out-of-service fan (s) or the entire cell (i.e. 4 fans) declared out-of-service.

With a tornado watch in effect, at least 8 of the DCT fans under the missile protected portion of the l

DCT shall be OPERABLE.

With a tornado watch in effect, all 9 DCT fans under the missile protected portion of the DCT shall be l

OPERABLE.

l

l PLANT SYSTEMS BASES 3/4.7.4 ULTIMATE HEAT SINi(

The limitations on the ultimate heat sink level, temperature, and number of fans ensure that sufficient cooling capacity is available to either (1) provide normal cooldown of the facili.ty, or (2) to mitigate the effects of accident conditions within acceptable limits.

The UHS consists of two dry cooling towers (DCTs), two wet cooling towers (WCTs), and water stored in WCT basins.

Each of two 100 percent capacity loops employs a dry and wet cooling tower.

Each DCT consists of five separate cells. Cooling air for each cell is provided by 3 fans, for a total of 15 per DCT.

The cooling coils on three cells of each DCT (i.e. 60%) are protected from tornado missiles by grating located above the coils and capable of withstanding tornado missile impact.

With a Tornado Watch in effect and the number of fans OPERABLE within the missile protected area of a DCT less than that required by Table 3.7-3, ACTION e requires the restoration of inoperable fans within I hour or plant shutdown as specified.

This ACTION is based on FSAR analysis (subsection 9.2.5.3.3) that assumes the worst case single failure as,1 emergency diesel generator coincident with a loss of offsite power. This failure occurs subsequent to a tornado strike and 60% cooling capacity of a DCT is assumed available.

Each.WCT has a basin which is capable of storing sufficient water to bring the plant to safe shutdown under all accident conditions.

Item a of LCO 3/4.7.4 requires a minimum water level in each WCT barin of 97% (-9.86 ft MSL).

The bases for this elevation is WCT water evaporation and drift loss calculations, which concludsd that during a LOCA 173,930 gallons would be evaporated from one WCT basin. When the WCT basin water level is maintained at

-9.86 ft MSL, each basin has a minimum capacity of 174,000 gallons.

Each WCT consists of two cells, each cell is serviced by 4 induced draft fans, for a total of 8 per WCT.

There is a concrete partition between the cells that prevents air recirculation between the fans of each cell. Covers are required on fans declared out-of-service to prevent air recirculation between fans within a cell.

Table 3.7-3 specifies increased or decreased fan OPERABILITY requirements based on outside air temperature and humidity.

Because temperature and humidity are subject to change during the day, ACTION f requires oer; odic temperature readings to verify compliance with Table 3.7-3 when more than I fan is inoperable.

When outside air temperature (DRY BULB) is 1 80*F, WET BULB readings are necessary to ensure increased OPERABILITY requirements are met when WET BULB 2 is 81"F.

~;..

Trie limitations on minimum water level and maximum temperature are based on providing a 30-day cooling water supply to safety-related equipment without exceeding their design basis temperature and is consistent with the recommend-ations of Regulatory Guide 1.27, " Ultimate Heat Sink for Nuclear Plants,"

March 1974.

WA1ERFORD - dNIT 3 B 3/4 7-4 AMENDMENT NO. 95 O

l

Jea-A

.L.

.Aa.,,m u,..

ma

-s 4

..a_,.a ms m

c.+_.m..

D 0

4 4

4 l

l I

i l

l i

}

t l

l 1

\\

I t

i 4

l l

NPF-38-180 l

i l

ATTACHMENT B i

i.

i

+

4 PLANT SYSTEMS l

3/4.7.4 ULTIMATE HEAT SINK (VHS) l t

LIMIT]NG CONDITION FOR OPERATION r

l 3.7.4 Two independent trains of u'ti=te heat Sink UHS sco'ing towers shall be OPERABLE w i th. ^ _'-". +.. w' 4. - ^^^"4.*,+.4..^,

^ #.

w' d,.~, ^^^'.4..^.^,

+ ^ ".. ^ - ', n".T. '

w'".

w' ".. ^ +..

.v..

.v

,. d

..^^"..,'.".4.^w.

d. w' #. +.

w Cna14. n.n,

+ nu,n e / U..f'T.,i

.s.n..d 4. +~e _s e.e nr 4. w. w,. us+n.e

.h s e 4..n.u. i. t.h.

staA vv

.v s

v w

-w..

~

a.

A minimum water level in each wet tower basin of 97% (-9.86 ft MSL) b.

An average basin water temperature of less than or equal to %_8fF.

c.

Fans as required by Table 3.7-3.

APPLICABILITY: MODES 1. 2, 3, and 4.

ACTION:

a.

With 1_,ene UHS train inoperable wet =chanical draft cooling tower inoperable A...n

, nm.. m,s. +. m.,mn, w..w.sna/m.

+m h 4. n,h.. w n-sa,n m.. w, +.m. +n nn..,+".^. restore _the

.v v.

.. w.

.w...r inoperable train to the wet =chanical draft-c00 ling tower OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in 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 UHS trains wet =chanical draft c0014ng tower: inoperable due-te4ew water-4 eve' and/or high average water tem.perature, restore at least one Ul@

train wet = chanica' draft c0014ng tower to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and g e. n hn+h.

u.. n +m..ne k. u Tsn i. e s1 A e.sf+Wran14n.n + nu.. n c.W

+n ADED. VADt E e, + s + a c u 4. + h. 4 n

7. >9 WVV-

&V e

g y V y.

b y hb.

bw W

W.

yV y.

h, MWb b g bubWW hours c' 4att4:1 10 0, Othe wice_o)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 COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

6.

U 4. +.h.+ h.n m.wm...h, n, e,n #. AD rD. yA.DI E ( s n. e.

i. n r e,

+ h, w., ram.i 4. e. nA hu T.ww.n 97 9 shi v

y nn.

nn.a.

... w.

v v.

.w.

s.

.. sn

.sy ww wj w

v.

w DGT4WGT-train, restore the nu=ber of OPEP.^3LE fans to within the requi-r-ements shi nf. T.uu.n 97 9 u4+h.4n.

7, 9 h.m ic e, ( n.,e

+ se e nne i. f, 4. ad. 4. n.

.A.i., vT v.. n.i. Or uw rti^n hn

4. n. WAT w v v

rt

.v sw.w w,

w,

.vr v

,yww ww C T. A U.h D V.u. 4. +..h 4. n.+hn

.n.n v,.

h.m i r..e, sn. A

4. n. f' Af n C u..f fTNAL..fk. ! u i. +.h.. i. n.

+ h.a

. r.1 1. nu.i i..n,

+ f 4n On v

-w

...w wr v

.v w1 w vvww v vivv

..w v

v vv h6ur6-d.

Wi-th-the num.ber Of OPEMBLE-fans 4ess-than required-by Table 4.' 3 On both nrT. /U..f'T.

+rs4ne e n e., + n ca.

+ h. n,. m.w..w w.

v.

w...,.

.s v.

... imhne nf. AD. rD A.DI E #sn.e,

+n u 4 + h.4. n

..h.n cam i 4. r n m...w..+.6

+

an rT~

s syw. w v

v m.v w.

.,v n f. T.wyshi. n 97 9 (^ r. 1 Nf'T /U..f'T. + r si n u 4. +.h. 4 n 1 k.m, e w..w ni o snA enmy.g

._.4.+.h..A f*T. T Akit e.

v w -

v

-v w

u..

. ww.

vvo iv

.v

+

/n,enn+

se e,nnr 4. #, 4. nA 4m.A f'T. T AM, n.f hn.

-.- U. nT. CT. A ktnDV.

i nr w

v v

.-- -. 4 t h. 4. n +hn in D

n.

.w sunswy.

w, yww ww v. vi w

v.

hours and in-GOLD SHUTDOW4-w4-th4n-the-.foMow4ng40-hour-sT WATERFORD - UNIT 3 3/4 7-12 AMENDMENT "0. 95 l l

l

PLANT SYSTEMS LIMITING CONDITION FOR OPERATION (Continued)

ACTION: (Continued)

_c_e.

With a Tornado Watch in effect, all 9 DCT fans under the missile protected portion of the DCT shall be OPERABLE. IF and the number of fans OPERABLE _Ls within the -istle protected are: Of : DCT less than--that required, by-Table 3.' 3 restore the inoperable fan (s) to OPERABLE status.within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months , or be in at least HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months , d f.

With any UHS =cre than One fan inoperable and the Out+4dc air te perstwe-greater tha _76*Fr determine the outside ambient dry bulb temperature at least once every 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months . F the te per:ture is-t-80'F. deter =" the uct bulb te perstwe-and verify that the minimum fan requirements of Table 3.7-3 are satisfied.

SURVEILLANCE REQUIREMENTS 4.7.4.

Each train of UHS ultimate heat cink shall be determined OPERABLE:

l a.

At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by verifying the average water temperature and water level to be within specified the# limits.

l b.

At least once per 31 days, by verifying that each wet tower and dry tower fan that is not already running, starts and operates for at least 15 minutes.

WATERFORD - UNIT 3 3/4 7-13 MENOMENT-40-95 l

TABLE 3.7-3 ULTIMATE HEAT SINK MINIMUM FAN RE0'JIREMENTS PER TRAIN DRY COOLING TOWER AMBIENT CONDTTION DRY BULB 2 98 F

< 98 F DRY BULB 2 91*F

< 91 F DRY BULB 2 77'F DRY BULB < 77 F Fan 15 14*

12*

9*

Requirements (1)

WET COOLING TOWER AMBIENT CONDITION WET BULB 2 75 F

< 75'F WET BULB 2 70*F WET BULB < 70 F Fan 8

7**

4**

Requirements (1)

(1)

With any of the above required UHS fan inoperable comply with ACTION d.

With a tornado watch in effect all 9 DCT fans under the missile protected portion of the DCT shall be OPERABLE.

With any WCT fan (s) out-of-service in any cell. covers must be in place on the out-of-service fan (s) or the entire cell (i.e.

4 fans) must be declared out-of-service. If four fans are out of service in the same cell, the covers do not have to be installed.

WATERFORD - UNIT 3 3/4 7-14 AuENDwENT NO. 95 l

~

PLANT SYSTEMS BASES 3/4.7.4 ULTIMATE HEAT SINK The limitations on the ultimate heat sink level, temperature, and number of fans ensure that~ sufficient cooling capacity is available to either (1) provide normal cooldown of the facility, or (2) to mitigate the effects of accident conditions within acceptable limits.

The UHS consists of two dry cooling towers (DCTs), two wet cooling towers (WCTs), and water stored in WCT basins. Each of two 100 percent capacity loops employs a dry and wet cooling tower.

Each DCT consists of five separate cells. Cooling air for each cell is provided by 3 fans, for a total of 15 per DCT. The cooling coils on three cells of each DCT (i.e. 60%) are protected from tornado missiles by grating located above the coils and capable of w'thstanding tornado missile impact. With a Tornado Watch in effect and the number OT fans OPERABLE within the missile protected area of a DCT less than that required by Table 3.7-3, ACTION e requires the restoration of inoperable fans within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or plant shutdown as specified. This ACTION is based on FSAR analysis (subsection 9.2.5.3.3) that assumes the worst case single failure as 1 emergency diesel generator coincident with a loss of offsite power. This failure occurs subsequent to a tornado strike and 60% cooling capacity of a DCT is assumed available.

Each WCT has a basin which is capable of storing sufficient water to bring the plant to safe shutdown under all accident conditions. Item a of LC0 3/4.7.4 requires a minimum water level in each WCT basin of 97% (-9.86 ft. HSL). The bases for this elevation is WCT water evaporation and drift loss calculations. which concluded that during a LOCA 473r930 168.738 gallons would be consumed evaporated from one WCT l

basin. When the WCT basin water level is maintained at -9.86 ft. HSL each basin has -

a minimum capacity of 174,000 gallons. Each WCT consists of two cells, each cell is serviced by 4 induced draft fans, for a total of 8 per WCT. There is a concrete partition between the cells that prevents air recirculation between the fans of each cell. Covers are required on fans declared out-of-service to prevent air recirculation between fans within a cell.

Table 3.7-3 specifies increased or decreased fan OPERABILITY requirements based on outside air temperature and humidity. The table provides the cooling tower fan OPERABILITY reauirements that may vary with outside ambient conditions. Fan OPERABILITY requirements are specified for each controlling parameter (i.e.. dry bulb temperatures for DCT fans and wet bulb temperatures for WCT fans). The calculated temperature values (EC-M95-009) associated with DCT and WCT fan requirements have been rounded in the conservative direction and lowered one full degree to account for minor inaccuracies. Failure to meet the OPERABILITY requirements of Table 3.7-3 reauires entry into the applicable action. Because temperature and humidity are subject to change during the day. ACTION _df requires periodic temperature readings to verify compliance with Table 3.7-3 when any cooling tower Ore than ' fan is inoperable.

!?e" outside 21" te p^rature (DRY BULB) i s 2 80*..... _. -...,.

.._r-y-te ensure 4ncre: 00 OPEPABILIN requir=nts are etwhen WET SULB-2-4s41*Fr The limitatio s on minimum water level and maximum temperature are 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.

WATERFORD " UNIT 3 8 3/4 7-4

/K NDHE#T NO 95 l

ML20116B051

Text

Navigation menu

Search