DRYWELL BYPASS AND DRYWELL AIRLOCK TESTING

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Attachment 3-

GNRO-93/00122^

of 8 :-

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PCOL-93/13'

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DRYWELL BYPASS AND DRYWELL AIRLOCK TESTING!

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MARK-UP OF AFFECTED TECHNICAL SPECIFICATIONS |

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9310260344 931022 ~4

PDR ADOCK 05000416 .

P PDR 4 |

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DEFINIT 10NS Attachment 3-

GNRO-93/00122 |

of 8DRYWELL INTEGRITY

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1.10 DRYWELL INTEGRITY shall exist when:

All drywell penetrations required to be closed during accidenta.conditions are either: ;

1. Capable of being closed by an OPERABLE drywell automaticisolation system, or :

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2. Closed by at least one manual valve, blind flange, ordeactivated automatic valve secured in its closed position,except for valves that are opened under administrative controlsas permitted by Specification 3.6.4. ,

b. The drywell equipment hatch is closed and sealed.The drywell airlock is in compliance with the requirements ofc.Specification 3.6.2.3. -

d. The drywe 1 1 a e rates are within the limits of Specification-2.5.2.2< .6 2..). I

The suppress d is in compliance with the requirements ofe.Specification 3.6.3.1. J

f. The sealing mechanism associated with each drywell penetration;e.g., welds, bellows or 0-rings, is OPERABLE.

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GRAND GULF-UNIT 1 1-2a Amendment No.4M |-

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Attachment 3,

GNRO-93/00122CONTAINMENT SYSTEMS of 8

3/4.5.2 DRYWELL

DRYWELL INTEGRITYi

LIMITING CONDITION FOR OPERATION

3.6.2.1 DRYWELL INTEGRITY shall be maintained.P

APPLICABILITY: OPERATIONAL CONDITIONS 1, 2L*>and 3.|

ACTION:'

Without DRYWELL INTEGRITY, restore DRYWELL INTEGRITY within I hour or be in atleast HOT SHUTDOWN within the next 12 hours and in COLD SHUTDOWN within thefollowing 24 hours.

SURVEILLANCE REOUIREMENTS

4.6.2.1 DRYWELL INTEGRITY shall be demonstrated:

At least once per 31 days by verifying that all drywell penetra-a.

tions** not capable of being closed by OPERABLE drywell automaticisolation valves and required to be closed during accident conditionsare closed by valves, blind fit.nges, or deactivated automatic valvessecured in position, except for valves that are opened underadministrative control as permitted by Specification 3.6.4.

b. By verifying the drywell air lock is in compliance with therequirements of Specification 3.6.2.3.

By verifying the suppression pool is in compliance with thec.

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d. By verifying drywell bypass leakage is less than or equal to 10% of the bypassleakage limit at least once per 10 years. If any drywell bypass leakage rate test failsto meet the specified limit, the test frequency shall be increased to 36 months; if thesubsequent consecutive test meets the limit, the above ten year test schedule may beresumed. If two consecutive tests fail to meet the limit, a test shall be performed atleast once every 18 months until two consecutive tests meet the limit, at which timethe above test schedule may be resumed.

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* Scc Spccid Tcst Occptica 3.10.1.L**Except valves, blind flanges, and deactivated automatic valves which are

located inside the drywell or containment and are locked, sealed or otherwisesecured in the closed position. These penetrations shall be verified closedduring each COLD SHUTDOWN except such verification need not be performed moreoften than once per 92 days.

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GRAND GULF-UNIT 1 3/4 6-13 Amendment No. E 402

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Attachrnent 3-

~ GNRO-93/00122 of 8

CONTAINMENT SYSTEMS

DRYWELL BYPASS LEAKAGE

LIMITING CONDITION FOR OPERATION. _ ,

Mc.keu-3.6.2.2 *0r7.:J? bypass-leekege-shall be lese then er aquei 1: 10% f-the -o

-ettept:51: */JE design v:!ue of 0.90 ft A2 .

-AF AMC4BI LITY. L' hen-ORYWEM:-ENTEGRETY is required per Spee+f4eetien 3.5.2.1.1-

-ACT40 Q

-With the cry.<cil bypest-leekage greatee-than-10% of th: ::ceptab1: */[tcc:ign t 32--value of 0. 90 f t , restore-the-drywel' bypes: 10:k:ge t: witki- the 'imit '2.- prior to incre ing re::ter :: 1:nt :ystem t::p:ratur: :bev: 200 " t

- SURVEILLANCE REQUIREMENTS

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4. 6.2.2 -The-drywell-bypass-leakage-rate-test-shall-be-conducted at le St.cnce 't-per-.18-months-at :n initial different4*l-pressure of 3.0 p;id :nd th: ^//h ':-sha 14-be-calcu la t ed-f+om-the-se a sveed-leek age. 0 ^.: d ryer " - i ' " d ^ ^ * 'h*'' o

ranin-open-during-the-drywel+-leakege-test-strehd*at esch dry.;:l' deer !! leak 1-tested-dur4r,9-at-4 east-every-other cry.;:11 1:ekage r:1+-testr-

If :ny d f.;;1' bypass-leakage-rate-test-f4445-to-meet the :peci'ied t-a .-14mitr-the-test-schedule-for-subrepuent tests shel1 be -edewad ad a

s-approved-by-the-Gemmission. If tve-eentecwtive tests-feil tc . meet ^u.= tn; tirit, a test-shell be perfcraed st-4eest ence every ^ s,enth; t ienti' t=0 censecutive-tests-meet-the-14mit, :t dich-t4:: the abeve cte:t :chedul: may-be-re:= ed.-c.

b. air-locks-sha44-be-tested :nd dezen:trated-CP4AABLE p:r Survei!!:n : c4etttirement 4.5.2.3. -0

The prov4540ns-of- Spec 4f4 cat 4:n *.0.2 :re not :pplic:ble. t-c.>

GRAND GULF- '1 3/4 6-14 Amlwed o. _

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CONTAINMENT SYSTEMS Attachment 3-

GNRO-93/00122DRYWELL AIR LOCK

of 8


3.6.2.3 The drywell air /Tock shall be OPERABL *tt M ,

Both decri closad except ' hen the ei- 10ck i; being u;cd for ncrmc! transittc.

entry-and--exit through the dry"cll, then-at-4 east-one air icck deer indi'rt-be-closed, endt

b. in over-all-air-4oc4-leakage rate of 1000 than et -et P , 11.5 p;ig.A qual tc 2 sef per hcm La

APPLICABILITY: OPERATIONAL CONDITIONS 1, '* and 3.ACTION: ,

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Withonedrywellairflockdoorinoperabl(,

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-1.Mainta4n-at les:t the OPBARLE ai- !cck dooe-cleted and either re:terec-the in0per:ble ci- !cck door to OPERABLE- Status 'ithia 24 50er: Or b i-leck the OPEPABLE air leck deer !c::d. Operat4en may then esntihue -L--provided-that-the-@ERABLE air !cck-dcer i ^;crified te be 10 kedh-c hred at least--ent per 31-day:. Othe r.ci:0, b: ir at 100:t 90T e, o. ,vn~ m, um u_ __m ,, m __

m ~ . . . m , . .e n ~ ,. . m >- . . , - :.J t E W { W W R 61 5 bll 3 il bf 3G 14 G A b A 6. 3 4WW I J G3 fM 4 44 bV6W .bilV I 'a/V MIT W 5 bd3515 bliC'--f0!!ceing 24 heure. u

b. uit3 t3e 37ymey, 35 7ee i4,gpe73373, exg,pg 33 3 7 egg 7t gy 37 4,gpg7333v

-ai- lock dece, :34atair at least one ai- lock deer c!csed; *estere thet ji

noperable aia lock te OPEPABLE status eithia 24 keur: ,

=iiOT SWTBOWN-within-the-next-42-hours--and4n-40LD4H9T00* withiaOr be iat le :t-L '

'0!! wing 24 hours. the -t !

-c. With end rye:11-a te-lock-doop-inf4atable-seal-system-sea 4-pr e s : u r e

-4ns-trumentation channsi- inopacable, restere the inoperable chennal s

-GPERABLE-status-within-7-days-oe-vee 44y-the-essoc4ated-inf4atable :::1 atot'

--pressure-to4s 160 prig -at least once par-12 hours a._.

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3 50: Special Test Excepticn 3.10.1.L

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GRAND GULF-UNIT 1 3/4 6-15 Amendment No. O

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Attachment 3- GNRO-93/00122

CONTAINMENT SYSTEMS of B

SURVEILLANCE REQUIREMENTS

ellairjiockshallbedemonstratedOPERABLE:4.6.2.3t e. |....-,.'..-...h.. '.'.a..4.a.'', . . . . a a '. " . . . . '.h.. . 4, ' ' . - ' . , , ' , 3, , e

a. -.+..4" " . . ' ' ' " +. *.

- , 7 . . . , ,

, , . .. m i. +. 4. m, i. . . g+. ,. 4 . , .w......a

e . , ,3, .s .u. . . _ _ #.u.,

... .. . . ., . . . . . +. 3.. +.... ... . , :__ o....,..i. 3. .c .. .... . . . . . . . ,

3..,, +w.. m3 .. , , ., ,,

i .s s , us__-2,,,,, x.. .- g. . . . . _m up r. ., s.v ._... ... .. .y . .. a. w. .. __ m,u....__. . u.. s.... ..3.,. 4. ..

, ggg y.,..,,.4...a.+.,a,, ...c .

4.. . . . . . ..,, o. . - . . . . .. ... ...

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b. Byconductinganoverallairffockleakagetesta 11.5 psig-

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and veri ing that the overall air ock leakage ra e is dthi- '.t;^_~liai t "^ 6 2. sc.idicist one_a pc.r- le rno .

L,e c . . r.n , n .e u.n.i. nn.uuw .n. ... . --

4< . . ,. . < s u. . . s. 4. . + u. . .., ... e..

_ _ _ m. . - o. . . .. ...... .. .. ,...... . . ....m , m

_ .e . o.4. . . . , . . . . w i. 4. , w. 4 . .,. , n. o. vv..eri. v. u. .r. e.r e. . v. r. y .1...__ ..,.t._o._____-__-. .. .. ....

teen perfe---d ca..- .. <_- e. o ..u.o . mu ~

the e4a 'cek + hat eeu'd eff:;; the .ir icck "_.. 31.. . ,.w434.m o's ~y,---*~-= su

ig QQAt least once per 18 months by verifying that only one door in thec.

g airflock can be opened at a time. I

|*"d. 4 ., ". .4'.,"4..a,a . . = . . " ..4.'...'. d.^^* 4-''..-*...'.'..- ~ . . ' . ,,-t...""""'"'"",."

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n.mmmetestinn ameh ef the twa 4mflafshla emal men e t tira O.-tastr-wmentatic.a chen e' per cir!cct de5r'6os*1"~E by ; wfer eacet--e#--a+--.

s ru.,uu.e,. ene. rt. t. e.x. . n. . v. e.e t. .3. ... ____ ___ ,a., .. ___.u... . . . _ _ , .. .. ... . . . . . y., .. ..~m. ., m

.s i P.u.a.DW E t P..a.t. T. .E D. A T. i n. W.+. 1. . . e +. . . . .... ... ,o ..-+k. _

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w 4 + h. _. I. m. . r, rus , s .. ..+...e. .,; .6 ,- = I, , . s^f.A

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z.,. n. .. 3..... .. .. 3 .s,... .....,,,,,,e.s, _2, _..__,,_,__ _ _ ,,__u.... . . . . ... , ,,,,, g...... . _ . . _ ,. . _ _ _ _ _ _ _

4e--gr4ater- then er -aue1 te on peig. a_0. .',t leed--ence-per 18 :: nth:, 4* ducting : :e:' pn: retic ey?t-- ( !

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-4 &a>._ +. u.. ,. . m.s. oe,. 4 o.<m..,, +w.+. . . . .,o..,._ . 40ev.. a.... . .. . s. . . . ,o -e..._. . .g.. p. .. ..._+w. s o,4.,,, e e.n., ,,a, ,4+s4. a se.,,,,

.... .%,,,

......7 -- ,.4.

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# v s . . ,m., 4. , 4. ,. . . , .e...,,1__ __.. ....,.,,o, n , ___ _m _ _ , ,_ n.g.,_._,.r.. . .... . r.w.,n. ..s

GRAND GULF-UNIT 1 3/4 6-16 Amendment No. -34 (-

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Attachment 3.

GNRO-93/00122 of 8

oTS 3/4.6.2.3 Insert A l7

NOTES

1. Entry and exit is permissible to perform repairs of the affected airlock components.

2. Required ACTION a is not applicable if both doors in the airlock are inoperable and IACTION c or d is entered. j

t3. Entry and exit is permissible for 7 days under administrative controls. '

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!,TS 3/4.6.2.3 insert B |y

, within 1 hour, venfy the OPERABLE door is closed, and within 24 hourslock the OPERABLE door closed. Operation may continue provided that the OPERABLE door is )

verified by administrative means to be locked closed at least once per 31 days. Otherwise, enter.

IACTICN d. '

NOTES

1. Required ACTION b is not applicable if both doors of the airlock are inoperable andACTION c or d is entered. )

2. Entry and exit is permissible under the control of a dedicated individual.

b. With the drywell airlock interlock mechanism inoperable, within 1 hour, verify an OPERABLE door isclosed, aM within 24 hours lock an OPERABLE door closed. Operation may continue provided that anOPERABLE door is verified by administrative means to be locked closed at least once per 31 days.Otherwise, enter ACTION d.

With the drywell airiock inoperable for reasons other than ACTIONS a or b, immediately initiate actionc.

to evaluate drywell overall leakage rate per LCO 3.6.2.1, "Drywell Integrity," using current airlock testresults, and within 1 hour, verify a door is closed, ag restore airlock to OPERABLE status within 24hours. Otherwise, enter ACTION d.

d. With the required ACTIONS a. b, or c (including the associated completion times) not met, be in at leastHOT SHUTDOWN within the next 12 hours and in COLD SHUTDOWN within the following 24 hours.

TS 3/4.6.2.3 Insert C 7_

NOTE

Only required to be performed upon entry into drywell.

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- -Attachment 3 -GNRO-93/00122

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CONTAINHENT SYSTEMS

BASES |

I| CONTAINMENT PURGE SYSTEM (Continued) ;

Leakage integrity tests with a maximum allowable leakage rate for purgesupply and exhaust isolation valves will provide early indication of resilientmaterial seal degradation and will allow the opportunity for repair before i

gross leakage failures develop. The 0.60 L, leaking limit shall not beexceeded when the leakage rates determined by the leakage integrity tests of Ithese valves are added to the previously detemined total for all valves andpenetrations subject to Type B and C tests. ;

3/4.6.2 DRWELL3/4.6.2.1 ORYWELL INTEGRITY

ii

Drywell integrity ensures that the steam released for the full spectrum ),

of drywell pipe breaks is condensed inside the primary containment either byl

the suppression pool or by containment spray. By utilizing the suppression i

pool as a heat sink, energy released to the containment is minimized and the '

severity of the transient is reduced.3/4.6.2.2 DRWELL BYPASS LEAKAGE !

The limitation on drywell bypass leakage rate ensures that the maximum leakagewhich could bypass the suppression pool during an accident would not result in the

|containment exceeding its design pressure of 15.0 psig. The design drywell ;| leakage. rate is expressed a A/5 and has a value of 0.90 ft2 A/ 4 is cependent| only on the geometr of drywell leakage paths where A = flow area of leakage

paths in ft2 and ,K is a lumped constant which considers geometric and frictionloss coefficients such as discontinuities and Reynolds number. At a 3 psiddifferential pressure from drywell to containment an A/8 of 0.90 ft2 has anequivalent mass flow of 35,000 scfm. The integrated drywell leakage value is

1limited to 10% of the allowable drywell leakage capability, which is equivalentto 3500 scfm at 3 psid drywell to containment.

| The A/8 value of 0.90 ft is derived from the analysis of " bypasscapability with containment spray and heat sinks" (FSAR 6.2.1.1.5.5). Thelimiting case accident is a very small reactor coolant system break which willnot automatically result in a reactor depressurization. The long term differen-tial pressure created between the drywell and containment will result in a signi-ficant pressure buildup in the containment due to this bypass leakage.3/4.6.2.3 DRWELL AIR LOCK

fThe limitations on closure for the drywell air lock are required to meetthe restrictions on DRWELL INTEGRITY and the drywell leakage rate given inSpecifications 3.6.2.1 and 3.6.2.2. The specification makes allwances for

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the fact that there may be long periods of time when the air lock will be in Ia closed and secured position during reactor operation. Only one closed door

| in the air lock is required to maintain the integrity of the drywell. h'

ver"ic.tien that =h ei- un er urhubh heliyet- h eEuntt- by the per'e-eace ef e !ocal hek-detectien test 'e" a PMd of h55 *"t'8 hourt te pa-hsibh if it een be trnstreted that the heter ratetcan be accurately ete-bed fer thh :hcrte pe-4ed. Thh h %-acewhwith Secticas 6.1 end 7.6 ef AuSI k25.A-107? (

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GRAND GULF-UNIT 1 B 3/4 6-3 Amendment No. tb f

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jAttachment 4*

'GNRO-93/00122 |

Page 1 of 8 . |

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PCOL-93/13

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DRYWELL BYPASS AND DRYWELL AIRLOCK TESTING |

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INFORMATIONAL COPY OF PROPOSEDt

TECHNICAL SPECIFICATION PAGES

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GNRO-93/00122 !.

Page 2 of 8DEFINITIONS

DRYWELL INTEGRITY j

1.10 DRYWELL INTEGRITY shall exist when:

a. All drywell penetrations required to be closed during accident conditions areeither:

1. Capable of being closed by an OPERABLE drywell automatic isolationsystem, or

2. Closed by at least one manual valve, blind flange, or deactivatedautomatic valve secured in its closed position, except as provided inTable 3.6.4-1 cf Specification 3.6.4.

b. The drywell equipment hatch is closed and sealed.c. The drywell airlock is in compliance with the requirements of Specification

3.6.2.3.d. The drywell leakage rates are within the limits of Specification 3.6.2.1. |3

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The suppression pool is in compliance with the requirements of Specificatione.3.6.3.1.

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f. The sealing mechanism associated with each drywell penetration; e.g., welds,~

bellows or 0-rings, is OPERABLE.

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Amendment No. |

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Attachment 4 --. GNRO-93/00122 i

Page 3 of 8 .

CONTAINMENT SYSTEMS |

3/4.6.2 DRYWELL ]DRYWELL INTEGRITY


3.6.2.1 DRYWELL INTEGRITY shall be maintained. *

APPLICABILITY: OPERATIONAL CONDITIONS 1,2, and 3.|

ACTION:;

Without DRYWELL INTEGRITY, restore DRYWELL INTEGRITY within 1 hour or be in at least HOT ISHUTDOWN within the next 12 hours and in COLD SHUTDOWN within the following 24 hours,

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SURVEILLANCE REQUIREMENTS,

4.6.2.1 DRYWELL INTEGRITY shall be demonstrated:

a. At least once per 31 days by verifying that all drywell penetrations" not capable of :

being closed by OPERABLE drywell automatic isolation valves and required to beclosed during accident conditions are closed by valves, blind flanges, or deactivatedautomatic valves secured in position, except for valves that are opened under'

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administrative control as permitted by Specification 3.6.4.

b. By verifying the drywell airlock is in compliance with the requirements of Specification3.6.2.3.

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c. By verifying the suppression pool is in compliance with the requirements ofSpecification 3.6.3.1.

:d. By verifying drywell bypass leakage is less than or equal to 10% of the bypass'

.!leakage limit at least once per 10 years. If any drywell bypass leakage rate test failsto meet the specified limit, the test frequency shall be increased to once every 36

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months; if the subsequent consecutive test meets the limit, the above ten year testschedule may be resumed. If two consecutive tests fail to meet the limit, a test shall )be performed at least once every 18 months until two consecutive tests meet the*

limit, at which time the above test schedule may be resumed. ;

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I" Except valves, blind flanges, and deactivated automatic valves which are located inside the~

drywell or containment and are locked, sealed or otherwise secured in the closed position. Thesepenetrations shall be verified closed during each COLD SHUTDOWN except such verificationneed not be performed more often than once per 92 days.

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Amendment No. |

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. Attachment 4GNRO-93/00122

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Page 4 of 8 jCONTAINMENT SYSTEMS ,

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DRYWELL BYPASS LEAKAGE j

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LIMITING CONDITION FOR OPERATION,

3.6.2.2 deleted

SURVEILLANCE REQUIREMENTS

4.6.2.2 deleted

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GNRO-93/00122 !,

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CONTAINMENT SYSTEM4

DRYWELL AIRLOCK '

LIMITING CONDITION FOR OPERATION >

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3.6.2.3 The drywell airlock shall be OPERABLE. i

APPLICABILITY: OPERATIONAL CONDITIONS 1,2, and 3. !

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ACTION: i

NOTES

1. Entry and exit is permissible to perform repairs of the affected airlock.'

components.

2. Required ACTION a is not applicable if both doors in the airlock are inoperable -

and ACTION c or d is entered.

3. Entry and exit is permissible for 7 days under administrative controls.ii. _ ___.

a. With one drywell airlcck door inoperable, within 1 hour, verify the OPERABLE door isclosed, and within 24 hours lock the OPERABLE door closed. Operation maycontinue provided that the OPERABLE door is verified by administrative means to belocked closed at least once per 31 days. Otherwise, enter ACTION d.

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NOTES |

1. Required ACTION b is not applicable if both doors of the airlock are inoperable ;'

and ACTION c or d is entered.i

2. Entry and exit is permissible under the control of a dedicated individual.'

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b. With the drywell airlock interlock mechanism inoperable, within 1 hour, verify anOPERABLE door is closed, and within 24 hours lock an OPERABLE door closed.Operation may continue provided that an OPERABLE door is verified byadministrative means to be locked closed at least once per 31 days. Otherwise, enter i

ACTION d.

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GNRO-93/00122 i,

Page 6 of 8 ;

c. With the drywell airlock inoperable for reasons other than ACTIONS a or b,immediately initiate action to evaluate drywell overall leakage rate per LCO 3.6.2.1, |

i"Drywell Integrity," using current airlock test results, and within 1 hour, verify a door isclosed, and restore airlock to OPERABLE status within 24 hours. Otherwise, enter i

ACTION d. t

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d. With the required ACTIONS a, b, or c (including the associated completion times) notmet, be in at least HOT SHUTDOWN within the next 12 hours and in COLDSHUTDOWN within the following 24 hours.

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Amendment No. j

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GNRO-93/00122 i,

Page 7 of 8

CONTAINMENT SYSTEMSl

SURVEILLANCE REQUIREMENTS'

4.6.2.3 The drywell airlock shall be demonstrated OPERABLE:

a. deleted

b. By conducting an overall airlock leakage test at 2 11.5 psig and verifying that theoverall airlock leakage rate is 5; 2 scfh at least once per 18 months.

NOTE

Only required to be performed upon entry into drywell.

c. At least once per 18 months by verifying that only one door in the airlock can beopened at a time.

d. deleted

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Amendment No. |

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%*# Attachment 4<

GNRO-93/00122,

Page 8 of 8

CONTAINMENT SYSTEMS

BASES

3/4.6 2 DRYWELL

3/4.6 2.1 DRYWELL INTEGRITY

Drywell integrity ensures that the steam released for the full spectrum of drywell pipebreaks is condensed inside the primary containment either by the suppression pool or bycontainment spray By utilizing the suppression pool as a heat sink, energy released to thecontainment is minimized and the severity of the transient is reduced.

3/4.6.2.2 DRYWELL BYPASS LEAKAGE

The limitation on dryweli bypass leakage rate ensures that the maximum leakagewhich could bypass the suppression pool during an accident would not result in thecontainment exceeding its design pressure of 15.0 psig. The design drywell leakage rate isexpressed a A/ W and has a value of 0.90 ft . Al K is dependent only on the geometry2

2of drywell leakage paths where A = flow area of leakage paths in ft and k is a lumpedconstant which considers geometric and friction loss coefficients such as discontinuities andReynolds number. At a 3 psid differential pressure from drywell to containment an Al E of0.90 ft2has an equivalent mass flow of 35,000 scfm. The integrated drywell leakage value islimited to 10% of the allowable drywell leakage capability, which is equivalent to 3500 scfmat 3 psid drywell to containment.

The A/ E value of 0.90 ft is derived from the analysis of " bypass capability with2

containment spray and heat sinks"(UFSAR 6.2.1.1.5.5). The limiting case accident is a verysmall reactor coolant system break which will not automatically result in a reactordepressurization. The long term differential pressure created between the drywell andcontainment will result in a significant pressure buildup in the containment due to this bypassleakage.

3/4.6.2.3 DRYWELL AIR LOCK

The limitations on closure for the drywell airlock are required to meet the restrictionson DRYWELL INTEGRITY and the drywell leakage rate given in Specifications 3.6.2.1 and3.6.2.2. The specification makes allowances for the fact that there may be long periods oftime when the airlock will be in a closed and secured position during reactor operation. Onlyone closed door in the airlock is required to maintain the integrity of the drywell.

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Amendment No.

DRYWELL BYPASS AND DRYWELL AIRLOCK TESTING

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