ML20082M550

From kanterella
Jump to navigation Jump to search
Proposed Tech Spec 3.7.1.3, Auxiliary Feedwater Storage Tank, Changing Min Vol Requirement from 518,000 to 485,000 Gallons
ML20082M550
Person / Time
Site: South Texas  STP Nuclear Operating Company icon.png
Issue date: 08/26/1991
From:
HOUSTON LIGHTING & POWER CO.
To:
Shared Package
ML20082M537 List:
References
NUDOCS 9109050250
Download: ML20082M550 (5)
v • d • e


Text

. . , . - . . - - - - _. - -

- f

~

i STPEGS OFSAR _ _ - [

jJMhMEld 3 l SHIL AE 3P 6 / i PAGE _L - 0F 2 _

Qgestion.440.30N ,

With regard to the information in Appendix 5.4.A " Cold Shutdown capabilitya identify the most limitin6 single failure with regard to cooldown capability and verify that the statement of Table 5.4. A 1 that the auxiliary feedwater storage tank (AFST) " capacity of 500,000 gallons is adequate to support 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> at hot standby conditions followed by 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> cooldown to PJiR cut in condition with a margin for contingencies" coni.iders this failure. ,

[

Etrucar - ,

%4/5 &/7_. _

l eThe~tnost 11miYliiig~Tdilutrregardinfso16wn time is the loss of "A"-triin AC -i power, which results lu the loss of two stearn generator p0$Vw-Tfic AFST l usable capacity of $25,000 gallons is adequate to support'4 hourn at hot '{

standby, a 14 bour cooldovn, followed by depresyurtfation to RHR conditions i with a margin for contingencies, A maximtyn-of 377,000 gallons of water would i eneratT6s dering this period, I I

be added to the effective steam g /

TheAFSTsizingconsiderspossiblelevelinstrumenterror,vaterdeliveredto a faulted steam generator 7 water lost through the turbine lube oil cooler, j various small s flange or pump seal leakage), and a  !

(inargin agajust'yyteti vortex formation. water losses The minimum (i.e. , usable volume in the AFST above {

j i

(thesucetonnozzlesis443,000 gallons, I

Db. - . -. - - . - - - . .

f i

t i

f l.

t i

f 1 i i- l l

l I F

i l

l -;

f

,- c j i

i i

Q&R 5.4 13 Revision 0 t 9109050250 9i0826 i

l. ADOCK 05000498

-PDR  !

-P PDR

,,w.,+-ce,-p r- ., w ,y- -,.w, .-,w.-ym.em,-m-w,-,.,-,,,..-,.e--..w,,.w~~,-,.----v.,,e.wn*,,,-w

ma M vu.,nMliN13 i

Sl HL AE 324 / '

. PAGE L OF 2 i

s t0G F 12 Y The most limiting failure regarding cooldown time is a 14ain Feedwater )

Line Break (MFLB) with a failure of an Auxiliary Feedwater flow control valve. T The flow control valve failure in the open position maximj tes the water added to

, the steam generator with the MFl.B. The amount of water t o ded for energy removal and cooldown would bc <376,000 gallons with a total time to RllR cut in 1 of <21 hours. A cooldown of 25'F/hr can be accomplished with the remaining three steam generators. The corresponding miscellaneous lossen at 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> is 95,000 gallons to define a total AFST water volume of <471,000 gallons. The AFST usable capacity of 525,000 is adequate to support this limiting condition.

j =- i t

4 s n

?

L 4

f 1

, 'A1/027.NL9

.-. ~ , _ _ . , . . . . . _ . _ , ._~..,._.,_._,_,._,_u...., , , . - _ , _ . . , . . . . , . . _ . . . _ _ _ _ . _ . , , _

"'_MwWMa+.".0W-puM.ser-6mA # ai4 A44 4 + . ,m 4Ah m.

I l'

.. *- , i 6

l 4

l. {

9 i

6 t

'.I

?

t.

.. ?

r

-6 J

f.

F l

f ATTACitMENT 4 l t

PROPOSED CllANCE TO TECIINICA1. SPECIFICATION 3,7.1.3

' Az P

h

.T k

I i

r P

k P

P

-8

'l i

i e

i 1

I t

i 4

Al/027,NL9 .  !

I L

-6 b

, ,-n -+,e-,. .-+,,-an. ->a-, m n,-

..n.-,..,nna,.w,.--, ,.'w,,...,ne.,,.v'-.,,.,<,i..n-. ...n_-- - .. ..- - , -,,, ,.-..--- - -- - , - . ,-,-~ n- , - -,-

0 , .

i kapC4 MENT 4

, r3 tail Systifis Sf hl AE-3F4 /

, PAGE.-i 0F __ 2 Aux]ll ARY F l[0L'Al[R STORAG[ 1 ANK i

i klMlllfi,0.0ENIJQMJOR OPLM110N .

3. 7.1. 3 lhe auxiliary feedwater storage tank (AFST) shall be OPERABLE with a contained water volume of at least 4167{$0 galions of water. j APPt}CABlllTY:

MODES 1, 2, and 3. q g g O i AC110N:

With the AFS1 inoperable, within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> restore the AFST to OPERABLE status or be in at least H01 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 H01 SHUTOOWN within the following ) hours.

181Ill1g[CLf1Byf1ME!R$ mm m====-

i

~ ~ = = = 1

4.7.1.3 The AFS1 shall be demonstrated OPERABLE at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by
verifying the contained water volume is within its limits. ,

_l

! l t(

J 4

4 i

SOUTH TEXA5 - UN115 1 & 2 3/4 7- f>

a .., .

PLANT $151 EMS ATTACliME5i 7

, ST HL AE M4 / i PAGE _. L .OF 1  !

MML_._ _m__ _

f' 3/4.7.1.2 AUX 1tl ARY FEEDWA1ER SYS1EH The-0PERABILITY of the Auxiliary feedwater System ensures that the Reactor >

l'oolant System can be cooled down to less than 350*F from normal operating i conditions in the event of 'a total loss-of-offsite power. -

Each auxiliary feedwater pump is capable of delivering a total feedwater I flow of $40 gpm at a pressure of 1324 psig to the entrance of the steam genera-  !

tors. This capacity is sufficient to ensure that adequate feedwater flow is-  !

- available to remove decay heat and reduce the Reactor Coolant System tempera-  ;

ture to less than 350*F when the Residual Heat Removal System may be placed  ;

into operation. The ATV pumps are tested usit g the test line back to the ATST  !

and the AfW isolation valves closed to prevent injection of cold water into i the steam generators. .The 51 PEGS isolation valves are active valves required  !

to open on an AfW actuation signal. Specification 4.7.1.2.1 requires,these  :

valves to be verified in the correct position.  !'

3/4.7.1.3 AllXILI ARY FEE 0 WATER STORAGE TANK (AFST) l

~

The OPERABILITY of the auxiliary feedsater storage tank with the minimum j 9ater volume ensures that sufficient water is available to maintain the RCS at i HOT STANDBY conditions for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> with steam discharge to_ the atmosphere

. concurrent with total loss-of-of fsite power followed by a cooldown to 350'T at

.25'F per hour. The contained water volume limit includes an allowance for  ;

water not usable because of tank discharg line location or other physical l characteristics, j g p g 3/4.7.1.4 *'

SPECIIlibACflVI Y gg ,

The limitations on Secondary Coolant System specific activity ensure that  ;

the resultant offsite radiation dose will be limited to a small fraction of  !

10 CFR Part 100 dose guidelis values in the event of a steam line rupture. [

This dose also includes the ef fects of a coincident 1 gpm primary-to-secondary  ;

tube leak in the steam generator of the affected steam line. These values are  !

consistent with the assumptions used in the safety analyses.

3/4.7.1.5 MAIN STEAM LINE_ ISOLATION VALVES j The OPERABILITY of the main steam line isolation valves ensures that'no l

, more than one steam generator will blow down in the' event of a steam line -r L rupture. This restriction is required to: (1) minimize the positive reac--  !

!' tivity effects of the Reactor Coolant System cooldown associated with the _!

l _ blowdown, and (2) limit the pressure rise within containment in the event the  !*

steam line rupture occurs within containment. The OPERABIllTY of the main L steam isolation valves within the closure times of the Surveillance Require- [

ments are consistent with the assumptions used in the safety analyses, j I

i i

SOUTH TEXAS - UNITS 1 & 2 B 3/4 7-2 .

f l  !

l t

L k

_

Retrieved from "https://kanterella.com/w/index.php?title=ML20082M550&oldid=2749584"