Text

Proposed Tech Specs Changes for SQN Units 1 & 2 & for Change Boric Acid Concentration Reduction.
	ML20044B996
Person / Time
Site:	Sequoyah
Issue date:	03/10/1993
From:	; TENNESSEE VALLEY AUTHORITY
To:	;
Shared Package
ML20044B994	List: ML20044B993; ML20044B996;
References
	NUDOCS 9303160081
	Download: ML20044B996 (230)
	v • d • e

- ~ . . - . . . - -

l- !

-l i

I ;

I ENCLOSURE 1 I PROPOSED TECHNICAL SPECIFICATION CHANGE !

l SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (TVA-SQN-TS-92-08) '!

LIST OF AFFECTED PAGES Unit 1 i 3/4 1-1 3/4 1-3 l 3/4 1-7 !

3/4 1-8 I 3/4 1-11 3/4 1-12 1 3/4 1-13 '

3/4 1-13a ,

3/4 9-1 3/4 10-1. ;

B3/4 1-2 !

i B3/4'l-3 !

l' !

l l Unit 2 i 3/4 1-1 !

3/4 1-3 i 3/4 1-7 j 3/4 1-8 '

3/4 1-11 3/4 1-12 j 3/4 1-13' i 3/4 1-13a .)

3/4 9-1 1 3/4 10-1 B3/4 1-2 B3/4 1-3 9303160081 930310 9 PDR ADOCK 05000327 .~

P PDR _g

\

~

(

3f4.1 REACTIVITY CONTROL SYSTEMS 3/4.1.1 BORATION CONTROL SHUTDOWN MARGIN - T,yg Greater Than 200'F LIMITING CONDITION FOR OPERATION 3.1.1.1 The SHUTDOWN MARGIN shall be greater than or equal to 1.6% delta k/k for 4 loop operation.

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

ACTION:

M 3f G#M j With the SHUTDOWN MARGIN less than 1.6% delta k/k, immediately initiate and continue boration at greater tnan or equal tono p; of a solution containing

/20,000 ;;- boren or equivalent until the required SHUTDOWN MARGIN is restored.

lGRvWlaR TNM ** artPM4 7b 4/2ega, SURVEILLANCE REQUIREMENTS i

4.1.1.1.1 The SHUTDOWN MARGIN shall be determined to be greater than or equal ,

to 1.6% delta k/k:

a. Within one hour after detection of an inoperable control rod (s) and i at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter while the rod (s) is inoperable. !

If the inoperable control rod is immovable or untrippable, the above required SHUTDOWN MARGIN shall be verified acceptable with an increased allowance for the withdrawn worth of the immovable or untrippable control rod (s). i

b. When in MODE 1 or MODE 2 with K greater than or equal to 1.0, at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by veri?yIng that control bank withdrawal is within the limits of Specification 3.1.3.6.

c. When in MODE 2 with K less than 1.0, within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months prior to achievingreactorcrikkbalitybyverifyingthatthepredicted critical control rod position is within the limits of Specification 3.1.3.6.

TP "See Special Test Exception 3.10.1 SEQUOYAH - UNIT 1 3/4 1-1 SEP 171980 t

I

_ , + - , ,

4 REACTIVITY CONTROL SYSTEMS SHUTDOWN MARGIN - T,yg Less Than or Equal to 200*F I

LIMITING CONDITION FOR OPERATION 3.1.1.2 The SHUTDOWN MARGIN shall be greater than or equal to 1.0% delta k/k.

APPLICABILITY: MODE 5.

ACTION:

p pg i

With the SHUTDOWN MARGIN less than 1.0% delta .k/k, immediately initiate ana l

l continue boration at greater than or equal to le ;;r of a solution containing R16 l greater than or equal to d20.000 ;;r or equivalent until the required SHUTDOWN MARGIN is restored.

(,1zo ppw E* A o^!

SURVEILLANCE REQUIREMENTS 4.1.1.2 The SHUTDOWN MARGIN shall be determined to be greater than or equal i

to 1.0% delta k/k:

i a. Within one hour after detection of an inoperable control rod (s) and ,

l at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter while the rod (s) is inoperable.

l If the inoperable control rod is immovable or untrippable, the l SHUTOOWN MARGIN shall be verified acceptable with an increased allowance for the withdrawn worth of the immovable or untrippable control rod (s). !

b.

At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by consideration of the following factors:

1. Reactor coolant system boron concentration,

2. Control rod position,

3. Reactor coolant system average temperature,

4. Fuel burnup based on gross thermal energy generation,

5. Xenon concentration, and

6. Samarium concentration.

I l

i h4AJ1251982 SEQUOYAH - UNIT 1 3/4 1-3 Amendment No.12 y . w -

REACTIVITY CONTROL SYSTEMS

-I 3/4.1.2 BORATION SYSTEMS FLOW PATHS - SHUTDOWN LIMITING CONDITION FOR OPERATION 1 l

i 3.1.2.1 As a minimum, on' if the following-boron infection flow paths shall !

be OPERABLE:

a. A flow path from the boric acid tank via a boric acid transfer pump l and charging pump to the Reactor Coolant System if only the boric j acid storage tank in Specification 3.1.2.5a is 0PERABLE, or

b. The flow path from the refueling water storage tank via a charging j pump to the Reactor Coolant System if only the refueling water i

storage tank in Specification 3.1.2.5b is OPERABLE. ;

i I j APPLICABILITY: MODES 4, 5 and 6. j j ACTION:

R161 MODE 4 - With none of the above flow paths OPERABLE, suspend all operations l involving CORE ALTERATIONS or positive reactivity changes and restore !

..- one flow path as soon as possible. !

l'(W i

MODES 5 "ith none of the above flow paths'0PERf8LE, suspend all operations i f and 6 involving CORE ALTERATIONS or positive reactivity changes. !

l i

SURVEILLANCE REQUIREMENTS :,

I i

At least one of th aths s_ hall be demonstrated i

- gens cearnw wG o: Lou mm ewwn FW Tu nome new wa ro nc ;

\ w -

^A M w o,as, rgg :

l a. At least once per 7 days by verifying that the temperature of.the i

, 63er heet triced pcrtier Of the f h; pcth is greater'-than or equal to m or l wh e n . . -._ r.". '. '. . .. ". . .. .' .- . #. .- . ' . ' ' .. . . . ~ ' . - - . ,. . . " .

M At least once per 31 days by verifying that each valve (manual, power operateci or automatic) in the flow path that is not locked, sealed, j!

c. or otherwise secured in position, is in its correct position. ;

,, ,, e tzcQm u'AM S *" M*

I i

)

l 1

.y ;

1 l

SEQUOYAH - UNIT 1 3/4 1-7 Amendment No.157 )

l March 30, 1992 i t

l l

! 1

. I i

REACTIVITY CONTROL SYSTEMS FLOW PATHS - OPERATING .' !

LIMITING CONDITION FOR OPERATION t

\

3.1.2.2 i be OPERABLE: At least two of the following three boron infection flow paths shall '

l

a. I The flow path from the beric acid tanks via a boric acid transfer I pump and a charging pump to the Reactor Coolant System.

b.

Two flow paths 4 from the refueling water storage tank via charging pumps to the Reactor Coolant System. ,

APPLICABILITY: MODES 1, 2, and 3.

l R16 ACTION:

l With only one of the above required baron injection flow paths to the Reactor

) Coolant System OPERABLE, restore at least two boron injection flow paths to the Reactor Coolant System to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in at least -

HOT STANDBY and borated to a SHUTDOWN MARGIN equivalent to at least 1% delta at 200*F within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months ; restore at least two flow paths to OPERABLE status within the next 7 days or be in HOT SHUTDOWN within the next 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

lR161

\ I -

SURVEILLANCE REQUIREMENTS 1!!!ilW 4.1.2.2 OPERABLE: At least3 two of the above recuired flow oaths shall be demonstrated

,,q p.e PMH h/ou ro W C 3* D "4 a.

At least once per 7 days by verifying that the temperature o the 50:t tr:: d ;;rti: . Of the f6 ;:th- from the boric acid tanks is

6. mser AAreater than or ecual to #42I- when it is a required water source.

3 tr. t east once per

'c, ays by verifying that each valve (manual, power operated or automatic) in the flow path that is not locked, sealed, or otherwise secured in position, is in its correct position. _

.s.

4 _At least once per 18 months during shutdown by verifying that each automatic valve in the flow path actuates to its correct position on a safety injection test signal. ,

-d--

At least once per 18 months by verifying that the flow p&th required e'

by Specification Coolant System. 3.1.2.2a delivers at least _~C (p- to the React JS GPM i

SEQUOYAH - UNIT 1 3/41-8 l Amendment No.12,157 i

March,30g 1992_

+s REACTIVITY CONTROL SYSTEMS f

,c BORATED WATER SOURCES - SHUTDOWN '

_ LIMITING CONDITION FOR OPERATION f 3.1.2.5 l OPERABLE: As a minimum, one of the'following borated water sources shall be i

a. !

A boric acid storage system and ::::inted '. :t tr::ing with: '

1. - s ooo A m.inimum contained borated water volume of 217; gallons,

) . Between 20 0 and 22,500 ppm of baron, and

3. A minimum solution temperature of 14: T. 6 J F. -- '

b. The refueling water storege tank with:

1.

A minimum contained borated water volume of 25,"4 gallons, t

2. !

A minimum boron concentration of 2500 ppm, and 6 3143 l

3. A minimum solution temperature of 60 F.

APPLICABILITY: MODES 5 and 6. i j

ACTION: %

W

}

With no borated water source OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes. !

SURVEILLANCE REOUIREMENTS ,

4.1.2.5 The above required borated water source shall be demonstrated OPERABLE:

a. At eas on per day by:

Wrd *d#

1. Ve fyi the ron c centr ion o the ter,

2. Ver' ying e ccn ined rate ater olum , and

3. erif 'ng the oric id st age nk so utio tem rat ,e w n it the s rce o borat wat .

/

wr stard ou 1

of ed r l

I i

1 I

l SEQUDYAH - UNIT 1 3/4 1-11 i

Amendment No. 140 MAY 111990 T n? e pr r --sqw ?

r u

REACTIVITY CONTROL SYSTEMS 1

A coamiamo vo m < of ,- i BORATED WATER SOURCES OPERATING Soru+rK o w m a. /d A * # D#

, ,a pox.c { ,

, 1. 2 . G, .

5 LIMITING CONDITION FOR OPERATION !

~

3.1.2.6 !

As a minimum, the following borated water source (s) shall be OPERABLE as required by Specification 3.1.2.2: '

a.

A boric acid storage system :nd :::::icted h::t tr :ing-with: $

1 j -ig_ @ d beged ger & ;f 717C ;;1' n;. 44

2. N- -. 7 :r- . I. N. . .^."*!',%. .r'~ . " " T. . . M, _ . . 'l

. y .

3. A minimum solution temperature of I?5oc 4,3 *F. l

b. The refueling water storage tank with:

1.

A contained borated water volume of between 370,000 and 375,000 gallons, !

{

2. Between 2500 and 2700 ppm of baron, i a144 i 3.

A minimum solution temperature of 60 F, and

4. A maximum solution temperature of 105 F.

l

! APPLICABILITY: MODES 1, 2, 3.:nd

g i

Awo $

ACTION:

t a.

With the boric acid storage system inoperable and being used as one I

'of 'the above required borated water sources, restore the storage system to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in at least HOT l

g7 STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and borated to a SHUTDOWN MARGIN '

equivalent to at least 1% delta k/k at 200 F; restore the boric acid storage system to OPERABLE status within the next 7 days or be in C L3 SHUTDOWN within the next 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

b.

With the refueling water storage tank inoperable, restore the tank l to OPERABLE status within one hour or be in at least HOT STANDBY l - 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 .

1 Amendment No. 140 SEQUDYAH - UNIT 1 3/4 1-12 t MAY 111990 I-yr - - - - - . , , . +m- , p .e,,., , - .

REACTIVITY CONTROL SYSTEMS

/

SURVEILLANCE REQUIREMENTS 4.1.2.6 Each borated water source shall be demonstrated OPERABLE:

g p[ At eas once er 7 days y:

(Jn79 ^#56"' O erif ng eb on nce rat' n i eac wate sour ,

(____#- . V ify'ig t co aine bor ed ter volu of ch w ser our , a. ,

' ri fy ' g t bor' a 'd s rag syst sol ion J mper ture when t is he urc of ora d wa r. / / ,

),cA.Aes lwere pseer.D g. A lejst onp4 per/24 pdurs/y v/ rifyirfg thytWSTfempeystur3/ /

~\s _,,,,

k i

l l

l I

i l

i SEQUOYAH - UNIT 1 3/4 1-13 l

l

BORIC ACID TANK REQUIRED VOLUME vs. BORIC ACID TANK CONCENTRATION 9,500 !

R ;

W \ l Z A \ ACCEPTABLE OPE RATION O

J g,gog ( {'\, ,x X o . ,

<f n 'N.\ \ !

o '

..s NA %

,x s N N 8'500

'A '$\- \

g 'css s.,sNN l w , % N N oc 4.A ' s. _ '%N -

O .

s\

.AN F '

.A 'a. s/N W g 909 .

W

, xs ., / x g 7s./ 's N

's..' 'A, 2

D

._ Wr.* .

'*y. / N,(~%

.,, N

s , N O 7,500 CONCENTRATION IN RWST: / /d' '>7%. \sld 2E 00 com // / /s. ~N %

E

) 2E 50 ohm // / /X \

'*v 2 2600 o'om/ // ~..\ .

D 2E 50 nom // s il 2 7,000 27 00'o'om/ N. w Z

2 ~6 120 ppm 89 90 ppm =

(Minirr um) (Maximum) 6,500 I 6,200 6,400 6,600 6,800 7,000 CONCENTRATION - ppm BORON FIGURE 3.1.2.6 SEQUOYAH - UNIT 1 3/4 1-13a

3/4.9 REFUELING OPERAIIONS 3/4.9.1 BORON CONCENTRATION 3

LIMITING CONDITION FOR OPERATION 3.9.1 With the reactor vessel head closure bolts less than fully tensioned or with the head removed >the boron concentration of all filled portions of the Reactor Coolant System and the refueling canal shall be maintained uniform and sufficient to ensure that the more restrictive of the following reactivity conditions is met:

Either a K *ff of 0.95 or less. which includes a 1% delta k/k -correr coasuarvc .

t

. se allowance for uncertainties, or

b. A boron concentration of greater than or equal to 2000 ppm, which includes a 50 ppm conservative allowance for uncertainties.

APPLICABILITY: MODE 6*

ACTION:

With the requirements of the above specification not satisfied, immediately U" N P'^

suspend all operations involving CORE ALTERATIONS or positive reactivity cnanges and initiate and continue boration at greater than or equal to 10 gp; ,,e/

of a solution containing greater than or equal to 20,02; ppm boron or its

. .. equivalent until Keff is reduced to less than or equal to 0.95 or the boron 612 0 ENGhn concentration is restored to greater than or equal to 2000 ppm, whichever is the more restrictive. The provisions of Specification 3.0.3 are not applicable.

SURVEILLANCE REQUIREMENTS 4.9.1.1 The more restrictive of the above two reactivity conditions shall be determined prior to:

a. Removing or unbolting the reactor vessel head, and

b. Withdrawal of any full length control rod in' excess of 3 feet from l its fully inserted position within the reactor pressure vessel.

R16 4.9.1.2 The boron concentration of the reactor coolant system and the refueling canal shall be determined by chemical analysis at least once per 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .

The reactor shall be maintained in MODE 6 whenever fuel is in the reactor l vessel with the vessel head closure bolts less than fully tensioned or with l the head removed.

R148 3/4 9-1 Amendment No. 12,144 SEQUOYAH - UNIT 1 August 1, 1990

i i

- i 3/4.10 SPECIAL TEST EXCEPTIONS i 3/4.10.1 SHUTDOWN MARGIN tIMITING CONDITION FOR OPERATION i

3.10.1 The SHUTDOWN MARGIN requirement of Specification 3.1.1.1 may be suspended !

f or rneasurement of control rod worth and shutdown margin provided reactivity ;

equivalent to at least the highest estimated control rod worth is available !

for trip insertion from OPERABLE control rod (s).

l i

APPLICABILITY: MODE 2. i ACTION: ;

i

s. With any full length control rod not fully inserted and with less than ;

the above reactivity equivalent available for trip insertion, immediately initiate and continue boration at greater than or equal to 10 ;; of a '

R16 solution containing greater than or equal to '0,000 en boron or i ,

l equivalent until the SHUTDOWN MARGIN requir by Specification 3.1.1.1 l 4fg , -.2 s restored. -

gy p

b. With all full length control rods inserted and the reactor subcritical by .

less than the above reactivity equivalent, ediately initiate and continue l

~ boration at creater than or equal to ?O ;; f a solution containing greater t

R16 !

than or equal 1 400.000 ; p boron or its equivalent until the SHUTDOWN l MARGIN required by Specification 3.1.1.1 is restored.

l i

TURVEILLANCE REQUIREMENTS 4.10.1.1 The positio:1 of each full length rod either partially or fully withdrawn shall be determined at least once per 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months .

4 10.1.2 Each full length rod not fully inserted shall be demonstrated capable of full insertion when tripped from at least 50% withdrawn position within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months prior to reducing the SHUTDOWN MARGIN to less than the limits of Specification 3.1.1.1.

MAR 251982 5EQUOYAH - UNIT 1 3/4 10-1 Amendment No. 12 i

I REACTIVITY CONTROL SYSTEMS BASES condition of all rods inserted (most positive MDC) to an all rods withdrawn

condition and, a conversion for the rate of change of moderator density with temperature at RATED THERMAL POWER conditions. This value of the MDC was then transformed into the limiting end of cycle life (EOL) MTC value. The 300 ppm surveillance limit MTC value represents a conservative value (with corrections R159 for burnup and soluble boron) at a core condition of 300 ppm equilibrium boron concentration and is obtained by making these corrections to the limiting E0L MTC value. R159 The surveillance requirements for measurement of the MTC at the beginning and near the end of each fuel cycle are adequate to confirm that the MTC remains within its limits since this coefficient changes slowly due principally ,

to the reduction in RCS boron concentration associated with fuel burnup.

I 3/4.1.1.4 MINIMUM TEMPERATURE FOR CRITICALITY l

t

This specification ensures that the reactor will not be made critical with the Reactor Coolant System average temperature less than 541*F. This limitation is required to ensure 1) the moderator temperature coefficient is within its analyzed temperature range, 2) the protective instrumentation is within its normal operating range, 3) the P-12 interlock is above its setpoint,

4) the pressurizer is capable of being in a OPERABLE status with a steam bubble,

('**"'

and 5) the reactor pressure vessel is above its minimum RT temperature.

NDT l 3/4.1.2 BORATION SYSTEMS ,

i The boron injection system ensures that ne tive reactivity control is ,

available during each mode of facility operation. The components required to l perform this function include 1) borated water'so rces, 2) charging pumps, 3) separate flow paths, 4) boric acid transfer pumps, 5) :::::i:ted h::t tracin;; i

y;ts;, cnd C an emergency power supply from OPERABLE diesel generators. I With the RCS average temperature above 350"F, a minimum of two separet and edundant berer infectier syster: 3re previded to ensure single fynctional ht161 capability in the event an assumed failure renders one of the cy:t :Finoperable.

The boration capability of either flow path is sufficient to provide a SHUTDOWN ]

MARGIN from expected operating conditions of 1.6% delta k/k after xenon decay and cooldown to 200'F. The maximum expected boration capability requirement occursatEOLfromfullpower-equi'ibri{xenonconditionsandrequires 4

7,, o ALo.J im mt er, e. u Flow ? Art +S N M*N

^ FLot-J Parr+s !

NEg PEAK SEQUOYAH - UNIT 1 B 3/4 1-2 Amendment No. 155, 157 March 30, 1992

l l

l REACTIVITY CONTROL SYSTEMS

)

BASES

& "30 50'2 gallen of 20,000 ppm borated water from-tAe boric acid :terage tank: or \

- S2,082 galkn: of 2500 ppr berated water from the refueling water storage tank. R144 )

> /usur#

With the RCS temperature below 350 F, one injection system is acceptable without single failure consideration on the basis of the stable reactivity lR161 l condition of the reactor and the additional restrictions prohibiting CORE ALTERATIONS and positive reactivity change in the event the single injection system becomes inoperable.

l 1

so*r ss2o The baron capability required o low 200 F, is sufficient to provide a /N N T~ #

SHUTDOWN MARGIN of 1% delta k/k afte xenon decay and coolde 140 F. This condition requires either-83G gallons of 20,00vp from 200 F to ppm borated water from the boric acid storage tanks or 0,000 gallons of 2500 ppm borated water R144 from the refueling water storage tank. (

The contained water volume limits include allowance for water not available j because of discharge line location and other physical characteristics. " /p$4 r Gr

%v The limits on contained water volume and boron concentration of the RWST also ensure a pH value of between 7.5 and 9.5 for the solution recirculated within containment after a LOCA. This pH band minimizes the evolution of iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.

The OPERABILITY of one boron injection system during REFUELING ensures that this system is available for reactivity control while in MODE 6.

3/4.1.3 MOVABLE CONTROL ASSEMBLIES I

l The specifications of this section ensure that (1) acceptable power distri- ;

bution limits are maintained, (2) the minimum SHUTDOWN MARGIN is maintained, '

and (3) limit the potential effects of rod misalignment on associated accident analyses. OPERABILITY of the control rod position indicators is required to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits.

SEQUOYAH - UNIT 1 B 3/4 1-3 Amendment No. 140 157 March 30, 1992 1

. _-. ~ . - _. _ _ _ _ . _ . _ _ ___ _ _ . . _ _ _ _ _ _ _ - - ._,

4 i )

i :

} l

! i

'. x 3/4.1 REACTIVITY CONTROL SYSTEMS !

3 ,

j 3/4.1.1 BORATION CONTROL !

1 i SHUTDOWN MARGIN - T, >200*F i !

4 LIMITING CONDITION FOR OPERATION

( - t e .

j 3.1.1.1 The SHUTDOWN MARGIN shall be greater than or equal to 1.6% delta k/k l l

for 4 loop operation.

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

ACTION: yg qpn )

.With the SHUTDOWN MARGIN less than 1.6% delta k/k, immediately. initiate and j continue boration at greater than or equal to _0 ;p of a solution containing ,

4 greater than or equal to 20,000 ;;r boron or equivalent until the required SHUTDOWN MARGIN is restored.

dizo F M l i

. SURVEILLANCE REOUIREMENTS i

4.1.1.1.1 The SHUTDOWN MARGIN shall be determined to be greater than or equal >

to 1.5% delta k/k: s i

f f

a. Within one hour after detection of an inoperable control rod (s) and '!

at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter while the rod (s) is. inoperable. ;

If the inoperable control rod is immovable or untrippable, the above !

required SHUTDOWN MARGIN shall be verified acceptable with an increased allowance for the withdrawn worth of the immovable or untrippable i control rod (s).

b, When in MODE 1 or MODE 2 with K greater than or equal to 1.0, at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by verihng that control bank withdrawal is within the limits of Specification 3.1.3.6.

c. When in MODE 2, with K less than 1.0, within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months prior to achieving reactor critTNlity by verifying that the predicted critical control rod position is within the limits of Specification 3.1.3.6.

d. Prior to initial operation above 5% RATED THERMAL POWER after each fuel loading, by consideration of the factors of e below, with the control banks at the maximum insertion limit of Specification 3.1.3.6.

~

1

^5ee Special. Test Exception 3.10.1 SEQUOYAH - UNIT 2 3/4 1-1 l

...-i

REACTIVITY CONTROL SYSTEMS avg < 200 F SHUTDOWN MARGIN - T LIMITING CONDITION FOR OPERATION 3.1.1.2 The SHUTDOWN MARGIN shall be greater than or equal to 1.0% delta k/k.

APPLICABILITY: MODE 5.

ACTION: 3fgpg With the SHUTDOWN MARGIN less than 1.0% delta ,k/k, immediately initiate and continue boration at greater than or equal to h 10 gp: of a solution containing greater than or equal to :,CCO pp: boron or equivalent until the required SHUTDOWN MARGIN is restored.

Ctr o pp SURVEILLANCE REOUIREMENTS 4.1.1.2 The SHUTDOWN MARGIN shall be determined to be greater than or equal ,

to 1.0% delta k/k: l

a. Within one hour af ter detection of an inoperable control rod (s) and at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter while the rod (s) is inoperable.

If the inoperable control rod is immovable or untrippable, the SHUTDOWN MARGIN shall be verified acceptable with an increased allowance for the withdrawn worth of the immovable or untrippable control roc (s),

b. At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by consideration of the following factors:

1. Reactor coolant system boron concentration, l

2. Control rod position,

3. Reactor coolant system average temperature, 4 Fuel burnup based on gross thermal energy generation, S. Xenon concentration, and

6. Samarium concentration.

SEQUOYAH - UNIT 2 3/4 1-3 l 1

1 i

REACTIVITY CONTROL SYSTEMS l

3/4.1.2 BORATION SYSTEMS FLOW PATH - SHUTDOWN l i LIMITING CONDITION FOR OPERATION l

l 1

l 3.1.2.1 As a m nimum, one of the following boron injection flow paths shall ;

i be OPERABLE:

l a. A flow path from the boric acid tanks via a boric acid transfer pump l and a charging pump,to the Reactor. Coolant System if the boric acid storage tank in Specification 3.1.2.5a is OPERABLE, or

b. The flow path from the refueling water storage tank via a charging !

pump to the Reactor Coolant System if the refueling water storage tank in Specification 3.1.2.5b is OPERABLE.

APPLICABILITY: MODES 4, 5 and 6.

ACTION: i R147 i MODE 4 - With none of the above flow paths OPERABLE, suspend all operations ;

involving CORE ALTERATIONS or positive reactivity changes and restore

(. ..

one flow path as soon as possible.

i W

j MODES 5 - With none of the above flow paths OPERABLE, suspend all operations l and 6 involving CORE- ALTERATIONS or positive reactivity changes.

1 l

SURVEILLANCE REQUIREMENTS l

4.1.2.1 At t one of the above required flow OPERABLE: A ss courmmm, >=co w Mrs coaowur:, F4cm ThC S o.listrate c Aci o PAN K O e Wo va Acao,aq TEE

a. At least once per 7 days by verifying that the temperature of the ' - - -

6,3

h;;t IT 0^d p;rtion of the flew p:th is greater than or equal to 44694 when : #1 e p:th fre- the beri ::id t:nk: i: u::d.

6. ~1n iu+ A * --

t least once per 31 days by verifying that each valve (manual, power operated or automatic) in the flow path that is not locked, q sealed, or otherwise secured in position, is in its correct position.

ir is M #4Qw/aso u W Stsaac<.

I, 1

l SEQUOYAH - UNIT 2 3/4 1-7 Amendment No.147 March 30, 1992-

REACTIVITY CONTROL SYSTEMS FLOW PATHS - OPERATING I LIMITING CONDITION FOR OPERATION i

3.1.2.2 At least two of the following three boron injection flow paths shall I be, OPERABLE:

a. The flow path from the boric acid tanks via a boric acid transfer -

pump and a charging pump to the Reactor. Coolant System. ;

b. Two flow paths. from the refueling water storage tank via - charging !

pumps to the Reactor Coolant System. ;

APPLICABILITY: Modes 1, 2, and 3. R147 !

ACTION: !

l With only one of the above required baron injection flow paths to the Reactor :

Coolant System OPERABLE, restore at least two boron injection flow paths to i i

the Reactor Coolant System to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in at i

least HOT STANDBY and borated to a SHUTDOWN MARGIN equivalent to at least 1% -

I delta k/k at 200*F witnin the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months ; restore at least two flow paths to I l OPERABLE status within the next 7 days or be in HOT SHUTDOWN within the next ' l 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months . l R147 '

SURVEILLANCE REOUIREMENTS t

hmW I

4.1.2.2 At least two of the above recuired flow paths shall be demonstrated j

OPERABLE:

A4tAs b r we,v/^i G F 4o w PMrs C o.4.,e a u ,

" WE'M .

'%

l ;

a. At least once per cays by veritying tnat the temperature of the -

%:t tr:::d ;:rtion :f the fi:w ;;th from the boric acid tanks is l greater than or ecual to IC when it is a required water source. -

l h, msser 4 OE

-b- At least once per 31 days by verifying that eacn valve (manual, l power operated or automatic) in the flow path that is not locked, l l sealed, or otherwise secured in position, is in its correct position. !

-e- At least once per 18 months during shutdown by verifying that each c), automatic valve in the flow path actuates to its correct position on a safety injection test signal.

4 At least once per 18 months by verifying that the flow path required

6. by Specification 3.1.2.2a delivers at least 10 ;p to the Reactor Coolant System.

35 Gym i

I l

! SEQUOYAH - UNIT 2 3/4 1-8 Amendment No.147 Mar::h 30,1992

REACTIVITY CONTROL SYSTEMS !

t

[ BORATED WATER SOURCE - SHUTDOWN ;

I LIMITING CONDITION FOR OPERATION I i

3.1.2.5 As a minimum, one of the following borated water sources shall be :

OPERABLE:

-l

\

a. A boric acid storage system and at len t enc :: ciated he:t tr cing i y:te: with:

A minimum contained borated water volume of 4N& gallons,

(, 2.o A@ 6170 l

. Between 20,000 and 22,500 ppm of boron, and

3. A minimum solution temperature of 145

b. The refueling water storage tank with:

1. A minimum contained borated water volume'of 35,443 gallons, j

2. A minimum boron concentration of 2500 ppm, and R13 i l 3. A minimum solution temperature of 60 F. :

V APPLICABILITY: MODES 5 and 6. !

ACTION: 4; j i

With no borated water source OPERABLE,' suspend all operations involving CORE I ALTERATIONS or positive reactivity changes.

SURVEILLANCE REQUIREMENTS f

4.1.2.5 The above required borated water source shall be demonstrated OPERABLE:

jr(

4 gg virn guer B At as nc er days y:

. eri ing ie b on co entrj ion o the er, j l

rify' g t cont 'ned rated ater lum and l 3. Ver' yin the b ic a d sto ge ta

~

so tion emp atur wh

! is e so ce of orate water /

l v i~ r C- ou f t r l

(

j SEQUOYAH - UNIT 2 3/4 1-11 Amendment No. 131 00T 29 bd I

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

. .- - . . . . . = _ . .-. .

l REACTIVITY CONTROL SYSTEMS p w r74'N & V"'"*" W '

BORATED WATER SOURCES - OPERATING g,ea rgo wru in ho ewA~d { ;

w m4 PI G u d G- 3. l . ?- .

LIMITING CONDITION FOR OPERATION l 3.1.2.6 As a minimum, the following borated water source (s) shall be OPERABLE !

as required by Specification 3.1.2.2: )

i

a. A boric acid storage system and at 'c :t One :::cciated 5 :t traci q '

cytte with:

a _: :_,._ -- +,:- a a L---+ m,+,.--1..-- a 71 rc -,11--- R13:

2. 2;umm=;nm.,5;;;;m.;.4> .

h tecer 20,000 :nd T 00 ppr cf beren, 2n h - - ;

3. A minimum solution temperature of 145 r 4 F

F. ,

b. The refueling water storage tank with:

1

1. A contained borated water volume of between 370,000 and 375,000 gallons,

2. Between 2500 and 2700 ppm of boron, and R13:

3. A minimum solution temperature of 60 F. M I

4. A maximum solution temperature of 105 F.

1 APPLICABILITY: Modes 1, 2, 3,and 1 I ACTION:

a. With the boric acid storage system inoperable and being used as one of the above required borated water sources, restore the storage system to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months 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 borated to a SHUTDOWN MARGIN.

equivalent to at least 1% delta k/k at 200*F; restore the boric acid i storage system to OPERABLE status within the next 7 days or be in I N SHUTDOWN within the next 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

b. With the refueling water storage tank inoperable, restore the tank ~

to OPERABLE status within one hour or be in at least H0T 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 .

i l

l l'

i i

l 1

SEQUOYAH - UNIT 2 3/4 1-12 Amendment No. 131 1

l l.

007i; C0 l

.,- l

REACTIVITY CONTROL SYSTEMS SURVEILLANCE REQUIREMENTS 4.1. 2. 6 Each borated water source shall be demonstrated OPERABLE:

gp t le st o ep 7d'[sby-N # * '# 1. Ve fyi the oron conc ntra on 'n th wate ,

2. /eri ying e cc tai d bo ted water volu, of he ter so ce, d t.e bo ca ds rage yste sol ion erifing/the empeatue/

84a m / whe it i ourt of orate wat

.m wsurD _.

p. /nt legst onp4 pe/24 nybrs fy ver}fying/the y%ST t/mpergturg. / l t

U 1

( SEQUOYAH - UNIT 2 3/4 1-13 i

l_--_____---_-.-_

l BORIC ACID TANK REQUIRED VOLUME 1 vs. BORIC ACID TANK CONCENTRATION 9,500 R

! (D \

Z A . \ ACCEPTABLE OPE RATION i 4 b 9,000 c [\,\ ,x l m

( A '\.\ \, l O ".h \\ \

cs s ys, x

' 'A

8'500 S\- \

1 g 'Js " sf's N l w ' s, % 4 .N N .

oc 4. A 'v 's s A i O -

s fs.

.AN l

H '

'- A @- \l\

(D 8 000 '

, xs ., / N g W 's . A, rs/ '% N 2 '*,,'7sT m

sN i

D "'V. /N,(~% ,,, N O 7,500 CONCENTRATION IN RWST: / /I' ~>7 %. \s.l l

) 2E00 nom // / /s. ~N . % 1 2E 50 oom // / /1 'N N 2 26 00 ' 'oon/ // ' ' . . 's' D 26 50 nom // s .

1 2 7,000 27 00'obm/

Z N.*I I I 2 ~6 120 com '

89 90 nom =

(Minirr um) (Maxirimm)

~

6,500 6,200 6,400 6,600 6,800 7,000 CONCENTRATION - ppm BORON FIGURE 3.1.2.6 SEQUOYAH - UNIT 2 3/4 1-13a

i

( 3/4.9 REFUELING OPERATIONS l

! 3/4.9.1 BORON CONCENTRATION l LIMITING CONDITION FOR OPERATION 3.9.1 With the reactor vessel head closure bolts less than fully tensioned or l with the head removed, the boron concentration of all filled portions of the i Reactor Coolant System and the refueling canal'shall be maintained uniform and !

sufficient to ensure that the more restrictive of the following reactivity conditions is met-I

a. of 0.95 or less, which includes a 1% delta k/k I EitheraK@allowanceforuncertainties,or conservati l

b. A baron concentration of greater than or equal to 2000 ppm, which !

includes a 50 ppm conservative allowance for uncertainties. 1 APPLICABILITY: MODE 6*

ACTION: l 3f Gem j With the requirements of the above specification not satisfied, immediately suspend all operations involving CORE ALTERATION or positive reactivit changes and initiate and continue boration at gre ater than or equal to- 10 ;;;m of a solution containing greater than or equal teFGO-000 ppm boron or its equivalent until K is reduced to less than or equal to 0.95 or the boron concentration is r$Nored to greater than or equal to 2000 ppm, whichever is the more restrictive. The provisions of Specification 3.0.3 are not applicable.

SURVEILLANCE RE0VIREMENTS '

l 4.9.1.1 The more restrictive of the above two reactivity conditions shall be determined prior to:

a. Removing or unbolting the reactor vessel head, and

b. Withdrawal of any full length control rod in excess of 3 feet from its fully inserted position within the reactor pressure vessel.

^ The reactor st.all be maintained in MODE 6 whenever fuel is in the reactor vessel with the vessel head closure bolts less than fully tensioned or with R104 the head removed.

SEQUOYAH - UNIT 2 3/4 9-1 Amendment No. 104 May 5, 1989

l i

l

)

t 3/4.10 SPECIAL TEST EXCEPTIONS .!'

3/4.10.1 SHUTDOWN MARGIN !

i; LIMITING CONDITION FOR OPERATION l l

t 3.10.1 The SHUTDOWN MARGIN requirement of Specification 3.1.1.1 may be suspended ;

for measurement of control rod worth and shutdown margin provided reactivity equivalent to at least the high2st estimated control rod worth is available for trip insertion from OPERABLE control rod (s). !

APPLICABILITY: MODE 2. i ACTION: I t

a. With any full length control rod not fully inserted and with less than f the above reactivity equivalent available for trip insertion immediately !

initiate and con +inue boration at greater than or equal to-10 ;r- of a solution containing greater than or equal toKO.000 pe;. boren or its i i

equivalentuntiltheSHUTDOWN. MARGIN [requiredbySpecification3.1.1.1 is restored. l gg,,, ,3 (3fgpgg

b. With all full length control rods fully nserted and the reactor (

- subtritical by less than the above react vity equivalent, immediately f 1'

i initiate and continue boration at greater than or equal to 10 spr of a .

solution containing greater than or equal to. 0.000 ;;; boron or its j equivalent until the SHUTDOWN MARGIN required by Specification 3.1.1.1 is restored. ,

SURVEILLANCE REOUIREMENTS c

4.10.1.1 !

The position of each. full length rod either partially or fully I withdrawn shall be determined at least once per 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months . '

4.10.1.2 Each full length rod not fully inserted shall be demonstrated capable !

of full insertion when tripped from at least the 50% withdrawn position within !

24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months prior to reducing the SHUTDOWN MARGIN to less than the limits of Specification 3.1.1.1. l 1

l 1

l l

l SEQUOYAH - UNIT 2 3/4 10-1

REACTIVITY CONTROL SYSTEMS BASES 3/4.1.1.3 MODERATOR TEMPERATURE COEFFICIENT (Continued) involved subtracting the incremental change in the MDC associated with a core condition of all rods inserted (most positive MDC) to an all rods withdrawn -

condition and, a conversion for the rate of change of moderator density with temperature at RATED THERMAL POWER conditions. This value of the MDC was then ;

transformed into the limiting end of cycle life (EOL) MTC value. The 300 PPM R146 .

surveillance limit MTC value represents a conservative value (with corrections ,

for burnup and soluble boron) at a core condition of 300 ppm equilibrium boron !

concentration and is obtained by making these corrections to the limiting EOL R146 i MTC valu2.

The surveillance requirements for measurement of the MTC at the beginning i and near the end of the fuel cycle are adequate to confirm that the MTC remains ;

within 1ts limits since this coefficient changes slowly due principally to the reduction in RCS boron concentration associated with fuel burnup.

3/4.1.1.4 MINIMUM TEMPERATURE FOR CRITICALITY This specification ensures that the reactor will not be made critical ;

with the Reactor Coolant System average temperature less than 541*F. This hsd l limitation is required to ensure 1) the moderator temperature coefficient is l within it analyzed temperature range, 2) the protective instrumentation is i within its normal operating range, 3) the P-12 interlock is above its setpoint, I i

4) the pressurizer is capable of being in a OPERABLE status with a steam l bubble, and 5) the reactor pressure vessel is above its minimum RT temperature. NDT 3/4.1.2 BORATION SYSTEMS g

The boron injection system ensures that ne tive reactivity control is available during each mode of facility operation. The components required to perform this function include 1) borated water so rces, 2) charging pumps, 3) !

' separate flow paths, 4) boric acid transfer pumps,'IS) 2 :::icted 50:t tr :ing systems, and 5) an emergency power supply from OPERABLE diesel generators.

With the RCS average temperature above 350'F, a min'imum of two ::per;t: gia7 ead eedu-diat berer 4"jectier :y:ter cr provided to ensure single functional capability in the event an assumed failure renders one of the flow paths inoperable. The boration capability of either flow path is sufficient to

- A-y ,a ,agmon Ft.oa Wns AM M*MD SEQUOYAH - UNIT 2 B 3/4 1-2 Amendment No. 147, 146 i

March 30, 1992

REACTIVITY CONTROL SYSTEMS i

4 BASES I

B0 RATION SYSTEMS (Continued) NcM. gj.g l 1

provide a SHUTDOWN MARGIN from expected operating conditio of 1.6% delta k/k after xenon decay and cooldown o 200 F. The maximum ex cted boration j capability requirement occurs at EOL from full power e';ei-i= xenon '

l conditions and requires 50".' g lh .; -f 20,000 pp.. borated water from-%e- i

--+-"^-"^""^~^# * ^ - ' - " " ^ - ' - - - ' ' - '

R131 boric acid '+ 35E5-S t e ^ 'e W; ,

With the RCS temperature below 350 F, one injection system is acceptable lR147 ;

, without single failure consideration on the basis of the stable reactivity condition of the reactor and the additional restrictions prohibiting CORE e

! ALTERATIONS and positive reactivity changes in the event the single injection system becomes inoperable. 3 coo The boron capability required be w-200'F-is sufficient ti provide a war F SHUTDOWN MARGIN of 1% delta k/k after non decay and cooldow from 200 F to i 140*F. This condition requires either gallons of 20,000 ppm borated water from the boric acid storage tanks or gallons of 2500 ppm borated water R131 from the refueling water storage tank. 13,4 ;

l ( The contained water volume limits include allowance for water not '

W available because of discharge _line cation and other physical characteristics. -

w s e r- 4 l l \

' The limits on contained water volume and boron concentration of the RWST 3R l also ensure a pH value of between 7.5 and 9.5 for the solution recirculated !

within containment after a LOCA. This pH band minimizes the evolution of '

iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.

l The OPERABILITY of one boron injection system during REFUELING ensures that this system is available for reactivity control while in MODE 6.

3/4.1.3 MOVABLE CONTROL ASSEMBLIES The specifications of this section ensure that (1) acceptable power j distribution limits are maintained, (2) the minimum SHUTDOWN MARGIN is main- '

tained, and (3) limit the potential effects of rod misalignment on associated accident analyses. OPERABILITY of the control rod position indicators is required to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits.

f i

SEQUDYAH - UNIT 2 B 3/4 1-3 Amendment No. 131 !

147 March 30,1992 i 1

i

?nsert A i

Whenever the area temperature (s) is(are) less than 63*F and the boric !

acid tank is aLrequired water source, the solution temperature in'the !

flow path components from the boric acid tank must be measured to be (

greater than'or equal to 63*F with3n 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and every 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months ;

thereafter until the area temperature (s) has(have) returned to greater l than or equal to 63*F. l

-l.

[

Insert B ;

I

a. For the boric acid storage system, when it is the source of borated h water by:

1. Verifying the boron concentration at least once per 7 days, j

2. Verifying the borated water volume at least once per 7 days, and

3. Verifying the boric acid tank solution temperature is greater?

than or equal to 63*F at least once per 7 days by verifying the l

area temperature to be greater than.or equal to 63*F, or ;

)

4. Whenever the boric acid tank area temperature is less than 63*F l and the boric acid storage system being used as the source of ;

borated water, within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and every 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter, !

verify the boric acid tank solution temperature to be greater !

than or equal to 63*F until the boric acid tank area temperature !

has. returned to greater than or equal to 63*F. I

! I Insert C l

b. For the refueling water storage tank by:

l

1. Verifying the boron concentration at least once per 7 days, {

i

2. Verifying the borated water volume at least once per 7 days, and l

3. Verifying the solution temperature at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months {

while in Mode 4 or while in Modes 5 or 6 when it'is the source of I borated water. i l

l1 Insert D

b. For the refueling water storage tank by:

1. Verifying the boron concentration at least once per 7 days, ;

2. Verifying the borated water volume at least once per 7 days, and

3. Verifying the solution temperature at least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

lnaert E tank in accordance with TS Figure 3.1.2.6. and additional makeup _from either: (1) the common boric acid tank and/or batching, _ or (2) a minimum of 26,000 gallons of 2500 ppm borated water from the refueling water storage tank. With the refueling water storage tank as the only borated water source, a. minimum of 57,000 gallons of 2500 ppm borated water is required.

Insert F SHUIDOWN MARGIN of 1.6% delta k/k after xenon decay and cooldown from 350*F to 200*F, and a Insert G The 55,000 gallon limit in the refueling water storage tank for Modes 4, 5, and 6 is based upon 22,182 gallons that is undetectable due .to lower tap location, 19,197 gallons for instrument error, 13,400 gallons required for shutdown margin, and an additional 221 gallons due to rounding up.

Insert H The boric acid tanks, pumps, valves, and piping _contain-a boric acid solution concentration of between 3.5% and 4.0% by. weight. To ensure that the boric acid remains in solution, the air temperature is monitored in strategic locations. By ensuring the air temperature remains at 63*F or above, a 5'F margin is provided to ensure the boron will not precipitate out. To provide operational flexibility, if.the area temperature should fall below the required value, the solution temperature (as determined by the pipe or tank wall temperature) will be monitored at an increased frequency to compensate for the lack of solution temperature alarm in the main control room.

i 4

ENCLOSURE 2 ,

PROPOSED TECHNICAL SPECIFICATION CHANGE SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 f (IVA-SQN-TS-92-08)

DESCRIPTION AND JUSTIFICATION FOR BORIC ACID CONCENTRATION REDUCTION i I

1 l

l l

l Mentription of Change !

i TVA proposes to modify the Sequoyah Nuclear Plant (SQN) Units 1 and 2 l technical specifications (TSs) to allow the boric acid concentration'in the boric acid tanks (BATS) to be reduced from 12 percent to 1 approximately 3.5 to 4.0 percent by weight. The BATS are a part of the 'l chemical and volume control system that is described in the Updated Final !

Safety Analysis Report (UFSAR) Section 9.3.4 and Figures 9.3.4-1, j 9.3.4-2, and 9.3.4-5. UFSAR changes will be required as a result of the l proposed change. The following paragraphs provide a brief description of each change as it applies to Unit 1. Unit 2 will be similar.

TS 3.1.1.1 action statement (page 3/4 1) will be revised to increase

'l the flow rate from 10 gallons per minute (gpm) to 35 gpm and to decrease-the boron concentration from 20,000 parts per million (ppm) to greater than or equal to 6,120 ppm.

TS 3.1.1.2 action statement (page 3/4 1-3) will be revised to increase l the flow rate from 10 gpm to 35 gpm and decrease the boron concentration ;

from 20,000-ppm boron to 6.120-ppm boron. l t

TS 3.1.2.1 Surveillance Requirement (SR) 4.1.2.1 (page 3/4 1-7) will be l revised to replace the discussion pertaining to the heat tracing and l required heat trace temperature with the required ambient temperature parameters. Increased SRs_for solution monitoring when the area j temperature falls below the stated 63 degrees Fahrenheit (F) are added as ,

Item b, requiring the existing SR Item b to be relabeled Item c.

TS 3.1.2.2 SR 4.1.2.2 (page 3/4 1-8) will be revised to reference the .

required minimum ambient room temperature for the boric acid flow path I components and delete the heat trace requirements. Similar SRs will be :

added as described above. SR ltems b, c, and d are relabeled. t TS 3.1.2.2 SR 4.1.2.2.d (page 3/4 1-8) will be revised to increase the }

flow rate from 10 gpm to 35 gpm. j I

TS 3.1.2.5.a (page 3/4.1-11) will be revised to delete the heat-trace ;

requirement. Part I will have the required boric acid solution volume increased to 5,000 gallons. The concentration in Part 2 has been reduced l to between 6,120 ppm and 6,990 ppm of boron, which correlates to i approximately 3.5 ~ to 4.0 percent by weight. Part 3 will now require the :

temperature of the solution in the boric acid tanks to_be maintained at I 63 degrees F instead of'145 degrees F. Additionally, the mode of l applicability has been expanded to include Mode 4. i j

TS 3.1.2.5.b (page 3/4 1-11) will be revised to increase the required boric acid solution volume in the refueling water storage tank (RWST)

from 35,443 gallons to 55,000 gallons.

l TS 3.1.2.5 SR 4.1.2.5 (page 3/4 1-11) will be revised to require the area temperature to be verified to be greater than or equal to 63 degrees F.

A conditional surveillance has been added as Item 4.1.2.5.a.4 to verify solution temperature when the; area temperature falls below the specified 63 degrees F. Additionally, the format of the surveillance' statement will be revised to separate the boric acid storage system (labeled a) and the RWST (labeled b) requirements.

t I

l i

I l

TS 3.1.2.6 (page 3/4 1-12) will be revised to delete the heat trace requirement and indicate the required volume and concentration of boric acid in the boric acid storage system. Figure 3.1.2.6 has been added to provide the variable relation between concentration and volume. The solution temperature of 145 degrees F has been reduced to 63 degrees F. ;

Mode 4 has been deleted as an operational mode of applicability.

TS 3.1.2.6 Action Statement a (page 3/4 1-12) will change the reference !

from COLD shutdown to HOT shutdown.

TS 3.1.2.6 SR 4.1.2.6 (page 3/4 1-13) will be revised similar to SR 4.1.2.5.

TS 3.9.1 action statement (page 3/4 9-1) will be revised to increase the flow rate from 10 gpm to 35 gpm and to decrease the boron concentration from 20,000-ppm boron to 6,120-ppm boron. For Unit 1 only, two typographical errors have been corrected.

TS 3.10.1 Action Statements a and b (page 3/410-1) will be revised to increase the flow rate from 10 gpm to 35 gpm and to decrease the boron concentration from 20,000-ppm boron to 6,120-ppm boron.

The bases for the boration system (pages B 3/4 1-2 and 1-3) will be revised to delete the reference to the heat trace system. Additionally,

, the volumes and concentrations of borated water have been changed to l reflect the calculations performed in Enclosure 4 that support the boron l concentration reduction proposed in this change. As an additional point.

l the previous reference to end-of-life (EOL) equilibrium xenon has been I changed to near EOL peak xenon. New statements have been added to describe the room temperature monitoring and the RWST shutdown margin volume requirements.

Reason for Change The original design of SQN required the boron concentration in the BATS to be approximately 12 percent by weight. This concentration presently creates two major operational problems. First, the leakage from the chemical and volume control system (CVCS) presents a corrosion problem that can cause pump seal failures, valve failures, and fitting leaks.

Second, the heat tracing requirements for the CVCS are extensive and-

! require significant maintenance to maintain them operable. If a heat

trace failure is undetected, the possibility of pipe blockage because of l boric acid precipitation may render one of the flow paths inoperable, ;

impacting safety system availability. By reducing the concentration to l between 3.5 and 4.0 percent by weight and maintaining the appropriate temperature in the immediate area to at least 63 degrees F, the previously listed problems are eliminated. Based upon the changes in the I required volumes, concentrations, and solution temperature, the associated SRs were changed to include the new parameters to be l monitored. For additional clarification, the format was revised.

i 1

I l

I

Since Westinghouse Electric Corporation provides the reload analysis for each fuel cycle, they were requested to review this change to identify interface problems that would prevent them from performing their analysis. During that review, Westinghouse identified that the maximum boration requirements occur at near EOL peak xenon and not EOL equilibrium conditions. Based upon this recent review, the bases are being revised to reflect this change.

The borated water volume required in the RWST for Modes 4, 5, and 6 has been increased to 55,000 gallons to provide for the new boration requirements to maintain shutdown margins and additional instrument inaccuracies.

The movement of Mode 4 applicability from TS 3.1.2.6 to TS 3.1.2.5 was made to provide agreement with the boration flow path TS requirements.

This change also requires that the reference to COLD shutdown be changed to HOT shutdown in the action statement in TS 3.1.2.6.

Justifica11rn for Change The boric acid storage system borated water volume and boron concentration minimum values presently specified in the SQN TS are based upon the ability to borate the reactor coolant system (RCS) to the required cold shutdown boron concentration via a feed and bleed process.

The present method used to achieve cold shutdown is to borate the RCS to ,

the required concentration to obtain the TS shutdown margin of 1 percent l delta k/k at 200 degrees F before starting the plant cooldown. The CVCS is then required to provide adequate makeup of sufficiently borated water to compeneate for shrinkage as the RCS temperature is lowered to cold shutdown.

The proposed boric acid concentration reduction in the BATS will be accomplished by making a change to the plant boration and cooldown procedures. Enclosure 4 reevaluates the original requirements for the i BAT boric acid concentration to show the acceptability of the new i methodology of boration-to-cold shutdown with the reduced boron '

concentration. The new method of boration-to-cold shutdown requires that the boron concentration for a given temperature of the RCS be provided during the cooldown to ensure the proper shutdown margin is maintained.

When cooldown is started, makeup from the BAT is provided until such time as its original volume is depleted. At this time, additional volume from the common BAT, or from batching operations, or from the RWST is provided because of the volume limitations of a single BAT. The above combination or the RWST alone provides an adequate supply of borated water to ensure j the required shutdown margin is maintained. Based upon the review of l Enclosure 4, it has been determined that the bounding scenario (and I licensing basis) for defining the shutdown margin boration requirements is now considered to be near EOL peak xenon. Therefore, this clarification to the basis has been provided.

! I f ,

I j To operate at the proposed lower boric acid concentrations, the minimum .

i required volume delivery rate will be increased to 35 gpm to ensure that .

i the same net weight of boron will be supplied as required by the current j TS. SQN will be modifying the CVCS, which will include a piping change ;

to the boric acid blender to allow for the higher-required flow rate and the recalibration of the BAT level transmitter to allow for the maximum i utilization of the BAT volume. Additionally, the heat trace system will ;

be deenergized. ,

The volume of borated water required to provide adequate shutdown margin !

for Modes 4 through 6 (i.e., RCS less than 350 degrees F) is l 13,400 gallons from the RWST. . Enclosure 4 provides calculations to l support this new volume requirement. The proposed TS requires 55,000 gallons. This quantity was derived from a combination of: l (1) the location of the lower tap for the level transmitters on the RWST, !

(2) cdditional instrument inaccuracies, (3) conservatism to. provide for

[

gauge legibility in the control room, and (4) 13,400 gallons provided for i shutdown margin. ;

i Mode 4 applicability has been removed from TS 3.1.2.6 and added to i TS 3.1.2.5 to provide for operational agreement with TSs 3.1.2.1 and i 3.1.2.2. By providing the agreement, the required borated water source !

will be aligned with the appropriate path. The bases have been revised l to indicate the required boron concentration for above and below -

350 degrees F. For both cases there is an adequate supply of borated !

water to provide the required shutdown margins. Enclosure 4 provides the calculations that address the use of the boric acid tank or the RWST to ;

bring the unit from 350 degrees F to 135 degrees F and still provide j adequate shutdown margin. j When performing batching operations, the boric acid batching tank is l heated well above 63 degrees F to ensure the boric acid will enter into ;

solution easily. This will ensure that when the boric acid solution is i transferred to the BAT, it is at an elevated temperature relative to the l area ambient temperature. The 63 degrees F area temperature was selected '

to provide sufficient margin to ent:ure the boric' acid will remain in solution. It has been shown by analysis that a 3.5 percent weight solution of boric acid will remain dissolved at a solution temperatute of approximately 50' degrees F. For the " worst-case" condition when there is a 4.0 percent solution, the boron still will not precipitate out until the temperature falls below 58 degrees F. The margin established of approximately 5 to 13 degrees F'is considered sufficient since the BAT and CVCS piping are housed in areas that are normally above the 63 degrees F minimum. ;

I UFSAR Section 9.4.2.2.1 describes the capabilities of the auxiliary building ventilation system. Based upon an expected range of external temperatures, the system is capable of maintaining the building temperature from 60 degrees F to 85 degrees F. On rare occasions there

~

is the possibility that air temperatures in the auxiliary building may drop to approximately 60 degrees F. As a part of the modification, continuous temperature monitoring of the areas containing boration flow paths and components will.be provided with an alarm in the control room to annunciate whenever the area temperature drops below 63 degrees F.

This alarm will be used to initiate' additional monitoring to ensure that- j the solution temperature remains at or above the 63 degrees F requirement. l

Enclosure 4 was submitted to the SQN steam supply system vendor (Westinghouse) for review. Westinghouse reviewed the document for:

(1) functional consistency with the original CVCS design (and interfacing auxiliary fluid systems designed by Westinghouse), (2) impact on the loss-of-coolant accident (LOCA) and non-LOCA transient analyses performed ,

by Westinghouse and included in Chapter 15 of the Final Safety Analysis I Report, and (3) effect on the core reload safety analysis process j performcd by Westinghouse. Based upon that review, Westinghouse '

concluded that the new boration methodology can be integrated with the interfacing Westinghouse system functional requirements and analysis of record. Integration with Westinghouse design requirements and analytical i conclusions will ensure these documents remain correct and bounding.

By revising the format of SRs 4.1.2.5 and 4.1.2.6, the actual SRs were $

not changed (except for those proposed by this submittal), but were aligned with the TS requirements and action statements. This change will l eliminate any confusion that was introduced in the original format. :

TVA has performed an additional review to assess the impact this change l has upon the SQN 10 CFR 50 Appendix R requirements. As previously i discussed, the new shutdown methodology presented in Enclosure 4 requires I a change from boration prior to plant cooldown to during plant cooldown. j Based upon this, the plant ability to reach hot standby:and subsequently j cold shutdown conditions, as required- by Appendix R, will not be impacted :

by this proposed change. !

)

In summary, the proposed revision to reduce the required BAT boron concentration will maintain shutdown margin requirements,_and will !

eliminate the operational problems associated with maintaining high boron ,

concentrations.

Environmental Impact Evaluation The proposed change request does not involve an unreviewed environmental-question because operation of SQN Units 1 and 2 in accordance with this change would not:

1. Result in a significant increase in any adverse environmental impact previously evaluated in the Final Environmental Statement (FES) as modified by the staff's testimony to the Atomic Safety and Licensing Board, supplements to the FES, environmental impact appraisals, or l decisions of the Atomic Safety and Licensing Board.

2. Result in a significant change in effluents or power levels.

3. Result in matters not previously reviewed in the licensing basis for SQN that may have a significant environmental impact.

u l

1

-,. ~ ,

t l

Enclosure 3 i

PROPOSED TECHNICAL SPECIFICATION CHANGE SEQUOYAH NUCLEAR PIANT UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 (IVA-SQN-TS-92-08 ) ;

DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION T

e 1

t 1

i l

1 l

1

Significant Hazsrds Evaluation TVA has evaluated the proposed technical specification (TS) change and has determined that it does not represent a significant hazards l consideration based on criteria established in 10 CFR 50.92(c).

Operation of Sequoyah Nuclear Plant (SQN) in accordance with the proposed amendment will not:

1. Involve a significant increase in the probability or consequences of an accident previously eveluated.

The reduction of the boric acid concentration in the boric acid tanks 1 (BAT) and elimination of requirements for the associated heat trace circuits will not significantly increase the probability or consequence of an accident previously evaluated. Only minor modifications are planned; and while operating processes will change to reflect the new boration method, the capability to safely shut down has not been changed or modified. TS controls have been placed '

on the boric acid storage system to ensure that the lack of heat tracing does not result in the boron precipitating out of solution.

Originally, SQN had the ability to borate at 10 gallons per minute i (gpm) with a boron solution of 20,000 parts per million (ppm). With the proposed change, SQN will provide the ability to borate at 35 gpm with a solution of between 6,120- to 6,990-ppm boron. This will i ensure that the boron addition rate remains essentially the same. In I addition, as boron addition from the BATS is not taken credit for in any accident analysis, the probability or consequences of any accident previously evaluated will not be affected. '

As part of this TS change, for consistency Mode 4 was remuved from TS 3.1.2.6 and placed in TS 3.1.2.5. The analysis performed supports the relocation and demonstrates that there is sufficient borated water volume and concentration to provide the required shutdown margin. Based upon this analysis, this change does not involve a i significant increase in the probability or consequences of an i accident previously evaluated.

2. Create the possibility of a new or different kind of accident from any previously analyzed.

The original SQN design required heat trace circuits to ensure the boron, which was at 12 percent by weight, would remain in solution ;

and be available for reactor coolant system reactivity control i '

throughout core life. By lowering the boron concentration to approximately 3.5 to 4.0 percent by weight, chemical analysis has shown there is no possibility of boron precip?tating out of solution as long as the boric acid solution remains above 58 degrees ,

Fahrenheit (F). The auxiliary building, where this equipment is located normally, remains well above 58 degrees F. Continuous j monitoring of the required area temperatures, in conjunction with an alarm in the main control room, will. allow for operator actions to ensure the solution temperature remains above the TS-required temperature of greater than or equal to 63 degrees F. By eliminating the need for the heat trace, there is an increase in the availability of the boric acid storage system. In addition, the boron concentration remains well above expected RCS concentration.

Therefore, the removal of requirements for heat trace circuits and l

l l

the reduction of the boron concentration in the BATS do not create the possibility of a new or different kind of accident from any previously analyzed.

As previously stated, Mode 4 has been deleted from TS 3.1.2.6 and I added to TS 3.1.2.5 to provide consistency between these two TSs and TSs 3.1.2.1 and 3.1.2.2. The analysis provides the basis that sufficient shutdown margin still remains to meet the TS requirement for Mode 4 when it is added to TS 3.1.2.5. Therefore, this change does not create the possibility of a new or different kind of accident from any previously analyzed.

3. Involve a significant reduction in a margin of safety.

The margin of safety requirements is not affected by the removal of the heat trace circuits and the reduction of the boric acid concentration in the BATS. The required flow paths and borated water sources are still available as before. The required quantity of borated water is still available based upon the new evaluation, and the ability to deliver this borated water remains the same. As stated previously, the reduction of the boric acid concentration in the BATS will ensure that the boric acid remains in solution at the normal room temperature in the auxiliary building. To ensure this, ambient temperatures will be periodically verified. With the above changes, there will be a net improvement in system reliability and, accordingly, the proposed changes do not affect the margin of safety.

Moving Mode 4 applicability from TS 3.1.2.6 to TS 3.1.2.5 does not involve a reduction in the margin of safety. This is supported by the analysis, which establishes the minimum boron requirements to ensure that there still remains adequate shutdown margin for cooldown below 350 degrees F (Mode 4).

i l

l

B ENCLOSURE 4 PROPOSED TECHNICAL SPECIFICATION CHANGE SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 DOCKET NOS. 50-327 AND 50-328 l ,

t r l

(TVA-SQN-TS-92-08) ,

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REVISION 2 TECHNICAL BASES AND OPERATIONAL ANALYSIS FOR ,

SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 (B88 930211 001) l 1

9 i

I l

L gg g B88 930211 001 BORIC ACID

/ -

CONCENTRATIO'N REDUCTION EFFORT CEN-602, REV. 2 E

- APPROVED '

TECHNICAL BASES e2',::::;L'::::::,':t":,**

r; t.ut *;: :::::l " d AND _ Letter No. 30M199

':J e "*" 1 1993 vonesstz muy arwomry -

OPERATIONAL ANALYSIS t **" (") ~"' t FOR ,

is t '

z ~,

$ SEQUOYAH NUCLEAR PLANT c

, 5. e R

d g 8

h I.

j j 8

UNITS 1 AND 2 gg R "

o c e8 i s

a 4T E .?

w lE .2 6 a l !8 PREPARED FCR o o wlc :o s q TEENESSEE 7 ALLEY AUTHORITY wu o BT dE.8hn oE8o w ABB CCEBUSTION ENGINEERING NUCLEAR SERVICES E88 AUTHCR: W -

Nb

/

QA REVIEW: _W A 8 h 3 Feh 9.19T3 vwvu -

i l

EIMS,ET ILE-E :

l

I f

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAI, ANALYSIS l Table of Contents l Section Title pace

1.0 INTRODUCTION

. . . . . . . . . . . . . . . . . ..... 6 1.1 PURPOSE AND SCOPE . . . . . . . . . . . . . . .... . 6 1.2 REPORT ORGANIZATION . . . . . . . . . . . . . .... . 8 1.3 PAST vs. PRESENT METHODOLOGY OF SETTING BAT CONCENTRATION 9 2.0 TECHNICAL BASES FOR REDUCING BAT CONCENTRATION . . . . . 12 2.1 BORIC ACID SOLUBILITY . . . . . . . . . . . . . . . . . 12 2.2 METHOD OF ANALYSIS AND ASSUMPTIONS . . . . . . . . . . . 12 2.2.1 RCS Boron Concentration vs. Temperature . . . 12 2.2.2 Impact of Cooldown Rate . . . . . . . . . . . 20 2.2.3 Aeolicability to Future Reload Cycles . . . . 22 2.2.4 Boron Mixina in the RCS and in the Pressurizer . . . . . . . . . . . . . . . . . 22 2.3 BORATED WATER SOURCES - SHUTDOWN (MODES 4 AND 5) . . . . 23 2.3.1 Boration Reauirements for Modes 4 and 5 . . . 23 2.3.2 Assumptions Used in the Modes 4 and 5 Analysis . . . . . . . . . . . . . . . . . . . 24 2.3.3 Modes 4 and 5 Analysis - Outline . . ... . . 24 2.3.4 Modes 4 and 5 - Cooldown - Makeup.from RWST. . 26 2.3.5 Refuelina Water Storace Tank Boration Reauirements - Modes 5 & 6. . . . . . ........ 31 2.3.6 Modes 4 and 5 Cooldown -

Blended Makeuo from BAT. . . . . . . . . . . . 32 ABB Combustion Engineering Nuclear Services Page 2 of 167

i l

\

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Table of Contents (continued)

Section Title / Pace 2.3.7 BAT Storace Recuirements - Modes 4 and 5 . . . 32 l l

2.4 BORATED WATER SOURCES - OPERATING (MODES 1, 2, and 3) . 34 2.4.1 Boration Recuirements for Modes 1. 2. and 3 . . 34 l 2.4.2 Assumptions Used in the Modes 1. 2. and 3 Analysis . . . . . . . . . . . . . . . . . . . 34 2.4.3 Modes 1, 2, and 3 Analysis Results-Eauilibrium Xenon Scenario . . . . . . . . . . 36 2.4.4 Modes 1, 2, and 3 Analysis Results-Xenon Free Scenario . . . . . . . . . . . . . 41 l 2.4.5 Simolification Used Followina RHRS l Initiation . . . . . . . . . . . . . . . . . . 48 2.5 BORATION SYSTEMS - BASES . . . . . . . . . . . . . . . . 49 2.5.1 Derivation of the 57.000 Gallon Volume -

(RWST) . . . . . . . . . . . . . . . . . . . . 50 2.5.2 Derivation of the 26,000 Gallon RWST Volume Recuired when the Smallest BAT Volume is Used . . . . . . . . . . . . . . . . . . . . . 51 2.6 ACTION STATEMENTS ON FLOW REQUIREMENTS . . . . . . . . . 52 TABLES - SECTION 2 . . . . . . . . . . . . . . . . . . 56 FIGURES - SECTION 2 . . . . . . . . . . . . . . . . . 122 3.0 OPERATIONAL ANALYSIS . . . . . . . . . . . . . . . . . . 130

3.1 INTRODUCTION

TO THE OPERATIONAL ANALYSIS . . . . . . . . 130 ABB Combustion Engineering Nuclear Services Page 3 of 167

l l

i i

l l

BORIC ACID CONCENTRATION REDUCTIOtt EFFORT CEN-602, REY.2 i TECHNICAL BASES AND OPERATIONAL ANALYSIS I

Table of Contents (continued) l Section Title Pace '

i 3.2 RESPONSE TO EMERGENCY SITUATIONS . . . . . . . . . . . . 130 {

3.2.1 Accident Boration Reauirements . . . . . . . . 131 !

3.2.2 Shutdown Marain Recoverv . . . . . . . . . . . 132 3.2.3 Emeroency Boration . . . . . . . . . . . . . 132 l

3.3 FEED-AND-BLEED OPERATIONS . . . . . . . . . .. . . . . 133 r

s 3.4 BLENDED MAKEUP OPERATIONS . . . . . . . . . . . . . . . 136 !

3.5 SHUTDOWN TO REFUELING - MODE 6 . . . . . . . . . . . . . 137 l l

3.6 SHUTDOWN TO COLD SHUTDOWN - MODE 5 . . . . . . . . . . - . 141 '

i '

i 3.7 LONG TERM COOLING AND CONTAINMENT SUMP pH . . . . . . . 143 j i

i TABLES - SECTION 3 .. . . . . . . . .. . . . . . . . . 144 ;

FIGURES - SECTION 3. . . . . . . . . . . . . . . . . . . 157 !

4.0 REFERENCES

. . . . . . . . . . . . . . . . . . . . . . 167 l

l ABB Combustion Engineering Nuclear Services Page 4 of 167

1 I

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECENICAL aASES AND OPERATIONAL ANALYSIS !

Table of Contents (continued)

Section Title Pace i

List of Anoendices !

Appendix 1 Derivation of the Reactor Coolant System Feed-and-Bleed Equation . . . . . . . . .. . Al-1 Appendix 2 A Proof That Final System Concentration is Independent of System Volume . . . .. . . A2-1 Appendix 3 Methodology for Calculating Dissolved Boric Acid per Gallon of Water. . . . . .. . A3-1 1

Appendix 4 Methodology for Calculating the Conversion Factor Between Weight Percent Boric Acid and ppm Boron . . . . . . . . . . . . .. . . A4-1 t

Appendix 5 Bounding Physics Data Inputs. . . . . .. . . AS-1 l

l ABB Combustion Engineering Nuclear Services Page 5 of 167 l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS

1.0 INTRODUCTION

This revision has been prepared to incorporate comments and recommendations received from TVA following their review of the initial reports. As requested, this revision includes the analysis of a plant cooldown from hot, zero power conditions, with core xenon concentration at post-trip peak at the time cooldown is initiated. This case replaces the study of cooldown from equilibrium xenon conditions. As reported in the previous revision, this report also incorporates the Mode 4 volume storage requirement from

" Borated Water Sources - Operating" to " Borated Water Sources - Shutdown", so as to make the Borated Water Sources Technical Specification consistent with the Flow Path Technical Specification.

1.1 PURPOSE AND SCOPE This report defines the methodology and outlines the technical bases which allow a reduction in the Boric Acid Tank (BAT) concentration to the point where heat tracing of the boric acid makeup system is no longer required in order to prevent boric acid precipitation. The current i methodology or procedure used to set the minimum BAT !

concentration and level for Modes 1, 2, and 3 is to allow a 1

plant shutdown-to-cold-shutdown at any time into the fuel cycle, using a feed-and-bleed procedure. For purposes of I implementing the requirements for heat removal capability for compliance with this position, plants were divided into three classes by the NRC. Sequoyah Units 1 and 2 have been classified as Class 2 plants per BTP 5-1. Class 2 is i

defined as follows in the Branch Technical Position: 1 I

l ABB Combustion Engineering Nuclear Services Page 6 of 167 j i

T I

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS

" Partial implementation of this position for all plants (custom or standard) for which CP or PDA applications are docketed on or after January 1, 1978 and for which an OL issuance is expected on or after January 1, 1979."

A table is included in the BTP which describes recommended implementation for Class 2 plants.

Two defined boration flow paths with appropriate borated water sources are provided in Sequoyah Units 1 and 2 to compensate for reactivity changes and all expected transients throughout core life. These boration flow paths are the BATS and the refueling water storage tank (RWST).

The design bases used to establish the required volume and boron concentration in the BAT have been reexamined, and the results are presented in this Section. In addition, the minimum RWST volume requirements for RCS boration have been recalculated. Sufficient dissolved boric acid must be maintained in the BATS to provide the shutdown margin specified in Technical Specification 3.1.1.1 for a cooldown from hot standby (Mode 3) to cold shutdown (Mode 5) conditions. Further, both the minimum level and boron concentration which must be maintained in the BAT for Modes l 4, 5, and 6 are based upon the ability to maintain the shutdown margin specified in T.S. 3.1.1.1 (Mode 4) and T.S.

3.1.1.2 (Modes 5 and 6) following xenon decay and cooldown j I

from 350'F to 135'F.

This document has been prepared to support a reduction in 1 the concentration and volume of boric acid which must be l maintained in the BATS at Sequoyah Units 1 and 2 to maintain adequate shutdown margin, and to show that this margin can l l

ABB Combustion Engineering Nuclear Services Page 7 of 167

l 1 i l

l I l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 '

j TECHNICAL BASES AND OPERATIONAL ANALYSIS ;

l be provided by one (1) BAT for each unit, with additional l makeup from the RWST for contraction, and a feed-and-bleed, if required. The studies, described herein support a j reduction in boric acid concentration to levels below that at which precipitation can occur at the temperatures l normally expected in the BAT and associated piping areas of j

! the plants. This reduction will eliminate the requirement j for heaters and heat tracing on this equipment. To '

accomplish this, the analysis performed to support the ;

original requirements for boric acid has been reevaluated, t incorporating the revised boration-to-cold-shutdown methodology. This methodology has been developed to '

demonstrate the acceptability of reducing the concentration and volume of stored boric acid.

The work described in this report was performed specifically for Sequoyah Units 1 and 2. To the extent possible, the calculations performed and the values obtained will be applicable to future fuel cycles. (See Section 2.2.3

, below.) The physics parameters used in this analysis have been selected conservatively to bound core physics parameters for the remainder of plant life. Future cycle core physics parameters are to be compared to the data in Appendix 5 to ensure that the results of these calculations remain bounding. The values in Technical Specification Figure 3.1.2.6 may change slightly; however, there should not be a need to heat trace the piping and components of the boric acid system for the remainder of plant life.

1.2 REPORT ORGANIZATION l

This report has been organized into three sections:

Introduction, Technical Bases, and Operational Analysis. In ABB Cornbustion Engineering Nuclear Services Page 8 of 167 l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l

Section 2.0, titled " Technical Bases for Reducing BAT Concentration", the methodology which allows a significant reduction in BAT concentration and volume is outlined, and the results of the detailed calculations performed in support of the Technical Specifications are presented.

Separate calculations were performed for Specification l 3.1.2.5 (Borated Water Source - Shutdown), Specification 3.1.2.6 (Borated Water Source - Operating), as well as Specification B3/4.1.2 (Boration Systems Bases). In addition, revised action statements have been prepared for Specification 3.1.1.1 (Boration Control / Shutdown Margin /T,y, Greater Than 200'F), Specification 3.1.1.2 (Reactivity i

Control Systems / Shutdown Margin /T,y, >200*F), Specification 3.9.1 (Refueling Operations / Boron Concentration), and in Specification 3.10.1 (Special Test Exception / Shutdown Margin), and Specification 4.1.2.2.d, (Reactivity Control Systems / Flow Paths Operating / Surveillance Requirements) .

In Section 3.0, " Operational Analysis", the impact of the reduction in the concentration of boric acid stored in the BATS on normal operations is outlined. The operations evaluated in Section 3.0 are as follows: feed-and-bleed, blended makeup, shutdown to refueling, and shutdown to cold shutdown. Tables and figures are contained at the end of each section for convenient reference.

1.3 PAST vs. PRESENT METHODOLOGY OF SETTING BAT CONCENTRATION Prior to the development of the new methodology for setting BAT concentration and level described in this report, the level and concentration specified in the plant Technical Specifications for Modes 1, 2, 3, and 4 were based upon setting the minimum BAT volume and boron concentration to ABB Combustion Engineering Nuclear Services Page 9 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l allow a plant shutdown-to-cold-shutdown at any time during the fuel cycle, using a feed ,and-bleed procedure. Using the old methodology, the reactor coolant system (RCS) was borated prior to initiating cooldown to the boron concentration required to provide a shutdown margin at 200*F l

i of 1.6% Ak/k (refer to Technical Specification 3/4.1.1.1).

! Review of the initial plant design for the BAT volume is

( contained in Section 5.3.2 of the NRC Safety Evaluation Report (SER), Supplement 1. In Supplement 1 to the SER, it was originally assumed that loss of the non-seismically l qualified air supply resulted in loss of letdown capability.

t Boration without letdown can be accomplished using safety grade equipment. In this limiting situation, with letdown l unavailable, boration was accomplished by charging to the l RCS (consequently filling the pressurizer). Since boron ;

l concentration in the RCS typically had to be increased by approximately 1000 ppm prior to commencing cooldown, the limited volume available in the pressurizer resulted in a requirement for storing highly concentrated boric acid solution in the BATS.

However, subsequent to the issuance of the SER, the design of Sequoyah Units 1 and 2 provides the capability for letdown of reactor coolant assuming a single failure and loss of either off-site or on-site power,using safety-grade equipment.

The methodology for setting concentration and level of Modes l 1, 2, and 3 described in this report differs from previous methodologies in that boration of the RCS is performed concurrently with plant cooldown. Concentrated boric acid is added concurrently with cooldown to compensate for contraction of the primary coolant; this is accompanied by ABB Cornbustion Engineering Nuclear Services Page 10 of 167

l l

i BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2

[

TECHNICAL BASES AND OPERATIONAL ANALYSIS conducting a feed-and-bleed at a temperature of 400*F or above to increase the boron concentration in the system.

By ;

determining the boron concentration required to maintain ;

proper shutdown margin at each temperature during a plant cooldown, the concentration of boric acid in the BATS can be !

decoupled from available pressurizer volume. As the present study shows, the concentration of boric acid which must be i maintained in the BATS to allow cooldown to cold shutdown I i

conditions can be reduced to a value between 3.5 and 4.0 weight percent, where heat tracing of the boric acid system ;

is no longer required, i.e., the ambient temperature in the ;

auxiliary building is sufficient to prevent boric acid precipitation.

Similarly, this new methodology was utilized in setting the minimum concentration and level of the beration source which is required to be operational in Modes 4, 5, and 6. Since letdown is available in the cooldown scenarios of Modes 4, 5,and 6, feed-and-bleed may be conducted in order to increase RCS boron concentration, while boric acid is added as normal makeup during cooldown. By insuring that the boron concentration is maintained greater than that required for proper shutdown margin at each t'emperature, the concentration of boric acid in the BATS for Modes 4, 5, and 6 can be lowered to a value between 3.5 and 4.0 weight

~

percent.

l ABB Combustion Engineering Nuclear Services Page 11 of 167 ,

i

BORIC ACID CONCENTRATION REDUCTIoM EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l l

2.0 TECHNICAL BASES FOR REDUCING BAT CONCENTRATION I

2.1 BORIC ACID SOLUBILITY Figure 2-1 is a plot of solubility of boric acid in water vs. temperature, for temperatures between 32*F and 160*F.

The data for Figure 2-1 was obtained from reference 4.2 and ,

is included herein as Table 2-1. Note that the solubility of boric acid at 32*F is 2.52 weight percent and at 58'F is 4.00 weight percent. At or below a concentration of 4.0 weight percent boric acid, the normal ambient temperature in the auxiliary building will be sufficient to preclude precipitation within the Boric Acid Makeup Subsystem.

Maintenance of the ambient temperature is further ensured by Technical Specification Surveillance Requirements.

2.2 METHOD OF ANALYSIS AND ASSUMPTIONS 2.2.1 RCS Boron Concentration vs. Temoerature 2.2.1.1 Operating Modes 1, 2, and 3 -

Peak Xenon Scenario .

As stated in Section 1.3 above, the methodology developed to :

justify a significant reduction in the concentration of f

boric acid which must be maintained in the BATS in Modes 1, 2, and 3 differs from the previous methodology in that boration of the RCS is performed concurrently with cooldown.

In order to insure adequate shutdown margin during the cooldown process, concentrated boric acid solution is added as part of normal system makeup. To employ a methodology allowing boration concurrent with cooldown, the exact boron

{

concentration in the reactor coolant necessary to maintain ABB Combustion Engineering Nuclear Services Page 12 of 167 i

i

i I

I BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 j TECHNICAL BASES AND OPERATIONAL ANALYSIS the required shutdown margin must be known at any temperature during the cooldown process. In addition, in order to insure applicability for the entire fuel cycle, a conservative cooldown scenario has been developed which

! incorporates the maximum increase in RCS boron concentration l which the operator must achieve in order to maintain an adequate shutdown margin at the most limiting time in the fuel cycle. Such a limiting scenario is as follows:

l

1. Conservative core physics parameters are used to determine both the concentration and the volume of boric acid solution which must be provided from the BAT's during plant cooldown. Near end-of-life (EOL) initial boron concentration is assumed to be zero, with xenon concentration in the core at the post-trip peak at the time cooldown is initiated. EOL moderator cooldown effects are used to maximize the reactivity change during the plant cooldown. EOL values of inverse boron worth (IBW) were used in combination with EOL moderator reactivity insertion rates, normalized to the most Negative Technical Specification Moderator Temperature Coefficient (MTC) limit, since it is known that this yields results that are more limiting than any actual combination of MTC and IBW values throughout l the fuel cycle. These assumptions assure that the i required concentration of boron and the minimum volume requirements for the BAT conservatively bound all plant cooldowns during core life.

2. The most reactive rod is stuck in the full out position.

ABB Combustion Engineering Nuclear Services Page 13 of 167

l l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l

3. Prior to time zero, the plant is operating at 100%

power, with core xenon concentration at the 100% power equilibrium level.

4. There is zero RCS leakage.

5. At time zero, the plant is shutdown and held at hot zero power conditions for approximately 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months , at which time the xenon transient after shutdown will have ,

reached its peak. During this 8-hour interval, the plant is diluted to zero (0) ppm boron.

6. For conservatism, reactor coolant average temperature has been assumed to be 547'F, rather than the higher temperature associated with natural circulation conditions (572 *F) . This results in a lower volume of coolant contraction, and, as a consequence, a lower volume and mass of boric acid solution which can be added to compensate for the contraction.

7. At time = 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months , with core xenon concentration at post-trip peak, a cooldown-to-cold-shutdown is initiated.

The scenario outlined above has been used to generate the i boration requirements for Modes 1, 2, and 3 (Technical l

Specification 3.1.2.6). It produces a situation wherein !

positive reactivity will be added to the reactor core from i

two sources at the time cooldown-from-hot-shutdown is i l

initiated. The two reactivity sources are (1) , the 1

temperature effect due to an overall negative isothermal temperature coefficient of reactivity, and (2), the poison (xenon) effect due the decay of xenon-135 below the post-l ABB Combustion Engineering Nuclear Services Page 14 of 167 i

l

BORIC ACID CONCENTRATION REDUCTION RFFORT CEN-602, REY.2 TrenNIcAL mAsrs AND OPERATIONAL ANALYSIS trip peak. This scenario, therefore, represents the greatest operational challenge in meeting the requirement ;

for boration of the RCS and maintaining the shutdown margin required by the Technical Specifications while cooling the e plant from hot standby to cold shutdown conditions.

Although this specification is only applicable to Modes 1, 1 2, and 3, the volumes stored in the BASTS provido for boration to Mode 5 (Cold' Shutdown). .

2.2.1.2 Operating Modes 1, 2, and 3 -

Xenon Free Scenario An additional scenario has been considered for this study.

In this case, the bounding assumptions in Section 2.2.1.1 have been modified to cover the condition of a xenon-free core. The assumptions governing the analysis of this condition are as follows: ,

l I

1. Conservative core physics parameters are used to determine both the concentration and the volume of boric acid solution which must be provided from the BATS during plant cooldown. End-of-life (EOL) initial boron concentration is assumed to be zero. EOL l moderator cooldown effects are used to maximize the reactivity change during the plant cooldown. EOL values of inverse boron worth (IBW) were used in combination with EOL moderator reactivity insertion rates, normalized to the most Negative Technical Specification Moderator Temperature Coefficient (MTC) limit, since it is known that this yields results that are more limiting than any actual combination of MTC and IBW values throughout the fuel cycle. These assumptions assure that the required boron concentration and the BAT minimum volume requirements ABB Combustion Engineering Nuclear Services Page 15 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l

conservatively bound all plant cooldowns during core life.

l 2. The most reactive rod is stuck in the full out position.

3. Prior to time zero, the plant is operating at 100%

l power, with core xenon concentration at the 100% power equilibrium level.

l

4. There is zero RCS leakage.

l S. At time zero (t=0), the plant is shut down and held in 1

the hot, zero power condition for 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . At the end of this period, the core xenon concentration will have peaked. During this 8-hour interval, the RCS is diluted to zero ppm boron to match the boron requirement.

6. The plant is held at hot, zero power conditions for 142 additional hours. At the end of this period, the xenon in the core will have decayed, leaving the core essentially in a xenon-free condition. To maintain the requisite shutdown margin as the xenon aecays, a feed-and-bleed is conducted from the BAT, raising the boron concentration to 579 ppm.

7. At the end of this delay, (t=150 hrs), a cooldown-to-cold-shutdown is initiated.

l This analysis has been performed to determine the storage requirements, should conditions exist which result in the plant operating staff holding the plant at hot, zero power ABB Combustion Engineering Nuclear Services Page 16 of 167

l l

nomIc AcIn oowczwraArzou mapucrzou arront cEN-602, REV.2 TrenwIcAL anses AND oPERATIoNAI, ANALYSIS i

conditions for an extended period of time, during which the ;

core xenon concentration peaks and subsequently decays to a xenon-free condition. In the analysis, the two elements adding positive reactivity to the core are treated. While at the hot, zero-power condition, the plant must be borated 6 to maintain the required shutdown margin. This additional boration is needed to maintain the required shutdown margin, ,

compensating for the xenon decay. When cooldown is initiated, additional boration will take place as makeup from the BAT and RWST is added to compensate for coolant contraction, along with an RWST feed-and-bleed. Since the core is then xenon-free, the required boron concentration f will be a function solely of temperature and will be independent of cooldown rate.

2.2.1.3 Operating Modes 4, 5, and 6 !

The applicability for Mode 4 " Borated Water Sources", has been changed from Technical Specification 3.1.2.6, " Borated Water Sources - Operating" to Technical Specification 3.1.2.5, " Borated Water Sources - Shutdown". The change in applicability serves to make the " Borated Water Sources" l

specification applicable during the same Modes as in the

! " Flow Paths - Operating" and " Flow Paths - Shutdown" specifications. With this change in applicability, the l results of the " Borated Water Sources - Shutdown" analysis provide sufficient boric acid solution for the cooldown from 350*F to 135'F.

The methodology developed to determine the requirements for boration in Modes 4 and 5 differs from the method used in previous refueling cycles. Consistent with the new I

methodology, boration of the RCS is performed concurrently l ABB Combustion Engineering Nuclear Services Page 17 of 167 l

4 BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECENICAL BASES AND OPERATIONAL ANALYSIS with cooldown. Concentrated boric acid is added during the cooldown evolution as part of normal system makeup. To employ this methodology, the exact boron concentration required in the RCS must be known throughout the temperature range during the cooldown process. The following scenario I

was developed to identify the most limiting cooldown transient for Modes 4 and 5.

1. EOL conditions are assumed, with the initial boron concentration in the reactor coolant at the level necessary to provide a shutdown margin of 1.6% Ak/k at 350*F and with a xenon free core. EOL MTC effects are used to maximize the reactivity change during the plant cooldown. IBW data at EOL were used in conjunction with EOL MTC reactivity insertion rates normalized to ;

the most Negative Technical Specification Moderator I l

Temperature Coefficient (MTC) limit, since it is known j that this yields results more limiting than does any actual combination of MTC and IBW values throughout the fuel cycle.

2. The most reactive rod is stuck in the full out position.

3. There is zero RCS leakage.

4. RCS feed-and-bleed can be used to increase boron concentration.

5. RCS makeup is supplied either from the RWST alone or from a blended combination of makeup from the BAT and the Primary Water Storage Tank (PWST).

ABB Combustion Engineering Nuclear Services Page 18 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 j TECHNICAL BASES AND OPERATIONAL ANALYSIS i

6. The most limiting scenario for boration in Modes 4 and 5 requires that a shutdown margin of 1.6 % Ak/k be maintained during the cooldown from 350*F to 200*F, and a shutdown margin of 1.0 %Ak/k be maintained during the cooldown from 200*F to 135*F.

In mode 6, with the reactor vessel head detensioned or !

removed, a boron concentration sufficient to ensure the more restrictive of the following reactivity conditions must be maintained:

A K,,, of 0.95 or less, which includes a conservative allowance for uncertainties of 1% AK/K, or 2000 ppm.

If the required shutdown margin for Mode 6 is not maintained, the current Technical Specification 3.9.1 requires that the RCS be borated at 10 gpm from a source of borated water at a concentration 120,000 ppm boron or its equivalent. Technical Specification 3.1.2.5 requires that either the RWST or at least one of the BATS be available to meet this requirement consistent with flow path mode requirements. (NOTE: See Section 2.6 of this report for the modification to the action statement.)

In this scenario, positive reactivity is added to the reactor core due to the overall negative isothermal temperature coefficient of reactivity. Since the core is already assumed to be xenon free, there is no contribution to core reactivity from xenon decay.

1 1

l 1

ABB Combustion Engineering Nuclear Services Page 19 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAI, EASES AND OPERATIONAL ANALYSIS 2.2.2 Imoact of Cooldown Rate As discussed in the previous Section, a conservative cooldown scenario was selected for use in determining the boron concentration levels required in the RCS. These concentration results were then used to define the minimum Technical Specification BAT tank inventory requirements. In the peak xenon scenario for Modes 1, 2, and 3, positive reactivity was added concurrently from two sources at the time that plant cooldown from hot standby was initiated.

The component resulting from an overall negative isotho A1 temperature coefficient of reactivity is independent of time but is directly dependent on the change in coolant temperature. In contrast, the component resulting from the decay of xenon-135 below post-trip peak is independent of temperature but is directly dependent on time. As a result, for a given temperature decrease, a slow cooldown rate will require the addition of more boron ".o the reactor coolant than will a fast cooldown rate, sir,ce compensation must be provided for the larger amount of positive reactivity due to xenon decay. As shown in the data provided by Reference 4.3 a limiting overall cooldown rate of 10*F/hr has been established for Sequoyah Units 1 and 2. The boron concentration requirements associated with this transient are illustrated in Figure 2-2. The bases for Technical Specification 3.1.2.5 include the consideration of a cooldown following xenon decay. As a result, boration requirements are independent of cooldown rate for the analysis of Modes 4 and 5.

The slow boration rate was selected to determine the maximum required boron concentration as a function of temperature.

(At higher cooldown rates, the plant reaches the shutdown ABB Cornbustion Engineering Nuclear Services Page 20 of 167

BORIC ACID CONCENTRATION REDUCTION ErrORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS margin transition temperature in Mode 5 sooner, when the core xenon concentration is higher). Injection flow rate was not a consideration.

An effective cooldown rate of 10*F/hr was used for the determination of the required volume of boric acid solutionand the boron concentration of that solution in the BATS duringModes 1, 2, and 3; these calculations establish the Technical Specification limits for these parameters.

This slow cooldown rate was selected to ensure that the required volume of boric acid solution was chosen conservatively. (General Operating Instruction GOI-3 specifies an allowable cooldown rate of 50*F/hr for the RCS and 100*F/hr for the Pressurizer; in addition, the steam generators must be soaked for eight (8) hours with reactor coolant temperature maintained between 290*F and 310*F before completing the cooldown.) As shown in Table 2-2, taking the plant from hot standby to cold shutdown (a change of 347'F) required 34.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months , including an initial delay of 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months at hot standby and an additional 4.82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months for I added conservatism. An effective cooldown rate, therefore, of 10*F/hr was required to cool the plant from an average c.oolant temperature of 547'F to an average coolant temperature of 200*F in 34.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months . This scenario will conservatively bound cooldowns that occur earlier and/or at higher cooldown rates. The above scenario bounds the reactivity effects of a BTP 5-1 cooldown. It is assumed in the BTP 5-1 scenario that Safety Grade plant equipment will be capable of bringing the RCS to RHRS entry conditions within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months after cooldown is initiated. In a cooldown from xenon-free initial conditions, there is no reactivity added by xenon decay, and the 10*F/hr limit is even less restrictive.

ABB Combustion Engineering Nuclear Services Page 21 of 167

i 1

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS 2.2.3 Anolicability to Future Reload Cycles I

To ensure that the current analysis will be valid for future I cycles, conservative data from Sequoyah bounding both Units 1 and 2 was utilized. It is anticipated that the physics data used in this analysis will bound future fuel cycles of ,

I similar reload cores. Appendix 5 contains the bounding ;

physics assumptions used to produce the required boron concentration values. As long as the input is more l conservative than the physics parameters used in this analysis, the values generated in this analysis and presented in this report will bound the boron concentration l

values for future reload cycles.

l l

2.2.4 Boron Mixina in the RCS and in the Pressurizer l

A constant pressurizer level was assumed throughout the cooldown calculations described in Sections 2.3 and 2.4 below, i.e., plant operators charged to the RCS only as necessary to makeup for coolant contraction. In this situation, the driving force for the mixing of fluid between l l

the RCS and the pressurizer is small.

l l

As a conservatism, complete and instantaneous mixing was assumed between all makeup fluid added to the reactor I coolant system through the loop charging nozzles and the l l

pressurizer. Further, system pressure must be reduced '

during the plant cooldown process, as indicated in Section 1 2.4 of this report. This pressure reduction is necessary to ensure that the Reactor Vessel Pressure-Temperature limits are not violated; it is also required since the RHRS is a i

low pressure system and is normally aligned at or below an l l

RCS pressure not greater than 380 psia; in this analysis, '

ABB Combustion Engineering Nuclear Services Page 22 of 167 l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS realignment was assumed to occur at a pressure of 350 psia.

l During a natural circulation cooldown, this depressurization l

j is typically performed using the auxiliary pressurizer spray system. As an added conservatism in the analyses for Modes 1, 2, and 3, boron added to the pressurizer via the spray system was assumed to remain in the pressurizer and thus to be unavailable for mixing with the fluid in the remainder of the RCS.

2.3 BORATED WATER SOURCES - SHUTDOWN (MODES 4 AND 5) l 2.3.1 Boration Recruirements for Modes 4 and 5 As stated in the plant Technical Specifications, a boration capacity sufficient to provide a shutdown margin of 1.6

%Ak/k is required at temperatures greater than 200*F, and a boration capacity sufficient to provide a shutdown margin of 1.0% Ak/k is required following xenon decay at temperatures less than or equa' to 200*F . This beration capability is sufficient to prcude the required shutdown margin during a plant cooldown from 350*F to 135'F.

The required RCS boron concentrations were determined on this basis using conservative core physics data furnished by Reference 4.3 for temperatures of 350*F, 300*F, 250*F, 200*F and 135'F. Intermediate points were determined by linear interpolation. The restits are given in Table 2-3 and are plotted as the required shutdown curve (curve 1) in Figures 2-3 and 2-4. Note that a total increase of 176.0 ppm in the boron concentration is required for the cooldown from 350*F to 135'F.

ABB Combustion Engineering Nuclear Services Page 23 of 167

l l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2

TECHNICAL RASES AND OPERATIONAL ANALYSIS 2.3.2 Assumotions Used in the Analysis of Modes 4 and 5 A complete list of assumptions and initial conditions used i in calculating the minimum BAT inventory requirements for Modes 4, 5, and 6 is contained in Table 2-4. In the process of taking the plant from hot standby to cold shutdown, the RHRS will normally be aligned after entering Mode 4, i.e., 1 when the RCS temperature and pressure have been lowered to approximately 350*F and 350 psia. As shown in the next !

Section, the total system volume, i.e., RCS volume, plus pressurizer (PZR) volume, plus RHRS volume, must be known l

for the analysis of Modes 4 and 5 cooldowns. The exact 4 volumes of each of these have been determined for use in i

this analysis to establish the BAT inventory requirements.

I The system volume used in the calculation of Modes 4 and 5 is as follows:

(RCS volume) + (PZF volume at 0% power) + (RHRS Volume) or 1

(10,812 f t ) + (444.6 ft ) + (1500 f t ) = 12,756.6 ft 2.3.3 Modes 4 and 5 - Analysis - Outline As noted in Section 2.3.1, the required boration capacity is based upon providing shutdown margins of 1.6 %Ak/k at RCS temperatures greater than 200*F and of 1.0% Ak/k following xenon decay and a plant cooldown from 200*F to 135"F. The operating scenario employed in determining the required RCS boron concentration and ensuring that proper shutdown margin will be maintained is as follows: l ABB Combustion Engineering Nuclear Services Page 24 of 167 i

( , _ _

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS A. The systems are initially at a temperature and pressure of 350*F and 350 psia. The initial boron concentration in the RCS, pressurizer, and the RHRS is 1047 ppm boron, to provide the required shutdown margin. The RHRS is aligned and in operation. The assumption of a xenon-free core is conservative. Using the methodology of boration-to-makeup-for-contraction in conjunction with a limited feed and bleed operation, the boron concentration at 350*F will be greater than the required concentration for a xenon-free core at 350*F.

(See Table 2-4 for a complete list of assumptions.)

B. With charging limited to makeup for coolant contraction only, the RWST alone does not provide sufficient boron to compensate for the positive reactivity added during the cooldown by the moderator coefficient. Using borated water from the RWST (boron concentration =

2500 ppm), a system feed-and-bleed must be conducted to increase boron concentration in the RCS before proceeding with cooldown below 350*F. This initial feed-and-bleed of 4,200 gallons to a boron concentration of approximately 1117 ppm ensures that the RCS boron concentration is maintained above the level required to provide adequate shutdown margin while the plant is cooled from 350*F to 135'F.

C. A plant cooldown is then performed from an average coolant temperature of 350*F to an average temperature of 135*. Makeup water from the RWST (2500 ppm boron) is charged to the RCS as necessary to compensate for coolant contraction during the cooldown.

ABB Combustion Engineering Nuclear Services Page 25 of 167

l t

BORIC ACID CONCENTRATION REDUCTION ErrORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS ,

I D. Alternatively, with the BATS available, makeup may be j supplied by blending boric acid solution from the BATS with demineralized water from the Primary Water Storage -

Tanks. l 2.3.4 Modes 4 and 5 - Cooldown l 3

Makeuo from the RWST f

From Equation 2.0 of Appendix 3 and the conversion factor that is derived in Appendix 4, the initial boric acid mass I in the system can be calculated as follows: l l

1,047 ppm '

12,312 ft3 444.6 ft3 ' "

17 4 8. 34 ppm /wt. %

(

0. 017 97 f 3t /lb, 0. 01912 ft3 /lb,,

k~ 100 - (1047 ppm) /1748.34 ppm /wt%

~ '

or Mu = 4,267.8 lb, boric acid The initial total system mass of 712,662.8 lb, given in Tables 2-5 and 2-6 was obtained as follows:

Minit =

(Initial Boric Acid) + (Initial RCS Water Mass)

+ (Initial RHRS Water Mass) + (Pressurizer Water Mass) I (10,812 ft3 + 1500 f t 3) (444.6 ft 3) j N,,j, = 4 2 67 . 8 lb, + .

(0. 01797 f t /lb,)

3 (0.01912 ft 3/lb,) l I

Mj ,je = 712,66 2. 8 lb, j ABB Combustion Engineering Nuclear Services Page 26 of 167 i

t BORIC ACID CONCENTRATION REDUCTION ZFFORT CEN-602, REY.2 {

TECHNICAL aASES AND OPERATIONAL ANALYSIS j The boron concentration at the end of the feed-and-bleed evolution is determined by an iterative calculation. This j endpoint concentration then permits charging (from the RWST) only as required to compensate for coolant contraction and l

ensures that the final concentration provides the required i shutdown margin at the final temperature of 135'F. !

i i

As indicated above, the initial boron concentration is equal l to 1047 ppm; the mass of boric acid in the system is 4,267.8 ,

lb,; and the total system mass (bot) is equal to 712,662.8 f lb ,. The volume of water and the pressure in the PZR are j 3 '

held constant at 444.6 ft and 350 psia, respectively, and complete mixing is assumed between the PZR and the RCS, as !

r I

discussed previously. !

Equation 9.0 of Appendix 1 was used to determine the time and volume required to complete the initial feed-and-bleed f

evolution. The initial concentration in the RCS is 845 ppm, and the concentration in the RWST is 2500 ppm. ;

i Defining the time constant is defined as follows:

[

l l (m.) m+ (m.) m,+ (m.) m !

T=

! (D)in

)

l l

f 10, 812 f t3 + 1, 500 f t 3' 0.01797 fts/lb, ,

.' 0.1912 444.6 ft3 ftafy3,,

, t (75 gal / min) x (8.329 lb,/ gal)

T = 1134 minutes (at 350*F and 350 psia)

ABB Combustion Engineering Nuclear Services Page 27 of 167

\ - - .. -. .

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL RASES AND OPERATIONAL ANALYSIS The feed-and-bleed equation is:

1 1 C(t) = C, ( e ' ) + C3 (1-e ')

Conducting a feed-and-bleed operation with one charging pump delivering 75 gpm and letdown flow equal to 75 gpm , 56 minutes are required to reach a boron concentration of 1,117 ppm in the RCS. This equates to a feed-and-bleed volume of 4200 gallons.

The volume and concentration of makeup required was then calculated for each 10*F increment of cooldown from 350*F to 135'F, and the results are given in Table 2-5. The BACR Code (reference 4.4) and the following equations were used to perform this analysis:

Shrinkage Mass = (12,312) 1 1 r Vg 9 ,

l I ge Mass RWST Water Volume (@ 70*F) ,

8.3290 lb) gal m i

j Boric Acid Added = (RWST Volume) x 0.12083 lb,/ gal I#) ?

l Total Boric Acid = Initial Boric Acid + Boric Acid Added

Reference 4.5 l Appendix 3 ABB Combustion Engineering Nuclear Services Page 28 of 167 i

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Total System Mass = Initial System Mass + Shrinkage Mass

+ Boric Acid Added Final Concentration , (Total Boric Acid) (100) (1748.34)(3)

Total System Mass Using the methods discussed in Appendix 3 and the conversion factor derived in Appendix 4, the mass of boric acid in the system corresponding to a concentration of 1117 ppm boron is calculated as follows:

W

" 100 C Thus, 1117 . 0 ppm '

12,312 ft3 444.6 ft3 '

174 8.34 ppm / we. % 0.01797 fc3/lb, 0.01912 ft2 /lb,,

( i M" 100 - (1117 . 0 ppm) / (17 4 8. 34 ppm / wt. % )

Nu = 4,550.0 lb, Boric Acid l Knowing the initial mass of boron in the system, the exact concentration and makeup requirements can be calculated for each 10*F increment of a cooldown from 350*F to 135'F.

These values are shown in Table 2-5. Equations used to obtain the values shown in the tables are as follows:

Refer to Appendix 4 l

ABB Combustion Engineering Nuclear Services Page 29 of 167 l l

i BORIC ACID CONCENTRATION REDUCTION EFroRT CEN-602, REY.2 TECENICAL BASES AND OPERATIONAL ANALYSIS P

f \

1 1 Shrinkage Mass = (10,812 + 1,500)

VE L %

Water Volume , hrinkage Mass 8.329 lb) galH' Boric Acid Added = (Water Volume) x (0.12083 lb) gal) (*) !

Total Boric Acid = (Initial Boric Acid) + (Boric Acid Added) a Total System Mass = (Total Initial Mass) + (Shrinkage Mass) ,

+ (Boric Acid Added)

The results of these calculations for system cooldown from 350*F to 135'F are plotted as the actual shutdown curve (curve 2) in Figure 2-3. As can be seen froL. this figure, l shutdown margin greater than that required by the Technical Specifications was maintained throughout the evaluation. A i minimum RWST concentration of 2500 ppm boron is therefore specified in plant Technical Specification 3.1.2.5 to ensure ;

that the proper shutdown margin is maintained. j I

Density of Water at 70*F

See Appendix 3 ABB Combustion Engineering Nuclear Services Page 30 of 167 !

1 l

l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS 2.3.5 Refuelina Water Storace Tank Boration Recuirements

-Modes 4 and 5 Three factors must be considered in determining the RWST water volume required to cool the plant from 350*F to 135'F i while maintaining the required shutdown margin. These factors are as follows:

(1) Initial feed-and-bleed volume, and -

(2) Coolant contraction volume, and l (3) Additional volume for conservatism !

I Therefore, the total required volume is as follows: ;

I i

Volag = Feed-and-Bleed + Shrinkage + Conservatism or Vol,m = 4,200 gal + 867 8.9 gal + 500.0 gal l

?

Volgm = 13,378.9 gal 1ons Round upwards to nearest 100 gallons:

Volym = 13,400 gallons This volume is greater than the volume requirement of 9,690 gallons listed in the current Bases section. Therefore, the :

Bases value will be revised to 13,400 gallons. The ;

compliance value in the Limiting Condition for Operation ;

(LCO) must incorporate the new RWST boration volume; a l ABB Combustion Engineering Nuclear Services Page 31 of 167 I

l

l l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 i TECHNICAL BASES AND OPERATIONAL ANALYSIS volume of 22,182 gallons due to the location of the level tap; a volume of 19,197 gallons as an allowance for level instrumentation error; and 221 gallons roundup, resulting in a volume of 55,000.

2.3.6 Modes 4. 5 and 6 - Cooldown I Blended Makeup. Usina BATS During blending operations, boric acid solution from the BATS via 1(2)-FCV-62-140 is mixed with demineralized water f via 1(2)-FCV-62-143 at the blending tee and then added to i the Volume Control Tank (VCT). With the BATS available as the source of soluble poison during cooldown in Modes 4 and ,

5, the ability to blend and add makeup to the RCS provides a means of minimizing the amount of boric acid solution needed to compensate for coolant shrinkage and to avoid overborating the RCS during the cooldown.

The analysis of a cooldown from 350*F to 135"F using blended I makeup is described in this section. Initial conditions and I assumptions used in this analysis are identical to those !

used in the analysis of cooldown using the RWST and are listed in Table 2-4, and the results are presented in Table 2-6. The concentration out of the blending tee was obtained using the following equation, (Fy x Cy ) (100) (1748.34)

(Fy x C y) + (F,ue x D,)

i ABB Combustion Engineering Nuclear Services Page 32 of 167 '

l l

BORIC ACID CONCENTRATION LEDUCTION EFFORT CEN-602, REY.2 rECHNICAL BASES AND OPERATIONAI, ANALYSIS s 1

where: l

)

C , = boron concentration leaving blended tee in ppa j Fy = flowrate from 1(2)-FCV-62-140 in gpm Cy = concentration in BATS in lb,/ gallon l l

F , = flowrate leaving blending tee in gpm l D, = density of water at 70*F in lb,/ gallon 1748.34 = conversion factor between RCS concentration in weight percent boric acid and RCS concentration in ppm boron. (The derivation of this factor is presented in Appendix 4).

2.3.7 BAT Storace Reauirements - Modes 4.5. and 6 The results of the calculations for system cooldown using i blended makeup in Modes 4 and 5, from 350*F and 350 psia to '

135*F, are given in Table 2-6 and are plotted as the actual !

shutdown curve in Figure 2-4. As shown in the figure, a shutdown margin greater than that required by the Technical Specifications is present throughout the transient.

A minimum BAT concentration of 6120 ppm boron is therefore prescribed in Technical Specification 3.1.2.5 for Modes 4, 5, and 6.

The minimum usable compliance volume to be prescribed in the Technical Specifications is 5,000 gallons. This volume was determined as follows:

\

I l

ABB Combustion Engineering Nuclear Services Page 33 of 167 l

l l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS j l

Makeup volume"# = 4411.2 gallons Additional volume = 500.0 gallons for Conservatism Total = 4911.2 gallons i

Round up to nearest 100 gallons = 5,000 gallons l

l 2.4 BORATED WATER SOURCES - OPERATING (MODES 1, 2, and 3) !

l 2.4.1 Boration Reauirements for Modes 1. 2. and 3 l A shutdown margin 2 1.6 Ak/k must be maintained throughout the cooldown. From this basis, the required RCS boron l concentrations were determined using conservative core j physics parameters and the limiting cooldown scenario .

l outlined in Section 2.2.1.1 above. The results are given in Table 2-7 and are plotted as the Required Shutdown curve in .

Figure 2-5.

i 2.4.2 Assumptions Used in the Modes 1. 2. and 3 Analysis A complete list of assumptions and initial conditions used in calculating the minimum BAT inventory required for Modes ;

1, 2, and 3 is contained in Table 2-8. As stated in Section 2.2.4, all fluid added to the RCS via the loop charging nozzles is assumed to mix completely and instantaneously )

with the RCS and the PZR. In line with this assumption, the l mass of water in the PZR was added to and treated as part of I the total mass of water in the RCS, and this total was then ;

used in calculating system boron concentration.

l Total of values in BAT volume column in Table 2-6 I

ABB Combustion Engineering Nuclear Services Page 34 of 167 l l

l l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS <

l Boron concentration in terms of weight fraction is defined l as follows:

=

N# # *' " A" Y##*"

Baron Concentration Total System Mass l

i where, if complete mixing is assumed between the RCS and the PZR, the total system mass is the sum of the mass of boron in the system, the mass of water in the RCS, and the mass of water in the PZR.

The initial total system mass of 525,254.9 lb, in Tables 2-9 through 2-33 was calculated as follows:

Total Mass = Initial Baron Mass + Initial RCS Water Mass

+ Initial PZR Water Mass or 10,812 ft2 . 444.6 ft2 N* * = 0+

0.021251 ft 2/lbj73 0.0269 8 ft2 /lbj')

Finally, in conformance with Branch Position A.1 of Reference 4.1, the analyses described in Sections 2.4.3 and 2.4.4 were continued through Mode 4, i.e., to an RCS temperature of 200*F.

" Specific volume of compressed water at 547'F and 2250 psia specific volume of saturated water at 2250 paia ABB Combustion Engineering Nuclear Services Page 35 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS 2.4.3 Modes 1. 2. and 3 Analysis Results-Peak Xenon Scenario As stated above, the boration capacity required to reduce the coolant average temperature to 200*F or below is f determined by the requirement for providing a shutdown j margin of at least 1.6% Ak/k, after xenon decay and a plant j cooldown to 200*F from normal operating conditions.

Assuming the initial conditions outlined in Table 2-8, a plant cooldown to an RCS average temperature of 200*F is 1 conducted, starting from an initial RCS average temperature t

of 547'F.

Charging to the RCS is performed only as necessary to ec=pensate for coolant contraction. Initially, the charging pumps will take suction from the BAT. When the usable inventory of the BAT has been exhausted, the charging pump suction is aligned to the RWST for the remainder of the cooldown. When the RCS temperature has been decreased to a temperature greater than 400*F, a feed-and-bleed operation will be performed to further increase boron concentration.

The calculated RCS boron concentration versus temperature l for plant cooldown and depressurization from 547'F and 2250 psia to 200*F and 350 psia, with a boric acid concentration of 3.5 weight percent in the BAT and a boron concentration in the RWST of 2500 ppm, is presented in Table 2-9. The required concentration as a function of temperature is given in Table 2-7 and is plotted on Figure 2-5 as the Required Concentration curve.

l l

The results of these calculations are plotted as the Actual Concentration curve in Figure 2-5. (The exact temperature ABB Combustion Engineering Nuclear Services Page 36 of 167

I i

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 j TECHNICAL BASES AND OPERATIONAL ANALYSIS i at which the charging pump suction was transferred from the j BATS to the RWST was determined using an iterative calculation, as was the duration of the feed-and-bleed; in this way, the smallest BAT volume necessary to maintain the required shutdown margin was calculated for the given set of tank concentrations). Note that at all times, the RCS boron concentration is greater than that necessary for the

required shutdown margin during the cooldown.

4 Also note in Figure 2-2 that the required boron concentration increases at an average coolant temperature of 200*F to provide to provide adequate shutdown margin during xenon decay. With the coolant at 200'F, the final concentration required in the RCS is 1158.0 ppm boron.

Using the scenario outlined above, the final system concentration will always be greater than this amount. A detailed parametric analysis was performed for the Modes 1, 2, and 3 Technical Specification (Specification 3.1.2.6).

In this study, BAT concentration was varied from 6120 ppm boron (3.5 weight percent boric acid) to 6990 ppm boron (4.0 weight percent boric acid) and RWST concentration was varied from 2500 ppm boron to 2700 ppm boron. The results are shown in Pables 2-9 through 2-33. The following equations were used to obtain the values in these tables:

1 1 Shrinkage Mass = (10,812)

V V s t 4 \

l 1

Shrinkage Mass l BAT Vol . ,

(8.3290lb/ gal)W l

l

Density of Water at 70*F ABB Combustion Engineering Nuclear Services Page 37 of 167

i 1

4 t

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602,. REY.2 TscaNICAL-BASES AND OPERATIONAL ANALYSIS ;

hrinkage Mass RWST Vol ,

(8.3290 lbggal) i i

i Boric Acid Added = (BAT Vol) x (Mass of Boric Acid / gal) h*)

I or l

1 Boric Acid Added = (RWST Vol) x (Mass of Boric Acid / gal) i i

r Total Boric Acid =

(Initial Boric Acid) + (Boric Acid Added) i Total System Mass = (RCS Water Mass) + (PZR Water Mass)*

+ (Total boric acid)

Final Concentration , (Total Boric Acid) (100) (1748.34} ;

(Total System Mass)

C( t) = RCS Concentration after feed-and-bleed ;

t C( c) = C, e-*/' + Cj , (1-e-e/s)

I l

Ca = Concentration at 400*F prior to Feed-and-Bleed i l C3 , = RWST Concentration !

I See Appendix 3 l

PER Water Mass = (444.6 f t') + v,at indicated P.- l I

ABB Combustion Engineering Nuclear Services Page 38 of 167 )

i

.i I

I - -

I t l !

I BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 ;

TECHNICAL BASES AND OPERATIONAL ANALYSIS t

t = Time = RWST Volume / 75 gpm i

T = Feed-and-B1eed Time Constant at 400*F = ' '.'*'**

N,.

10,812 ft 3 . 444.6 ft3

, t 0.018415 ft 3/lb; t 0.02698 ft 3/lb; l

(75 gpm) (8.329 lbg gal) !

I ;

T = 966.2767 minutes f

C H*

Ha = Total Boric Acid after F-and-B = 100 - C J C(t) }

10,812 ft3 ',# 444.6 ft3 y , i1748.34i < 0.018415 ft 3 /lb; i 0.02698ft 3/lb; C IUI 100 - ([1748.34 1 l

Note that the value of the total system mass at any I I

temperature and pressure in Tables 2-9 through 2-33 may be obtained as follows:

Meae = RCS Water Mass + PZR Water Mass + Total Boric Acid Mass + RHRS Water Mass (when on RHRS)

For example, the Total System Mass at 200'F and 350 psia in Table 2-9 is as follows:

ABB Combustion Engineering Nuclear Services Page 39 of 167 l

e 1

i i

i

] BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2

TECHNICAL Basts AND OPERATIONAL ANALYSIS l l

! =

10,812 ft 3 444.6 ft3 1500 f9 M* * . .

0.01662 fc3/lbji33 0.01912 ft /lbji33 3 0.01662 ft3/lb,

+ 5, 3 8 6 . 7 lb, i

l , or l

l N,,, = 769,434. 0 lb, 4

The calculated concentration values given in Tables 2-9

)

through 2-33 were compared to the values in Table 2-7, which shows the concentrations which must be maintained at all '

temperatures during cooldown through the range from 547'F to 200'F. In each case, the actual system boron concentration '

was greater than necessary for the required shutdown margin. 1 To set the minimum Technical specification BAT volume corresponding to the various BAT and RWST concentrations, the makeup volumes from Table 2-9 through Table 2-33 were combined into Table 2-34. To establish the required volumes which must be stored in the BATS, these boration volumes were adjusted by adding 500 gallons for conservatism and rounding the result upwards to the nearest 50 gallons. In some cases, 50 more gallons were added to result in the same values as Revision 1.

These results are given in Table 2-35 and are illustrated in Figure 2-6, which shows the boration volumes, and in Figure 2-7, which shows the required volume which must be maintained in the BAT.

[ v, of cornpressed water 9 200*F and 350 psia I v,of saturated water 9 350 psia l

ABB Combustion Engineering Nuclear Services Page 40 of 167 l

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

I l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANAI.YSIS 2.4.4 Modes 1, 2, and 3 Analysis Results -

Xenon Free Scenario The initial conditions for this scenario are listed in Table 2-36. Note that the plant is held at the hot, zero power temperature of 547'F. The required boron concentrations used for this scenario were provided by TVA and are shown in Table 2-37 and as the Required Concentration curve in Figure 2-8.

Prior to commencing cooldown, a feed-and-bleed operation is performed to increase boron concentration in the RCS to 579 ppm, using the BAT. The RCS is then cooled to 500'F, with l makeup for contraction provided by the BAT and RWST. At 500*F, a feed-and-bleed operation is performed to increase boron concentration to the level from which the required shutdown margin can be maintained during the cooldown to 200*F, with makeup for coolant contraction taken from the RWST.

l l

The feed-and-bleed equations from Appendix 1 were used to determine the volume required from the BATS for several concentrations.

1. The feed-and-bleed time constant r is determined as l follows:

l

, , Mass of Water in RCS + Mass of Water in P2R Mass Flow Rate l

l ABB Combustion Engineering Nuclear Services Page 41 of 167

l I 1

l l

l monIc AcIn concamTRATIon mapucTIow arroRT CEN-602, REY.2 l t

TscswIcAL BASES AND OPERATIONAL ANALYSIS l

1 10,812 fc3 444.6 ft3 '

'8 ,

t 0.021251 ft3/lb,D'8 ; ,0.02698 ft2 /lb ,

(75 ppm) (8.329 lb / gallon) l i l

T,3 = 84 0. 9 min l l l

i l

2. The feed-and-bleed equation is solved for time:

l l

f C ( c) = Ca e-*/' + Cf , (1 - e-*/')

i Since the initial concentration Co = 0 ppa, this reduces to C (c) = C3 (1 - e-t/')

l l

l C (t) , y _ g .ef, ,

C, g

I e - */* = 1 - CU L

Cin ; ;

i l

In e ~*/' = In 1- CI UI A la s, c, of water at 2250 psia and 547 ABB Combustion Engineering Nuclear Services Page 42 of 167 i

BORIC ACID CONCFJfTRATION REDUCTION EFFORT CEN-602, REY.2 TBCENICAL BASES AND OPERATIONAL ANALYSIS CI UI

-( t/T) = In 1- Cla i 3, C = -r ln 1- (U s C,,,

1

3. With a known value of C(t) = 579 ppa, the time required to reach this concentration can be calculated for a range of BAT concentrations as Cg. The BAT volume required is determined by multiplying the charging flow rate of 75 gpa by the calculated time. The results of these calculations are given in Table 2-38.

4. The calculated BAT volumes are then inserted into the boration tables. With an initial boron concentration l of 579 ppa at the hot, zero power conditions, the mass

! of boric acid in the RCS is as follows:

l I

' 579 ppm i' 10,812 ft3 , 444.6 ft3 '

( L 1748.34 wt%/ ppm 1 , O. 021251 ft3 /lb, .0269 8 ft3 /lb,,

7 100 - ' ###

t 1748.34wt%/ ppm \ 4 l

Nu = 17 4 5. 3 lb, The initial system mass is then equal to:

l ABB Combustion Engineering Nuclear Services Page 43 of 167 l

h . - .,-

l I

i I

1 BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 i TECENICAL BASES AND OPERATIONAL ANALYSIS ]

l

\ My = Nassa + Mass, + Mu 10,812 fc3 i ,' 444.6 fc3 '

1745,3 y3" Nm= 0.021251 fc2/lb,, ,0.0269 8 fc8/lb,,

Nm = 527,000.2 lb, Using these initial values, the plant cooldown from 547*F to 500*F is conducted. Charging to the RCS from the BAT is performed as necessary to compensate for coolant contraction. Initially, the charging pump suction will be aligned to the BAT; when the usable contents of the BAT have been exhausted, the charging pump suction will be realigned to the RWST for the ;

remainder of the cooldown.

i

5. At 500*F, a feed-and-bleed is performed using borated water from the RWST. The volume of water charged to the RCS in this operation is dependent on the boron concentration in the RWST.

6. Following this feed-and-bleed at 500*F, the plant is :

cooled to 200*F, charging from the RWST as necessary to compensate for coolant contraction.

7. The volume of borated water required from the BAT and RWST during the cooldown to 500*F and from the RWST during the cooldown and depressurization from 500*F at 2250 psia to 200*F at 350 psia was calculated in the manner described in section 2.4.3 of this report. The ABB Combustion Engineering Nuclear Services Page 44 of 167

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

I i

l l

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 I l TECENICAL BASES AND OPERATIONAL ANALYSIS t results of these calculations are given in Table 2-39 l through Table 2-63. !

8. From an initial concentration in the RCS of 579 ppa, l the results of a cooldown following, feed-and-bleed fron l the BATS at a concentration of 4.0 weight percent and j an RWST concentration of 2500 ppa are shown in Table 2- l t

63 and are plotted in Figure 2-8 as the Actual' Concentration curve. The exact temperature at which the charging pump suction was realigned from the BAT to ;

the RWST was determined by an iterative calculation, to l

establish the minimum BAT volume needed to maintain the i required shutdown for each pair of_ tank concentrations.

Note that at all times during the~transivent, the RCS ,

boron concentration is greater than that necessary to l maintain the required shutdown margin.. l i

The following equations were used to obtain the~ values in l

Tables 2-39 through 2-63: I t

1 Shrinkage Mass = (10,812) --

g Vr V> i I i

BAT Vol. , Shrinkage Mass l (8.3290 lbggal) !

brinkage Mass ;

RwST vol ,

(8.3290 lbggal)

ABB Combustion Engineering Nuclear Services Page 45 of 167

- - - =- - _ . . . . - _ . . . - - _ - - - :. - . _ -

BORIC ACID conscENTRATIcer REDUCTION EFFORT CEN-602, REY.2 :

TECENICAL BASES AND OPERATIONAL ANALYSIS !

l Boric Acid Added = (BAT Vol) x (Mass of Boric Acid / gal) or ;

Boric Acid Added = (RWST Vol) x (Mass of Boric Acid / gal) l Total Boric Acid =

(Initial Boric Acid) + (Boric Acid Added)

Total System Mass = (RCS Water Mass) + (PER Water Mass)

+ (Total boric acid)

Final Concentration , ( otal Boric Acid) (100) (1748.34)

(Total System Mass) '

i C(C) = RCS Concentration after feed-and-bleed C(c) = C, e-*/' + Cj, (1-e-c/s) l l

Ca = Concentration at 500*F prior to Feed-and-Bleed l l t = Time = RWST Volume / 75 gpm s = Feed-and-Bleed Time Constant at 500*F = ****

H, ABB Combustion Engineering Nuclear Services Page 46 of 167 i

1 i

i t

BORIC ACID CoNCE3fTRATION REDUCTION EFFORT CEN-602, REY.2 TsCaNICAL nasse AND OPERATIONAL ANALYSIS i

[

t I

10,812 ft3 ' # '

. 444.6 ft3 .

, t 0.02009 ft 3/lb; t 0.02698 ft 3/lb; i (75 gpm) (8.329 lb,/ gal)

I T = 8 87 . 913 minutes ,

[

C M, '

My = Total Boric Acid after F-and-B = l 100 - C i i l

I f C(t) 10,812 ft3 444.6 ft3 1748.34;}

l _ i t 0.02009 ft 3/lb; 0.02698ft 3/lb; ;

"~ t 100 j! C (t) 1 1 l

l 1 1748.34j I

)

Note that the value of the total system mass at any !

i temperature and pressure in Tables 2-39 through Table 2-63 may be obtained as follows: I i

M eat = RCS Water Mass + PZR Water Mass + Total Boric Acid Mass + RERS Water Mass (when on RHRS)

The calculated concentrations shown in Tables 2-39 through 2-63 were co= pared to the values listed in Table 2-37, which shows the concentrations which must be maintained at all temperatures during the xenon-free cooldown from 547'F to ABB Combustion Engineering Nuclear Services- Page 47 of 167

_ _ _ . , ,, . _ _ , . . _ , _l_,. ]

i BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS 200*F. In every case, the actual boron concentration in the system is greater than that necessary to provide the required shutdown margin.

The BAT volumes required for the xenon-free scenario shown in Tables 2-39 through 2-63 were combined into Table 2-64.

These values were then compared to the results obtained in the peak xenon scenario (Table 2-34). In all cases, the values for the xenon-free scenario are lower than those for the peak xenon scenario. Therefore, since the volumes required for the peak xenon scenario are greater, the peak xenon values were used to establish the Technical Specification for BAT storage requirements.

2.4.5 Simolification Used Followina RHRS Initiation The results of the analysis of cooldown and depressurization are given in Tables 2-9 through 2-33 and 2-39 through 2-63.

In this procedure, the RHRS must be aligned to the RCS at an RCS temperature and pressure of approximately 350*F and 350 psia. Following this alignment, the volume and mass of the system that the operator must consider during any subsequent cooldown will be increased by the volume and mass of fluid present in the RHRS. Further, the total mass of boron in the system will also be increased by the amount of boron in the RHRS prior to alignment. For this analysis, a value of 3

1500 ft was used for the RHRS volume. In the tables in Section 2.4.3 and 2.4.4, this RHRS volume is added when the system reaches 350*F and 350 psia. The boron concentration in the RHRS is assumed to be equal to that in the RCS at the time the RHRS is brought into service.

ABB Combustion Engineering Nuclear Services Page 48 of 167

l l

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS I 2.5 BORATION SYSTEMS - BASES 1

r The BASES section of the Technical Specifications was developed to demonstrate the capability of the boration system to maintain adequate shutdown margin from all operating conditions. The following change to Bases Section j 3/4.1.2 of the plant Technical Specifications is proposed:

i "The boration capability of either flow path is sufficient l 1

to provide a SHUTDOWN MARGIN from expected operating ;

conditions of 1.6% Ak/k after xenon decay and cooldown to 200*F. The maximum boration capability requirement occurs at EOL from full power equilibrium xenon conditions and I

requires borated water from a boric acid tank in accordance with Figure 3.1.2.6, plus appropriate makeup from the common boric acid tank or through batching, or a minimum of 26,000 gallons of 2500 ppm borated water from the refueling water storage tank. With the refueling water storage tank as the only borated water source, a minimum of 57,000 gallons of 2500 ppm borated water is required."

Note that the bases were derived for a cooldown-with-letdown scenario in which two scenarios are evaluated:

a. The required volume from the RWST alone, or

b. The required volume from the RWST, with the smallest BAT volume being used prior to using the RWST.

This is a cooldown beyond the requirements of BTP 5-1.

i ABB Combustion Engineering Nuclear Services Page 49 of 167

l

! l I

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-502, REY.2 '

TECHNICAL BASES AND OPERATIONAL ANALYSIS i 2.5.1 Derivation of the 57.000 Gallon Volume (RWST) l The required RWST volume of 57,000 gallons was determined as follows:

l A. Calculations were performed for a plant cooldown from 547'F and 2250 psia to approximately 350*F and 350 psia, compensating for coolant contraction by charging <

of 70*F borated water from the RWST, at a concentration :

of 2500 ppm boron. The concentration in the RCS is I

initially at 0 ppm.

B. The RHRS is aligned to the RCS when the RCS reaches a temperature and pressure of 350*F and 350 psia. The 3

RHRS volume has been determined to be 1500 ft , and, at the time of shutdown cooling initiation, the concentration in the RHRS is assumed to be equal to the concentration in the RCS. Typically, the RHRS will be l at normal refueling concentration (12500 ppm), but the lower value was chosen for added conservatism.

1 C. Cooldown of the system is continued from 350*F and 350 psia to 200*F and 350 psia, using borated water from the RWST (2500 ppm and 70*F)as necessary to makeup for l contraction. l l

D. Using the methodology described in Appendix 1, a feed- !

and-bleed calculation is performed until the boron concentration in the RCS reaches a value not less than 1212 ppm to ensure that an adequate shutdown margin is i maintained.

I ABB Combustion Engineering Nuclear Services Page 50 of 167 l

1

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS E. The volumes calculated in paragraphs A through D are summed, and the total is then rounded up to the nearest 1000 gallons. '

The plant cooldown using water from the RWST alone as discussed above results in a minimum required RWST water volume of 57,000 gallons. This value is contained in the '

bases for Technical Specification 3/4.1.2 and Table 2-65. '

2.5.2 Derivation of the 26.000 Gallon RWST Volume Recuired when the Smallest BAT Volume is Used i

The RWST volume used after the BAT is used per Technical i specification 3.1.2.6 consists of the following parts:

l A. Calculations were performed for a plant cooldown from [

547'F and 2250 psia to approximately 400*F and 2250 ,

psia, compensating for coolant contraction by charging first from the BAT until empty and then with 70'F '

l borated water from the RWST, at a concentration of 2500 ;

ppm boron. The concentration in the RCS is initially at 0 ppm.

B. A 13,500 gallon feed-and-bleed is conducted using the RWST at 2500 ppm and 70*F.

l C. The cooldown of the system is continued from 400*F and 2250 psia to 350*F and'350 psia, using borated water from the RWST as necessary to makeup for contraction.

D. The RHRS is aligned to the RCS when the RCS reaches a ;

temperature and pressure of 350'F and 350 psia. As noted, the RHRS volume is 1500 cubic feet, and, at the ABB Combustion Engineering Nuclear Services Page 51 of 167 1

I BORIC ACID conM TIoM REDUCTIoK EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS time of initiation, the concentration in the RHRS is !

assumed to be equal to the concentration in the RCS.

Normally, the RHRS will be at refueling concentration l (22500 ppm), but tha lower value was chosen for conservatism.

E. Cooldown of the system is continued from 350*F and 350 psia to 200*F and 350 psia, using borated water from

( the RWST (2500 ppm and 70*F) as necessary to makeup for

! contraction. l l !

l The plant cooldown using water from the BAT and then the

( RWST as discussed above results in a minimum required RWST water volume of 26,000 gallons. This value is contained in the bases for Technical Specification 3/4.1.2 and for Table 2-66.

2.6 ACTION STATEMENTS ON FLOW REQUIREMENTS The current Sequoyah Technical Specifications contain action statements which require boration from the BATS. Since the concentration of boron in the BATS will be reduced, an increase in the minimum flow rate is required. The increased flow rate is applicable to Technical Specifications 3.1.1.1, 3.1.1.2, 3.9.1, and 3.10.1, and Surveillance Requirement 4.1.2.2.d.

The revised Action Statement is as follows:

" Initiate and continue boration at greater than or equal to 35 gpm of a solution containing boric acid at a concentration greater than or equal to 6,120 ppm boron or its equivalent."

ABB Combustion Engineering Nuclear Services Page 52 of 167

I t I

l i noEIc AcIn conczNTRATION REDUCTION RFFoRT CEN-602, REY.2 l TscuMIcAL nasES AND OPERATIONAL ANALYSIS This boration capability uses the current minimum boric acid concentration in the BAT. The specified flow rate is 3 limited by the indicating range of the flow measurement ;

instrumentation in the boric acid line to the blending tee, !

which provides an alternate flow path for emergency 7 boration. i To determine the new requirements, the amount of boron added to the system under the existing requirements must be evaluated. Using the methods and equations in Appendix 3, ;

the mass of boric acid per gallon of solution is as follows: )

i l

C x M, i Mu= 100 - C 1

l where: C = Concentration in weight percent boric acid and: %= 8.13985 lb,/ gallon at 165'F (Reference 4.4) 1 Therefore:

0,000

[1748.34,h 8.139 85 Nu= 1 100 - 20,000\ ,

(1748.34 1 '

1 and Hu = 1.051431b) gallon ABB Combustion Engineering Nuclear Services Page 53 of 167 l - .

BORIC ACID oONCENTRATION REDUCTION EFFORT CEN-502, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS '

With a boron concentration of 20,000 ppm and at a flow rate j of 10 gpm, 10.1543 pounds of boric acid are added to the system per minute.

At the new minimum boric acid concentration of 6120 ppm of l boron, one gallon of solution contains 0.30209 pounds of l boric acid. The new flow requirement is determined by dividing the current minimum boric acid injection rate by the new minimum concentration, as follows:

nute Flow Ra te(*) , 10.514 0.30209

/

lb/ gal l

or l i

l l

Flow Ra te y = 34.8 gpm '

which is rounded upwards to Flow Rate, = 35gpm i

l Therefore, the new action statement should read as follows:

" Initiate and continue boration at greater than or equal to 35 gpm of a solution containing greater than or equal to 6120 ppm boron or its equivalent."

ABB Combustion Engineering Nuclear Services Page 54 of 167 l l

I I

i nomIc ACID coKcsNTRATICK REDUCTION EFFORT CEN-602, REY.2 -

TBCENICAL BASES AND OPERATIONAL ANALYSIS l This new action statement is applicable to Technical l Specifications 3.1.1.1, 3.1.1.2, 3.9.1,'and 3.10.1, and f r Surveillance Requirement 4.1.2.2.d.

r l

?

l f

I I

i :

( :

! i i

-)

i i

l I

i i

i l

o

{

i l

l ABB Combustion Engineering Nuclear Services Page 55 of 167 -

i I

. - .~

, ._._;.._. _. _ . . . , , _ . - , , . _,,,__---,.,L.,,,,,

i I

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS i

Table 2-1 Boric Acid Solubility in Water"'

Temperature H,BO (y) (wt.%)

32.0 2.52 41.0 2.98 50.0 3.49 59.0 4.08 1

68.0 4.72 77.0 5.46 l 86.0 6.23

95.0 7.12 1

104.0 8.08 113.0 9.12 122.0 10.27 131.0 11.55 140.0 12.97 149.0 14.42 158.0 15.75 167.0 17.41 176.0 19.10 l

Reference 4.2 ABB Combustion Engineering Nuclear Services Page 56 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Table 2-2 Time Intervals for Determining an Effective RCS Cooldown Rate Initial Hot Standby Hold PeriodI " 4.00 hours0 days 0 hours 0 weeks 0 months Plant Cooldown from 547 F to 400 F(2) 5.88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months Feed-and-Bleed Time 4.00 hours0 days 0 hours 0 weeks 0 months Plant Cooldown from 400*F to 300*F 4.00 hours0 days 0 hours 0 weeks 0 months Steam Generator Soak at Temperature 8.00 hours0 days 0 hours 0 weeks 0 months Between 310*F and 290*F Plant Cooldown from 300 F to 200*F (2) 4.00 hours0 days 0 hours 0 weeks 0 months Additional Conservatism 4.82 hours9.490741e-4 days 0.0228 hours 1.35582e-4 weeks 3.1201e-5 months

! Total 34.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months 4 hours per requirements of BTP RSB 5-1

An average cooldown rate of 25'F/hr is assumed ABB Combustion Engineering Nuclear Services Page 57 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Table 2-3 Required Boron Concentration for a Plant Cooldown (Refer to Appendix 5)

Temperature Concentration Concentration

(* F) ppm Boron (ppm Boron)

Xenon Free Limiting Cooldown (Peak Xenon) 547 579 0 500 737 295 450 868 519 400 970 703 350 1047 850 300 1109 966 250 1163 1060 200 1212 1140 200 1158 1158 190 1168 1168 180 1178 1178 170 1188 1188 160 1198 1198 150 1208 1208 135 1223 1223 ABB Combustion Engineering Nuclear Services Page 58 of 167 1

l l l

! I I

l BORIC ACID oONCENTRATIoK REDUCTION EFFORT CEN-602, REV.2 j TECHNICAL BASES AND OPERATIONAL ANALYSIS l

l Table 2-4 l

Initial Conditions and Assumptions Used in the Modes 4,5 and 6 Calculation

a. Reactor Coolant System Volume 10,812 ft 3

b. Reactor Coolant System Pressure 350 psia 3

! c. Pressurizer Volume (8 0% Power Level) 444.6 ft I

l d. Pressurizer is at Saturation -----

e. Reactor Coolant System Leakage O .

l f. Boration Source Concentration l Refueling Water Tank Storage (RWST) 2500 ppm boron Boric Acid Tank (BAT) 3.5% Boric Acid

g. Boration Source Temperature 70 F

h. Initial RCS Concentration 1047 ppm boron i

1. Initial Pressurizer Concentration 1047 ppm boron

j. Complete and Instantaneous Mixing ----- A Between Pressurizer and RCS l

k. Constant PZR Level Maintained, Charging -----

l to Compensate for Coolant Contraction '

i

1. Total System Volume (RCS+RHRS+PZR) 12,756.6 ft 3 l l

l l

l Refer to discussion in Section 2.2.4 Refer to discussion in Section 2.3.2 I

l ABB Combustion Engineering Nuclear Services Page 59 of 167 l

BORIC AClD CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-5 SEQUOYAH - MODES 4 & 5 COOLDOWN - 350*F TO 135'F FEED-AND-BLEED USING RWST @ 2500 ppm BORON AVG.SYS. TEMP. PZR SPECIFIC VOLUM E SHRINKAGE RWST VOL B/A TOTAL TOTAL RCS TEMP. PRESS. cu.ft./lbm MASS @ 70*F ADDED B/A SYS. MASS CONC.

Ti('F) Tf(*F) (psia) Vi' VI (Ibm) (gallons) (Ibm) (Ibm) (Ibm) (ppm Borm)

! 0.0 350 350 350 0.01797 0.01797 0.0 0.0 4,267.8 712462.8 1047.0

!- FEED-AND-BLEED FROM RWST(OALLONS) 4200 l 350 350 350 0.01797 0.01797 0.0 0.0 0.0 4,555.0 712p50.1 1,117.0

. 350 340 350 0.01797 0.01785 4,606.0 553.0 66.8 4,621.8 717422.9 1,126.0

340 330 350 0.01785 0.01774 4,276.9 513.5 62.0 4,683.9 721761.8 1,1343 330 320 350 0.01774 0.01763 4,330 3 519.9 62.8 4,746.7 726,354.9 1,142.5 320 310 350 0.01763 0.01753 3,983.8 4783 57.8 4,804.5 730.3 %.5 1,150.0 313 300 350 'O.01753 0.01743 4,029.5 4832 58.5 4,862.9 1,157.6 f- 734A84.4 l 300 290 350 0.01743 0.01734 3,666.3 440.2 53.2 -4,916.1 738,203.9 1,1643 290 280 350 0.01734 0.01724 4,118.5 494.5 59.7 4.975.9 742,382.1 1,171.8 280 270 350 0.01724 0.01715 3,747.7 450A 54.4 5,030.2 746,184 3 1,178.6 l 270 260 350 0.01715 0.01707 3,364.5 404D 48.8 5,079.0 749,597.6 1,184.6 260 250 350 0.01707 0.01699 3,3%.2 407E 49.3 5,128 3 753p43.0 1,190.6 250 240 350 0.01699 0.01691 3,428.3 4114 49.7 5,178.0 756,521.1 1,1%.7 240 230 350 0.01691 0.01683 3,440.9 415.5 50.2 5,228.3 760p32.2 1,202.7 230 220 350 0.01683 0.01676 3,055.4 3662 44 3 5,272.6 763,131.9 1,208.0

220 210 350 0.01676 0.01669 3,081.0 369.9 44.7 5,3173 766,257.6 1,213.2 s

210 200 -350 0.01669 0.01662 3,167.0 373D 45.1 5,362 3 769A09.7 1,218.5 200 190 350 0.01662 0.01655 3,1333 376.2 45.5 5,407.8 772,588.4 1,223.8 190 180 350 0.01655 0.01649 2,706.8 325h 39.3 5,447.1 775,334.5 1,228 3 l

180 170 350 0.01649 0.01643 2,726.6 327.4 39.6 5,486.6 778,100.7 1,232.8 l

170 -160 350 0.01643 0.01638 2,287.4 2744 33.2 5,519.8 780A213 1,236.6 l 160 150 350 0.01638 0.01632 2,763.4 3312 40.1 5,559.9 783,224.8 1,241.1 150 135 350 0.01632 0.01626 3,016.7 362.2 43.8 5,603.7 786,2853 1,246.0

} 8,678.9 GALLONS SHRINKAGE i + 4200.0 FEED AND BLEED VOLUME l TOTAL RWSTVOLUME = 12,878.9 TOTAL l SOXFM456

]

1

ABB Combustion Engineering Nuclear Services Page 60 of167 4

1.__._._ . . _ . . _ _. _._..____.__.__._-._.____m_.___ . - _ _ - _ _ _ _ _ _ _ _ _ _ . ..

__-_____--________-____._.._*-_____m -

- -m.~.----+--#,.r-.. . - ~ - ._._m - -

l BORIC ACID CONCENTRAllON REDUCTION EFFORT i TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-6 .

SEQUOYAH - MODES 4 & 5 COOLDOWN - 3507 TO 135'F

BLENDED MAKEUP - BAT @ 3.5 wt% BORIC ACID AVO.SYS. PZR SPECIFIC VOLUME SHRIN KAGE BLEND BATVOL PURE B/A TOTAL TOTAL RCS TEMP. PRESS. cu.ftJIbm MASS RATIO @ 70*F H2O ADDED B/A SYS. MASS CONC Ti(*F) Tf(*F) (psia) VI Vf (Ibm) (galles) (gallas) (Ibm) (Ibm) (Ibm) [ ppm borm) i 350 350 350 0.01797 0.01797 0.0 0 0.0 0.0 0.0 4,267.8 712462.8 1,047.0 j 350 340 350 0.01797 0.01785 4,606.0 0 553D 0.0 167.1 4,434.9 717A35.9 1,080.7 340 330 350 0.01785 0.01774 4,276.9 0 513.5 0.0 155.1 4,590.0 721A67.9 1,111.7 330 320 350 0.01774 0.01763 4,3303 0 519.9 0.0 157.1 4,747.0 726,355.3 1,142.6

, 320 310 350 0.01763 0.01753 3,983.8 0 4783 0.0 144.5 4,891.5 730,483.5 1,170.7 310 300 350 0.01753 0.01743 4,029.5 0 4833 0.0 146.1 5,037.7 734459.2 1,196.9 300 290 350 0.01743 0.01734 3,666 3 0 440.2 0.0 133A 5,170.7 738A58.4 1,224.2

290 280 350 0.01734 0.01724 4,118.5 3 1234 370.9 373 5,208.0 7424143 1,226.1 280 270 350 0.01724 0.01715 3,747.7 3 112.5 337.5 34.0 5,242.0 746,396.0 1,227.9

270 260 350 0.01715 0.01707 3,364.5 3 101A 303A 30.5 5,272.5 749,791.0 1,229.4

, 260 250 350 0.01707 0.01699 3,396.2 3 101.9 305A 30.8 5,3033 753,218.0 1,231.0

{ 250 240 350 0.01699 0.01691 3,428 3 3 1023 308.7 31.1 5,334.4 756477.4 1,232.5 240 350 0.01683 3,460.9 230 0.01691 3 103S 3114 31.4 5,365E 760,169.7 1.234.1 i 230 220 350 0.01683 0.01676 3,055.4 3 91.7 275.1 27.7 5,393.5 763,252.8 1,235.4 l 220 210 350 0.01676 0.01669 3,081.0 3 92.5 277.4 27.9 5,421.4 766,361.8 1,236.8 i 210 200 350 0.01669 0.01662 3,1M.0 3 93.3 2792 28.2 5,449.6 769/96.9 1,238.2 200 190 350 0.01662 0.01655 3,1333 3 94.0 282.1 28.4 5,478.0 772458.6 1,239.5

! 190 180 350 0.01655 0.01649 2,706.8 3 81.2 243.7 24.5 5,502.5 775,390.0 1,2A0.7

!. 180 170 350 0.01649 0.01643 2,726.6 3 81E 245.5 24.7 5,527.2 778,1413 1,241.9 170 160 350 0.01643 0.01638 2,2M.4 3 68.7 206D f 20.7 5,548.0 780A49.5 1,242.8 j 160 150 350 0.01638 0.01632 2,763.4 3 82.9 248A 25.1 5,573.0 783237.9 1,244.0

} 150 135 350 0.01632 0.01626 3,016.7 3 90.5 2714 27.4 5,600.4 786,282.0 1,245 3 t

l TOTAL BAT VOLUME = 4,411.2 GALLONS l SQXFM456 i ABB Cornbustion Engineering Nuclear Services Page 61 of167 i

i L.-.__.-_.-__.--_-_-__.__--__--.__---____ ---n.. - _ _ - . . . - - . . , _ . . ., .. . , , _ . . . - . . . - - ~ ..- - - ~- . _.-_-- _ ,

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Table 2-7 Required Boron Concentration for a Cooldown From 547'F to 135'F Peak Xenon Scenario Temperature Concentration Temperature Concentration

F (ppm boron) *F (ppm boron) umummmmmmmmmmmmmmmme summmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm m mu 547 0.0 410 666.2 540 43.9 400 703.0 535 75.3 390 732.4 520 169.5 385 747.1 510 232.2 380 761.8 500 295.0 370 791.2 490 339.8 360 820.6 480 384.6 350 850.0 470 429.4 300 966.0 460 474.2 250 1060.0 450 519.0 200 1140.0 440 555.8 200 1158.0*

430 592.6 135 1223.0 420 629.4 Concentration Requirement for 1.0% Ak/k, xenon free after borating from peak xenon case.

ABB Combustion EngineerinD Nuclear Services Page 62 of 167

BORIC ACID 00NCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Table 2-8 Initial Conditions and Assumptions Used l In the Modes 1,2, and 3 Calculation l i

3

a. Reactor Coolant System Volume 10,812 ft .

I

b. Reactor Coolant System Pressure 2250 psia l j

3

c. Pressurizer Volume (6 0% Power Level) 444.6 ft

d. Pressurizer is at Saturation

e. Reactor Coolant System Leakage 0

f. RCS Depresurization Performed as Shown -----

in Tables 2-9 through 2-33

g. Initial RCS Concentration 0 ppm boron ,

h. Initial PZR Concentration 0 ppm boron l 1. Complete and Instantaneous Mixing -----

l Between Pressurizer and RCS l j. Constant PZR Level Maintained, Charging -----

to Compensate for Coolant Contraction l

l k. Boron Concentration in RCS equal to -----

Concentration in RHRS at Time of Residual Heat Removal Initiation

1. Boration Source Temperature -----

Refueling Water Storage Tank (RWST) 70*F Boric Acid Tank (BAT) 70'F ABB Combustion Engineering Nuclear Services Page 63 of 167 l

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

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV. 2 TABLE 2-9 SEQUOYAH PLANT COOLDOWN FROM 547 F TO 200 F BAT AT3.50 wt% BORIC ACID: RWSr AT 2500 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRIN KAOE BAT VOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRESS. MASS @ 70*F @ 70*F ADDED B/A MASS CONC (cu.ft./lbm)

Ti(*F) Tr('F) (psla) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (Ibm) (ppm borm) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5684 0.0 171E 1713 530,162.9 56.6 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 4623 634.1 543,372.4 204D 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 4323 1,066.4 555,723.5 335.5 500 480 2250 0.02009 0.01 % 9 10,933.0 1,3 12.6 0.0 396.5 1,462.9 567p53.0 451.1 480 450 2250 0.01969 0.01916 15,336.7 1,841.4 0.0 5563 2,019.2 582p46.0 6054 450 412 2250 0.01916 0.01857 17,656.1 2,119.8 0.0 640.4 2,659.6 601,242.5 773A 412 400 2250 0.01857 0.01842 5,026.0 0.0 603A 72.9 2,732.5 606,341.4 787.9 RWSr FEED AND BLEED REQUIRED (OALLONS) 13,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,747.9 607,356.9 1,078.9 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 179.5 3,927.4 619p07.2 1,107.7 370 350 2250 0.01804 0.01781 7,744.2 0.0 929E 1123 4p39.7 627,763E 1,125.1 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,039.7 634,538.0 1,113.1 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,039.7 628p623 1,122.9 ADD IN RIIRS VOLUME (ASSUME BORONCONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,579.3 712p74.4 1,122.9 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 307.9 4,8873 734,508.7 1,1633 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 265A 5,152.6 753p673 1,1%3 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 99.9 5,252.6 760p56.5 1,208.2 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109E 134.1 5,386.7 769A34.0 1,224.0 l TOTAL BAT VOLUME = 8,803.9 G ALLONS l l TOTAL RWST VOL 23,344.2 GALLONS l 25FB400 ABB Combustion Engineering Nuclear Services Page 64 of167

_ - - - - - .._________ _-_ .__ _ ____.___ _ _ ___.___ _ __ _ - - ,_ , . . _ , ,,_-c, ._.

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV. 2 TABLE 2-10 SEQUOYAH PLANT COOLDOWN FROM 547 F TO 200 F BAT AT1625 wt% BORIC ACID; RWST AT 2500 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUM E SHRINKAGE BAT VOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRESS. MASS @ 70*F @ 70*F ADDED B/A MASS CONC (cu.ft./lbm)

Ti ('F) Tf(*F) (psia) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibtn) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 a0 0.0 a0 0.0 525,254.9 RO 547 540 2250 0.02125 0.02106 4,73& 2 56&6 0.0 17&1 178.1 530,169.2 S&7 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 479.5 657.6 543,395.9 211.6 i

520 500 2250 0.02055 0.02009 11,91 & 8 1,431.0 0.0 44& 3 1,105.9 555,7610 347.9 500 485 2250 0.02009 0.01979 8,158.3 979.5 0.0 306.9 1,412.8 564,22& 2 437.8 485 450 2250 a01979 0.01916 18,111.4 2,174.5 0.0 681.2 2,094.0 583,020.8 627.9 450 422 2250 0.01916 0.01872 13,1162 1,574.8 no 4913 2,587.3 596,630.3 75 & 2 422 400 2250 a01872 0.01842 9,56& O 0.0 1,14&5 13&8 2,72&1 606,335.0 78&1 RWST FEED AND BLEED REQUIRED (OALLONS) 13,500 400 400 2250 0.01842 0.01842 0.0 0.0 a0 RO 3,742.6 607,351.6 1,077.4 400 370 2250 0.01842 0.01804 12,370.9 a0 1,485.3 179.5 3,9211 619,901.9 1,10&2 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 1113 4,034.4 627,75 &5 1,1216 350 350 350 a02698 0.01912 6,774.3 0.0 8113 a0 4,034.4 634,532.7 1,111.6 350 350 350 0.01781 0.01797 (5,575.7) OLO (669.4; 0.0 4,034.4 628,957.0 1,121.5 ADD IN RIIRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) 350 350 350 a01797 0.01797 0.0 a0 0.0 a0 4,5713 712,96& 4 1,121.5 350 300 350 a01797 0.01743 21,22& 4 a0 2,54&5 307.9 4,881.2 734,502.7 1.161.9 300 250 350 0.01743 0.01699 18,2912 0.0 2,196L3 265.4 5,14&6 753,061.3 1,194.9 250 230 350 0.01699 0.01683 6,889.2 a0 827.1 99.9 5,2466 760,050.5 1,2069 230 200 350 0.01683 0.01662 9,2414 a0 1,109.8 134.1 5,380.6 769,42& O 1,2216 i l TOTAL BAT VOLUME 8,258.9 GALLONS l l TOTAL RWST VOL 23,889.2 GALLONS l 25FB400 i ABB Combustion Engineering Nuclear Services Page 65 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV. 2 TABLE 2-11 SEQUOYAH PLANT COOLDOWN FROM 547 F TO 200 F BAT AT 3.75 wt% DORIC ACID: RWST AT 2500 ppm DORON; PZR @ 0% POWER LEVEL AVG.SYS. TEM P PZR SPECIFIC VOLUM E SIIRIN KAOE BAT VOL RWSTVOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70*F @ 70*F ADDED B/A MASS CONC.

(cu.ft/lbm)

Ti(*F) Tr(*F) (psia) Vi Vf (Ibm) (gallons) (gallons) (ibm) (Ibm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5684 0.0 184.5 1843 530,175.6 60.9 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 496.6 681.2 543,419.5 219.2 520 510 2250 0.02055 0.02031 6,089.2 731.1 0.0 237.2 918A 549,745.9 292.1 510 480 2250 0.02031 0.01% 9 16,762.6 2,012.6 0.0 653.1 1,571.5 567,161.6 484A 480 450 2250 0.01 % 9 0.01916 15,336.7 1,841.4 0.0 597.5 2,169.0 583p95.8 650A 450 431 2250 0.01916 0.01886 8,965.7 1,076.4 0.0 3493 2,518 3 592,410.8 7432 431 400 2250 0.01886 0.01842 13,716.5 0.0 1,646.8 199D 2,7173 606,3263 7833 RWST FEED AND BLEED REQUIRED (GALLONS) 13,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,7353 607,344.2 1,0753 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,485.3 179.5 3,914.8 619$94.6 1,104.1 370 350 2250 0.01804 0.01781 7,744.2 0.0 9293 1123 4,027.1 627,751.1 1,121.6 350 350 350 0.02698 0.01912 6,774.3 0.0 8133 0.0 4,027.1 634,525.4 1,109.6 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,027.1 628p49.7 1,119.4 ADD IN RIIRS VOLUME (ASSUME DORONCONC. = RCS BORON CONC.)

350 350 350 0.01777 0.01797 0.0 0.0 0.0 0.0 4,565.0 712p60.1 1,119.4 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 307.9 4,873.0 734,494.4 1,159.9 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%.3 265A 5,138.3 753p53.0 1,192.9 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 99.9 5,238 3 760p423, 1,205.0 230 200 350 0.01683 0.01662 9,243.4 0.0 1,107.8 134.1 5,372.4 769,419.7 1,220.8 l TOTAL BAT VOLUME 7,760.5 GALLONS l l TOTAL RWST VOL 24,387.6 G ALLONS l 25FB400 ABB Combustion Engineering Nuclear Services PaDe 66 of167

ABB Combustion Engineering Nuclear Services Page 64 of 167 BORIC ACID CONCENTRATION REDUCTION EFFORT TECHICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV. 2 TABLE 2-12 SEQUOYAH PLANT COOLDOWN FROM 547 F TO 200 F BAT AT3.875 wt% BORIC ACID: RWST AT 2500 ppm DORON: PZR @ 0% POWER LEVEL AVG.SYS. TEMP PZR SPECIFIC VOLUME SIIRIN KAGE BAT VOL RW5rVOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70*F @ 70*F ADDED B/A MASS CONC.

(cu.ft/lbm)

Ti(*F) Tf(*F) (psia) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 1909 1903 530,182.0 63.0 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 5133 7042 543/43.1 226.7 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 480.5 1,1853 555A423 372E 500 470 2250 0.02009 0.01951 16,141.2 1,938.0 0.0 650.7 1,836.0 572,634.2 560.5 470 450 2250 0.01951 0.01916 10,128.5 1,216.1 0.0 4083 2,244.3 583,171.1 672E 450 437 2250 0.01916 0.01895 6,151.3 738.5 0.0 248.0 2,492.2 589,570.4 739.1 437 400 2250 0.01895 0.01842 16,530.8 0.0 1,984.7 239E 2,732.0 606,341.0 787E RW5r FEED AND BLEED REQUIRED (OALLONS) 13,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,747.6 607,356.5 1,078.8 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 179.5 3,927.0 619,906.9 1,107.5 370 350 2250 0.01804 0.01781 7,744.2 0.0 929E 1123 4,039.4 627,763.4 1,125.0 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 4,039.4 634,537.7 1,113.0 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,039.4 628p62.0 1,122.8 ADD IN RIIRS VOLUM E(ASSUMB BORONCONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,578.9 712374.0 1,122.8 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 3073 4,886.8 734,5083 1,163.2 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%J 265.4 5,152.2 753p66.9 1,1%.2 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 99.9 5,252.2 760p56.1 1,208.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 134.1 5,386.2 769,433.6 1,223.9 l TOTAL BAT VOLUME 7,422.6 GALLONS l l TOTAL RWST VOL 24,725.5 G ALLO _NS l 25FB400 ABB Combustion Engineering Nuclear Services Page 67 of167 1

_ _ _ _ _ _ . _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ ____ _-___.___m_e ., - - - = c- e e _ . _

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV. 2 TABLE 2-13 SEQUOYAH PLANT COOLDOWN FROM 547 F TO 200 F BAT AT4.00 wt% DORIC ACID; RW5r AT 2500 ppm BORON; PZR @ 0% POWER LEVEL AVG.SYS. TEM P PZR SPECIFICVOLUME SIIRIN KAOE BAT VOL RW5rVOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70*F @ 70*F ADDED B/A MASS CONC.

(cu.ft./lbm)

Ti('F) Tf(*F) (psia) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 535 2250 0.02125 0.02092 8,049.9 966.5 0.0 335A 335A 5334403 1093 535 520 2250 0.02092 0.02055 9,433.4 1,132.6 0.0 393.1 728.5 543A66.8 234 3 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 496I 1,225.1 555A82.2 3853 500 480 2250 0.02009 0.01 % 9 10,933.0 1,312.6 0.0 455.5 1,680.6 567,270.7 518D 480 460 2250 0.01 % 9 0.01933 10,371.3 1,245.2 0.0 432.1 2,112.8 578p74.2 639D 460 450 2250 0.01933 0.01916 4,965.4 596.2 0.0 206S 2,319.6 583,246.4 6953 450 444 2250 0.01916 0.01906 2,843.1 341A 0.0 118.5 2,438.1 586,208.0 727.2 444 420 2250 0.01906 0.01869 11,200.1 0.0 1,344.7 162.5 2,600.6 597,570.6 7603 420 400 2250 0.01869 0.01842 8,638.9 0.0 1,037.2 1253 2,725.9 606334.8 786D RWST FEED AND BLEED REQUIRED (OALLONS) 13,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,742.5 607,351.4 1,077.3 400 385 2250 0.01842 0.01822 6,446.7 0.0 774D 93.5 3,836.0 613,891.6 1,092.5 385 370 2250 0.01822 0.01804 5,924.2 0.0 7113 85.9 3,921.9 619p01.8 1,106.1 370 360 2250 0.01804 0.01792 4,015.6 0.0 482.1 58.3 3,980.2 623,975.7 1,115.2 360 350 2250 0.01792 0.01781 3,728.5 0.0 447.7 54.1 4,034.3 627,7583 1,123.6 350 350 350 0.02698 0.01912 6,774.3 0.0 8133 0.0 4,034.3 634,532.6 1,111.6 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,0343 628356.9 1,121.4 ADD IN RIIRS VOLUME (ASSUME DORONCONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,573.1 712,968.2 1,121.4 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 3073 4,881.1 734,502.5 1,161.8 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%.3 265A 5,146.4 753p61.1 1,194.8 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 99.9 5,246.4 760p503 1,206.8 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 134.1 5,380.5 769A27.8 1,222.6 l TOTAL BAT VOLUME 7,025.5 GALLONS l l TOTAL RWSTVOL 25,122.6 GALLONS l l 25FB400 ABB Combustion Engineering Nuclear Servic0s Page 68 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2

, TABLE 2-14 .

SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200"F

, BAT AT 3.50wt% BORIC ACID; RWST AT 2550 ppn BORON; PZR @ 0% POWER LEVEL AVG.SYS.'IEMP PZR SPECIFICVOLUME SHRINKAGE BATVOL RWST VOL B/A TOTAL 'IDTAL SYS. FINAL PRESS. MASS @ 70'F @ 70'F ADDED B/A MASS CONC (cu.ft/lbm) n CF) TfCF) (psia) Vi Vf @m) (gallons) (ganons) @m) @m) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 04 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 1713 1713 530,162.9 564 540 520 2250 0.02106; 0.02055 12,747.2 1,530 3 0.0 4623 634.1 543,372.4 204D 520 500 2250 0.02055 0.02009 11,918E 1,431.0 . 0.0 4323 1,066.4 555,723.5 3353 500 480 2250 0.02009 0.01969 10,933.0 1,312.6 0.0 3%3 1,462.9 567p534 451.1 480 450 2250 021%9 0.01916 15,336.7 1,841.4 0.0 5563 2,019.2 582#46.0 6056 450 415 2250 0.01916 0.01862 16,296.0 1,956 3 0.0 591.1 2,6103 599)t332 7608 415 400 2250 0.01862 0.01842 6,386.1 0.0 766.7 943 2,7043 606,313.7 719 9 RWST FEED AND BIEED REQUIRED (OALLONS) 13,000 400 400 2250 0.01842 0.01842 0.0 OD 0.0 04 3,719.0 607,327.9 1,070 4 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 183.1 3,902.1 619)l82D 1,100 4

, 370 350 2250 0.01804 0.01781 7,744.2 0.0 9292 1146 4,016.7 627,740 2 1,118.7 350 350 350 0.02698 0.01912 6,7743 0.0 8133 OD 4,016.7 634,515A 1,106.8 350 .350 350 021781 0.01797 (5,575.7) 0.0 (669A) OA 4,016.7 628,939 3 1,116 4 ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 04 OD 4,553 3 712,9483 1,116 4 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548 3 314.2 4,867.4 734A88.9 1,1584 300 250 350 041743 0.01699 18,293.2 0.0 2,1%3 2703 5,138.2 753p52.9 1,192.9 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 102D 5,240.2 760 044.1 1,205.4

] 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1363 5,377.0 769A243 1,221.8 l TOTAL BATVOLUME = 8,640.6 GALLONS l l TOTAL RWST VOL 23,007.5 GALLONS l 255FB400 ABB Combustion Engineering Nuclear Services Page 69 of 167 h

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

. u _ . . _ _ _ . . _ _ . _ _ _.-.--.-._._m . _ _ . . _ . _ . - . . . _ . _ . _ _ - . _ . _ . _ . . _ - - _ . ~ _ _.

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-15 SEQUOYAH PLANT COOLDOWN FROM 547"F TO 200"F BAT AT 3.625 wt% BORIC ACID: RWST AT 2550 ppm BORON; PZR @ 0% POWER LEVEL AVO.SYS. TEMP PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A 'IDTAL TOTAL SYS. FINAL PRESS. MASS @ 7(TF @ 7(TF ADDED B/A MASS CONC (cult /lbm)

Ti(P) '1T(T) (psia) Vi Vf (Ibm) (gallons) (gallons) (1bm) (Ibm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254 S 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 178.1 178.1 530,169.2 58.7 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 4795 6576 543,395.9 2116 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 4483 1,105.9 555,763.0 3479 500 485 2250 0.02009 0.01979 8,158 3 9795 0.0 3069 1,412.8 564,228.2 4373 485 450 2250 0.01979 0.01916 18,111.4 2,174.5 0.0 6812 2 # 94.0 583p20E 627.9 450 425 2250 0.01916 0.01877 11,731.1 1,408.5 0.0 4412 2,535.2 595,193.2 744.7 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 162.1 2,6973 606,3063 777E RWST FEED AND BIEED REQUIRED (OALLONS) 13,000 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,712E 607,321.7 1,068.8 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 183.1 3,895.9 619,875.7 1,098.8 370 350 2250 0.01804 0.01781 7,744.2 0.0 9293 114 6 4p10.5 627,734 5 1,117.0 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 4 # 10.5 634,508.8 1,105.1 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669A) 0.0 4S10.5 628,933.1 1,114.9 ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) 350 350 350 0.01777 0.01797 0.0 0.0 0.0 0.0 4,546.2 712,941.2 1,114.9 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 314.2 4,860.4 734A81.8 1,156.9 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%3 2703 5,131.1 753945E 1,1913 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 102D 5,233.1 760 037.0 1,2(B.8 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1362 5,369.9 769A173 1,220.2 l TOTAL BATVOLUME = 8,092.6 GALLONS l l TOTAL RWST VOL 23,555.5 GALLONS l 255FB400 ABB Combustion Engineering Nuclear Services Page 70 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT 4

TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-16 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F BAT AT 3.75 wt% BORIC ACID; RWST AT 2550 prun BORON: P2R @ 0% POWER LEVEL

, AVG.SYS. TEMP PZR SPECIFICVOLUME SHRINKAGE BATVOL RWSTVOL B/A TOTAL 'IUTAL SYS. FINAL PRESS. MASS @ 70'F @ 70'F ADDED B/A MASS CONC (cult /lbm) _

i 71(P) 'IY(7) (psia) VI Vf (Ibm) (gallons) (gaDons) (1bm) (Ibm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.0000 ! 0.0 0.0 OA 0.0 0.0 525,2543 DD s $47 540 2250 0.02125 0.02106 4,736.2 5686 OD 1845 1843 530,175.6 60.9 540 520 2250 0D2106 0.02055 12,747.2 1,5303 0.0 4%6 681.2 543A19.5 219.2 520 510 2250 0.02055 0.02031 6,089.2 731.1 0.0 237.2 918A 549,745 S 292.1 510 480 2250 0.02031 0.01 % 9 16,762.6 2,0124 OD 653.1 1,571 3 567,161.6 484A i

480 450 2250 0.01 % 9 0.01916 15,336.7 1,841.4 04 597.5 2,1694 583#95A 650A i 450 433 2250 0.01916 0.01889 8,024.5 963A 0.0 3124 2,481.7 591/32.9 7336 433 400 2250 0.01889 0.01842 14,657.7 0.0 1,759A 217D 2,698.6 606,3074 778.2 I 13,000 RWST FEED AND BIE.ED REQUIRED (OALLONS) i 400 400 2250 0.01842 0.01842 0.0 0.0 OA 0.0 3,713 3 667,3222 1,069.1

400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 183.1 3,8974 619#76A 1,099.1 370 350 2250 0.01804 OD1781 7,744.2 0.0 929A 1146 4,0114 627,735 4 1,1173 350 350 350 0.02698 0.01912 6,7743 OD 8133 0.0 4,011.6 634,5093 1,105A

. 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669A) 0.0 4411.6 628 934.2 1,115.2

) ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) i 350 350 350 0.01797 0.01797 0.0 04 0A 0.0 4,547.4 7129425 1,115.2 350 300 350 0.01797 0.01743 21,226.4 OD 2,5483 314.2 4,861.6 734A83.1 1,157.2 4

300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%3 270A 5,132.4 753p47.1 1,191.6 l 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 102D 5,2343 760 #383 1,204.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109A 136A 5,371.1 769A183 1,220 3 l TOTAL BAT VOLUME = 7,647.5 GALLONS l l TOTAL RWST VOL 24,000.6 GALLONS l

, 255FB400 ABB Combustion Engineering Nuclear Services Page 71 of 167 n

+

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-17 SEQUOYAH PLANT COOLDOWN FROM 547*F TO 20CTF BAT AT 3.875 wt% BORIC ACID; RWST AT 2550 ppm BORON; PZR @ 0% POWER LEVEL AVG.SYS. TEMP PZR SPECIFICVOLUME SHRINKAGE BAT VOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRESS. MASS @ 7(TF @ 70'F ADDED B/A MASS CONC (cult /lbm)

T1(P) Tf('F) (psia) Vi Vf (Ibm) (gallons) (gations) (Ibm) (Ibm) (ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 OD 0.0 OD 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 1909 1909 530,182.0 63.0 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 5139 7043 543,443.1 226.7 520 500 2250 0.02055 0.02009 11,918E 1,431D 0.0 4805 1,185 3 555,8423 372E 500 470 2250 0.02009 0.01951 16,141.2 1,938.0 OD 650.7 1,836D 572434.2 5605 470 450 2250 0.01951 0.01916 10,128.5 1,216.1 OD 4083 2,2443 583,171.1 672E 450 440 2250 0.01916 0.01900 4,754.5 5703 OD 191.7 2,435.9 588,117.2 724.1 440 400 2250 0.01900 0.01842 17,927.6 0.0 2,152.4 2653 2,7013 606,310.2 7789 RWST FEED AND BLEED REQUIRED (GALLONS) 13,000 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,716.1 607,325.0 1,069.8 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 IfG.1 3,899.2 619,879.0 1,099.7 370 350 2250 0.01804 0.01781 7,744.2 0.0 9293 114 6 4,013E 627,737E L117.9 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 4,013.8 634,512.1 1,105D 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669A) 0.0 4,013.8 628 936.4 1,115.8 ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 OD OD 4,549.9 712,945 4 1,115.8 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 3142 4,864.1 734,485 4 1,157E 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%3 2703 5,134.9 753J)t9.6 1,192.2 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 1024 5,236.8 760940E 1,208.6 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109E 1363 5,3734 769A21D 1,221.0 l TOTAL BAT VOLUME =: 7,254.9 GALLONS l l TOTAL RWST VOL 24,393.2 GALLONS l 255FB400 ABB Combustion Engineering Nuclear Services Page 72 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-18 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200"F BAT AT 4.00wt% BORIC ACID: RWST AT 2550 ppm BORON: PZR @ 0% POWER LEVEL

, AVG.SYS. TEMP PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A TOTAL 'IUTAL SYS. FINAL ,

i PRESS. MASS @ 70'F @ 70 7 ADDED B/A MASS CONC j (cu.ft./lbm)

'Il (P) "IY(*F) (psia) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 535 2250 0.02125 0.02092 8,049.9 966.5 0.0 335A 335A 5334403 1099

) 535 520 2250 0.02092 0.02055 9,433.4 1,132.6 0.0 393.1 728.5 543A662 2343 j 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 4%6 1,225.1 555A82.2 3853 4 500 480 2250 0.02009 0.01 % 9 10,933.0 1,312.6 0.0 4555 1,680 4 567,270.7 518D j 480 460 2250 0.01969 0.01933 10,3713 1,245.2 0.0 432.1 2,112.8 578p74.2 639D 460 450 2250 0.01933 0.01916 4,965.4 5%2 0.0 2069 2,319 4 583,246.4 6953 2,398.5 7166

~

450 446 2250 0.01916 0.01909 1,892.2 227.2 0.0 78.8 585,217.5 j 446 420 2250 0.01909 0.01869 12,151.0 0.0 1,458.9 1793 2,578 3 597,548A 754A 420 400 2250 0.01869 0.01842 8,638.9 0.0 1,037.2 1273 2,706.2 606,315.1 7803 RWST FEED AND BLEED REQUIRED (GALLONS) 13,000 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,720.2 6(T1,329.1 1,070.9

400 385 2250 0.01842 0.01822 6,446.7 0.0 774D 95.4 3,815.6 613A71.2 1,086.7 385 370 2250 0.01822 0.01804 5,924.2 0.0 7113 87.7 3,9033 619A83.2 1,100.9 370 360 2250 0.01804 0.01792 4,015.6 0.0 482.1 59.4 3,962.7 623,958.2 1,110.4 l 360 350 2250 OD1792 0.01781 3,728.5 0.0 447.7 55.2 4 # 17.9 627,742D 1,119.0 i 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,017.9 634,516.2 1,107.1 350 350 350 350 350 0.01781 0D1797 (5,575.7) 0.0 (669A) 0.0 4,017.9 628,940.5 1,116.9 l

l ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) l 350 350 350 0.01777 0.01797 0.0 0.0 0.0 0.0 4,554 4 71259.7 1,116.9 l 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 3142 4,868.8 734A903 1,158.9 L 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%3 270A 5,139.6 753p543 1,193.2 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 102D 5,241.5 7600453 1,205.7 l

230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1363 5,378 3 769A25.7 1,222.1 i

l TOTAL BATVOLUME = 6,911.3 GALLONS l l TOTAL RWST VOL 24,736.8 GALLONS l

! 255FB400 ABB Combustion Engineering Nuclear Services Page 73 of 167 4

.___.___________._____._m_. m__,_-,.,.,_m_.__ ____,-.-.,,mm.._,w,.- ----.,,,_,m..,_-,._.._m_.-m,....

. %+_.,. .. ,_..,m__,-___ .,_.,,m._ ._ _ . . _ , . _.

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-19 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F DAT AT 3.50wt% BORIC ACID; RWST AT 2600 ppm BORON: PZR @ 0% POWER LEVEL AVG.SYS. TEMP PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A TOTAL ! TOTAL SYS. FINAL PRESS. MASS @ 70'F @ 70'F ADDED B/A MASS CONC.

(cu.ft/lbm)

Ti (*F) Tf(*F) (psia) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 1713 1713 530,162.9 56.6 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 4623 634.1 543,372.4 204D 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 4323 1,066.4 555,723.5 3355 500 480 2250 0.02009 0.01 % 9 10,933.0 1,312.6 0.0 3%5 1,462.9 567/153.0 451.1 480 450 2250 0.01 % 9 0.01916 15,336.7 1,841.4 OD 5563 2,019.2 582S46D 6056 450 418 2250 0.01916 0.01866 14,942.2 1,794D 0.0 542D 2,561.1 598A30.2 7483 418 400 2250 0.01866 0.01842 7,739.9 0.0 9293 1163 2,678.0 606,286.9 772.2 RWST FEED AND BLEED REQUIRED (GALLONS) 12,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,6883 607,297.2 1,061.8 400 370 2250 0.01842 0.01804 12,370.9 OD 1,4853 186.7 3,875.0 619,854.9 1,093.0 370 350 2250 0.01804 0.01781 7,744.2 0.0 9292 116S 3,991 S 627,716.0 1,111E 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,9 91 S 634A90.2 1,100.0 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669A) 0.0 3,991 S 628 S14.5 1,109.7 ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 OD 0.0 4,525.1 712,920.2 1,109.7

- 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 320A 4,845.6 734A67.0 1,153.4 300 250 350 0.01743 0.01699 18,293.2 OD 2,1%3 276.1 5,121.7 753/136.4 1,189.1 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104D 5,225.7 760/129.7 1,202.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109E 139.5 5,3653 769/12.6 1,219.2 l TOTAL BAT VOLUME = 8,478.1 GALLONS l l TOTAL RWST VOL 22,670.0 GALLONS l 26FB400 ABB Combustion Engineering Nuclear Services Page 74 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-20 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F BAT AT 3.625 wt% BORIC ACID; RWST AT 260G ppm BORON; PZR @ 0% POWER LEVEL AVG.SYS. TEMP PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWSTVOL B/A TOTAL TOTAL SYS FINAL PRESS. MASS @ 7(TF @ 7(TF ADDED B/A MASS CONC.

(cu.ftJIbm)

Ti(P) 1T(T) (psia) Vi Vf (Ibm) (gations) (gallons) (Ibm) (1bm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 178.1 178.1 530,169.2 58.7 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 4793 6576 543,395.9 211 6 520 500 2250 0.02055 0.02009 11,918R 1,431.0 0.0 4483 1,105.9 555,763.0 3479 500 485 2250 0.02009 0.01979 8,158 3 979.5 0.0 3069 1,412E 564,228.2 4373 485 450 2250 0.01979 0.01916 18,111.4 2,174.5 0.0 6812 2,0 94.0 583p20.8 6279 450 428 2250 0.01916 0.01881 10,352.7 1,243.0 0.0 389A 2,483.4 593,762.9 7312 428 400 2250 0.01881 0.01842 12,329.4 0.0 1,480 3 186.1 2,669.5 606278.4 7693 RWST FEED AND BLEED REQUIRED (GALLONS) 12,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,681.1 607,290.1 1,059.8 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 186.7 3,867.9 619,847.7 1,091.0 370 350 2250 0.01804 0.01781 7,744.2 0.0 929E 1169 3,984.8 627,708.8 1,109.9 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,984.8 634A83.1 1,098.0 350 350 350 0.01781 0.01797 (5,5 75.7) 0.0 (669A) 0.0 3,984.8 628,907.4 1,1W.8 ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,517.0 712,912.1 1,1W.8 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 3204 4,837.5 734A58.9 1,1515 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%3 276.1 5,113.6 753p283 1,1873 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104D 5,217.6 760p21.6 1,200.2 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109E 1393 5,357.1 769,404.5 1,217 3 lTOTALBATVOLUME = 7,927.1 GALLONS l l TOTAL RWST VOL 23,221.0 GALLONS l 26FB400 ABB Combustion Engineering Nuclear Services Page 75 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-21 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200 F BAT AT 3.75 wt% BORIC ACID; RWST AT 2600 ppm DORON: PZR @ 0% POWER LEVEL AVG.SYS. TEMP rza SPECIFIC VOLUME SHRINKAGE BAT VOL RWST VOL B/A 70TAL 7DTAL SYS. FINAL PRESS. MASS @ 7(TF @ 7(TF ADDED B/A MASS CONC (cult /lbm)

'll (T) Tf('F) (psia) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (1bm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 1845 1845 530,175.6 60.9 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 4966 6812 543A19.5 219.2 520 510 2250 0.02055 0.02031 6,089.2 731.1 0.0 2372 918A 549,745.9 292.1 510 480 2250 0.02031 0.01 % 9 16,762.6 2,012.6 0.0 653.1 1,571.5 567,161.6 484A 480 450 2250 0.01 % 9 0.01916 15,336.7 1,841.4 0.0 577.5 2,169.0 583p95.8 650A 450 435 2250 0.01916 0.01892 7,086.4 8503 0.0 276.1 2,445.1 590A583 724D 435 400 2250 0.01892 0.01842 15,595.8 0.0 1,872.5 235A 2,680 I) 606,289.5 773D RWST FEED AND BIEED REQUIRED (OALLONS) 12,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 ' O.0 3,690.4 607,299.4 1,062.4 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 186.7 3,877.2 619,857.0 1,0 93.6 370 350 2250 0.01804 0.01781 7,744.2 0.0 929E 1169 3,994.1 627,718.1 1,112.4 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,994.1 1,100.6 634A92.4 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669A) 0.0 3,994.1 628,916.7 1,1103 ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,527.6 712 722.6 1,110 3 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548 3 320A 4,848.0 734A69.5 1,154.0 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%3 276.1 5,124.2 753 #38.9 1,189.7 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 IND 5,228.2 1,202.7 760 #32.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1395 5,367.7 1,219.7 769A15.1 l TOTAL BAT VOLUME = 7,534.9 GALLONS l l TOTAL RWST VOL 23,6132 GALLONS l 26FB400 ABB Combustion Engineering Nuclear Services Page 76 of 167

_ _ ______ _ _ _ _ _ - - - _ _ _ _ _ = - _ _ _ _ _ - _ _ _ _ _ _ _ _ _

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-22 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F BAT AT 3E75 wt% BORIC ACID; RWST AT 2600 ppm BORON; PZR @ 0% POWER LEVEL AVG.SYS. TEMP PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A TVTAL 7DTAL SYS. FINAL PRESS. MASS @ 7FF @ 70'F ADDED B/A MASS CONC (cu.ft/lbm) 11(P) 1T('F) (psia) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 5686 0.0 1909 1909 530,182.0 63.0 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 5139 7043 543A43.1 226.7 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 480.5 1,1853 555$423 372E 500 470 2250 0.02009 0.01951 16,141.2 1,938.0 0.0 650.7 1,836.0 572/i34.2 5605 470 450 2250 0.01951 0.01916 10,128 3 1,216.1 0.0 4083 2,244 3 583,171.1 6723 450 443 2250 0.01916 0.01904 3,319.8 3986 0.0 1333 2,378.1 586/i24.6 708.7 443 400 2250 0.01904 0.01842 19,362.4 0.0 2,324.7 2923 2,670.4 606,2793 770.1 RWST FEED AND BLEED REQUIRED (GALLONS) 12,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,681.8 607,2903 1,060.0 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 186.7 3,868.6 619A48.4 1,091.2 370 350 2250 0.01804 0.01781 7,744.2 0.0 9293 116S 3,985 3 627,709.5 1,110.1 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 3,9853 634A83.8 1,098.2 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669A) 0.0 3,9853 628,908.1 1,108.0 ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,517.9 712,912.9 1,108.0 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548 3 320A 4,838 3 734A59.7 1,151.7 300 250 350 0.01743 0.01699 18,293.2 0.0 2,196 3 276.1 5,114.4 753 #29.1 1,187.4 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104D 5,218.4 760 #22.4 1,200.4 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1393 5,358.0 769A053 1,217.5 l TOTAL BAT VOLUME = 7,082.7 GALLONS l l TOTAL RWST VOL 24,065.4 GALLONS l 26FB400 ABB Combustion Engineering Nuclear Services Page 77 of 167

___u _ _ _ _ - -_. - _ - _ _ . _ _ - _ -._-_,,__.__.__u- - _ _ - - _ _ _ - - = - - - - - - --- - - - + - - w--~- - - - * --+ -- -- _ - _ . _ - _ _ _ _ _ _ _ _. _ _ - _ _ - -

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-23 SEQUOYAH PLANT COOLDOWN FROM 547 F TO 200 F BAT AT 4 00 wt% BORIC ACID; RWST AT 2600 prun BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEMP PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A TOTAL 'IUTAL SYS. FINAL PRESS. MASS @ 7(TF @ 70'F ADDED B/A MASS CONC.

(cu.ft/lbm)

Ti (P) Tf(P) (psia) Vi Vf (Ibm) (gallons) (gations) (Ibm) (Ibm) (1bm) (ppm boron]

547 547 2250 1.00000 1.00000 0.0 0.0 0.0 OD OD 525,254.9 OD 547 535 2250 0.02125 0.02092 8,G49.9 9665 0.0 335A 335A 5334403 1099 535 520 2250 0.02092 0.02055 9,433.4 1,132.6 0.0 393.1 7285 543A66.8 2343 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 49M 1,225.1 555E82.2 3853 500 480 2250 0.02009 0.01 % 9 10,733.0 1,312.6 0.0 4555 1,680.6 567,270.7 518D 480 460 2250 0.01969 0.01933 10,3713 1,245.2 0.0 432.1 2,112.8 578/T14.2 639D 460 450 2250 0.01933 0.01916 4,965.4 5%2 0.0 2069 2,319.6 583,246.4 6953 450 448 2250 0.01916 0.01912 9445 113A 0.0 39A 2,359D 584,230 3 705S 448 420 2250 0.01912 0.01869 13,098.7 0.0 1,572.7 197.7 2,556.7 597,526.8 748.1 420 400 2250 0.01869 0.01842 8,638.9 0.0 1,037.2 130A 2,687.2 606,296.1 7749 RWST FEED AND BLEED REQUIRED (OALLONS) 12,500 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,696D 6(T7,304.9 1,064D 400 385 2250 0.01842 0.01822 6,446.7 0.0 774D 973 3,7933 613E48.9 1,080.4 385 370 2250 0.01822 0.01804 5,924.2 0.0 7113 89.4 3,882.8 619E62.6 1,095.1 370 360 2250 0.01804 0.01792 4,0 15.6 0.0 482.1 60.6 3,943.4 623F38.9 1,105D 360 350 2250 0.01792 0.01781 3,7283 0.0 447.7 563 3,999.7 627,723.7 1,114D 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,999.7 634A98.0 1,102.1 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669A) 0.0 3,999.7 628 S223 1,111 S ADD IN RHRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,533.9 712S29.0 1,111.9 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 320A 4,854 3 734A75.8 1,155.5 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%3 276.1 5,1303 753/)45.2 1,191.1 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104D 5,234 3 760/138.4 1,204.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1395 5,374D 769A21.4 1,221.1 l TOTAL BAT VOLUME = 6,797.5 GALLONS l l TOTAL RWST VOL 24,350.6 GALLONS l 26FB400 ABB Combustion Engineering Nuclear Services Page 78 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-24 SEQUOYAH PLANT COOLDOWN FROM 547*F TO 200-F D AT AT 3.50 wt% BORIC ACID: RWST AT 2650 rpm BORON:PZR @ 0% POWER LEVEL AVO.SYS. TEMP PZR SPECIFIC VOLUMB SilRINKAOB B AT VOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ ?O'F @ 70*F ADDED B/A MASS CONC (cu.ftJ1bm)

Ti (*F) Tr(*F) (reis) VI Vf (Ibm) (anilons) (gallone) (Ibm) (Ibm) (1bm) (ppa boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,2543 0.0 547 540 2250 0.02125 0.02106 4,7 % 2 568.6 0.0 171.8 1712 530,1623 %6 540 520 2250 0.02106 0.02055 12,7472 1,53a5 0.0 462 3 634.1 543,372.4 204.0 520 500 2250 0.02055 0.02009 11,9183 1,43LO 0.0 4323 1,06&4 555,7233 335.5 500 480 2250 0.02009 0.01% 9 10,933A 1,3116 0.0 3%.5 1,4619 567,053D 451.1 480 450 2250 0.01 % 9 0.01916 15,336.7 1,84 L4 0.0 556.3 2,019.2 582,946A 605.6 450 422 2250 0.01916 0.01872 13,1162 1,574.8 0.0 475.7 2.4949 596,5373 731.2 422 400 2250 0.01872 0.01M2 9,5M0 0.0 1,14&5 147.2 2,6411 606,251.1 762.0 12,250 RWST FEED AND BLEED REQUIRED (OALIENS) 400 400 2250 0.01M2 0.01M2 0.0 0.0 0.0 0.0 3,6%5 6&T,275A 1,0516 400 370 2250 0.01M2 0.01804 12370.9 0.0 1,4813 190.4 3,8%9 619,R36.7 1,087.9 370 350 2250 0.01804 0.01781 7,744.2 0.0 93.8 119.2 3,9761 627,700.1 1,107.5 350 350 350 0.02e8 0.01912 6,77(3 0.0 8133 0.0 3,97&1 634,474A 1,0916 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 3,97&1 628,898.7 1.1014 ADD IN RilRS VOLUMB(ASSUMB BORON CONC = RCS BORONCONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,507.2 712,902.2 1,1014 350 300 350 0.01797 0.01743 21,226.4 0.0 2,54& 5 326.7 4,8319 734,4553 1,1547 300 250 350 0.01743 0.01699 18,2932 0.0 2,1963 281.5 5.1114 753,030.1 1,187.7 250 230 350 0.0199 0.01683 6,889.2 0.0 827.1 106.0 5,22L4 760,025A 1,20L1 230 200 350 0.01683 0.01662 9,2414 0.0 1,109.8 1423 5,3617 7e9,411.1 1,2118 l TOTAL BAT VOLUME = 8,258.9 GAulONS l l TOTAL RWSTVOL 22,639.2 GALLONS l 265FB400 ABB Combustion Engineering Nuclear Services Page 79 of 167 1

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

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-25 SEQUOYAH PLANT COOLDOWN FROM 547T TO 20(PF B AT AT 3.625 wt% BORIC ACID: RWST AT 2650 ppm BOROK PZR @ 0% POWER LEVEL AVO.SYS. TEM P FZR SPECIFIC VOLUMB SilRINKAOB B AT VOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRESS. MASS @ 70*F @ 70*F - ADDED B/A MASS CONC (ca.Allbm)

Ti (*F) "I1(*F) (pela) VI Vf (Ibm) (sallone) (sallons) (1bm) (Ibs) (Ibe) (ppm boros) ;

547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,7362 568.6 0.0 178.1 178.1 530,1692 S&7 540 520 2250 0.02106 0.02055 12,747.2 1,53a5 0.0 479.5 657.6 543,395.9 211.6 520 500 2250 0.02055 0.02009 11,918A 1,43to 0.0 4463 1,1019 555,763.0 347.9 500 485 2250 0.02009 0.01719 8,15&3 979.5 0.0 306.9 1.4128 564,228.2 437.8 485 450 2250 0.01979 0.01916 18,111.4 2,17 (5 0.0 681.2 2,0940 583,020A 627.9 450 431 2250 0.01916 0.01886 8,9617 1,07&4 0.0 3 71.2 2,43 L2 592,323.7 717.6 431 400 2250 0.01886 0.01842 13,716.5 0.0 1,6468 211.1 2,6413 606,251.3 762.0

, RWSTFEED AND BLBED REQUIRED (OALIENS) 12,250 400 400 2250 0.01842 0.0lM2 0.0 0.0 0.0 0.0 3,6667 607,275A 1.0516 i

400 370 2250 0.01M2 0.01894 12370.9 0.0 1,4813 190.4 3,857.1 619,836.9 1,087.9 370 350 2250 0.01804 0.01781 7,744.2 0.0 9 29.8 119.2 3,9742 627,7003 1,107.5 350 350 350 0.02898 0.01912 6,7743 0.0 8133 0.0 3,97&2 634,474.5 1,0917 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 3,9742 628,898 3 1,1014 ADD IN RHRS VOLUMB(ASSUMB BORON CONC = RCS BORONCONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,507.4 712,902.4 1,1014 l 350 300 350 0.01797 0.01743 21,226.4 0.0 2,54& 5 326.7 4,8340 734,455.5 1,1547 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 281.5 5,1116 753,0303 1,187.7 !

250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 106.0 5,22L6 760,025.6 1,201.2 230 200 350 0.01683 0.01662 9,2414 0.0 1,109.8 1423 5,3619 769,411.2 1,21&8 l TOTAL BAT VOLUME = 7,760.5 GALLONS l l TOTAL RWSTVOL 23,137.6 GALLONS l 265FB400 ABB Combustion Engineering Nuclear Services Page 80 of 167 i

i [

i I

L Y

1

. .- m.-......,.m.m . .+--.s., ..v.-,. -..n.,- e-r, ..-_--.-#...%-w -re- .. .~,..m.-c-,-----,ww--~,.m -...-.v., n+-.,.m..m,- - r v. .-+.,.---,-.,,#.--. -.______.m_

m .-

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-26 SEQUOYAH PLANT COOLDOWN FROM S47T TO 2007 B AT AT 3.75 =t% BORIC ACID: RWST AT 2650 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEMP PZR SPECIFIC VOLUMB SilRINK AOB B AT VOL RWST YOL B/A TOTAL TOTAL SYS. FINAL PRESS. MASS @ 70*P @ 70*F ADDED B/A MASS CONC (cu.ft/tbm)

Ti (*F) 1T(*F) (psis) Vi vf (Ibm) (gellons) (sations) (Ibm) (Ibm) (1bm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,7362 568.6 0.0 184.5 184.5 530,175 4 6a9 540 320 2250 0.02106 0.02055 12,747.2 1,53a5 0.0 496.6 681.2 543,419.5 2 19.2 520 310 2250 0.02055 0.02G11 6,089.2 731.1 0.0 237.2 918.4 549,745.9 292.1 510 480 2250 0.02G11 0.01 % 9 16,762.6 2,0116 0.0 6 13.1 1,57 L5 567,1614 484.4 480 450 2250 0.01969 0.01916 15,336.7 1,84 L4 0.0 597.5 2,169.0 543,0952 6 30.4 450 439 2250 0.01916 0.01898 5,219.3 626.6 0.0 283.4 2,3714 588,518.5 704A 439 400 2250 0.01898 0.01842 17,462A 0.0 2,0966 268.8 2,641.1 606,250.1 761.7 RWST FEED AND BLEED REQUIRED (O ALLONS) 12,250 400 400 2250 0 01842 0.01842 0.0 0.0 0.0 0.0 3,6617 607,274 4 1,0513 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4813 150.4 3,8561 619,835.9 1,087.7 370 350 2250 0.01804 0.01781 7,7442 0.0 929.8 119.2 3,9712 627,6993 1,107.2 350 350 350 0.0288 0.01912 6,77(3 0.0 8133 0.0 3,9712 634,473.5 1,0914 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 6.0 3,9712 628,8972 1,1011 ADDIN RilRS VOLUMB(ASSUMB BORON CONC = RCS BORONCONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,5062 712,9013 1,1011 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548,5 326.7 4,8319 734,454 4 1,1545 300 230 350 0.01743 0.0le9 18,293.2 0.0 2,1963 281.5 5,1145 733,029.2 1,187.4 250 230 350 0.01699 0.01 s 3 6,889.2 0.0 827.1 106.0 5,22a5 760,024.4 1,20& 9 230 200 350 0.01683 0.01662 9,2414 0.0 1,109.8 1423 5,3617 769,410.1 1,2116 lTOTALBATVOLUME = 7,310.7 GALLONS l l TOTAL RWST VOL 23,587.3 GALLONS l 265FB400 ABB Combustion Engineering Nuclear Services Page 81 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLB 2-27 :

t SEQUOYAH PLANT COOLDOWN FROM 5471 TO 2001 B AT AT 3.875 wt% BORIC ACID: RWST AT2650 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEMP PZR SPECIFIC VOLUMB SilRINKAOB BAT VOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRESS. MASS @ 70*F @ 70*F ADDED B/A MASS CONC (cu.ft/lbe)

Ti (*F) TT('F) (peia) VI Vf (1bm) (asilone) (gallone) (Ibm) (Ibm) (Ibm) (ppm baron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254 3 0.0 547 540 2250 0.02125 0.02106 4,73&2 568.6 0.0 190.9 190.9 530,182A 610 540 520 2250 0.02106 0.02055 12,747.2 1,53a5 0.0 513.9 704.8 543,443.1 236.7 520 500 2250 0.02055 0.02009 11,9183 1,43 LO 0.0 480.5 1,1813 555,8423 372A 500 470 2250 0.02007 0.01951 16,1412 1,93&O 0.0 630.7 1,8360 57V ?*: 560.5 470 450 2250 0.01951 0.01916 10,128.5 1,21&1 0.0 408.3 2,2443 583. 71 1 672.8 450 445 2250 0.01916 0.01908 2,367.3 284.2 0.0 914 2.339.7 585,643 698.5 445 400 2250 0.01908 0.01842 20,3143 0.0 2,439.1 312.7 2,4513 606,2613 764.9 RWSTFEED AND BLEED REQUIRED (OALIENS) 12,250 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,6711I 6&T,284.1 1,05&1 400 370 2250 0.01842 0.01804 12,3703 0.0 1,4813 190.4 3,8615 619,845A 1,09t3 370 350 2250 0.01804 0.01781 7,7442 0.0 929.8 119.2 3,9847 627.708A 1,109.9 350 350 350 0.02e8 0.01912 6,7743 0.0 813.3 0.0 3,9847 634,483A 1,09E0 ,

3 50 350 330 0.01781 0.01797 (5,575.7; 0.0, (669.4 0.0 3,9847 628,9073 1,107.7 ADD IN RHR5 VOLUMB(ASSUMB BORON CONC = RCS BORONCONC)

! 330 330 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,517.0 712,912A 1,107.7 350 300 350 0.01797 0.01743 21.226.4 0.0 2,54&5 326.7 4,8417 734,465.1 1,1510 300 230 330 0.01743 0.01W9 18,293.2 0.0 2,1963 281.5 5,1212 753,0393 1,189.9 250 230 330 0.0199 0.01683 6,889.2 0.0 827.1 106.0 5,23L2 760,0352 1,2014 230 200 330 0.01683 0.01662 9,2414 0.0 1,109.8 142 3 5,3715 7#,4203 1,22LO l TOTAL B AT VOLUME = 6,968.3 GALLONS l l TOTAL RWSTVOL 23,929.8 GALLONS l 265FB400 ABB Combustion EngineerinD Nuclear Services PaDe 82 of 167 4

1 e

f e.* -- . . , . , - . . ~ . - - . . - , - .-----r.- - --e .-- - -e------ -- = = - - - .-w- w 2--,.--+--..- -,+- --_ _ _-- - --

i L

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-28 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200-F BAT AT4.00 W% BORIC ACID; RWST AT2650 ppm BOROM PZR @0% POWER LEVEL AVO.SYS.7EMP PZR SPFEIFIC VOLUME SIIRINKAGE BATVOL RWSTVOL IVA 7UTAL 7UTAL SYS. HNAL PRESS. MASS @ 70'F @ 70'F ADDED B/A MASS CONC.

(cu.ftJibm)

- T1 ('F) 71('F) (psia) Vi Vf 0bm) (adlons) (gallons) 0bm) 0bm) 0bm) (ppm txron]

i 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.') 0.0 525,254.9 0.0 i 547 535 2250 ~0.02125 0.02092 8,049.9 9663 0.0 335.4 335.4 5334403 109.9 4 535 520 2250 0.02092 0.02055 9,433.4 1,132.6 0.0 393.1 728 3 543,466A 2343 520 500 2250 0.02055 0.02009 11,9182 1,431.0 0.0 496.6 1.225.1 555A82.2 3853 i 500 480 2250 0.02009 0.01969 ' 10,933.0 1,312.6 0.0 455.5 1480.6 567,270.7 5 18.0 480 460 2250 0.01969 0.01933 10,371.3 1,245.2 0.0 432.1 . 2,112A 578,tr74.2 639.0 460 451 2250 0.01933 0.01917 4,464.9 536.1 0.0 186.0 2,298E 582,725.1 689.7

451 440 2250 0.01917 0.01900 5,255.0 0.0 630.9 8tL9 2,379.7 588 61.0 7U7.5

~

440 420 2250 0.01900 0.01869 9,2fB.8 0.0 1,115.2 143.0 2,5224 597,492.7 738.2 !

420 400 2250 0.01869 0.01842 8,638.9 0.0 1p37.2 133.0 24554 6052643 765.8 RWSTFEED AND RtP.Fn REQUIRED (OALLONS) 12,250 400 400 2250 0.01842 0.0184: 0.0 0.0 0.0 0.0 3477.9 607,286.8 1,05lL8 400 385 2250 0.01842 0.01822 6,446.7 0.0 774.0 99.2 3,777.1 613,832.7 1#75A 385 310 .2250 0.01822 0.01804 5,924.2 ,0.0 7113 9L2 3,868.3 619A48.1 1 # 91.1 310 360 .2250 0.01804 0.01792 4#154 0.0 482.1 61.8 3330.1 623,9254 1,1013 360 350 2250 0.01792 0.01781 3,728 3 0.0 447.7 57.4 3,9873 627,7113 1,110 4 350 350 350 0.02696 0.01912 6,7743 0.0 8133 0.0 3p87.5 634ASSE 1,098 2 350 350 350 0.01781 0.01797 (5,575.7] 0.0 (669Aj 0.0 3,987.5 628,910.1 1,108.5 i ADDIN RHRSVOLUME(ASSUME BORONCONC.= RCS BORONCONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,520.1 712315.1 1,1083 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 326.7 4A46.8 734A683 1,153.7 ;

) 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 2813 5,1283 753p43.0 1,1904 i

250 230 350 0.01699 0.01683 6,889.2 0.0 8ZT.1 106.0 _ 5,234.4 7e0A383 1,204.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 142.3 5,316 3 789,424JD 1,221.7 i

j l TOTAL BAT VOLUME = 6,624.0 GALLONS l l TOTAL RWSTVOL 24.274.1 GALLONS -l 265FB400 l ABB Combustion Engineering Nudear Services Page 83 of 167 I

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSES CEN-602, REV.2 TABLE 2-29 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200'F B AT AT 3.50 st% BORIC ACID; RWST AT 2700 rpm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SIIRINKAGE BAT VOL RWST VOL B/A TOTAL TOTAL 5YS. FINAL PR ESS. MASS @ 70 7 @ 707 ADDED B/A MASS CONC (cu.ft/tbm)

Ti(T) Tf(T) (pais) VI Vf Obm) (asilone) (an11one) Obm) Obm) Obm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 171.8 171.8 530,162.9 56.6 540 320 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 462.3 634.1 543,372.4 204.0

$20 500 2250 0.02055 0.02009 11,918 A 1,431.0 0.0 4323 1,066.4 555,723.5 335.5 500 480 2250 0.02009 0.01969 10,933.0 1,312.6 0.0 396.5 1,462.9 567,053.0 451.1 480 450 2250 0.01 % 9 0.01916 15,336.7 1,841.4 0.0 5563 2,019.2 582,946.0 605.6 450 424 2250 0.01916 0.01875 12,192.1 1,463.8 0.0 442.2 2,461.4 595,5803 7216 424 400 2250 0.01875 0.01842 10,490.1 0.0 1,259.5 164.5 2,625.9 606,234.9 7573 RWSTFEED AND BLEED REQUIRED (OALLONS) 12,000 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,660.1 607,269.1 1,053.8 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 194.0 3,854.2 619,834.0 1,087.1 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 121.5 3,975.7 627,699.7 1.107.3 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,975.7 634,473.9 1,095.5 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 3,975.7 628,898.2 1,105.2 ADD IN R11RS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,506.7 712,901.7 1,105.2 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,839.6 734,461.1 1,152.0 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 286.9 5,126.6 753,041 3 1,190.2 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5.234.6 760,038.6 1,204.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 145.0 5,379.6 769,427.0 1,222.4 l TOTAL BAT VOLUME = 0,147.9 GALLONS l l TOTAL RWST VOL 22,500.2 GALLONS l 27FB400 ABB Combustion Engineering Nuclear Services Page 84 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSES CEN-602, REV.2 TABLE 2-30 SEQUOYAH PLANT COOLDOWN FROM 547 F TO 200 F BAT AT 3.625 wt% BORIC ACID; RWST AT 2700 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME S11RINKAOB BAT VOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PR ESS. M ASS @ 70 7 @ 707 ADDED B/A MASS CONC (cu.ftJ1bm)

Ti(T) Tf(T) (pds) VI Vf (Ibm) (gallons) (gallons) (1bm) (1bm) (Ibm) (ppm borea) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 178.1 178.1 530,169.2 58.7 340 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 479.5 657.6 543,395.9 211.6 520 500 2250 0.02055 0.02009 11,918.8 1,431.0 0.0 448 3 1,105.9 555,763.0 347.9 500 485 2250 0.02009 0.01979 8,1583 979.5 0.0 306.9 1,412.8 564,228.2 437.8 485 450 2250 0.01979 0.01916 18.111.4 2,174.5 0.0 681.2 2,094.0 583,020.8 627.9 450 433 2250 0.01916 0.01889 8,024.5 953.4 0.0 301.8 2,395.8 591.347.1 708 3 433 400 2250 0.01889 0.01842 14,657.7 0.0 1,759.8 229.9 2,625.7 606,234.7 757.2 RWSTFEED AND BLEED REQUIRED (OALLONS) 12.000 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,660.0 607,268.9 1.C53.7 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 194.0 3,854.0 619,833.8 1,087.1 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 121.5 3,975.5 627,699.5 1,1073 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 3,775.5 634,473.8 1,095.5 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 3,975.5 628,898.1 1,105.2 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,506.5 712,901.5 1,105.2 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,839.4 734,460.9 1,152 0 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 286.9 5,126.4 753.041.1 1,190.2 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5,234.4 760,038.4 1,204.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 145.0 5,379.4 769,426.8 1,2223 l TOTAL BAT VOLUME = 7,647.5 GR10NS l l TOTAL RWSTVOL 23,000.6 GALLONS l 27FB400 ABB Combustion Engineering Nuclear Services Page 85 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSES CEN-602, REV.2 TABLB 2-31 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200'F BAT AT 3.75 wt% BORIC ACID: RWST AT 2700 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPBC1FIC VOLUMB SilRINKAOB BATYOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRBSS. MASS @ 70 7 6 707 ADDED B/A MASS CONC (ca.ft/lbm)

Ti(T) Tf(T) (pais) VI Vf Obm) (sallone) (gallone) (Ibe) (Ibe) (Ibm) (ppe boros) 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 184.5 184.5 530,175.6 60.9 540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 496.6 681.2 543,419.5 219.2 520 $10 2250 0.02055 0.02031 6,089.2 731.1 0.0 237.2 91 8.4 549,745.9 292.1 510 480 2250 0.02031 0.01969 16,762.6 2,01 2.6 0.0 653.1 1,571.5 567,161.6 484.4 480 450 2250 0.01969 0.01916 15,336.7 1,841.4 0.0 597.5 2,169.0 583,095.8 650.4 450 441 2250 0.01916 0.01901 4,275.4 513.3 0.0 166.6 2,335.6 587,537.9 695.0 441 400 2250 0.01901 0.01842 18,406.7 0.0 2,21 0.0 288.7 2,6243 606,233.3 756A 12,000 RWSTFBBD AND BLBED REQUIRBD(OALLONS) 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,65am 6e7,267.7 1,053.4 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,485.3 194.0 3,852.8 619,832.7 1.086.7 370 350 2250 0.01804 0.01781 7,744.2 0.0 9293 121.5 3,974.3 627,6983 1,107.0 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,9743 634,472.6 1,095.1 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 3,9743 628,896.9 1,104.9 ADD IN RIIRS VOLUMB (ASSUMB BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,505.1 712,900.2 1,104.9 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,838.1 734,459.6 1,151.7 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 286.9 5,125.0 753,039.7 1,189.9 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5.233.1 760,037.0 1,203.8 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 145.0 5,378.1 769,425.4 1,222.0 l TOTAL BATVOLUME = 7,197.4 GALLONS l l TOTAL RWST VOL 23,450.7 GALLONS [

27FB400 ABB Combustion Engineering Nuclear Services Page 86 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSES CEN-602, REV.2 TABLE 2-32 i SEQUOYAH PLANT COOLDOWN FROM 547*F TO 20(PF B AT AT 3.875 wt% BORIC ACID: RW5T AT 2700 ppm BOMON PZR e 0% POWER LEVEL AVO.5YS. TEM P PZR SPECIFICVOLUMB SHRINKAOB BAT VOL RW5T VOL B/A TOTAL TOTAL 5YS. FINAL PR ESS. MASS @ 70 7 9 707 ADDED B/A MASS CONC ,

(es.ftJtbs)

Ti(T) Tf(7) (pala) VI Vf Obs) (sellona) (sallona) Oba) Obs) Obs) (ppmboros)

- 547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 190.9 190.9 530,182.0 63.0 ,

540 520 2250 0.02106 0.02055 12,747.2 1,530.5 0.0 513.9 704A 543,443.1 726.7 520 $00 2250 0.02051 0.02009 11.918A 1,431.0 0.0 480.5 1,1853 555,842.3 372.8 ,

16,141.2 500 470 2250 0.02009 0.01951 1,938.0 0.0 650.7 1,836.0 572,634.2 540.5 470 450 2250 0.01951 0.01916 10,128.5 1,21 6.1 0.0 408.3 2,244 3 583,171.1 672A 450 448 2250 0.01916 0.01912 944.5 113.4 0.0 38.1 2,2823 584,153.7 683.1 _;

448 400 2250 0.01912 0.01842 21,737.6 0.0 2,609.9 341.0 2,6233 606,232.2 754.5 ;

RW5TFEED AND BLEED REQUIRED (OALLON5) 12,000 ,

400 400 2250 0.01842 0.01842 0.0 0.0 ' 0.0 0.0 3,657.9 607,266.8 1,053.1 !

400 370 2250 0.01842 0.01804 12,370.9 0.0 1,485.3 194.0 3,851.9 619,831.8 1,086.5 370 350 2250 0.01804 0.01781 7,744.2 0.0 ~ 929.8 121.5 3,773.4 627,697.4 1,106.7 350 350 350 0.02698 0.01912 6,774.3 0.0 8133 0.0 3,973.4 634,471.7 '

1,094.9 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 3,973.4 628,896.0 1,104.6 j ADD IN RHRS VOLUMB (ASSUMB BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,504.1 712,899.2 1,104.6 >

350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,837.1 734,458.6 1,151.4 !

-300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 286.9 5,124.0 753,038.7 1,189.7 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5,232.1 760,036.0 1,203.6 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109A 145.0 5,377.1 769,424.4 1,2 21.8 l TOTAL BAT VOLUME = 6,797.5 GALLONS 1: l TOTAL RWSTVOL 23,850.6 GALLONS I 27FB400 ABB Combustion Engineering Nuclear Services Page 87 of 167 e

i i

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSES CEN-602, REV.2 TABLE 2-33 SEQUOYAH PLANT COOLDOWN FROM 547"F TO 2007 BAT AT 4.00 W % BORIC ACID, RWST AT 2700 ppm HORON: PZR @ 0% POWER LEVEL AVG.SYS'IEMP PZR SPECIFIC VCLUME SliRINKAGE BATVOL RWSTVOL B/A T0rrAL IUTAL SYS. FINAL PRESS. MASS @ 70'F @ 70'F ADDED B/A MASS CONC.

(cu.ftJibm) 71 FF) TffF) (psia) Vi Vf Obm) (gations) (gallons) Obm) Obm) Obm) (ppm boron]

547 547 2250 1.00000 1.00000 0.0 0.0 0.0 0.0 0.0 525,254.9 0.0 547 535 2250 0.02125 0.02092 8,049.9 966.5 0.0 335.4 335.4 533/403 109.9 535 520 2250 0.02092 0.02055 9,433.4 1,132.6 0.0 393.1 728.5 543,466E 2343 520 500 2250 0.02055 0.02009 11pl8.8 1,431A 0.0 496 6 1,225.1 555,8822 3853 500 480 2250 0.02009 0.01969 10,933.0 1,312.6 0.0 455.5 1/B04 567,270.7 518.0 480 460 2250 0.01969 0.01933 10,3713 12452 0.0 432.1 2,112 2 578,074 2 639.0 460 454 2250 0.01933 0.01922 2,968.7 356.4 0.0 123.7 2,236.5 581,166.6 672E 454 450 2250 0.01922 0.01916 1,996.7 0.0 239.7 313 2,267.8 583,194.6 6792 450 420 2250 0.01916 0.01869 14p432 0.0 1/iB6.1 220 3 2,488.0 597,458.1 728.1 420 400 2250 0.01869 0.01842 8/i38.9 0.0 1/D7.2 135.5 2/123 4 606,232.5 756.6 RWST FEED AND BLEED REQUIRED (GALLONS) 12p00 400 400 2250 0.01842 0.01842 0.0 0.0 0.0 0.0 3,658.1 607,267 4 1 /15 3.2 400 385 2250 0.01842 0.01822 6,446.7 0.0 774.0 101.1 3,7592 613,814 2 1p70.7 385 370 2250 0.01822 0.01804 Sp242 0.0 7113 92.9 3,852 2 619/02.0 1,096 4 370 360 2250 0.01804 0.01792 4p15.6 0.0 482.1 63D 3,915.1 623,910.6 1p97.1 360 350 2250 0.01792 0.01781 3,7283 0.0 447.7 583 3,9 73.6 627/i97.7 1,106.8 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,973 4 634,471.9 1,095.0 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4) 0.0 3,973.6 628,896 2 1,104.7 ADDIN RIIRS VOLUME (ASSUME BORON CONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,504.4 712,899.4 1,104.7 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,8373 734,458 3 1,151.5 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 286.9 5,124 3 753/D9.0 1,189.7 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5,232 3 760/D63 1,2fD.6 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109E 145.0 5,3773 769,424.7 1,221.9 l TOTAL BAT VOLUME = 6,444.4 GALLONS l l TOTAL RWSTVOL 24,203.7 GALLONS l 27FB400 ABB Combustion Engineering Nudear Sendees Page 88 of 167

_ . _ - -.-. - _ ~ . . _ - . -

BORIC ACID CONCENTRATION REDUCTION CFFORT CEN-602, Cev.2 TECHNICAL BAS ~Y3 AND OPERATIONAL ANALYSES Table 2-34 Minimum Boration Volume from Boric Acid Tank vs.

Stored Boric Acid Concentration for Modes 1,2, and 3 Minimum volume (callons)

BAT BAT CONC. RWST RWST RWST RWST RWBT CONC. (wt% CONC. CONC. CONC. CONC. CONC.

(ppa Boron) Borio Acid) 2500 ppm 2550 ppm 2600 ppm 2650 ppm 2700 ppm 6120 3.50 8803.9 8640.6 8478.1 8258.9 8147.9 6340 3.625 8258.9 8092.6 7927.1 7760.5 7647.5 6560 3.75 7760.5 7647.5 7534.9 7310.7 7197.4 6775 3.875 7422.6 7254.9 7082.7 6968.3 6797.5 6990 4.00 7025.5 6911.3 6797.5 6624.0 6444.4 ABB Combustion Engineering Nuclear Services Page 89 of 167 J

BORIC ACID CONCENTRATION CEDUCTION CFFORT CEN-602, R;v.2 TECHNICAL BA523 AND OPERATIONAL ANALY C Table 2-35 Minimum Stored Boric Acid Tank Volume vs.

Stored Boric Acid Concentration for Modes 1,2, and 3 Minimum stored volume (Gallons)*

BAT BAT CONC. RWST RWST RW8T RW8T RWST CONC. (wt.% CONC. CONC. CONC. CONC. CONC. ;

(ppm Boron) Boric Acid) 2500 ppm 2550 ppm 2600 ppa 2650 ppm 2700 ppm 6120 3.5 9350 9150 9000 8800 8700 6340 3.625 8800 8600 8500 8300 8200 6560 3.75 8300 8200 8050 7850 7700 6775 3.875 7950 7800 7600 7500 7350 I 6990 4.0 7550 7450 7300 7150 6950

Stored BAT Volume equal to Boration Volume from Table 2-34 plus 500 gallons for conservatism, rounded up to the nearest 50 gallons. In some cases, an additional 50 gallons have been added to result in the same values contained in Revision 1.

i ABB Combustion Engineering Nuclear Services Page 90 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Table 2-36 Initial Conditions and Assumptions Used in the Modes 1,2, and 3 Calculation Xenon-Free scenario 3

a. Reactor Coolant System Volume 10,812 ft

b. Reactor Coolant System Pressure 2250 psia

c. Reactor Coolant System Temperature 547'F 3

c. Pressurizer volume (9 100% Power Level) 444.6 ft

d. Pressurizer is at Saturation -----

e. Reactor Coolant System Leakage 0

f. RCS Depresurization Performed as Shown -----

in Tables 2-39 through 2-63

g. Initial RCS Concentration 0 ppm boron

h. Initial PZR Concentration 0 ppm boron

i. Complete and Instantaneous Mixing -----

Between Pressurizer and RCS

j. Constant PZR Level Maintained, Charging -----

to Compensate for Coolant Contraction

k. Boron Concentration in RCS equal to -----

Concentration in RHRS at Time of .

Residual Heat Removal Initiation

1. Initial Feed & Bleed to 579 ppm -----

m. Boration Source Temperature -----

Refueling Water Storage Tank (RWST) 70 F Boric Acid Tank (BAT) 7 0*F !

l l

l ABB Combustion Engi;;eering Nuclear Services Page 91 of 167 ;

l

1 BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS r

Table 2-37 i Required Boron Concentration for a Cooldown From 547"F to 200 F Xenon Free Scenario Temperature Concentration

F (ppa boron) 547 579.0 ;

500 737.0 450 868.0 400 970.0 350 1047.0 300 1109.0 250 1163.0 '

200 1212.0 l

l l

ABB Combustion Engineering Nuclear Services Page 92 of 167

BORIC ACID CONCENTRATION REDUCTION CFFORT CEN-602, ROV.2

! TECHNICAL BA833 AND OPERATIONAL ANAI.YIE3 TABLE 2-38 SEQUOYAH - FEED-AND-BLEED @ 75 GPM FROM 0 ppm @ 2500 psia & 547'F TIME TO REACH FINAL CONCENTRATION OF 579 ppm BORON BAT CONC C(t) C(in) C(t)/C(in) 1-C(t)/C(in) In[1-(C(t)/C(in)) t BAT VOL.

wt% (minutes) (gallons) 3.500 579.0 6119.2 0.0946 0.9054 -0.0994 83.62 6269.0 3.625 579.0 6337.7 0.0914 0.9086 -0.0958 80.60 6042.0 3.750 579.0 6556.3 0.0883 0.9117 -0.0925 77.78 5831.3 3.875 579.0 6774.8 0.0855 0.9145 -0.0893 75.16 5634.0 4.000 579.0 6993.4 0.0828 0.9172 -0.0864 72.70 5451.0 ABB Combustion Engineering Nuclear Services Page 93 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-39 SEQUOYAH PLANT COOLDOWN FROM 54PF TO 200'F (XENON FREE) !

BAT AT 3.50 wt% BORIC ACID: RWST AT 2500 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PR ESS. MASS @ 707 @ 707 ADDED B/A MASS CONC (cu.ftAbm) r Ti(T) Tf(T) (pein) VI Vf Obm) (sallone) (saltone) Obe) Obm) Obe) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 6,269.0 0.0 - 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 171.8 1,917.0 531,908.2 630.1 540 523 2250 0.02106 0.02062 10,871.2 1,305.2 0.0 3943 2,311 3 543,173.7 744.0 523 500 2250 0.02062 0.02009 13,794.8 0.0 1,656.2 200.1 2,511.5 557,168.5 788.1 RWSTFEED AND BLEED REQUIRED (OALLONS)- 7,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,058.8 557,715.9 958.9 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,31 2.6 158.6 3,21 7.4 568,807.5 988.9 480 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 222.5 3,439.9 584,366.7 1,029.2 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 170.2 3,610.1 596,268.0 1,058.5 425 400 '2250 0.01877 0.01842 10,951.0 0.0 1,31 4.8 158.9 3,769.0 607,377.9 1,084.9 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 179.5 3,948.4 619,9283 1,113.5 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 1123 4,060.8 627,784.8 1,130.9 350 350 350 0.02698 0.01912 6,7743 0.0 813 3 0.0 4,060.8 634,559.1 1,118.8 350 350 350 0.01781 0.01797 (5,575.7) 0.0 . (669.4; 0.0 4,060.8 628,9833 1.128.7 ADD IN RHRS VOLUMB (ASSUMB BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 - 0.0 0.0 0.0 0.0 4,603.2 712,998.2 1,128.7

!- 350 300 350 0.01797 0.01743 21,226.4 0.0 2.548.5 307.9 4.911.1 734,532.6 1,168.9 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 265.4 5,176.5 753,091.2 1,201.7 l 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 99.9 5,276.4 764,0803 1,21 3.7 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 134.1 - 5,410.5 769,457.9 1,229.4 l TOTAL BAT VOLUME = 8,142.9 GALLONS l l TOTAL RWSTVOLUME 23,7742 GALLONS ]

- 25XFB500 ABB Combustion Engineering Nuclear Services Page 94 of 167 J

t 1

_ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ - _ _ _ _ _ _ _ - _ . _ _ . _ _ _ _ _ _ . - _ _ _ _ _ _ _ _~ie.-,-.e . - ~ ..-~..r.-.. -.,..,.r ~.,---..,,.-,.r- 4..--- -,.w .....-e.. . 4.-.-......n.%. ,_.-s- ,

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV,2 TABLE 2-40 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200"F (XENON FREE)

BAT AT 3.625 wt% BORIC ACID: RWST AT 2500 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUMB SHRINKAGB BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL .

PRESS. MASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (cu.ft/lbm)

Ti(7) Tf(T) (pala) VI Vf (Ibm) (antions) (tellons) (It m) (Ibe) (Ibe) (ppe boron) ;

- 547 547 2250 1.00000 1.00000 0.0 6,042.0 0.0 0.0 1,7453 527,000.2 579.0

, 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 178.1 1,923.4 531,914.5 632.2

' 9,628.0 1,156.0 0.0 362.1 2,285.6 541,904.6 737.4 540 525 2250 0.02106 0.02067 525 500 2250 0.02067 0.02009 15,038.0 0.0 1,805.5 218.2 2,503.7 557,160.8 785.6 RWSTFBBD AND BLBED RBQUIRED(GALLONS) 7,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,0 51.8 557,708.9 956.7 I

500 485 2250 0.02009 0.01979 8,1583 0.0 979.5 118.4 3,170.2 565,985.6 9793 2,174.5 584,359.7

485 450 2250 0.01979 0.01916 18,111.4 0.0 262.7 3,432.9 1,027.1 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 170.2 3,603.1 596,261.0 1,056.5

! 425 : 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 -158.9 3,762.0 607,370.9 1,082.9

400 370 2250 0.01842 0.01804 12,370.9 0.0 1,485.3 179.5 3,941.4 619,921 3 1,111.6

! 370 350 2250 0.01804 0.01781 7.744.2 0.0 929.8 1123 4,053.8 627,777.8 1,129.0

~i 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,053.8 634,552.1 1,116.9 3

628,9763 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 4,053.8 1,126.8 ,

ADD IN RHRS VOLUMB (ASSUMB BORO *f CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,595.2 712,990 3 1J 26.8 350 300 '350 0.01797 0.01743 21,226.4 0.0 2,548.5 307.9 4,903.2 734,524.6 IJ 67.1 300 250 350 0.01743 0.01699 18,293.2 0.0 , 2,1963 265.4 5,168.5 753,083.2 1,199.9 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 99.9 5,268.5 760,072.4 1,211.9 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 134.1 5,402.6 769,449.9 1,227.6 l TOTAL BAT VOLUME = 7,766.6 GALLONS l l TOTAL RWST VOLUME 23,923.5 GALLONS l 25XFB500 l

ABB Combustion Engineering Nuclear Services Page 95 of 167 4

4 l

1

V I

i 7

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-41 SEQUOYAH PLANT COOLDOWN FROM 54TF TO 200'F (XENON FREE)

B AT AT 3.75 wt% BORIC ACID: RWST AT 2500 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAOB BAT VOL RWST VOL B/A TOTAL TOTALSYS. FINAL PR ESS. MASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (cu.ftAbm)

Ti (*F) Tf(T) (pain) Vi Vf (Ibm) (gallons) (gallons) (Ibm) (Ibe) (Ibe) (ppeboron) 547 547 2250 1.00000 1.00000 0.0 5,831.3 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 184.5 1,929.8 531,920.9 6343

. 540 527 2250 0.02106 0.02072 8.390.6 1,007.4 0.0 326.9 2,256.7 540,638.4 729.8 527 500 2250 0.02072 0.02009 16.275.4 0.0 1,954.1 236.1 2,492.8 557,149.9 782.2 RWSTFEED AND BLEED REQUIRED (OALLONS) 7,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,042.0 557,699.1 953.6 j 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,312.6 158.6 - 3,200.6 568,790.7 983.8 480 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 222.5 3,423.1 $84,349.9 1,024.2 ,

450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 170.2 3,593 3 596,251.2 1,053.6

, 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 158.9 3,752.1 607,361.1 1,080.1 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,485.3 179.5 3,931.6 619,911.4 1,108.8 370 350 2250 0.01804 '0.01781 7,744.2 0.0 929.8 1123 4,043.9 627,768.0 IJ 26.2 350 350 350 0.02698 = 0.01912 6,774 3 0.0 8133 0.0 4,043.9 634,542.2 1,114.2 i 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 4,043.9 628,966.5 1,124.1 !

ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,584.1 712,979.1 1,124.1 ,

2 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 307.9 4,892.0 734,513.5 1,164.4 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 265.4 5,157.4 753,072.1 1,1973 1 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 99.9 5,257.3 760,061 3 1,209.3

230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 134.1 5,3 91.4 76,,438.8 1,225.1 I l TOTAL BATVOLUME = 7,407.3 GALLONS l l TOTAL RWST VOLUME 24,072.1 GALLONS l 25XFB500 l ABB Combustion Engineering Nuclear Services Page 96 of 167 !

4 a

i i

E i

4

. _ . . _ - _ _ _ _ . . . _ . . - . _ . _ _ __-_._.,,,1..-.- e. .+% m -. _. .y. .,....,,._am,,..,w_g., .,,,,,.,,,,,.m,-%-#-~.,,wn.y.,_%,-,,.m,c,._um,fm,,..,,w,..

BORIC ACID CONCENTRATION REDUCTION EFFORT ,

TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-42 SEQUOYAH PLANT COOLWN FROM 547'F TO 200'F (XENON FREE) l BAT AT 3.875 wt% BORIC ACID: F ^VST AT 2500 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUM E SHRINKAG E - BAT VOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70 7 @ 70 7 ADDED B/A MASS CONC.

(cu.fi/tbm)

Ti(T) Tf(T) (pain) VI Vf (Ibm) (sellone) (sallons) Obm) (Ibe) Obm) (ppe boron) 547 547 2250 1.00000 1.00000 0.0 5,634.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 190.9 1,936.2 531,927 3 636.4 540 '528 2250 0.02106 0.02074 7,774.1 933.4 0.0 313.4 2,249.6 540,014.8 7283 528 500 2250 0.02074 0.02009 16,891.9 0.0 2,028.1 245.0 2.494.6 557,151.7 782.6 RWSTFEED AND BLEED REQUIRED (OALLONS) 7,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,043.6 557,700.7 954.2 500 470 2250 0.02009 0.01951 16,141.2 0.0 1,938.0 234.2 3,277.8 574,076.1 998.2 i

470 460 2250 0.01951 0.01933 5,163.1 0.0 619.9 74.9 3,352.7 579.314.1 1,011.8 460 450 2250 0.01933 0.01916 4,965.4 0.0 596.2 72.0 3,424.7 584,351.5 1,024.7 450 400 2250 0.01916 0.01842 22,682.1 0.0 2,7233 ~ 329.0 3,753.8 607,362.7 1,000.6 l

400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 179.5 3,933.2 619,913.1 1,1093 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 1123 4,045.6 627,769.6 1,126.7

{ 350 '350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,045.6 634,543.9 1,114.7 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4' O.0 4,045.6 628,968.2 1,124.5 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 ' 0.01797 0.01797 0.0 0.0 0.0 0.0 4,586.0 712,981.0 IJ 24.5 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 307.9 4,893.9 734,515.4 1,164.9 300 250 350 ' O.01743 0.01699 18,293.2 0.0 2,1963 265.4 5,1593 753,074.0 IJ97.8 I

250 230 -350 0.01699 0.01683 6,899.2 0.0 827.1 99.9 5,259.2 760,063.1 1,209.8 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 134.1 5,393.3 769,440.7 1,225.5 t

l TOTAL BATVOLUME -= 7,136.0 GALLONS - l l TOTAL RWST VOLUME 24,146.1 GALLONS l i 25XFB500 ABB Combustion Engineering Nuclear Services Page 97 of 167 'I 4

i 1

i

_ . _ . - _ _ _ _ _ _ _ . . _ _ _ . _ . _ _ _ - . _ - - . _ . ._.._.___.2.~.-. . . . . _ , . _ , . _ - _ _ . . . ~ . - - . . . _ . _ . _ . - . _ - . . . . _ . _ . _ . . . - - . _ _ _ _ _-____ _ ___ a

l BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 l

l TABG 2-43 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200F (XENON FREE)

BAT AT 4.00 wt% BORIC ACID; R%7T AT 2500 ppm BORON: PZR @ 0% POWER LEVEL AVG.SYS TEMP PZR SPECIFIC VOLUME SIDUNKAGE BAT VOL RWSTVOL IVA TUTAL 'IUTAL SYS. FINAL PRESS. MASS @ 70'F @ 70'F ADDED IVA MASS CONC (cu.ftJttwn)

TicF) TYPF) (psia) Vi Vf (Ibm) (gallons) (gasons) (Itwn) (Ibm) (! tun) (ppm txxon] ,

547 547 2250 1.00000 1.00000 0.0 5,451D OD OD 1,7453 527,000 2 579.0 547 5% 2250 0.02125 OD2079 11,281.7 1,3543 0.0 470.1 2,2153 538,751 3 7183 530 520 2250 0.02U79 0.02055 6,201.7 OD 7446 90D 2,3053 545,0434 739.5 520 500 2250 0.02055 0.02009 11,918E 0.0 1,431D 172.9 2,478.2 557,1353 777.7 RW5T FEED AND BLEED REQUIRED (GALLONS) 7,000 500 500 2250 0.02009 OD2009 0.0 0.0 OD OD 3,028E 949.5 5574859 500 480 2250 0.02009 0.01969 .10,933.0 0.0 1,312E 1584 3,187.4 568,777.5 979E 480 460 2250 OD1969 OD1933 10,3713 OD 1,245.2 150.5 3,337 3 579,2993 1 /10 7.4 460 450 2250 0.01933 0.01916 4,965.4 OD 596.2 72D 3,4093 584,336.7 1,020.2 450 445 2250 OD1916 0.01908 2,367 3 0.0 284.2 343 3,444 3 586,7383 1,026 3 445 420 2250 0.01908 OD1869 11,676.0 0.0 1,401E 169.4 598,583.7 34134 1 #55.5 420 400 2250 021869 0.01842 8,638.9 0.0 1,037.2 1253 3,739D 607,347.9 1 # 76 3 400 385 2250 021842 OD1822 6,446.7 OD 774D 93.5 3,8323 613,888.1 1,0 91.5 385 370 2250 OD1822 OD1804 5,924.2 OD 711 3 85.9 3,918.4 619,898 3 1,105.1 370 360 2250 0.01804 OD1792 4,0154 OD 482.1 583 3,976.7 623,9723 1,114.2 360 350 2250 OD1792 0D1781 3,728.5 0.0 447.7 54.1 4,030.8 627,754 3 1,1224 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 OD 4,030E 634,529.1 1,1104 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; OD 4,030E 628,9533 1,120.5 ADD IN RHRS VOLUME (ASSUM E BORON CONC = RG BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 OD OD 4,569.2 712,964.2 1,120.5 350 300 350 OD1797 0.01743 21,226.4 0.0 2,548.5 3079 4,877.1 734,498E 1,160.9 300 250 350 0.01743 OD1699 18,293.2 - 0.0 2,1963 265.4 5,142.5 753,057.2 1,193.9 250 230 350 0.01699 OD1683 6,889.2 OD 8Z7.1 999 5,242.4 .760,0463 1,205.9 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109E 134.1 5,376.5 769,4233 1,2 21.7

[ TOTAL BAT VOLUME = 6,805.5 GALLONS l l TOTAL RWST VOLUME = 24,293.6 GALLONS l 25XFB500

[ABB Combustion Engineering NuclearServices Page 98 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-44 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F (XENON FREE)

BAT AT 3.50 wt% BORIC ACID: RWST AT 2550 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @707 @ 70 7 ADDED B/A MASS CONC (cu.fi/lbe)

Ti(T) Tr(T) (pain) Vi Vf Obm) (sellone) (sellone) Obe) Obe) Obe) (ppe boros) 547 547 2250 1.00000 1.00000 0.0 6,269.0 0.0 0.0 1.7453 527,000.2 579.0 547 $40 2250 0.02125 0.02106 4,736.2 568.6 0.0 171.8 1,91 7.0 531,908.2 630.1 540 . 525 2250 0.02106 0.02067 9,628.0 1,156.0 0.0 349.2 2,266.3 541,885.3 731.2 525 500 2250 0.02067 0.02009 15,038.0 0.0 1,805.5 222.6 2,488.8 557.145.9 781.0 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,750 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,035.2 557,692.3 951.5 500 480 2250 -0.02009 0.01969 10,933.0 0.0 1,3116 161.8 3,197.0 568,787.1 982.7 r 4A0 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 227.0 3,424.0 584,350.8 1,024.4 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 173.6 3,597.7 596,255.6 1,054.9 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,31 4.8 162.1 3,759.7 607,368.7 1,082.3 400 370 2250 0.01842 0.01804 12.370.9 0.0 1,485.3 183.1 3,942.9 619,922.7 1,112.0 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 114.6 4,057.5 627.781.5 1,130.0 350 350 350 0.02696 0.01912 6,774.3 0.0 813.3 0.0 4,057.5 634,555.8 1,117.9 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,057.5 628,980.1 1,127.8

, ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC)

, 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,599.4 712,994.5 1,127.8 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 314.2 4,913.6 734,535.1 1,169.5 300 250 350 0.01743 0.01699 18,293.2 0.0 2,196.3 270.8 5,184.4 753,099.1 1,203.6 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 102.0 5,286.3 760,090.3 1,21 6.0 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 136.8 5,423.2 .

769,470.5 1,232.2 i l TOTAL BATVOLUME = 7,993.6 GALLONS l l TOTAL RWST VOLUME 23,673.5 GALLONS l 255XFB50 ABB Combustion Engineering Nuclear Services PaQe 99 of 167 4

1 5

k e

_ _ _ _ . _ . . _ . _ _ _ . _ _ _ . _ ._m._.__..mm__._m.m_____.__._. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

___ - -

r -.. . - ~ . , , ~ --,.m. _ _ , ,w ,...m., ..,.,,,,_..---...%...,-m-.--. _~.w.-..ww .. . . , - . . -

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-45 SEQUOYAH PLANT COOLDOWN FROM 54PF TO 200'F (XENON FREE)

B AT AT3.625 wt% BORIC ACID: RWST AT 2550 ppm BORON PZR @ 0% POWER LEVEL AVO.S YS. TEM P PZR SPECIFIC VOLUME SliRINKAOE BAT VOL RWST VOL B/A TOTAL TOTAL 5YS. FINAL PRESS. MASS @ 70"F @ 70 7 ADDED B/A MASS CONC (ca.ftJIbm)

Ti(T) Tf(T) (pale) Vi Vf Obm) (gallone) (gallone) Obm) Obm) Obm) (ppe boros) 547 547 2250 1.00000 1.00000 0.0 6,042.0 0.0 0.0 1,7453 527,000.2 579.0 547 340 2250 0.02125 0.02106 4,736.2 568.6 0.0 178.1 1,923.4 531,914.5 632.2 540 526 2250 0.02106 0.02069 9,008.6

1,081.6 0.0 338.8 2,2623 541,261.9 730.7 526 500 2250 0.02069 0.02009 15,657.4 0.0 1,879.9 231.7 2,494.0 557,151.1 782.6 RWSTFEED AND BLBED REQUIRED (OALLONS) 6,750 500 Soo 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,039.9 557,677.0 953.0 500 485 2250 0.02009 0.01979 8,1583 0.0 979.5 120A 3,160.6 565,976.0 9763 485 450 2250 0.01979 0.01916 18,111.4 0.0 2,174.5 268.1 3,428.7 584,355.5 1,025.8 450 425 .2250 0.01916 0.01877 11,731.1 0.0 1,408.5 173.6 3,6023 596,260 3 1,056 3

- 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314 A 162.1 3,764.4 607,373.4 1,083.6 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 183.1 3,947.5 619,927.4 1,1133 370 350 2250 0.01804 0.01781 7,744.2 0.0 929A 114.6 4,062.2 627,786.2 1,131.3 350 350 350 0.02696 0.01912 6,7743 0.0 8133 0.0 4,062.2 634,560.4 1,119.2 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 4,062.2 628,984.7 1,129.1 ADD IN RHRS VOLUMB (A55UMB BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,604.7 712,999.8 1,129.1 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 314.2 4.918.9 .734,540.4 1,170.8 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 270.8 5,189.7 753,104.4 1,204.8 j 250 '230 350 0.01699 0.01683 6,889.2 0.0 827.1 102.0 5,291.6 760,095.6 1,21 7.2 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 136A 5,428.5 769,475.8 1,233.4 I

l TOTAL BATVOLUME = 7,692.2 GALLONS l l TOTAL RWSTVOLUME 23,747.9 GALLONS l 255XFB50 ABB Combustion Engineering Nuclear Services Page 100 of 167 i

1

, , . ,, , .. ,- ,.~.-..-..-,m_.__- __ _ _______mm -

_____,m -~. , , .,,-.--m..__. .-r__-_ _ . - _ . , - . - _ _ _ _ . - .

-,_m

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 ,

TABLB 2-46 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200'F (XENON FREE)

BAT AT 3.75 wt% BORIC ACID: RWST AT 2550 ppm BORON: PZR 9 0% POWER L EVEL AVO.SYS. TEM P PZR SPECIFIC VOLUMB SHRINKAOB BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (cu.ft/tbm)

Ti(7) Tf(T) (pain) VI Vf (Ibm) (gallone) (gallons) (Ibe) (Iba) (Iba) (ppeboros) 547 547 2250 1.00000 1.00000 0.0 5,831 3 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 184.5 1,929.8 531,920.9 6343 540 530 2250 - 0.02106 0.02079 6,545.5 785.9 0.0 255.0 2.184E 538,721.4 709.0 530 500 2250 0.02079 0.02009 18,120.5 0.0 2,175.6 268.2 2,453.0 557,110.1 769E RWSTFEED AND BLBED REQUIRED (OALLONS) 6,750 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,002A 557,659.9 941.4

500 480 2250 0.02009 0.01969 10,933.0 0.0 1,312.6 161.8 3,164.6 568,754.7 972.8 480 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 227.0 3.391.6 584,318.4 1,014A 450 425 2250 0.01916 - 0.01877 11.731.1 0.0 1,408.5 173.6 3,565.2 596,223.2 1,045.5 4

425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 162.1 3,7273 607,3363 1,073.0 l 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 183.1 3,91 0.4 619,890 3 1,102.9 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 114.6 4,025.0 627,749.1 1,121.0 j 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 4,025.0 634,5233 1,109.0 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 4,025.0 628,947.6 1,118.9 ADD IN RHRS VOLUMB (ASSUMB BORON CONC = RCS BORON CONC) i 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,562.7 712,957.7 1,118.9

350 300 350 0.01797 0.01743 21,226.4 S.0 2,548.5 314.2 4,876.9 734,4983 1,160.8

} 300 250 350 0.01743 0.01699 18,293.2 0.0 2,196.3 270E 5,147.6 753,0623 1,195.1 i 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 102.0 5,249.6 760,053.5 1,207.6 4

230 200 350 0.01683 0.01662 l 9,243.4 0.0 1,109.8 136.8 5,386.4 769,433A 1,223.9 i

4 l TOTAL BATVOLUME = 7,185.8 GALLONS l l TOTAL RWST VOLUME 24,043.6 GALLONS l 255XF850 i ABB Combustion Engineering Nuclear Services PaDe 101 of 167 i

i t

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLB 2-47 SEQUOYAH PLANT COOLDOWN FROM 54TF TO 200*F (XENON FREE)

B AT AT3.875 wt% BORIC ACID: RWST AT 2550 rpm BORON PZR @ 0% POWER LEVEL

_ AVO.S YS. TEM P PZR SPECIFIC VOLUMB SHRINKAOB BAT VOL RWST VOL B/A 70TAL TOTALSYS. FINAL PR ESS. MASS @ 70 7 @ 707 ADDED B/A M ASS CONC (cu.ftjtbm)

Ti(T) Tf(T) (psis) VI Vf (Ibm) (gallons) (gallons) (Ibm) (Ibm) (Ibm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 5,634.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 190.9 1,936.2 531,927 3 636.4 540 530 2250 0.02106 0.02079 6,545.5 785.9 0.0 263.9 2,200.1 538,736.7 714.0 530 500 2250 0.02079 0.02009 18,120.5 0.0 2,175.6 268.2 2,4683 557,1253 774.6 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,750 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 3,016.6 557,673.7 945.7 500 470 2250 0.02009 0.01951 16,141.2 0.0 1,938.0 238.9 3,255.5 574,053.8 991.5 470 460 2250 0.01951 0.01933 5,163.1 0.0 619.9 76.4 3,331.9 579,2933 1,005.6 460 450 2250 0.01933 0.01916 4,965.4 0.0 5%.2 73.5 3,405.4 584,332.2 1,01 8.9 450 400 2250 0.01916 0.01842 22,682.1 0.0 2,7233 335.7 3,741.1 607.350.1 1,076.9 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,485.3 183.1 3,924.2 619,904.1 1,106.8 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 114.6 4,038.8 627,762.9 1,1 24.8 350 350 350 0.02698 0.01912 6,774.3 0.0 8133 0.0 4,038E 634,537.1 1,112.8 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4j 0.0 4,038.8 628,961.4 1,122.7 ADD IN RHRS VOLUMB (ASSUMB BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,578.3 712,973.4 1,122.7 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 314.2 4,892.5 734,514.0 1,164.5 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1%.3 270E 5,1633 753,078.0 1,1 98.7 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 102.0 5,265.2 760,069.2 1,211.1 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 136.8 5,402.0 769,449.4 1,227.5 l TOTAL BATVOLUME = 6,988.5 GALLONS l l TOTAL RWSTVOLUME 24,043.6 GALLONS l 255XFB50 ABB Combustion Engineering Nuclear Services Page 102 Of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABG 2-48 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200F (XENON FREE)

BAT AT 4.00 wt% BORIC ACID: RWST AT 2550 ppm BORON: P7R @ 0% POWER LEVF1 AVO.SYSJ11N P PZR SPEC 114C VOLUME S11RINKAGE BATVOL RWSTVOL 11/A TUTAL ~1UTAL SYS. 11NAL PRESS. MASS @ 70'F @ 70'F ADDED B/A MASS CONC.

(cu.fi)1bm)

TICF) "ITPF) (psis) VI Vf (Ibm) (ganons) (gnDons) (Itm) (Ibm) (Ibm) (ppn boron:

547 547 2250 1D0000 1.00000 0.0 5,4 51.0 OD 0.0 1,745 3 527,000.2 579D 547 532 2250 OD2125 0.02084 9,959.2 1,195.7 0.0 415D 2,160.2 537,374.4 7023 532 520 2250 OD2084 0.02055 7,524.1 0.0 903.4 111.4 2,271 4 545,009.9 72fL7 520 500 2250 OD2055 0.02009 11,918E 0.0 1,431D 176.4 2,448D 557,105.1 7683 RWSr FEED AND BGED REQUIRED (GALLONS) 6,750 500 500 2250 OD2009 0.02009 0.0 0.0 0.0 OD 2,998 2 557,6553 940D 500 480 2250 0.02009 0.01969 10,9310 0.0 1,31 2.6 161E 3,160.1 568,750.2 9 71.4 480 460 2250 OD1969 0.01933 10,3713 0.0 1,245.2 153.5 3,3134 579,275.0 1,000.1 460 450 2250 OD1933 0.01916 4,965.4 0.0 596.2 733 3,387.1 584,313.9 1,013.5 450 445 2250 0.01916 0.01908 2,3673 0.0 284.2 35D 3,422.1 586,716.2 1,019.7 445 420 2250 om908 0D1869 11,676.0 0.0 1,401.8 1723 3,594.9 598,565.0 1,050.0 420 400 2250 0.01869 0.01842 8,638.9 0.0 1,037.2 127.9 3,7228 607,331.7 1,0 71.7 400 385 2250 0.01842 0.01822 6,446.7 0.0 774D 95.4 3,81tL2 613,873E 1,087.4 385 370 2250 OD1822 0D1804 5,924.2 OD 711 3 tr7.7 3,905.9 619,885.7 1,1014 370 360 2250 OD1804 0.01792 4,015.6 0.0 482.1 59.4 3,9653 623,960 2 1,111.1 3rio 350 2250 0D1792 OD1781 3,728.5 0.0 447.7 55.2 4,020 3 627,744.5 1,119E 350 350 350 DD2698 0.01912 6,7743 0.0 8133 0.0 4,020.5 634,518E 1,107E 350 350 350 0.01781 0D1777 (5,575.7; 0.0 (669.4; 0.0 4,020.5 628,943.1 1,1174 ADD IN RIIRS VOLUME (ASSUME BORON CDNC. = RCS BORON CONC.)

350 350 350 0.01777 0.01777 0.0 0.0 OD 0.0 4,557 3 712,9524 1,1174 350 300 350 021797 0.01743 21,226.4 0.0 2,5483 314.2 4,8 71.7 734,4912 1,159 4 300 250 350 OD1743 0.01699 18,2912 0.0 2,1%3 270E 5,142.5 753,057.2 1,1919 250 230 350 0D1699 OD1683 6,889.2 0.0 827.1 102.0 5,244.5 760,048.4 1,206.4 230 200 350 OD1683 0.01662 9,2414 0.0 1,109E 136E 5,381 3 769,4284 1,222E l TOTAL BAT VOLUME = 6,646.7 GALLONS l l TOTAL RWST VOLUME = 24,202.4 GALLONS l 255XFB50 ABB Combustion Engineering NuclearServices Page 103 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-49 SEQUOYAH PLANT COOLDOWN FROM 54PF TO 200*F (XENON FREE)

BAT AT 3.50 wt% BORIC ACID: RWST AT 2600 ppm BORON: PZR @ 0% POWER LEVEL 1 AVO.SYS. TEM P PZR SPECIFICVOLUMB SHRINKAOB BAT VOL RWST VOL B/A TOTAL TOTALSYS. FINAL PR ESS. M ASS @ 70 7 @ 707 ADDED B/A MAS $ CONC (ca.ft/ Ibm)

Ti(T) Tf(T) (paia) VI Vf Obm) (sallone) (nelloos) (Ibe) Obe) Obs) (ppe boron) 547 547 2250 1.00000 1.00000 0.0 6,269.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 171.8 1,917.0 531,908.2 630.1 540 527 2250 0.02106 0.02072 8,390.6 1,007.4 0.0 304.3 2,221.4 540,603.1 718.4 527 500 2250 0.02072 0.02009 16,275.4 0.0 1,954.1 245.7 2,467.1 557,124.1 774.2 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,250 i

500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,991.1 557,648.1 937.8 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,3116 165.0 3,156.1 548,746.2 970.2 480 450 2250 0.0196) 0.01916 15,336.7 0.0 1,841.4 231.5 3,387.6 584,314.4 1,013.6 i 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 177.1 3,564.7 596,222.7 1,045.3 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 1653 3,730.0 607,339.0 1,073.8 l 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 186.7 3,916.8 619,896.6 IJ 04.7 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 116.9 4,033.7 627,757.7 1,123.4 350 350 350 0.02698 0.01912 6.774.3 0.0 8133 0.0 4,033.7 634,532.0 1,111.4 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 4,033.7 628,956.3 1,1213 ADD IN RHRS VOLUMB (ASSUMB BORON CONC = RCS BORON CONC) !

a 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,572.5 712,967.5 1J 21.3 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 320.4 4,892.9 734,514.4 1,164.6 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 276.1 5,169.1 753,083.8 1,200.0

! 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104.0 5,273.1 760,077.0 1,21 2.9 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 139.5 5,412.6 769,440.0 1,229.8 l TOTAL BAT VOLUME = 7,845.0 GALLONS l l TOTAL RWSTVOLUME 23,322.1 GALLONS l 26XFB500 ABB Combustion Engineering Nuclear Services PaDe 104 of 167 k

i r

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

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLB 2-50 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F (XENON FREE)

DAT AT3 625 wt% DORIC ACID: RWST AT 2600 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SIIRINKAGE BATVOL RWST YOL B/A TOTAL TOTALSYS. FINAL PR ESS. M ASS @ 70 7 @ 707 ADDED B/A MASS CONC (ca.ft/tbm)

Ti(T) Tf (T) (psis) VI Vf Obm) (gallons) (gallons) Obm) (Ibm) (Ibm) (ppe boron) 547 547 2250 1.00000 1.00000 0.0 6,042.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4.736.2 568.6 0.0 178.1 1,923.4 531,914.5 632.2 540 528 2250 0.02106 0.02074 7,774.1 933.4 0.0 292.4 2,215A 539,981.0 717.4 528 500 2250 0.02074 0.02009 16,891.9 0.0 2,028.1 255.0 2.470.8 557.127.9 775.4 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,250 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,994.5 557,651.6 938.8 500 485 2250 0.02009 0.01979 8,1583 0.0 979.5 123.2 3,117.7 565,933.1 963.1 485 450 2250 0.01979 0.01916 18,111.4 0.0 2,174.5 273.4 3.3 91.1 584,317.9 1.014.6 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 177.1 3,568.2 596,226.1 1,046 3 425 400 2250 0.01877 0.01842 10,951.0 0.0 1.31 4.8 1653 3,733.5 607,342.4 1,074.7 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 186.7 3,920.2 619,900.1 IJ05.6 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 116.9 4,037.1 627,761.1 1,124.4 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 4,037.1 634,535.4 1.1123 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,037.1 628,959.7 1,122.2 ADD IN RIIRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0,01797 0.01797 0.0 0.0 0.0 0.0 4,576.4 712,971.4 1,122.2 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 320.4 4,896 2 734,518 3 1,165.6 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 276.1 5,172.9 753,087.6 1,200.9 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104.0 5,276.9 760,080.9 1,21 3.8 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109 A 1395 5,416.5 769,463.8 1,230.7 l TOTAL BAT VOLUME = 7,544.0 GALLONS l l TOTAL RWSTVOLUME 23,396.1 GALLONS l 26XFB500 ABB Combustion Engineering Nuclear Services Page 105 of 167

_. . - _ _ . _ . _ . - _ . - . _ . . . _ . ~ . - - _ _ _ - . - - - - - - - - _.._.-.m _. ~. ...._.-......,-....~.--._..-m._

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLB 2-51 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F (XENON FREE)

BAT AT 3.75 wt% BORIC ACID: RWST AT 2600 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAGE BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PR ESS. MASS @ 70 7 @ 707 ADDED B/A MASS CONC (cu.ft/lbm)

Ti(T) Tf(T) (psie) VI Vf (Ibm) (gallons) (gallone) (Ibs) (Iba) (Ibs) (ppeboron) 547 547 2250 1.00000 1.00000 0.0 5.831.3 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 184.5 1,929.8 531,920.9 634.3 540 532 2250 0.02106 0.02084 5,223.1 627.1 0.0 203.5 2,133.3 537,347.5 694.1 332 500 2250 0.02084 0.02009 19,442.9 0.0 2,334.4 293.5 2,426.8 557,083.9 761.6 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,250 Soo 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,9543 557,611.4 926 3 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,312.6 165.0 3,119.4 568,709.5 959.0 480 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 231.5 3,350.9 584,277.7 1,002.7 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 177.1 3,528.0 596,185.9 1,034.6 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,31 4.8 1653 3,6933 607,302.2 1,0633 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 186.7 3,880.1 619,859.9 1,094.4 j 370 350 2250 0.01804 0.01781 7.744.2 0.0 929.8 116.9 3,997.0 627,721.0 1,113.2 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 3,997.0 634,4953 1,101.4 350 350 350 0.01781 0.01797 (5.575.7] 0.0 (669.4; 9.0 3,997.0 628,919.6 1,111.1 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,530.9 712,925.9 1,111.1 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 320.4 4,851 3 734,472.7 1,154.8 i 300 250 350 . 0.01743 0.01699 18,293.2 0.0 2,1963 276.1 5,127.4 753,042.1 1,190.4 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104.0 5,231.4 760,035.4 1,203.4

'230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 139.5 5.371.0 769,418 3 1,220.4 I TOTAL BAT VOLUME = 7,027.0 GALLONS l l TOTAL RWSTVOLUME 23,702.4 GALLONS l 26XFBS00 -l ABB Combustion Engineering Nuclear Services PaDe 106 of 167 I

i

BORIC ACID CONCENTRATION REDUCTION EFFORT .

TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-52 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200"F (XENON FREE)

BAT AT3.875 wt% BORIC ACID: RWST AT 2600 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAOB BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. M ASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (cu.It/lbm)

Ti(T) Tf(T) (paio) VI Vf (Ibm) (talions) (gallons) (Ibm) (Ibm) (Ibm) (ppe boron) 547 547 2250 1.00000 1.00000 0.0 5,634.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 190.9 1,936.2 531,927 3 636.4 532 2250 0.02106 0.02084 5,223.1 627.1 0.0 210.6 2,146.7 537,360.9 698.5 540 532 500 2250 0.02084 0.02009 19,442.9 0.0 2,334.4 293.5 2,440 3 557,0973 765.8 6,250 RWSTFEED AND BLBED REQUIRED (OALLONS) 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,966.6 557,623.7 930.1 500 500 470 2250 0.02009 0.01951 16,141.2 0.0 1,938.0 243.7 3,2103 574,004.6 977.8 470 460 2250 0.01951 0.01933 5.163.1 0.0 619.9 77.9 3,288.2 579,249.6 992.5 460 450 2250 0.01933 0.01916 4,965.4 0.0 596.2 75.0 3,363.2 584,290.0 1,0063 450 400 2250 0.01916 0.01842 22,682.1 0.0 2,7233 342 4 3,705.6 607,314.5 1,066.8 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 186.7 3,8923 619,872.2 1,097.8 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 116.9 4,009.2 627,7333 1,116.6 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,009.2 634,507.5 1,104.7 350 350 350 0.01781 0.01797 (5,575.7] 0.0 (669.4; 0.0 4,009.2 628,931.8 1,114.5 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,544.8 712,939.8 1,114.5 2

350 300 350 0.01797 0.01743 21.226.4 0.0 2,548.5 320.4 4,845.2 734,486.7 IJ 58.1 1 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 276.1 5,1413 753,056.0 1,193.6 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 104.0 5,2453 760,049 3 1,206.6 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 139.5 5,384.9 769,432.2 1,223.6 l TOTAL BATVOLUME = 6,829.7 GALLONS l [ TOTAL RWST VOLUME 23,702.4 GALLONS l 26XFB500 ABB Combustion Engineering Nuclear Services Page 107 of 167 4

i l

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-53 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F (XENON FREE)

HAT AT4.00 wt% BORIC ACID; RW5T AT 2MO ppm BORON: P7R @ 0% POWER llIVEL AVG.SYSJEMP PZR SPECIFIC VOLUME SilRINKAGE BATVOL RW5TVOL IVA ivlAL iviALSYS. FINAL PRESS. MASS @70'F @ 7(PF ADDED BtA MASS CONC (cu.ftJttm)

Tr(*F) (psia) Vi Vf (Itm) (ganons) (gallons) (Ibm) (Itm) (Itm) (ppm bomn]

71('F) 547 547 2250 1.00000 1.00000 0.0 5,451D 0.0 OD 1,7453 527,000.2 579D 547 534 2250 0.02125 OD2090 8,643.5 1,0373 OD 360.1 2,105.4 536,0019 686.7 534 520 2250 0.02090 OD2055 8,839E OD 1,061 3 1314 2,2383 544pn.2 718.2 520 500 2250 0.02055 0.02009 11,918.8 0.0 1,431D 1793 2,418E 557,075 3 759.1 RW5TFEED AND BIlIED REQUIRED (GALLONS) 6,250 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 OD 2,947D 557/iO4.1 924D 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,31 2.6 165.0 3,112.1 568,702.2 956.7 480 4M) 2250 0.01969 0.01933 10,3713 OD 1,245.2 1564 3,2684 579,230.1 9864 460 450 2250 0.01933 0.01916 4,965A 0.0 596.2 75D 3,3434 584,270A 1,000.5 450 445 2250 0D1916 0.01908 2,367 3 0.0 284.2 35.7 3,3793 586,673A 1,007.1 445 420 2250 0D1908 0.01869 11,676D OD 1,401E 1763 3,555 4 598,5254 1,038 4 420 400 2250 0.01869 0.01842 8,638.9 0.0 1,037.2 130A 3,686D 607,294S 1,061.2 400 385 2250 0.01842 0.01822 6,446.7 OD 774D 773 3,7813 613B383 1,0774 385 370 2250 0 21822 0.01804 5,924.2 OD 711 3 89A 3,872E 619,852 4 1,0923 370 360 2250 0.01804 0.01792 4,0154 OD 482.1 604 3,9314 623,928E 1,102.2 3N) 350 2250 0.01792 0.01781 3,728.5 0.0 447.7 563 3,989.7 627,7117 1,111.2 350 350 350 0.02698 0.01912 6,7743 OD 8133 OD 3,989.7 634,4873 1,099A 350 350 350 0.01781 0.01777 (5,575.7; OD (669A; OD 3,989.7 628,912.2 1,109.1 ADD IN RHRS VOLUME (ASSUME BORON CDNC = RCS BORON CONC) 350 350 350 0.01777 OD1777 OD 0.0 04 OD 4,5224 712,917 4 1,109.1 350 300 150 021777 OD1743 21,226A OD 2,548.5 320A 4,8434 734,464.5 1,152.8 300 250 350 0.01743 0.01699 18,2912 0.0 2,1963 276.1 5,119.1 753,0333 1,188.5 250 230 350 0.01699 0.01683 6,889.2 OD 827.1 104D 5,2211 760,027.1 1,201.5 230 200 350 0.01683 OD1662 9,2414 CD 1,109E 139.5 5,362.7 769,410D 1,2184 l TOTAL BAT VOLUME = 6,488.8 GALLONS l l TOTAL RWST VOLUME = 23,860.3 GALLONS l 265XFB50 ABB Combustion Engineering NuclearServices Page 108 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, FlEV,2 TABLE 2-54 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200'F (XENON FREE)

BAT AT 3.50 wt% BORIC ACID: RWST AT 2650 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUMB SIIRINKAGE BAT VOL RWST VOL B/A TOTAL TOTALSYS. FINAL PR ESS. MASS @ 70 7 @ 70 7 ADDED B/A MASS CONC.

(cu.ft11bm)

Ti(7) Tf (7) (peis) Vi l Vf Obm) (gallone) (gallone) (Ibm) (Ibm) Obm) (ppm boron) 547 547 2250 1.00000' 1.00000 0.0 6,269.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125' O.02106 4,736.2 568.6 0.0 171.8 1,91 7.0 531,908.2 630.1 540 530 2250 0.02106 0.02079 6,545.5 785.9 0.0 237.4 2,154.5 538,691.0 699.2 530 500 2250 0.02079 0.02009 18,120.5 0.0 2,175.6 278.9 2,4333 557,090.4 763.7 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,954.0 557,611.0 926.2 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,312.6 1683 3,122.2 568,7123 959.8 480 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 236.0 3,3!83 584,285.1 1,004.9 450 425 2250 0.01916 0.01877 11,731,1 0.0 1,408.5 180.5 3,538.8 596,196.7 1,037.8 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 168.5 3,707.4 607,3163 1,0673 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 190,4 3,897.8 619,877.6 1,099.3 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 119.2 4,01 6.9 627,741.0 1,118.8 350 350 350 0.0269tt 0.01912 6,774 3 0.0 8133 0.0 4,016.9 634,515.2 1,106.8 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,01 6.9 628,939.5 1,116.6 ADD IN RIIRS VOLUMB (ASSUMB BORON CONC, = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 C.0 0.0 0.0 4,553.5 712,948.5 1,116.6 350 300 350 0.01797 0.01743 21.226.4 0.0 2,548.5 326.7 4,880.2 734,501.6 1,161.6 300 250 350 0.01743 0.01699 18,293.2 0.0 2,196.3 281.5 5,161.7 753,076.4 1,1983 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 106.0 5,267.7 760,071.7 1,211.7 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 142.3 5,41 0.0 769,457.4 1.229.2 ITOTAL BATVOLUME = 7,623.5 GALLONS l l TOTAL RWSTVOLUME 23,293.6 GALLONS l 265XFB50 ABB Combustion Engineering Nuclear Services Page 109 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-55 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200'F (XENON FREE)

BAT AT 3.625 wt% BORIC ACID: RWST AT 2650 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SIIRINKAOB BATVOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRESS. M ASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (ca.ftAbm)

Ti(7) Tf(7) (psis) VI Vf (Ibm) (gs!!ons) (gallons) (Ibm) (1bm) (1bm) (ppm boroe) 547 547 2250 1.00000 1.00000 0.0 6,042.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 178.1 1,923.4 531,914.5 632.2 540 531 2250 0.02106 0.02082 5,883.4 706.4 0.0 221 3 2,144.7 538,0193 696.9 531 500 2250 0.02082 0.02009 18,782.5 0.0 2,255.1 289.1 2,433E 557,090.9 763E RWSTFEED AND BLEED REQUIRED (OALLONS) 6,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,954.4 557,611.4 9263 500 485 2250 0.02009 0.01979 8,1583 0.0 979.5 125.6 3,079.9 565,8953 951.5 485 450 2250 0.01979 0.01916 18,111.4 0.0 2,174.5 278.7 3,358.7 584,285.5 1,005.0 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 180.5 3,539.2 596,197.2 1,037.9 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 168.5 3,707E 607,316.7 1,067.4 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 190.4 3,898.2 619,878.0 1,099.5 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 119.2 4,017.3 627,741.4 1,118.9 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,0173 634,515.6 1.106.9 350 350 350 0.01781 0.01797 (5,575.7; 0.0 (669.4; 0.0 4,0173 628,939.9 1,116.8 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,554.0 712,949.0 1,116.8 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 326.7 4,880.6 734,502.1 1,161.7 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 281.5 5,162.2 753,076.9 1,198.4 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 106.0 5,268.2 760,072.1 1,211E 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1423 5,41 0.5 769,457.8 1,229.4 <

l TOTAL BAT VOLUME = 7,317.0 GALLONS l l TOTAL RWSTVOLUME 23,373.1 GALLONS l 265XFB50 ABB Combustion Engineering Nuclear Services Page 110 of 167 i

_ _ _ _ ~ ~ _ _ _ . _ -. _ _ . __. _ -_ _ _ _ _ . _ _ _ _ . _ _ _ _ _ . _ _ _ . _ _ _ _ _ _

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-56 SEQUOYAH PLANT COOLDOWN FROM 54PF TO 200*F (XENON FREE)

BAT AT3.75 wt% BORIC ACID: RWST AT 2650 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TIN F PZR SPECIFIC VOLUMB SilRINKAOB BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PR ESS. MASS @ 70"F @ 70 7 ADDED B/A MASS CONC (cu.ft/lbm)

Ti(T) Tf(T) (pain) Vi Vf (Ibm) (gallons) (gallons) (1bm) (Ibm) (Ibm) (ppmboron) 547 547 2250 1.00000 1.00000 0.0 5,831 3 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 184.5 1,929.8 531,920.9 634.3 540 534 2250 0.02106 0.02090 3,907.4 469.1 0.0 152.2 2,082.0 535,980.5 679.1 534 500 2250 0.02090 0.02009 20,758.6 0.0 2,4923 319.5 2,401.5 557,058.6 753.7 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,924.8 557,581.9 917.1 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,312.6 1683 3,093.1 568,683.2 950.9 480 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 236.0 3,329.1 $84,255.9 996.2 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 180.5 3,509.7 596,167.6 1,0293 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 168.5 3,678.2 607,287.2 1,058.9 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 190.4 3,868.6 619,848.5 1,091.2 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 119.2 3,987.8 627,711.8 1,110.7 350 350 350 0.02698 0.01912 6,774.3 0.0 8133 0.0 3,987.8 634,486.1 1,098.8 350 350 350 0.01781 0.01797 (5,575.7] 0.0 (669.4; 0.0 3,987.8 628,910.4 1,108.6 ADD IN RHRS VOLUME (ASSUMB BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,520.5 712,915.5 1,108.6 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 326.7 4,847.2 734,468.6 1,153.8 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 281.5 5,128.7 753,043.4 1,190.7 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 106.0 5,234.7 760,038.7 1,204.2 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1423 5,377.0 769,424 3 1.221.8 l TOTAL BATVOLUME = 6,869.0 GALLONS l l TOTAL RWST VOLUME 23,6103 GALLONS l 265XFB50 ABB Combustion Engineering Nuclear Services Page 111 of 167

._ ._. ..._ __ _ , .- ._ . . - ~ ~ _ - ._ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, FEV.2 TABLE 2-57 SEQUOYAH PLANT COOLDOWN FROM 54PF TO 20(PF (XENON FREE)

BAT AT 3.875 wt% BORIC ACID: RWST AT 2650 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUM B SHRINKAOB B AT VO* . RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70 7 @ 707 ADDED B/A M ASS CONC i (cu.ftAbm)

Ti(T) Tf(7) (pain) Vi Vf Obm) (sallone) (sations) Obm) Obe) Obm) (ppe boron) 547 547 2250 1.00000 1.00000 0.0 5,634.0 0.0 0.0 1,7453 527,000.2 579.0 i 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 190.9 1,936.2 531,927 3 636.4 540 534 2250 0.02106 0.02090 3,907.4 469.1 0.0 157.5 2,093.7 535,992.2 682.9 534 500 2250 0.02090 0.02009 20,758.6 0.0 2,4923 319.5 2,413.2 557,0703 757.4 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,935.5 557,592.6 920.4 500 470 2250 0.02009 0.01951 16,141.2 0.0 1,938.0 248.4 3.183.9 573,982.2 969.8 470 460 2250 0.01951 0.01933 5,163.1 0.0 619.9 79.5 3,263.4 579,224.8 985.0 2 460 450 2250 0.01933 0.01916 4,965.4 0.0 596.2 76.4 3,339.8 584,266.6 999.4 i 450 400 2250 0.01916 0.01842 22,682.1 0.0 2,723.3 349.1 3,688.9 6M,297.8 1,062.0 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 190.4 3,879 3 619,859.2 1,094.2 370 350 2250 ' O.01804 0.01781 7,744.2 0.0 929.8 119.2 3,998.5 627.722.5 1,113.7

, 350 350 350 0.02698 0.01912 6,7743 0.0 813.3 0.0 3,998.5 634,496.8 IJ 01.8 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 3,998.5 628,921.1 1,111.5 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350l 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,532.6 712,927.6 1,111.5 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 326.7 4,8593 734,480.7 1,156.7 300 250 350 0.01743 0.01699 18,293.2 0.0 2,196.3 281.5 5,140.8 753,055.5 1,193.5 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 106.0 5,246.8 760,050.8 1,206.9 3 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1423 5,389.1 769,436.5 1,224.5 ;

I TOTAL BAT VOLUME - 6,671.8 GALLONS I l TOTAL RWSTVOLUME 23,6103 GALLONS l

i. 266XFB50 l ABB Combustion Engineering Nuclear Services Page 112 of 167 i

i i.

i BORIC ACID CONCENTRATION REDUCTION EFFORT l

l TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 l

! TABIE 2-58

SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200*F (XENON FREE)

BAT AT 4.00 wt% BORIC ACID; RWyr AT2650 ppm BORON: PZR @ 0% POWER LEVEL AVG.SYSlIEM P PZR SPECIRC VOLUME SIIRINKAGE BATVOL RWSTVOL IVA 'IUTAL TUrALSYS. FINAL PRESS. MASS @ 70'F @ 7U'F ADDED IVA MASS CONC.

(cu.It/lbm)

"D (*F) TT(*F) (psia) Vi Vf (ibm) (gnDons) (gaDons) (Ibm) (Ibm) (Ibm) (ppm boron]

547 547 2250 1.00000 1.00000 OD 5,4 51.0 0.0 0.0 1,7453 527,000 2 579D 547 536 2250 OD2125 OD2095 7,334.5 8804 0.0 3054 2,050 S 534,640 3 670.7 536 520 2250 0.02095 0.02055 10,148S 0.0 1,21 8.5 1562 2,2M.1 544,945.4 708.1 520 500 2250 0.02055 0.02009 11,918 3 0.0 1,431D 183.4 2,390.5 557p474 7503 RWyrHIED AND BLEED REQUIRED (GAlmNS) 6,000 500 500 2250 0.02009 OD2009 0.0 0.0 0.0 0.0 2,914 3 557,571 3 914D 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,31 2.6 1683 3,083D 568,673.1 947E 480 460 2250 0.01969 OD1933 10,3713 0.0 1,245.2 159.6 3,2424 579,204.0 778E 460 450 2250 0.01933 OD1916 4,965.4 O_0 596.2 76.4 3,319.1 \ 584,245 S 993.2 450 445 2250 0.01916 0.01908 2,3673 0.0 2842 36.4 3,355.5 \ 586,649 4 1,000D 445 420 2250 0.01908 OD1869 11,676D 0.0 1,401E 1793 3,535.2 ' 598,505.2 1,032.7 420 400 2250 0.01 8s9 0.01842 8,638S 0.0 1,037.2 133.0 3,668.1 6M,277.1 1,056.1 400 385 2250 0.01842 0.01822 6,4463 0.0 774.0 99.2 3,767.4 613,823.0 1 # 73.1 385 370 2250 0.01822 0.01804 5,924 2 0.0 711 3 91.2 3,858.5 619/08.4 1,088.4 370 360 2250 0.01804 OD1792 4,0154 0.0 482.1 61E 3,920 3 623,915E 1/Y)84 360 350 2250 0.01792 OD1781 3,728.5 0.0 447.7 57.4 3,9773 627,701E 1,107.9 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 3,977.7 634,476D 1p96.1 350 350 350 0.01781 OD1797 (5,575.7; 0.0 (669.4; 0.0 3,7773 628,9003 1,105E ADD IN RIIRS VOLUME (ASSUM E BORON CONC = RCS BORON CONC) 350 350 350 OD1797 OD1797 OD 0.0 0.0 0.0 4,509D 712,5104.1 1,1053 350 300 350 0.01797 0D1743 21,226.4 0.0 2,548.5 326.7 4,8353 734,457.2 1,151.1 300 250 350 0.01743 OD1699 18,293.2 0.0 2,1%3 281.5 5,1173 753/02.0 1,188.1 250 230 150 0.01699 OD1683 6,889.2 0.0 827.1 106.0 5,2233 760pz7.2 1,201.5 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 1423 5,3654 769,4119 I,21 9.2 l TOTAL BAT VOLUME = 6,331.6 GALLONS l l TOTAL RWST VOLUME = 23,767.5 GALLONS l 265XFB50 ABB Combustion EngineerinD NuclearServices Page 113 of 167 i

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-59 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200'F (XENON FREE)

B AT AT 3.50 =t% BORIC ACID: RWST AT 2700 ppm BORON: PZR @ 0% POWER LEVEL

~

AVO.SYS. TEM P PZR SPECIFIC VOLUM E SilRINKAO B BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (cu.ftAbm)

Ti(T) Tf (*F) (psia) Vi Vf (Ibm) (gallona) (ge] Ions) Obm) (Ibm) (1bm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 6,269.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 171.8 1,91 7.0 $31,908.2 630.1 540 532 2250 0.02106 0.02084 5,223.1 627.1 0.0 189.4 2,106.5 537,320.7 685.4 532 500 2250 0.02084 0.02009 19,442.9 0.0 2,334.4 305.0 2,411.5 557,068.5 756.8 RWSTFEED AND BLEED REQUIRED (OALLONS) 6,000 500 Soo 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,947.7 557,604.8 9243 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,312.6 171.5 3,119.2 568.709 3 958.9 480 450 2250 0.01969 0.01916 15,336.7 0.0 1,841.4 240.6 3,359.8 584,286.6 1,0053 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 184.0 3,543.8 596,201.7 1,039.2 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,31 4.8 171.8 3,71 5.6 607,324.5 1,069.6 400 370 2250 0.01842 0.01804 12.370.9 0.0 1,485.3 194.0 3,909.6 619,889.5 1,102.7 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 121.5 4,031.1 627,755.1 1,122.7 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,031.1 634,529.4 1,110.7 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4) 0.0 4,031.1 628,953.7 1,120.5 ADD IN RilRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,569.5 712,964.6 1,120.5 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,902.5 734,524.0 1,166.9 300 250 350 0.01743 0.01699 18,293.2 0.0 2,196.3 286.9 5,189.4 753,104.1 1,204.7 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5,297.5 760,101,4 1,21 8.5 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 145.0 5,442.5 769,489.8 1,236.6 l TOTAL BATVOLUME = 7,464.7 GALLONS l l TOTAL RWSTVOLUME 23,452.4 GALLONS l 27XFB500 ABB Combustion Engineering Nuclear Services Page 114 of 167

4 BORIC ACID CONCENTRATION REDUCTION EFFORT '

TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2

) TABLE 2-60 SEQUOYAH PLANT COOLDOWN FROM S47'F TO 200"F (XENON FREE)

B AT AT 3.625 wt% BORIC ACID: RWST AT 2700 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAOB BATVOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (ca.ftAbe)

Ti(T) Tf(T) (pals) VI Vf Obm) (smilons) (serione) Obm) Obe) Obe) (ppe boroe) l 547 547 2250 1.00000 1.00000 0.0 6,042.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 178.1 1,923.4 531,914.5 632.2 540 535 2250 0.02106 0.02092 3,252.0 390.4 0.0 1223 2,045.7 535,288.9 468.2 535 500 2250 0.02092 0.02009 21,413.9 0.0 2,571.0 335.9 2,381.6 557,038.7 747.5 RWSTFEED AND BLEED REQUIRED (GALLONS) 6,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,920.4 557,577.5 915.7 500 485 2250 0.02009 0.01979 8,1583 0.0 979.5 128.0 3,048.4 565,863.8 941.9 485 450 2250 0.01979 0.01916 18.111.4 0.0 2,174.5 284.1 3,332.5 584,259 3 997.2 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 184.0 3,51 6.5 596,174.4 1,031.2 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 171.8 3,6883 607,297.2 1,061.8 400 370 2250 0.01842 0.01804 12,370.9 0.0 1.4853 194.0 3,8823 619,862.1 1,095.0

370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 121.5 4,003.8 627,727.8 1,115.1 350 350 350 0.02698 0.01912 6,774 3 0.0 8133 0.0 4,003.8 634,502.1 1,103.2

, 350 350 350 0.01781 0.01797 (5,575.7) 0.0 (669.4; 0.0 4,003.8 628,926.4 1,113.0 i

ADD IN RHRS VOLUME (ASSUME BORON CONC. - RCS BORON CONC) 350 350 350 0.01797 0.01797 . 0.0 0.0 0.0 0.0 4,538.6 712,933.6 1J13.0

350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,871.5 734,493.0 1,159.6 i 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 286.9 5,158.4 753,073.2 1,197.6 ?

j 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5,266.5 760,070.4 1,211.4 230 200 '350 0.01683 0.01662 9,243.4 0.0 1,109.8 145.0 5,411.5 769,458.9 1,229.6 l l TOTAL BATVOLUME = 7,001.1 GALLONS l l TOTAL RWST VOLUME 23,689.0 GALLONS l I

27XFB500 ABB Combustion Engineering Nuclear SefVices Page 115 of 167

! t a

b'

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 c TABLE 2-61 SEQUOYAH PLANT COOLDOWN FROM 54PF TO 2007 (XENON FREE)

BAT AT 3.75 wt% BORIC ACID: RWST AT 2700 ppm BORON: PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAGE BAT VOL RWST VOL B/A TOTAL TOTALSYS. FINAL PRESS. MASS @ 707 @ 70 7 ADDED B/A MASS CONC (cu.ItJ1bm)

' (gallone) (gallone) (ppeboron)

Ti(T) Tf(T) (paia) VI Vf Obm) (Ibm) Obm) Obm) ,

547 547 2250 1.00000 1.00000 0.0 5,831 3 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 184.5 1,929.8 531,920.9 6343 540 536 2250 0.02106 0.02095 2,5983 312.0 0.0 101.2 2,031.0 534,620.5 664.2

^

536 500 2250 0.02095 0.02009 22,067.6 0.0 2,649.5 346.1 2,377.2 557,034.2 746.1 RWSTFEED AND BLEED REQUIRED (GALLONS) 6,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,91 6.4 557,573.4 914.5 500 480 2250 0.02009 0.01969 10,933.0 0.0 1,31 2.6 171.5 3,087.8 568,677.9 9493 480 450 2250 0.01969 0.01916 15.336.7 0.0 1,841.4 240.6 3,328.4 584,255.2 996.0 450 425 2250 0.01916 0.01877 11,731.1 0.0 1,408.5 184.0 3,51 2.4 596,170 3 1,030.1 425 400 2250 0.01877 0.01842 10,951.0 0.0 1,314.8 171.8 3,684.2 607.293.1 1,060.6 400 370 2250 0.01842 0.01804 12,370.9 0.0 1,4853 194.0 3,878.2 619,858.1 1,093.9 370 350 2250 0.01804 0.01781 7,744.2 0.0 929.8 1 21.5 3,999.7 627,723.7 1,114.0 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 3,999.7 634,498.0 1,102.1 350 350 350 0.01781 0.0179'l (5,575.7) 0.0 (669.4; 0.0 3.999.7 628,9223 1,111.9 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,533.9 712,929.0 1,111.9 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,866.9 734,488.4 1,158.5 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 ' 286.9 5,153.8 753,068.5 1,196.5 250 230 350 0.01699 0.01683 6.M9.2 0.0 827.1 108.1 5,261.9 760,065.8 1,210.4 230 200 350 0.01683 0.01662 9,243.4 0.0 1,109.8 145.0 5,406.9 769,454.2 .

1,228.5 l

l TOTAL BAT VOLUME - 6,711.8 GALLONS I l TOTAL RWST VOLUME 23,767.5 GALLONS l 27XFB500 ABB Combustion Engineering Nuclear Services Page 116 of 167 i

i

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . .. . . , _ _ - . . . ~ . . - . ._, . . . . - . . . . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . ___ _ _._ _ _ __

BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABLE 2-62 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200"F (XENON FREE)

BAT AT 3.875 wt% BORIC ACID: RWST AT 2700 ppm BORON PZR @ 0% POWER LEVEL AVO.SYS. TEM P PZR SPECIFIC VOLUME SHRINKAGE BAT VOL RWST VOL B/A TOTAL TOTAL SYS. FINAL PRESS. M ASS @ 70 7 @ 70 7 ADDED B/A MASS CONC (cu.ftAbm)

Ti(7) Tf(7) (pain) Vi Vf (Ibm) (gallons) (gallons) Obm) (Ibm) (1bm) (ppm boron) 547 547 2250 1.00000 1.00000 0.0 5,634.0 0.0 0.0 1,7453 527,000.2 579.0 547 540 2250 0.02125 0.02106 4,736.2 568.6 0.0 190.9 1,936.2 531,927 3 636.4 540 537 2250 0.02106 0.02098 1,946 3 233.7 0.0 78.5 2.014.7 533,9510 659.7 537 500 2250 0.02098 0.02009 22,719.7 0.0 2,727.8 356.4 2,371.0 557,028.1 744.2 RWSTFEED AND BLEED REQUIRED (GALLONS) 6,000 500 500 2250 0.02009 0.02009 0.0 0.0 0.0 0.0 2,910.7 $$7,567.8 9117 500 470 2250 0.02009 0.01951 16,141.2 0.0 1,938.0 253.2 3,163.9 573,962.2 963.8 470 460 2250 0.01951 0.01933 5,163.1 0.0 619.9 81.0 3,244.9 579,2063 979.5 460 450 2250 0.01933 0.01916 4,965.4 0.0 596.2 77.9 3,3218 584,249.6 994 3 450 400 2250 0.01916 0.01842 22,6811 0.0 2,7233 355.8 3,678.6 607,287.5 1,059.0 400 370 2250 0.01842 J.01804 12,370.9 0.0 1,4853 194.0 3,872.6 619,852.4 1,092.3 370 350 2250 0.01804 0.01781 7.744.2 0.0 929.8 121.5 3,994.1 627.718.1 1,112.4 350 350 350 0.02698 0.01912 6,7743 0.0 8133 0.0 3,994.1 634,4914 1,100.6 350 350 350 0.01781 0.01797 (3,575.7) 0.0 (669.4; 0.0 3,994.1 628,916.7 1,1103 ADD IN RHRS VOLUME (ASSUME BORON CONC = RCS BORON CONC) 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 4,527.6 712,9216 1,110.3 350 300 350 0.01797 0.01743 21,226.4 0.0 2,548.5 332.9 4,860.5 734,48 10 1,157.0 300 250 350 0.01743 0.01699 18,293.2 0.0 2,1963 286.9 5,147.5 753,062.2 1,195.1 250 230 350 0.01699 0.01683 6,889.2 0.0 827.1 108.1 5,255.5 760,059.5 1,208.9 230 200 350 0.01683 0.01602 9,243.4 0.0 1,109.8 145.0 5,400.5 769,447.9 1,227.1 l TOTAL BATVOLUME = 6,436.3 GALLONS l l TOTAL RWSTVOLUME 23,845.8 GALLONS l 27XFB500 ABB Combustion Engineering Nuclear Services Page 117 of 167

l BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 TABM 2-63 SEQUOYAH PLANT COOLDOWN FROM 547'F TO 200'F (XENON FREE)

BAT AT 4.00 wt% BORIC ACID: RWST AT 2700 ppm BORON: PZR @ 0% POWFJ1 LEVF1 AVG.SYS'IEM P PZR SPECII4C VOLUME SilRINKAGE BATVOL RW5TVOL B/A lulAL 'IUTAL SYS. HNAL PRESS. MASS @ 70'F @ 70'F ADDED IVA MASS CONC (cu.ftAbm)

"Il('F) 'IT(*F) (rmia) Vi Vf (Ibm) (ganons) (gaDons) (Ibm) (Itzn) (Ibm) (ppm boron) 547 547 2250 1D0000 1.00000 0.0 5,451D OD OD 1,7453 527,000 2 579D 547 538 2250 0.02123 0.02100 6,032.1 724 2 OD 251 3 1,9964 533,2834 6544 538 520 2250 OD2100 0.02055 11,451 3 OD 1,374 S 1794 2,176.2 544,914.5 698.2 520 500 2250 OD2055 OD2009 11,9182 0.0 1,431D 187D 2,363.2 557p20.2 741.7 RWSTFEED AND BGED REQUIRED (OAILONS) 6,000 500 500 2250 0 22009 0.02009 OD OD 0.0 0.0 2,903.5 557,5604 910.5 500 480 2250 022009 OD1969 10,933D 0.0 1,3126 171.5 3p75D 568,665.1 945A 480 460 2250 OD1969 OD1933 10,3713 OD 1,2452 162.7 3,237.7 579,199.1 9773 460 450 2250 0.01933 0.01916 4,965A OD 5962 77S 3,3154 584,242.4 992.2 450 445 2250 0.01916 0D1908 2,3673 OD 284.2 37.1 3,352.7 586,646B 999.2 445 420 2250 0.01908 OD1869 11/i?6D 0.0 1,401E 1811 3,5353 598,5053 1p323 420 400 2250 0.01869 021842 8,6383 OD 1p37.2 1353 3,671A 667,2803 1p57D 400 385 2250 0D1842 OD1822 6,446.7 0.0 774D 1 01.1 3,772.5 613,828.1 1p74.5 385 370 2250 0D1822 0D1804 5,924.2 OD 711 3 929 3,865A 619,845 3 10903 370 360 2250 0.01804 OD1792 4 154 0.0 482.1 63.0 3,928A 623,9233 1,1002 360 350 2250 0.01792 0D1781 3,7283 0.0 447.7 583 3,9863 627,710 3 1,110.5 350 350 350 0.02698 0.01912 6,7743 OD 8133 OD 3,9869 634,485.2 1p984 350 350 350 0 21781 OD1797 (5,575.7; OD (669A; OD 3,986.9 628,9093 1,1083 ADD IN RIIRS VOLUME (ASSUM E BORON CONC = RCS BORON CONC.)

350 350 350 0.01797 OD1797 OD OD OD On 4,51 9.4 712,9143 1,1083 350 300 350 0D1797 0.01743 21,226.4 OD 2,548.5 332S 4#52A 734,473 3 1,155.1 300 250 350 0D1743 OD1699 18,293.2 OD 2,1963 2863 5,1393 753,054D 1,193.2 250 230 350 021699 OD1683 6,889.2 OD 827.1 108.1 5,247A 760,051 3 1,207B 230 200 350 021683 0.01662 9,243.4 0.0 1,1093 145D 5,392.4 769,439.7 1,2253 l TOTAL BAT VOLUME = 6,175.2 GALLONS l l TOTAL RWST VOLUME = 23,923.9 GALLONS l 27XFB500 ABB Combustion Engineering NuclearServices Page 118 of 167

. . . . . _ . . . - ~ - . . - _ . - . - . ~ . . - - - . . . . ..

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, rov.2 TECHNICAL BA!E3 AND OPERATIONAL ANALYIE3 Table 2-64 Minimum Boration Volume vs.

Stored Boric Acid Concentration for Modes 1,2, and 3 Xenon-Free Scenario Minimum Volume faellons)

BAT BAT CONC. RWST RW8T RWST RW8T RW8T CONC. (wt.% CONC. CONC. CONC. CONC. CONC.

(ppa Boron) BORIC ACID) 2500 ppm 2550 ppm 2600 ppm 2650 ppm 2700 ppm 6120 3.50 8142.9 7993.6 7845.0 7623.5 7464.7 6340 3.625 7766.6 7692.2 7544.0 7317.0 7001.1 6560 3.75 7407.3 7185.8 7027.0 6869.0 6711.8 6775 3.875 7136.0 6988.5 6829.7 6671.8 6436.3 6990 4.0 6805.5 6646.7 6488.8 6331.6 6175.2 ABB Combustion Engineering Nuclear Services Page 119 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l

Table 2-65 Calculation of the 57,000 Gallon Volume in Bases Specification 3/4.1.2 38,250.0 gallons System Feed-and-Bleed (Part D) 11,966.3 gallons Cooldown to 350*F and 350 psia (Part A) 6,681.8 gallons Cooldown to 200*F on RHRS (Part C) 56,898.1 gallons Total 57,000.0 gallons Final Volume Rounded up to the nearest 1000 gallons l

l l

l ABB Combustion Engineering Nuclear Services Page 120 of 167 l

1 l

i BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS I l

Table 2-66 Calculation of the 26,000 Gallon Volume In Specification 3/4.1.2 2,381.9 gallons Cooldown to 400*F and 2250 psia (Part A) 13,500.0 gallons l Feed-and-BleedtoRaiseConcentration(PartB) 2,559.0 gallons Cooldown to 350*F and 350 psia (Part C) 6,681.8 gallons Cooldown to 200*F on RHRS (Part E) 25,122.7 gallons Total 26,000.0 gallons l Total,RoundeduptoNearest1,000 gallons i

i l

1 ABB Combustion Engineering Nuclear Services Page 121 of 167

l i

j

! BORIC ACID CONCIDITRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS i

i

!t i

FIGURE 2-1 SEQUOYAH UNITS 1&2 l.

SOLUBILITY OF BORIC ACID IN WATER 1e

,s _ . . . . . . .... . .... . . ..

O >

- 14 _ . . . . . .. . . ... . . ... . .. . . .

O U

- 12 -. - . . .-. . -. . . - ... .-

E O

oo -

p 10 _ . . . . . . ... . . .. . .. ..

S .

Z g _.... . . . _ . . .. .

O l- -

E s _ . .

g . ... .. . . . . . . . . . . . .

Z w -

U Z 4 ~"

O O

2 -- .- .. . . - --- . . ..

o i i i i i i i 20 40 60 80 100 120 140 160 180 TEMPERATURE ( F)

ABB Combustion Engineering Nuclear Services Page 122 of 167

l l

BORIC ACID CONCENT!#.ATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l

F IGURE 2-2 ;

1 SEQUOYAH UNITS 1 & 2 i REQUIRED BORON CONCENTRATION FOR PLANT COOLDODWN l 1,400 z 1,200 --

o 5 -

W ' , & , d 'r ' ^

w g ,2l ,

@1,000 --

g*' ' "

g, l g 800 --

e'- - - - --

P Gi l

z /

Z 600 -'

?i' O

O -

Z O

E 400 -' " * -

l 0

m .

1 o -

, - = = = \

w l E

l ggg _. .m os.a. . mor. 4. . . mos. s. . '

O W

E _ l 0 X ;

600 500 400 300 200 100 RCS TEMPERATURE -

F i COOLDOWN @ 10 F/ HR XENON FREE PEAK XENON INITIAL CONDITION X --G-I ABB Combustion Engineering Nuclear Services Page 123 of 167

l l BORIC ACID CONCENTRATI00t REDUCTICEI EFFORT CEM-502, REY.2 TECHNICAL BASES JutD OPERATICIERL AMELYSIS '

F I GURE 2- 3 ;

MODES 4 & 5 COOLDOWN - 350'F TO 135*F I NITI AL FEED- AND-BLEED w/ RWST @ 2500 ppm BORON 1,300 Z -

O : -

W 1,250 4 O

- +- :-~ 4 --. : + '

- :- +

+

m i

.. ,;. . < . . . .;. . .;. .;. .,(.

E . .

.;..r

. s X . 4. .

, . .s O- 1,200 ---v

. a

. s.

v- e- - --~

/- --

e. -/ : -

- v- '

/ : / :

o.

/ :/ :

I : - <

. . . . . ... . .. .. /:.. . /: : :

...,a.. ..f.

.s s

,'I Z :

. ./.

.c .

i O

1,150 - :- . - - :. . .. .:. .

. . l- :- .. .. .. ......:- .

. .: :/

s . .

f. .

<C .<......i. ..;. ."...,(.i. . . i.

E !/

t- -

Z . . .

-: //-/5' 1,100 +--- - .

e-LU : .c e. . .e. .e. .v..a-.

0 -

Z i 1

O . .. ..

. . j. .f.'. . . . .:.. .... . " . . . .. . . . ................!.... . l O

s' .

. o

FEED.i- AND-BLEED FOR.: 56 Ltl NUTES -

(f) 1,050 - . ~ ~l- .. - :. - . .:-.-. . ;.. - - . . :. .

O M .

RA'ISE

BORON CONCEt4TRATIDN :

E -

. FR.JM 1047 ppm, TO 1117 ppm -

~

'b " .

1' ' BE&DRE' 8TARTNG 'COOLDOWI BELOW ' 35Q'*F" ~ 4' I

1000 400 350 300 250 200 150 100 RCS TEMPERATURE -

F ACTUAL CONC. REQUIRED CONC.

O -+- '

ABB Combustion Engineering Nuclear Services Page 124 of 167

r l

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS )

i l

I 1

i FIGURE 2-4 ,

MODES 4 & 5 COOLDOWN - 350 F TO 135 F BLENDED MAKEUP -

BAT @ 3.5 wt% BORIC ACID

, 1,300 Z

O 1 ,250 - -

.- + .-.- -

CD _

jg;>ei>fix@!E#;g;>:-sed *5E E

1,200

/

,k-

/

Z .f O l 1,150 --

-.l- - . . . -

A E _

,I F /

Z :/C UJ 1,100 --

o -

-l'- - -

l Z # ,

O :/: l U

~

l

/

D l o 1,050 --

E l

1000 I I I I I 400 350 300 250 200 150 100 RCS TEMPERATURE -

F l REQUIRE 0 CONC. ACTUAL CONC.

C ..g....

1 ABB Combustion Engineering Nuclear Services Page 125 of 167 i

l l

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEM-602, REY.2 l TECHNICAL BASES AND OPERATIONAL ANALYSIS f

I l

F I GURE 2- 5 SEQUOYAH UNITS 1 & 2 RCS BORON CONC. vs TEMP. FOA 10 F/ hr COOLDOOOWN 1,400 l

r

~

l r

Z O 1,200 -- ----- -

E - -- er - -- ---

o ' ' '

CD

,,g 'AM,

~

-rt. -

1,000 -- - - -- d- -- Y - - - - -

o.

FEED-&- Bt.EED

( l

800 --

-U- -

.y- - - ---

je r Z /

l 0 -

t

- l i

H /

4 600 -- - - - - -

-l - -- - . - -

C A

H Z

/

i tu U :/ PEAK XENON SCENARIO i

Z A00 -- - - - - !- - --

/

t t

o o -

t BAT @ 3.5 wt% BOH C ACID U3 o 200 -- -

.? -- -

T l l

l l

0 ,

I l I !

600 500 400 300

200 100 I

r RCS TEMPERATURE -

F i

3 REQUIRED CONC. ACTUAL CONC.

i.

m. . . .y....

I I

l ABB Combustion Engineering Nuclear Services s Page 126 of 167 l

l l

l l i

4 l

r I

.1 l

noRIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 l TECENICAL BASES AND OPERATIONAL ANALYSIS l i

I I

F I GURE 2- 6 '

SEQUOYAH UNITS 1 & 2- 2 BORATION VOLUME vs CONCENTRATION IN BAT ,

9,000 . j

) ! i : i i : !

g ...

..>. ... ..:.. . ... i Z Q -

0 s .

i REG (ON OFi ACCEPTABLE

:OPERAT.

ION L: >

1 0,500 q Ty. ; . . :. . ...:.. . . . :. . . ~ . :. . . . . . :. . . - . 4 . . . . . . ~ .

1 J s

\:s 4 s. s

:. : : i, O

., s .

'; s

. . . . . . s. ,... :, : .

s' N :- . : : -

l es, ss. '.'.N.

s :s - -

s.. 4-I -

s. A . . .

B,000 -%.{ % -{. , -- } - -} - ' . - --} - -

.s

,s , ss:. i , .'sf.- .

. .--sss.

p_ ,

4 s s :

m -

'N.s M -..I- - - i -- -i - !-

'* s N-

'-i.-

%; '9, .

2 ; "N , }s i. ! : .

O E 7'500

.. + + . . . 6.. . N-

'sN h s . . ,M, sr. ?.'>,\...

U_

'- \.

Ys s

. s,s4 :,,s - .' j UJ -

t- - - --

.s X- S:- -

'< - - ?M. . --r-t y : 'S; : N :- -

%,,, h,'s.

D CONCENTRAT10N 1N RWST:

s; N 5s g

. : . N., ut, . .:,

O 7'000 : .2sou.som- .

. s. . : . N :. r, .,_'. .:.s . >,. . .

a :

?s 2550 ppm;

%,,N

. : N .,,',,'(, ,,

i 2600 ppm; M. ' s :. N

Z -

+- - - +- - -- - -- - .

' :%.,~.% - ~ :% N.

I O : 2550 ppmj l

,,% s 2700 ppm; y

N's,

}- : : : ;

6,500 . . . '

- .r-- . - - ~ ~ ~,--

9" E . . i l

l O 61i20 ppm

= - -

g . . . . . .

U$ ACCEPTABLE ' REGION 1 6,000 I I I I .I .I I I B,200 6,400 6,600 6,800 7,000 CONCENTRATION IN BAT -

ppm BORON ABB Combustion Engineering Nuclear Services Page 127 of 167 l

BORIC ACID CONCKNTkATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAI ANALYSIS F i GURE 2- 7 SEQUOYAH UNITS 1 & 2 BAT STORED VOLUME AEQUIAED vs BAT CONCENTAATION 9,500 m O :

Z O s REGION OF ACCEPT.hBLE OPERAtlON '

_t \ '

-J g,000 4p N; . :.

< s L9 N.s; NiN . .

. N .

@3. . i.'e s, . .h g . . . .;. . ..i. .

.i . .

I ii. N .

' .' .N

. s _.

Ns.,s; N.N N.s .N s.

B,500 s =- - :.

V.- r y' x -+ % '- % .-'

(

g s..N N :

., :N

- s *

\@s. ,' N.,g.......... Ny,, .

7 -.

. ...s... .. , , , . . , ..

- M sN:N N

s.,:

- g X.. .,,

N q: N LU ;

2 8,000 -

- Ac,.N:s v. N:i h y - ' N ;-: - ---

D N. N s'

'(: N.-.k, ::5s...'~

_j N. . ' ,:

O --

. . .. .. ' i ... a..

> X: s -s s.

. N.

.~.'Ns.

O CONCENTRAttON !!N RWSI: N s f 'i tu 7,500 - -

i- .i -- L - '.L h ' ' . . h'N-. . .

'y O- 2500 ppm.: * ;i. -

O 2550 ppm! '?s ,'v .s .

s h .

g - .. .;.

..2600. ppm 1.

. . . I' .s i.s.q.. ,5 2650 ppm! 'N i s 2 3

. 2700 ppm : :N D 7,000 -

+ . :. . . . + .

. +

2 *

+ .. ..:.. :s %

Z . REG I ON l')F .

~ '

5 ~

'EQD"$ir ' ~ 'lonXcts YAbi.E'66EnAYibk" "

[ . . . . . . . .

I I 6,500 I I I I I I 6,200 6,400 6,600 6,800 7,000 CONCENTRATION IN BAT -

ppm BORON ABB Combustion Engineering Nuclear Services Page 128 of 167 l

l

l 4

BORIC ACID CONCENTRATION REDUCTION EFFoar CEN-602, REY.2 TSCENICAL BASES AND OPERATIONAL ANALYSIS '

i I

t 4

FIGURE 2-B i SEQUOYAH UNITS 1 & 2 i RCS CONC.-vs TEMP., MAKEUP FROM RWST 0 2500 ppm .

1,400 t

_ XENON FREE CASE Z -

O 1,200 - - --- -- W ;

' :'N

-n- -

ct !

l h -

) j,'

,.ph j cootoown !

w/Mokeup from RWST

! E 1,000 .....-.~.)t$'~.

, p.

. . . - . , . - - . - ~ ~ - - - . - - --. ..

O {

p Q. A 5

~

h Feed-&- B l eed :

l from RWST 0 2500 ppm l B00 - - -

-rr - . - - - - - - - - - - - - - - -

y- -

i

/

Z xX O -

cm icown

- 7- w/Mskeup from BAT f H 600 4 z

- - - ~ ~ - - ~ ~ -

- - - - - - - -n- -

E '

d ;

l- ~

Z ,

UJ U ADO -- - - - - - -- ---

Z -------

O p..e_s_ei .a !

O -

from BAT 0 4.0 wtx ;

U3 o 200 -- . - - - - -- - - -- --- - - - - - --

E I l

O X I I I I 600 500 400 300 200 100 RCS TEMPERATURE -

F i

REQUIRED CONC. ACTUAL CONC, !

^ __v__

l ABB Combustion Engineering Nuclear Services Page 129 of 167

i i 4 !

i BORIC ACID CONCENTRATION REDUCTION RFFORT CEM-602, REY.2 j

TECHNICAL BASES AND OPERATIONAL ANALYSIS I

I 1

a 3.0 OPERATIONAL ANALYSIS l

i 1

3.1 INTRODUCTION

TO THE OPERATIONAL ANALYSIS l 1

l

!i The results of the evaluation performed to demonstrate the j general impact on plant operations of a reduction in the i

j boron concentration in the BATS are presented in this Section. The specific areas discussed include (1) operator response to emergency situations, (2) typical plant feed-and-bleed operations, (3) typical plant blended makeup

] operations, (4) plant shutdown to refueling, and (5) plant shutdown to cold shutdown. Since it obviously would be I

impossible to evaluate each of these five areas while i considering all possible combinations of plant conditions,

)

4 conservative initial plant parameters and analysis f l assumptions were selected for use in the analyses which q would lead to " worst case" results. As a consequence, the

results (i.e., the volumes and final concentrations that were obtained) will, in general, be bounding for any event j or any set of initial plant conditions. l J

3.2 RESPONSE TO EMERGENCY SITUATIONS Several operating evolutions which may have to be performed in response to a variety of emergency situations are discussed in this section. Accident boration requirements,

shutdown margin recovery, and emergency boration have been evaluated, and the findings are reported in the following paragraphs. This discussion includes an explanation of the !

manner in which the plant operating staff can continue to operate Sequoyah Units 1 & 2 safely with a reduction in the boron concentration of the solution stored in the BATS.

2 ABB Combustion Engineering Nuclear Services Page 130 of 167 l

i l l l

l l l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 l I

TECHNICAL aASES AND OPERATIONAL ANALYSIS l l

3.2.1 Accident Boration Recuirements l During the feasibility study, the plant Accident Analyses in Chapter 15 of the FSAR were reviewed. In the FSAR, no ;

mention is made of boric acid addition to the RCS from the BATS. During safety injection, the charging pumps are aligned to the RWST for reactivity control. Accordingly, the immediate consequences of such events as the steam line ;

break, overcooling, boron dilution, etc., will not be affected by the reduction in BAT concentration.

The Design Difference and Applicability Document, EPM-2, has also been reviewed. In this document, a concern was raised regarding a potential return to criticality during the cooldown following a Main Steam Line Break (MSLB) or a Steam Generator Tube Rupture (SGTR) event. Following a SGTR, the !

plant procedures and instructions (contained in E-3, Steam Generator Tube Rupture; ECA 3.1, SGTR with Loss of Reactor l

I Coolant - Subcooled Recovery Desired; and AOI-24, Steam .

Generator Tube Leak), plant operators are directed to borate the RCS to maintain shutdown margin. The boration is to be performed using either the RWST or a BAT. With the reduction in the BAT concentration, it will be necessary to

, revise the required BAT volumes as listed in those l

procedures. With a minimum concentration equal to 3.5 l

l weight percent in the BATS, the new required volumes will be l 3.5 times the volumes presently listed.

l During an MSLB, plant procedures and instructions also l

direct the operating personnel to borate the RCS to maintain I shutdown margin. With the reduction in BAT concentration, it will also be necessary to revise the requirements for l stored volume in the BATS, as in the case of the SGTR ABB Combustion Engineering Nuclear Services Page 131 of 167 I

BORIC ACID CONCENTRATION REDUC

ION EFFORT CEN-602, 3 LEV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l discussed above.

t 3.2.2 Shutdown Marcin Recovery In the event that the required shutdown margin is lost, the action statements associated with Technical Specifications 3.1.1.1, 3.1.1.2, 3.9.1, and 3.10.1 require that boration be initiated at a rate greater than or equal to 10 gpm using a L

solution with a boron concentration greater than or equal to 20,000 ppm or its equivalent. This requirement is discussed in detail in Section 2 of this report. The reduction in boric acid concentration in the BATS necessitates a revision to the action statements, increasing the flow rate requirement from 10 gpm to 35 gpm. Proposed modifications of the boric acid line to the blending tee will enente the I

availability of this delivery rate.

l 3.2.3 Emeraency Boration The main flow path for emergency boration runs from the boric acid transfer pumps directly to the charging pump suction, via emergency flow control valve, 1(2)-FCV-62-138. l These flow control valves and the flow path are designed for !

I a flow of 150 gpm, the output of 2 boric acid transfer i pumps.

1 The Sequoyah Emergency Boration Procedure, AOI-34, discusses the use of other flow paths for emergency boration. Boric acid solution can be charged through either the normal boration path (via 1(2)-FCV-62-140 and 1(2)-FCV-62-144), or l the alternate emergency boration path (via 1(2)-FCV-62-140 and 1(2)-VLV-62-929). In the existing configuration, 1-inch diameter piping has been used in these flow paths. TVA ABB Combustion Engineering Nuclear Services Page 132 of 167

l l

1 BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS intends that this piping be replaced with 2-inch diameter piping in order to increase the flow capacity through normal boration flow paths to the charging pump suction. Since the alternate emergency flow path is the third option, with limited usage, it is judged that this piping may remain as 1-inch diameter.

AOI-34 also provides information regarding the volume (s) of boric acid required for boration when emergency boration is required in response to a cooldown or in the event one or more RCCAs are not fully inserted. AOI-34 provides a listing of the required volumes of boric acid solution at a concentration of 20,000 ppm; volumes are provided as a function of RCS average temperature range and as a function of the number of RCCAs not fully inserted. At the new minimum concentration of solution in the BATS, 3.5 weight percent, it will be necessary to revise AOI-34 to increase the volumes of solution which must be maintained in the BATS by a factor of 3.5; i.e, the stored volume will be 3.5 times greater than the volumes currently listed in AOI-34.

3.3 FEED-AND-BLEED OPERATIONS During a feed-and-bleed operation performed to increase system boron concentration, the charging pumps are used to inject concentrated boric acid into the RCS, with the excess inventory normally being diverted to the liquid waste system via letdown. The rate of increase in boron concentration at l l

any given point in time is proportional to the difference !

between the system concentration and the concentration in i i

the charging fluid. The equation describing feed-and-bleed has been derived from this relationship; the equation and its derivation are presented in Appendix 1. It follows ABB Combustion Engineering Nuclear Services Page 133 of 167 l l

I

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS logically that, given a reduction in the boron concentration in the BATS to the point at which heat tracing is no longer i

required, the maximum rate of change of RCS boron l concentration that can be achieved during feed-and-bleed I will be less than is currently achievable.

The purpose of the evaluation described in this section was 1 to determine the rate of change in RCS boron concentration which may be achieved with a reduced concentration of boron in the BATS, using feed-and-bleed. The analysis was performed assuming hot zero power conditions, with other key parameters and conditions as shown in Table 3-1. Feed-and-bleed operation was analyzed with one and two charging pumps operating and from initial boron concentrations in the RCS of zero ppm and 1000 ppm.

The results are presented in Tables 3-2 through 3-5.

Equation 9.0 of Appendix 1 was used to generate the results in these tables. The value of the system mass used to obtain the time constant in Equation 9.0 was calculated as I

follows:

(m,) = (m,) + (m,)

or 10,812 fta 444.6 ft3 (m ) = # = 525,254.9 lb, 0.021251 ft /lb,m 3

0.02698 ft /lb)2) 3

Specific volume of compressed water 0 547'F and 2250 psia Specific volume of saturated water 9 2250 paia ABB Combustion Engineering Nuclear Services Page 134 of 167

i i

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 i TECENICAL BASES AND OPERATIONAL ANALYSIS From this system mass (525,254.9 lb.) , the value of the feed-and-bleed f

time constant with one charging pump delivering 75 gpm is ,

525,254.9 lb, 75 gpm x 8.329 lb,fgallon m '

or ;

I T,3 = 840.85 minutes l c j The value of the Feed-and-Bleed time constant with two charging pumps delivering 75 gpa each (total of 150 gpm) is 525,254.9 lb,, ,

- - 150 gpm x 8.329 lb) gal Or l T 33, = 420.423 minutes i

NOTE: Use of 2 charging pumps is limited to Modes 1, 2, and 3 by TS 3.1.4.2. .

The boron concentration required for the cases shown in Tables 3-2 through 3-5 are plotted in Figures 3-1 through 3-4 for comparison. Note that even with reduced boron concentrations, significant rates of increase in boron concentration in the RCS will still be achievable following the reduction in the concentration in the BATS.

Density of water 9 70 *F ABB Combustion Engineering Nuclear Services Page 135 of 167 i

l i BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS i I f 3.4 BLENDED MAKEUP OPERATIONS

1 1 l j During typical plant blending operations, concentrated boric l

I acid via 1(2)-FCV-62-140 is mixed with demineralized water l via 1(2)-FCV-62-142 at the blending tee and then added to the volume control tank (VCT). Since the ability to blend I

and add makeup to the RCS and to other systems is important to plant operations, two parametric studies were performed ,

3 to demonstrate the effect of a reduction in boron concentration in the BAT. The studies performed were as i follows: .

i j 1. Flow through 1(2)-FCV-62-140 was varied between 2.0 gpm and 40.0 gpm while the flow through 1(2)-FCV-62-143 is varied to give a total flow out of the blending tee of '

i 75 gpm, through Flow Control Valve 1(2)-FCV-62-144. '

2. Flow through 1(2)-FCV-62-140 is varied between 2.0 gpm and 40.0 gpm while the flow through 1(2)-FCV-62-143 is varied to give a total flow out of the blending tee of 150 gpm, through Flow Contrl Valve 1(2)-FCV-62-144.

In each of these studies, the temperature in both the BAT ;

and the demineralized water supply was assumed to be 70*F, and boric acid concentrations of 3.5, 3.625, 3.75, 3.875, and 4.0 weight percent were considered.

I The results are shown in Tables 3-6 and 3-7. The final ;

concentration out of the blending tee in each of these tables was obtained using the following equation:

, (Fy x Cy) (100) (1748.34)

(Fy x C y) + ( F,ye x D,)

i ABB Combustion Engineering Nuclear Services

~

Page 136 of 167 I

t

l BORIC ACID CONCENTRATION REDUCTION EFFORT TECHNICAL BASES AND OPERATIONAL ANALYSIS CEN-602, REV.2 In this equation, C , is the the blending tee in ppm boron, Fboron concentration leaving 7 is the flowrate coming out of 1(2)-FCV-62-140 in gallons per minute, Cy is the boron concentration in the BATS in Ib, per gallon F , is ,

the total flow leaving the blending tee in gpm D, is the density of water at 70*F in lb, per gallon , and 1748.34 is the conversion factor between concentration expressedn i weight percent boric acid and concentration expressed in terms of ppm boron. (See Appendix 4 this conversion factor.)

for a derivation of The data contained in Tables 3-6 and 3-7 are plotted in Figures 3-5 and 3-6.

Note that following the reduction in BAT concentration ,

a full range of flowrates blended makeup and boron operations. concentrations is available for 3.5 SHUTDOWN TO REFUELING - MODE 6 Shutdown to refueling conditions is normally th e most limiting evolution that an operator must perform involving system boration, i.e.,

of the maximum amount of boron A shutdown to the to RCS.this e refueling normally occurs at the end of each fuel cycle ,

when the boron concentration for criticality is low , and an increase accomplished.

to the refueling boron concentration must e b

In the most limiting case, boron concentration must be raised from zero ppm to the prescribed refueling concentration of 2500 ppm.

The results of the evaluation of plant shutdown t o refueling conditions are discussed in this Section. The evaluation was performed to demonstrate the effect of a reduction ni BAT concentration on makeup inventory requirements. A list of key parameters and conditions assumed in the analysi s is ABB Combustion Engineering Nuclear Services Page 137 of 167

l l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS contained in Table 3-8. The evaluation was performed for EOL conditions in order to maximize the amount of boron that must be added to the RCS. During this transient, it is necessary to increase the boron concentration in the RCS from zero ppm to the present refueling concentration of 2500 ppm. The shutdown for refueling was assumed to take place as follows-r

1. RCCs are inserted to bring the reactor to hot zero power conditions.

2. At time = 0 (following shutdown), feed-and-bleed is commenced, with one charging pump operating and taking suction from the BATS. (Two cases were run, the first l with the boron concentration in the BATS at 4.0 weight percent, the second with the concentration in the BATS i at 3.50 weight percent).

1 l

l 3. The feed-and-bleed operation is continued for 150 !

' i minutes for the first case (BATS at 4.0 weight percent) !

and for 220 minutes in the second (BATS at 3.50 weight percent).

i i

4. Plant cooldown and depressurization is commenced, taking the RCS from an average coolant temperature and system pressure of 547'F and 2250 psia, to a pressure of 350 psia and an average coolant temperature S 350*F.

5. The RHRS is aligned and placed in operation after the primary coolant is at 350 psia and the temperature has decreased below 350*F. (Prior to initiation,the boron concentration in the RHRS is assumed to be equal to the concentration in the RCS.)

ABB Combustion Engineering Nuclear Services Page 138 of 167 l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS

6. Following alignment of the RHRS, plant cooldown is continued from 350*F to 135'F at 350 psia. An 8-hour stram generator soak is required at a temperature between 310*F and 290*F.

7. Makeup inventory is supplied from the BATS.

The boric acid concentration as a function of temperature and the corresponding inventory required from the BATS as determined by the analysis are shown in Tables 3-9 and 3-10.

The coolant average temperature and boron concentration data from this table are plotted in Figures 3-7 and 3-8. The boric acid concentration during the initial feed-and-bleed operation was calculated for each case using the methodology discussed in Section 3.3 above. Concentration during the subsequent plant cooldown was calculated in the same manner as the concentration for the plant cooldown in Section 2.4.

Note that the boron content of the RCS was raised from zero ppm at the start of the evaluation to greater than 2000 ppm by the time the plant had been cooled and depressurized to ,

1 135'F and 350 psia. A total volume of 37,145.2 gallons of l 3.5 weight percent boric acid solution was required. Of this volume, 16,500 gallons were used during the initial 220 minute feed-and-bleed operation, and 20,645.2 gallons were l charged into the RCS to compensate for coolant shrinkage l during the cooldown. For the 4.0 weight percent case, a I total volume of 31,895.2 gallons was required. Of this I volume, 11,250 gallons were used during the 150 minute feed-and-bleed operation, and 20,645.2 gallons were charged to compensate for coolant contraction.

Each BAT contains a usable volume of 10,100 gallons.

As shown in Table 3-9, the volume of 4.0 weight percent ABB Combustion Engineering Nuclear Services Page 139 of 167

)

f BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS boric acid solution required to conduct the shutdown to :

refueling operation is approximately 2.56 times the capacity of one BAT. (With a boron concentration of 3.50 weight percent in the BATS, the volume required is 2.94 times the capacity of one BAT.) This result is conservative or bounding and thus represents the maximum volume that could be required, assuming a refueling concentration of 2000 ppa boron and the specified BAT concentration. The stored volume of boric acid solution required by Technical Specifications 3.1.2.5 and 3.1.2.6 should be contained in one BAT for each Unit. Since there are only three BATS with a combined capacity of approximately 30,300 gallons available for both Units (or, with two tanks, a maximum capacity of 20,200 gallons dedicated to a single Unit),

additional provisions or operator action may be required in order to establish a Mode 6 condition in the plant.

~

i These provisions could include some combination of the -

following:

1. The initial plant feed-and-bleed and some portion of the plant cooldown may be performed using the RWST, decreasing the total inventory needed from the BATS.

2. a. Prior to commencing the evolution, all three BATS are filled and are available for use.

I

b. During the initial phase of the cooldown, makeup may be taken from one BAT until depleted. The charging pumps may then be realigned to take suction from the second BAT for continued charging, and the first BAT may be replenished while cooldown is continued.

ABB Combustion Engineering Nuclear Services Page 140 of 167

l i i

n i

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS These provisions or operator actions would be necessary only once during each fuel cycle, just prior to the time a shutdown for refueling is to be performed. These are relatively simple actions which may be planned in advance so as to have no impact on maintenance activities or on the refueling schedule.

3.6 SHUTDOWN TO COLD SHUTDOWN - MODE 5 As discussed above, shutdown to refueling is the most limiting evolution that an operator must perform involving system boration. This evolution is normally performed only once during each fuel cycle, just prior to refueling.

Conditions such as unscheduled plant maintenance may occur during a fuel cycle, however, which require that the plant be taken to cold shutdown conditions. Although not limiting ;

with respect to boration requirements, it is important to have the ability to perform such a shutdown quickly and 1 efficiently. i l

The results of the evaluation of shutdown to cold shutdown are described in this section. The analysis was performed to determine the effect on makeup inventory requirements of a reduction in BAT concentration. A list of key parameters

( and conditions assumed in the analysis is contained in Table l 3-11. This shutdown-to-cold-shutdown evaluation was performed using a more realistic EOL cooldown endpoint of j 1030 ppm boron, rather than the peak xenon case described in Section 2 of this report. The steps followed in reaching l

cold shutdown are as follows:

1. RCCs are inserted to bring the reactor to hot zero power conditions.

1 l

ABB Cornbustion Engineering Nuclear Services Page 141 of 167

BORIC ACID CONCENTRATION REDUCTIoM EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS

2. A plant cooldown and depressurization is initiated to reduce system pressure from 2250 to 350 psia and average coolant temperature from 547'F to a temperature

$350*F. Makeup inventory is supplied from the BATS.

3. The RHRS is aligned and placed in operation at a pressure of 350 psia and a temperature $350'F.

4. After placing the RHRS in operation, plant cooldown is continued from 350*F to 200*F. Makeup inventory is supplied from the BATS.

The results of the evaluation showing the system boron concentration as a function of temperature and the total BAT inventory requirements are given in Tables 3-12 and 3-13.

In both cases, the concentration in the RHRS was assumed to be equal to the concentration of the RCS at the time of RHRS i initiation. System boron concentration as a function of l temperature is plotted in Figures 3-9 and 3-10. The !

concentration at each time step during the plant cooldown ,

was calculated using the methodology described in Section l 2.4 of this report. During the period in which blended '

makeup was used, data were calculated using the methodology described in Section 3.4.

I A total volume of 11,702.7 gallons of 4.0 weight percent boric acid solution (13,956 gallons of 3.50 weight percent) was required to complete the shutdown to cold shutdown with l the boric acid concentration in the RHRS equal to that in 1

the RCS at the time of system initiation. These results are conservative, as plant operating procedures require recirculation of the RHRS through the RWST prior to initiation of RHRS, and the concentration within that system ABB Cornbustion Engineering Nuclear Services Page 142 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS will normally be at or near that of the RWST any time that the RHRS is placed in operation.

3.7 LONG TERM COOLING AND CONTAINMENT SUMP pH The impact of the Boric Acid Reduction Effort on post-LOCA long term cooling and containment sump pH has been reviewed and evaluated. The results of each evaluation are discussed qualitatively below.

Typically, the performance of the Emergency Core Cooling System (ECCS) during extended periods of time following a loss-of-coolant accident (LOCA) is analyzed to address residual heat removal via continuous boiling of fluid in the i

reactor vessel. As borated water is delivered to the core region via safety injection while virtually pure water escapes as steam, high levels of boric acid may accumulate in the reactor vessel. As an input to this analysis, boron concentration in the BATS was assumed to be at the maximum concentration of 22,500 ppm (12.87 weight percent). Any such calculation will conservatively bound the maximum boric acid and tank concentration of 4.0 weight percent proposed as the result of the analysis described in this report.

Since the solution stored in the BATS is not pumped into the RCS by the Emergency Core Cooling System during the Design ,

Basis Accident, the change in BAT concentration proposed l herein will have no effect on the Containment Sump pH l Analysis, i 1

l I

i l

ABB Combustion Engineering Nuclear Services Page 143 of 167 ;

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS 1 l

l Table 3-1 f

Key Plant Parameters and Conditions Assumed in j Generating the Feed-and-Bleed Curves l

I i

1 3

RCS Volume 10-812 ft RCS Pressure 2250 psia RCS Average 547*F Temperature Pressuriser Volume 444.6 ft Pressuriser Temp. Saturation

& Press.

RCS Leakage Zero BAT Temperature 70*F Mixing Between RCS Complete and and PZR g Instantaneous PZR Level During Constant Feed and Bleed Letdown Flowrates 1 - Charging Pump 75 gpm 2 - Charging Pumps 150 gpa ABB Combustion Engineering Nuclear Services Page 144 of 167

. . . . _ _ _ . - . . . . ~ -. . . __ ~ . -_ ..

BORIC ACID CONCENTRATION REDUCTIf,N CFFORT CEN-602, R';v. 2 TECHNICAL BASE 3 AND CPERATIONAI, ANALY"E3 TABLE 3-2 SEQUOYAH UNITS 1 & 2 - FEED & BLEED EVALUATION FEED & BLEED @ 75 GPM: INITIAL CONCENTRATION @ O ppm BORON TIME 1. EXP. VALUE RWST BAT BAT BAT BAT BAT M**tal 1. e * @ 2500 ppm @ 3.5 wt% @ 3.625 wt% @ 3.75 wt% @ 3.875 wt% @ 4.00 wt%

o.oooo o_oooo o.oooo 0oooo ooooo ooooo o oood o.oooo 1o 0000 o.otta 29.sss7 72.3429 74.928s 77.s t o2 no_o23s n2 877s 20.ocoo o.o23s sa.7s2o 143.83o4 148.9872 1s4.1040 1s9.2408 184.3778 30.o00o I o.o3so I n7 e23o 214.472n ???132s 229 7923 237.4s21 24s.1 tin 4o.oooo E o o4ss I t i e.i429 2n 4.2no t 294.433o 3o4.sssa 314.73n7 324_nsis so coco I oes77 E 144.32ss as3 2n21 3as.n7sa 37s.49st 391 t iin 4o3.72s, eo.oooo I o.oens I 172.17so 421.42n s 43s.479s 4si.saan 4sssnta 4as.s32s 7o.oooo 0.o799 199 s952 4ss7991 so8.24s9 s 23.7o28 s41.1 s94 ssas182 so.oooo I o.o9en I nen9ai sss 3s34 s7stn74 s9s o21s e14 asss e34 ss9s 90.0000 l o.i oi s l 2s3.7s3 4 smi.130s e 43.3139 nes.4971 en7.eno4 7o9.ssa s 500.0000 l o.iiri l 290.3191 898.13o3 71o s349 73s 139s 7s9.8442 7s4.1489 330.0000 l o.i n s l 30s sson 7so.a si s 777_i so t no3.9ss7 nao.7s74 ss7 ssso

$200000 l o.133o I 332.49n nis.naas n42assa a71.9843 901 o299 93o.o9s2 130.000o I o.1432 I ass.1172 a7s ss4s 9o7 s803 939 insa 97o.4714 toot 77e9 340.0000 l o_is34 l an3.439, 93ns347 972os3s t oos.s729 so39.o92o ior,siti Iso oooo o.1834 4o8.4817 999.7219 to3s.4BB4 lo71.1949 11o8.9o14 1142 so79 1s0.0000 l o1733 433.1 Bas 1oso 3ost 1o99.1731 1138.o411 1173.9092 1211.7772 17o.oooo o1833 4s7 s229 112o.1128 11 so.1187 120o.12o7 124o 1247 122o.1297 iso.oooo I o.1927 I 4st.7sss 1179.2132 1221.3279 1283.4427 130s.ss7s 1347.s722 iso.oooo I o.2023 I soserss 1237.siso 12st.niss 132s oisi 137o.21 s s 1414.4172 200.000o o.2117 s29.2088 129s.3284 1341 sBai 1387.B 497 1434.1114 14so3730 210.000o E o_nto I ss2. sos 9 13s93sss 14oo.es39 144m9s23 1497>so7 i s4s.s492 no oooo I o no2 I s7s s29s 14an.7io4 14s9.omi c - 1 so9.332s i ss9.s437 i son.9 s47 no.oooo I o.uss I s9s.2mia 14a4.3991 ists. esso isen999o i s21.299o i s73.sss9 240.0000 l o.24s3 I n;o.7a41 is19.4293 is73 s947 in27.9soo tan?22s3 573n 4907 2sooooo E o2s72 I e42.9so9 is73noso is3o oiss 1sas??4o 1742 4314 179n nans ABB Combustion Engineering Nuclear Services Page 145 of 167

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-6C2, R2v.2 TECHNICAL BA C3 AND CPERATIONAL ANALY O3 TABLE 3-3 SEQUOYAH UNITS 1 & 2 - FEED & BLEED EVALUATION FEED & BLEED @ 150 GPM: INITIAL CONCENTRATION @ Oppm BORON TIME 1 - EXP. VALUE RWST BAT BAT BAT BAT BAT (minutes) E 1.e W 2500 PPM 3.5 wt% 3.625 wt% 3.75 wt% 3.875 wt% @ 4.00 wt%

ooooo l o. coco o ocoo o.0000 0.000o ooooo o.oooo o_ coco io_oooo l oo23s nn7822 i42nait 14n9879 is4 io47 is9 ,418 384 27s4 20.0000 l o o4s5 its.1434 es4.2si4 294.4343 3o4.5s72 3i4.74oi 3 24.n931 30.o000 l o.oss9 172.175s 421 43o5 43 s.4st a 451.5327 4ss.Es3a 4si.s24s 40.0000 o0909 228.8911 555_3559 575.190o 595 o242 8149583 834 8924 m oooo I o _112 i sno2202 Sn8is24 71oEsat 73s 1499 7E9_8478 vs4_1s24 so.oooo I o.133o 332.4927 B13.s3 89 R42.9025 371.98a1 901.0337 g30_ogg 3 7ooooo 0.1534 383.44o8 9395388 972 oSB1 10o5.5773 1039.o988 to72 s159 go.000o o.1733 433.19o4 loso.3o98 t o98.1778 1138.o4so 1173 9142 1211.7924 90oooo I o.1937 4si77o8 1i799sa, 1221.3ss, i,8s44ai isos s8an 3 3 47_87mo_.

ioo.oooo I o.2117 529.2o99 1295.3319 1341.5937 1387.9558 1434.1174 14so.3793 iio cooo I o.23o2 575.5322 14os 7183 1459 o27s 15o9.33s9 1559.eSo2 i sos.9s14 iro oooo l o 24s3 82o.7ess 1519.4358 1573.7o11 1 s27.9 ss7 1sas ,323 373s.497s isooooo I o raso 884 9379 1827 E554 98sE8793 17432082 1 Ro1 9311 198o oM99 14o_oooo I o2832 708o709 1732.128o 1795 o255 1558.9229 1913a202 19so 717s i so.oooo I o 3ooi 75o.19oo in38 ,,,i 19ainoi4 1987.3non som, 98o2 mass s295 1sooooo I o.3 i s5 791.3192 193a.s929 2008.os78 2o75.2424 2144.417i 2213.59i9 17ooooo o_3328 231 4A18 203E1975 21o7 RR11 stanERA7 ,$M1 ,M43 ,1,M 94oo iso.cooo I o34s3 n7o.vooo 2i31.1914 22o7.3o54 ,,n3.4193 2259_s333 2435 s473 190.000o o.3s3s 90s 99ss 2224 929o 23o4.3907 2383.9525 24s3.2142 2542.77so 200.000o l o.3788 94s 3929 2318.4s33 2399 1941 2481.9249 2584 8553 2847.3988 2io ocoo I o ,92, 9n,Dios sansassi 249, 7891 env7 893, ,882 mism ,749 s2 4 22o.oooo I o.4o74 tols.5s94 2493.1279 25n218a2 287s _2ons 27so.24aa 2n49 rani 23o.0000 l o.4214 1053.39o3 2578.3592 287o.4425 278, E,87 2a54.8109 2948.8951 24o.oooo I o.435o t os7.392s 2ssi.Es52 275s.e41s 2 51.s9s4 294a.755o 3o41.ni t 7 ABB Combustion Engineering Nuclear Services Page 146 of 167

BORIC ACID CONCENTRATION REDUCTION GFFORT CEN-602, rov.2 TECHNICAL BACCO AND CPERATIONAL ANALYS"33 TABLE 3-4 SEQUOYAH UNITS 1 & 2 - FEED & BLEED EVALUATION FEED & BLEED @ 75 GPM; INITIAL CONCENTRATION @ 1000 ppm BORON TIME 1 - EXP. VALUE EXP.VALUE RWST BAT BAT BAT BAT BAT (minutes) 1-e* e* @ 2300 PPM @ 3.5 wt% @ 3.625 wt% @ 3.75 wt% @ 3.875 wt% @ 4.0 wt%

0.00000 0.0000 1.0000 1000.0000 1000.0000 1000.0000 1000.0000 1000.0000 1000.0000 10.0000 0.0118 0.9882 1017.7334 1060.5205 1083.1042 1085.8879 1088.2718 1070.8552 20.0000 0.0235 0.9785 1035.2572 1120.3258 1125.4824 1130.5992 1135.7380 1140.8728 30.0000 0.0350 0.9850 1052.5738 1179.4238 1187.0834 1194.7431 1202.4028 1210.0828 40.0000 0.0485 0.9535 1089.8857 1237.8230 1247.9758 1258.1287 1288.2815 1278.4344 50.0000 0.0577 0.9423 1088.5953 1295.5319 1308.1484 1320.7849 1333.3814 1345.9979 80.0000 0.0889 0.9311 1103.3050 1352.5588 1387.8098 1382.8808 1397.7118 1412.7828 70.0000 0.0799 0.9201 1119.8171 1408.9111 1428.3878 1443.8248 1481.2813 1478.7381 80.0000 0.0908 0.9092 1138.1340 1484.5973 1484.4314 1504.2854 1524.0995 1543.9335__

90.0000 0.1015 0.8985 1152.2581 1519.8253 1541.8085 1583.9917 1588.1750 1808.3592 100.0000 0.1121 0.8879 1188.1914 1574.0027 1598.5073 1823.0120 1847.5188 1872.0213 110.0000 0.1228 0.8774 1183.9385 1827.7372 1854.5358 1881.3344 1708.1330 1734.9317 120.0000 0.1330 0.8870 1199.4954 1880.8384 1709.9019 1738_9874 1788.0328 1797.0983 130.0000 0.1432 0.8508 1214.8703 1733.3079 1784.8134 1795.9190 1827.2245 1858.5300 140.0000 0.1534 0.8488 1230.0835 1785.1591 1818.8782 1852 1973 1885.7184 1919.2355 150.0000 0.1834 0.8388 1245.0770 1938.3972 1972.1037 1907.8102 1943.5167 1979.2232 180.0000 0.1733 0.8287 1259.9131 1887.0297 1924.8977 1982.7857 2000.8338 2038.5018 170.0000 0.1830 0.8170 1274.5738 1937.0835 1977.0875 2017.0715 2057.0755 2097.0798 180.0000 0.1927 0.8073 1289.0811 1988.5058 2028.8205 2070.7353 2112.8501 2154.9848 190.0000 0.2073 0.7977 1303.3772 2035.3838 2079.5841 2123.7848 2187.9852 2212.1857 200.0000 0.2117 0.7883 1317.5240 2083.8437 2129.9054 2178.1871 2222 4287 2288.8904 210.0000 0.2210 0.7790 1331.5038 2131.3531 2179.8515 2227.9500 2278.2484 2324.5488 220.0000 0.2302 0.7898 1345.3179 2178.4985 2228.8098 2279.1207 2329.4318 2379.7428 230.0000 0.2393 0.7807 1358.9888 2225.0885 2277.3885 2329.8864 2381.9864 2434.2884 240.0000 0.2483 0.7517 1372.4584 2271.1237 2325.3890 2379.8544 2433.9197 2488.1850 ABB Combustion Engineering Nuclear Services Page 147 of 167

_ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ - . _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ . - - _ _ _ _ - _ - - _ __ _ _--__ - _-___m.____ - - _ _ _ _ _ _ _ _ . _ . _ - _ . . .___.___-________.____m._..__:

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-002, rov.2 TECHNICAL BAS ~.3 AND CPERATIONAL ANALYC3 TABLE 3-5 SEQUOYAH UNITS 1 & 2 - FEED & BLEED EVALUATION FEED & BLEED @ 150 GPM; INITIAL CONCENTRATION @ 1000 ppm BORON TIME 1 - EXP. VALUE EXP.VALUE RWST BAT BAT BAT BAT BAT (minutes) 1-e"" e ** @ 2500 pom @ 3.5 wt% @ 3.625 wt% @ 3.75 wt% @ 3.875 wt% @ 4.0 wt%

00000 O_0000 1 0000 1000_0000 1000 0000 1000.0000 1000 0000 1000 0000 1000_0000 10_0000 O0735 0978E 103M 7M74 11703787 1125 4830 1130 E9gs 113E 7388 1140 g735 700000 0 048E O9535 1089 8980 1237_B241 1947 9770 12MR1799 178A 2R7R 177s_4357 30 0000 0.0899 09311 110130EE 13M2 M807 1387 8113 13R7 8874 1397_7134 1417 7845 40 0000 O0902 09092 1138_1347 1484_ E994 1494.4338 1KO4 7877 1574 1019 1543 9380 500000 O_1171 ORA 79 ties 1922 1 E74_OOM 7 1E99E100 18730147 1847 5195 1877 0743 80.0000 0.1330 0.9870 1199 4982 18E0R394 1709 9050 17329708 178R0387 1797_101 g 70 0000 O_1E34 09488 1730 0845 17AE182E 1919 8M1R 1RE7 ?O10 inRE 7707 1919 7395 30 0000 O_1733 OM787 1259 9147 1997 033E 1974 9017 1987 7899 2000 83M1 703RMO83 90 0000 O 1927 O9073 17R9 t3873 1998 5100 ?O7R 8749 7070 7399 2117 RM4a 7154 98g7 100 0000 0 7117 07893 1317 M7E3 70R28423 7179 9107 7178 1770 ???? 4339 198n 8957 110 0000 0.7302 0.7899 134E 3193 217RE034 ???RA147 7779 1780 73794373 7379 7488 1200000 O_2483 0.7517 1372 4800 7271_1299 73?M 19 45 7379 8800 7433 9258 7499_1912 130 0000 0.7880 07340 1399 9877 7381.5773 7419.7047 2477 23'O 7M359579 7594Og43 140_0000 07R32 0.7189 1424 R47M 7449 2997 7M117971 IE73 8948 783M M970 7897_4Rg 4 150_0000 O3001 08999 1450.1140 7 M3 8.1481 7801 7754 7887 3042 7737AR47 7799 483E 180 0000 0.3185 08R35 1474_791 E 287038E7 78R9 M400 27ER_7147 7a77 an95 7A97 0847 170_0000 O3378 0.8874 149RRRR9 7707804R 777M790M 7947 9781 7970 8817 29913473 1 RO 0000 O34R3 08517 1M77 4700 27R79114 7ME9 0?E4 7935 1394 3011 7K13 3097_3873 190_0000 0.3838 08384 154M 3979 1R81.3304 7940.7971 3070 9M39 3099.7158 3179_1774 700 0000 037R8 08214 1E87 R359 2937.9081 3070 8389 31011873 31n8 09n8 378A n?94 210_0000 0 3937 O BORR 1E99 7487 2017 BR19 309R 8050 31B4 M7R1 3770 4517 3358 3742

??O0000 O_4074 OE978 1811.1417 309E7007 3174.7404 3783 7207 32M7 R710 3441_s813 230_0000 0.4214 OE798 1837 0142 3157 0071 3749 OR83 3341.1705 3433 7542 SM7M 1390 240_0000 0.4350 0.5850 1852.43E7 32'8 8281 3321.8947 3418.7413 3511.7979 3 808_R545 ABB Combustion Engineering Nuclear Services Page 148 of 167

BORIC ACID CONCENTRATION REDUCTION CFFORT CEN-602, R0v.2 TECHNICAL BASE 3 AND CPERATIONAL ANALY rc TABLE 3-6 SEQUOYAH UNITS 1 & 2 - TYPICAL BLENDED MAKEUP OPERATIONS

@ 75 GPM OUT OF BLENDING TEE CONCENTRATION OUT OF TEE (ppm BORON)

FLOW (GPM) THROUGH l BAT BAT BAT BAT BAT 1(2)-FCV-62-140 1(2)-FCV-62-143 l @ 3.5 wt/% @ 3.625 wt/% @ 3.75 wt/% @ 3.875 wt/% @ 4.0 wtI%

2 73 l 168.9 175.2 181.5 187.7 194.0 4 71 ! 337.5 350.0 362.5 375.1 387.7 6 69 l 505.8 524.5 543.2 562.0 580.8 8 67 ! 673.8 698.6 723.6 748.6 773.6 to 65 l 841.4 872.4 903.5 934.7 965.9 12 63 l 1008.7 1045.9 1083.1 1120.4 1157.8 14 61 ! 1175.7 1219.0 1262.4 1305.8 1349.3 16 59 1342.4 1391.7 1441.2 1490.7 1540.4 18 57 l 1508.7 1564.1 1619.7 1675.3 1731.0 20 55 l 1674.8 1736.2 1797.8 1859.5 1921.2 22 53 l 1840.5 1907.9 1975.5 2043.2 2111.0 24 51 l 2005.9 2079.3 2152.9 2226.6 2300.4 26 49 2171.0 2250.4 2330.0 2409.6 2489.4 28 47 l 2335.7 2421.1 2506.6 2592.2 2678.0 30 45 l 2500.2 2591.4 2682.9 2774.4 2866.1 32 43 l 2664.3 2761.5 2858.8 2956.3 3053.9 34 41 l 2828.2 2931.2 3034.4 3137.7 3241.2 35 39 l 2991.7 3100.5 3209.6 3318.8 3428.1 38 37 l 3154.9 3269.6 3384.5 3499.5 3614.6 40 35 l 3317.8 3438.3 3559.0 3679.8 3800.7 ABB Combustion Engineering Nuclear Services Page 149 Of 167

- - - _ - - - - - - - _ _ _ _ - - _ _ _ _ - - - _ - - - - - - - - - - - - - - - _ - - - - - - _ - - - - _ _ _ - - - - - - - _ _ ---_--_--_____------------_---__------_-----------_--a

BORIC ACID CONCENTRATION REDUCTION CFFORT CEN-602, rov.2 TECHNICAL BA"TJ2 AND OPERATIONAL ANALY".".*33 TABLE 3-7 SEQUOYAH UNITS 1 & 2 - TYPICAL BLENDED MAKEUP OPERATIONS

@ 150 GPM OUT OF BLENDING TEE l CONCENTRATION OUT OF TEE fPPM BORONI FLOW (GPM) THROUGH ! BAT BAT BAT BAT BAT 1(2)-FCV.62-140 1(2)-FCV-62-143 l @ 3.5 wt/% @ 3.625 wt/% @ 3.75 wt1% @ 3.875 wt/% O 4.0 wit %

2 148 l 84.5 87.6 90.8 93.9 97.1 4 146 168.9 175.2 181.5 187.7 194.0 6 144 253.3 262.6 272.0 281.5 290.9 8 142 337.5 350.0 362.5 375.1 387.7 10 140 421.7 437.3 452.9 468.6 484.3 12 138 505.8 524.5 543.2 562.0 580.8 14 136 589.8 611.6 633.5 655.3 677.3 16 134 673.8 698.6 723.6 748.6 773.6 18 132 l 757.6 785.6 813.6 841.7 869.8 20 130 841.4 872.4 903.5 934.7 965.9 22 128 925.1 959.2 993.4 1027.6 1061.9 24 126 1008.7 1045.9 1083.1 1120.4 1157.8 26 124 1092.3 1132.5 1172.8 1213.2 1253.6 28 122 1175.7 1219.0 1282.4 1305.8 1349.3 30 120 l 1259.1 1305.4 1351.8 1398.3 1444.9 32 118 1342.4 1391.7 1441.2 1490.7 1540.4 34 116 1425.6 1478.0 1530.5 1583.1 1835.8 35 114 1508.7 1564.1 1819.7 1875.3 1731.0 38 112 1591.8 1850.2 1708.8 1767.4 1826.2 40 110 1874.8 1736.2 1797.3 1859.5 1921.2 ABB Combustion Engineering Nuclear Services Page 150 of 167

I BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Table 3 - 8 Key Plant Parameters and Conditions Assumed in l

the Shutdown-to-Refueling Evaluation l l

RC8 Volume 10,812 ft Initial RCS Average 547'F i Loop Temperature B Pressurizer Volume 444.6 ft Pressurizer Pressure Saturation RCS Leakage Zero l BAT Temperature 70'F Mixing Between RCS Complete and and Pressuriser E Instantaneous Pressurizer Level Constant During Feed & Bleed i Initial RCS Concentration 0 ppa Boron BAT Concentration 3.5 E 4.0 wt.% Borio Acid RW8T Concentration 2500 ppm Doron RHR8 volume l 1500 ft 3

Boron Concentration in RERB=

Boron Concentration in RCS at Time of RRR8 Initiation i Refueling Concentration 2500 ppa boron (Mode 6) B l l

l ABB Combustion Engineering Nuclear Services Page 151 of 167

BORIC ACID CONCENTRATION REDUCTION CFFORT CEN-602, rov.2 TECHNICAL BA;O3 AND OPERATIONAL ANALY C3 TABLE 3-9 SEQUOYAH REFUELING COOLDOWN FROM 547*F to 135 F FEED & BLEED AND MAKEUP FROM BAT WITH 3.5 wt% BORIC ACID @ 70 F AVo.sV8. TEMP. PZR SPECinC VOLUME SHRINKAGE BAT VOL RWST VOL B/A TOTAL TOTAL FINAL PRESS. MASS @ 70'F @ 70*F ADDED BORIC ACfD SYS. MASS CONC.

7,(*F) T, (*F1 frelet V, lft'Ab.) V, fft 8Ah,) Pb,1 Igenenel fgallonel Ob,1 t!b.) Ob,1 ppm bema Md7 Md7 97%n n n119M n n919M nn 1 A MM n nn nn d 9 AR A M74 M91 M 1 ann 7 Md7 Min ??MM nn917M nn?n74 119n17 1 MMd K nn inq 9 A A7K n M41 919 d 1 Min M Man Mon ??Mn n n7n79 on7nn9 in 1?n M ?17MM nn AM7 9 M 111 n MM4 49n 1 1 ArtM n Ron d7n SSMn n n9mm n ot AM1 1 A 141 9 1 gin n nn Knm a K q1n A M7 A 71 A 7 174d 9 476 dan 99En nn1491 O M19M id Ani n 17a A 4 fi f* M14 m A AMn 9 MOS 134 M 1 enA n dan din 79En n M14M nninMM 11 n119 i AM A i nn Kn1 n A 9M4 9 An A A M 7 _1 7 fin A 1 din aan 99mn n ninMM n nin7m n M1M R 1 n3d 2 nn 317 4 7 771 A A1M 27A.4 7 OAM 4 Man man 97Mn n ninta n n174 7 11 ann 7 1 d77 A nn dit 9 7 7n? m A97 Ain 1 91dM M man MMn 7 9 ed) nn1747 nn17m1 177a K dd7 7 00 11M S 7 nin n A11 M AS n 91 Aq n MMn MMn n rai n n17nt nniq7 #M M7K vi rA Aq di nn nn 7 nin n ASM an A 1 7 ing 1 AMS SMn MAT nn?A9n nn1919 A 774 M Ali 3 nn nn 7 Ran n Al?7AnA 71 AM 7 MMn MMn MMn n n1797 n n17mv nn nn nn nn 7minn AM 7 7 An A 91 AM 7 ADD IN RHRS VOttfME tASSUME 00RON CONC. = RCS BORON CONC _t 3Mn _1Mn mMn n n1747 n n17n7 nn nn nn nn a anM n 717 San n 91 AM 7 1Mn MM iMn n 61747 nn17d1 91 97 A A 9 Man M nn 7 A4 e e AMA n 71q 97R 1 7 Sai 1 2nn 9En MMn n n1743 o01R99 in 9417 ? 19 A 3 oo A A1 M in 313 3 7Mn Sam n 9 myg 9 9Mn San MMn n n1 Aqq nn1A91 1 ASA 1 dit A f1 n 17d 1 in ad? 7 7A17mt 7 9 tem A 7dn 97n MMA n 01 A91 nn1A7A A M1 A 9 7A7 A f1 fi 71 A 1 in A79 O 7An Min a 9199 A

?9o 9m MMn nn1A7A nn1AA7 A inn n 7d9 4 on 991 A in ani M 771 QMn n 9 AMo q 2nn inn 3Mn n nt M A, ootMan M ndo 1 voi 9 on 911 n is 11M s 7n1 nn,7 9 dan 7 inn 1An imo n n1Rdn nM1Rin M nid M An7 n nn int 4 11 747 1 7mA inn A 9 M19 7 ,

iAn 1Mn 2Mn n n1 A,a n nt R1, 9 Mn ? A and n nn at n 11 ano n 7an n9, n 9 Mu 9 iMn idn MMn n n1 A12 n ni Atn , nnd 7 SMn a nn 7M A 11 A AA A 7,n on,1 , Mu ,

1dn 13M 3Mn nn1A7n nn187R 11831 139 R nn 47 7 11 MnB R 7971RR 4 7 E39 E FEED & BLEED VOLUME FROM BAT (0 ppm TO 1408.7 ppm, 220 MINUTES @ 75 GPM) = 16,500.0 GALLONS TOTAL VOLUME FROM BAT = 37,145.2 GALLONS ABB Combustion Engineering Nuclear Services Page 152 of 167

802IC ACID CONCENTRATION REDUCTION CFFORT CEN-602, rov.2 TECHNICAL BA;E3 AND CPCRATIONAL ANALYCE3 TABLE 3-10 SEQUOYAH REFUELING COOLDOWN FROM 547*F to 135*F FEED & BLEED AND MAKEUP FROM BAT WITH 4.0 wt% BORIC ACID @ 70*F AVG *SYS* TEMP

PZR SPECIFIC VOLUME SHRINKAGE SAT VOL RWST VOL B/A TOTAL TOTAL FINAL PRESS. MASS O 70*F O 70'F ADDED BORfC ACID SYS. MASS CONC.

T,(*F) T,(*F trele) V, fff/1b) V,it?Ab) Db) 19eBonel 19atene) 9*) Db) Db) ppm becen 547 547 2250 0.02125 0.02125 0.0 11.250 0 0.0 0.0 3.455.3 528.710.3 1.142.8 I 547 530 2250 0.02125 0.02079 11.281.7 1.354.5 0.0 470.1 3 925.4 540.482.0 1.289.8 530 500 2250 0.02079 0.02009 18.120.5 2.175.8 O_0 730.5 4 855.9 669.312.9 1.455_4 500 470 2250 0.02009 0.01951 18.141.2 1.938.0 0.0 872.5 5.328 4 578.128.7 1.817.0 470 440 2250 0.01951 0.01900 14.883.0 1.788.9 0.0 820.1 5 948.5 591.829_8 1.767.9 440 410 2250 0.01900 0.01855 13.811.9 1.858.3 0.0 575.5 8 524.0 808.017.2 1.882.2 410 390 2250 O_01855 0.01828 8.813.8 1.0 34.2 O_O 358.9 8 882.9 814.989.7 1.958.7 l 390 360 2250 0.01828 0.01792 11.888.7 1.427.4 0.0 495.4 7.378.3 827.373.8 2.058.2 380 350 2250 0.01792 0.01781 3 728.5 447.7 0.0 155.4 7.533.8 831.257.7 2.088.5 350 350 350 0.01781 0.01797 r5.575.71 t089.41 0.0 0.0 7.533 8 825.882.0 2.105.1 1 852 350 SAT O.02898 0.01912 8.774.3 813.3 0.0 0.0 7.533.2 832.458.2 2.082.8 350 350 350 0.01797 0.01797 0.0 0.0 0.0 0.0 7.533.8 832.458.2 2.082.8 l

ADD IN RHRS VOLUMF lASSUME BORON CONC. = RCS BORON C04C.1 350 350 350 0.01797 0 01797 0.0 0.0 0.0 0.0 8_798.5 738.471.8 2.082.8 350 300 360 0.01797 0.01743 21.228 4 2.548.5 0.0 BC3.7 98522 780.553.9 2_218.8 300 250 350 0.01743 0.01899 18_293.2 2 198.3 00 737.4 10.389.8 779.584.8 2.330.0 250 240 350 0 01899 0.01891 3 428.3 411.8 0.0 138_2 10 527.3 783_151.1 2.350.3 240 220 350 0.01891 0.01878 8.518.3 782.4 0.0 282 7 10.790.5 789.930.1 2.388.2 220 200 350 0.01878 0.01882 8.188.0 742.9 0.0 249.5 11.039.9 798.387.8 2.423.7 200 180 350 0 01882 0.01849 5.840.1 701.2 0.0 235.4 11.275.4 802_443.1 2.458.8 180 180 350 0.01849 0.01838 5.014.0 802.0 0.0 202.1 11.477.5 807.859.2 2.4 84.5 100 150 350 0.01638 0.01833 2.632.4 304.0 O_0 102.1 11.579.8 810.293.7 2.498.5 150 140 350 0.01833 0.01828 2.084.7 250.3 0.0 94.0 11.883.8 812.482.4 2.509.9 140 135 350 0.01828 0.01828 1.163.1 139.8 0.0 48.9 11.710.5 813.872.4 2 518.2 FEED &BAT BLEED FROM BAT (0 ppm to 1,142.6 ppm) _= 31,895.2 11250.0 GALLONS GALLONS (150 MINUTES @ 75 GPM)

TOTAL VOLUME ,

ABB Combustion Engineering Nuclear Services Page 153 of 167

l 1

l i

' j 1

BORIC ACID CONCENTRATION REDUCTION EFPORT CEN-602, REV.2 !

TECHNICAL BASES AND OPERATIONAL ANALYSIS l

Table 3-11 I Key Plant Parameters and Conditions Assumed in l

1 the Shutdown-to-Cold-Shutdown Evaluation I

RCS Volume 10,812 ft 3 l

l 1

Initial RCS Average Temperature 547'F 3

Pressurizer Volume 444.6 ft Pressurizer Condition Saturation l RCS Leakage Zero BAT Temperature 70*F Domineralized Water Temp. 70'F Mixing Between RCS complete and and Pressurizar Instantaneous Pressurizer Level Constant During Cooldown l Initial RCS Boron 0 ppa Boron Concentration BAT Concentration 3.50 E 4.0 wt% Borio Aoid I

RWST Concentration 2500 ppm Boron RHRS Volume 1500 ft Boron Concentration in RHRS Equal to Concentration in RCS at time of RERS Initiation l (Cases I and II)

ABB Combustion Engineering Nuclear Services Page 154 of 167

I BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, rov.2 TECHNICAL BA003 AND OP;RATIONAI, ANALYSE 2 l

l TABLE 3-12 SEQUOYAH PLANT COOLDOWN FROM 547 F to 200 F WITH BLENDED MAKEUP BAT @ 3.5 wt% BORIC ACID j A VO.8Y8. TEMP. PZR. SPECIFIC VOLUME SHRINKAGE BLEND BAT VOL PRIMARY H,0 VOL 8/A TOTAL TOTAL FMAL PAES S. MASS RATIO @ 70*F @ 70*F ADDED BORIC ACfD SYST.M A S S ComtC.

T,t*F) T,(*F) fretel V, tft'Ab) V, tft*/'b) (fb) (geNonel Igatone) Ob) Ob) Ob) ppe i boma 547 547 2250 0.02125 0.02125 0.0 0.00 0.0 0.0 0.0 0.0 525.254.9 0.0 547 530 2250 0.02125 0.02079 11.257.7 0.00 1.351.6 O_O 408.3 408.3 536.921.0 133.0 530 500 2250 0.02079 0.02009 18.120.5 0.00 2.175.6 0.0 657.2 1.065.5 555.698.7 335.2 500 470 2250 0.02009 0.01951 16.141.2 0.00 1.938.0 0.0 585.4 1.651.0 572.425.3 504.3 470 440 2250 0.01951 0.01900 14.883.0 0.00 1.786.9 0.0 539.8 2.190.8 587.848.1 651.6 440 410 2250 0.01900 0.01855 13.811.9 0.00 1.658.3 0.0 501.0 2 691.7 602.160.9 781.5 410 390 2250 0.01855 0.01828 8.613.6 0.00 1.034.2 0.0 312.4 3.004.1 611.087.0 859.5 390 360 2250 0.01828 0.01792 11.888.7 0.00 1.427.4 0.0 431.2 3.435.3 623.406.9 963.4 360 350 2250 0.01792 0.01781 3.728.5 0.00 447.7 O_O 135.2 1.570.6 627.270.7 995.2 350 350 350 0.01781 0.01797 (5.575.71 0.00 0.0 0.0 0.0 3.570.6 621.695.0 1.004.1 652 432 350 0.02698 0.01912 6.774.3 0.00 813.3 0.0 0.0 3.570.6 628.469.2 993.3 350 350 350 0.01797 0.01797 0.0 0.00 0.0 0.0 0.0 3.570.6 628.469.2 993.3 ADO IN SOCS VOLUME (ASSUME BORON CONC. = RCS BORON CONC.)

350 350 350 0.01797 0.01797 0.0 0.00 0.0 0.0 0.0 4.072.1 712.487.2 999.3 350 320 350 0.01797 0.01764 13.015.2 2.70 422.3 1.140.3 127.6 4.199.7 712.594.7 1.030.4 320 290 350 0.01764 0.01734 11.877.5 4.00 285.2 1.140.8 96.2 4.295.9 724.558.4 1.0 34.2 290 200 350 0.01734 0.01707 11.230.8 5.00 224.7 1.123.7 87.9 4.353.7 735 957.1 1.0 34.4 200 240 350 0.01707 0.01691 6.824.5 5.00 136.6 682.9 41.3 4.395.0 742.722.9 1.0 34.6 240 220 350 0.01691 0.01676 6.516.3 5.00 130.4 652.0 39.4 4.4 34.4 749.278.6 1.C 34.7 220 200 350 0 01676 0 01662 6.1P8 0 5 00 123 8 619.1 37.4 4.471.8 755,504 0 1,0 34.8 TOTAL BAT VOLUME = 13,956.0 GALLONS TOTAL PRIMARY H 2 O VOLUME = 5.358.7 GALLONS ABB Combustion Engineering Nuclear Services Page 155 of 167

. -- - -. . . . . .-- . ~ - . . - _ - - . . . - . - - - - ~ - - . ~ ~ - - - . .. .. . . . . . . . . ~. .-..

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, ROV.2 TECHNICAL BASO3 AND CPERATIONAL ANALYC2O TABLE 3-13 SEQUOYAH PLANT COOLDOWN FROM 547'F to 200*F WITH BLENDED MAKEUP BAT @ 4.00 wt% BORIC ACID t

AVO.SYS. TEMP. I'ZR. SPECIFIC VOLT 1ME SHRINKAGE BLEND BAT YOL PRIMARY H,0 VOL BlA TOTAL TOTAL F1 MAL PRESS. MASS RATIO 9 70 F @ 70 F ADOED 80RIC ACfD SYS. MASS CONC.

Y, t*r1 7, s*n (p.a.) V, m'ab) V, m'abJ ph) tessoas) temil sh) m) ab) p,,a b 547 547 2250 0.02125 0.02125 0.0 0.00 0.0 0.0 0.0 0.0 526 264.s 0.0 647 530 2250 0.02125 0.0207s 11.281.7 0.00 1.354.5 O_0 470.1 470.1 537.006.7 153.0 E30 500 2250 0.02079 0.02000 18_120.5 0.00 2.175.8 0.0 755.0 1 S SE.1 SES.nas t 33.3 600 470 2250 0.02000 0.01951 18.141.2 0.00 1.938.0 0.0 8725 1.a07.8 572_835.8 579.3 470 440 2250 0.01951 0.01900 14.883.0 0.00 1.788.3 0.0 820.1 2.517.a 588.199.0 748.4 440 410 2250 0.01000 0.01865 13.811.9 0.00 1.858.3 0.0 575.5 3.003.2 802.588.4 897.5 410 390 2250 0.01855 0.01528 E.813.8 0.00 1.034.2 0.0 358.3 3.452.1 811.558.3 988.3 390 380 2250 0.01828 0.01792 11.888.7 3.00 358.8 1_070.5 192 a 3.578.0 m23 E71.5 1.002.8 380 350 2250 0.01792 0.01781 3.728 5 3.00 111.9 335.7 38.B 3.814_8 827_23e a 1.007.4 360 360 360 0.01781 0.01797 f5.575.71 3.00 0.0 0.0 0.0 3.814.8 821_783.1 1.018.E 852 432 360 0.02898 0.01912 8.774.3 3.00 203.3 810.0 70.8 3.8E.4 82a.nos.O 1.025.0 350 350 360 0.01787 0.01797 0.0 3.00 0.0 ' O.0 0.0 m ans.4 sta an8.0 1.025.0 ADO IN RHRS VOLUME tA88UnsE BORON CONC. = RCS SORON CONC.)

360 360 350 0.01797 0.01797 0.0 3.00 0.0 0.0 0.0 4.177.7 712.872.7 1.026 0 350 320 360 0.01744 0.01725 7.775.8 3.00 211 4 700.2 70.5 4.248.2 720_413.0 1.031.0 4 320 290 350 0.01725 0.01707 7.528.2 4.00 180.7 722 m 54.8 4 sn2 e 727 tes.e 1_nis 1 290 280 360 0.01707 0.01891 8.824.5 E 00 138.8 882.s 41.3 4.344.0 734.am.8 1.033.5 280 240' 350 0.01891 0 01878 8.518.3 E.00 130.4 852.0 3e 4 4 ses 4 741.421.3 1.033.8 4

240 220 350 0.01891 0.01878 8.518.3 E.00 130.4 852.0 39.4 4_422.R 747.977.1 1.033.8 220 200 350 0.01878 0.01862 8.185.0 5.00 123.8 819.1 37.4 4.480.2 764.202.5 1.033.9 t

TOTAL BAT VOLUME = 11,431.0 GALLONS TOTAL PRIMARY H,0 VOLUME = 5,426.1 GALLONS ABB Combustion Engineering Nuclear ServlCes Page 156 of 167

! i l

1 l

l l

I BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 ;

TECHNICAL BASES AND OPERATIONAL ANALYSIS j F I GURE 3- 1 l SEQUOYAH UNITS 1 & 2 -

i FEED & BLEED, HOT ZERO POWER, O ppm INIT, 75 GPM '

2,000 i

l Z .-

O

. .. ' l<

1 l

O - .: '

LD 1,500 -.. .... .. . .. .. . . ,4..'f...............

E a .. ,A'

'.s G ~*/

.l/X g

... y:

, . ts'

}[ >

O 1,000 - - . . . . - . . ..

. El c:, ,

k ,. f .

T ../ !

F- -

.i*f l Z .r 1

u3 '

O .0.' . ,

Z :l 500 -.

- ,. A

m .$,.

o E

.,.?

5 '

)

OL I I I I I O 50 100 150 200 250 300 TIME -

MINUTES BAT @ 3.5 wt% BAT @ 3.75 wt% BAT @ 4.0 wt%

^

_M_ . . . ; ;. , . . .

i ABB Combustion Engineering Nuclear Services Page 157 of 167 l

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECENICAL BAsRS AND OPERATIONAL ANALYSIS

\

i F 1 GURE 3- 2 ,

SEQUOYAH UNITS 1 & 2 i FEED & BLEED, HOT ZERO POWER, O ppm INIT, 150GPM i 3,500 !

.s :

3,000 -- - - - -- -\' - -- I Z

.* ,A<

l O '

1 -

. ,/ ,

O .3 /- r CD . e' ;

2,500 --- - -- - - - - -

..g- - -- - l E <

...! b

.s, .

l 2,000

. . .g .,< . . .. . . .. .. . .. .

Z -

O :

Y' .

<C a 1,500 ... . ...

.Y

. . .g;f. . .. .. . .. .. . . .. . . .

I- .y ;

Z .,

W -

.. l O ,Q.o; -

Z // l O 1,000 U

- :l

.fI -- -- -- -- - - . -

Li) -

U .</

C 500 --

d- - - - -- - - - - - ..

.1

- J I I OL I I I O 50 100 150 200 250 300 TIME -

MINUTES BAT @ 3.5 wt% BAT 9 3.75 wt% BAT @ 4.0 wt% '

^

-M ,

a.

ABB Combustion Engineering Nuclear Services Page 158 of 167 i i

r

l l

.j BORIC ACID CONCENTRATION REDUCTION RFFORT CEN-602, REY.2 j TscuNrcar,nasas aND opsmaTroMar anar.rsrs 3 l

)

i I

F I GURE 3- 3

~

SEQUOYAH UNITS 1 & 2 l F & B, HOT ZERO POWER, 1000 ppm INIT, 75 GPM 3,000 [

l Z

O !

"9 2,500 -- -- - -- - - - - - -- - -

-f- ------

l 0] l

. ...,J' s ,

E _

Q I ,X',s. ;

S :::*X l 2,000 --. ... ....~ .... . .

...~,.t ,

.x ' . .. . .. . .. .. . .....

~

Z a ,Y:. ,#

O _

. ...q'

...,,a 4 :.r.,$

E 1,500 - - - - - -- - ..' .

I . , - i Z y !

W

.> l O , !

Z i O l U

1,000 !l - - ~ ~ ,- - - - - - - - - -- - - - - ---~ ~ -

O E

500 I I I I i O 50 100 150 200 250 300 TIME -

. MINUTES BAT 0 3.5 wt% BAT @ 3.75 wt% . BAT 0 4.0 wt%

ABB Combustion Engineering Nuclear Services Page 159 of 167

I I

i l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECENICAL BASES AND OPERATIONAL ANALYSIS i

I i

J F IGURE 3-4 i SEQUOYAH UNITS 1 & 2 F & B, HOT ZERO POWER, 1000 ppm iN1T, 150 GPM i

3,500 l i

Z .-- '

O 3 000 ~' ~~^ * *" ' ' ' " * ' " * * *";'":"" '

E ,- -

A l O .-

' ,)<'/,

1 LD -

.<../

E ..

O.

g 2,500 - ~ ~ ~ .~ . ,J'/

. - ~ ~ . (,3 . ,. . f. . . . - . ~ . .... .

e .

- .. x#

. , , /,

,. g ,

~~ '

Z / \

O 2,000 - ~ - - - ----s\lpf- -----.-- - - ~ ~ ~ . - - - ~

, . ,/~ ,

I- ./ -

4 .

T

~

. ,'l, V.

s- -*

./ .

Z .</

1.U 1,500 O

af -- -

./

1 Z .?'

l O . l 0 - ,

i in U 1,000 Rt - - -- -- - . - - . - --.. . . --

E 500 I I I O 50 100 150 200 TIME. -

MINUTES BAT 0 3.5 wt% BAT @ 3.75 wt% BAT @ 4.0 wt%

o ~ r.--. . . . :.t . .

ABB Combustion Engineering Nuclear Services Page 160 of 167

. - . - -. . .~ . .. - . .. . . . - - . - - - _ _ - - - - - - - _ - - - - _ _ _ _ _

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, m .2 TscsNICAL ansas AND OPERATIONAL ANALYSIS F IGURE 3-5 SEQUOYAH UNITS 1 & 2 BLENDED MAKEUP OPERATIONS w/ 75 GPM OUT OF TEE 3,500 Z

O E

O w 3,DDD ~ ~ - - - -- -- ~~- ~ ~~ - ~ - ~ ~ ~ ' ~ ~ ' "

E -

G ~

a . ',y-2,500 */

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

- - ~ ~ - -Q. .- /

-/ ' -'~'-

.*Y

. */ t

/

.w W 2,000 - - - - .. -- -- -- - - -

,...? , / l

---<g---...--.......

I- -

/

.. p LL -

.;*. /

O D I- 1,500 -' -. ~ ~ -

' . f.'

-- J- - . . ~ ... .....

> ./

O _ ,

I z ../

O .,/

- 1,DOO -.. ... . . . .

7,:, ..

I-

< 9 Cr . . ,d

p. .v z cy' w 500 - . . .- . . . . . . .

O f .. . .. ... . . ...

z .;' i O -

i O

I 0 I I I I I i i

O 5 10 15 20 25 30 35 l FLOW FROM 1(23-FCV 140 2

GPM !

BAT @ 3.5 wt% BAT @ 3.75 wt% BAT 0 4.0 wtx 0 9:- . s .. i l

1 i

l- ABB Combustion Engineering Nuclear Services Page.161 of 167 i ;

i e

i BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l

i TABLE 3-6 SEOLOYAH UNITS 1 & 2 BLENDEO MAKEUP OPERATIONS w/ 150 GPM OUT OF TEE 2,500 l

Z O -

E O

m E 2,000 -- .

Q. .'

O. ..-

, .~. g

. i i

/

X

./

W 1,500 --

. ~.' .[. . . .

w .> .

?/

p U- -

.. '/

. /

O *

./

.~/

k- .; /

D ,' /

g 1,000 -.-

, y. .

./

Z '

O

. .. ,'/, /

H /

& *.W. -

./

H 500 --

d' .

Z . .i LU .;7 O .;'

^~'

Z ~

O U

"b I I I 0 I O 10 20 30 40 50 FLOW FROM 1(2)- FCV 140 -

GPM BAT 0 3.5 wt% BAT 0 3.75 wt% BAT 0 4.0 wt%

0 - M --- .u..

ABB Combustion Engineering Nuclear Services Page 162 of 167

1 l

1 BORIC ACID CONCENTRATION REDUCTION EFFORT CEM-602, REY.2 TECENICAL BASES AND OPERATIONAL ANALYSIS- .

F I GURE 3- 7 .

j SEQUOYAH UNITS 1 & 2 REFUELING COOLDOWN FROM 547*F TO 135'F :

3,000 l -

I l z ,

l O 2 500 ~~ ~ ~ * * * * * ** * * ** **' *

l T l O I C _

E !

Q- :

O_ 2,000 - - - - -- - - --

l I _

r >

! z ;

O 1,500 -- - - - -.- -- . - --

~

<C _

! E p ,

l Z .

l 11J 1,000 -- - - - - - -- . - -- - - - --

[

O BAT @ 3.5 wt%

z l O _

l o

in U 500 -~ - - -- - -- - -. . -- - - -

E i 1

I ' ' '

0 o 6'00 500 400 300- 200 100 RCS AVEAAGE TEMPERATURE -

F l

l ABB Combustion Engineering Nuclear Services Page 163 of 167 i

t I

BORIC ACID CONCENTRATION REDUCTION RFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS F I GURE 3- 8 SEQUOYAH UNITS 1 & 2 REFUELING COOLDOWN FROM 547*F TO 135*F 3,000 f2,500 -- - * -

E O

m -

E S2,000 -- - - - - -

1 _

Z ,

O 1,500 -- - - - - - ""

l F-

<C 1 E '

F-- O Z

L13 1,000 -- "'

g47 g7 0~"M%' " l Z l O i 0 -

(D 500 -- - - - - - - -

I I I I O v 600 500 400 300 200 10C RCS AVERAGE TEMPERATURE -

F ABB Combustion Engineering Nuclear Services Page 164 of 167

sonic ACID CONCENTRATION REDUCTIOOf RFFORT CEN-602, REY.2 ,

TECHNICAL BASES AND OPERATIOIULL ANALYSIS I i

l FIGURE 3-9 l SEQUOYAH UNITS 1 & 2 SHUTDOWN TO COLD SHUTDOWN -

547 F TO 200 F 1,200 O 0000 2 1,000 -- - - * - - " * * - * * " * " " " - " " " " - * " " * - " "

O u_

O -

EO E

Q. 800 _. .. .. . ... . .......... .. . .. . . . ....

Q.

l l

, 1 -

i Z

O 600 -- -" - - - - " - - - "-- ---" - -- --

i k

<C

E -

l F l Z l g 400 _ . . .. . .. .. ... .

Z BAT @ 3.5 wt%

O o .

m

, O h

C 200 -- ... . ~ . . . - . .- . ...

i

! i o y I I I 600 500 400 300 200 100 RCS AVERAGE COOLANT TEMPERATURE -

F l '

l i ABB Combustion Engineering Nuclear Services Page 165 of 167

-- .-- .a - . , , - , , . , _ _ , , . . . , .,s.n.-- , n .. ,

i BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS FIGURE 3-10 '

SEQUOYAH UN I T S 1 & 2 SHUTDOWN TO COLD SHUTDOWN 1,000 I

z e O O 0000 O

g 1.000 --

O C -

E O.

O. 800 --

l t -

l 7

O 600 -

I l-BAT @ 4.0 wt%

e i b 400 --

c,

! 9 c

O -

U 07 o 200 -

E >

I I I I 0 y 600 500 400 300 000 100 ACS AVEAAGE TEMPEAATUAE -

"F l

ABB Combustion Engineering Nuclear Services Page 166 of 167

- - . . = _.- _ _ _ - _ - _ -

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS <

r

4.0 REFERENCES

l i

4.1 U.S. Nuclear Regulatory Commission Standard Review Plan i

NUREG-0800 Section 5.4.7. " Residual Heat Removal (RHR) i System" and Branch Technical Position-(RSB) 5-1 " Design :

Requirements of the Residual Heat Removal System" 4.2 Technical Data Sheet IC-11, US Borax & Chemical Corpo- i ration, 3-83-J.W. I I

1 l 4.3 TVA Correspondence, J. F. Lemons and T. R. Moffett, TVA ;

Nuclear Fuel, to W. E. Higgins, ABB Combustion l Engineering, February 2, 1993.

1 4.4 BACR Computer Code, Calculation 0000-MPS-1 CALC-013 l Rev. 00, Version 00 4.5 " Flow of Fluids", Technical Paper No. 410, Crane Co.,

1988 l

t i

i l

l ABB Combustion Engineering Nuclear Services Page 167 of 167

+----=v-?-- ---v- , ,.c-,,-.1m-_...,.y_,%- - - . . - - - , , - e,-c~w+, *e- e , , . .mm. .

I k

aoate AcIn concsuTRATIon RapocTrow Erroar CEN-602, REY.2 TscamicAL BASES AND OPERATIONAL ANALYSIS I

F Appendix 1 '

l Derivation of the Reactor Coolant System !

Feed-and-Bleed Equation' '

i Purnose of Definitions- I i

This appendix presents the detailed derivation of an !

i equation which can be used to compute the reactor calant system (RCS) boron concentration change-during a feed-and- '

bleed operation. For this derivation, the following .

definitions were used: I m =

mass flowrate into the RCS

. in ,

m, =

mass flowrate out of the RCS i

g

=

boron mass flowrate-

!- m, =

water mass flowrate !

g = boron mass !

m, = water mass- ,

C,, = boron concentration going into RCS C, =

boron concentration going out of RCS I Co =

initial boron concentration C(t) =

boron concentration'as a function of time I Cacs =

RCS boron concentration {

l Simolifyina Assuuntions During a feed-and-bleed operation, the RCS can be pictured as a closed container having.a certain volume, a'certain ,

mass, and an initial boron concentration. Coolant is added-

'ABB Combustion Engineering Nuclear Services Page.Al-1 of Al-6'

! i

._ . . _ _ _. _ , ..__ _ _ _ _ _ . - ._ . . _ . . . _ _ . . . ,. _ - _.- a

noRIC ACID CDsCENTRATION REDUCTIOst EFFORT CEN-602, REY.2 TECIDtICAL BASES AND OPERATIONAL ANALYSIS t

dj, = doye = (6,)j, = (6,) ,,, (3.0)

Finally, if it is assumed that the boron which is added to the RCS mixes completely and instantly with the entire l

RCSmass, the concentration of the fluid coming out of the system will be equal to the system concentration, or i

C,,, = C,c3 (4. 0 )

Derivation l

The rate of change of boron mass within the RCS is equal to :

the mass of boron being charged into the system minus the mass of boron leaving via letdown. In equation form, this becomes:

d

}N b RC5 " in bC s , - b oueCoue l

From Equation 3.0, (m3 ) ,c , = hjo (Cj, - C,,e) = (m,) f, ( C 3 , - C,,,) (5.0) i The concentration of boron in the RCS i.e,. the weight i fraction of boron, is defined as follows:

i "b

C*=

C (m3 + m,) ,c,

]

I Since m,>> g , then ABB Combustion Engineering Nuclear Services Page Al-3 of Al-6 l l

I 3

, BORIC ACID CONCElmtATION REDUCTION EFFORT CEN-602, REY.2 TECENICAL BASES AND OPERATIONAL ANALYSIS ;

i i

C** = (m,),a t

where (g),c, is a constant for a constant system temperature. ,

The rate of change of the RCS concentration is therefore d

d E "" ** (6.0) g C,a =

Substituting Equation 5.0 into Equation 6.0 yields the t

following:

_d_ g"" , %,) in W n - C,,e) i dc ( m ,) ,a ,

i and from Equation 4.0 l

l

_d_ c"" , @v) in Mn-Cam) i (7.0) dc (m),a !

a Solving Equation 7.0 for concentration yields-

)

I ABB Combustion Engineering Nuclear Services Page Al-4 of Al-6 i

I-BORIC ACID o0NCENTRATION REDU.XION RFFORT CEN-602, REY.2 TECIDrICAL BASES AND OPERATIONAL ANALYSIS d "" = ' '"

dt (C3 - C,a) (m,) ,a or C( t)

I Id c o, C,, - C,a

=

(m,),a[,de {

i t

I 1

Integrating from some initial concentration C, to some final !

concentration C(t) and multiplying through by a minus one gives the following:

I C(0)

In (C,a - C3) =- " '"

c C(c) I"wI RN j

' C( t) -Cin (sh,) ,,

in =- t Co -C,1 (m,) ,a l

I continuing to solve for C(t), this equation becomes:

ABB Combustion Engineering Nuclear Services Page Al-5 of Al-6

f f

f noR3(: ACID CONCENTRATIcer REDUCTIO 0f EFFORT CEBI-602, REY.2 TECB ICAL BASES AND OPERATIONAL ANALYSIS '

C(c) - Cj, , _gy, f gg, C a - Cj, or C(t) = Cj, + ( C a- c ,) je -(M Ja /t (@ * ' (8.0) l If we define the time constant t to be as follows:

i T= (#") "

($w) in l

! then Equation 8.0 becomes i

i I C( t) = Ca (e-*/') + Cj , (1-e-*/') (9,o) i

\

I ABB Combustion Engineering Nuclear Services Page Al-6 of Al-6

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS Appendix 2 A Proof that Final System Concentration is Independent of System Volume Purpose of Definitions This appendix presents a detailed proof that during a plant cooldown with charging only as necessary to makeup for coolant contraction, the final system concentration that results using a given boration source concentration will be independent of the total system volume. For this proof, the following definitions were used:

c, =

initial boron concentration Plant 1 ng, =

initial boron mass Plant 1 j n(g =

initial water mass Plant 1 l c, =

final boron concentration Plant 1 l c, =

boron concentration of makeup solution Plant 1 ng, =

mass of boron added Plant i ny, =

mass of water added Plant 1 ng, =

final boron mass Plant 1 Ci =

initial boron concentration Plant 2 Fy =

initial boron mass Plant 2 M,g =

initial water mass Plant 2 l C, =

final boron concentration Plant 2 C, =

boron concentration of makeup solution Plant 2 F(, =

mass of boron added Plant 2 M. =

mass of water added Plant 2 l

l ABB Combustion Engineering Nuclear Services Page A2-1 of A2-6 l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECENIcAL BASES AND OPERATIONAL ANALYSIS Proof For this proof, consider two plants at the same initial temperature, the same initial pressure, and the same initial boron concentration. One plant, Plant 2, has exactly i twicethe system volume as the other plant, Plant 1. l Initially, boron concentration Plant 1 = boron concentration Plant 2, or l

1

1. bl cf = Cj = Nbi

Nvi =

(1.0) l Mg3 + M ag l

Since the volume of Plant 2 is twice that of Plant 1, N = 2mg. Substituting this relationship into EquatJ_an 1.0 and solving yields the following: I l

Nbi ,

N, g l N bi *N ri Nbi

EM wi l

and NbiM y1 + 2mggmaj = m Mg3 g3 + m,gMg3 and M3f = 2m 33 (2.0)

Therefore, the initial boron mass in Plant 2 is exactly ABB Combustion Engineering Nuclear Services Page A2-2 of A2-6

= --

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS !

twice the initial boron mass in Plant 1.

)

During the cooldown process for Plant 1, the final boron mass in the system will equal the initial boron mass plus the added boron mass, or .

m3f=m3+mu 3 (3.0)

If, during this cooldown process, charging is performed only I as necessary to makeup for coolant contraction, water and boron will be added only as space is made available in the system due to coolant shrinkage. The final boron concentration from Equation 3.0 can therefore be expressed as follows:

m3 , = (m33 + mu + m,j + m,] #'

b m3j +m u+mj+m,,

a If concentration is expressed in terms of weight percent, this last equation becomes ,

i mf=

3 (m3 3 + ma + m,j + m,,) cf (4.0)

Similarly, the remaining two components of Equation 3.0 become N3 j = (m3, + m,j) c3 (5.0) and i

i 1

ABB Combustion Engineering Nuclear Services Page A2-3 of A2-6

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS mu = (mu + my ,) c , (6. 0 )

Substituting Equations 4.0, 5.0, and 6.0 into Equation 3.0 and solving for the final concentration yields the following:

(m3 ; + m f) c3 + (mu + m,,) c*

(7 . 0) m,, + mu + m,3 + m,,

For Plant 2, Equation 7.0 becomes (H,3 + M,3) Ci + (Mu + M,,) C, Cf= Mgg + Mu + M ,3 + M ,,

(8.0)

During a cooldown, the shrinkage mass, i.e., the mass of fluid that must be added to the system in order to keep pressurizer level constant, is calculated by dividing the system volume by the change in specific volume, or

, " * , System Volume Plant 1 {g,o}

b Specific Volume and y tem Volume Plant 2 M"*

g39,9y b Specific Volume ABB Combustion Engineering Nuclear Services Page A2-4 of A2-6

-i acaIc ACID coscsurmATIos REDUCTION EFFORT CEN-602, REY.2 i TscaNICAL BASES AND OPERATIONAL ANALYSIS I

where System Volume Plant 1 = (1/2) System Volume Plant 2. I For a given cooldown, dividing Equation 9.0 by Equation 10.0 f gives the following-l (11.0)

N, = 2m, ,

i In addition, if'the charging source for both plants is at !

the same concentration and temperature, C, = c, _12.0)

(

and ,

i M3 , = 2mu (13.0) I Substituting Equations 2.0, 11.0, 12,0, and 13.0 into l

Equation 8.0 yields the following:

l Cf= (2m ,2m 3 + 2m,3) cf + (2mu + 2m.) e, = c f

3 3 + 2mu + 2m,j + 2m, ,

l i

Since the initial concentrations are the same, ci = ci, and l since Plant 2 is twice as'large as Plant 1, Mg= 2 m,i , !

)

l

- ABB Combustion Engineering Nuclear Services Page A2-5 of A2 I i

i

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

BORIC ACID oONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS (2m3 , + 2m,f) cf +

Cr" 2m33 + 2m (2m3 , +2m y

) c, , c#

3 , + 2m,j + 2m, or Cf=cf (14.0) ,

i Therefore, for a cooldown where pressurizer level is maintained constant, the final boron concentration for Plant

~

2 is equal to the final boron concentration for Plant 1, ,

i.e., the change in boron concentration is independent of the exact system volume.

l 1

l I

ABB Combustion Engineering Nuclear Services Page A2-6 of A2-6 l l

. .~ . ,_, . -. .

l i

l :

surc acro casessraarros aspectros arroar CEN-602, REY.2 !

recusreaL masas aus opezarrosnL awarrars j i

Appendix 3 l; l

I Methodology for calculating Dissolved Boric Acid l - per Gallon of Water l Purpose j i

l The purpose'of this appendix is to show the methodology used i

to calculate the mass of boric acid dissolved in each gallon i of water for solutions of various boric acid concentrations..

Two solution temperatures were.used: the minimum allowable l RWT temperature of 50*F and a boric acid-makeup temperature i of 70*F, with no heaters in the BAST.-

I !

Methodoloav and Results l

Boric acid concentration expressed in terms of weight percent is defined as follows:

i

)

1 C= **## *f b**A' ^'A8 x 100 total solution mass i

1 l

or

L C= mass of boric acid (mass of boric acid) + (mass of water) x100 (1.0)

L ABB Combustion Engineering Nuclear Services - Page A3-1.of.A3-3 y

t.

, . . _ . --- ,, - . . . . - * , . - - . . - , , ,, ....----..,m. *._ ._.

l P

i e

i 50aIC ACID CONCENTRATIGE REDUCTION EFFORT CEN-602, REY.2 l TsCanICAL aAsas AxD OPERATIONAL ANALYSIS Defining the mass of boric acid as s h and the mass of water f as n,, and substituting into equation (1.0) gives the l following: [

C= " x 100 au + m, ;

i or i l

(c) x (m.,)

mu= ,

(2.0) f

! From Appendix A of Reference 4.5, the density of water at ;

70 F is 8.3290 lb,/ gallon and at 40*F is 8.351 lb,/ gallon.

Using these figures and Equation 2.0, the mass of boric acid per gallon of solution is calculated as shown in the i

following table- >

l l

-1

)

l l

t l

1 l

ABB Combustion Engineering Nuclear Services Page A3-2 of A3-3 -j

\

i i

BORIC ACID CoNCIDITRATION REDUCTION KFFoRT CEN-602, REV.2 TECHNICAL EASES AND OPERATIONAL ANALYSIS 1

. TABLE A3-1 CONCENTRATION OF BORIC ACID IN WATER l

Concentration Mass of Acid Der Gallon Source Boric Acid Boron lb,/ gal ummmmmmmmmm M RWST 1.42993 2500 0.12083 RWST 1.45852 2550 0.12328 RWST 1.48712 2600 0.12573 RWST 1.51572 2650 0.12819 RWST 1.55432 2700 0.13064 l BAT 3.50 6119 0.30209 BAT 3.625 6338 0.31328 l BAT 3.75 6556 0.32451 l

BAT 3.875 6775 0.33576 BAT 4.0 6993 0.34704 NOTE: For Human Factors reasons, the revised Technical Specifications will contain boron concentration in terms of ppm Boron. The boron concentration values have been rounded to the nearest 10 ppm for i Human Factors considerations.

i I

ABB Combustion Engineering Nuclear Services Page A3-3 of A3-3

noRIc ACID concurraATION REDUCTION EFFORT CEN-602, REY.2 TsenNIcAL nasas AND OPERATIONAL ANALYSIS 1 l l Appendix 4 i Methodology for Calculating the Conversion Factor i Between Weight Percent Boric Acid and ppm Boron l l

1 i

Purpose The purpose of this appendix is to show the methodology used '

to derive the conversion factor between concentration in terms of weight percent boric acid and concentration in l terms of parts per million (ppm) of naturally occurring l boron. I I

I Results For any species (solute) dissolved in a solvent, a solution having a concentration of exactly 1 ppm can be obtained by dissolving 1 lb, of solute in 999,999 lb, of solvent. An aqueous solution having a concentration of 1 ppm boric acid, '

therefore, is obtained by dissolving 1 lb, of boric acid in 999,999 lb, of water, or l

1 ppm = 1 lb, boric acid 1 lb, boric acid

=

i 1 lb, boric acid + 999,999 lb, water 10' lb, solution i

l I

ABB Combustion Engineering Nuclear Services Page A4-1 of A4-2 l

l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS For any species (solute) dissolved in some solvent, a solution having a concentration of 1 weight percent (w/4) can be obtained by dissolving 1 lb, of solute in 99 lb, of j solvent. An aqueous solution having a concentration of 1 weight percent boric acid, therefore, can be obtained by ;

dissolving i lb, of boric acid in 99 lb, of water, or )

l 1 wtt , 1 lb, boric acid ,

1 lb, boric acid 100 1 lb, boric acid + 99 lb, water 100 lb, solution ;

Dividing these last two equations yields a ratio of 10', or 1 weight percent boric acid = 10,000 ppm boric acid To convert from ppm boric acid (weight fraction) to ppm boron (weight fraction), multiply Equation 1.0 by the ratio of the molecular weight of boric acid (naturally occurring l H3 B03 ) to the atomic weight of naturally occurring boron.

From the Handbook of Chemistry and Physics, CRC Press, 1 weight percent boric acid = (10,000) 10*81 ppm boron 61.83 or 1 weight percent boric acid = 1948.34 ppm boron l

ABB Combustion Engineering Nuclear Services page A4-2 of A4-2

1 l

l BORIC ACID CONCENTRATION REDUCTION EFPORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS I

l l Appendix 5 Bounding Physics Data Inputs l

l l

t The methodology used to compute core reactivity and the required changes in boron concentration resulting therefrom

]

are described in this appendix. This methodology was used to conservatively bound the reactivity effects of the cooldown described in Section 2.2.1.1 of this report. The l cooldown scenario is summarized in the following paragraphs, I along with a discussion of the methods used to compute the l changes in boron concentration made necessary by the cooldown.

Cooldown Scenario and Assumotions The following scenario was evaluated to establish the bounding boron concentrations which have been used in this report.

1

1. Shutdown Margin Requirements: )

200*F < T,y, < 547'F

_ 1600 pcm T,y, < 200*F 1000 pcm

2. Reactor is initially at Hot Full Power (HFP),

equilibrium xenon and samarium conditions, at a cycle burnup which would allow HFP operation at an RCS concentration of 0 ppm boron, with the control rods at the Technical Specification insertion limits and xenon at peak conditions. This combination of conditions maximizes the change in boron concentration required to ABB Combustion Engineering Nuclear Services Page AS-1 of AS-10

4 l

1 BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS i

maintain Shutdown Margin (SDM) and to compensate for a reactor trip and subsequent cooldown to cold, xenon free conditions.

3. The most reactive control rod is assumed to be stuck in the fully withdrawn position and is therefore not available for shutdown reactivity control.

4. At t=0, the reactor is tripped and held at Hot Zero Power (HZP) conditions (547'F) for 8.0 hours0 days 0 hours 0 weeks 0 months . (This allows xenon to peak.)

5. A dilution is started which reduces the RCS boron concentration to O ppm.

6. At t=8.0 hours0 days 0 hours 0 weeks 0 months , a plant cooldown from 547'F to 135'F is initiated, at an average rate of 10*F/hr. (At temperatures below 200*F, it is assumed all xenon has decayed and that the core is xenon free).

The use of assumptions 4, 5, and 6 ensure that the maximum rate of xenon decay is accounted for in the bounding boron calculations. The peak xenon concentration is reached approximately eight (8) hours i

after reactor shutdown.

l l

At times beyond 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months , the reactor must be borated to compensate for the decay of xenon. Thus, the bounding boron concentrations which are calculated must offset j the the positive reactivity contribution from both the cooldown and the xenon decay.

ABB Combustion Engineering Nuclear Services Page AS-2 of AS-10

l I

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS

7. The samarium concentration is assumed to remain constant for the entire scenario. This is a !

j conservative assumption which increases the calculated boron requirements, since the negative reactivity worth !

of the samarium increases with time after shutdown. l

8. The boron calculations calculated were normalized to an l End-of-Life (EOL) , HFP MTC of -45. 0 pcm/ *F. This was :

done to ensure that the calculated boron calculations will be bounding for future cycles. In the current Technical Specifications, the most negative MTC is l -40.0 pcm/*F, but evaluations are under way to revise l

this Technical Specification to -45.0 pcm/*F.

The limiting boron concentration curves were calculated for l the four (4) most recent Sequoyah cycles, i.e., Unit 1, l Cycles 5 and 6, and Unit 2. Cycles 5 and 6. The results of i the limiting boron concentrations calculated using actual core physics parameters and normalized to the most negative MTC value of -45.0 pcm/'F are shown in Figure A5-1. The ,

limiting boron curve used in this report was determined from l the most restrictive normalized cycle calculations (Unit 2, Cycle 5). This curve is shown in Figure AS-2. The curve of required boron concentration calculated as a function of temperature assuming that the plant is held at 547'F until xenon has decayed is shown in Figure AS-3.

1 i

Description of Methodoloov The bounding changes in boron concentration which are required to maintain SDM during the conservative post-trip i cooldown were calculated using the standard Westinghouse ABB Combustion Engineering Nuclear Services Page AS-3 of A5-10 l

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS shutdown margin procedure. A brief description of this procedure follows.

For a given fuel cycle, a table of required boron concentration versus temperature and average burnup is utilized to maintain SDM during sr:utdown and cooldown. The values of boron concentration in the table are calculated using the following assumptions:

1. No xenon or samarium present in core,

2. Most reactive control rod stuck out of core,

3. The maximum Technical Specification SDM of 1600 pcm is present, and

4. A 100 ppm factor of safety is included in the maximum boron concentrations as an allowance for calculational uncertainty.

Implicitly included in the table are the changes in total temperature defect and rod worth associated with changes in temperature and burnup.

Corrections are made to the values in this table to account for the presence of xenon and samarium and for the change in required SDM which occurs at temperatures below 200*F, and to normalize the data to the most negative moderator ;

temperature coefficient (MTC) of -45.0 pcm/*F. l The xenon worth correction is determined from a table of total xenon worth as a function of equilibrium power level and time following plant trip for EOL conditions and is calculated with no boron.

ABB Combustion Engineering Nuclear Services page AS-4 of AS-10

l i

i BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS !

The samarium worth correction is determined from a table of total samarium worth as a function of power level before i trip and time following plant trip, and is also calculated with no boron. Because the negative reactivity worth of samarium increases following a plant trip, the value of samarium worth at the time of trip was used in all calculations as an additional conservatism.

A correction of 600 pcm is made to account for the reduction in the Technical Specification SDM requirement for temperatures below 200*F.

A reactivity correction versus temperature is made to normalize the actual most negative EOL MTC to the proposed most negative Technical Specification MTC value of

-45.0 pcm/*F. This was done conservatively by linearly applying the difference between the predicted actual most-negative MTC and -45.0 pcm/*F times the cooldown temperature.

Integral boron worths are used to translate the previously discussed reactivity corrections into changes in boron concentration. These integral boron worths are obtained from a table of integral boron worth vs. boron concentration for temperatures ranging from 68'F to 547"F calculated at EOL conditions. The integral worth is used to determine a correction factor for xenon and samarium worth at the maximum boron concentration and to determine the final boron I concentration after accounting for the xenon and samarium, any change in SDM requirement, and the maximum Technical Specification EOL MTC normalization.

ABB Combustion Engineering Nuclear Services ~

page AS-5 of A5-10

i t

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REY.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS The final minimum boron concentration as a function of temperature is determined as follows:

i

a. The maximum boron concentration is determined from the l table of maximum boron concentration. !

l

b. The reactivity contributions of boron-free xenon and l samarium, the SDM requirements, and the most negative j MTC normalization are determined.

l

c. THe integral boron worth for the maximum boron is read from the table at the shutdown temperature.

d. A correction factor is determined from this worth and is applied to the xenon and samarium worth to account i for the reduction in xenon and samarium worth due to i

the presence of boron.

e. The corrected xenon and samarium worth, the SDM requirement correction, and the most negative MTC l

\

normalization reactivity are subtracted from the l integral boron worth to obtain the net reactivity required to supply minimum SDM. 1 l

f. With this value, the resulting boron concentration required to provide SDM is read from the integral boron worth table.

I 1

ABB Combustion Engineering Nuclear Services Page AS-6 of A5-10 i

l

I

\

l BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSIS l y.e.rification of Future Reloads The methodology discussed above will be applied to future reload cores to ensure that the required boron concentrations calculated for the reload are bounded by the limiting curve (Figure AS-2) given in this report.

l I

i l

i ABB Combustion Engineering Nuclear Services Page AS-7 of A5-10

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 TECHNICAL BASES AND OPERATIONAL ANALYSES SQN REQUIRED BORON . CONCENTRATIONS 10 F/HR COOLDOWN U1C5, U1C6, U2C5, U2C6

, (Peak Xenon) 1400 '

B S

o 1200 --

! g; .

N

.i000 - !

l i- i '

i C A

- p 8 800 - - - - -

, - j u 600 --;----

400 - -

l ' - -

-l-Q ,

T ( I f" 200 --

j 0-550 500 450 400 350 300 250 200 150 DEGREES F U1C6 Case 1 : U2 C 5 C a s e t-*- U1CS Case 1-*- U1C6 Case 2

+ U205 Case 2-+- U1CS Case 2+ U2C6 Case 2 U2C6 Case 1 l Case 1 normalized to -45 pcm/F MTC Case 2 utilizes predicted EOL MTC ABB COMBUSTION ENGINEERING NUCLEAR SERVICES PAGE AS-8 of AS 10

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV.2 i TECHNICAL BASES AND OPERATIONAL ANALYSES 3

Limiting SQN Cooldown Curve 10 F/HR COOLDOWN (Peak Xenon) 1400 l t

i 1200 -- --- -- ' - - - - - - - -

] ;

d

^

8 I 0 1000 ~ ~ - - - - - '--' - - - - * - - '

N

- T6*Mh pW~ ~

$47 Q 2 L5. ..

800 - - - - - -. .... . 5 0 b 8

n 450 Si9 E i ! 40U 7d3 n

T goo . -...... ; - - . . . . .

.;...--...... 3sb . gf g ....-

i n

A i 300 96 T . 250 10,0 fN 400 --

26k 'i'i40

~~

200, 11 El8 200 -- -- - - - - - - -

- - - ---- 135. -1213 ___

! 7 0 ,

575 525 470 425 375 325 275 225 175 DEGREES F 4

ABB COMBUSTION ENGINEERING NUCLEAR SERVICES PAGE AS-9 of AS-10

. . _ _ _ . . _ _ _ _ . _ _ _ . _ _ . _ _ _ . _ - _ _ ___ _ _ __m______._____-m_________-__________m _--__m

_________e--

BORIC ACID CONCENTRATION REDUCTION EFFORT CEN-602, REV 2 TECHNICAL BASES AND OPERATIONAL ANALYSES

-Limiting. SQN Cooldown Curve No xenon (Peak Xenon) 1.400 . :

I' #'

1200 -

a ,

f 3o99 - . . . . ~ . . . _ - - - ... .. . .

. . Tdhi p'~ "%hi

N $47 67h ;

800 - -- - - - - - - -- - -- - - -- - - --- - - --- 50o 737 --

8 450 868 N

j ;

400 976 N

T 600 - =l ------*- ' - - - ~ -- - ~

L--350' 10 4 --- -

R 300 110

$ '250 116b 400 - - -

f 20 d"~ ~1212 '

N 200 115$

-135 - .t2 2 L _._ .

200 - -- -- - - - - - - - - - - - --- --- ---

0 . ;

575 525 475 425 375 325 275 225 175 DEGREES F.

ABB COMBUSTION ENGINEERING NUCLEAR SERVICES . PAGE A5-10 of A5-10 i

__.___.__.__m_ ..m.-_ _ _ _ _ _ . _ . _ _ . . _ _ ._._.....__.m_m. ._._____m______...-,_.,m c.-v.. em.,- .%.- -,,em,-%, ..--.,3..-r-...-.,,w-, --e-_s~ -.m, . , . - *,.,-,,-..,v.-w.~,..,,..,,.~.-,,,,e,,.sm.., ..m..,,,,,.e,-r

ML20044B996

Text

1.0 INTRODUCTION

3.1 INTRODUCTION

4.0 REFERENCES

1.0 INTRODUCTION

3.1 INTRODUCTION

4.0 REFERENCES

Navigation menu

Search