Text

Proposed Tech Specs Re Drywell Leak Rate Testing Requirements
	ML20094M800
Person / Time
Site:	Grand Gulf, River Bend
Issue date:	11/20/1995
From:	; ENTERGY OPERATIONS, INC.
To:	;
Shared Package
ML20094M789	List: ML20094M800; RBG-42193, Rev to Application for Amend to License NPF-29 & Proposed Amend to License NPF-47,revising TS 3/4.6.2.2, Drywell Bypass Leakage;
References
	GNRO-95-00128, GNRO-95-128, NUDOCS 9511270237
	Download: ML20094M800 (51)
	v • d • e

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GNRO 95/00128 and RBG42103 Attachment 3 Page1 Mark-up of Affected Technical Specifications and Bases Drywell Leak Rate Testing Requirements Grand Gulf Nuclear Station l

PEA 22;gggzoggggj13 Grand Gulf P PDR

GNRO-9A0128 and RBG-43193 Attachment 3 Page 2 DryWelI 3.6.5.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.5.1.1

NOTE---------------]---

No equirad to performe ntil ent into E 2 on the rst plant art-up from the ight refuel outage.

...)

Verify bypass leakage is less than or t equal to the bypass leakage limit. =

"fn 5s.ri ,l However, during the first unit startup 3,L- 53 A following drywell bypass leak rate L testing performed in accordance with this SR, the acceptance criterion is leakage 1 10% of the bypass leakage limit.

SR 3.6.5.1.2 Visually inspect the exposed accessible Once prior to interior and exterior surfaces of the performance of drywell. each Type A test required by SR 3.6.1.1.1 3.4-536

(.T. ose.cN GRAND GULF 3.6-53 Amendment No. 120

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GNRO-95/00128 and RBG-43193 Attachment 3 Page 3 INSERT 3.6 53A 24 months following 2 consecutive tests with !

I bypass leakage greater l

than the bypass leakage limit until 2 consecutive tests are less than or equal to the bypass leakage limit M

48 months following a

' test with bypass leakage greater than the bypass leakage limit ,

M

....N OTE SR 3.0.2 is not applicable for extentions > 12 months.

120 months INSERT 3.6 538 SR 3.6.5.1.3 Verify drywell air lock leakage by performing an 24 months ,

air lock barrelleakage test at 2 3 psid. ;

i Grand Gulf

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GNRO-95/oo128 and RBG42193 j

i Anacnwnt 3 Pape 4 Orywell Air Lock 1 3.6.5.2 1

3.6- CONTAINMENT SYSTEMS 3.6.5.2 Drywell Air Lock LCO 3.6.5.2 The drywell air lock shall be OPERABLE.

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APPLICABILITY: MODES 1, 2, and 3. ,

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ACTI0h5 lb

.....................................N0TE$h-----------------------------------

(1) Entry and exit is permissible to perform repairs of the affected air lock m---components.

2. ter applicab Conditions an equired A' ons of LC .6.5.

"O ell," when a lock leauage ults in e eding ov 11 dr 11 bypass akage rate a eptance crite . ,,,_

CONDITION REQUIRED ACTION COMPLETION TIME A. One drywell air lock ------------NOTES------------

door inoperable. 1. Required Actions A.1, A.2, and A.3 are not applicable if both doors in the air lock are inoperable and Condition C is entered. ;

Entry and exit is

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2.

permissible for 7 days under administrative controls.

A.1 Verify the OPERABLE 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months door is closed.

ME (continued)

GRAND GULF 3.6-54 Amendment No. 120

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GNRO-95/00128 and RBG-42193 Attachment 3 Page 5 1

Drywell Air Lock 3.6.5.2 l ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C. Drywell air lock C.1 [itiat action ywell o -!-4

' 4 " =1"AO inoperable for reasons [evluate '

other than Condition A ove 11 le age ra or B. per L 0 3.6. 1, Drywe , " us g c rent gir loc test re its.\ .

C.2 Verify a door is I hour closed.

AND Restore air lock to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months OC.12OPERABLE status.

D. Required Action and D.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time not met. AND l

-f 0.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months j

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GRAND GULF 3.6-56 Amendment No. 120 W

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GNRO-05/00188 and RBG-42193 Attachment 3 Page 6 Orywell Air Lock

- 3.6.5.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.5.2.1 ------------------NOTE-------------------

Only required to be performed upon entry into drywell.

Verify only one door in the drywell air months lock can be opened at a time.

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QR---3.6.5.b1

_ M inopera

N0 air lock

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does no MT.D inv idate the revious suc sful perfo ce of t verall ai ock y

LCc g g ,g' q 1eakage t.

t----- --------- ----- -

Verifymdrywell air lock leakage _ months 9 "al i: : :'ufs by performi n-t;T air lock leakage test at a: pst .

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CRAND GULF 3.6-57 Amendment No. 120

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f GNRO-95/00138 and RBG-43193 Attachment 3 Page 7 Drywell Isolation Valves ,

3.6.5.3 l 4- 3.6 CONTAINMENT SYSTEMS .

4

) 3.6.5.3 Drywell Isolation Valves LC0 3.6.5.3 Each drywell isolation valve, except for Drywell Vacuum i Relief System valves, shall be OPERABLE. !

APPLICABILITY: MODES 1, 2, and 3. )

l ACTIONS

..................................... NOTES------------------------------------

1. Penetration flow paths may be unisolated intermittently under

administrative controls. 1

2. Separate Condition entry is allowed for each penetration flow path.

3. Enter applicable Conditions and Required Actions for systems made inoperable by drywell isolation valves.

4. ter app cable Co itions a Require Actions LCO 6.5.

"Dr ell," in drywe isolati valve 1 age re ts in cee g

, overa drywe")spypass kage ra accepta crite . ___

i CONDITION REQUIRED ACTION COMPLETION TIME A. One or more . A.1 Isolate the affected 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months penetration flow paths penttration flow path

< with one drywell by use of at least isolation valve one closed and de-inoperable. activated automatic ;

valve, closed manual i valve, blind flange, !

, or check valve with flow through the valve secured.

AR (continued)

GRAND GULF 3.6-58 Amendment No. 120

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j- GNRO-95/co188 and RBG-42193 j Attachment 3 Page8 i B 3.6.5.1 I

} BASES (continued) i ACTIONS A.1 1,

l In the event the drywell is inoperable, it must be restored i to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . The 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Completion i Time provides a period of time to correct the problem

! commensurate with the importance of maintaining the drywell 4

OPERABLE during MODES 1, 2, and 3. This time period also

] ensures that the probability of an accident (requiring j drywell OPERABILITY) occurring during periods when the

drywell is inoperable is minimal. Also, the Completion Time i is the same as that applied to inoperability of the primary

! containment in LCO 3.6.1.1, " Primary Containment."

4 i 8.1 and B.2 i If the drywell cannot be restored to OPERABLE status within

' the required Completion Time, the plant must be brought to.a MODE in which the LCO does not apply. To achieve this i status, the plant must be brought to at least MODE 3 within i 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and to MODE 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The allowed

! Completion Times are reasonable, based on operating

)- experience, to reach the required plant conditions from full

'; power conditions in an orderly manner and without challenging plant systems.

1 I SURVEILLANCE SR 3.6.5.1.1 1

REQUIREMENTS

The analyses in Reference 2 are based on a maximum drywell l bypass leakage. This Surveillance ensures that the actual

, drywell bypass leakage is less than or equal to the i acceptable A/d design value of 0.9 ft 8assumed in the

! safety analysis. As left drywell bypass leakage, prior to j the first startup after performing a required drywell bypass leakage test, is required to be s 107, of the drywell bypass

leakage limit. At all other times between required drywell i leakage rate tests, the acceptance criteria is based on 4 j design A M . At the design A M the containment temperature j and pressurization response are bounded bv the ass maH ans 1 ofthesafetyanalysiA1Theleakagetestisperformedevery}

8 months, consistent with the difficulty of performing the i i test, risk of high radiation exposure, and the remote I 15es7

! possibility that a component failure that is not identified i f 3,g. JoQ g some other drywell or primary containment SR might occur (continued) i i

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. GRAND GULF B 3.6-104 Revision No. O i

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I j GNRO-95/00128 Cod RBG43193 i Attachment 3 Page 9 a

i INSERT B 3.6-104A This Surveillance is performed at least once every 10 years on a performance based frequency.

The Frequency is consistent with the difficulty of performing the test, risk of high radiation exposure, and the remote possibility that sufficient component failures will occur such that the drywell bypass leakage limit will be exceeded, if during the performance of this required Surveillance the drywell bypass leakage rate is greater than the drywell bypass leakage limit the Surveillance Frequency is increased to every 48 months. If during the performance of the )

subsequent consecutive Surveillance the drywell bypass leakage rate is less than or equal to the j drywell bypass leakage limit the 10 year Frequency may be resumed. If during the performance i of two consecutive Surveillances the drywell bypass leakage is greater than the drywell bypass ,

leakage limit the Surveillance Frequency is increased to at least once every 24 months. The 24 l month Frequency is maintained until during the performance of two consecutive Surveillances the drywell bypass leakage rate is less than or equal to the drywell bypass leakage limit, at l which time the 10 year Frequency may be resumed. For two Surveillances to be considered l consecutive the Surveillances must be performed at least 12 months apart.

Since the Frequency is performance based, i

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GNRO-95/00128 and RBG-43193 .

Attachment 3 Page io

Drywell B 3.6.5.1 BASES

, SURVEILLANCE SR 3.6.5.1.1 (continued)

REQUIREMENTS 4

52 p perating pass the experience Suruai11ance has shown when that these oerformed at thecomponents 18 mor th_ usually __

lFrecuenc Derefore, the Frequency was concludec to be

-accep from a reliability standpoint.

SR 3.6.5.1.2 The exposed accessible drywell interior and exterior surfaces are inspected to ensure there are no apparent physical defects that would prevent the drywell from performing its intended function. This SR ensures that drywell structural integrity is maintained. The Frequency was chosen so that the interior and exterior surfaces of the drywell can be inspected in conjunction with the inspections of the primary containment required by 10 CFR 50, Appendix J (Ref. 2). Due to the passive nature of the drywell j g e-h structure, the specified Frequency is sufficient to identify component degradation that may affect drywell structural l 3, (,- I M integrity.

t REFERENCES 1. UFSAR, Chapter 6 and Chapter 15.

2. 10 CFR 50, Appendix J.

GRAND GULF B 3.6-105 Revision No. O

GNRO-95/00138 and RBG-431SG Attachment 3 Paget1 INSERT B 3.6105A SR 3.6.5.1.3 This SR requires a test to be performed to verify air lock leakage of the drywell air lock at pressures 2 3 psid. The 24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for violating the drywell boundary. Operating experience has shown these components usually pass the Surveillance and requires the SR to be performed once each refueling cycle.

Therefore, the Frequency was concluded to be acceptable from a reliability standpoint.

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GNRO-95/00138 and RBG42193 Orywell Air Lock 8 3.6.5.2 l 1

BASES I l

i BACKGROUND /The drywel ir lock does no eed to meet the quirementsh l (continued) I of 10 CFR 50, endix J (Ref. , since it is n part of ,

e primary cont ment leakage b dary. However, t is pr nt to specify eakage rate re irement for the drywe air lock. As 1 leakage rate mit of s 2 sc nd I e ,

an air ck overall leak rate limit or 2 scfh, at ,

- pressure (11.5 psig), ve been establ. ed to assure ]

the integrit f the seal p APPLICABLE Analytical methods and assumptions involving the drywell are SAFETY ANALYSES presented in Reference 2. The safety analyses assume that for a high energy line break inside the drywell, the steam and non-condensibles, with the exception of the allowable .

bypass leakage, is directed to the suppression pool through !

the horizontal vents where it is condensed and fission l product scrubbing occurs. Since the drywell air lock is !

part of the drywell pressure boundary, its design and maintenance are essential to support drywell OPERABILITY, which assures that the safety analyses are met.

The drywell air lock satisfies Criterion 3 of the NRC Policy I Statement.

LC0 The drywell air lock forms part of the drywell pressure boundary. The air lock safety function assures that steam resulting from a DBA is directed to the suppression pool.

Thus, the air lock's structural integrity is essential to the successful mitigation of such an event.

The air lock is required to be OPERABLE. For the air lock to be considered CPERABLE, the air lock interlock mechanism must be OPERABLE, & Ed hd.;; n L .;O,;.,1;nig and both air lock doors must be OPERABLE. The interlock allows only one air lock door of an air lock to be opened at

_' one time. This provision ensures that a gross breach of the

%ggr drywell does not exist when the drywell is required to be 3 S,4,-W7 A PERABLE.

Closure of a single door in the air lock is necessary to support drywell 0PERABILITY following postulated events.

Nevertheless, both doors are kept closed.when the air lock is not being used for entry into and exit from the drywell.

(continued)

GRAND GULF B 3.6-107 Revision No. O j i

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GNRO-95/00128 and R8G-43193 Attachment 3 Page 13 i

INSERT B 3.6-107A Airlock leakage is excluded from this Specification. The air lock leakage rate is part of the drywellleakage rate and is controlled as part of OPERABILITY of the drywellin LCO 3.6,5.1, "Drywell".

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GNRO-95/00138 and RBG 43193 Attachment 3 Page 14 Drywell Air Lock B 3.6.5.2 BASES (continued)

. APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of radioactive material to the primary containment. In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, the drywell air lock is not required to be OPERABLE in MODES 4 and 5.

ACTIONS The ACTIONS are modified by Note 1 that allows entry and exit to perform repairs on the affected air lock component.

If the outer door is inoperable, then it may be easily accessed to repair. If the inner door is inoperable, however, then there is a short time during which the drywell boundary is not intact (during access through the outer door). The ability to open the OPERABLE door, even if it means the_drywell boundary is temporarily not intact, is acceptable dve to the low probability of an event that could pressurize the drywell during the short time in which the OPERABLE door is expected to be open. The OPERABLE door must be immediately closed after each entry and exit.

The ACTI are modified a second Not which en res appropriate dial actions e taken when ecessary.

rsuant to LC 0.6, ACTIONS not requir even if he dr 11 is exceedi its bypass le ge limit. erefore, the N is added to uire ACTIONS r LCO 3.6.5. toAej is event.

Qkenin _ _

1 A.I. A.2. and A.3 With one drywell air lock door inoperable, the OPERABLE door must be verified closed (Required Action A.1). This ensures that a leak tight drywell barrier is maintained by the use

- of an OPERABLE air lock door. This action must be completed within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . The 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Completion Time is consistent with the ACTIONS of LCO 3.6.5.1, "Drywell," which requires that the drywell be restored to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . 4 In addition, the air lock penetration must be isolated by locking closed the OPERABLE air lock door within the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Completion Time. The Completion Time is considered reasonable for locking the OPERABLE air lock door, .

considering that the OPERABLE door is being maintained closed.

(continued)

GRAND GULF B 3.6-108 Revision No. O

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GNRO-95/o0138 and RBG-43193 '

Attachment 3 Page 15 D@l1 Mr M B 3.6.5.2 BASES ACTIONS B.1. B.2, and 8.3 (continued) drywell under the control of a dedicated individual

. stationed at the air lock to ensure that only one door is opened at a time.

C.k _-

, ca.r A With the air lock inoperable for reasons other than those describedinConditionAorB,fequireCActionC.1 requires ction w ue immediately in1T.1ated to evaluate drywell bypass leakage using current air lock test-results. An

. evaluation is acceptable, since it is overly conservative to immediately declare the drywell inoperable if both doors in

& an air lock have failed a seal test or the overall air lock leakage is not within limits. In many instances (e.g., only I

one seal per door has failed), drywell remains OPERABLE, yet

only 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months (per LCO 3.6.5.1) would be provided to restore the air lock door to OPERABLE status prior to requiring a plant shutdown. In addition, even with both doors failing

- the seal test, the overall drywell leakage rate can still bp/

(within limi_ty -

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, kequiredActionC.(requiresthatonedoorinthedrywell air lock must be verified to be closed. This Required Action must be completed within the 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Completion Time.

This specified time period is consistent with the ACTIONS of

.LC0 3.6.5.1, which requires that the drywell be restored to OPERABLE status within I hour.

1 Additionally, the air lock must be restored to OPERABLE status within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . The 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Completion Time is reasonable for restoring an inoperable air lock to OPERABLE status, considering that at least one door is maintained closed in the air lock.

4 O.1 and 0.2 If the inoperable drywell air lock cannot be restored to OPERABLE status within the required Completion Time, the plant must be brought to a MODE in which the LC0 does not 3

apply. To achieve this status, the plant must be brought to at least MODE 3 within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and to MODE 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The allowed Completion Times are reasonable, (continued)

GRAND GULF B 3.6-110 Revision No. O

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! GNRO 95/00138 and RBG-43193 Attachment 3 ' Page 16 Drywell Air Lock

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B 3.6.5.2

BASES ACTIONS D.1 and 0.2 (continued) I l

based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

SURVEILLANCE SR 3.6.5.2.1 REQUIREMENTS The air lock door interlock is designed to prevent simultaneous opening of both doors in the air lock. Since both the inner and outer doors of the air lock are designed to withstand the maximum expected post accident drywell pressure, closure of either door will support drywell OPERABILITY. Thus, the door interlock feature supports drywell OPERABILITY while the air lock is being used for personnel transit in and out of the drywell. Periodic testing of this interlock demonstrates that the interlock

-will function as designed and that simultaneous inner and outer door opening will not inadvertently occur. Due to the nature of this interlock, and given that the interlock mechanisa is only challenged when a drywell air lock door is

(

openea,Ltnis test is nly required to be performed once every @nths. The nth Frequency is based on the need to perform this Surveillance under the reduced reactivity conditions that apply.during a plant outage and the potential for violating the drywell boundary. Operatin g experience has shown- these cogonents usual 1,y pass t Surveillance when performed m-is based on the refueling cycle. Therefore, the Frequency was concluded to be acceptable from a reliability standpoint.

The Surveillance is modified by a Note requiring the Surveillance to be performed only upon entry into the drywell.

W SR 3.6.5. .

+. m$

N 63F This SR requires a test to be performed to verify G* .

air lock leakage o the drywell air lock at pressures 2 7p r'd % !!.S F;i. The month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage an'd the potential for violating the drywell boundary. Operating experience has shown these-components usually pass the Surveillance when performed at (continued)

GRAND GULF B 3.6-111 Revision No. 0

GNRO-95/00128 and RBG-42193 Attachment 3 Page 17 Drywell Air Lock 8 3.6.5.2 BASES SURVEILLANCE 3.6.5.k.[ '

tinued)

REQUIREMENTS 24 the N month Frequency, which is based on the refueling g g cycle. Therefore, the Frequency was concluded to be fo$t. 6 3.4~ bs (_ acceptable from a reliability standpo_ int.

M This R has been ino fied by a e indicati that an inopera e air lock do does not alidate th 3revious ccessfu erformance o overall lock lea e test.

Th is cons red reasonab since ei r air loc oor is ,

capa of prov no a fission oduct bar ' r in the vent I

g f a DB j l

REFERENCES 1. 10 CFR 50, Appendix J. ,

1

2. UFSAR, Chapters 6 and 15.

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GRAND GULF B 3.6-112 Revision No. O

onRo-sstoo138 and RBM2193 AnsW 3 Page 18 OryweII ISOI" yalVe(s) g 3.6.5.3 BASES LC0 they are excluded from this Specification. Controls on (continued) their isolation function are adequately addressed in LCO 3.6.5.6, "Drywell Vacuum Relief System."

E W The normally closed isolation valves or blind flanges are J.rwnM g 34.glg4 considered OPERABLE when, as applicable, manual valves are i

closed or opened in accordance with applicable administrative controls, automatic valves are de-activated and secured in their closed position, check valves with flow through the valve secured, or blind flanges are in place. l The valves covered by this LCO are included (with their ,

associated stroke time, if applicable, for automatic valves)~ !

in the applicable plant procedures. ,

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of radioactive material to the primary containment. In MODES 4 '

! and 5, the probability and consequences of these events are i' reduced due to the pressure and temperature limitations in:

i these MODES. Therefore, the drywell isolation valve (s) are !

j not required to be OPERABLE in MODES 4 and 5.

i ACTIONS The ACTIONS are modified by four Notes. The first Note l allows penetration flow paths to be unisolated

~

intermittently under administrative controls. These j j controls consist of stationing a dedicated operator, who is in continuous communication with the control room, at the i l controls of the valve. In this way, the penetration can be rapidly isolated when a need for drywell isolation is ,

l indicated.

The second Note provides clarification that for the purpose

. of this LCO separate Condition entry is allowed for each

penetration flow path. This is acceptable, since the Required Actions for each Condition provide appropriate compensatory actions for each inoperable drywell isolation

, valve. Complying with the Required Actions may allow for continued operation, and subsequent inoperable drywell isolation valves are governed by subsequent Condition entry and application of associated Required Actions.

! The third Note requires the OPERABILITY of affected systems to be evaluated when a drywell isolation valve is

. inoperable. This ensures appropriate remedial actions are taken, if necessary, if the affected system (s) are rendered inoperable by an inoperable drywell isolation valve.

(continued)

GRAND GULF B 3.6-115 Revision No. 0

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GNRO<5/00138 and RBG-43193 Attachment 3 Pageis INSERT B 3.6-115A Drywell isolation valve leakage is also excluded from this Specification. The drywell isolation valve leakage rates are part of the drywell leakage rate and are controlled as part of OPERABILITY of the drywell in LCO 3.6.5.1, "Drywell".

Grand Gulf

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GNRO-95/co128 and RBG42193 Anachment 3 Page2o Drywell isolation Valve (s) l B 3.6.5.3 '

BASES ACTIONS ihef rth Note sures appro (continued) ken w n the dr 11 bypass 1 iate remediah age ctions limits a excee ]d.

P suant LCO 3.0. these ACTI are not req - ed ev n whe the as ciated LC not met. erefore, No 3

_ % and re add to requir the proper a ions are ta A.1 and A.2 With one or more penetration flow paths 'with one drywell isolation valve inoperable, the affected penetration flow path must be isolated. The method of isolation must include the use of at least one isolation barrier that cannot be adversely affected by a single active failure. Isolation barriers that meet this criterion are a closed and de-activated automatic valve, a closed manual ~ valve, a blind j flange, and a check valve with flow through the valve secured. In this condition, the remaining OPERABLE drywell' isolation valve is adequate to perform the isolation function. However, the overall reliability is reduced because a single failure in the OPERABLE drywell isolation Lnse.d ] valve could result in a loss of drywell _ isolation. T d W)/y UNQesign A 8 hour Completion Time is acceptabledsince it the drywel g Dypass seanage ANk of 3.9 n- were exceeded, ACTIONS E

(NOTE 4willensureappropriate_conservativeactionsare implemented D n ada1 Tion, the. Completion Time is reasonable, considering the time required to isolate the penetration and the relative importance of supporting drywell OPERABILITY during MODES 1, 2, and 3.

For affected penetration flow paths that have been isolated in accordance with Required Action A.1, the affected l penetrations must be verified to be isolated on a periodic !

basis. This is necessary to ensure that drywell ~

penetrations that are required to be isolated following an ,

accident, and are no longer capable of being automatically isolated, will be isolated should an event occur. This Required Action does not require any testing or device manipulation; rather, it involves verification that those devices outside drywell and capable of potentially being mispositioned are in the correct position. Since these devices are inside primary containment, the time period specified as " prior to entering MODE 2 or 3 from MODE 4, if not performed within the previous 92 days," is based on enginesring judgment and is considered reasonable in view of the inaccessibility of the devices and other administrative controls that will ensure that misalignment is an unlikely possibility. Also, this Completion Time is consistent with (continued)

GRAND GULF B 3.6-116 Revision No. 0

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GNRO-95@i28 and RBG-42193 Attachment 3 Page 21 INSERT B 3.6-116A due to the low probability of the inoperable valve resulting in excessive drywell leakage and the low probability of the limiting event for drywell leakage occurring during this short time frame.

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lll GNRO-95/0ol28 and RBG-43193 -

Attachment 3 Page 22 4 Orywell Isolation Valve (s)

B 3.6.5.3 l .

~1

BASES l

l ACTIONS A.1 and A.2 (continued) i i the Completion Time specified for PCIVs in LCO 3.6.1.3, i j " Primary Containment Isolation Valves (PCIVs)."

4 4 Required Action A.2 is modified by a Note that applies to

isolation devices located in high radiation areas and allows i them to be verified by use of administrative controls.

Allowing verification by administrative controls is l considered acceptable, since access to these areas is typically restricted. Therefore, the probability of misalignment, once they have been verified to be in the proper position, is low.

B.1 With one or more penetration flow paths with two drywell isolation valve (s) inoperable, the affected penetration flow path must be isolated. The method of isolation must include the use of at least one isolation barrier that cannot be adversely affected by a single active failure. Isolation barriers that meet this criterion are a closed and de-activated automatic valve, a closed manual valve, a blind flange, and a check valve with flow through the valve secured. The 4 hour4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months Completion Time is acceptable,fs'ince i had G 3u)pA) e drywell aesign oypass seanage A/Vk of 0.9 f t were exceeded, ACTIONS NOTE 4 will ensure aooronriata anearum+4u- eh 3re innla=antedf The Completion Time is reasonable, considering the time required to isolate the penetration, and the probability of a DBA, which requires the drywell isolation valve (s) to close, occurring during this short time is very low.

C.1 and C.2 If any Required Action and associated Completion Time cannot be met, the plant must be placed in a MODE in which the LC0 does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and to MODE 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

(continued)

GRAND GULF B 3.6-117 Revision No. 0

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GNRO-95/00128 and R80-42193 i Attachment 3 Page 23 l l

l lNSERT B 3.6-117A ,

i due to the low probability of the inoperable valves resulting in excessive drywellleakage and the 3 low probabilty of the limiting event for drywellleakage occurring during this short time frame. j l

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. GNRO 95/00138 and R8G-43193 Attachment 4 Page 1 4

I Mark-up of Affected Technical Specifications and Bases )

1 Drywell Leak Rate Testing Requirements River Bend Station 6

4 River Band

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GNRO-9W128 and RBG-42193 Attachment 4 Page3 g) 3.6.5.1 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.5.1.'3 Verify bypass leakage is less than or N ,'

equal to the bypass leakage limit.

57 Mowever, during the first unit startup f-Cos.fi )

following bypass leakage testing / 3,4 -Q / A ,

performed in accordance with this SR, the k acceptance criterion is s 10% of the drywell bypass leakage limit.

SR 3.6,5.1.4 Visually inspect the exposed accessible Once prior to interior and exterior surfaces of the performance of drywell. each Type A test required by SR 3.6.1.1.1 Tn5stk u- c, i 6 4

RIVER BEND 3.6-61 Amendment No. 81

.- _.~ _ . _ . _ . . _ _ _ . . __. . . _ _ . . _ . _ . . _ _. . _ _ ___. . _ . . _

l l

GNRO-96/00128 and reg 42193 Attachment 4 Page 3 1

l l lNSERT 3.6 61 A l

24 months following 2 )

consecutive tests with j

, bypass leakage greater. !

l than the bypass leakage

! limit until 2 consecutive -l h tests are less than or equal to the bypass leakage limit M

48 months.'ollowing a test with bypass leakage greater than the bypass leakage !!mit M

........... .. . N O T E--------------

SR 3.0.2 is not applicable for extentions > 12 months.

j 120 months INSERT 3.6-618 SR 3.6.5.1.5 Verify seal leakage rate when the gap between Once within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months the door seats is pressurized to 2 3 psid. after each drywell air lock door closing SR 3.6.5.1.6 Verify drywell air lock leakage by performing an 24 months air lock barrelleakage test at 2 3 psid.

River Bend

GNR49%o128 and RBG-42193 Page 4 Attachant 4 Drywell Air Lock 3.6.5.2 3.6 CONTAINHENT SYSTEMS 3.6.5.2 Drywell Air Lock l LCO 3.6.5.2 The drywell air lock shall be OPERABLE.

APPLICABILITY: MODES 1, 2, and 3.

ACTIONS

NOTE-------------------------------------

1. Entry and exit is permissible to perform repairs of the affected air lock components. l

2. E er appli ble Cond ions an equired etionbfLCO 6.5.1, "Dr 11," wh air lac leakage sults i 1 dr 11 bypas eakage te accep ce crit ia. exceec%over

...........__...__ ............__...__.............__..........~...............

CONDITION REQUIRED ACTION COMPLETION TIME a 1

A. One drywell air lock ------------NOTES------------

door inoperable. 1. Required Actions A.1, A.2, and A.3 are not applicable if both doors in the air lock are inoperable and Condition C is entered.

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

A.1 Verify the OPERABLE 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months door is closed.

AND (continued)

RIVER BEND 3.6-62 Amendment No. 81

GNRO-95/00928 and RBG 42193 Attachment 4 Page5 Drywel1 Air Lock 3.6.5.2 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C. Drywell air lock C.1 nitiate a iontoD (....md; J;'.D L inoperable for reasons e luate dry 11 J other than Condition A ove 11 leakag ate or B. per L 3.6.5.1, "Drywel " using current a lock tes , ,

results. l l A l

2 Verify a door is I hour closed.

AND l C. Restore air lock to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months OPERABLE status.

i D. Required Action and 0.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months l associated Completion Time not met. AND D.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months RIVER BEND 3.6-64 Amendment No. 81

GNRO-9s/00128 and RBG42193 Page 6 Attachment 4 Drywell Air Lock 3.6.5.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY 9

}

e -

N to SR 3.6.5.2.1 Verify seal leakage rate b CG- M Once within 72 j when the gap between the door seaFs is hours after

- _.__ - pressurized to a 3.0 psid. each drywell 1 3].4 -'I -'

air lock door closing d

SR 3.6.5.2.2 Verify drywell air lock seal air flask 7 days j pressure is a 75 psig.

i

SR 3.6.5.2.3 ------------------NOTE-------------------

Only required to be performed upon entry into drywell.

24 Verify only one door in the drywell air M months lock can be opened at a time.

O

- N. S . 5. @ 'l.

-----NOTES- --------- ----

n inoper le air loc oor doe not M{ 1 1 validate e previous uccessfu

M pe ormance o the overal air loc

** leak e test. ;

J LC O t

3'g ,5, l 2. Prior to erforman of the ov all test at n .0 psid, e airlock all

% d to 19.2 sid.

______\pressuri__________ ...______ __________

, qq Verif drrwell air lock leakage W months rat er = - ^ by performing an Nu* * '

l g" air lock leakage test at 2 3.0 L.__

(continued)

RIVER BEND 3.6-65 Amendment No. 81

GNRO-95/00128 and RBG-42193

^"**' " "'d "*'* 7 Drywell Isolation Valves 3.6.5.3 3.6 CONTAINMENT SYSTEMS 3.6.5.3 Drywell Isolation Valves LC0 3.6.5.3 Each Drywell Isolation Valve shall be OPERABLE.

APPLICABILITY: MODES 1, 2, and 3.

ACTIONS

....___.__...................--------NOTES------------------------------------

1. Penetration flow paths, except for the 24 inch purge valve penetration flow path, may be unisolated intermittently under administrative controls.

2. Separate Condition entry is allowed for each penetration flow path.

3. Enter applicable Conditions and Required Actions for systems made inoperable by Drywell Isolation Valves.

4-. er app ble Condit s and Requ Actions o C0 3.6. . ,

"Dr 11," wh drywell is ion valve kage resul in exce ing overal drywell ss laak=na te -eanta criteria.

CONDITION REQUIRED ACTION COMPLETION TIME ;

A. One or more A.1 Isolate the affected 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months penetration flow paths penetration flow path with one drywell by use of at least isolation valve one closed and inoperable. de-activated automatic valve, closed manual valve, blind flange, or check valve with flow I through the valve j secured. !

AND (continued)

RIVER BEND 3.6-67 Amendment No. 81

[

4 GNRO-95/00128 and RBG43193 Attachment 4 Page 8 Drywel1 i

f B 3.6.5.1 l

BASES 4

SURVEILLANCE SR 3.6.5.1.3 REQUIREMENTS (continued) . The analyses in Reference 1 are based on a maximum drywell bypass leakage. This Surveillance ensures that the actual drywell bypass leakage is less than orgqual to thq '

acceptable AME design value of 1.0 ft are ni b S7"Ry:r.m. As left drywell bypass leakage, prior to tne first startup after performing a required drywell bypass leakage test, is required to be s 10% of the drywell bypass leakage limit. At all other times between required drywell leakage rate tests, the acceptance criteria is based on design AME. ' At the design ANE the containment temperature and pressurization response are bounded by the assumptions of the safety analysis J.ne leakage test i h rperformed every Is mondis, sunMs ent with the difficulty ch.

_ performing the test, risk of high radiation exposure, and I the remote possibility that a component failure that is not '

Q: j n Rr 4 identified by some other drywell or primary containment SR might occur. Operating experience has shown that these 6'3.L-/Q oA -

components usually pass)t" surveillance when performed at J tthe 18 month Frecuencv. yerefore, the Frequency was concluded to be acceptable from a reliability standpoint.

4 SR 3.6.5.1.4 The exposed acesssible drywell interior and exterior i surfaces are inspected to ensure there are no apparent physical defects that would prevent the drywell from performing its intended function. This SR ensures that drywell structural integrity is maintained. The Frequency was chosen so that the interior and exterior surfaces of the drywell can be inspected in conjunction with the inspections of the primary containment required by 10 CFR 50, Appendix J Nhfg ] (Ref. 2). Due to the passive nature of the drywell structure, the specified Frequency is sufficient to identify

'3,G 12OO component degradation that may affect drywell structural ,

y integrity.

REFERENCES 1. USAR, Chapter 6 and Chapter 15.

RIVER BEND B 3.6-120 Revision No. 0

GNRo-95/00138 and RBG-43193 Attachrnent 4 Page 9 3

INSERT B 3.6-120A This Surveillance is performed at least once every 10 years on a performance based frequency.

The Frequency is consistent with the difficulty of performing the test, risk of high radiation exposure, and the remote possibility that sufficient component failures will occur such that the drywell bypass leakage limit will be exceeded. if during the performance of this required Surveillance the drywell bypass leakage rate is greater than the drywell bypass leakage limit the Surveillance Frequency is increased to every 48 months. If during the performance of the subsequent consecutive Surveillance the drywell bypass leakage rate is less than or equal to the drywell bypass leakage limit the 10 year Frequency may be resumed, if during the performance of two consecutive Surveillances the drywell bypass leakage is greater than the drywell bypass leakags limit the Surveillance Frequency is increased to at least once every 24 months. The 24 month Frequency is maintained until during the performance of two consecutive Surveillances the drywell bypass leakage rate is less than or equal to the drywell bypass leakage limit, at which time the 10 year Frequency may be resumed. For two Surveillances to be considered consecutive the Surveillances must be performed at least 12 months apart.

Since the Frequency is performance based, INSERT B 3.6-120B SR 3.6.5.1.5 This SR requires a test be performed to verify sealleakage of the drywell air lock doors at 3.0 psid. An administrative seai leakage rate limit has been estcblished in plant procedures to ensure the integrity of the seals. The Surveillance is only required to be performed once within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after each closing. The Frequency of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months is based on operating experience.

SR 3.6.5.1.6 This SR requires a test to be performed to verify air lock leakage of the drywell air lock at pressures 2 3 psid. Prior to the performance of this test the airlock is pressurized to 2 19.2 psid. The 24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for violating the drywell boundary. Operating experience has shown these components usually pass the Surveillance and requires the SR to be performed once each refueling cycle. Therefore, the Frequency was concluded to be acceptable from a reliability standpoint.

River Bend

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)

4 GNRO-95/00138 and RBG-43193 Attachment 4 Page 10 Drywell Air Lock B 3.6.5.2 BASES 4

BACKGROUND 6dr eM1ock do not need to meet the requ rements3 l (continued) ! of 10 CF 50, Appendix J ef. 1), sinc it is not p t of j e primar ontainment lea e boundary, owever, i is 1

'L for the p dent to sp ify a leakage r e requireme

(' dr 11 air loc A seal leakag ate limit o s 4.05 sc a.nd a air lock o all leakage rat limit of s .85 scfh, \

at 3.0 sid, have be established to ure the i e rity Qfthes 1s. , -

APPLICABLE Analytical' methods and assumptions involving the drywell are SAFETY ANALYSES presented in Reference 2. The safety analyses assume that for a high energy line break inside the drywell, the steam

. is directed to the suppression pool through the horizontal vents where it is condensed. Since the drywell air lock is i part of the drywell pressure boundary, its design and l maintenance are essential to support drywell OPERABILITY, which assures that the safety analyses are met.

The drywell air lock satisfies Criterion 3 of the NRC Policy Statement.

LCO The drywell air lock forms part of the drywell pressure boundary. The air lock safety function assures that steam

- resulting from a DBA is directed to the suppression pool.

Thus, the air lock's structural integrity is essential to the su.cessful mitigation of such an event.

The air lock is required to be OPERABLE. For the air lock to be considered OPERABLE, the air lock interlock mechanism must be OPERABLEr =ii ivd 190* ""** ha "4+hi" %

and both air lock doors must be OPERABLE. The interlockW allows only one air lock door of an air lock to be opened at one time. This provision ensures that a gross breach of the

_ drywell does not exist when the drywell is required to be 3g OPERABLE.

j 3 kIRRA Closure of a single door in the air lock is necessary to support drywell OPERABILITY following postulated events.

Nevertheless, both doors are kept closed when the air lock is not being used for entry into and exit from the drywell.

(continued) j RIVER BEND B 3.6-122 Revision No. O i

~

GNRO-95/00128 and RBG-43193

- Attachment 4 Page 11 INSERT B 3.6-122A Air lock leakage is excluded from this Specification. The air lock leakage rate is part of the drywell leakage rate and is controlled as part of OPERABILITY of the drywell in LCO 3.6.5.1, "Drywell".

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Drywell Air Lock l

8 3.6.5.2 i

}

' BASES (continued) ,

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of j radioactive material to the primary containment. In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, the drywell air lock is not i required to be OPERABLE in MODES 4 and 5.

ACTIONS The ACTIONS are modified by Note I which that allows entry I and exit to perform repairs on the affected air lock l component. If the outer door is inoperable, then it may be easily accessed to repair. If the inner door is inoperable, l however, then there is a short time during which the drywell boundary is not intact (during access through the outer i door). The ability to open the OPERABLE door, even if it J means the drywell boundary is temporarily not intact, is !

acceptable due to the low probability of an event that could pressurize the drywell during the short time in which the OPERABLE door is expected to be open. The OPERABLE door must be immediately closed after each entry and exit.

dheACTI S are modi d by a sec Note, w h ensures ropriat *emedial ac ns are ta when nec sary.

N Pu uant to %Q 3.0.6, AC dryw 1 is exceh ng its by S are no s leakage equired e n if the mit. The fore, 1

the No is addec require IONS for L 3.6.5.1 be l 3

aken in his event A.l. A.2. and A.3 With one drywell air lock door inoperable, the OPERABLE door must be verified closed (Required Action A.1). This ensures that a leak tight drywell barrier is maintained by the use 4 of an OPERABLE air lock door. This action must be completed

, within I hour. The 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Completion Time is consistent with the ACTIONS of LCO 3.6.5.1, "Drywell," which requires that the drywell be restored to OPERABLE status within I hour.

In addition, the air lock penetration must be isolated by locking closed the OPERABLE air lock door within the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Completion Time. The Completion Time is considered reasonable for locking the OPERABLE air lock door, considering that the OPERABLE door is being maintained closed. !

(continued)

RIVER BEND B 3.6-123 Revision No. 0

\

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GNRO-95/00138 and RBG-43193 '

^""*"" * '8 l Drywell Air Lock B 3.6.5.2 i .

BASES I l

ACTIONS B.1. B.2. and B.3 (continued) l drywell under the control of a dedicated individual j stationed at the air lock to ensure that only one door is opened at a time.

C.lt D R v s-l With. the air lock inoperable for ransons other than those __

describedinConditionAorB,(Requi Actron C.1 quires faction to be diately ini m ted to e luate drywel ypass leakage ing current a- lock te results. A N aluation is acc table, since diately declare he drywell in erable i both doors is over conservativ te

, i an a lock have fail a seal test r the ove 11 air loc

}1eakag is not within 1 its. In man instance (e.g.,only one seal er door has fai d),drywell mains OP BLE, yeti

+

. only 1 hou (per LCO 3.6.5. would be p vided to store

the air lock or to OPERABL tatus prio o requir ga plant shutdown. In addition, en with bot oors fai 'ng the seal test, th overall drywe leakage ra cansti%b within limity kequiredActionC.'requiresthatonedoorinthedrywell air lock must be Terified to be closed. This Required Action must be completed within the 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Completion Time.

This specified time period is consistent with the ACTIONS of 1

LCO 3.6.5.1, which requires that the drywell be restored to l OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months .

1 Additionally, the air lock must be restored to OPERABLE '

' status within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . The 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Completion Time is reasonable for restoring an inoperable air lock to OPERABLE status, considering that at least one door is maintained i closed in the air lock.

D.1 and 0.2 If the inoperable drywell air lock cannot be restored to OPERABLE status within the required Completion Time, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to

. at least MODE 3 within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and to MODE 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

(continued)

RIVER BEND B 3.6-125 Revision No. O

GNRO 95/00128 and R8G43193

"" # * Drywell Air Lock 8 3.6.5.2 BASES (continued) !

SURVEILLANCE SR 3.6.5.2.1 _

' ~

REQUIREMENTS This SR requires a test be~ performed to verify seal leakage .

mcmb of the drywell air lock doors at 3.0 psid. A seal leakage

-N rate limit of s 4.05 scfh has been established to ensure the

( g g-Ido integrity of the seals. The Surveillance is only required

~

to be performed once within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after each closing.

(The Frequency of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months is based on operating experience. _

-- SR 3.6.5.2.2 Every 7 days the drywell air lock seal air flask pressure is verified to be a: 75 psig to ensure that the seal system remains viable. It must be checked because it could bleed down during or following access through the air lock, which 1 occurs regularly. The 7 day Frequency has been shown to be acceptable, based on operating experience, and is considered 1 adequate in view of the other indications to the plant '

operations personnel that the seal air flask pressure is low.

SR 3.6.5.2.3 l

The air lock door interlock is designed to prevent I simultaneous opening of both doors in the air lock. Since I both the inner and outer doors of the air lock are designed to withstand the maximum expected post accident drywell pressure, closure of either door will support drywell OPERABILITY. Thus, the door interlock feature supports drywell OPERABILITY while the air lock is being used for personnel transit in and out of the drywell. Periodic j testing and preventive maintenance of this interlock '

demonstrates that the interlock will function as designed and that simultaneous inner and outer door opening will not inadvertently occur. Due to the nature of this interlock, and given that the interlock mechanism is only challenced -

24 I when a drywell air lock door is openecfInis ;est i onTy required to be performed once every't$5 months. The month Frequency is based on the need to perform this Surveillance under the reduced reactivity conditions that apply during a plant outage and the potential for violating the drywell boundary. Operating experience has _shown these components _

usually pass the Surveillance G p, ... ;; . Ge w x4 (continued)

RIVER BEND B 3.6-126 Revision No. 0

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GNRO 95/00128 and RBG 43193 Attachment 4 Page 15 Drywell Air Lock 2

B 3.6.5.2 BASES

! SURVEILLANCE' SR 3.6.5.2.3 (continued)

REQUIREMENT _S _

! Q + Q Frequency is based on the refueling cycle. .

Therefore, the Frequency was concluded to be acceptable from l i a reliability standpoint.

l The Surveillance is modified by a Note requiring the

}

Surveillance to be performed only upon entry into the -

drywell. l l l SR 3.6.5.2.4

{

iT s SR requires a test to e performed to verify stverall

, air ock leakage of the dryw 1 air lock at 3.0 psi The

j. I18 mo th Frequency is based on he need to perform th s r .Survei ance under the condition that apply during a ant i TV7sw.b outage a d the potential for viola ng the drywell boun ry. ,

j % Operating xperience has shown these omponents usually p s 1 1 the Survei nce when performed at the 8 month Frequency, l

%t.d3MID i which is bas on the refueling cycle.

Frequency was herefore, the neluded to be acceptable om a reliability i I standpoint.

T s SR has been ified by two Notes. The f st Note

l in cates that an in erable air lock door does t

! .inva date the previo successful performance of overall i air lo leakage test. his is considered reasonab , since 1 either r lock door is c able of providing a fissio l product b rier in the eve of a DBA.

i

) The Surveill ce is modified a Note requiring the air lock to be pr surized to 19.2 id prior to performance of the overall ai lock leakage tes The 19.2 psid j differential pr sure is the assu peak drywell pressure

expected from th accident analysis. Since the drywell

! pressure rapidly turns to a steady state maximum

{ f differential press re of 3.0 psid (due to suppression pool l vent clearing), the leakage is allowed to be measured at s press >

1

! SR 3.6.5.2.5 i

l This SR ensures that the drywell air lock seal pneumatic

! system pressure does not decay at an unacceptable rate. The air lock seal will support drywell OPERABILITY down to a i pneumatic pressure of 75 psig. Since the air lock seal air 1

(continued) l RIVER BEND B 3.6-127 Revision No. 0 i

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1 GNRO-95/00128 and R8G-42193

+

, Attachment 4 Page is Drywell Isolation Valves B 3.6.5.3 BASES BACKGROUND The drywell purge isolation valves fail closed on loss of (continued) instrument air or power. The drywell purge isolation valves are fast closing valves (approximately 4 seconds).

APPLICABLE This LCO is intended to ensure that releases from the core SAFETY ANALYSES do not bypass the suppression pool so that the pressure suppression capability of the drywell.is maintained.

Therefore, as part of the drywell boundary, drywell isolation valve OPERABILITY minimizes drywell bypass :

leakage. Therefore, the safety analysis of any event requiring isolation of the drywell is applicable to this LCO.

The limiting DBA resulting in a release of steam, water, or radioactive material within the drywell is a LOCA. In the analysis for this accident, it is assumed that drywell isolation valves either are closed or function to close within the required isolation time following event initiation.

The drywell isolation valves and drywell purge isolation valves satisfy Criterion 3 of the NRC Policy Statement. l l

LC0 The drywell isolation valve safety function is to form a l part of the drywell boundary. ;

The power operated drywell isolation valves are required to have isolation times within limits. Power operated automatic drywell isolation valves are also required to actuate on an automatic isolation signal. Additionally,

' drywell purge valves are r'equired to be closed.

F I

6 3.6-I3*A The normally closed isolation valves or blind flanges are t

a considered OPERABLE when, as applicable, manual valves are closed or opened in accordance with applicable administrative controls, automatic valves are de-activated i and secured in their closed position, check valves with flow through the valve secured, or blind flanges are in place.

The valves covered by this LC0 are included (with their .

associated stroke time, if applicable, for automatic valves) I in Reference 2. ,

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(continued)

RIVER BEND B 3.6-130 Revision No. O

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GNRO-95/00128 t,nd RBG-42193 Attachrnent 4 Page 17 INSERT B 3.8-130A Drywell isolation valve leakage is excluded from this Specification. The drywell isolation valve leakage rates are part of the drywellleakage rate and are controlled as part of OPERABILITY of the drywell in LCO 3.6.5.1, "Drywell".

River Bend

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GNRO 9&o0138 and R8G43193 ent 4 Page 18 Drywell isolation Valves

. B 3.6.5.3 BASES (continued)

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of radioactive material to the primary containment. In MODES 4 and 5, the probability and consequences of these events are j reduced due to the pressure and temperature limitations in '

these MODES. Therefore, the drywell isolation valves are not required to be OPERABLE in MODES 4 and 5.

l ACTIONS The ACTIONS are modified by four Notes. The first Note l allows penetration flow paths, except for the 24 inch purge valve penetration flow paths, to be unisolated intermittently under administrative controls. These controls consist of stationing a dedicated operator, who is ,

in continuous communication with the control room, at the l controls of the valve. In this way, the penetration can'be l rapidly isolated when a need for drywell isolation is indicated.

The second Note provides clarification that for the purpose of this LCO separate Condition entry is allowed for each penetration flow path. This is acceptable, since the Required Actions for each Condition provide appropriate compensatory actions for each inoperable drywell isolation valve. Complying with the Required Actions may allow for ;

continued operation, and subsequent inoperable drywell ;

isolation valves are governed by. subsequent Condition entry and application of associated Required Actions.

The third Note requires the OPERABILITY of affected systems to be evaluated when a drywell isolation valve'is inoperable. This ensures appropriate remedial actions are

.taken, if necessary, if the affected system (s) are rendered inoperable by an inoperable drywell isolation valve.

e four Note ensur appropria remedial a ions are kan when drywell ass leaka limits are ceeded.

P uant to L .0.6, th ACTIONS not requi d even when e associa LCO is n met. The fore, Note 3 7 and 4 added to uire the oper acti are take T -

A.1 and A.2 With one or more penetration flow paths with one drywell isolation valve inoperable, the affected penetration flow path must be isolated. The method of isolation must include the use of at least one isolation barrier that cannot be adversely affected by a single active failure.

(continued)

RIVER BEND B 3.6-131 Revision No. O

i l GNRO-95/00138 and RBG-43193 i ' Attachment 4 Page 19 OryWell Isolation Valves

B 3.6.5.3 L ,

BASES j

! ACTIONS A.1 and A.2 (continued) i

! Isolation barriers that meet this criterion are a closed and de-activated automatic valve, a closed manual valve, a blind il flange, and a check valve with flow through the valve secured. In this condition, the remaining OPERABLE drywell isolation valve is adequate to perform the isolation

function. However, the overall reliability is reduced 1 -because a single failure in the OPERABLE drywell isolation i valve could result in a loss of drywell isolation. The _

! 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months Completioq Tinth accentable nce the d 1

! e by ss leage A//li o%0 frt we exce d, te will emure appro nd a+ e y_ 'vativ f'Imd \

! TIO ctio

3 ar impi !mente . In adattton, t1e Completion Time is'

] g ' reasonab' e, considering the time required to isolate the

6 3,4-132 Aj penetration and the relative importance of supporting drywell OPERABILITY during MODES 1, 2, and 3.

l For affected penetration flow paths that have been isolated in accordance with Required Action A.1, the affected i penetrations must be verified to be isolated on a periodic 1 basis. This is necessary to ensure that drywell i penetrations that are required to be isolated following an i accident, and are no longer capable of being automatically isolated, will be isolated should an event occur. This Required Action does not require any testing or device ,

manipulation; rather, it involves verification that those )

devices outside drywell and capable of potentially being l mispositioned are in the correct position. Since these devices are inside primary containment, the time period specified as " prior to entering MODE 2 or 3 from MODE 4, if not performed within the previous 92 days," is based on engineering judgment and is considered reasonable in view of the inaccessibility of the devices and other administrative controls that will ensure that misalignment is an unlikely possibility. Also, this Completion Time is consistent with the Completion Time specified for PCIVs in LCO 3.6.1.3,

" Primary Containment Isolation Valves (PCIVs)."

Required Action A.2 is modified by a Note that applies to I isolation devices located in high radiation areas and allows l them to be verified by use of administrative controls.

Allowing verification by administrative controls is considered acceptable, since access to these areas is typically restricted. Therefore, the probability of misalignment, once they have been verified to be in the proper position, is low.

(continued)

RIVER BEND B 3.6-132 Revision No. O I

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GNRO-95/00128 and RBG-43193 Attachment 4 Page 20 INSERT B 3.8-132A due to the low probability of the inoperable valve resulting in excessive drywell leakage and the low probability of the limiting event for drywell leakage occurring during this short time frame.

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GNRO-95/00128 and RSG-42193

Page 21 Attachment 4 Drywell Isolation Valves B 3.6.5.3 BASES ACTIONS B.1 With one or more penetration flow paths with two drywell isolation valves inoperable, the affected penetration flow path must be isolated. The method of isolation must include !

the use of at least one isolation barrier that cannot be i adversely affected by a single active failure. Isolation .

barriers that meet this criterion are a closed and )

de-activated automatic valve, a clused manual valve, a blind i flange, and a check valve with flow through the valve 1 sacured. "he 4 hour4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months Complntinn Time is nece) tabla n if It e dr l' d n bypa A eakage o" N ft' e l _, %,ex ded, CTION ote 4 wi nsure opri

.Lo$,d cons vativ Naction are imal ted/The Completion Time is reasonab' e, considering the time required to isolate the 1g y g._gg penetration, and the probability of a DBA, which requires i

i the drywell isolation valves to close, occurring during this i short time is very low.

C.1 and C.2 If any Required Action and associated Completion Time cannot be met, the plant must be placed in a MODE in which the LC0 does not apply. To achieve this status, the plant must be

, brought to at least MODE 3 within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and to MODE 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . .The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

SURVEILLANCE SR 3.6.5.3.1 REQUIREMENTS

. Each 24 inch drywell purge isolation valve is required to be verified sealed closed at 31 day intervals. This Surveillance is required since the drywell purge isolation valves are not qualified to close under accident conditions.

This SR is designed to ensure that a gross breach of drywell is not caused by an inadvertent or spurious drywell purge isolation valve opening. Detailed analysis of these 24 inch drywell purge valves failed to conclusively demonstrate their ability to close during a LOCA in time to support drywell OPERABILITY. Therefore, these valves are required to be in sealed closed position during MODES 1, 2, and 3.

These 24 inch drywell purge valves that are sealed closed must have motive power to the valve operator removed. This (continued)

RIVER BEND B 3.6-133 Revision No. O

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GNRO-95/00138 and RBG-42193 Attachment 4 Pag 332 INSERT B 3.6-133A l

due to the low probability of the inoperable valves resulting in excessive drywell leakage and the I low probability of the limiting event for drywell leakage occurring during this short time frame. !

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GNRo-95/00128 and RBG-42193 Attachment 5 page 1 of 7 Staff Questions Concoming the Proposed Changes

.1. Is it possible to demonstrate that loss of seals to all electricalpenetrations passing through the drywell would not cause A/k to be exceeded?

A typical GGNS drywell electrical penetration is shown on Figure 3.8-62 of the GGNS UFSAR. To meet the objectives of leaktightness, each electrical penetration consists of a steel conduit, not larger than 6 inches in diameter, with a sealing condulet. After cable installation, the condulet chamber is filled with a sealing compound (very similar in practice to portland cement) which solidifies around the cable. The sealant is designed to last for the life of the plant and to resist the highest pressure and temperature which could be experienced in the drywell. The conduit is pre-bent and embedded into the drywell concrete wall. Any failure mechanism is more likely to cause seal degradation (with the seal material remaining in the conduit) rather than a complete loss of the seal. A loss of multiple seals or degradation of multiple seals is of low probability.

There are thirty six 4 inch electrical penetrations and four 6 inch penetrations. The effective flow area would be around an A /Vk of 4 ft* considering the failure of all of the penetrations, if all of the penetrations are empty. But this is an unrealistic assumption. The electrical penetrations as a class are being used and are at least partially filled with cable. It is reasonable to assume that flow through the electrical penetrations will be greatly restricted by cabling in the penetration and the concrete like sealant. With the reasonable assumption that any failure of the sealing substance leaves the conduit about 75% blocked, the primary containment should not be expected to fail due to the failure of the electrical penetration sealant.

As evidenced by the continuous successful drywell bypass tests at GGNS and RBS since the beginning of plant operation, the drywell electrical penetrations have been demonstrated to be very reliable in performing the drywell isolation function. This proven reliability of the electrical penetrations is consistent with the Appendix J Option B 10 year required test interval of electrical penetrations to support the containment isolation function (Type B testing).

2. Verify thatposition of alldrywellisolation valves is monitoredin the controlroom.

If not all, which drywellisolation valves are not monitoredin the controlroom? If valves are not completely closed, will they indicate open?

The automatic isolation valves and remote manual isolation valves have position indication in the control room. Manual isolation valves and most check valves do not. Isolation valves with position indication that are not closed would either have an open position indication (indicating that the valve is full open) or a dual indication (indicating that the valve is somewhere between full closed and full open). Valve position is required to be checked by LCO 3.6.5.3. The controls over the drywell i

GNRo-95/oo128 and RBG-42193 Attachment 5 page 2 of 7 isolation valve position are the same as the controls for similar valves in the primary containment.

See the table of GGNS penetrations potentially without valve position indication below. Also, not shown is the one ILRT penetration which is blank flanged.

Type of lsolation Penetration size inches dia.

CRD to Recirc. Pump A Seals Stop checks .75 Standby Liquid Control 3 stop checks in-line 1.5 with the explosive

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valves i

l Condensate Flush Conn. Locked Closed Manual 4 j Upper Containment Pool Drain Locked Closed Manual 3 CRD to Recire. Pump B Seals Stop Checks .75 )

l Service Air Stop Check and .75 i Locked Closed Manual Instrument Air Stop Check and .75 Locked Closed Manual Cont. Leak Rate Test Inst. Locked Closed Manual 1 Attachment 2 of the change request identifies the A /Vk of a 10 inch line (Drywell post LOCA vacuum relief subsystem A) was 0.255 ft2 . Making the conservative assumption that the A /Vk changes linearly as valve size decreases, the effective A /

Yk of all of these penetrations failing full open is less than the effective A /Vk of a 10 inch line. As discussed in the submittal, failure of four 10 inch lines do not result in primary containment failure.

3. Can on-line monitoring capability of the drywellleakage rate be provided?

An on-line monitoring program would require some amount of drywell pressurization.

Drywell pressurization during operation could cause an operating transient or a challenge to safety systems such as RPS and ECCS systems (GGNS RPS actuates at 1.23 psig drywell pressure and GGNS ECCS at 1.39 psig drywell pressure). We do not believe the test would provide a substantial safety benefit and would in effect introduce an unwarranted potential challenge to the plant.

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GNRo-95/00128 and RBG-42193 Attachment 5 page 3 of 7 4

Additionally, the present potential methods of monitoring drywell bypass leakage do not provide any'reai assurance of drywellleaktightness. For example:

At GGNS the drywell purge compressor surveillance results in the drywell being pressurized such that the pressure must be relieved to prevent a reactor scram.

Another source of drywell pressurization during operation is the instrument air system. If the purge compressors no longer result in the same pressurization of the "

drywell is it due to a change in drywell leakage, a change in instrument air leakage in to the drywell, or a combination of factors? Or if the drywell pressurization transient caused by the purge compressors does not change how can you be assured that by drywell leakage and the instrument air leakage have not changed but are canceling each other out with respect to drywell pressurization?

4. In March 1983 a drywellbypass leakage test failed at Grand Gulf on the first attempt. The failure was attributed to two electricalpenetrations. Describe the circumstances that led to the failure and explain why the failure could not take place now. ,

l The following is the discussion of initial test failure from the surveillance test !

package: ;

"Drvwell Bvoans Leakana Rate Test 06-ME-1 M104-0003 i Notes of As-Found Data

The initial attempt to pressurize the drywell indicated larger than expected leakage.

Subsequent walkdowns indicated two problem areas. The closing of a partially open vent valve on the vendor supplied compressor skids corrected the ability of the 4

test to supply rated air flow. The temporary sealing of two open electrical conduits eliminated the other major leakage path. These two conduits were open as a result i of ongoing construction activities and were scheduled to be closed when manpower permitted. The temporary sealing of these conduits during the course of the initial drywell pressurization does not affect the validity of the As-Found data as these conduits were spares which had been sealed prior to the start of recent construction activities which opened them. These conduits will be permanently sealed prior to '

the start of nuclear heatup.

The leakage path through these two open conduits does not indicate a degradation of drywellintegrity as the leakage was the result of construction activities and not the result of degradation of the conduit sealing compounds.

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l GNRo-96/00128 and RBG-42193 Attachment 5 page 4 of 7 i

1 As discussed above there was two problems with the test.

A. A test hookup problem with how the equipment was hooked up. Not really a

j. drywell problem.

i B. The problem that two electrical penetrations were open. It should be remembered that this was during the pre-operating license time frame. There is fewer activities occurring in the plant now and the maintenance controls are much stronger. - That the maintenance controls are now adequate is demonstrated by the successful performance of all 8 tests in the 10 years after this event.

5. How far couldpurge and vacuum relief valves be open before there would be an OPENindication in the controlroom?

The specific amount is not known. This position indication is set as close to full openiciosed as possible. Also the valves were indicating closed during the last drywell bypass test and the test passed; therefore, we know the indicated position corresponds close enough for drywell bypass requirements. Regardless, these valves receive isolation signals (LCO 3.3.6.1) and are designed to isolated when required. The use and isolation capability of these valves is discussed in the Bases Background for GGNS LCO 3.6.5.3.

"Drywell Vent and Purge System is seldom used in MODE 1, 2, or 3; therefore, the drywell purge isolation valves are seldom open during power operation.

The drywell purge isolation valves fail closed on loss of instrument air or power. The drywell purge isolation valves are fast closing valves (approximately 4 seconds).

These valves are qualified to close against the differential pressure induced by a loss of coolant accident (LOCA)."

5(a) Provide details of the calculation of the A/k values for the 10-inch vacuum relief valves and the 20-inch purge valves GGNS 10 inch UFSAR 6.2.5.1.1 discusses the effective Alk of these flowpaths. The UFSAR states:

r. The design basis for the drywell vacuum relief function is to prevent backflow over the weir wall following a postulated small break LOCA.

The vacuum relief system also serves to control rapid weir wall overflow following a postulated large break LOCA. Bounding calculations using conservative assumptions have shown that there would be no damage to safety- related equipment in the drywell above

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GNRo-95/0o128 and RBG-42193 l Attachment 5 page 5 or 7 the weir wall from drag and impact loads due to water backflow over the weir wall. Present drywell negative pressure analysis for rapid j weir wall overflow in a large break LOCA assurnes a vacuum relief i capability of Alk = 0.38 ft*, This relief capability requires a minimum l of two 10 inch drywell vacuum relief paths out of the three installed. I Drywell vacuum relief is not required to assist in hydrogen dilution or to protect the structural integrity of the drywell following a large break LOCA.

As discussed on page Attachment 2 page 9 the specific values identified in the submittal are from the calculation to support this statement.

20 inch purge GGNS has estimated that the Alk of a purge line is approximately .7 ft2 ,

Discussions with Clinton Power Station personnel indicates that they have estimated that the Alk of their 24 inch line is approximately .8 ft . Therefore, the bounding estimate of 1 ft2presented in the submittalis felt the be conservative.

5(b) Verify that the discussion on page 9/23 andpage 11/23 about the margin to containment overpressure because of open vacuum relief valves or a purge valve is based on the existing LOCA analyses reported in the UFSAR and there are no assumptions in the analyses which are different than those given in the UFSAR.

These discussions are only talking about the margin between the primary containment design pressure of 15 psi and the pressure where the primary containment would actually be expected to fail (greater than 50 psi).

6. Howis the TS required verification of closure of the 20-inch purge valves performed? Indications in controlroom? Other?

Valve closure is checked using control room position indication.

7. What are the leakage testing and closure verification requirements for the drywell equipment hatch? What assurance is there, if no drywellbypass leakage test is performed, that the drywell equipment hatch is not leaking excessively?

There is about the same assurance provided as is provided when drywell bypass testing is performed during an outage, since there is no requirement to perform the bypass test at the end of the outage. The assurance is provided by the verification of leak tightness of the drywell hatch is performed following installation at the end of the outage (GGNS and RBS). See the response to below for the TS requirements driving this test.

GNRo-96/00128 and RBG-42193 Attachment 5 page 6 of 7 Leakage testing of these seals is discussed in the GGNS UFSAR 3.8.3.1.1. These are passive dual compression seals and there is no reason to expect degradation during a cycle.

8. . Is the drywellair lock ever opened during operation in MODES 1 or 2? If so, what "

controls are there to assure that there is not excessive leakage afterit is reclosed?

Yes, a Drywell entry is performed during every startup at GGNS at approximately 5% power. At high power the Drywellis considered inaccessible due to ALARA concerns. The Bases for the Drywell Air Lock LCO (3.6.5.2) in the Background section states "The drywell air lock forms part of the drywell boundary and j provides a means for personnel access during MODES 2 and 3 during [ sic] lower ,

power phase of unit startup. ... Under normal unit operation, the drywell air lock is 1 kept sealed." Following this entry the seal leakage rate is tested in accordance with I SR TR3.6.5.2.1 (GGNS) or SR 3.6.5.2.1 (RBS).

9. There do not appear to be any requirements for the leakage rate testing of the drywell after rnodifications to the drywellstructure orpenetrations. How is this addressed?

The following is discussed in the TS Bases for SR 3.0.1:

"SR 3.0.1 establishes the requirement that SRs must be met during the MODES or i other specified conditions in the Applicability for which the requirements of the LCO

]

apply, unless otherwise specified in the individual SRs. This Specification is to l ensure that Surveillances are performed to verify the OPERABILITY of systems and components, and that variables are within specified limits. Failure to meet a Surveillance within the specified Frequency, in accordance with SR 3.0.2, constitutes a failure to meet an LCO.

Systems and components are assumed to be OPERABLE when the associated SRs have been met. Nothing in this Specification, however, is to be construed as implying that systems or components are OPERABLE when:

a. The systems or components are known to be inoperable, although still meeting the SRs; or

b. The requirements of the Surveillance (s) are known to be not met between required Surveillance performances."

The Bases goes on to state:

"Upon completion of maintenance, eppropriate post meintenance testing is required to declare equipment OPERABLE. This includes ensuring applicable Surveillances are not failed and their most recent performance is in accordance with SR 3.0.2."

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GNRO-95/OO128 and RBG-42193 i Attachment 5 page 7 of 7 These Bases describe the SR 3.0.2 requirement that any time maintenance has been performed which could result in required Surveillances not being met that

appropriate post maintenance testing must be performed.

Note: GGNS SR TR3.6.5.2.4 documents specific testing required following a )

specific maintenance activity. This requirement was relocated from the TS i as part of the improved Technical Specification implementation.

10. a. The results of a calculation showing that all vacuum breakers may be left open at RBS without exceeding the drywellbypass limit based on the analysis given in the UFSAR.

River Bend does not have vacuum breakers, its hydrogen mixing system has j 6 inch valves.

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b. The results of a calculation at RBS showing that one ourge valve may be open in addition to bypass leakage at the TS limit without exceeding the i containment failure pressure. j RBS has 24 inch purge valves; therefore, the Alk should be consistent with GGNS and Clinton Power Station and the 1 ft2 presented in the submittal should be conservative.

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ML20094M800

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