Text

Proposed Tech Specs 3.6.1.8 & 3.7.6 Re Carbon Adsorber Test Method & Methyl Iodide Penetration Criteria
	ML20072V038
Person / Time
Site:	Mcguire, McGuire
Issue date:	04/11/1991
From:	; DUKE POWER CO.
To:	;
Shared Package
ML20072V036	List: ML20072V032; ML20072V038;
References
	NUDOCS 9104220004
	Download: ML20072V038 (17)
	v • d • e

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gTTACBMENT 9104220004, 910411 PDR ADOCh 05000 %9 P PDR

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gc; C,0NTAINMENT SYSTEMS n ;'

C ANNULUS VENTILATION SYSTEM LIMITING CONDITION FOR OPERATION h

.3 3.6.1.8 Two independent Annulus Ventilation Systems shall be OPERABLE.

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APPLICABILITY: H0 DES 1, 2, 3, and 4.

+.!I r emen s che r h n W-Wq sec g CC c ACTION: p re- -h eedrt- e s 4eMe d i n 4 4 ' I' M 0 y _

%. / 9.d 5-ith one Annulus Ventilation System inoperabl , restore the inoperab stem 0d

+ d to OPERABLE status within 7 days or be in at 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

ast HOT STANDBY within the next

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-p SURVEILLANCE REQUIREMENTS dj

$+ 4. 6.1. 8 Each Annulus Ventilation System shall be demonstrated OPERABLE:

1 Ci.O'O C a. At least once per 31 days on a STAGGERED TEST BASIS, by initiating, g) g ') from the control room, flow through the HEPA filters and charcoal

3. g o adsorbers and verifying that the system operates for at least 10 oga+ hours with the pre-heaters operating;

[0EL. g b. At least once per 18 months, or (1) after any structural maintenance o5 t on the HEPA filter or charcoal adsorber housings, or (2) following

,C r g y painting, fire, or chemical release in any ventilation zone communi-

, g pfg cating with the system, by:

1#60 1) Verifying that the ventilation system satisfies the in-place

@$Ti 4 k 0 penetration and bypass leakage testing acceptance criteria of less than 1% and uses the test procedure guidance of Regulatory

b Positions C.S.a, C.S.c and C.S.d of Regulatory Guide 1.52,

] n ;c ( Revision 2, March 1978, and the system flow rate is 8000 cfm i o 5 10%;

d# d

$ +j 2) Verifying within 31 days af ter removal that a laboratory analysis of a representative carbon sample obtained in i4 +" 2 (

C accordance with Regulatory Position C 6.b of Regulatory Guide

> d d -j, W . ond .52, Revision 2. March 1978 4 meet; the 1:beratopy-testing-d 4eM ed p r Arit:ri: Of Regulatory-Poe4t4cn C. S. --of-Regu14tery-Gtede--Ir52, p]S 3 o--< gderm 1

j ui RWisien 2, "erch 1070, for-a methyl iodide penetration of less D310S- 1 -1% (Unit 2), and : t: the 1 beeatocy-test 4ng-cM4eMe-o&

f .e gU c. C *o # m gulat0ry P001ti0n C. S. a-of-Regu 44toey- uG ide 1. 52, Rev454en-2,

O 9 ~-March 1978, 4 s u p p l emented-by- ASTM-038M-BMe tt-Method-Ar-4 e N-e 4- * **

d E OO 3) Verifying a system flow rate of 8000 cfm i 10% during system L i M &o - operation when tested in accordance with ANSI H510-1975.

'9e 2hO 4

$0 ef+-spee414eet4eHoc-Unit 1+jdChihi: Opeo414 eat 4en-foe-Un&t 1 ha44-epHy-unt44, July 15,1001.Thereafter, 1 ha!! reed-the-seme-as fcr-UnR j 6 T ]v +f g

) $ 5 o. HcGUIRE - UNITS 1 and 2 3/4 6-16 -Ameedment-No409-@n4-t -l-}--

-Amenement Nc. 9HUnft-2-)-

.6

CONTAINMENT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

After every 720 hours0.00833 days 0.2 hours 0.00119 weeks 2.7396e-4 months of charcoal adsorber operation, by verifying within 31 days after removal that a laboratory analysis of a repre-cmcl ke.SYed p n DTm03S63%s P sition C.6.bntative carbonGuide of Regulatory sample tt-the-+eboratory-testi1ng-eet-teria-o H egulatory-Position-Cv6;a--

obtained 1.52. Revision in accordance 2, March 1978, with R gO '

+f hgelatocy-Gelde-1r6h4ev4s40n-A-Maech4M8r-foe a methyl iodide penetration of less thanpMt 2), end-meet; the 1cberatory-

to ting criteMe-of4egu4etory P 54 tion-Gr6ra--of hgaletery-Gufde-h52, Rev+efon 2, ".croh4978, cs-supp4 . ted by ASTM-0380F66r-Teet-Hethod4, foe-a-methy4-4oet4e-penetMA4en-o es han-Or7-1%-(Mait-1P; H] At least once per 18 months, by:

d. 9 O/6

1) Verifying that the pressure drop across the combined HEPA filters and charcoal adsorber banks is less than 6 inches Water Gauge while operating the system at a flow rate of 8000 cfm i 10%;

(, 2) Verifying that the system starts automatically on any q

Phase B Isolation test signal;

) 3) Verifying that the filter cooling electric motor-operated bypass valves can be opened;

4) Verifying that each system produces a negative pressure of greater than or equal to 0.5 inch W.G. in the annulus within 22 seconds after a start signal and that this negative pressure goes to -3.5 inches W.G. within 48 seconds after the start signal. Verifying that upon reaching a negative pressure of

-3.5 inches W.G. in the annulus, the system switches into its recirculation mode of operation and that the time required for the annulus pressure to increase S. s eater than or equal to 278 seconds; A+ A I oo VAc. .

n o m o. \ Vo hop

5) Verifying that the pre-heaters dissip e4. e.- Wmn.t 2) and 43.0 ^ 0.4/-17.5 kW-(Unit 1)* when tested in accordance with ANSI N510-1975.

e. Af ter each complete or partial replacement of a HEPA filter bank, by verifying that the HEPA filter bank satisfies the in place penetration and bypass leakage testing acceptance criteria of less than 1% in accordance with ANSI H510-1975 for 00P test aerosol while operating the system at a flow rate of 8000 cfm t 10%; and

f. After each complete or partial replacement of a charcoal adsorber bank, by verifying that the charcoal adsorber satisfies the in-place penetration and bypass leakage testing acceptance criteria of less than 1% in accordance with ANSI N510-1975 for a halogenated hydrocarbon refrigerant test gas while operating the system at a flow rate of 8000 cfm i 10%.

his spec 444catier for--Unit 1 shM4-app 4y-unt44-4*1y IS ,1001. Thereaftee,

-tM4-spe c i f i c:ti e n f o r -UM&-1--sha44-vead-the- same- as-fee-Uni-t-2.

McGUIRE - UNITS 1 and 2 3/4 6-17 Ameedment-Ho-lO9(Mn+t-M Amandment-Ho-91(Un4t 2)

[q) C

q. y . .

t w5o-.Tc PLANT SYSTEMS hd +o CONTROL AREA VENTILATION SYSTEM OCW[3/4.7.6 0C LIMITING CONDITION FOR OPERATION .

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.c 'U "o 3.7.6 Two independent Control Area Ventilation Systems shall be OPERABLE.

g {w 3 APPLICABILITY: ALL MODES n

e. 'C" j ACTION: (Units 1 and 2)

Q. 3 0 ye o .5 MODES 1, 2, 3 and 4:

$dT n O gf hith one Control Area Ventilation System inoperable 4 restore the inoperable P I

C d

system to OPERABLE status within 7 days or be in at least HOT STANDBY within e next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTOOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months . #h'

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c o .~t M S 5 and 6: cn D t u -:

Je a. With one Control Area Ventilation System inoperable 4 restore the g '

V inoperable system to OPERABLE status within 7 days ~or initiate ano maintain operation of the remaining OPERABLE Control Area Ventilation ph Ey

[ .c .4 i System in the recirculation mode; and

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kM O CL 7 ,

-o o . - b. With both Control Area Ventilation Systems inoperabl4 or with the O

OPERABLE Control Area Ventilation System, required to be in the recirculation mode by ACTION a. , not capable of being powered by an {I4-vr j OPERABLE emergency power source, suspend all operations involving c.

CORE ALTERATIONS or positive reactivity changes. t g )9 g/

E,j $ \ The provisions of Specification 3.0.4 are not applicable. O-s a.

W SURVEIL CE REQUIREMENTS f

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/ '18 2 4.7.6 Each Control Area Ventilation System shall be demonstrated OPERABLE:

h a. At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , by verifying that the control room air temperature is less than or equal to 90 F; l kh-g vi$ b. At least once per 31 days on a STAGGERED TEST BASIS, by initiating, from the control room, flow through the HEPA filters and charcoal l.6 3~8 % adsorbers and verifying that the system operates for at least 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months with the heaters operating; t [5 "Wo. o QC .70 n*

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2ye Men =cnt- u. I ng49gg_3p

I'5_$McGUIRE-UNITS 1and2 3/4 7-13 Q, mn=etu.90(unu n-i

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PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

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c. . At -least once per 18 months, or (1) af ter any structural maintenance on the HEPA filter or charcoal adsorber housings, or (2) following painting, fire or chemical release in any_ ventilation zone l- communicating with the system, by:

1)' Verifying that the system satisfies the in-place penetration and. bypass leakage testing acceptance criteria of less than 1%

and uses the test procedure guidance of Regulatory Positions C.5,a, C.S.c, and C.S d of Regulatory Guide 1.52, Revision 2, March 1978,.and the system flow rate is 2000 cfm i 10%;

2) Verifying, within 31 days after removal, that a laboratory

, j analysis-of a representative carbon sample obtained in L

QGCk NNO-l N accordance with Regulatory Position C.6.b of Regulatory Guide 5 0q gg., 1 M, Davition 2. March 1978. :::t: the hier;teey-test 4Mg-l O ev4teri: Of R:gul:tery pes 4 tion C.S.: ef-Regulatory-Guide-1r62r i

R:Vf:ien 2 "

H than4 IX,C. - ch r 1^70, for a methyl todida penetration of less l Verify

o. 5%

3) tem flow rate of 2000 cfm i 10% during system operation when tested in accordance with ANSI N510-1975, a

d. After every_720 hours of charcoal adsorber operation, by verifying within 31 days after removal, that a laboratory analysis of a

--QOCA MN k representative osition C.6.b carbon sample obtained of Regulatory in accordance Guide 1.52, Revision 2, with March Regulatory 1978, STrrf p3703-8 --te the l eer:tery te: ting crit:ri: Of R:g; htery "e;itica C.S.s ef R:;; h tery Cuid: 1.52, R:vi: fen 2 ".:rch 197", fcr a methyl 1

hab iodide penetration of less than ^ L .,,, l

e. At least once per 18 months, by: O Mo/o -

1) Verifying that the pressure drop across the combined' pre-filters HEPA. filters and charcoal adsorber banks is less than 5 inches Water Gauge while operating the system at a flow rate of 2000 cfm i 10%;

2) -Verifying that upon actuation of a diesel generator sequencer the system automatically switches into a mode of operation with flow through the HEPA filters and charcoal adsorber banks;

3) Verifying that the system maintains the control room at a positive pressure of greater than oc equal to 1/8 inch W.G.

relative to th side a du s em o eration; and Verifying that A+ Cnosno3 9oh&f4 be oc.

, 4) e hea e s dissipate 10 1 1.0-k w en tested-in accordance with ANSI N510-1975.

McGUIRE - UNITS 1 and 2 3/4 7-14 >::ntent N .108 (lMt-1-}-

. .unhnt Mc. 90 (ifnM+)-

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PLANT SYSTEMS

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SURVEILLANCE REQUIREMENTS (Continued) l f. After each complete or partial replacement of a HEPA filter bank, by verifying that the HEPA filter bank satisfies the in place penetration and bypass leakage testing acceptance criteria of less than 1% in accordance with ANSI H510-1975 for a 00P test aerosol while operating the system at a flow rate of 2000 cfm + 10%; and g, After each complete or partial replacement of a charcoal adsorber bank, by verifying that the charcoal adsorber satisfies the in place penetration and bypass leakage testing acceptance criteria of less than 1% in accordance with ANSI N510-1975 for a halogenated hydro-carbon refrigerant test gas while operating the system at a flow rate of 2000 cfm 1 10%.

McGUIRE - UNITS 1 and 2 3/4 7-15

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PLANT SYSTEMS BASES STANDBY NUCLEAR SERVICE WATER PONO (Continued)

The limitations on minimum water level and maximum temperature are based on providing a 30-day cooling water supply to safety-related equipment without exceeding their design basis temperature and is consistent with the recommend-ations of Regulatory Guide 1.27, " Ultimate Heat Sink for Nuclear Plants,"

March 1974. The Surveillance Requirements specified for the das inspection will conform to the recommendations of Regulatory Guide 1.127, Revision 1, March 1978.

3/4.7.6 CONTROL AREA VENTILATION SYSTEM The OPERABILITY of the Control Area Ventilation System ensures that:

(1) the ambient air temperature does not exceed the allowable temperature for continuous duty rating for the equipment and instrumentation cooled by this system, and (2) the control room will remain habitable for operations personnel during and following all credible accident conditions. Cumulative operation '

of the system with the heaters on for 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months over a 31-day period is fficient to reduce the buildup of moisture on the adsorbers and HEPA filters. The Mm I OPERABILITY of this system in conjunction with control room design provisions %re^\

is based or limiting the radiation exposure to personnel occupying the contro1 4gq((,c room to 5 ren or less whole body, or its equivalent. This limitation is consistent with the requirements of General Design Criterion 19 of Appendix A, 10 CFR 50. ANSI N510-1975 will be used as a procedural guide for surveillance testing.

3/4.7.7 AUXILIARY BUILDING FILTERED VENTILATION EXHAUST SYSTEM The OPERAPILITY of the Auxiliary Building Filtered Ventilation Exhaust System ensures that radioactive materials leaking from the ECCS equipment within the auxiliary building following a LOCA are filtered prior to reaching the environment. The operation of this system and the resultant effect on offsite dosage calculations were assumed in the accident analyses. ANSI N510-1980 will be used as a procedural guide for surveillance testing. The methyl iodido penetration test criterion for the carbon samples has been established at 10% (i.e., 90% removal) which is greater than the iodine removal in the accident analysis.

McGaire - UNITS 1 and 2, B 3/4 7-4 Amendment No. 113(Unit 1)

Amendment No. 95(Unit 2)

l CONTAINMENT SYSTEMS BASES 3/4.6.1.7 REACTOR BUILDING STRUCTURAL INTEGRITY This limitation ensures that the structural integrity of the containment I reactor building will be maintained comparable to the original design standards j for the life of the facility. Structural integrity is required to provide:

! (1) protection for the steel vessel from external missiles, (2) radiation

- shielding in the event of a LOCA, and (3) an annulus surrounding the steel

--f-- vessel that can be maintained at a negative pressure during accident condi-d tions. A visual inspection is sufficient to demonstrate this capability, h 3/4.6.1.8 ANNULUS VENTILATION SYSTEM IA The 0PERABILITY of the Annulus Ventilation System ensures that during LOCA G4 conditions, containment vessel leakage into the annulus will be filtered through g the HEPA filters and charcoal adsorber trains prior to discharge to the atmos-Cumulative operation of the system with the heaters on for 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months ever hE .phere..a 31-day _.ngriod i to reduce the buildup of moisture on the adsorbers sufficient and HD A filters. Thh r:;;ir==t h necessary to meet the arsumptions used in V) the accident analyses and limit the SITE BOUNDARY radiation doses to within the

' dose guideline values of 10 CFR Part 100 during LOCA conditions. ^MS! 9510-1975 A will be un d :: : prn:dur:1 guid; f r surecilkne: t:: ting. AS~,0300P 00, T:st-

" thed A, will bc =d for Unit i =re:ill== t::th; (ht:=t j tect) f r q . = thy' f edid: penetretier " 'ieu of th: ht:r:terj mt :p=Phd in tgehterje QN Cuid: 1. 52, R=. 2, ": h 1978, R:gulet:rj P :i ti= C. S. :. The AST" 0300P00 tut =thed S used- fer : rehth:- hu;;;idity Of 95% :t -3?C. The us: Of tMs M

40:t =d the acceptance-c4teeten Of-: methyl--fed 4d: penetreti = Of 1:4: th=

-0.71% : : ==htent with =:rd d= ntri , thn :f f hkr.:in Of 95%. Th+s s

-ch=ge re:ulted *= lown-VE-syst= h=t:r =p=ity = Unit 1.

3/4.6.1.9 CONTAINMENT VENTILATION SYSTEM The containment purge supply and exhaust isolation valves for the lower compartment (24-inch) and instrument rooc; (12-inch and 24-inch) are required to be sealed closed during plant operations since these valves have not been demonstrated capable of closing during a LOCA. Maintaining these valves sealed closed during plant operation ensures that excessive quantities of radioactive material will not be released via the Containment Purge System.

To provide assurance that these containment valves cannot be inadvertently opened, the valves are sealed closed in accordance with Standard Review Plan 6.2.4 which includes mechanical devices to seal or lock the valve closed, or prevents power from being supplied to the valve operator.

The use of the containment purge lines is restricted to the purge supply and exhaust isolation valves in the upper compartment (24-inch) since, unlike the valves in the lower compartment and instrument room, the upper compartment valves will close during a LOCA. Therefore, the SITE BOUNDARY dose guideline values of 10 CFR Part 100 would not be exceeded in the event of an accident during containment purging operation. Operation with these valves open will be limited to 250 hours0.00289 days 0.0694 hours 4.133598e-4 weeks 9.5125e-5 months during a calendar year.

Leakage integrity tests with a maximum allowable leakage rate for contain-ment purge supply and exhaust supply valves will provide early indication of resilient material seal degradation and will allow opportunity for repair before gross leakage failures could develop. The 0.60 L leakage limit of Specifica-tion 3.6.1.2b. shall not be exceeded A en the leakage rates determined by the i leakage integrity tests of these valves are added to the previously determined total for all valves and penetrations subject to Type B and C tests.

McGUIRE - UNITS 1 and 2 B 3/4 6-3 Amendment No.109(Unit 1)

Amendment No. Q1(Unit 2)

(

/ . Because the carbon adsorber filter decontamination efficiency is verified by the ASTM 03803-89 test method without the use of the moisture reducing heaters, the decontamination efficiency used in the dose calculation is not dependent on heater operation. The heaters serve to reduce the moisture buildup in the carbon filters and extend the useful filter life.

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$ g ATTACHMENT 2

i McGUIRE NUCLEAR STATION TECHNICAL SPECIFICATION CHANGE REQUEST BACKGROUND During a review of the HVAC systems at Catawba Nuclear Station it was discovered that the pre-heaters in some ESF filter units were not conservatively sized for all postulated operating modes. A station specific review revealed that this problem also applied to McGuire. The pre-heaters are used to control the relative humidity of the influent air entering the carbon adsorber. These filters were designed in a manner that assumes the heaters maintain the relative humidity of the air at 70% or less. Duke Power's review revealed that during postulated low voltage conditions with loss of one of the two offsite power sources and all plant auxiliaries of the unit aligned to the other power source through the remaining step-up transformer with a concurrent LOCA, sufficient power may not be supplied to these heaters to enable them to maintain the less than or equal to 70% relative humidity. The affected systems are the Annulus Ventilation System and the Control Area Ventilation System.

Five (5) different options were considered for permanently addressing this relative humidity problem. The options were:

1) Increase the minimum voltage available

2) Provide supplemental heaters

3) Restrict upper flow limit

4) Reduce upper and lower flow limits

5) Change carbon test to factor in high humidity (95%)

Option (1) was rejected since this solution would create problems during normal operation. The low voltage concern is the result of a rare series of events outlined earlier.

Increasing the minimum voltage to provide enough heater capacity during a low voltage event would cause over voltage concerns during normal operation.

Option (2) was rejected because the additional heaters and associated controls are costly and would make the system needlessly more complex. This option would also require additional emergency power during loss of preferred power conditions, reducing the spare power margin available on the diesels.

Option (3) would require that the flow be restricted through the filter units. This would allow the heaters to properly control humidity in a degraded bus situation. This option was rejected because of the increased operator burden caused by the flow restrictions. With the flow margin reduced, operators would have a very restrictive flow range which could lead to system unavailability.

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+ . .

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2 Option (4) would relieve the flow margin restriction of option

-(3)Eby decreasing _the-lower-flow parameter. Even though there is no increased operator burden with option (4), it was rejected because of possible increases in dose. consequences. ,

This is most apparent in the Annulus Ventilation System.

~

Reducing the flow range would increase the time required to draw the annulus to a negative pressure which significantly 1 increases _the Exclusion Area Boundary (EAB) (2. hour) thyroid dose. For the Control Area Ventilation System, pressurization of the control room to the TS required pressure would be i difficult to obtain at the lower flow = parameter, j option (5) involved changing the carbon penetration test method to factor in high-humidity. This option was chosen even_though-it will require a change to the TS and will require more frequent carbon change-out. The benefits of this option are' J

(1) no increased burden on operator due-to flow restrictions, (2)-was the subject of early discussions between the NRC and ii '

Duke Power and appeared to be the option the NRC wanted Duke Power _to pursue (reference temporary Technical Specification 3 change submitted 5/9/90), and (3) no increase or change in the '

dose consequences. This option does increase operator burden by requiring more frequent carbon change out, however, this is acceptable to the station.

PURPOSE :

The purpose of this Technical Specification amendment is to address humidity control associated with the Annulus VentilationE(VE) and the Control Area Ventilation (VC) Systems.

TERMS The-following-terms are defined as they-apply to this document and-to provide clarity to the discussion.

1)- . bypass leakage (BL) - the percentage of flow that passes around a filter without being filtered.

2) penetration (PE) - the amount of methyl iodide which will pass through a sample of carbon without being-adsorbed. This value can be established by testing per ASTM D3803-89.

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3

3) decontamination ef ficiency (DE) - the percent of radioactive iodine that will be removed by a filter system. This value is a function of bypass leakage and penetration.

DE : 100% - (BL + PE)

4) carbon filter efficiency - same as decontamination efficiency.

CHANGES TO TECHNICAL SPECIFICATIONS AND TECHNICAL DISCUSSION

1. CHANGES TO TS The Surveillance Requirement (SR) 4.6.1.8.b.2, 4.6.1.8.c, 4.7.6.c.2, and 4.7.6 d are changed to indicate that the laboratory testing criteria of ASTM D3803-89 will be used.

TECHNICAL JUSTIFICATION The proposed carbon testing standard, ASTM D3803-89, is a stringent procedure for establishing the capability of new and used activated carbon. The following table compares this standard with the original TS required test method and ASTM D3803-86 (temporary TS test method for Annulus Ventilation) for used carbons.

Test Period Original ASTM D3803-86 ASTM Test Method Test Method A D3803-89 Pre- not required not required 30*C 95%RH Equilibration 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months Equilibration not required not required 30*C 95%RH 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Challenge 80*C 70%RH 30*C 95%RH 30*C 95%RH (Feed) 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months The major difference between the ASTM D3803-89 and the other test methods is that the ASTM D3803-89 method requires the carbon beds to be pre-conditioned with 30*C and 95% relative humidity air for eighteen (18) hours before the methyl iodide challenge (food) period. This

4 approach is intended to make the carbon test repeatable so that results from similar tests can be compared. The pre-conditioning is conservative because it saturates the carbon beyond the conditions expected during Design Basis Events for the Annulus Ventilation and control Area Ventilation Systems. The watnr vapor competes with the methyl iodide for adsorption sites on the carbon, therefore, the higher the relative humidity the harder it is for methyl iodide to be adsorbed. ASTM D3803-89 is a more repeatable test for carbon adsorber, and the pre-equilibration period at 95% relative humidity makes it more stringent than previous standards.

2. CHANGES TO TJ SRs 4.6.1.8.b 2 and 4.6.1.8.c are changed to indicate that a methyl iodide penetration of 4% will be used for the Annulus Ventilation System and 4.7.6.c.2 and 4.7.6.d are changed to indicate that a methyl iodido penetration of 0.95% will be used for the Control Area Ventilation System as the acceptance critoria for carbon adsorber testing.

TECHNICAL JUSTIFICATION Reference to the test criteria of Regulatory Guide 1.52 will be removed from TS 4.6.1.8 b.', 4.6.1.8.c, 4.7.6.c.2 and 4.7.6.d, because the Regulatory Guide, Revision 2, March 1978, does not address the testing of a system without humidity control which operate outside the primary containment.

Because of the pre-equilibration period, which does not exist in previous carbon adsorber test standards, the carbon is tested at a more conservative point. Using the ASTM D3803-89 testing standard would always be expected to give a more conservative methyl iodido penetration value than current test methods. The ASTM D3803-89 test method is also conservative with respect to the plant conditions expected during an accident. Postulated accident conditions do not subject the carbon to saturated conditions, therefore, the radioactive iodine penetration during an actual accident would be lower than that predicted by the lab. A 4% methyl iodide penetration is acceptable for the Annulus Ventilation System and a 0.95%

methyl iodido penetration is acceptable for the Control Area Ventilation System since added conservatism is built into the new carbon adsorber test, and current Design Bases decontamination efficiencies are met using this value.

Duke Power believes that this method for defining penetration is conservative for the following reasons:

i

5 a) The scope of ASTM D3803-89 describes this standard as "a very stringent procedure" and says that it "is recommended for the quantification of the degradation of used carbons."

b) Limited testing done by Duke Power shows that testing done per the 1989 revision of ASTM D3803 will result in more frequent carbon change out than testing per the 1986 revision is used. Per this TS change, Duke Fower will generally have newer, fresher carbon in its filter systems.

c) The 1989 revision also requires that the carbon be pre-saturated before being tested. Saturating the carbon limits its ability to adsorb iodine.

Postulated accident scenarios do not subject the carbon adsorber to saturated air, therefore, testing i per the 1989 revision will yield conservative results relative to actual adsorption ability.

I d) Design basis dose analysis for McGuire show that the combination of all ESF systems (ie., containment I sprays, ice condenser, HEPA and carbon filters) and I most importantly the containment itself, serve to keep offsite and onsite doses well below regulatory .

limits. The relative importance of the carbon l adsorbers to mitigate iodine releases is questionable in light of source term studies over the laet decade which predict only a small elemental iodine constituent in the release.

3. CHANGES TO TS The ACTION for TS 3.6.1.8, Annulus Ventilation System, and 3.7.6, Control Area Ventilation System,.are changed to indicate that they apply for reasons other than pre-heaters. New ACTIONS have been added to indicate that if the heaters are inoperable, they will be fixed within 7 days, or a report filed with the NRC.

TECHNICAL JUSTIFICATION Since the Design Basis decontamination efficiencies can be met'for the Annulus and the Control Area Ventilation Systems using a test that assumes no heaters, operability of the systems will no longer be dependent on heater operability. The heater testing requirements will remain the same as they'are currently, and the heaters will be required to be fixed in a timely manner in the event of failure. Even though the heaters will remain in service, no credit will be taken for them, resulting in additional margin.

6

4. CHANGES TO TS "At a nominal voltage of 600 VAC" has been added to SRs 4.6.1.8.d.5 and 4.7.6.e.4.

TECHNICAL JUSTIFICATION The statement "at a nominal voltage of 600 VAC" has been added to the heater testing requirements. This clarifies how the heater testing should be done. With the heaters tested at a nominal voltage of 600 VAC, a failure of the heater surveillance would be indicative of a heater probler., not a system problem,

5. CHANGES TO iS The sections of TS 3.6.1.8, Annulus Ventilation System, which apply only until July 16, 1991, have been deleted.

This change is administrative in nature.

6. The TS Bases have been marked up to reflect these changes.

NO SIGNIFICANT HAZARDS ANALYSIS 10 CFR 50.92 states that a proposed amendment involves no significant hazards consideration 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 the margin of safety.

This proposed TS amendment will not increase the probability or consequences of an accident which has been previously evaluated. No physical changes wil.1 be made to the plant, therefore, there is no increased probability of an accident.

As discussed in the Technical Justification, the decontamination efficiencies of the filters remain unchanged.

Because of this, the offsite dose and Control Room dose calculation results are unaffected. The dose calculations remain conservative due to the conservative assumptions in the source term dose conversion factors and release times. In addition to requiring the carbon adsorber to meet Design Basis decontamination efficiencies at 95% relative humidity, additional margin, for which no credit is taken, will be provided by the heaters. For the reasons stated above, there will be no increase in the consequences of an accident previously evaluated.

This proposed amendment to the TS does not create the possibility of a new or different kind of accident from any accident previously evaluated. This proposed TS change will

7 not cause any physical changes to the plant or changes to operating procedures. Because the plant will continue to operate the same way it does now, this proposed amendment does not create the possibility of any new or different accident from any previously evaluated.

This proposed TS change will not cause a significant reduction in the margin of safety. The new tort method is more restrictive than the previous test methods, and based on limited testing, Duke Power expects to have to change out carbon more frequently. The change in the allowed methyl lodido penetration was made to support the change in test method, does not represent a significant decrease in the margin of safety. It represents the requirement of the test standard to pre-saturate the carbon adsorber. This pre-saturation causes a higher penetration during testing, and is conservative with respect to Design Basis Events. The test method D3803-89 is expected to provide a penetration value during testing which is higher than what would be expected during a Design Basis Event. These conservative results reflect the fact that the new test conditions are more harsh than expected plant conditions. An added conservatism is that even though no credit is taken for the heaters, they will be tested and maintained, so the expected relative humidity of air entering the carbon adsorber would never be expected to reach 95%.

The addition of "at a nominal voltage of 600 VAC" to the heater SR is administrative, and clarifies that the purpose of the requirement is to detect heater degradation. This change involves no significant hazards consideration.

Footnotes and statements related to the footnotes which expire on July 16, 1991 have been removed. This change is administrative, and involves no significant hazards consideration.

The proposed Technical Specification change has been reviewed against the criteria of 10 CFR 51.22 for environmental considerations. As shown above, the proposed change does not involve significant hazards consideration or increase individual or cumulative occupational radiation exposure, Based on this, the proposed amendment meets the criteria given in 10 CFR 51.22(c)(9) for categorical exclusion from the requirements for an Environmental Impact Statement.

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ML20072V038

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