ML20065T436

Proposed Tech Spec 3/4.6.5.1,increasing Surveillance Interval for Weighing Ice from 9 to 18 Months

ML20065T436
Person / Time
Site:	Catawba
Issue date:	12/21/1990
From:	DUKE POWER CO.
To:
Shared Package
ML20065T431	List: ML20065T429 ML20065T436
References
NUDOCS 9012280122
Download: ML20065T436 (13)

Text

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ATTACIMENT 1 Proposed Technical Specification Changes i.

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CONTAINMENT SYSTEMS 3/4.B.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=2,350,552 ounds 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 nours 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 OPERA 8LE:

-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 t I) (mSERT INDicATEL PAPA &PAPH ON NGE 3N 6 Weighing a representative sample of at least 144 ice baskets

)- lg73 and verifying that each basket contains at least 4EMNes.of ice. The representative sample shall include six baskets from the 24 ice condenser ba s and shall be constituted of C- Ar LE4ST ONc6 PER lT WNTHs By:

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CATAWBA - UN1.'5 1 & 2- 3/4 6-41

. CONTAINMENT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

@i one basket each from. Radial Rows 1, 2, 4, 6, 8, and 9 (or from W

the- same row of an adjacent bay if a basket from a designated Q cr row cannot be obtained for weighing) within each bay. If any F basket is found to contain less than -lH&~ pounds of ice, a WI3 representative sample of 20 additional baskets from the same de bay shall be weighed. The minimum average weight of ice from P the 20 additional baskets and the-discrepant basket shall not be less than p g / basket at a 95% level of confidence.

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The ice condenser sha also be subdivided into 3 groups of Q baskets, as follows: Group 1 - Bays 1 through-8, Group 2 -

Bays 9 through 16, and Group 3 - Bays 17 through 24 The

f. minim a average ice weight of the sample baskets from Radial

~. 1, 2, 4, 6, 8, and 9 in each group shall not be less than W -1M

)a73 ounds/ basket at a 95% level of conficence.

g Y e minimum total ice condenser ice weight at a 95% level of confidence shall be calculated using all ice basket weights date ppgME hing program and shall not be less tha {,g,55 pounds /-ane.

24f VerilyY7a visual inspection of at least tm flow passages 4 per ice condenser bay, that the accumulation of frost or ice on flow passages between ice baskets, past lattice frames, .nrough 2 the top deck floor grating, or past the lower inlet plenum support 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 acceptaDie, the surveillance program may proceed considering the single defi-ciency'as unique and acceptable. More than one restricted flow passage -per bay is evidence of abnormal degradation of the ice condenser.

cl.[. 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 detri-mental structural wear, cracks, corrosion or other damage. The ice baskets shall be raised at least 12 feet for this inspection.

CATAWBA - UNITS 1 & 2 3/4 6-42

4 CONTAfNMENT 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.

314_.6.5.1 ICE BE0 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 saf nal ses.

12 7 The minimum weight figure of on 3 of ice per basket contains w% \5 /o E conservative allowance for ice loss through sublimation.Wer 4 2 P te c.

The minimum total weight [

} M-h4 ghee pounds of y 53,552 4han-assumed-foMhe-ice-condenser-des of ice also contains 6n additional # conservative 4n, allowanc n to account for systematic error in the weighing instruments. In the event that 7

@ observed 3 years of tablimation rates operation, the are equal minimum to or lower ice baskets weightthan maydesign predictions be adftasted after downward.

& :dditi:., th: M:r -ef--ice b::ket: requiw + t be weighee=each o = tr.: ry be--eeduced-af-teWears-of-operat4on-14-such-e-reductrion 1: Ouppoeted4y-

.-obsamd subl %2 tion data.

3/4.6.5.2 ICE BE0 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 i:e bed heat removal capacity will be retained within the specified time

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3/4.6.5.3 ICE CONDENSER 000RS 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 Condensar Door is not capable of opening automatically then system function is; seriously degraded and immediate action must be taken to restore the opeaing carability of the doce. Not capaole of opening automati-cally is defined as those conditions in which a door is physically blocked from opening by installation of a blocking jevice or by obstruction from temporarily or permanently installed equipment. Impairment by ice, frost or debris is con-sidered 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 - UNITS 1 & 2 B 3/4 6-5

l ATTACHMENT 2 Justification and Safety Analysis Introduction The requested changes to Technical Specification (TS) 3/4.6.5.1 change the frequency of ice basket weighing from at 1 cast once por 9 months to at least once per 18 months. To ensure the minimum ice weight does not fall below that required by the safety analysis, the required TS ice bed weight (total ice bed and per ice basket) of the Ice Condenser will be increased.

The TS Bases section has been revised to reflect the above changes and to correct an existina error.

Background

As discussed in FSAR Section 6.2.1.1.1, the Ice Condenser is designed to limit the Containment pressure below the design pressure for all reactor coolant pipe break sizes.up to and including a double-ended severance.

The Ice Condenser also surves as a Containment air purification and cleanup system by absorbing molecular iodine from the containment atmosphere following a LOCA as described in FSAR Section 6.5.4. The required boron concentration (at-least 1800 ppa) and pH (9.0 - 9.5) of the stored ice is not affected by this TS change request. Therefore, the air purificatio aspects of the Ice Condenser remain. unchanged by this submittal.

The Ice Condenser is subdivided into 24 bays which contain 1944 ice baskats that are 12 inches-in diameter and 48 feet long. Each bay consists of 9 columns and 9 rows of ice baskets. The ice baskets function to promote heat transfer from the steam to the ice during and following a LOCA or steam line break in the Containment by ensuring the ice inventory is evenly distributed, contains sufficient heat removal capability, and is maintained in the appropriate geometry. ' Refer to FSAR Figure 6.7-1 for an isometric drawing of the Ice Condenser. The Ice Condenser is also administrative 1y subdivided into 3 groups of baskets for the purpose of icoEweighing. Group 1 consists of bays 1 through 8, Group 2 consists of bays-9 through 16, and Group 3 consists of bays 17 through 24.

-Technical Specification 3/4.6.5.1 specifies that the ice bed shall be operable with a total-ice weight of at least 2,368,652 pounds at a 95%

level of confidence with 1944 ice baskets. This is tne minimum amount of

' ice to be maintained in the Ice Condenser to control the anticipated heat load-during a-large scale LOCA. These conditions are applicable in Modes l'through 4. The TS action statement specifies that 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 the Unit must 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 Shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

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P6r FSAR Section'6.2.1.'.3.1, Loss of Coolant Accident, the " Peak

, Containment Pressure Transient" analysis assumes 2,132,000 pounds of ice initially in the Ice Condenser. A_ 10% conservative allowance for ice bed loss through sublimation is added to the above value as well as a 1.1%

conservative allowance to account for errors in the weighing instruments (Note that the current TS 3/4.6.5.1 Bases Section incorrectly states that the 1. :trument error is 1% than the actual value of 1.1%). These connet vative allowances are intended to ensure that the actual total ice weight remains above the value assumed in the FSAR analysis for the duration of the fuel cycle. Thus, the-TS minimum ice bed weight is calculated as 2,132,000 lbs. plus 11.1% (236,652 lbs.) for a total weight of 2,368,652 lbs. This value, when divided by the number of ice baskets (1944) determines the minimum average TS ice weight per basket as 1218 pounds.

TS Surveillance Requirement 4.6.5.1 currently requires that at least once per 9 months a representative sample of at least 144 ice basketa be weighed to verify with a 957. Level of Confidence that the minimum average weight for Bay and Row group ice baskets .is 1218 3bs. with a minimum total ice bed weight of 2,368,652 lbs._ If any Lasket is found to contain less than 1218 lbs. of ice, a representative sample of 20 additio..a1 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 1218 lbs. por basket at a 95% confidence level. The basis for this requirement reccgnizes that sublimation will occur during Unit operation resulting in lowered ice weights (some possibly below 1218 lbs.), aan it is not meant to impose this weight limit for all baskets at all times as long as the total ice weight can be shown not to be less than 2,368,652 lbs. at the-surveillance period.

As noted above, the TS Limiting Condition for Operation total ice weight (2,368,652 lbs.) is to ensure the actual ice bed weight remains above the value assumed.in the FSAR analysis for the duration of the fuel cycle.

(2,132,000.lbs.). Therefore, the TS surveillance requirements were written to ensure that the actual minimum average ice weight for any statistical sub group always remains above 1097 lbs, per basket (2,132,000 lbs. divided by 1944 baskets). The 1097 lbs, per basket required by the safety analysis plus a 1.1% weighing uncertainty factor equals 1109 lbs.

per basket and is referred to as the design basis weight for each ice basket. As long as the measured minimum average ice weight per basket remains above 1109 lbs, from one refueling outage to the next, an adequate safety margin is maintained.

Technical Justif1 cation and Safety Analysis To provide _ justification for a TS change to decrease the frequency of the ice basket weighing program from 9 months to 18 months, past operating experience at Catawba was analyzed to evaluate ice basket sublimation rates._ The current TS total.-ice weight and minimum average ice basket ice weights are based upon a 10% per nine month sublimation rate as discussed in the " Background" section of this attachment. Operating experience at

Catawba has shown that Ice Condenser sublimation rates are much less than this value.

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l The average ice _ basket sublimation rates from previous years are tabulated 1 below for_ Unit 1 and Unit _2. The average pounds per year sublimation R rates are based upon-actual weighing data taken during the TS surveillance periods and include data _for all 1944 ice baskets. An average " percent i per year" sublimation rate was-then calculated based upon_the_ average pounds per year sublimation rate applied to the existing TS minimum

-average ice basket ice weight of 1218 pounds.- Actual sublimation rate percentages would be lower than those calculated because_the ice baskets are always loaded heavier than the minimum TS requirement. As shown in the tables, the worst case average sublimation rate b.ased upon all Ice Condenser ice baskets on a per year basis is less th.a 5% per year.

Average Ice Basket Sublimation Rates Based Upon All Ice Baskets Unit 1 Unit 2 Sublimation Rate Sublimation Rate

-Year (1bs/yr) (%/yr) Year (Ibs/yr) (%/yr) 1985 59 4.84 - - -

1986 47 3.86 - - -

1987 38 3.12 19t? 59 4.84 1988 29 2.38 1968 39 3.20-1989 39 3.20 1989 39 3.20 1990 29 2.38 1990 33 2.71 In-addition to analyzing tns 1otal avetage. ice basket sublimation rates, the average sublimation rate and the average ice basket weight were determined from the worst case baskets (Row 9) for all 24 Bays as shown in Enclosure 1. Unit 1 data is tabulated on page-1 of Enclosure 1, and Unit 2 data is tabulated on par,o 2. Row 9 was chosen because it-is.the row adjacent to the crane wall U losest to the reactor) and therefore experiences the highest sublimation rates in-the Ice Condenser. The ave. age sublimation rate for bo*h the Unit 1 and Unit 2,. Row 9 baskets is .

also less than 5% por year.

To account for increased sublimation between surveillance periods in the proposed TS change, the total required ice bed weight as well as the '

minimum average ice basket weight will be-increased. To calculate the.new TS total ice weight a sublimation rate of 15% is assumed. The 15%

sublimation rate is considered to be very conservative based upon the measured sublimation ratee at-Jatawba being consistently lower than 5% per-year as discussed above. Accounting for the-increased sublimation rate, the new TS total ice bed weight for an 18 month surveillance frequency is 2,475,252 pounds. This is derived by adding to-the safety analysis ice

. weight (2 ;L TOO.lbs.) a quantity of_ ice for an estimated sublimation rate of IL 9,800 lbs.) and adding 1.1% more ice.to account for weighing.orru (23,452_lbs.). Dividing this value by the total' number of Lee baskets (1944) yields the new TS minimum-average-ice basket weight of 1273 pounds per basket.

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- P'revious surveillance results were compared to the. proposed TS limits for row group _and total ice weight to demonstrate that Catawba would meet ,

these new restrictions upon issuance of thn requested license amendment.

4 Total 2ce weight calculations from the previous three surveillances on Unit 1 and Unit 2 indicate that total ice weight exceeded the proposed 1-imit of 2,475,252- pounds. In addition, the minimum average ice weight of

, the row group sampling required by the TS surveillance execeded the 1273 pounds per basket. Therefore, based upon the most recent TS surveillance data, Catawba vill be in compliance with the proposed TS upon issuance by the NRC staff.

To demonstrate that the design basis ice weight will not be compromised, the Row 9 average ice basket ice weights from the last weighing surveillance were projected for an 18 month period. Rcw 9 basketh experience the greatest sublimation and are therefore bounding for the remainder of the Ice Condenser ice baskets. The Row 9 average ice weights were projected for an 18 month period using the actual Row 9 sublimation rates and also using an assumed sublimation rate of 15%. These projections are tabulated in Enclosure 1 for both Units. These projected weights were compared to the design basis weight of 1109 pounds per basket

-to ensure that sublimation over an 18 month interval would not challenge the design basis minimum Ice Condenser weight. The design basis weight for each basket is calculated by dividing the total amount of ice assumed in the 1.0CA safety analysis (2,132,000 lbs.) by the number of ice baskets (1944) and adding an additional amount of ice fer measurement errors (1.1%). This analysis showed that the projected average ice weight of the Row 9 ice baskets remained above the design basis value over an 18 month period whether using actual sublimation rate data or an assumed 15%

sublimation rate.

As discussed above, the existing total ice weight of both Unit 1 and 2 Ice Condensers is sufficient to account for sublimation that will occur over the remainder of an 18 month period. The next projected refueling outage

-date for Unit.1 is March. 15, 1991 and October 22, 1991 for Unit 2. These projected outage dates correspond to an 11 month period for Unit 1 (300 EFPD core) and a.13 month period-for Unit 2 (350 EFPD core). Therefore, the length of time between TS surveillances (outage-to-outage) for the existing quantity of lee in-the Ice Condenser will.be less tran the 18 months specified in the proposed TS. This results in additional conservatism,-ensuring the design basis ice weight will not be compromised based-upon the TS surveillance being extended from 9 months to the next refueling outage on each Unit.

Conclusion Operating experience at Catawba has shown that the lec Condenser sublimation rates are much less than the 10% per 9 months as currently accounted for in the Ice Condenser Technical Specification 3/4.6.5.1.

Using actual sublimation: data and current ice basket weights,-the average weight of each Bay's Row ~9-ice baskets have been projected over an 18 month period. The Row 9 ice baskets experience the most sublimation and therefore bound the remaining baskets in the Ice Condenser. The projected average Row 9 ice basket weights all-exceed the minimum average ice weight assumed in the safety analysis.-

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.To: ensure the minimum average ice weight for the duration of the new  ;

y surveillance interval is not compromised, the TS required minimum total ice weight as.well as the individual ice basket weight has been increased.

Analysis of past ice weighing data indicates that the total ice weight and the minimum average ice weight per basket for the row group analysis required by TSs has always exceeded the increased ice weight limits of the proposed Technical Specification.

~ It can be concluded that since the required weight of ice as assumed in the 1.0CA Peak Containment Pressure Transient analysis, which is the design basis for the Ice Condenser, will be present at the end of the 18 month cycle, the ice weighing interval can bn extended to 18 months.

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Enclosure.1

.t Page 1 of-2 Ice Condenser Sublimation Data Unit 1 Projected- Projected 18 Month 18 Honth Average. Average Average Weight Using Weight Sublimation - Sublimation Row 9 Measured Using 15%

Rate, Row 9 Rate, Row 9 Weight Sublimation Sublimation Bay # (1bs/yr)) (%/yr)

(1bs)2 (1bs)3 (1bs)3 1 144 9.89 1456 1240 1238 2 73 5.11 1430 1321 1216 3' 65 4.39 1480 1383 1258 4 61 .4.22 1447 1355 1230 5 98 6.58' 1489 1341 1266 6 60 3.89 1542 1452 1311 7 114 7.31 1560 1389 l'26 ,

8- 94 6.21 1515 1374 1288 9 107 7.10 1508 1347 1282 10 67 4.41 1521 1421 1293 11 53 3.66 1449 1370 1232 12 20 1.35 1487 1457 1264 13 51 3.40 1499 1423 1274

-14 41 2.67 1538 1477 1255

.15 75 4.79 1567 1455 1332 16 30 '2.01 1492 1447 1268 17 25 1.62 1541 1504 1310 18 46 2.98 1542 1473 1311 19 71' 4.-75 1495 1389 1271 20 88 5.63 1562 1474 1328 21 44 .2.79 1577 1511 1340 l 22 47 3.06 1538 1468 1307 23 41 2.61 1573 1512 1337 24 140 9.42' 1486 1276 1263 Total Average 1 Sublimation Rate- ~

for Row 9 Baskets = 4.58 %/yr Notes:- 1. The sublimation rates are calculated on an annual basis (versus'a 9 month rate) because the' majority of the data was

-recorded during refueling outages that fell on a 12 month cycle.

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2. Actual-data from-last'TS ice weighing-surveillance.

3. Projected' minimum average ice weights all exceed design basis l

limit of 1109 pounds. j 1

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Ice Condenser Sublimation Data Unit 2 Projected Projected 18 Month 18 Month Average Average Average Weight Using Weight Sub11matlon Sublimation Row 9- Measured Using 15%

Rate, Row 9 Rate. Row 9 Wolght Sublimation Sublimation Bay II (1bs/>e)g (%/yr)

(1bs)2 (1bs)3 (Ibs)3 1 78 5.21 1496 1379 1272 2 62 4.35 1425 1332 1211

'3 29 2.04 1422 1379 1209 4 110 7.43 1480 1315 1258 5 103 7.15 1440 1286 1224 6 93 6.20 1499 1406 1274 7_ 86- 5.63 1527 1398 1298 8 82 5.53 1482 1360 1260 9- 47 3.17 1482 1410 1260 10 35 2.49 1408 1356 1197 11- 26 1.83 1420 1381 1207 12~ 32 2.21 1448 1400 1231

=13 11 0.74 1480 -1464 1258 14 28 1.91 1468 1426 1248 15 34 2.41 1414 1363 1202 16 71 4.87 1457 1351 1238 17 62 4.21 1473 1380 1252 18 74 5.02 1473 1362 1252 19 64 4.24 1510 1414 1284 20 -129 8.39 1537 1344 1306 21 185 12.10 1531 1254 1301 22- 18 1.22 1477 1450 1255 23 33 2.30 .1432 1383 1217 24 27, 1,82 1487 1487 1264 Total Average Sublimation Rate for Row-9 Baskets = 4.-27 %/yr Notes 1. -The sublimation rates are calculated on-an annual basis (versus a 9 month rate)_because the majority of the data was recorded during refueling outages that fell on a 12 month cycle.

2. Actual data from last TS ice weighing surveillance.

3. Projected minimum average ice weights all exceed design basis limit of 1109 pounds.

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ATTACHMENT 3 Determiration of No Significant Hazards Considerations Duke Power has evaluated the proposed TS change and has determined that it does not represent a significant hazards consideration bared upon the criteria established in 10 CFR 50.92(c). Operation of Cat awba Nuclear Station in accordance with the proposed amendment will not:

(1) Involve a cignificant. increase in the probability or consequencas of an accident previously evaluated.

Duke Power proposes to modify the Catawba Nec1 car Station Unit I and Unit 2 TSs to revise Surveillance Requiremert /,.6.5.1.b. to allow extension of the 9 month ice weighing interval to 18 months. Duke is requesting an extension to allow the ice weighing coincident with the refueling outages.

The total ice bed weight and the minimum average ice basket weights are being ir. creased to account for a 15% sublimation rate over the 18 month interval.

The Ice Condenser is provided to absorb the thermal energy release following a LOCA or steam line break inside Containment and thereby limiting the peak Containment pressure. The current design analysis is based upon a minimum average ice weight of 1109 lbs. per basket.

Calculations using past Ice condenser sublimation data indicate that the total ico b ed weight will not fall below that value assumed in the safety analysis.

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

Duke Power's reque-t for an 18 month ice weighing interval will not result in a new or different kind of accident from that previously analyzed in Catawba's Final Safety Analysis Report. Catawba's Ice Condenser serves to

-limit the peak p; essure inside Containment following a LOCA. Duke Power has evaluated past Ice Condenser sublimation data and has determined that a 15% allowance for subU. nation is conservative for an 18 month interval.

-The proposed TS lee weights derived from the safety analysic weight plus additional allowances of 15% for sublimation and 1.1% for weighing errors will-ensure that tne ice bed will not decrease below that design basjs

' weight. Therefore, the peak Containment pressure assumed in the safety analysis is still valid.

The structural stability of the Ice Condenser will not be affected by the increased ice weights Jn the proposed TS. Current ico loading practices result in newly loaded ice baskets well ir excess of the TS limits. 1 The existing structural design of the Ice Condenser has sufficient margin l to conservatively bound the various loading combinations resulting from j maximum ice loading and accident induced loads. '

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. ('3 ) Involve a significant reduction in a margin of safety.

-The_-Ice Condenser is designed to limit the Containment pressure below the design pressure for all reactor coolant-pipe break sizes up to and including a double-ended severance. Because the minimum required ice l weight assumod in the safety analysis is not being altered, the margin of )

safety as described in the Peak Containment Pressure' Transient is not '

impacted. ]

Tho Ice Condenser also serves as a-Containment air purlfication and ,

cleanup system by absorbing molecular lodine from the containment  !

! atmosphere.following a LOCA. -The required boron concentration (at Jeast l 1800-ppm) and pH (9.0 - 9.5) of the stored ice is not affected by this TS I change. request. Therefore, the air purification aspects of the Ice l Condenser remain unenanged by this submittal and the margin of safety is i not adversely impacted.

P.nvironmental Impact

'The proposed Technical-Specifleation change has been reviewed against the criteria of 110 ~ CFR 51.22 for envircnmental considerations. As shown above, .the proposed change does not involve a significant hazards

-consideration,- nor increase individual.or cumulative occupational radiation' exposures. Based on this, the-proposed TS change meets t.he criteria given inL10 CFR-Sl.22(c)(9) for a categorical exclusion from the requirement'for at enalronmental-impact statement, i

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