ML20216B972

Proposed Tech Specs 3/4.6.5 Re Ice Condenser Reduction of Required Ice Weight

ML20216B972
Person / Time
Site:	Catawba
Issue date:	04/08/1998
From:	DUKE POWER CO.
To:
Shared Package
ML20216B954	List: ML20216B950 ML20216B972
References
NUDOCS 9804140219
Download: ML20216B972 (46)

Text

.

CONTAINMENT SYSTEMS

( 3/4.6.5 ICE CONDENSER ICE BED LIMITING CONDITION FOR OPERATION 3.6.5.1 The ice bed shall be OPERABLE with:

a. The stored ice having a boron concentration of at least 1800 ppm boron as sodium tetraborate and a pH of 9.0 to 9.5,

b. Flow channels through the ice condenser,

c. A maximum ice bed temperature of less than or equal to 27*F, 2

d. A total ice weight of at leasti,380,5%d75,252 pounds at a 95% level of confidence, and e, 1944 ice baskets.

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

ACTION:

With the ice bed inoperable, restore the ice bed to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUT-DOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

SURVEILLANCE RE0VIREMENTS 4.6.5.1 The ice condenser shall be determined OPERABLE:

(

a. At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by using the Ice Bed Temperature Monitor-ing System to verify that the maximum ice bed temperature is less than or equal to 27*F,

b. At least once per 9 months by:

1) Chemical analyses which verify that at least nine representative samples of stored ice have a boron concentration of at least 1800 ppm as sodium tetraborate and a pH of 9.0 to 9.5 at 25*C; and

2) Verifying, by a visual inspection of at least two flow passages per ice condenser bay, that the accumulation of frost or ice on flow passages between ice baskets, past lattice frames, through the top deck floor grating, or past the lower inlet plenum support

( 9804140219 980400 PDR ADOCK 05000413 P PDR CATAWBA - UNIT 1 3/4 6-33 Amendment No.

a CONTAINMENT SYSTEMS SURVEILLANCE RE0VIREMENTS (Continued) structures and turning vanes is restricted to a thickness of less than or equal to 0.38 inch. If one flow 3assage per bay is found to have an accumulation of frost or ice witi a thickness of greater than or equal to 0.38 inch, a representative sample of 20 additional flow passages from the same bay shall be visually inspect 1d. If these additional flow passages are found acceptable, the suiveillance program may proceed considering the single deficiency as unique and acce) table. More than one restricted flow passage per bay is evidence of a) normal degradation of the ice condenser.

c. At least once per 18 months by:

g Weighing a representative sample of at least 14 e baskets and verifying that each basket contains at least 1t73 lbs of ice. The representative sample shall include six baskets from each of the 24 l ice condenser bays and shall be constituted of one basket each from Radial Rows 1, 2, 4, 6, 8, and 9 (or from the same row of an adjacent bay if a basket from a designated row cannot be obtained for weighing) within each bay. If any basket is found to contain less tha3f1W3 pounds of ice, a representative sample of 20 additional fasketsfromthesamebayshallbeweighed.Theminimumaverage pcs weight of ice from the 20 additional baskets and the discrepant basket shall not be less than 1Na pounds / basket at a 95% level of confidence. IM9 l The ice condenser shall also be subdivided into 3 groups of baskets, '

as follows: Group 1 - Bays 1 through 8, Group 2 - Bays 9 through 16, and Group 3 - Bays 17 through 24. The minimum average ice weight of the samale baskets from Radial Rows 1, 2, 4, 6, 8, and 9 in each group s1all not be less than 1N3 pounds / basket at a 95% level of confidence. IR9 l The minimum total ice condenser ice weight at a 95% level of confidence shall be calculated using all ice basket weights determined during this weighing program and shall not be less than

-2.d75.252 pounds.

7 ,33cp% l

d. At least once per 40 months by lifting and visually inspecting the accessible portions of at least two ice baskets from each one-third of the ice condenser and verifying that the ice baskets are free of detrimental structural wear, cracks, corrosion or other damage. The ice baskets shall be raised at least 12 feet for this inspection.

CATAWBA - UNIT 1 3/4 6-34 Amendment No.

CONTAINMENT SYSTEMS BASES 3/4.6.5 ICE CONDENSER The requirements associated with each of the components of the ice con-denser ensure that the overall system will be available to provide sufficient pressure suppression capability to limit the containment peak pressure tran-sient to less than 14.7 psig during LOCA conditions.

3/4.6.5.1 ICE BED The OPERABILITY of the ice bed ensures that the required ice inventory will: (1) be distributed evenly through the containment bays, (2) contain sufficient boron to preclude dilution of the containment sump following the LOCA, and (3) contain sufficient heat removal capability to condense the Reactor Coolant System volume released during a LOCA. These conditions are consistent with the assumptions used in the safety analyses

\\% Dw:sytkiNcwk c;op d The minimum weight figure of -1N3. pounds of ice per basket contains a 1st conservative allowance for ice loss through sublimationA The minimum total g M44Md52 pounds of ice also contains an additional 1.1% conserva-tive allowance to account for systematic error in the weighing instruments.

p b the event thct ebte ved abl%ti= rete cre c:;=1 to or icwcr than design gg p predictions af ter 3 years of :pcration, thc ainimum ic; baskcts eight sey be adj=ted d= =rd.

( 3/4.6.5.2 ICE BED TEMPERATURE MONITORING SYSTEM The OPERABILITY of the Ice Bed Temperature Monitoring System ensures that the capability is available for monitoring the ice temperature. In the event the system is inoperable, the ACTION requirements )rovide assurance that the ice bed heat removal capacity will be retained wit 1in the specified time limits.

3/4.6.5.3 ICE CONDENSER DOORS The OPERABILITY of the ice condenser doors and the requirement that they be maintained closed ensures that the Reactor Coolant System fluid released during a LOCA will be diverted through the ice condenser bays for heat removal and that excessive sublimation of the ice bed will not occur because of warm air intrusion.

If an Ice Condenser Door is not capable of opening automatically, then system function is seriously degraded and immediate action must be taken to restore the opening capability of the door. Not capable of opening automati-cally is defined as those conditions in which a door is physically blocked from opening by installation of a blocking device or by obstruction from temporarily or permanently installed equipment. Impairment by ice, frost or debris is considered to render the doors inoperable but capable of opening automatically since these types of conditions will result in a slightly greater torque necessary to open the doors or a slight delay in door opening.

CATAWBA - UNIT 1 B 3/4 6-9

Attachment ib Revised Current Technical Specifications Pages for Catawba Unit 2 l

1 l

l

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l l

'; 'l CONTAINMENT SYSTEMS

/

(

4 l 3/4.6.5 ICE CONDENSER '

ICE BED

@g. e LIMITING CONDITION FOR OPERATION f

N h,

f 3.6.5.1 The ice bed shall be OPERABLE with: .

a. The stored ice having a boron concentration of at least 1800 ppm ll

!?

boron as sodium tetraborate and a pH of 9.0 to 9.5,

[

b. Flow channels through the ice condenser, h[

c. A maximum ice bed temperature of less than or equal to 27'F,

d. h 330 m  !

A total ice weight of at least 2,175,,252 pounds at a 958: level of

, confidence, and g!*j'

., e. 1944 ice baskets.

S t APPLICABILITY: MODES 1, 2, 3, and 4. I

)g '

ACTION:

i-With the ice bed inoperable, restore the ice bed to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> orwithin DOWN be in the at least HOT30 following STANDBY hours. within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUT- I SURVEILLANCE REQUIREMENTS

( 4.6.5.1 The ice condenser shall be determined OPERABLE:

a. At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by using the Ice Bed Temperature Monitor- )

g ing System to verify that the maximum ice bed temperature is less g than or equal to 27*F, g

b. At least once per 9 months by: I, .

J

1) Chemical analyses which verify that at least nine representative samples of stored ice have a boron concentration of at least 4 1800 ppm as sodium tetraborate and a pH of 9.0 to 9.5 at 25'C;

.lp and  :

1 (

2) Verifying, by a visual inspection of at least two flow passages #

per ice condenser bay, that the accumulation of frost or ice on  ;,

flow passages between ice baskets, past lattice frames, through '

the top deck floor arating, or past the lower inlet plenum support H y

n  ? 1 a\  ;

' l

'e 1

l l

CATAWBA - UNIT 2 3/4 6-33 Amendment No.

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'w . g l CONTAINMENT SYSTEMS ,,

3, SURVEILLANCE REQUIREMENTS (Continued) (

). .

M structures and turning vanes is restricted to a thickness of less

+jl than or equal to 0.38 inch. If one flow 3assage )er bay is found to  :

have an accumulation of frost or ice wit 1 a thic cness of greater than

,(:, , or equal to 0.38 inch, a representative sample of 20 additional flow  !

3 passages from the same bay shall be visually ins)ected. If these "

d additional flow passages are found acce table, tie surveillance  :

d program may proceed considering the sin le deficiency as unique and '

d acceptable. More than one restricted flow passage per bay is evidence of abnormal degradation of the ice condenser.

c. At least once per 18 months by: p Weighing a representative sample of at least 144 ce baskets and verifying that each basket contains at least lbs of ice. The g representative sample shall include six baskets from each of the 24 ,

ice condenser bays and shall be constituted of one basket each from Radial Rows 1, 2, 4, 6, 8, and 9 (or from the same row of an adjacent

bay if a basket from a designated row cannot be obtained for weighing) within each bay. If any basket is found to contain less t pounds of ice, a representative sample of 20 additional j ts from the same bay shall be' weighed. The minimum average p weight of ice from the 20 additional baskets and the discrepant basket shall not be less than 12M pounds / basket at a 95% level of l confidence. 11%

(

The ice condenser shall also be subdivided into 3 groups of baskets, as follows: Group 1 - Bays 1 through 8. Group 2 - Bays 9 through 16, and Group 3 - Bays 17 through 24. The minimum average ice weight of

\ the sam)1e baskets from Radial Rows 1, 2, 4, 6, 8, and 9 in each group s1all not be less than .12M pounds / basket at a 95% level of A confidence. W l The minimum total ice condenser ice weight at a 95% level of i confidence shall be calculated using all ice basket weights y detennined during this weighing program and shall not be less than Y 2.475.252 pounds. l4'l ;

.j.} 23 65c),Wf, "!

d. At least once per 40 months by lifting and visually inspecting the -

1 accessible portions of at least two ice baskets from each one-third ,

of the ice condenser and verifying that the ice baskets are free of l

. detrimental structural wear, cracks, corrosion or other damage. The l 9

a ice baskets shall be raised at least 12 feet for this inspection.  :

[d

.d f l

CATAWBA - UNIT 2 3/4 6-34 Amendment No.

.1

b.

.. ' ' CONTAINMENT SYSTEMS

.. BASES 3/4.6.5 ICE CONDENSER

~

The requirements associated with each of the components of the ice con-denser ensure that the overall system will be available to provide sufficient pressure suppression capability to limit the containment peak pressure tran- I sient to less than 14.7 psig during LOCA conditions.

3/4.6.5.1 ICE BED The OPERABILITY of the ice bed ensures that the required ice inventory I will: (1) be distributed evenly through the containment bays, (2) contain sufficient boron to preclude dilution of the containment sump following the LOCA, and (3) contain sufficient heat removal capability to condense the Reactor Coolant System volume released during a LOCA. These conditions are consistent with the assumptions used in the safety, anal .

tiqq Avri ads cip pod M.pp5bco ~The minimum weight figure of ma pounds of ice per> basket contains a ,152 ive allowance for ice loss through sublimation. The minimum total  !

weight 2,US,250 pounds of ice also contains an additional 1.1% conserva-tive allowance to account for systematic error in the weighing instruments. j

-  : th: :=:t that tere:d relhetien reter are :;21 t: er .nr ther, i:;igr, 70 # 2 0 Y ' #

1. 2 2# M b 5.55bf$$23N!I3

. , . . _ . _ _ . . . . . . p t

(- 3/4.6.5.2 ICE BED TEMPERATURE MONITORING SYSTEM J

The OPERABILITY of the Ice Bed Temperature Monitoring System ensures that {

- the capability is available for monitoring the ice temperature. In the event

• the system is inoperable, the ACTION requirements provide assurance that the ice bed heat removal capacity will be retained within the specified time limits.

3/4.6.5.3 ICE CONDENSER DOORS The OPERABILITY of the ice condenser doors and the requirement that they ,

be maintained closed ensures that the Reactor Coolant System fluid released r

c during a LOCA will be diverted through the ice condenser bays for heat removal 1 7 and that excessive sublimation of the ice bed will not occur because of wann 1

$; air intrusion.

c.

If an Ice Condenser Door is not capable of opening automatically, then

@% system function is seriously degraded and immediate action must be taken to P restore the opening capability of the door. Not capable of opening automati-cally is defined as those conditions in which a door is physically blocked j from opening by installation of a blocking device or by obstruction from g temporarily or pennanently installed equipment. Impairment by ice, frost or x i,1 debris is considered to render the doors inoperable but capable of opening automatically since these types of conditions will result in a slightly  !

greater torque necessary to open the doors or a slight delay in door opening.  !

( l l

CATAWBA - UNIT 2 B 3/4 6-9 l 1

Attachment 2a Reprinted Current Technical specifications Pages for Catawba Unit 1

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4 1 o-CQHTAINMENT SYSTEMS 3/4.6.5 ICE CONDENSER ICE BED

. LIMITING CONDITION FOR OPERATION 3.6.5.1 The ice bed shall be OPERABLE with:

a. The stored ice having a boron concentration of at least 1800 ppm boron as sodium tetraborate and a pH of 9.0 to 9.5,

b. Flow channels through the ice condenser,

c. A maximum ice bed temperature of less than or equal to 27'F,

d. A total ice weight of at least 2,330,856 pounds at a 95% level of l confidence, and

e. 1944 ice baskets.

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

ACTION:

With the ice bed inoperable, restore the ice bed to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUT-  ;

DOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. 1 SURVEILLANCE REQUIREMENTS 4.6.5.1 The ice condenser shall be determined OPERABLE:'  !

a. At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by usinu the Ice Bed Temperature Monitor-ing System to verify that the maximum ice bed temperature is less than or equal to 27*F,

b. At least once per 9 months by:

1) Chemical analyses which verify that at least nine representative samples of stored ice have a boron toncentration of at least 1800 ppm as sodium tetraborate and a pH of 9.0 to 9.5 at 25*C; and

2) Verifying, by a visual inspection of at least two flow passages per ice condenser bay, that the accumulation of frost or ice on flow passages between ice baskets, past lattice frames, through the top deck floor grating, or past the lower inlet plenum support i

i l

l l

1 CATAWBA - UNIT 1 3/46-33 Amendment No.

a .

CONTAINMENT SYSTEMS SURVEILLANCE RE0VIREMENTS (Continued) structures and turning vanes is restricted to a thickness of less than or equal to 0.38 inch. If one flow passage per bay is found to have an accumulation of frost or ice with a thickness of greater than or equal to 0.38 inch, a representative sample of 20 additional flow passages from the same bay shall be visually inspected. If these additional flow passages are found acceptable, the surveillance program may proceed considering the single deficiency as unique and acceptable. More than one restricted flow passage per bay is evidence of abnormal degradation of the ice condenser.

c. At least once per 18 months by:

Weighing a representative sample of at least 144 ice baskets and verifying that each basket contains at least 1199 lbs of ice. The [

representative sample shall include six baskets from each of the 24 l ice condenser bays and shall be constituted of one basket each from Radial Rows 1, 2, 4, 6, 8, and 9 (or from the same row of an adjacent  ;

bay if basket from a designated row cannot be obtained for i weighing) within each bay. If any basket is found to contain less  !

than 1199 pounds of ice, a representative sample of 20 additional j baskets from the same bay shall be weighed. The minimum average i weight of ice from the 20 additional baskets and the discrepant j basket shall not be less than 1199 pounds / basket at a 95% level of I ;

confidence. ,

The ice condenser shall also be subdivided into 3 groups of baskets, as follows: Group 1 - Bays 1 through 8, Group 2 - Bays 9 through 16, '

and Group 3 - Bays 17 through 24. The minimum average ice weight of the sample baskets from Radial Rows 1, 2, 4, 6, 8, and 9 in each '

group shall not be less than 1199 pounds / basket at a 95% level of I confidence.

The minimum total ice condenser ice weight at a 95% level of I confidence shall be calculated using all ice basket weights i determined during this weighing program and shall not be less than ,

2,330,856 pounds. l

d. At least once per 40 months by lifting and visually inspecting the  ;

accessible portions of at least two ice baskets from each one-third of the ice condenser and verifying that the ice baskets are free of detrimental structural wear, cracks, corrosion or other damage. The f ice baskets shall be raised at least 12 feet for this inspection.

CATAWBA - UNIT 1 3/4 6-34 Amendment No.

CONTAINMENT SYSTEMS BASES 3/4.6.5 ICE CONDENSER The requirements associated with each of the components of the ice con-denser ensure that the overall system will be available to provide sufficient pressure suppression capability to limit the containment peak pressure tran-sient to less than 14.7 psig during LOCA conditions.

3/4.6.5.1 ICE BED The OPERABILITY of the ice bed ensures that the required ice inventory will: (1) be distributed evenly through the containment bays, (2) contain sufficient boron to preclude dilution of the containment sump following the LOCA, and (3) contain sufficient heat removal capability to condense the Reactor Coolant System volume released during a LOCA. These conditions are consistent with the assumptions used in the safety analyses.

The minimum weight figure of 1199 pounds of ice per basket contains a 90 pound conservative allowance for ice loss through sublimation during the fuel cycle. The minimum total weight of 2,330,856 pounds of ice also contains an additional 1.1% conservative allowance to account for systematic error in the weighing instruments.

l 3/4.6.5.2 ICE BED TEMPERATURE MONITORING SYSTEM The OPERABILITY of the Ice Bed Temperature Monitoring System ensures that the capability is available for monitoring the ice temperature. In the event the system is inoperable, the ACTION requirements provide assurance that the ice bed heat removal capacity will be retained within the specified time limits.

3/4.6.5.3 ICE CONDENSER D0 ORS The OPERABILITY of the ice condenser doors and the requirement that they be maintained closed ensures that the Reactor Coolant System fluid released during a LOCA will be diverted through the ice condenser bays for heat removal /

and that excessive sublimation of the ice bed will not occur because of warm '

air intrusion.

If an Ice Condenser Door is not capable of opening automatically, then system function is seriously degraded and immediate action must be taken to restore the opening capability of the door. Not capable of opening automati-cally is defined as those conditions in which a door is physically blocked from opening by installation of a blocking device or by obstruction from temporarily or permanently installed equipment. Impairment by ice, frost or debris is considered to render the doors inoperable but capable of opening automatically since these types of conditions will result in a slightly greater torque necessary to open the doors or a slight delay in door opening.

CATAWBA - UNIT 1 B 3/4 6-9

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l Attachament 2b l Reprinted Current Technical specifications Pages for Catawba Unit 2 l

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1 l

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I -

L  !

i l CONTAINMENT SYSTEMS l

l 3/4.6.5 ICE CONDENSER ICE BED LIMITING CONDITION FOR OPERATION 3.6.5.1 The ice bed shall be OPERABLE with:

l a. The stored ice having a boron concentration of at least 1800 ppm l boron as sodium tetraborate and a pH of 9.0 to 9.5, l b. Flow channels through the ice condenser, l c. A maximum ice bed temperature of less than or equal to 27'F,

d. A total . ice weight of at least 2,330,856 pounds at.a 95Ss level of confidence, and l

l. e. 1944 ice baskets.

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

L ACTION: i

!. With the ice bed inoperable, restore the ice bed to OPERABLE status within 48 {'

l hours or be in at least HOT STANDBY within the neat 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUT-DOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

SURVEILLANCE REQUIREMENTS

! 4.6.5.1 The ice condenser shall be determined OPERABLE: l l a. At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by using the Ice Bed Temperature Monitor-  !

l ing System to verify that the maximum ice bed temperature is less  !

l than or equal to 27*F, I

l b. At least once per 9 months by:

1) Chemical analyses which verify that at least nine representative I

( samples of stored ice have a boron concentration of at least 1800 ppm as sodium tetraborate and a pH of 9.0 to 9.5 at 25'C; and i

2) Verifying, by a visual inspection of at least two flow passages I per ice condenser bay, that the accumulation of frost or ice on l flow passages between ice baskets, past lattice frames, through i the top deck floor grating, or past the lower inlet plenum .

support j i

I CATAWBA - UNIT 2 3/46-33 Amendment No.

i l CONTAINMENT SYSTEMS l

SURVEILLANCE RE0UIREMENTS (Continued) l structures 6nd turning vanes is restricted to a thickness of less than or equal to 0.38 inch. If one flow passage per bay is found to have an accumulation of frost or ice with a thickness of greater than or equal to 0.38 inch, a representative sample of 20 additional flow passages from the same bay shall be visually inspected. If these l additional flow passages are found acceptable, the surveillance l

program may proceed considering the single deficiency as unique and acceptable. More than one restricted flow passage per bay is evidence of abnormal degradation of the ice condenser.

c. At least once per 18 months by:

Weighing a representative sample of at least 144 ice baskets and verifying that each basket contains at least 1199 lbs of ice. The j representative sample shall include six baskets from each of the 24 ice condenser bays and shall be constituted of one basket each from Radial Rows 1, 2, 4, 6, 8, and 9 (or from the same row of an adjacent bay if a basket from a designated row cannot be obtained for weighing) within each bay. If any basket is found to contain less than 1199 pounds of ice, a representative sample of 20 additional l baskets from the same bay shall be weighed. The minimum average weight of ice from the 20 additional baskets and the discrepant basket shall not be less than 1199 pounds / basket at a 95% level of l confidence.

The ice condenser shall also be subdivided into 3 groups of baskets, as follows: Group 1 - Bays 1 through 8, Group 2 - Bays 9 through 16, and Group 3 - Bays 17 through 24. The minimum average ice weight of the sample baskets from Radial Rows 1, 2, 4, 6, 8, and 9 in each group shall not be less than 1199 pounds / basket at a 95% level of I confidence.

The minimum total ice condenser ice weight at a 95% level of confidence shall be calculated using all ice basket weights determined during this weighing program and shall not be less than 2,330,856 pounds. j

d. At least once per 40 months by lifting and visually inspecting the accessible portions of at least two ice baskets from each one-third of the ice condenser and verifying that the ice baskets are free of detrimental structural wear, cracks, corrosion or other damage. The ice baskets shall be raised at least 12 feet for this inspection.

CATAWBA - UNIT 2 3/4 6-34 Amendment No. l

l CONTAINMENT SYSTEMS BASES 3/4.6.5 ICE CONDENSER The requirements associated with each of the components of the ice con-denser ensure that the overall system will be available to provide sufficient pressure suppression capability to limit the containment peak pressure tran-sient to less than 14.7 psig during LOCA conditions.

3/4.6.5.1 ICE BED The OPERABILITY of the ice bed ensures that the required ice inventory will: (1) be distributed evenly through the containment bays, (2) contain sufficient boron to preclude dilution of the containment sump following the LOCA, and (3) contain sufficient heat removal capability to condense the Reactor Coolant System volume released during a LOCA. These conditions are consistent with the assumptions used in the safety analyses.

The minimum weight figure of 1199 pounds of ice per basket contains a 90 pound conservative allowance for ice ',oss through sublimation during the fuel cycle. The minimum total weight of 3,330,856 pounds of ice also contains an additional 1.1% conservative allowance to account for systematic error in the  !

weighing instruments. j l

3/4.6.5.2 ICE BED TEMPERATURE MOLITORING SYSTEM The OPERABILITY of the Ice Bed Temperature Monitoring System ensures that j the capability is available for monitoring the ice temperature. In the event the system is inoperable, the ACTION requirements provide assurance that the ice bed heat removal capacity will be retained within the specified time limits.

3/4.6.5.3 ICE CONDENSER DOORS The OPERABILITY Of the ice condenser doors and the requirement that they be maintained closed ensures that the Reactor Coolant System fluid released during a LOCA will be diverted through the ice condenser bays for heat removal and that excessive sublimation of the ice bed will not occur because of warm air intrusion.

If an Ice Condenser Door is not capable of opening automatically, then ,

system function is seriously degraded and inmediate action must be taken to l restore the opening capability of the door. Not capable of opening automati- '

cally is defined as those conditions in which a door is physically blocked l from opening by installation of a blocking device or by obstruction from temporarily or permanently installed equipment. Impairment by ice, frost or i debris is considered to render the doors inoperable but capable of opening l automatically since these types of conditions will result in a slightly greater torque necessary to open the doors or a slight delay in door opening.

CATAWBA - UNIT 2 B 3/4 6-9 l

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1 l l Attachment 2c l

Revised Improved Technical Specifications Conversion l

Submittal Documentation for Catawba Unit 1 i

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1 1

Revised Current Technical Specifications Marked-up Pages l

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$gc, oNcet bro'n 3.6. /2.

E 8, [, CauTAlleEET 171TBt5 4 Lfts h 4 5

• m a ,

3 6. /2. M aam u - - ---- -

us

& J.(as/2. 4ZI:P The ice bed shell be efeMat1% i

{4. The stored ice hoe e beres concestretten of et l begge es sedite t reberate end a pH of 9.0 to 9.1 est 1000 ppn]

I

b. Flow channels the tcm condenser.

c. A senteus les tesperature of less thee er 1 to 27'F.

d. A tetel ice g

c fie.ce, ght of et lee @ f st s et a 994 level of olm4 see s. [ A., J 3 0,#J"6 APPLICABILITY: JIBE 51. 2. 3. end 4.

acTICE:

s

,477w A 6,wr hears se in as :tr usi :-fee_ibed ineserehle. testere the Ice bed to CPGAALE states within 40 l vnmin we next e meurs ans in uns =w..

g,y g 90tst withis the felleutes 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

Sunwrts e marr -- .a

@ 1he ice condenser shell be determined OPERAALE: l

/4 3./,./2._/ g At least once per 12 hears -.- ne. === i_ .

gass the serious ice bed tesperetste is less

. menino g

@ leastesteper9easth)s htAPVNM*k gg g,f,,fg 3 ,@ M1 emelyses adritet verify that et least slee reprotestative eagle,,s of etered see have e beres. sen.sent, .. to ret. tee o.f a.t 1eert.4

. me. e , e .

i m_

m ,,y.2 e m . h, e eis.ei .s,eeti.e .. .. _ fr st er ,

.- ieges.ef top [eer erstEne~ 'ofUstSU

. e i'MefeUIM Mc]4.pd

== w. ,

6wfn *< </q Ae=0

ann S .

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- .K 4 4carg gesAwr PAT @ kJ[7F Py e IJ2

i o hcshst sh 30/2 CQltTAIIBIGif SYSTDtt StatyrtttAmer aessfeemITS (cantiemedt UN'= E --. vuez is . . i ks., ga thickness et less than_er equal to 0.38 tech.Jf one low pass , m i,., ;. l__

' than m

mw =

er egne e e.Misuem loca, na .. t er cetative with a thickness of eroa le of 2e additt flew l pas fne the see bar she be visuell inspected. If '

'I addl anal flem passages are acceptab e, the serveil e ram may proceed censi the steele deficiency as (gs,and j table. Here than ese tricted flew passage ser is eviden 1 daaradattaa af he les -- ' -rr. /

e At leest once per 14 seeths bys

(

(f 3,4,/2.(.4L Wei leg a representative saeple of at least ce baskets and $

fring that each besbet contafes at leas Ibs of ice, al4 fee' had il Radial Anws 1, 2, ,6,8,and9(orfromthesame abfe[ of an adjacent bar if a beshet a designated row eaanet be eht med for

, weigh'Aa withi each ba contate less

• " N of ice,y.a Ifrepresestative any basket is feesd sample 20 additional l%

f -

nesteer roe seat bey shall be weighed. The telee everage metWit of i from the N addl 1 hastets the diserspant I bestet shal not be less thaa / bas t at a 954 levet ef)

N$$

M M* A 5 ***"d"""" ' h* "6d d'd **8.8Greev

*' 6"****

• as follows: Group 1.'" bars 1 threagh 2 - Bays 9 through.16, and Group -3 Saysfrem 11 through the sesple baskets Radle 24. Ine sinteum average ice weight of 1, 2, 4, 4, 8, and 9 fe eech gre w shall not be less s/ basket at a 954 level of A

confidsece.

g f The afstem total Jce condenser ice weight at a 95% level of g4 3.6./Z ,4. b confidence shall be calculated aslog all ice basket welehts .

M ~ ' ' durief this selghteg prograslane snati met be less than

<A E.6./t,4 U* V ' -- -' ' lg m/

$ _ least_ence per 40 er M rtman visually inspect 6 JAL '3,6./1, (, *

, _; - : _tuo fce baskets fres' each %._

___.._-a.enu.<-__._,

. _ . - _ _. ... _ , p ertrimental structurei eur, creeks, corressen er other dame,e o,-.._..._.,

Q m m +ko.I p

f~ 1 I Q '

epd A5 u

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.2.,33Of.cA CATJedBA tes!T 1 3/4 6 34 Amendment me.

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Ice Bed 3.6.12 l

l l SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.12.3 Verify by chemical analyses of at least 18 months l nine representative samples of stored ice:

l a. Boron concentration is 21800 ppm; and

b. pH is a 9.0 and s 9.5.

SR 3.6.12.4 Verify total weight of stored ice is 2 18 months 2,330,856 lb by: l

a. Weighing a representative sample of 2 144 ice baskets and verifying each basket contains a 1199 lb of ice; l and

b. Calculating total weight of stored ice, at a 95% confidence level, using all ice basket weights determined in SR 3.6.12.4.a.

l SR 3.6.12.5 Verify azimuthal distribution of ice at a 18 months 95% confidence level by subdividing weights, as determined by SR 3.6.12.4.a.

into the following groups:

i I

a. Group 1-bays 1 through 8;

b. Group 2-bays 9 through 16; and

c. Group 3-bays 17 through 24.

l The average ice weight of the sample '

l baskets in each group from radial rows 1, 2, 4, 6, 8, and 9 shall be 2 1199 lb. [

l l SR 3.6.12.6 Visually inspect, for detrimental 40 months L

structural wear, cracks, corrosion, or other damage, two ice baskets from each azimuthal group of bays. See SR 3.6.12.5.

l Catawba Unit 1 3.6-31 4/8/98 l I

Ice Bed B 3.6.12 B 3.6 CONTAINMENT SYSTEMS B 3.6.12 Ice Bed l BASES l

l BACKGROUND The ice bed consists of over 2,330',856 lb of ice stored in l

1944 baskets within the ice condenser. Its primary purpose j is to provide a large heat sink in the event of a release of energy from a Design Basis Accident (DBA) in containment.

l The ice would absorb energy and limit containment peak l pressure and temperature during the accident transient.

Limiting the pressure and temperature reduces the release of fission product radioactivity from containment to the environment in the event of a DBA.

The ice condenser is an annular compartment enclosing approximately 300* of the perimeter of the upper containment compartment, but penetrating the operating deck so that a

portion extends into the lower containment compartment. The i

lower portion has a series of hinged doors exposed to the atmosphere of the lower containment compartment, which, for normal unit operation, are designed to remain closed. At the top of the ice condenser fi another set of doors exposed to the atmosphere of the upper compartment, which also remain closed during normal unit operation. Intermediate j deck doors, located below the top deck doors, form the floor

of a plenum at the upper part of the ice condenser. These doors also remain closed during normal unit operation. The l upper plenum area is used to facilitate surveillance and l maintenance of the ice bed.

l The ice baskets held in the ice bed within the ice condenser l are arranged to promote heat transfer from steam to ice.

l This arrangement enhances the ice condenser's primary l

function of condensing steam and absorbing heat energy released to the containment during a DBA.

f In the event of a DBA, the ice condenser inlet doors I

(located below the operating deck) open due to the pressure I rise in the lower compartment. This allows air and steam to flow from the lower compartment into the ice condenser. The ,

, resulting pressure increase within the ice condenser causes i the intermediate deck doors and the top deck doors to open, '

which allows the air to flow out of the ice condenser into the upper compartment. Steam condensation within the ice I

condenser limits the pressure and temperature buildup in (continued) l Catawba Unit 1 B 3.6-74 4/8/98

[

Ice Bed l

B 3.6.12 l

BASES I

l SURVEILLANCE SR 3.6.12.4 (continued) l REQUIREMENTS

! and 9, respectively), where heat transfer into the ice condenser is most likely to influence melting or

! sublimation. Verifying the total weight of ice ensures that I

there is adequate ice to absorb the required amount of energy to mitigate the DBAs.

If a basket is found to contain < 1199 lb of ice, a j representative sample of 20 additional baskets from the same bay shall be weighed. The average weight of ice in these 21 baskets (the discrepant basket and the 20 additional baskets) shall be 21199 lb at a 95% confidence level. l Weighing 20 additional baskets from the same bay in the event a Surveillance reveals that a single basket contains

< 1199 lb ensures that no local zone exists that is grossly l deficient in ice. Such a zone could experience early melt out during a DBA transient, creating a path for steam to pass through the ice bed without being condensed. The Frequency of 18 months was based on ice storage tests and the allowance built into the required ice mass over and above the mass assumed in the safety analyses. Operating experience has verified that, with the 18 month Frequency, the weight requirements are maintained with no significant degradation between surveillances.

SR 3.6.12.5 This SR ensures that the azimuthal distribution of ice is reasonably uniform, by verifying that the average ice weight in each of three azimuthal groups of ice condenser bays is within the limit. The Frequency of 18 months was based on ice storage tests and the allowance built into the required ice mass over and above the mass assumed in the safety analyses. Operating experience has verified that, with the 18 month Frequency, the weight requirements are maintained with no significant degradation between surveillances.

SR 3.6.12.6

, This SR ensures that a representative sampling of accessible l portions of ice baskets, which are relatively thin walled, l

(continued)

Catawba Unit 1 B 3.6-81 4/8/98 l

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Ice Bed fire Londerder SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY l

SR 3.6. Verify total wei ht of stored ice is nths a u.ra .te s lb by: @ t

@9/f/6L a. Weighing a representative sa@ le of i

f a 144 ice baskets and verifying each l

/ basket contains a lb a' " - - h I

f b.

ed

/ 5 l M Calculating total weight of s IjJ') O,#4 ice, at a 95% confidence level, using

.ii ice basket we4ghts determined in SR 3.6. a.

1 i SR 3.6. Verify azimuthal distribution of ice at a months l 95% confidence level by subdividi l weights, as determined by SR 3.6. O a. W

into the following groups

C91

a. Group 1-bays 1 through 8:

b. Group 2-bays 9 through 16; and

c. Group 3-bays 17 through 24.

The average ice weight of the sample baskets in each roup from radial rows 1,

2. 4, 6, 8. and shall be h 4c, SR 3.6. Verify, by visual inspection, occtnulation 9 months

' of ice or frost on structural members conprising flow channels through the ice 1

condenser is s X0.38kinch thick. O I

( (continued)

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l LOC STS- 3.6-54 Rev 1. 04/07/95 Oebb

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Ice Bed (Ira fondoMed 2 I l

83.6.g 8 3.6 CONTA M ENT SYSTEMS k hQ ff"[,

8 3.6.

j Ice Bed (fertondens'erT3

[

• t Bas Ccnd)

{

e l BACKGROU2 l The ico bed consists of over u. m e n Ib of ice stored in baskets within the ice condenser. Its primary purpose is to i l'I44 provide a large heat sink in the event of a release of

! energy from a Design Basis Accident (DBA) in containment.

The ice would absorb energy and limit containment peak pressure and tenperature during the accident transient.

Limiting the pressure and temperature reduces the release of 1 fission product radioactivity from containment to the {

j environment in the event of a DBA.

l I l I The dce condenser is an annular compartment enclosing

approximately 300* of the perimeter of the upper containment compartment, but penetratin l portion extends into the lo+g4rthe operating compartment.

containment deck so that aThe lower portion has a series of hinged doors exposed to the l atmosphere of the lower containment compartment, which, for norsel unit operation, are designed to remain closed. At i the top of the ice condenser is another set of doors exposed to the atmosphere of the upper compartment, which also l

remain closed during normal unit operation. Intermediate

' deck doors. located below the top deck doors. form the floor of a plentsn at the upper part of the ice condenser. These doors also renain closed during nonnal unit operation. The upper pierun area is used to facilitate surveillance and ma1ntenance of the ice bed.

The ice baskets held in the ice bed within the ice condenser are arranged to promote heat transfer from steam to ice.

This arrangement enhances the ice ccndenser's primary l

' function of condensing steam and absorbin released to the containment during a DBA.g heat energy In the event of a DBA. the ice condenser inlet doors (located below the operating deck) open due to the pressure rise in the lower coapartment. This allows air and steam to flow from the lower compartment into the ice condenser. The resulting pressure increase within the ice condenser causes the intermediate deck doors and the top deck doors to open, which allows the air to flow out of the ice condenser into i

the upper conpartment. Steam condensation within the ice ,

i condenser limits the pressure and tenperature buildup in (continued)

• 00 STS-B 3.6-151 Rev 1, 04/07/95 Otfa..v be\.

M C ( $ N M' % EIVf M M TE.9 88

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1 l Ice Bed uce rondenser7 i B 3.6. I BASES (jij SURVEILLANCE SR 3.6. .1~ (continued)

REQUIREMENTS l temperature condition. This SR may be satisfied by use of the Ice Bed Taverature Monitoring Systen.

SR 3.6.

t

The weighing program is designed to obtain a representative

! sample of the ice baskets. The representative sanple shall l include 6 baskets from each of the 24 ice condenser bays and  !

! shall consist of one basket from radial rows 1, 2, 4, 6, 8 and 9.

l If no basket from a designated row can be obtained for weighing, a basket from the same row of an adjacent bay j shall be weighed, l

, l

! The rows chosen include the rows nearest the inside and l outside walls of the ice condenser (rows 1 and 2. and 8

! and 9, respectively), where heat transfer into the ice condenser is most likely to influence melting or " )

sublimation. Verifying the total weight of ice ensures th there is adequate ice to absorb the reau4

• amount o energy to mitigate the DBAs.

M T If a basket is found to contain < lb of ice, a representative sample of 20 additional baskets from the same bay shall be weighed. The average weight of ice in these 21 baskets (the disc nt basket and the 20 additional baskets) shall be a at fidence level. Q, Weighing 20 additional f bay in the event a Surveillance reveals that a single basket contains l 3

lb ensures that no local zone exists that is

, grossly deficient in ice. Such a zone could experience @ $

l m early melt out during a DBA transient, creating a path for II steam to pass through the ice bed without being condensed.  !

l Lq lGeT IIJ

! the allowance built into the required ice mass over andme trequency of1 m above the mass assuned in the safety analyses. Operating experience has verified that, with the month Frequency, the weight requirements are maintained with no significant degradation between surveillances.

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I (continued) l E STS B 3.6 156 Rev 1, 04/07/95 Obk i

l V uenc anwer zmo ${n

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Attachment 2d Revised Improved Technical specifications conversion i

1 Submittal Documentation for Catawba Unit 2 1

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$&&lroh 3.6.12.

3,(p CONTAlleeff SYSm6 dTf1Pfli7AiBBEnD ..

5,6,/2 ICE RfD l

/c.o 3,4 /l. CEEP The Ice bed shall be OPONLt I C meiW.- nu - . i.e. coecentratten of at less 1800 M l bene es sedim reberste end a pel of 9.8 to 9.5,

b. Flev rhammals reagh the ice condenser,

c. A maziam i temperaten of less than er I to 27*T, l

A total i melght of at leasM ' .+ . eu t-i .a g

d.

e i n. A 7 Nj Wd j

APPLtcAsttfTY: 8CDES 1, 2, 3, and 4.

l acTlen l

,9ctm/ 4 'stra uni >[ce had tasserable, resten the ice bed to CPEMstt states within 48 _

h ni.,. ...aesst - m . .t.no .e . . ._ m e .. - - -

g soldFwithis the fellowing 38 hours4.398148e-4 days <br />0.0106 hours <br />6.283069e-5 weeks <br />1.4459e-5 months <br />.

l suevrnusscr a-,i_ =

• l d'Mb the ice eendenser shall be deteraleed OPEMBLE:

g B. C. /2. . / C At least

- --- - -i rme y,/4 l np . ,,, enee 7 in,gser,1,2 heers av taie smuteses ice- -bed

= =temperaten is less a

'h an er egust to 27*F.

@ (KFleast once per 9 aesths Ma. d' !I h

$4. 5. 4,. /2.3 $ Mhestcal analyses unich verify that at least eine representative semples of stared ice have a bores concentration of at least late pre - - - - = and a pet of 9.8 to 9.5 M/ '

and h Verifying by a VIsmal lespecties,mr at i men a n -..

M 3 4 ./2 A y_ - - ..- -_- ==laties of frest er ice, t

/Wesun" Wesert f e .r.UL"*"ET I"M .i W 7 1%ckd-wiemberp i

W re4eny !/pt4/

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dv4 erie /.* 6 ire =y4 t%e tee

<:o.ede><Ser aE.

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carm .Mn2 mn - e. K l t

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[qc. /o[2-

• lxAWCF NmENfMFA/T DATO [8fg

$ff &n.kto'n S.bs k CONrAIMIT $fSTDIS SuRvf1LLANE Rfout99 effs (cantiamedt a .- n - -- -- u n none h Tflew a thickness of less_

er ogsel to 0.38 inch)tfer ice $ _

cb y u i _ _s of greater thee

~ ^^

a i .38 inde. a representat samle of 20 aWittene flow the same bay shall seetly inspected. If .Af addit flew passages ass f acceptable, the serveill I proceed considerlag slagle deficiency as and

. More than ene isst cted flew passage ser hay 8 evi I deeradetion of ice candenser. e 6 At least once per 18 months by: l)N g y g g lie lag a repre ce baskets and 1R fri., m t aa b

.sentative. '

sample of at hs leastco.ui.satiJea of ice.

j

f. u. i.+

- W;;:2:  ;',h:;;'" lCli C'T".sil"t.ted Radial Ases 1 2, 4 6 ,andg(orfreethesamerowof .f e.e heat a(Jac if a basket f a i ed row cannot be obtatead r g4 se say. r any hastet is foung se la isss M Sr hwitate ( ice, a representative sample of te itional  % ,

I s- essas r run same hay shall be wei The sia average N shel f *N ^25 N ofJ W he

- ,n -

a lW The ice eendomser shall aise he hdtaded inte 3 of hasant.-

$4. M, /2 5" as fellems: stesy 1. hays 1 through 8. Group 2 9 th k, and . Says 17 thrwegh 24. The sistain average ice wei of the e baskets from Rati 1, 2 4, 6, 4. and 9 le each shall set he less M at a 9M level of l4

\\94 i h aleissa total ice eendomser ies weight at a 90% level of ft, J./f, /2 6 h coefiesace shall be calculated ustog all ice basket weights

, h8 mad deries this weighias preeremrams snau est me less than $r.

$A.'5.fo./2.'f_ Ge'7*" P =

, @ [At least,ence per de visually laspectrugrumm M/2. G J 3 g 7 _ *-- %---- .t" ic' ****'t8 f= "ch S _

decriannui serwturei wear, ch.cis, eermt= or echer dames.

- ---- .... - ,.. .. .... u .r - . . _ _ _ _ _ . ,

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Ice Bed i . .

-3.6.12 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY l

, SR 3.6.12.3 Verify by chemical analyses of at least 18 months nine representative samples of stored ice:

a. Boron concentration is 2 1800 ppm; and

! b. pH is a 9.0 and s 9.5.

SR 3.6.12.4 Verify total weight of stored ice is a 18 months 2,330,856 lb by: l l a. Weighing a representative sample of a 144 ice baskets and verifying each basket contains 21199 lb of ice; l and

b. Calculating total weight of stored ice, at a 95% confidence level, using l all ice basket weights determined in SR 3.6.12.4.a.

l SR 3.6.12.5 Verify azimuthal distribution of ice at < 18 months 95% confidence level by subdividing weights, as determined by SR 3.6.12.4.a into the following groups:

a. Group 1-bays 1 through 8;

b. Group 2-bays 9 through 16; and

c. Group 3-bays 17 through 24.

l The average ice weight of the sample baskets in each group from radial rows 1, 2, 4, 6, 8, and 9 shall be > 1199 lb. l l

l SR 3.6.12.6 Visually inspect, for detrimental 40 months structural wear, cracks, corrosion, or other damage, two ice baskets from each azimuthal group of bays. See SR 3.6.12.5.

Catawba Unit 2 3.6-31 4/8/98 l l

i Ice Bed

=

• B 3.6.12 8 3.6 CONTAINMENT SYSTEMS l B 3.6.12 Ice Bed l

l BACKGROUND The ice bed consists of over 2,330,856 lb of ice stored in 1944 baskets within the ice condenser. Its primary purpose is to provide a large heat sink in the event of a release of l energy from a Design Basis Accident (DBA) in containment.

The ice would absorb energy and limit containment peak pressure and temperature during the accident transient.

Limiting the pressure and temperature reduces the release of fission product radioactivity from containment to the 4 environment in the event of a DBA. l The ice condenser is an annular compartment enclosing approximately 300* of the perimeter of the upper containment l compartment, but penetrating the operating deck so that a i portion extends into the lower containment compartment. The lower portion has a series of hinged doors exposed to the atmosphere of the lower containment compartment, which, for normal unit operation, are designed to remain closed. At the top of the ice condenser is another set of doors exposed to the atmosphere of the upper compartment, which also remain closed during normal unit operation. Intermediate  ;

ceck doors, located below the top deck doors, form the floor j of a plenum at the upper part of the ice condenser. These doors also remain closed during normal unit operation. The l upper plenum area is used to facilitate surveillance and j maintenance of the ice bed.

! The ice baskets held in the ice bed within the ice condenser l

! are arranged to promote heat transfer from steam to ice. I l This arrangement enhances the ice condenser's primary l

function of condensing steam and absorbing heat energy l released to the containment during a DBA.

J l

In the event of a DBA, the ice condenser inlet doors )

(located below the operating deck) open due to the pressure l rise in the lower compartment. This allows air and steam to i flow from the lower compartment into the ice condenser. The l resulting pressure increase within the ice condenser causes the intermediate deck doors and the top deck doors to open, l which allows the air to flow out of the ice condenser into l the upper compartment. Steam condensation within the ice condenser limits the pressure and temperature buildup in (continued) l Catawba Unit 2 B 3.6-74 4/8/98 I

t

Ice Bed

=

• B 3.6.12 BASES i

SURVEILLANCE SR 3.6.12.4 (continued)

REQUIREMENTS and 9, respectively), where heat transfer into the ice condenser is most likely to influence melting or sublimation. Verifying the total weight of ice ensures that there is adequate ice to absorb the required amount of energy to mitigate the DBAs.

If a basket is found to contain < 1199 lb of ice, a l representative sample of 20 additional baskets from the same bay shall be weighed. The average weight of ice in these 21 baskets (the discrepant basket and the 20 additional baskets) shall be :t 1199 lb at a 95% confidence level. l Weighing 20 additional baskets from the same bay in the event a Surveillance reveals that a single basket contains

< 1199 lb ensures that no local zone exists that is grossly l deficient in ice. Such a zone could experience early melt out during a DBA transient, creating a path for steam to pass through the ice bed without being condensed. The Frequency of 18 months was based on ice storage tests and i the allowance built into the required ice mass over and above the mass assumed in the safety analyses. Operating i experience has verified that, with the 18 month Frequency, the weight requirements are maintained with no significant  !

degradation between surveillances.

SR 3.6.12.5 l

This SR ensures that the azimuthal distribution of ice is reasonably uniform, by verifying that the average ice weight l in each of three azimuthal groups of ice condenser bays is within the limit. The Frequency of 18 months was based on ice storage tests and the allowance built into the required ice mass over and above the mass assumed in the safety analyses. Operating experience has verified that, with the 18 month Frequency, the weight requirements are maintained with no significant degradation between surveillances.

SR 3.6.12.6 This SR ensures that a representative sampling of accessible portions of ice baskets, which are relatively thin walled, (continued)

Catawba Unit 2 B 3.6-81 4/8/98 l l

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I tachment 3 D**cription of PrODosed Chan 88 and Technical Justification i

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Description of Proposed Changes The primary function of the ice condenser is the absorption j of thermal energy released abruptly in the event of a loss {

of coolant accident or steam line break, thereby limiting the initial peak pressure in the containment. A secondary function of the ice condenser is the further absorption of energy after the initial accident, causing the containment pressure to be reduced to and held at a lower level for a period of time. The ice condenser is contained in the annulus formed by the contain:aent vessel wall and the crane wall circumferentially over a 300 degree arc. The ice

)

condenser is a passive device, requiring only the maintenance of the ice inventory in the ice bed.

Technical Specification 3/4.6.5 delineates the requirements for the ice condenser. This specification requires a total ice weight of at least 2,475,252 pounds. Since there are j 1944 ice baskets associated with the ice condenser in each unit, this translates into a requirement of 1273 pounds per basket. The Bases for the ice condenser Technical Specification stipulates that in the event that observed sublimation rates are equal to or lower than design predictions after three years of operation, the minimum ice basket weight may be adjusted downward.

Limiting Condition for Operation 3.6.5.1 is being modified to decrease the total ice weight requirement to 2,330,856 pounds. Surveillance Requirement 4.6.5.1c is being modified to require a minimum ice weight of 1199 pounds per basket.

Also, Technical Specification Bases section 3/4.6.5.1 (Ice Bed) is being modified consistent with the above proposed modifications. In addition, the 15% conservative allowance reference in the Bases section is being modified to a 90 pound conservative allowance. The 90 pound value represents a conservative allowance of 8.2% of the safety margin based on the minimum required ice weight of 1199 pounds per basket. Also, the clarifying words "during the fuel cycle" have been added to the Bases discussion. Finally, the last sentence in the Bases discussion pertaining to adjusting minimum ice basket weight is being deleted pending approval of this license amandment request.

As indicated in the cover letter for this amendment request, commensurate changes are also being proposed for all relevant documentation associated with the May 27, 1997 Improved Technical Specifications conversion submittal for Catawba. These changes are being supplied to facilitate the NRC review of the conversion submittal.

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l Technical Justification The current Technical Specification requirement of 1273 pounds of ice per basket is composed of three components:

i (1) the basic safety margin required minimum quantity of ice (1097 pounds), (2) an allowance of 15% of the safety margin number to account for euilimation during the fuel cycle (164 pounds), and (3) an additional 1.1% of the safety margin number to account for ice basket weighing errors (12 pounds). (This proposed license amendment does not impact the safety margin ice requirement or any safety or i containment analyses. It only impacts the amount of ice required to account for sublimation.)

The Ice Condenser Data Management System (ICEMAN) contains approximately 10,000 ice basket weight records taken over the life of the plant. Individual ice basket average sublimation rate data as contained in ICEMAN was utilized to determine an overall average observed sublimation rate for each ice condenser at Catawba. The average sublimation rate, which is quantified in units of pounds of ice loss per day, was multiplied by the current interval between ice basket weighing (18 months) to determine the average pounds of ice loss per basket for each Catawba unit. These values were then multiplied by a safety factor of 2 to determine a revised appropriate allowance for sublimation. It is assumed that the ice loss for each ice condenser is similar; therefore, the more limiting of the two ice condenser values was utilized for Catawba as the revised appropriate ,

allowance for sublimation.

Major inputs and assumptions into the sublimation calculation included the following:

1. ICEMAN has been validated over time to correctly predict

, ice basket weight. During the Unit 1 End of Cycle 10 l Refueling Outage, 1437 baskets were weighed. ICEMAN correctly predicted basket weights within a +/- 10 pound band 284 times and within a +/- 40 pound band 638 times.

Historically, ICEMAN projects weights lower than are  !

actually observed. The remaining baskets included 257 which were stuck. 191 baskets were found to be greater l than 40 pounds above the projected weight. Only 67 baskets had weights below the 40 pound band. These are typical orcjection results and they validate the conservative nature of ICEMAN calculated average sublimation rates.

2. Only positive sublimation rates were considered in the calculation of average sublimation rate. There are a l

number of ice baskets at Catawba which, over the course l

of each fuel cycle, actually gain weight. These are represented within ICEMAN as baskets with negative l sublimation rates. These baskets are typically located close to the annulus wall which is away from the heat '

l released by the reactor, pressurizer, and steam l generators. These baskets typically grow frost along their outer surfaces due to their relatively cold l temperature within the ice bed. Additionally, there are  !

baskets located slightly closer to the crane wall which i remain in a steady state condition with respect to '

sublimation. These baskets have a sublimation rate of zero within ICEMAN. For conservatism, the calculation of average sublimation rate did not include these baskets.

Finally, there are a few baskets in each unit which have had a continuous history of being frozen in place. For these baskets, ICEMAN sets the sublimation rate to zero. l In the absence of any sublimation data, these baskets are replenished each refueling outage to ensure each contains a full load of ice for the fuel cycle. These baskets l were not included in the calculation.

3. A safety factor of 2 was applied in the calculation.

ICEMAN contains a vast quantity of weight information and it uses this to accurately calculate sublimation rates for each individual ice basket. In order to provide additional assurance that a sufficient allowance has been made for ice basket sublimation and to ensure that fuel cycle extensions will not result in ice mass dropping below the required safety margin value, a safety facter of 2 was applied.

4. Conservatisms within the calculation adequately bound the surveillance requirement's 25% grace period.

Surveillance Requirement 4.6.5.lc is based on an 18 month I interval with a grace period of 25%. Based on only utilizing positive sublimation rates c.nd the application of the safety factor of 2, calculations show the additional ice loss which would occur if the 25% grace period were utilized would not result in ice mass dropping below minimum requirements.

The average of all positive sublimation rates for the Unit 1 and 2 ice condensers is 0.0810 pounds per day and 0.0728 l pounds per day, respectively. The calculation of an I appropriate sublimation allowance is expressed by the following equation:

Allowance = (Sublimation Rate) x (Days in Fuel Cycle) x (Safety Factor) l 1

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i For an 18 month (550 day) fuel cycle, the sublimation allowance for Units 1 and 2 is therefore 89.10 pounds per basket and 80.08 pounds per basket, respectively. For the station, the revised allowance for sublimation was chosen as 90 pounds per basket based on the above determination.

This technical justification has shown that the allowance for sublimation in the Catawba Unit 1 and 2 ice condensers I can be reduced from 164 pounds to 90 pounds in accordance '

with the Technical Specifications Bases to more closely represent observed sublimation rates at Catawba. I Appropriate conservatism is still maintained to ensure ice condenser operability.

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l Attachment 4 l No Significant Hazards Consideration Determination I 1

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No Significant Hazards Consideration Determination l

l The following discussion is a summary of the evaluation of l

the changes contained in this proposed amendment against the j 10 CFR 50.92(c) requirements to demonstrate that all three 1 standards for_no significant hazards consideration are satisfied. A no significant hazards consideration is indicated if operation of the facility in accordance with the proposed amendment would not:

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1. Involve a significant increase in the probability'or i consequences of an accident previously evaluated, or l

2. Create the possibility of a new or different kind of l

accident from any accident previously evaluated, or '

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

First Standard i

Implementation of this amendment would not involve a significant increase in the probability or consequences of ,

an accident previously evaluated. The ice condenser is not ;

an accident initiating system; it is an accident mitigating system. Therefore, reducing the required ice weight in accordance with this proposed amendment cannot impact accident initiating probabilities. The technical justification associated with this proposed amendment shows that the ice condenser will remain fully capable of performing its design accident mitigation function following such conditions. Therefore, no accident consequences will be impacted, j Second Standard i

Implementation of this amendment would not create the possibility of a new or different kind of accident from any

accident previously evaluated. As noted previously, the ice l condenser is not an accident initiating system. Reducing the required ice weight in accordance with this proposed i amendment will not impact any plant systems that are i accident initiators. No other modifications are being l proposed to the plant which would result in the creation of l new accident mechanisms. Also, no changes are being made to i the way in which the plant is operated, so no new failure mechanisms will be initiated.

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. - o Third Standard Implementation of this amendment would not involve a significant reduction in a margin of safety. Margin of safety is related to the confidence in the ability of the fission product barriers to perform their design functions during and following an accident situation. These barriers i include the fuel cladding, the reactor coolant system, and l the containment system. The performance of the fuel I cladding and the reactor coolant system will not be impacted by implementation of this proposed amendment. The technical justification associated with this proposed amendment shows that the containment will remain fully capable of performing its design function, as the ice condenser will continue to meet all design acceptance criteria. Therefore, no safety margin will be signi cantly impacted.

Based upon the preceding analysis, Duke has concluded that the proposed amendment does not involve a significant hazards consideration.

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i Attachment 5 Environmental Analysis l l 1

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Environmental ~ Analysis Pursuant to 10 CFR 51.22(b), an evaluation of this license amendment request has been performed to determine whether or not it meets the criteria for categorical exclusion set

- forth in 10 CFR 51.22 (c)'-(9) of the regulations.

This amendment to the Catawba Unit 1 and 2 Technical

-Specifications allows for a reduction in the. required ice condenser stored ice requirements based on calculations of ice sublimation rates using computer methodology.

Implementation of this amendment will have no adverse impact j upon the Catawba units; neither will it contribute to any l additional quantity or type of effluent being available for

! adverse environmental impact or personnel exposure.

l It has been determined there is:

1. No significant hazards consideration, l 2. No significant change in the types, or significant increase in the amounts, of any effluents that may be released offsite, and l 3. No significant increase in individual or cumulative L occupational radiation exposures involved.

l l .Therefore, this mmendment to the Catawba Technical I Specifications meets the criteria of 10 CFR Sl.22 (c) (9) for

[ categorical exclusion from an environmental impact l statement.

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