ML20236Y407

Proposed Tech Specs,Increasing Containment Integrated Leak Rate Permitted by Tech Spec 3.6.1.2 to 0.30% Per Day

ML20236Y407
Person / Time
Site:	Catawba
Issue date:	12/03/1987
From:	DUKE POWER CO.
To:
Shared Package
ML20236Y406	List: ML20236Y403 ML20236Y407
References
NUDOCS 8712110302
Download: ML20236Y407 (14)

Text

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O ATTACHMENT 1 PROPOSED TECliNICAL SPECIFICATION REVISION 1

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l 8712110302 071203 PDR ADOCK 05000413 P PDR

1 CONTAINMENT SYSTEMS J

CONTAINMENT LEAKAGii LIMITING CONDITION FOR OPERATION

3. 6.1. 2 Containment leakage rates shall be limite "

a. An overall integrated leakage r e of: g

1) Less than or equal to L,, w t of the containment air per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at P,, . psig, or

2) (Unit 1) Less than or equal to L , 0.122% by weight of the con- l tainment air per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at a rIduced pressure of P,, 7.34 psig. {

b. A combined leakage rate of less than 0.60 L, for all penetrations and valves subject to Type B and C tests, when pressurized to P,,

and

c. A combined bypass leakage rate of less than 0.07 L, for all penetrations identified in Table 3.6-1 as secondary containment l' bypass leakage paths when pressurized to P,.

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

ACTION:

With: . (a) the measured overall integrated containment leakage rate exceeding 0.75 L, or 0.75 L t, as applicable, or (b) the measured combined leakage rate for all penetrations and valves subject to Types B and C tests exceeding 0.60 L,, or l' (c) the combined bypass leakage rate exceeding 0.07 L,, restore the overall integrated leakage rate to less than 0.75 L, or less than 0.75 Lt , as applicable, and the combined leakage rate for all penetrations and valves subject to Type B and C tests to less than 0.60 L,, and the cor.bined bypass leakage rate to l

less than 0.07 L prior to increasing the Reactor Coolant System temperature a

above 200*F.

l SURVEILLANCE REQUIREMENTS l

4. 6.1. 2 The containment leakage rates shall be demonstrated at the following test schedule and shall be determined in conformance with the criteria soeci- l 1

fied in Appendix J of 10 CFR P. art 50 using the methods and provisions of ANSI  !

N45.4-1972 or the mass plot method:

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

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ATTACHMENT II DISCUSSION AND ANflYSIS 0; NO SIGNIFICANT HAZARDS CONSIDERATIONS l

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DISCUSSION AND ANALYSIS OF NO SIGNIFICANT HAZARDS CONSIDERATIONS The proposed amendment to Technical Specification 3.6.1.2 would allow an increase in the overell integrated leak rate (La) for the Catawba containment building.

Design basis dose calculations have been updated by implementing the revised NRC Standard Review Plan (SRP) Section 6.5.2 such that credit for iodine removal by containment boric acid sprays could be assumed. Calculations indicate that for iodine activity, a 50% increase in the containment leakager'ete tends to offset the spray removal credit. Since noble gases are unaffected by containment sprays, there was an increase in the whole body and skin doses. However, for Catawba thyroid exposure is the limiting criteria; and the whole body and skin doses are still well within 10 CFR 100 and GDC 19 values. For this reason, there is sufficient technical justification for relaxing the containment leakage rate acceptance criteria to 0.30% per day from its current value of 0.20% per day.

Below, a tabular comparison is provided for the current and revised calculations for offsite and control room operator LOCA doses.

Chapter 15, FSAR Calculation - Current Catawba Control Room LOCA Dose (Rem)

Whole Body Thyroid Skin

.46 25.9 9.0 Catawba DBA LOCA Dose (Rem)

Exclusion Area Boundary Low population Zone Whole Body Thyroid Whole Body Thyroid 2.99 115.0 7.61E-01 50.8 Chapter 15, FSAR Calculations - Spray Removal Credit, 50% Containment Leakage Rate Increase l

Catawba Control Room LOCA Dose (Rem)

Whole Body Thyroid Skin '

.70 18.9 14.0 Catawba DBA LOCA Dose (Rem)

Exclusion Area Boundary Low population Zone Whole Body Thyroid Whole Body Thyroid 4.47 131.0 8.63E-01 29.7 {

New source term (applications would provide further technical justification which have not been assumed in these conservative calculations. For example, the chemical form of iodine post-LOCA is believed to be primarily CsI rather than I2 '

Containment sprays are much more effective at removing lodine in particulate form rather than the assumed elemental form.

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) The proposed amendments would not result in exceeding any cafety limits during normal operatisu or design basis accident conditions.

This same Technical Specification amendment request has been reviewed and approved for our McGuire Nuclear Station (see NRC letter dated March 5, 1986). During the NRC Staf f review of the McGuire submittal additional information was requested  !

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DISCUSSION AND ANALYSIS OF NO SIGNIFICANT HAZARDS CONSIDERATIONS (see letter dated October 15, 1985 from Ms. E. G. Adensam, NRC/NRR, to Mr. H. B.

Tucker, Duke Power Company). The following is a response to those questions as they relate to Catawba.

(1) Effective sprayed containment volume The containment is equipped with two 100 percent capacity return air f an systems, each of which uses a 40,000 cfm fan to force air from the upper compartment back to the lower compartment, and thus provide a homogeneous mixture of steam and air throughout the containment. Therefore, the effective sprayed contagnmegt volume was assumed to be the containment net-free volume of 1.015 x 10 ft.

(2) pH of the spray The following are post-accident recirculated water chemistry characteristics:

pH 8.3 to 8.5 ppm boron 1900 to 2100 (3) Containment sump volume, or alternatively, the volume available for containment spray recirculation The post-LOCA containment sump liquid volgme available for containment spray recirculation was assumed to be 90,122 ft j 1

j (4) _ Effective spray drop height l 1

The distance from the six spray ring headers to the operating deck ranges from 99 ft. to 109 ft.

(5) Elemental, organic, and particulate iodine removal coefficients ( e, c, and p) for the containment sprays From SRP 6.5.2 guidance, the maximum elemental iodine decontamination facter, DF, was calculated to be 5.87. Reference NUREG/CR-0009, " Technological Bases for Models of Spray Washout of /.irborne Contaminants in Containment Vessels," conservatively assumes a DF of 100 for particulate iodine removal.

No credit was taken for spray removal of organic iodines.

The elemental lodine removal coefficient, e, was calculated based on the most conservative boric acid spray elemental iodine removal test presented in NUREG/CR-0009. The most conservative test (i.e., slowest removal rate) j I results in e equal to .912 hr . The particulate iodine removal coefficient,  !

p, was calculated based on spray cut-o{f time and a particulate DF equal to 100. The calculated p equals 2.37 hr . The organic iodine removal coefficient, o, was assumed to be 0.

t (6) Brief description of spray model used in the calculation Discussed adequately in the above responses.

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DISCUSEION AND ANALYSIS OF NO SIGNIFICANT HAZARDS CONSIDERATIONS 10 CFR 50.92 states that a proposed amendment involves no significant hazards considerations if operation in accordance with the proposed amendment would not:

(1) Involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) Create the possibility of a new or different kind of accident from any.

accident previously evaluated; or (3) Involve a significant reduction in a margin of safety.

The proposed amendment Joes not involve a significant increase in the probability or consequences of any previously evaluated accident. The analysis presented above shows that all applicable regulatory requirements will still be met.

This proposed revision will not create the possibility of a new or different' kind of accident from any accident previously evaluated. The design, construction and allowed modes of operation of the plant will be unaffected by this change.

The proposed amendment does not involve a significant reduction in a margin of safety. As shown above, all' applicable regulatory requirements will still be met upon approval of this proposed Technical Specification amendment.

The Commission has provided guidance concerning the application of the standards in 10 CFR 50.92 by providing certain examples (48 FR 14870) of actions involving no significant hazards considerations. One of the examples (vi) involves a change which either may result in some increase to the probability or consequences of a .

l previously ' analyzed accident or may reduce in some way a safety margin, but where the results of the change are clearly within all acceptable criteria with respect to the system or component specified in the Standard Review plan; for example, a change resulting from the application of a small refinement of a previcusly used calculational model or design method. The proposed amendment matches the example because the doses after a design basis LOCA with the increased containment leakage rate, but with allowance for the containment spray system, would remain below the acceptance criteria for radiological exposure in Appendix A of SRp 15.6.5 and in SRp 6.4. Other criteria in the SRp sections would not be affected l by the proposed change.

For the reasons stated above, it is concluded that the proposed amendment does not involve significant hazards considerations.

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l ATTACHMENT III REVISED FSAR PAGES I

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?. . 50 percent of the iodines and 100 percent of the noble gases in tr,e melted fuel are released.

3. 50 percent of the iodine released are deposited in the sump.

4. Annulus activity which is exhausted prior to the time at which tre U.nulus reaches a negative pressure of -0.25 in.w.g. is unfiltered.

5. ECCS leakage occurs at twice the maximum operational leakage.

6. ECCS leakage begins at the earliest possible time sump recirculation can l begin.

7. Bypass leakage is '7 percent.

8. The effective annulus volume is 50 percent of the actual volume.

9. The annulus filters become fouled at 900 seconds resulting in a 15 percint reduction in flow.

10. Elemental iodine removal by the ice condenser begins at 600 seconds anc continues for 3328.3 seconds with a removal efficiency of 30 percent.

11. One of the containment air return fans is assumed to fail. t

12. The containment leak rate is 50 percent of the Technical Specifications limit after 1 day.

13. Iodine partition factor for ECCS leakage is 0.1 for the course of the accident.

14. No credit is taken for the auxiliary building filters for ECCS leakage.

15. The redundant hydrogen recombiners and igniters fail. Therefore, purges are required for hydrogen control.

(The following assumptions apply to the secondary side analysis).

16. All the activity released is mixed instantaneously with the entire reactor coolant volume.

17. The primary to secondary leak rate is 1 gal / min.

18. The iodine partition factor is 0.1.

19. The steam release terminates in 120 seconds.

20. All noble gases which leak to the secondary side are released.

21. The primary ar.d secondary coolant concentrations are at the maximum allowed by technical specifications.

Based on the foregoing model, the primary and secondary side releases may be calculated as well as the offsite doses. The doses, given in Table 15.4.8-2, 15.4-35

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22. Elemental and particulate iodine removal from the containment atmosphere by containment spray begins at the initiation of the event andycontinues for 116 minu and 3.95E-02 minutes {eswithsprayremovalLAMBDASof1.52E-02

, respectively. minutes i

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Table 15.4.8-2 (Page 2)

Parameters for Postulated Rod Ejection Accident Analysis Conservative Realistic 0.1 percent of 0.025 percent containment vol- of containment uma per day, volume per day, t>24 he t>24 hr

c. Bypass leakage fraction 0.07 0.07

d. Iodine partition factor for steam 0.1 -

release

e. Offsite power Lost -

f. Steam dump fros relief valves (1b) 44500. -

g. Duration of dump from relief valves 120. -

(sec)

3. Dispersion data g

a. Distance to exclusion area boundary (m) 762. 762. ,

b. Distance to low population zone (m) 6096. 6096.

c. x/Q at exclusion area boundary (sec/m3 )

0-2 hrs 5.5E-04 1.3E-04

d. X/Q at low population zone (sec/m3 ) j 0-8 hrs 1.8E-05 6.2E-06 I l

8-24 hrs 1.2E-05 5.4E-06 l 1-4 days 4.3E-06 2.5E-06 4+ days 1.2E-06 9.7E-07

4. Dose data .

a. Method of dose calculation Regulatory same Guide 1.77 4 l

b. Dose conversion assumptions Regulatory Guides same l 1

1.4 and l'.109

c. Doses (Rem)

Primary side Exclusive area boundary 6 7- OA Whole body Thyroid M 5.5 l

Table 15.4.8-2 (Page 3)

Parameters for Postulated Rod Ejection Accident Analysis Conse Realistic Low population zone /. 2 6- o 2.

Whole body M Thyroid 4rt fg j Secondary side Exclusion area boundary Whole body 3.3E-02 Thyroid 1.2 Low population zone Whole body 1.1E-03 Thyroid 3.8E-02 i

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5. ECCS leakage occurs at twice the maximum operational leakage.

6. Bypass leakage is 7 percent.

7. The effective annulus volume is 50 percent of the actual volume. l

8. The annulus filters become fouled at 900 seconds resulting in a 15 percent reduction in flow.

9. Elemental iodine removal by the ice condenser begins at 600 seconds and 1 continues for 3328.3 seconds with a removal efficiency of 30 percent. i

10. iJne of the containment air return fans is assumed to fail.

11. The containment leak rate is fifty percent of the Technical Specification limit after i day. l

12. Iodine partition factor for ECCS leakage is 0.1 for the course of the l accident. ,

13. No credit is taken for the auxiliary building filters for ECCS leakage.

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14. The redundant hyrdogen recombiners and igniters fail. Therefore, purges are required for hydrogen control, g The doses are presented in Table 15.6.5-10 and are within the limits of 10 CFR 100.

• Control Room Operator Oose The maximum postulated dose to a control room operator is determined based on the releases of a Oesign Basis Accident. In addition to the parameters and assumptions listed above, the following apply:

1. The control room pressurization rate is 4,000 cfm; the filtered recircula- 3 tion rate is 3,000 cfm.  ;

2. The unfiltered inleakage into the control room is 10 cfm.

3. Other assumptions are listed in Table 15.6.5-11.

15.6.6 A NUMBER OF BWR TRANSIENTS Not applicable to Catawba. l

% s. t sa ad pusa ick ccmoa ecw Me conhuoment ahnasphece. f con %nmen+ spray heyns ah

' +ke iniMaban cd he eyed ad conknues for Ith inlndu

& Spwy rern om/ MMDAs of /. 52 E-oz. min uks~' aal 3.'15 E- o 2. vrvaaki', respec^lWely.

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Table 15.6.5-10 (Page 3)

Parameters for LOCA Offsite Dose Analysis Conservative Realistic

c. Doses (Rem)

Case 1 (with ECCS leakage) U Exclusion Area Boundary Whole Body q#

e e, a , / I3 6*02 Thyroid ^ ~ ~ ' "'

Low Population Zone ~. - 6.6E- o/

Whole Body Thyroid 1((;3[ _3 Case 2 (Without ECCS leakage)

Exclusion Area Boundary Whole Body M'

• Thyroid N -/,2Ecoz Low Population Zone Whole Body 7. C: ',1 --- 8. 6 (-of Thyroid 6 Z,SS+o, g 1

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Table 15.6.5-11 (Page 2)

Parameters for LOCA Control Room Dose Analysis Conservative R_ealistic

3. Dispersion data - Control room intake x/Q (sec/m3) 0-8 hrs 9.9E-04 8-24 hrs 7.2E-04 1-4 days 5.1E-04 4+ days 2.8E-04 j

4. Dose data

a. Method of dose calculations Standard Review Plan 6.4 i

b. Oose conversion assumptions Regulatory Guides 1.4, 1.109 ,

c. Coses (Rem)

N, 7.0E-of '- )

Whole body l Thyroid N /,9Efo/ J Skin M~ l .'lE+ o f i

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