Text

Bryon, Units 1 and 2, License Amendment Request to Revise Technical Specifications Section 3.7.2, Main Steam Isolation Valves (Msivs).
	ML13235A095
Person / Time
Site:	Byron, Braidwood
Issue date:	08/21/2013
From:	Gullott D; Exelon Generation Co
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	RS-13-175
	Download: ML13235A095 (40)
	v • d • e

1 2000 Office CE J E RS-13-175 10 CFR 50.90 August 21, 2013 U. S. Nuclear NuclearRegulatory Regulatory Commission Commission ATIN: Document Control Desk ATTN: Desk Washington, DC Washington, DC 20555-0001 20555-0001 Braidwood Station, Units Units 11 and and 22 Facility Operating License Nos. NPF-72 and NPF-77 Facility NRC Docket Nos. STN 50-456 and STN 50-457 Byron Station, Byron Station, Units Units 1 and 2 Facility Operating License Nos. NPF-37 and NPF-66 Facility NRC Docket Nos. STN 50-454 and STN 50-455

Subject:

License Amendment Request Request to to Revise Revise Technical Technical Specifications Specifications Section Section 3.7.2, 3.7.2, "Main Steam "Main Steam Isolation Isolation Valves Valves(MSIVs)"

(MSIVs)"

Reference:

NRC Memorandum, "Operability NRC "Operability Determination for the Callaway Plant Plant Technical Technical Specifications Requirements When One One Main Main Steam SteamIsolation Isolation Valve Valve Actuator Actuator Train is Train is Removed from Service," dated October 19, from Service," 19, 2006 2006 In accordance In accordance with with 10 CFR 50.90,50.90, "Application "Application forfor amendment amendment of of license, license, construction constructionpermit, permit, or early site permit," Exelon Generation permit," Exelon Generation Company, LLC, (EGC), requests LLC, (EGC), requests amendments amendmentsto to FacilityOperating Facility Operating License License Nos.Nos. NPF-72 NPF-72 and NPF-77 for for Braidwood Braidwood Station, Station, Units Units 11 andand 2, 2, and Facility Operating Facility Operating License License Nos. NPF-37 and and NPF-66 NPF-66 forfor Byron Byron Station, Units Units 11 and and2. 2.

The proposed proposed amendments amendmentswill will revise revise Technical Technical Specifications Specifications(TS) (TS) Section Section3.7.2, 3.7.2,"Main"Main Steam Steam Isolation Valves (MSIVs),"

(MSIVs)," to to incorporate incorporate the the MSIV MSIV actuator actuator trains trainsinto intothe theLimiting Limiting Condition Conditionforfor Operation (LCO) and provide (LCO) and provide associated associated Conditions Conditions andand Required RequiredActions.

Actions. InInaddition, addition, Surveillance Requirement Requirement (SR) (SR) 3.7.2.2 3.7.2.2isisrevised revisedtotoclearly clearlyidentify identify that thatthe theMSIV MSIV actuator actuatortrains trains are required required to be tested in in accordance accordance with with the SR.

These changes changes are areconsidered considerednecessary necessarybasedbasedononthethereferenced referencedNRC NRCstaff staffinterpretation interpretation thatthat SR 3.7.2.2 requires both actuator trains for for aa single single valve valveto tobe be surveillance surveillancetested.

tested. The NRC The NRC staff interpretation results in declaring an an MSIV MSIV inoperable with one actuatoractuator train train inoperable.

inoperable.

The Completion TimeTime ofof 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months hours forfor an an inoperable MSIVMSIV duedue toto one one inoperable actuator actuator train train is is not commensurate with with the safety significance significance of of an an inoperable actuator train.train. Therefore, Therefore, new new Conditions, Required Actions, Conditions, Actions, and Completion Times for for inoperable inoperable actuator train(s) are being being proposed.

U. S.

U. S. Nuclear Regulatory Commission August 21,2013 August 21, 2013 Page Page 2 2 This attached This attached amendment request is subdivided as follows:

Attachment 1 provides a description and evaluation of Attachment of the proposed proposed changes.

changes.

Attachments 2 and 3 provide the marked-up TS pages Attachments pages for for Braidwood Braidwood Station Station and and Byron Byron Station, respectively, Station, respectively, with with the proposed changes indicated.

Attachments 44 and Attachments and 5 provide the marked-up TS Bases Bases pages pagesforforBraidwood Braidwood Station Station and and ByronStation, Byron Station,respectively, respectively,with withthetheproposed proposedchangeschangesindicated.

indicated. The TS TS Bases pagespages are provided for information are information only only and and do do not require NRC approval.

The proposed change has been reviewed by The by the Braidwood Braidwood Station Station and and Byron Byron Station Station Plant Plant Operations Review Committees and approved by Operations by their their respective respective Nuclear Nuclear Safety Safety Review Review Boards in Boards in accordance with the requirements of the EGC EGC Quality Quality Assurance Program.

Program.

In accordance In accordance with with 10 CFR 50.91, "Notice for public comment; State State consultation," paragraph paragraph (b), EGC (b), EGC is notifying the State of Illinois of this application for for license license amendment amendment by by transmitting a copy of this letterletter and its its attachments attachments to to the the designated designated State State Official.

Official.

EGC requests EGC requests approval approval of of the the proposed proposed license license amendment amendment by by August August 21, 21, 2014.

2014. Once approved, the amendment will be be implemented implemented within within 6060 days.

days.

commitments contained There are no regulatory commitments contained in in this this letter.

letter. Should Should you you have have any any questions questions concerning this letter, letter, please contact Ms. Dwi Murray at (630) 657-3695.

I declare under penalty of perjury that the foregoing is true and and correct.

correct. Executed Executedon onthe 21 st the21st day of August August 2013.

2013.

Respectfully, Respectfully, David M. Gullott Manager - Licensing Exelon Generation Company, LLC Attachments:

Attachments:

1. Evaluation of of Proposed Proposed Changes Changes 2.

2. Proposed Technical Specifications Specifications Changes Changes for forBraidwood Braidwood Station, Station, Units Units11and and22

3. Proposed Technical Technical Specifications Specifications Changes Changes for forByron Byron Station, Station, Units Units11and and22 4.

4. Proposed Technical Specifications Specifications Bases Bases Changes for for Braidwood Braidwood Station, Station, Units Units 11 and and 22 5.

5. Proposed Proposed Technical Technical Specifications Specifications Bases Bases Changes Changes for for Byron Byron Station, Station, Units Units 11 and and 22 cc:

cc: NRC NRC Regional Regional Administrator - RegionRegion IIIIII NRC NRC Senior Senior Resident Resident Inspector Inspector - Braidwood Braidwood Station Station NRC NRC Senior Senior Resident Resident Inspector Inspector - Byron ByronStation Station Illinois Illinois Emergency Emergency Management Management Agency Agency -- Division DivisionofofNuclear NuclearSafety Safety

ATTACHMENT I ATIACHMENT1 Evaluation Eval of Proposed uation of Proposed Changes Changes

Subject:

License Amendment License Amendment Request to to Revise Technical Specifications Section 3.7.2, 3.7.2, "Main Steam "Main Steam Isolation Valves (MSIVs)"

1.0 1.0

SUMMARY

DESCRIPTION 2.0 DETAILED DESCRIPTION

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedents 4.3 No Significant Hazards Consideration Consideration 4.4 Conclusions

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

Page 11 of of 12 12

ATTACHMENT ATTACHMENT 1I Evaluation of Evaluation of Proposed Proposed Changes Changes 1.0 1.0

SUMMARY

DESCRIPTION

SUMMARY

This evaluation This evaluation supports supports aa request to to amend amend Facility Operating License Nos. Nos. NPF-72 and NPF-77 for 77 for Braidwood Braidwood Station, Station, Units Units 11 and and 2, 2, and and Facility Operating Operating License Nos. Nos. NPF-37 and NPF-66 for 66 for Byron Byron Station, Units 1 and 2. 2.

Exelon Generation Exelon Generation Company, Company, LLC, LLC, (EGC)

(EGC) proposes proposes to to revise revise Technical Technical Specifications (TS)

Section 3.7.2, Section 3.7.2, "Main "Main Steam Steam Isolation Valves (MSIVs)," to incorporate the MSIV actuator trains into the into the Limiting Limiting Condition for Operation (LCO) (LCO) and and provides provides associated associated Conditions Conditionsand and Required Actions.

Required Actions. Additionally, Additionally, Surveillance Surveillance Requirement Requirement (SR) (SR) 3.7.2.2 3.7.2.2 isis revised revised to to clearly clearly identify that identify that the the MSIV MSIV actuator actuator trains trains are are required required to to be tested tested in accordance with with the SR.

The proposed The proposed changes address an NRC staff interpretation that SR 3.7.2.2 requires both trains for aa single actuator trains single valve valve to to be tested (Reference 1). The TheNRC NRC staff staffinterpretation interpretationresults results in declaring in declaring an an MSIV inoperable when when one actuator train is inoperable. The The existing existingCompletion Completion Time of 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months for an inoperable MSIV due to one inoperable actuator train is not commensurate with with the safety significance of the condition. Therefore, Therefore, new newConditions, Conditions, Required Actions, and Completion Times Required Times for for inoperable inoperable actuator actuatortrain(s) train(s)areare being beingproposed.

proposed.

2.0 DETAILED DESCRIPTION TS 3.7.

3.7.2,2, "Main Steam Isolation Isolation Valves Valves (MSIVs)," specify operability and surveillance surveillance requirements for the MSIVs, MSIVs, which includes Conditions and Required Required Actions Actions to to be be entered entered when one or or more MSIVs are inoperable.

inoperable. Currently, TS 3.7. 3.7.2 2 does not not specifically address or reflect the twotwo independent actuator trains trains forfor one one MSIV.

MSIV. Inoperability Inoperabilityofofone oneofofthe thetwo twoactuator actuator trains trains associated with with an MSIV MSIV does doesnot notby by itself itself make makethe thevalve valveincapable incapableofofclosing closing since sincethe the remaining OPERABLE actuator remaining OPERABLE actuator train train cancan alone alone effect effect valve valve closure closure on on demand.

demand. Declaring Declaringan an MSIV MSIV inoperable inoperable and and entering entering thethe Condition(s)

Condition(s) and and Required Required Action(s) for an inoperable inoperable MSIV due only to one inoperable actuator train, train, isis unnecessarily unnecessarily restrictive.

restrictive. Therefore, Therefore, EGC EGC proposes proposes to incorporate requirements requirements specifically specifically for the MSIV MSIV actuator actuator trains trains within within TS 3.7 3.7.2

.2 such that the specification specification would include appropriate Conditions Conditions and and Required Required Actions to to address inoperable MSIV MSIVactuator actuatortrains.

trains.

Consistent Consistentwith with other other Improved Improved Standard Technical Specifications Specificationsformat, format, thethe proposed proposed Completion Times for for inoperable MSIV MSIV actuator trains are based on a hierarchy of trains are based on a hierarchy of Conditions Conditions such that shorter such that shorter Completion Times would be specified specified for increasingly degraded conditions.

for increasingly degraded conditions.

Conditions addressing addressing inoperable inoperable actuator actuator trains trains would would be specified specified first in TS 3.7.2, 3.7.2, (i.e.,

(Le., listed listed before before the Conditions that are currently in place for addressing the Conditions that are currently in place for addressinginoperability inoperabilityof ofthe theMSIVs MSIVs themselves).

themselves). Therefore, Therefore, TS TS 3.7.

3.7.22 specifies specifiesthat thatwhen whenonlyonlyan anactuator actuatortrain train isisdeclared declared inoperable, inoperable, the theapplicable applicableCondition Conditionfor forthe theinoperable inoperableactuator actuatortrain trainwould would be beentered enteredfirst.

first.

Then, Then, depending dependingon onthe thenumber numberofofactuator actuatortrains trainsthat thatare areconcurrently concurrently inoperable inoperable and and the the associated associatedRequired RequiredAction Actionforforthe theapplicable applicableCondition; Condition;or orifif the the applicable applicable Required RequiredActionAction and and Completion Completion Time Time cannot cannot bebe met, met, the theMSIV(s)

MSIV(s) associated associatedwith withthetheinoperable inoperableactuator actuator train(s) train(s) would be be declared declaredinoperable inoperableso sothat thatthetheCondition(s)

Condition(s)addressing addressing inoperability inoperabilityofofthe the MSIV(s)

MSIV(s) would would thus be be entered.

entered.

Page Page 22 of of1212

ATTACHMENT 1I ATTACHMENT Evaluation of Evaluation of Proposed Proposed Changes The following The following proposed proposed changes will will revise TS TS 3.7.2:

3.7.2:

- LCO 3.7.2 LCO 3 .7.2 is revised to include the actuator trains in the LCO.

is revised LCO. LCO 3.7.2 is revised revised to to state:

"Four MSIVs "Four MSIVs andand their associated associated actuator actuator trains trains shall shallbe be OPERABLE."

OPERABLE."

- New Conditions New Conditions A A through through E are added to TS TS 3.7.2 3.7. 2 to to address address inoperable inoperable MSIV actuator trains. The existing Conditions that existing Conditions that address address inoperable inoperable valves valves are relabeled such such thatthat those those Conditions would Conditions would become become Conditions F through II for for TS 3.7.2.

3.7.2. The proposed proposed new Conditions related Conditions related specifically specifically to to the the actuator trains trains would would address various degrees degrees or or combinations of inoperable actuator actuator trains trains asas follows:

follows:

o Condition A New Condition A would would address the the condition condition of having one MSIV actuator train inoperable (for inoperable (for aa single single valve).

valve). TheThe proposed proposed Required Required Action Action for for this this Condition Condition wouldwould require restoring the inoperable actuator require actuator train to OPERABLE OPERABLE status status within within 77 days.

days.

o Condition B would New Condition would address the the condition condition of having having two MSIV actuator trains inoperable for different valves (i.e., (Le., one actuator actuator train train inoperable inoperable forforeach each ofoftwo twoMSIVs)

MSIVs) such that the actuator trains are not in the same ESF division. division. The proposed Required The proposed Required Action for this Condition would require restoring at least one actuator train to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . hours.

oo Condition C would address the situation when two MSIV actuator trains are New Condition inoperable for different valves and the inoperable inoperable actuator actuatortrains trains are are both bothininthe thesame same ESF division.

division. The The proposed proposed Required Required Action Action for forthis this Condition Condition would would require requirerestoring restoring at least one actuator actuator train to to OPERABLE OPERABLE status status within within 2424 hours0.0281 days 0.673 hours 0.00401 weeks 9.22332e-4 months .

hours.

o New Condition D would address the situation when both actuator actuator trains for one MSIV are inoperable. The TheRequired Required Action Action proposed proposed for forthis this Condition Condition would would require requireimmediately immediately declaring the affected MSIV MSIV inoperable.

inoperable.

oo New Condition E would address the condition of having three or or more MSIV MSIV actuator actuator trains inoperable, inoperable, or or the the condition condition when, when, after afterentering entering Conditions ConditionsA, A,B, B,ororC, C,ititisis determined that the Required Action and Completion Time of of any any ofof those Conditions Conditions cannot be be met.

met. The TheRequired RequiredAction Actionfor forthis thisCondition Conditionwould wouldrequire requireimmediately immediately declaring each each affected affected MSIVMSIV inoperable.

inoperable.

- SRSR 3.7.2.2 3.7.2.2 isis revised revised toto clearly clearly identify identifythat thatthe the MSIV MSIVactuator actuatortrains trainsare arerequired requiredtotobe be tested tested in in accordance accordance with with the the SR.

SR. SR SR3.7.2.2 3.7.2.2isisrevised revisedtotostate:

state:"Verify "Verifyeach eachactuator actuatortrain train actuates actuates the MSIV MSIV to the isolation isolation position position onon anan actual actual or or simulated simulated actuation actuation signal."

signaL" Attachments Attachments 22 and and 33 provide provide thethe marked markedup upTSTSpages pagesfor forBraidwood Braidwoodand andByron ByronStations, Stations, respectively, for the proposed respectively, for the proposed changes. changes.

Attachments Attachments 4 and 55 include include the marked up TS Bases Bases pages pagesassociated associatedwith withthe theproposed proposed changes changesand andareareprovided providedfor forinformation informationonly.only.

Page Page 33 of of12 12

ATTACHMENT 1 I Evaluation of Evaluation of Proposed Proposed Changes

3.0 TECHNICAL EVALUATION

EVALUATION

Background

On July 13, 2006, at 13, 2006, at aaNRC NRCinspection inspectionexit exitmeeting, meeting,the theNRC NRCidentified identifiedaapotential potentialGreen Greenfinding finding and associated non-cited violation violation forforWolf Wolf Creek Creek for for aa violation violationof ofTSTS 3.7.2 3.7.2 inin that a MSIV MSIV was was not restored restored to to OPERABLE OPERABLE status status within within the the 88 hour0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months hour Completion Completion Time Timeas asrequired required by TS 3.7.2, Required Action A.1. Shortly Action A.1. Shortly after the exit meeting, licensee requested a meeting meeting with the NRC NRC staff to to present information information regarding regarding the the Wolf Wolf Creek analyses and and compliance compliance with with Technical Technical Specifications. The Specifications. Thelicensee licenseewas wasnotified notifiedsubsequent subsequentto tothetheexit exitmeeting meetingand andprior priortotoaameeting meeting with the NRC with NRC staff staff that that the the potential potential Green Green finding finding and and associated associated non-cited non-cited violation violation waswas being being withdrawn pending further further review.

On August 16, 2006, Wolf Creek and Callaway Plant personnel met with the NRC staff staff (NRR (NRR and Region IV personnel) to provide information on the MSIV operation, design bases, safety safety analyses, and Technical Specifications. The Themeeting meetingwas wasan aninformational informationalmeeting meetingand andthethe NRC did not provide a specific specific position position at at the the meeting meeting (Reference (Reference2). 2).

On August 21, 2006, the NRC Project Manager communicated to Wolf Wolf Creek Creek personnel personnel that the position that SR 3.7.2.2 is is interpreted interpreted by by the the NRC NRC staff staffthatthatthetheSRSRrequires requiresboth bothactuator actuatortrains trains be surveillance tested. Since SinceSR SR3.0.1 3.0.1 requires requiresSRs SRsto tobe bemetmetandandthat thatfailure failuretotomeet meetaaSR, SR, whether such failure is experienced during the performance of of the SR SR oror between between performances performances of the SR, shall be a failure to meet the LCO. Therefore, Therefore,the thefailure failureofofananactuator actuatortrain trainisisaa failure to meet the SR which results in LCO 3.7.2 not not being being met met and and the MSIV MSIV should be be declared inoperable absent absent any any specific specific Conditions Conditionsassociated associatedtotoactuator actuatortrains.

trains.

On October 19, 2006, the NRC concluded in a memorandum (Reference 1) 1) that the loss of of an MSIV actuator actuator train would result result inin Callaway Callaway having having to to declare declarethe theassociated associatedMSIV MSIVinoperable.

inoperable.

The NRC staff interpretation results in interpretation results in declaring declaring an MSIV MSIVinoperable inoperablefor forthose thoseplants plantswith with dual dual MSIV actuator trains MSIV actuator trains when one actuatoractuator train is inoperable.

inoperable. The Theexisting existing Completion Completion Time for an inoperable MSIV MSIV doesdoes not typically provideprovide a reasonable amount amount of of time time toto effect effect repairs repairs to one inoperable actuator train. train. Declaring Declaring an an MSIV MSIVinoperable inoperableand andhaving havingto toenter enterthe the Condition(s) and Required Required Action(s) for an MSIV MSIV inoperable inoperable due due only only to to one one inoperable inoperable actuator actuator is train is unnecessarily restrictive. Therefore, EGC proposes to incorporate requirements restrictive. Therefore, EGC proposes to incorporate requirements specifically for the MSIV actuator trains within within TS 3.7.3.7.2 2 such that the specification specification would include Conditions Conditions and Required Actions to address inoperable MSIV MSIVactuator actuatortrains.

trains.

Technical Analysis Analvsis Main Steam Main Steam Isolation Valves (MSIVs) (MSIVs)

The MSIVs MSIVs isolate steam flow from the flow from the secondary secondary side of of the steam steam generators generatorsfollowing following aa steam line steam line isolation signal.

signal. One OneMSIVMSIV is installed in in each of the main steam lines outside outside the the containment and downstream downstream of of the main main steam steam safety safety valves.

valves. The TheMSIVs MSIVsprevent preventuncontrolled uncontrolled blowdown from blowdown frommore morethan than oneone steam steam generator generator in in the event of a postulated postulated design design basis basis accident. Each EachMSIVMSIV is is aa gate gatevalve valve with with aa double double gategatedesign designthatthatisishydraulically hydraulically operated.

As described described in in the the Updated Updated Final Final Safety SafetyAnalysis Analysis Report Report (UFSAR),

(UFSAR), the valve is designeddesigned to to Page 4 of of 12

ATTACHMENT 1I ATTACHMENT Evaluation of Evaluation of Proposed Proposed ChangesChanges close in close in less less than than 55 seconds seconds based on on the limiting accident of a steam line break outside the containment to containment to limit limit cool cool down down rate of the reactor coolant system.

Each MSIV Each MSIV is is equipped equipped with with two two redundant hydraulic actuator trains such that either actuator actuator train can train can independently perform the safety function to fast-close the valve on on demand.

demand. The The MSIVs fail MSIVs fail as as is is on on loss loss of of control control or actuation actuation power and and are interlocked with the Engineered Safety Features Safety Features (ESF) (ESF) system system to to auto close on the followingfollowing main steam line isolation isolation signals:

manual; low manual; low steam steam line line pressure; pressure; high negative rate rate steam line pressure; containment pressure high-high (Hi-2).

high-high MSIV Actuator MSIV Actuator Train Train The Braidwood and Byron Stations' MSIV configuration consists of of four four valves valves per per unit unit with with oneone valve per valve per loop.

loop. The MSIVs are hydraulically actuated actuated double double diskdisk gate gatevalves.

valves. The actuator system is designed to provide a rapid closure in the event of system of a receipt receipt of of an an isolation isolation signal.

signal.

The electrical design of the MSIV control circuit has independent independent and and redundant redundant "Active" "Active" train train (Train A)

(Train A) andand "Standby" "Standby" train train (Train (Train B) B) actuator actuator components.

components. Both the active and standby trains activated by the are activated the main main steam steam lineline isolation isolation signals.

signals. EachEach train is powered from a separate ESF division ESF division that is actuated by a separate and independent MSIV emergency emergency closure closure signal.

signal.

the 'A' For the 'A' and and '0D' MSIVs, the active trains are powered by the Division 11 ESF ESF bus,bus, while while thethe standby trains are powered powered by the the Division Division 22 ESF ESF bus.

bus. Conversely, Conversely, the 'B' 'B' and and 'C' 'C' MSIVs MSIVs active active trains are powered by the Division 2 ESF bus, while the standby standby trains trains are are powered powered by by the the Division 1 ESF Division ESF bus.

bus. Both Both MSIV MSIV actuator actuator trains trains (active (active and standby) will receive automatic closure signals on low steam line pressure signals signals in in any anyoneone steam steam line, line, high high negative negative steam steam pressure rate signals in any steam line, or on a high-high containment containment pressure pressure signal.

signal. Upon Upon receipt of a closure signal, one MSIV control solenoid valve per per individual individual train train energizes, energizes, allowing pilot air to shuttle a four-way valve per per individual individual train train in in the the necessary necessary positionposition to to allow allow pressurized hydraulic fluid to flow from the charged accumulators to the hydraulic hydraulic cylinder, cylinder, causing the double disk gate valve valve to close close and and isolate isolate the the associated associated steam steam lineline within within the the55 seconds closure criterion.criterion.

Because of complete redundancy (i.e., (Le., independent independent active active train train and and standby standby traintrain components),

components),

the actuator actuator is is capable of of performing its fast closure function with either one ofthe performing its fast closure function with either one of the two two hydraulic hydraulic systems. Assuming Assuming aa single single failure failure of ofone one of of the the redundant redundant actuator actuator trains, trains, thethe valve valve will will close close within five five seconds.

seconds. When both both thethe active active and and standby standby trains trains actuator actuatorcomponents componentsare areutilized, utilized, as is the case upon upon receipt receipt of of aa low low steam steam line line pressure, pressure, high-high high-high containment containmentpressure, pressure, manual, or high negative rate steam line pressure pressure signal, signal, thethe valve valve will will close close in in less less than than 55 seconds.

seconds.

A A pneumatic and and hydraulic hydraulic actuator actuator train is composed composed solely solely of of skid-mounted skid-mounted components componentsatatthe the MSIV location. The actuator MSIV location. actuator train train does does notnotinclude include anyanyportion portion of of the the analog analog channels channelsoror protection protection system system actuation actuation logic logic andand actuation actuation relays relaysthatthatprovide provideinputs inputsto tothe thevalve valveactuator actuator trains.

trains. TheThe Engineered EngineeredSafety SafetyFeatures FeaturesActuation ActuationSystem System(ESFAS)

(ESFAS)Instrumentation Instrumentation specification specification provides separate separateConditions, Conditions,Required RequiredActions, Actions, andandSurveillance SurveillanceRequirements Requirements for for the analog channels channels andandprotection protection system systemlogic logicand andrelays.

relays.

Page Page 55 of of1212

ATTACHMENT 11 Evaluation of Proposed Changes Justification for the Completion Times is as follows:

Condition A - With only a single actuator train inoperable on one MSIV, a Completion Time Time of 7 days for Required Action A.1 A.1 is reasonable due due toto the the fact fact that that withwith one one actuator actuatortrain train inoperable andand the dual-redundant actuator actuator design, the affected affected valve valve would would stillstill be be capable capable of closing on demand (assuming no additional failures) via via the the remaining remaining OPERABLEOPERABLE train. The actuator train. The proposed proposed 77 dayday Completion Completion Time Time takes takes into into account account the the design design redundancy, reasonable time for repairs, and the low redundancy, low probability probability of of aa design design basis basis accident accident occurring during this period.

period.

Condition B - With one inoperable actuator Condition actuator train on on one one MSIVMSIV and and one one inoperable inoperable actuatoractuator train on another MSIV, such that that the the actuator actuator trains trains are are not not in in the the samesame ESF ESF division, division, aa Completion Time of 72 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months hours for Required Required Action Action B.1 B.1 is is reasonable.

reasonable. This This is is based based on on the dual-redundant actuator train design which ensures ensures that that withwith only only one one actuator actuatortrain train inoperable on each of the affected MSIVs, each each MSIVMSIV would would still still be be capable capable of of closing closing on on demand, assuming no additional demand, additional failures.

failures. Compared Compared to to Condition Condition A A however, however, itit is is appropriate to have a shorter Completion Time for for Condition Condition BB since since withwith anan actuator actuatortrain train inoperable on each of two MSIVs, there is is an an increased increased likelihood likelihood that that an an additional additional failurefailure (such as the failure of an actuation logic train) would cause cause an an MSIV MSIV to to fail fail to to close.

close.

Condition C - With one inoperable actuator actuator train train on on one one MSIVMSIV and and one one inoperable inoperable actuatoractuator train on another MSIV, but but with both both inoperable inoperable actuatoractuator trainstrains in in the the same same ESF ESF division, division, aa Completion Time of 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months for Required Required Action Action C.1 C.1 is is appropriate.

appropriate. Like Like thethe above above cases, cases, the dual-redundant dual-redundant actuator actuator train design design for for each each MSIV MSIV ensures ensures that that aa single single inoperable inoperable train for any valve actuator train valve would would not prevent the the affected affected valvevalve from from closing closing on on demand.

demand. In In this regard, 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months hour Completion Time Time is is reasonable reasonable and and conservative conservative since since onlyonly one one actuator train per valve is permitted to be be inoperable inoperable (for (for twotwo MSIVs),

MSIVs), so so that that the the remaining remaining OPERABLE actuator actuator train on each affected affected MSIVMSIV remains remains capablecapable of ofeffecting effecting valve valve closure closure on demand (assuming failures). AA Completion (assuming no additional failures). Completion Time Time of of 24 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months hours is is also also considered appropriate given the low low probability probability of of an an event event occurring occurring during during suchsuch an an would demand interval that would demand MSIV MSIV closure.

closure. Additionally, Additionally, the CompletionCompletion Time is consistent with Condition G of of TS TS 3.3.2, 3.3.2, "Engineered "Engineered Safety Safety Feature Feature Actuation Actuation System System (ESFAS)

(ESFAS)

Instrumentation," which provides a 24-hour 24-hour Completion Time for for restoring restoring one one train train to to OPERABLE status. Condition Condition G G isis applicable applicable to to Function Function 4.b 4.b (Steam (Steam Line Line Isolation Isolation- -

Automatic Actuation LogicLogic and and Actuation Actuation Relays)

Relays) which which provides provides the the actuation actuation logic logicfromfrom the the Solid State Protection System to the actuator trains. trains. AA loss loss of of one one actuation actuation logiclogic train would be equivalent equivalent to aa loss loss of of all all actuator actuator trains trains thatthat receive receive aa signal signal from from that that actuation actuation logic.

However, compared to the Required Action for for Condition Condition B B above, above, aa shorter shorter Completion Completion Time for Condition C is is appropriate appropriate since since with with two two actuator actuator trainstrains inoperable inoperable in in the the same same ESF division, an additional failure such as the failure of of anan actuation actuation logic logic train train in in the the other other ESF division could cause both affectedaffected MSIVsMSIVs to to fail fail to to close close on on demand.

demand.

For Conditions D and E, the Completion Time Time of of "immediately" "immediately" is is conservative conservative and and appropriate. ForForCondition ConditionD, D,for forexample, example,when whenboth bothactuator actuatortrains trainsforforoneoneMSIVMSIVare are inoperable, it is appropriate to require immediately immediately declaring the the valve valve inoperable inoperable since since having both actuator actuator trains inoperable inoperable would constituteconstitute aa condition condition that that renders renders the the affected affected Page 6 of of 1212

ATTACHMENT I ATIACHMENT1 Evaluation of Proposed Proposed Changes MSIV incapable of closing on demand.

With respect to Condition E, for the Condition when the Required Required ActionAction and and associated associated Completion Time Completion Time of of Condition Condition A, A, B, B, oror CC is is not not met, met, itit follows follows thatthat the the affected affected MSIV(s) MSIVs) should immediately be declared inoperable since the assumption should assumption is is that that the the Completion Completion Time(s) of Condition Time(s) Condition A, A, B, B, oror CC has has expired expired or or cannot cannot be be met.

met. This "default" Condition Condition is in keeping with keeping with the the intent that when when only the actuator trains for affected MSIVs MSIVs are are inoperable inoperable (and not the (and the valves valves themselves),

themselves), the Conditions and Required Actions for for thethe inoperable inoperable valve actuator trains should be entered first, and then ifif those Required Required Actions Actions cannot cannot be be met, the met, the affected MSIVs MSIVs should should be declared inoperable so that the Conditions and and Required Required inoperable valves Actions for the inoperable valves areare then then entered.

entered. Required Required Action Action E.1 E.1 ensures ensures the the affected MSIV(s) affected MSIVs) are are promptly promptly declared inoperable.

inoperable. This This format format or or approach approach is consistent with other Technical Specifications and the format of of the Improved Improved Standard Standard TechnicalTechnical Specifications (NUREG-1431).

portion of Condition E, i.e., for the condition when three or For the other portion or more more actuator actuator trains trains are inoperable, inoperable, it is conservative and appropriate as well to immediately immediately declare declare the the affected affected MSIVs inoperable MSIVs inoperable for for this this condition.

condition. For For the situation situation of of having three inoperable actuator trains, for example, such a condition could involve involve two inoperable inoperable actuator actuator trainstrains on on one one valve and one inoperable actuator train on another valve, or or one one inoperable inoperable actuator actuator traintrain on on each of three each three valves.

valves. In In each each case, case, thethe inoperable inoperable actuator actuator trains trains could could all be in in the same division or ESF division or be be staggered staggered among among the the two two ESF ESF divisions.

divisions. In In the former case, a single assumed failure such as an instrument instrument logiclogic train failure could cause cause one one or or two two valves valves to to fail to close onon demand.

demand. In In the the latter latter case, case, suchsuch aa single single failure could could cause cause either either none none of of the valves to failfail to close on demand, demand, or all all three three to to fail fail toto close close on on demand.

demand. Thus, Thus, declaring the immediately declaring the affected affected MSIVs MSIVs inoperable inoperable is is appropriate.

appropriate. In any any case, the conditions addressed by Condition E would constitute an an inoperability inoperability that that exceeds exceeds the the scope of any of the conditions addressed by by Conditions A, B. B. or or C, C, and and itit isis conservative conservative in in this case to simply require declaring all of of the affected MSIVs MSIVs inoperable.

inoperable.

The Bases of Surveillance Requirements (SR) 3.7.2.2 are are revised revised to to clearly clearly identify identify that that the the MSIV actuator trains trains are are required required to to bebe tested tested in in accordance accordance with with the the SR.

SR. Since Since the current SR do not clearly articulate applicability to the actuator actuator trains and and the the NRC NRC staff staff interpretation is that the actuator trains are encompassed within the SR, aa revision revision to to the the SR SR Bases to clarify this pointpoint is is appropriate.

appropriate.

A probabilistic risk analysis (PRA) was performed to evaluate evaluate the the risk risk impacts impacts of ofthe the proposed proposed Completion TimesTimes associated associated with with the the MSIV MSIV actuator trains. trains. This risk risk analysis analysis was not not used used to establish the proposed Completion Times; however, however, itit waswas usedused to to validate validate the the acceptability acceptabilityof of the proposed Completion Times. Times. The The risk risk analysis analysis followed followed the the guidance guidance suggested suggested in in Regulatory Guide (RG) (RG)1.174 1.174 and and RGRG 1.177 1.177 to to determine determine the the significance significance of of the the proposed proposed Completion Completion Times.

Times.

The risk risk analysis examined two sets sets of of risk risk metrics, metrics, which which are are the the change change in in annual annual average average core damage frequency frequency (CDF)/Iarge (CDF)lIarge early early release frequency (LERF), and and the the incremental incremental conditional core damage probability (ICCDP)/incremental (ICCDP)/incremental conditional conditional largelarge early early release probability (ICLERP). The The risk risk analysis analysis modeled modeled the the allowed allowed outageoutage times times (AOTs)

(AOTs) proposed proposed as Completion Times for TS TS Conditions A, A, B,B, and and C. C. The The calculation calculation used used in in the the analysis analysis Page 7 of of 12 12

ATTACHMENT 1I ATTACHMENT Evaluationof Evaluation of Proposed Proposed Changes represented the proposedthe represented Completion Times for proposed Completion eachforcondition's Times each condition's configuration configuration overoverthe thefuel fuel cycle for each Braidwood and Byron Stations' unit. unit.

Based on the analysis, analysis, the the risk risk metrics metrics results results for for each each Braidwood Braidwood and and Byron Byron Stations' Stations' unit unit are are well below well below the the recommended recommended values values of of RG RG 1.174 1.174and andRG RG1.177 1.177as asshown shownininthe thefollowing following table, table, which demonstrates which demonstrates that that the the risk risk of the proposed proposed Completion Completion Times are are acceptable.

acceptable.

Proposed Completion Times Risk Results Results Risk Metric Target Braidwood Unit Braidwood Unit 1I Braidwood Unit 2 Byron Unit Byron Unit 1I ByronByron Unit 2 OCDF boCDF 1.0E-6 9.17E-10 9.17E-10 9.17E-10 9.39E-10 ALERF boLERF 1.0E-7 7.82E-11 7.S2E-11 9.79E-1 1 9.79E-11 7.49E-11 1.06E-10 ICCDP 5.0E-7 1.01E-10 E-10 1.01 E-10 1.01 E-10 1.01E-10 1.04E-10 ICLERP 5.0E-8 5.0E-S 1.01 E-11 1.01E-11 1.26E-11 9.59E-12 1.21 E-11

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria The following NRC requirements and and guidance guidance documents documents are areapplicable applicableto tothethereview reviewof ofthe the proposed changes.

10 CFR 50 50, ,Appendix AppendixA, A, General GeneralDesign DesignCriterion Criterion (GDC) 2, 2, "Design basesbases forfor protection protection against natural phenomena," requires requires that the safetysafety related related portion portion of of the the Main Main Steam SteamSupply Supply System be protected protected from from the effects effects of of natural natural phenomena, phenomena, such such asasearthquakes, earthquakes,tornadoes, tornadoes, hurricanes, floods, and external external missiles.

missiles.

10 1 CFR 50 0 CFR 50,, Appendix Appendix A,A, GDC GDC 4, 4, "Environmental "Environmental and and dynamic dynamic effects effects design design bases," requires that the Main Steam Supply Supply System System be be designed designed to to remain remain functional functional after after a safe shutdown earthquake or to perform its intended function following following postulated postulated hazards hazards such such as as internal internal missiles, or or pipe break.

break.

10 CFR 50,50, Appendix AppendixA, A, GDC GDC22, 22,"Protection "Protectionsystemsystemindependence,"

independence,"requires requiresthat thatthe theMain Main Steam Supply System be be designed to to assure assure that that the the effects effects ofofnatural natural phenomena, phenomena, and and of of normal operating, maintenance, testing, and and postulated postulated accident accident conditions conditions on on redundant redundant channels do not result in loss of of the protection protection function, function, or or be be demonstrated demonstrated to to be be acceptable acceptable on on some other other defined defined basis.

basis.

10 CFR 50,50, Appendix Appendix A,A, GDC 34, "Residual "Residual heatheatremoval,"

removal," requires requires that that component component redundancy redundancy be be provided provided forfor the Main Main Steam Supply System so so that that safety safety functions functions can can be be performed, assuming assumingaasinglesingleactive activecomponent componentfailurefailurecoincident coincidentwith withthetheloss lossofofoffsite offsitepower.

power.

10 CFR 50,50,Appendix Appendix A,A, GDC GDC 57, "Closed "Closed system system isolation isolation valves,"

valves," requires requires that thatthe theMain Main Steam Steam Supply Supply System System line line that that penetrates penetratesprimary primaryreactor reactorcontainment containmentand andisisnot notpart partofofthe the reactor coolant pressure pressure boundary boundaryor orisis not not connected connecteddirectlydirectly to to the the containment containment atmosphere atmosphere shall have at at least leastone onecontainment containmentisolation isolation valve.

valve. ThisThisvalve valveshall shallbebeeither eitherautomatic, automatic,or or Page 8S of of 1212

ATTACHMENT 1I ATIACHMENT Evaluation of Proposed Evaluation Proposed Changes locked closed, locked closed, or capable of remote manual operation, be located outside containment containment and and as as close to the close the containment as practical.

10 CFR 10 CFR 50.36(c)(2),

50.36(c)(2), "Limiting "Limiting conditions for operation," paragraph (i) defines the limiting conditions for operation as the lowest functional capability or performance levels of conditions of equipment equipment required for safe operation of of the the facility.

facility. When a limiting condition for operation of of a nuclear nuclear reactor is not met, met, the licensee shall shut down the reactor or follow any any remedial remedial action action permitted by the permitted the technical technical specifications specifications until until the the condition condition can can be be met.

met. Furthermore, Criterion 3 of 10 CFR 50.36(c)(2)(ii) requires that a TS LCO must be established for for a structure, structure, system, system, oror component that is part of the primary success path and functions to to mitigate mitigate aa design design basis basis accident or transient that either assumes the failure of or presents presents aa challenge challenge to to the the integrity integrity of of a fission product barrier.

50.36(c)(3), "Surveillance requirements," defines surveillance requirements as 10 CFR 50.36(c)(3), as requirements relating to test, calibration, or inspection to assure that the the necessary necessary quality quality of of systems and components is maintained, that facility operation operation will will be be within within safety safety limits, limits, and and that the limiting conditions for operation will be met. met.

The proposed changes do do not not affect affect the MSIVs MSIVs and and associated associated actuator actuatortrain train design designand and operation, which operation, which continue continue toto meet allall the the GDC GDC requirements.

requirements. The The proposed proposed TS TS changes changes are are consistent with and in compliance with the above regulatory regulatory requirements requirements and and criteria.

criteria.

Therefore, the proposed proposed changes changes will assure safe safe operation operation byby continuing continuing to to meet meetapplicable applicable regulations and requirements.

requirements.

4.2 Precedents The NRC has approved similar license amendment amendment requests requests toto revise revise TS TSforformain mainsteam steam isolation valves actuator actuator trains trains as as follows:

follows:

1. Letter from Jack Donohew (NRC) to Charles Naslund (Union (Union Electric Electric Company),

Company), "Callaway "Callaway Plant, Unit 1 - Issuance of Amendment Re: Re: Main Steam Isolation Valve Actuator Main Steam Isolation Valve Actuator Trains Trains (TAC No. MC7212)," dated June 16, 16, 2006 2006 (ADAMS (ADAMS Accession Accession Number Number ML0608101690).

ML0608101690).

2. Letter from Jack Donohew (NRC) to Rick Muench (Wolf (Wolf Creek Creek Nuclear Nuclear Operating Operating Company), 'Wolf

'Wolf Creek Creek Generating Generating Station Station -- Issuance Issuance of ofAmendment AmendmentRe: Re:Addition Additionofof Actuator Trains to Main Steam and and Main Main Feedwater Feedwater Isolation Isolation Valves Valves Technical Technical Specifications (TAC No. MD2895)," dated dated November November 7, 2006 (ADAMS 7,2006 (ADAMS Accession Accession Number Number ML062610085).

ML062610085).

3. Letter from from Jack Jack Donohew (NRC) to James James Levine Levine (Arizona (Arizona Public Service Service Company),

Company), "Palo "Palo Verde Nuclear Nuclear Generating Generating Station, Station, Units Units 1, 1, 2, 2, and and 33-- Issuance IssuanceofofAmendments AmendmentsRe: Re:Main Main Steam Steam Isolation IsolationValve Valve Actuator Actuator Trains Trains (TAC (TAC Nos.

Nos. MD3066, MD3066, MD3067, MD3067, and and MD3068),"

MD3068)," dateddated November November 17, 17, 2006 2006(ADAMS Accession Number (ADAMS Accession NumberML063110505).

ML063110505).

Page 99 of of 12 12

ATTACHMENT 1 I Evaluation of of Proposed Proposed Changes Changes 4.3 No Significant Hazards Consideration In accordance with In with 10 CFR 50.90, Exelon Generation Company, LLC, (EGC), (EGC), is is requesting requesting amendments to Facility Operating License Nos. Nos. NPF-72 NPF-72 and and NPF-77 NPF-77 for for Braidwood Braidwood Station, Station, Units 1 and 2, and Facility Operating License License Nos.Nos. NPF-37 NPF-37 and and NPF-66 NPF-66 for for Byron Byron Station, Station, Units Units 1 and 2.

1 The proposed The proposed changes changes will will revise revise Technical Technical Specification Specification (TS) 3.7. 2, "Main Steam 3.7.2, Steam Isolation Isolation Valves (MSIVs)," to incorporate the MSIV MSIVactuator actuatortrains trainsintointothe theLimiting Limiting Condition Condition for for Operation (LCO) and provides associated Conditions Conditions and and Required Required Actions.

Actions. Additionally, Surveillance Requirement (SR) 3.7. 2.2 is 3.7.2.2 is revised to clearly identify that the MSIV MSIVactuator actuatortrains trains are required required to be tested tested inin accordance accordance withwith the the SR. The proposed SR. The proposed changes changes will will address NRC NRC staff interpretation that SR 3.7. 2.2 requires both actuator trains for a single 3.7.2.2 single valve to to be be tested.

tested.

The NRC staff interpretation interpretation results results in indeclaring declaring an an MSIV MSIV inoperable when one one actuator actuator train train is is inoperable.

inoperable. The Theexisting existing Completion Completion Time of of 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months hours for an inoperable inoperable MSIV due to one inoperable actuator actuator train train is is not commensurate commensurate with with the the safety safetysignificance significance of ofthe thecondition.

condition.

Therefore, new new Conditions, Conditions, Required Actions, and Completion Times for for inoperable actuator actuator train(s) are being being proposed.

proposed.

EGC has evaluated whether or not a significant hazards consideration is involved with the proposed amendment amendment by by focusing focusing onon the the three three standards standardsset setforth forthinin1010CFR CFR50.92(c),

50.92(c),

"Issuance of of amendment,"

amendment," as as discussed discussed below:

below:

1. Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response

Response: No. No.

The proposed changes provide requirements for for MSIVs that have have dual actuators which receive signals from separate instrumentation trains. The Thedesign designand andfunctional functional performance requirements, operational operational characteristics, characteristics, and and reliability reliabilityofofthe theMSIVs MSIVsand and actuator trains are unchanged. There Thereisisno noimpact impacton onthethedesign designsafety safetyfunction functionof ofthe the MSIVs to close close (as an accident mitigator), nor nor is is there there any any change change with with respect respect to to inadvertent closure of an MSIV (as a potential transient initiator). Since Since no nofailure failure mode mode or or initiating condition condition that could could cause an accident (including any plant transient) is created or affected, the change cannot involve a significant increase increase in the probability probability of an accident previously evaluated.

With regard With regard to to the the consequences consequences of ofananaccident accidentandandthe theequipment equipmentrequired requiredfor formitigation mitigation of of the accident, the the proposed proposed changes changesinvolve involveno nodesign designororphysical physicalchanges changestotothe theMSIVs MSIVsor or any other other equipment equipmentrequired requiredforfor accident accidentmitigation.

mitigation. WithWith respect respect toto MSIV MSIV actuator actuator train Completion Times, Completion Times,the the consequences consequences of of an accident accident areare independent independent of of equipment equipment Completion Times Completion Times as as long long as adequate adequateequipment equipmentavailability availability is maintained. The Theproposed proposed MSIVactuator MSIV actuator Completion CompletionTimes Timestake take into into account account thethe redundancy of the actuator actuator trains and are are limited limited in extent consistent consistentwithwith other otherCompletion Completion Times Times specified specified in in the theTechnical Technical Specifications. Adequate equipmentequipmentavailability availability would therefore continue to be be required required by by the Technical Specifications.

Specifications. On this basis, the consequences consequencesof ofapplicable, applicable, analyzed analyzed accidents are are not not significantly affected by significantly affected by the the proposed proposed changes.

changes.

Page 10 of 12

ATTACHMENT 1I ATTACHMENT Evaluation of Proposed Evaluation Proposed Changes Therefore, the Therefore, the proposed proposed changes do not involve aa significant significant increase in in the the probability or consequences of an accident previously evaluated.

consequences evaluated.

2. Does

2. Does the the proposed proposed amendment create the possibility of a new or different kind of of accident accident from any accident previously evaluated?

from Response: No.

Response

The proposed The proposed changes to incorporate requirements for the MSIV actuator actuator trains do do not not involve any involve any design design or physical physical changes to the facility, including the MSIVs MSIVs and and actuator actuator themselves. No trains themselves. No physical physical alteration alteration of of the the plant is is involved, as no no new or different type equipment is of equipment is to to be be installed.

installed. The The proposed proposed changes do not not alter alter any assumptions made made in the in the safety safety analyses, analyses, nor do they involve any changes to plant procedures for ensuring ensuring that that operated within the plant is operated within analyzed analyzed limits.

limits. As such, such, nono new new failure modes or mechanisms could cause a new or different kind of accident from any that could any previously previously evaluated evaluated are are being being introduced.

Therefore, the proposed changes do not create the possibility of of aa new new oror different different kind kind of of accident from any accident accident previously previously evaluated.

evaluated.

3. Does the proposed amendment involve a significant reduction in

3. in margin margin of of safety?

safety?

Response: No.

The proposed changes to incorporateincorporate requirements requirements for for the the MSIV MSIV actuator actuator trains trains do do not not alter alter the manner in whichwhich safety limits or limiting limiting safety safety system system settings settings are are determined.

determined. No No changes to instrument/system instrument/system actuation actuation setpoints setpoints are are involved.

involved. The The safety safety analysis analysis acceptance criteria are not affected by this change and and the the proposed proposed changes changes willwill not notpermit permit plant operation in a configuration outside the design in configuration outside the design basis. basis.

Therefore, the proposed changes do do not not involve involve aa significant significant reduction reduction in in aa margin margin of ofsafety.

safety.

Based on the above, EGC concludes that that the the proposed proposed amendments amendments do do not not involve involve aa significant significant hazards consideration under the standards set forth in 10 10 CFR CFR 50.92(c),

50.92(c), and, and, accordingly, accordingly, aa finding ofof no no significant hazards hazards consideration consideration is is justified.

4.4 Conclusions In conclusion, based In conclusion, based on on the the considerations considerations discussed discussed above, (1) there there is reasonable assurance assurance that that the the health health and and safety safetyofof the the public public will not be will not be endangered endangered by by operation in the proposed proposed

manner, manner, (2) (2) such suchactivities activities will will be conducted conducted in in compliance compliance with with the the Commission's Commission'sregulations, regulations, and and (3)

(3) the issuance issuanceof ofthe the amendment amendmentwill will not be be inimical inimical to to the the common common defense and and security security or or to the the health health and andsafety safetyofofthe thepublic.

public.

Page 11 11 of of 12 12

ATTACHMENT I ATIACHMENT1 Evaluation of Proposed Changes 5.0 CONSIDERATION ENVIRONMENTAL CONSIDERATION EGC has evaluated EGC evaluated thethe proposed proposed amendments for environmental environmental considerations.

considerations. The The review review has resulted in the determination that the proposed proposed amendment amendment would would change change aa requirement requirement with respect to installation or use of of aa facility component component located located within within the the restricted restricted area, area, as as defined in 10 CFR 20, 20, or would would change an inspection or surveillance surveillance requirement.

requirement. However, However, the proposed amendments do not not involve involve (i)

(i) aa significant significant hazards hazards consideration, consideration, (ii)(ii) aa significant significant change in the types or significant increase in in the amounts amounts of of any any effluent effluent that that may may be be released released offsite, or (iii) a significant increase in individual or offsite, or cumulative occupational occupational radiation radiation exposure.

exposure.

Accordingly, the proposed amendments meet meet the the eligibility eligibility criterion criterion for for categorical categorical exclusion exclusion set set forth in 10 CFR 51.22(c)(9).

forth 51.22(c)(9). Therefore, Therefore, pursuant pursuant to to 10 10 CFR CFR 51.22(b),

51.22(b), no no environmental environmental impactimpact statement or environmental assessment assessment needneed be be prepared prepared in in connection connection withwith the the proposed proposed amendments.

6.0 REFERENCES

1. NRC Memorandum, "Operability Determination for

1. for the Callaway Plant Technical Specifications Requirements When One Main Steam Steam Isolation Isolation Valve Valve Actuator Actuator Train Train is is Removed from Service," dated October October 19, 2006 (ADAMS 19,2006 (ADAMS Accession Accession Number Number ML061730396)

2. Summary of August 16, 2006, Meeting 16,2006, Meeting with with Representatives Representativesof ofWolf Wolf Creek Creek Nuclear Nuclear Operating Corporation Corporation and and Union Union Electric Electric Company Company dated datedSeptember September20, 20,2006 2006(ADAMS (ADAMS Accession Number Number ML062410484)

ML062410484)

3. Technical Specification Task Force

3. Force (TSTF)

(TSTF) Improved Improved Standard Standard Technical Technical Specifications Specifications Change Traveler, TSTF-504-T, Revision Revision 0, 0, "Revised "Revised thethe MSIV MSIV and and MFIV MFIV Specifications Specifications to to Provide Actions for Actuator Trains," dated dated September September 14, 14, 2007 2007 Page 12 12 of of 12 12

ATTACHMENT 2 ATTACHMENT Proposed Technical Proposed Technical Specifications Specifications Changes Changesfor for Braidwood Braidwood Station, Station, Units Units 1I and 2 Braidwood Station, Braidwood Station, Units Units 1I and 2 Facility Operating Facility Operating License License Nos.

Nos. NPF-72 and NPF-77 Mark- up of Mark-up of Technical Technical Specifications Page 3.7.2-3.7.2-11 3.7.2 - 2 3.7.2-2

MSIVs MSIVs 3.7.2 3.7.2 3.7 3.7 PLANT SYSTEMS PLANT SYSTEMS 3.7.2 3.7.2 Main Steam Isolation Main Steam Isolation Valves Valves (MSIVs)

(MSIVs) and their associated actuator trains LCO LCO 3.7.2

3. 7.2 Four MSIVs shall be OPERABLE.

APPLICABILITY:

APPLICABILITY: MODE 1, MODE 1, MODES MODES 2 and 33 except 2 and except when when all all MSIVs MSIVs are are closed.

closed.

ACTIONS ACTIONS CONDITION CONDITION REQU I RED ACTION REQUIRED ACTI ON COMPLETION TIME COMPLETION TIME ST 1 A. One MSIV inoperable One MSIV inoperable in A.l1 in ,_A. Restore Restore MSIV to MSIV to hours 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months MODE MODE 1.1. F OPERABLE status.

OPERABLE status.

~.

19. Required Action and Required Action and 4.1 Be in MODE Be in MODE 2.

2. hours 66 hours7.638889e-4 days 0.0183 hours 1.09127e-4 weeks 2.5113e-5 months 4 associated Completion associated Completion Time Time of Condition A of Condition A F

not met.

t.

C. ---------NOTE---------

NOTE --------- I f.l .1 Close MSIV.

Close MSIV. hours 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months Separate Condition Separate Condition entry entry isis allowed allowed for for AND each MSIV.

each MSIV.

E.2 ^ Verify MSIV is Verify MSIV is Once per 77 days Once per days closed.

closed.

One or more MSIV inoperable in MODE 2 or 3. H~--------~----'

B.

1=}. Required Required Action and Action and 1 Be in MODE Be in MODE 3.

3. 66 hours7.638889e-4 days 0.0183 hours 1.09127e-4 weeks 2.5113e-5 months hours associated Completion associated Completion Time Time ofof Condition Condition -Gf AND not met. f H not met.

.9.2 Be in MODE Be in MODE 4.

4. 12 hours 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months BRAIDWOOD UNITS 11 &&22 BRAIDWOOD -- UNITS 3.7.2 3.7.2 -- 47 Amendment Amendment 009

INSERT 11 CONDITION REQUIRED ACTION COMPLETION TIME A. One MSIV actuator train A.1 Restore MSIV actuator train 7 days inoperable. to OPERABLE status.

B. Two MSIVs each with B.1 Restore one MSIV actuator 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months 72 one actuator train train to OPERABLE status.

inoperable such that the inoperable actuator trains are in different ESF Divisions.

C. Two MSIVs each with C .1 C.1 Restore one MSIV actuator 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months one actuator train train to OPERABLE status.

inoperable and both inoperable actuator trains are in the same trains ESF Division.

D. Two MSIV actuator D.1 Declare the affected MSIV MSIV Immediately trains inoperable on the inoperable.

same MSIV.

E. Three or more MSIV E.1 Declare each affected Immediately actuator actuator trains MSIV inoperable.

inoperable.

OR Required Action and associated Completion Time of Condition A, B, B, or C not not met.

met.

MSIVs MSIVs 3.7.2 3.7.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE REQUIREMENTS SURVEILLANCE SURVEILLANCE FREQUENCY FREQUENCY SR 3.7.2.1 SR 3.7.2.1 -------------------NOTE--------------------

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

Only Only required required to be performed to be in MODES performed in MODES 11 and 2.

and 2.

Verify closure time of each MSIV is Verify closure time of each MSIV is In In accordance accordance

~

< 5 seconds.

5 seconds. with with thethe Inservice Inservice Testing Program Testing Program SR 3.7.2.2 SR 3.7.2.2 -------------------NOTE--------------------

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

Only required to Only required be performed to be performed in in MODES MODES 11 and 2.

and 2.

a ain actuates the Ve rify ea Verify ch MS IV -NA~~Tn:-rrjp"""=lSnlriflrirl1 eachMSIV e iso a ion IInn aaccordance cco rd ance position po sition on on an an actual actual or simulated with with thethe actuation signal.

actuation signal. Surveillance Surveillance Frequency Frequency Control Program Control Program BRAIDWOOD -- UNITS BRAIDWOOD &

UNITS 11 & 22 3.7.2--2:

3.7.2 - -2 Amendment Amendment 1651165

ATTACHMENT 33 ATTACHMENT ProposedTechnical Proposed TechnicalSpecifications SpecificationsChanges Changesfor forByron ByronStation, Station,Units Units1I and 2 Byron Station, Byron Station,Units Units1I and 2 Facility Operating Facility Operating license License Nos. NPF-37 and NPF-66 Mark-up of Technical Specifications Mark-up Specifications Page 3.7.2-3.7.2-11 3.7.2-2

MSIVs MSIVs 3.7.2 3.7.2 3.7 3.7 PLANT PLANT SYSTEMS SYSTEMS 3.7.2 3.7.2 Main Main Steam Isolation Valves Steam Isolation Valves (MSIVs)

(MSIVs) end their associated actuator trains LCO

[CO 3.7.2

3. 7.2 Four Four MS MSIVs shall be OPERABLE.

APPLICABI LITY:

APPLICABILITY: MODE 1, MODE 1, MODES MODES 22 and and 33 except except when when all MSIVs are all MSIVs are closed.

closed.

ACTIONS ACTIONS CONDITION CONDITION REQUIRED REQUIRED ACTION ACTION COMPLETION TIME COMPLETION TIME MISERY 1 A. One One MSIV inoperable in MSIV inoperable in X4.1 A.l Restore Restore MSIV MSIV toto 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months hours

^s it MODE MODE 1.1. OPERABLE status.

OPERABLE status.

[]

-R. Required Required Action and Action and -B..1 Be in MODE Be in MODE 2.

2. 66 hours7.638889e-4 days 0.0183 hours 1.09127e-4 weeks 2.5113e-5 months hours associated Completion associated Completion Time Time ofof Condition Condition A A not met.

not met.

-G.. ---------NOTE---------

NOTE --------- -G.

G.l 1 Close MSIV.

Close MSIV. 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months hours Separate Condition Separate Condition entry entry isis allowed allowed for for each MSIV.

each MSIV.

G.2 \ Verify MSIV Verify MSIV is is Once per 77 days Once per days closed.

closed.

One or more One or more MSIV MSIV inoperable inoperable in in MODE MODE 22 or 3.

or 3.

B.

-B. Required Action Required Action and and I B.l B.1 Be in Be in MODE MODE 3.

3. 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 6 hours associated Completion associated Completion Time of Time of Condition Condition 4-2-G / I AND not met.

not met.

B.2 Be in Be in MODE MODE 4.

4. 12 hours 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months BYRON -- UNITS BYRON &

UNITS 11 & 22 3.7.2 ---3:

3.7.2 -1 Amendment .f.(f6.

Amendment

INSERT 1 INSERT CONDITION CONDITION REQUIRED ACTION REQUIRED ACTION COMPLETION COMPLETION TIME TIME A. One A, One MSIV actuator actuator train train A,1 A.1 Restore Restore MSIV MSIV actuator train 77 days days inoperable.

inoperable. to OPERABLE status.

to status.

B. Two B. Two MSIVs each each with with B.1 B.1 Restore one Restore one MSIV MSIV actuator 72 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months one actuator train one OPERABLE status.

train to OPERABLE inoperable such that the inoperable actuator trains are in different trains ESF Divisions.

C. Two MSIVs each with C.1 Restore one MSIV actuator 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months one actuator actuator train train to OPERABLE status.

inoperable and both inoperable actuator trains are in trains in the same ESF Division.

D. Two MSIV MSIV actuator actuator D.1 0.1 Declare the affected affected MSIV Immediately Immediately trains inoperable on on the inoperable.

same MSIV.

E. Three oror more MSIV MSIV E.1 Declare each each affected affected Immediately Immediately actuator actuator trains trains MSIV MSIV inoperable.

inoperable.

OR OR Required Action Action and and associated associated Completion Completion Time Time ofof Condition Condition A, A, B, B,

or C not met.

MSIVs MSIVs 3.7.2 3.7.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE REQUIREMENTS SURVEILLANCE SURVEILLANCE FREQUENCY FREQUENCY SR SR 3.7.2.1 3.7.2.1 -------------------NOTE--------------------

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

Only required to Only required to be be performed performed in in MODES MODES 11 and and 2. 2.

Verify closure time Verify closure time ofof each each MSIV MSIV isis In In accordance accordance

<_ 55 seconds.

seconds. with the with the Inservice Inservice Testing Program Testing Program SR SR 3.7.2.2 3.7.2.2 -------------------NOTE--------------------

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

Only required to Only required to be be performed performed in in MODES MODES 11 and and 2. 2.

~- -----r~~t~~t;~ t~~i~-~~t~~t~~-

actuator train th~j r actuates the Verify each+MSIV each MSIV actuates

, 1 tee er to the i isolatlon to the so] ati on In In accordance accordance position on on an an actual actual oror simulated simulated with the with the actuation actuation signal.

signal. Surveillance Surveillance Frequency Frequency Control Program Control Program BYRON UNITS 11 &&22 BYRON -- UNITS 3.7.2 3.7. 2 --2:

Amendment 441417-1 Amendment 1711171

ATTACHMENT 4 ATTACHMENT Proposed Technical Proposed Technical Specifications Specifications Bases Bases Changes Changes for for Braidwood Braidwood Station, Station, Units Units 1I and and 22 Braidwood Station, Braidwood Station, Units 1 and 2 Facility Operating Facility Operating License Nos. NPF-72 and NPF-77 Mark-up of Mark-up of Technical Technical Specifications Bases Pages 83.7.2-1 B 3.7.2 - 1 83.7.2-3 B 3.7.2 - 3 83.7.2-4 B 3.7.2 - 4 83.7.2-5 B 3.7.2 - 5 83.7.2-6 B 3.7.2 - 6

B B 3.7 PLANT SYSTEMS 3.7 PLANT SYSTEMS B

B 3.7.2 Main Steam 3.7.2 Main Steam Isolation Isolation Valves Valves (MSIVs)

(MSIVs)

BASES BASES BACKGROUND BACKGROUND The MSIVs isolate The MSIVs isolate steam steam flow flow from from the the secondary secondary side side ofof the the steam generators following steam generators following aa High High Energy Energy Line Line Break Break (HELB).

(HELB).

MSIV closure terminates MSIV closure terminates flowflow from from the the unaffected unaffected (intact)

(intact) steam generators.

steam generators.

One One MSIV is located MSIV is located in in each each main main steam steam line line outside, outside, butbut close close toto containment.

containment. The MSIVs are The MSIVs are downstream downstream from from the the Main Steam Safety Main Steam Safety Valves Valves (MSSVs),

(MSSVs), toto prevent prevent MSSV MSSV isolation isolation from from the the steam steam generators generators by by MSIV MSIV closure. Closing the closure. Closing the MSIVs isolates each MSIVs isolates each steam steam generator generator from from the the others, others, andand isolates isolates the turbine, Steam the turbine, Steam Dump Dump System, System, and and other other auxiliary auxiliary steam supplies from steam supplies from the the steam steam generators.

generators.

i--~

The The MSIVs close on MSIVs close on aa main main steam steam isolation isolation signal signal generated generated by Steam by Steam Line Line Low Low Pressure, Pressure, Steam Steam Line Line High High Negative Negative Rate, Rate, or or High-2 containment pressure.

High-2 containment pressure. The The MSIVs MSIVs fail fail asas is is on on loss of control loss of control or or actuation actuation power.

power.

Each Each MSIV MSIV has has an an MSIV MSIV bypass bypass valve. Although these valve. Although these bypass bypass valves are valves are normally normally closed, closed, they they receive receive the the same same automatic automatic closure closure signal signal asas dodo their their associated associated MSIVs. The MSIVs MSIVs. The MSIVs maymay also also bebe actuated actuated manually.

manually.

A description of A description of the the MSIVs MSIVs isis found found in in the the UFSAR, UFSAR, Section 10.3 (Ref.

Section 10.3 (Ref. 1).1).

BRAIDWOOD UNITS 11 &&22 BRAIDWOOD -- UNITS B3.7.2--+/--

B 3.7.2 - -1 Revision Revision-9 .g.

BASES BASES APPLICABLE APPLICABLE The The design design basis basis ofof the the MSIVs MSIVs is is established established by by the the SAFETY SAFETY ANALYSES ANALYSES analysis analysis for for the the large large Steam Steam LineLine Break (SLB) outside Break (SLB) outside containment, containment, discussed discussed in in the the UFSAR, UFSAR, Section Section 15.1.5 15.1.5 (Ref.

(Ref. 2). It is 2). It is also also affected affected by by the the accident accident analysis analysis of of the SLB the SLB events events presented presented in in the the UFSAR, UFSAR, Section Section 6.2 6.2 (Ref.

(Ref. 3).

3).

The The design design precludes precludes the the blowdown blowdown of of more more than than one one steam steam generator, generator, assuming assuming a a single active component single active component failure failure (e.g.,

(e.g.,

the the failure failure ofof one one MSIV MSIV toto close close onon demand).

demand).

The The accident accident analysis analysis compares compares several different SLB several different SLB events events against against different acceptance criteria.

different acceptance criteria. The large SLB The large SLB outside outside containment containment upstream upstream of of the the MSIV is limiting MSIV is limiting for for offsite dose, offsite dose, although although a a break break inin this this short short section section of of main main steam steam header header has has aa very very low low probability.

probability. TheThe large large SLB SLB inside inside containment containment at at hot hot zero zero power power isis the limiting case the limiting case for for aa post post trip trip return return to to power.

power. TheThe analysis analysis includes includes scenarios with scenarios with offsite offsite power power available, available, andand with with a a loss loss ofof offsite offsite power power following following turbine turbine trip. With offsite trip. With offsite power power available, available, the reactor coolant the reactor coolant pumps pumps continue continue toto circulate circulate coolant coolant through through the the steam steam generators, generators, maximizing maximizing thethe Reactor Reactor Coolant System (RCS)

Coolant System (RCS) cooldown.

cool down. WithWith a a loss loss of of offsite offsite power, power, the response of the response of mitigating mitigating systems systems is is delayed.

delayed.

Significant Significant single single failures considered include failures considered include failure failure of of anan MSIV to close.

MSIV to close.

The MSIVs serve The MSIVs serve only only aa safety safety function function and and remain remain open open during power operation.

during power operation. These valves operate These valves operate under under the the following situations:

following situations:

a.

a. An HELB An HELB inside inside containment.

containment. In In order order to to maximize maximize thethe mass and mass and energy energy release release intointo containment, containment, thethe analysis analysis assumes that assumes that the the MSIV MSIV in in the the affected affected steam steam generator generator remains open.

remains open. For For this this accident accident scenario, scenario, steam steam isis discharged into discharged into containment containment fromfrom all all steam steam generators generators until the until the remaining remaining MSIVs MSIVs close. After MSIV close. After MSIV closure, closure, steam is steam is discharged discharged into into containment containment only only from from the the affected steam affected steam generator generator and and from from the the residual residual steam steam in the in the main steam header main steam header downstream downstream ofof the the closed closed MSIVs in MSIVs in the the unaffected unaffected loops. Closure of loops. Closure of the the MSIVs MSIVs isolates the isolates the break break from from thethe unaffected unaffected steam steam generators.

generators.

BRAIDWOOD -- UNITS BRAIDWOOD &

UNITS 11 & 22 BB 3.7.2 3.7.2 -- 22 Revision 00 Revision

BASES BASES APPLICABLE APPLICABLE SAFETY SAFETY ANALYSES (continued)

ANALYSES (continued) b.

b. A A break break outside outside of containment and of containment and upstream upstream from from thethe MSIVs MSIVs isis not not aa containment containment pressurization pressurization concern.

concern.

The The uncontrolled blowdown of uncontrolled blowdown of more than one more than one steam steam generator generator must must bebe prevented prevented to limit the to limit the potential potential for for uncontrolled RCS uncontrolled RCS cooldown cooldown and and positive reactivity positive reactivity addition.

addition. Closure Closure of of the the MSIVs isolates the MSIVs isolates break and the break and limits limits the the blowdown blowdown to to aa single single steam steam generator.

generator.

c.

c. A break downstream A break downstream of of the the MSIVs MSIVs will will bebe isolated isolated by by the the closure closure of of the the MSIVs.

MSIVs.

d.

d. Following Following a a steam steam generator generator tube rupture, closure tube rupture, closure of of the the MSIVs isolates the MSIVs isolates the ruptured ruptured steam steam generator generator from from the intact steam the intact steam generators generators to to minimize minimize radiological radiological releases.

releases.

e.

e. The The MSIVs are also MSIVs are also utilized utilized during during other other events events such such as as aa feedwater feedwater line line break. This event break. This event is is less less limiting limiting so so far far asas MSIV MSIV OPERABILITY OPERABILITY is is concerned.

concerned.

The MSIVs satisfy The MSIVs satisfy Criterion Criterion 33 ofof 10 10 CFR CFR 50.36(c)(2)(ii).

50.36(c)(2)(ii). andther associated actuator LCO

[CO This LCO requires This [CO requires thatthat four four MSIVs MSIVs in in the the steam steam lines lines bebe trains OPERABLE.

OPERABLE. The MSIVs are The MSIVs are considered considered OPERABLE OPERABLE when when the the isolation times are isolation times are within within limits, limits, and and they they close close on on an an ation actuation isolation actuation signal.

signal.

E2T B ^^

This LCO provides s LCO provides assurance assurance that that the the MSIVs MSIVs will will perform perform their design their design safety safety function function to to mitigate mitigate the the consequences consequences of of accidents that accidents that could could result result inin exposures exposures comparable comparable toto the the 10 10 CFR 50.67 (Ref.

CFR 50.67 (Ref. 4) 4) limits limits oror the the NRC NRC staff staff approved approved licensing basis.

licensing basis.

BRAIDW00D UNITS 11 &&22 BRAIDWOOD -- UNITS BB3.7.2 3.7.2 -- -33 Revision +/-

Revision 61

and required BASES actuator trains APPLICABI LITY APPLICABILITY The MSIVs must be The MSIVs'must be OPERABLE OPERABLE in in MODE MODE 1,1, andand in in MODES MODES 22 and and 33 except except when closed, when when closed, there is when there is significant significant massmass and and energy energy inin the the RCS RCS and and steam steam generators.

generators. When When the the MSIVs MSIVs are are closed, they are closed, they are already already performing performing the safety function.

the safety function. In In MODE MODE 4 4 the the steam steam generator generator energy energy is is low.

low.

In In MODE MODE 55 or or 6, 6, the the steam steam generators generators do not contain do not contain much much energy because their energy because their temperature temperature is is below below thethe boiling boiling point point of of water; water; therefore, therefore, the the MSIVs MSIVs are are not not required required for for isolation isolation ofof potential potential high high energy energy secondary secondary system system pipe pipe breaks in breaks in these these MODES.

MODES.

IN E T I ACTIONS ACTIONS A.

With one MSIV With one MSIV inoperable inoperable in in MODE MODE 1, 1, action action must must be be taken taken toto restore restore OPERABLE OPERABLE status status within within 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months .

hours. SomeSome repairs repairs toto the the MSIV can be MSIV can be made made with with the the unit unit hot.

hot. TheThe 88 hour0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months hour Completion Completion Time Time isis reasonable, reasonable, considering considering the the low low probability probability of of an an accident accident occurring occurring during this time during this time period period that that would would re aa closure require closure of of the the MSIVs.

MSIVs.

INSERT D The 8 hour Completion 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months Completion Time Time is is greater greater thanthan that that normally normally allowed allowed for containment isolation for containment isolation valves valves because because the the MSIVs MSIVs are valves that are valves isolate aa closed that isolate closed system system penetrating penetrating containment.

containment. These valves differ These valves differ from from other other containment containment isolation isolation valves valves in in that that thethe closed closed system system provides provides anan additional means for additional means for containment containment isolation.

isolation.

8.1 If the MSIV If the MSIV cannot cannot be be restored restored to to OPERABLE OPERABLE status status within within 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months , hours, the the unit unit must must bebe placed placed in in aa MODE MODE in in which which the the LCO LCO does does not not apply.

apply. To To achieve achieve this this status, status, the the unit unit must must be placed be placed in in MODE MODE 2 2 within within 6 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months hours andand Condition ould be Condition t ould be entered.

entered. The Completion Time The Completion Time is is reasonable, reasonable, based based onon operating operating experience, experience, to to reach reach MODE MODE 22 andand to to close close the the MSIVs MSIVs in in an an orderly manner and orderly manner and without without challenging challenging plant plant systems.

systems.

BRAIDWOOD UNITS 11 &&22 BRAIDWOOD -- UNITS B B 3.7.2-4 3.7.2 - 4 Revision Revision .g. 0

BASES BASES ACTIONS (continued)

ACTIONS (continued)

.27 Condition ~isis modified Condition modified byby aa Note Note indicating indicating that that separate separate Condition entry Condition entry is is allowed allowed for for each each MSIV.

MSIV.

Since the Since the MSIVs MSIVs are are required required to to be be OPERABLE OPERABLE in in MODES MODES 22 and 3, and 3, the the inoperable inoperable MSIVs MSIVs may may either either bebe restored restored toto OPERABLE status OPERABLE status or or closed.

closed. WhenWhen closed, closed, the the MSIVs MSIVs are are already in already in the the position position required required byby the the assumptions assumptions in in the the safety analysis.

safety analysis.

The 88 hour0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months The hour Completion Completion Time Time is is consistent consistent with with that that allowed allowed inn Condition i A~

Condition P4.

For inoperable For inoperable MSIVs MSIVs that that cannot cannot bebe restored restored toto OPERABLE OPERABLE status within status within the the specified specified Completion Completion Time, Time, but but are are closed, closed, the inoperable the inoperable MSIVs MSIVs must must be be verified verified onon aa periodic periodic basis basis toto be closed.

be closed. This This is is necessary necessary to to ensure ensure that that the the assumptions assumptions in the in the safety safety analysis remain valid.

analysis remain valid. TheThe 77day day Completion Completion Time is Time is reasonable, reasonable, based based onon engineering engineering judgment, judgment, in in view view of MSIV of MSIV status status indications indications available available in in the the control control room, room, and other and other administrative administrative controls, controls, toto ensure ensure that that these these

~lves are in valves are in the the closed closed position.

position.

~.g.~B.2 If If the the MSIVs cannot be MSIVs cannot be restored restored to to OPERABLE OPERABLE status status oror are are not closed within not closed the associated within the associated Completion Completion Time, Time, the the unit unit must must bebe placed placed inin aa MODE MODE inin which which the the LCO LCO does does not not apply.

apply.

To achieve this To achieve this status, status, thethe unit unit must must bebe placed placed atat least least inin MODE MODE 3 3 within within 6 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months , hours, andand in in MODE MODE 44 within within 1212 hours0.014 days 0.337 hours 0.002 weeks 4.61166e-4 months . The hours. The allowed Completion Times allowed Completion Times are are reasonable, reasonable, based based onon operating operating experience, experience, to to reach reach the the required required unit unit conditions conditions from from MODE MODE 2 2 conditions conditions in in an an orderly orderly manner manner and and without without challenging plant systems.

challenging plant systems.

BRAIDWOOD UNITS 11 &&22 BRAIDWOOD -- UNITS B B 3.7.2-'§'

3.7.2 --5 Revision Revision .g.4

BASES BASES on an actual or simulated actuation SURVEILLANCE SR 3.7.2.1 signal [from each actuator train]

REQUIREMENTS This This SR SR verifies verifies thatthat MSIV MSIV closure closure time time is is <_

~ 55 seconds.

seconds. TheThe MSIV closure MSIV closure time time is is assumed assumed inin the the accident accident and and containment containment analyses.

analyses. This Surveillance is This Surveillance is normally normally performed performed upon upon returning returning the unit to the unit to operation following aa refueling operation following refueling outage.

outage. Based Based onon ASME Code (Ref.

ASME Code (Ref. 5), the MSIVs 5), the MSIVs are are not not closure time tested closure time tested at at power.

power.

The Frequency is The Frequency is in in accordance accordance with with the the Inservice Inservice Testing Testing Program.

Program. This test is This test is conducted conducted inin MODE MODE 33 with with the the unit unit atat operating temperature and operating temperature and pressure.

pressure. This SR is This SR is modified modified by by aa Note.

Note. This Note allows This Note allows entry entry into into and and operation operation in in MODE MODE 33 prior to prior to performing performing the the SR. This allows SR. This allows aa delay delay ofof testing testing until MODE until MODE 3,3, toto establish conditions consistent establish conditions consistent with with those those under which under which thethe acceptance acceptance criterion criterion was was generated.

generated.

SRSR. 3.7.2.2 3.7.2.2 actuator train can close its respective This This SR SR verifies verifies thatthat each each MSIV MSIV can-eTe5e can close onon an an actual actual oror simulated actuation signal.

simulated actuation signal. This Surveillance is This Surveillance is normally normally performed upon performed upon returning returning the the unit unit to to operation operation following following aa outage. The refueling outage.

refueling Surveillance Frequency The Surveillance Frequency isis controlled controlled under the under the Surveillance Surveillance Frequency Frequency Control Control Program.

Program.

This This SR SR is is modified modified by by aa Note. This Note Note. This Note allows allows entry entry into into and and operation operation in in MODE MODE 33 prior prior toto performing performing thethe SR. This SR. This allows allows aa delay delay ofof testing until MODE testing until MODE 3,3, to to establish establish conditions conditions consistent consistent with those under with those under which which the the acceptance acceptance criterion criterion waswas generated.

generated.

REFERENCES REFERENCES 1. UFSAR, Section UFSAR, Section 10.3.

10.3.

2.

2. UFSAR, Section UFSAR, Section 15.1.5.

15.1.5.

3.

3. UFSAR, Section UFSAR, Section 6.2.6.2.

4.

4. 10 10 CFR 50.67.

CFR 50.67.

5.

5. ASME Code for ASME Code for Operation Operation andand Maintenance Maintenance of of Nuclear Nuclear Power.

Power.

BRAIDWOOD -- UNITS BRAIDWOOD &

UNITS 11 & 22 B 3.7.2-.e B 3.7.2 - 6 Revi si on .gs.

Revision 89,

INSERT A A The MSIV is is a gate gate valve valve with with dual-redundant hydraulic hydraulic actuator actuator trains.

trains. Either Either actuator actuator train can perform the independently perform the safety safety function function to to fast-close fast-close the the MSIV MSIV on on demand.

demand. Each Each actuator train consists of a hydraulic accumulator accumulator controlled controlled by by solenoid solenoid valvesvalves on on thethe associated associated MSIV. MSIV.

each MSIV, For each MSIV, one actuator train is associated with ESF ESF Division Division 1, 1, and and oneone actuator actuator train train is is associated with ESF Division 2.

A pneumatic and hydraulic actuator actuator traintrain is is composed composed solely solely of ofskid-mounted skid-mounted componentscomponents at atthe the MSIV location.

location. The actuator train does not include The actuator train does not include any portion of any portion of the analog channels analog channels or or protection system actuation logic and actuation relays relays that that provide provide inputsinputs to to the the valve valve actuator actuator trains. LCO LCO 3.3.2, 3.3.2, "Engineered Safety Features Actuation System (ESFAS) (ESFAS) Instrumentation,"

Instrumentation,"

provides separate Conditions, Required Actions, and Surveillance provides Surveillance Requirements Requirements for for the the analog analog channels and protection system logic and relays. relays.

INSERT B INSERTB An MSIV actuator train is is considered OPERABLEOPERABLE when when itit isis capable capable of offast-closing fast-closing the the associated MSIV on demand and and within within thethe required required isolation isolation time.time. This This includes includes having having adequate accumulator pressure to support support fast-closure of of the the MSIV MSIV withinwithin thethe required required isolation isolation time.

INSERT C INSERTC A.1 With a single actuator train inoperable on one MSIV, MSIV, action must be taken to restore the inoperable actuator traintrain to OPERABLE status within 7 days. The The7-day 7 -dayCompletion Completion Time Timeisis reasonable in light of of the dual-redundant dual-redundant actuator actuatortrain train design design such such that thatwith withone oneactuator actuatortrain train inoperable, the affected MSIV MSIV is is still still capable capable of ofclosing closing on on demand demandvia viathe theremaining remaining OPERABLE actuator train. train. The The 7-day 7 -dayCompletion Completion Time Timetakes takes into intoaccount accountthe theredundant redundant OPERABLE actuator actuator train to the the MSIV, MSIV, reasonable reasonable time time for for repairs, repairs, and and the thelow lowprobability probabilityofofan an event occurring that requires requires thethe inoperable inoperable actuator actuatortrain train toto the theaffected affectedMSIV. MSIV.

B.1 With one oneactuator actuatortrain train on on one one MSIV MSIVinoperable; inoperable; and and one one actuator actuator train train on on an an additional additional MSIV MSIV inoperable, such that the inoperable inoperable actuator actuator trains trains areare not not inin the the same same ESF ESF Division, Division, action action must be taken to restore one of the inoperable inoperable actuator actuator trains trains to to OPERABLE OPERABLE status status within within 7272 hours0.0842 days 2.02 hours 0.012 weeks 0.00277 months . With one actuator actuator train inoperable inoperable on on twotwo different different MSIVs MSIVs that that are are notnot inin the the same same ESFESF Division, there is an increased likelihood that that an an additional additional failure failure (such (such as as the the failure failure ofof an an actuator logic train) could cause one one MSIVMSIV to to fail fail to to close.

close. The The72-hour 72-hourCompletion CompletionTime Timeisis reasonable since the dual-redundant dual-redundant actuator actuator train train design design ensures ensures that that with with onlyonly one one actuator actuator train on each of of two affected affected MSIVs MSIVs inoperable, inoperable, each each MSIV MSIV is is still still capable capable of ofclosing closing on on demand.

C.1 With With one actuator actuator train train on on one oneMSIVMSIV inoperable; and and oneoneactuator actuatortrain trainon onan anadditional additionalMSIV MSIV inoperable, such thatthat both both inoperable inoperable actuator actuatortrains trains are arein in the the same sameESF ESFDivision, Division, action action must must be taken taken to to restore restoreone oneof ofthe theinoperable inoperableactuator actuatortrains trainstotoOPERABLE OPERABLEstatus statuswithin within 24 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

hours.

The 24-hour 24-hour Completion Time provides a reasonable reasonableamount amountof oftime time for for restoring restoring at at least leastone one

actuator train since the dual-redundant actuator actuator train designdesign forfor each each MSIVMSIVensures ensures thatthataa single inoperable actuator train cannot preventprevent the affected affected MSIV(s)

MSIV(s) from from closing closing on on demand.

demand.

With two actuator trains inoperable in in the the same same ESF ESF Division, Division, an an additional additionalfailure failure(such (suchas asthe the failure of an actuator logic train in the other other ESF Division)

Division) couldcould cause cause both both affected affected MSIVs MSIVsto to demand. The fail to close on demand. The 24 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months hour Completion Completion Time Time takes takes into into the the redundant redundant OPERABLE OPERABLE actuator trains to the affected MSIVs MSIVs and the the low low probability probability of of anan event event occurring occurringthat thatrequires requires the inoperable actuator actuator trains to the affected MSIVs.

MSIVs.

D.1 Required Action D.1 Required D.1 provides assurance that the appropriate Condition Condition is is entered entered forfor the the associated actuator trains affected MSIV if its associated trains become become inoperable.

inoperable. Failure Failure of of both both actuator actuator trains for a single MSIV MSIV results in the inability inability to to close close thethe affected affected MSIVMSIV on on demand.

demand.

E.1 With three or more MSIV actuator trains inoperable inoperable or or when Required Required Action Action A.1, A.1, B.1, B.1, ororC.1C.1 are not completed within the required Completion Time, the affected affected MSIVsMSIVs may maybe be incapable incapableof of closing onon demand demand andand must bebe immediately immediately declared declared inoperable.

inoperable. HavingHaving threethree actuator actuator trains inoperable could involve two inoperable actuator trains on on one one MSIV MSIV and and oneone inoperable inoperable actuator train on another MSIV, or an inoperable actuator actuator traintrain onon each each of of three three MSIVs, MSIVs, for for which the inoperable actuator actuator trains could could all be be inin the the same same ESF ESF Division Division or orbebestaggered staggered among the two ESFESF Divisions.

Divisions.

Depending on which of of these conditions conditions or or combinations combinations isis in in effect, effect, thethecondition conditionor or combination could mean that all all of the affected MSIVs remain capable of closing on on demand (due to the dual-redundant actuator actuator train train design),

design), or or that that at atleast leastoneoneMSIV MSIVisisinoperable, inoperable,or orthat that with an additional single failure up to three MSIVs could be incapable of of closing on on demand.

demand.

cases, immediately declaring the affected MSIVs inoperable is Therefore, in some cases, is conservative (when some or all of the affected MSIVsMSIVs may may still be capable still be capable of ofclosing closingon ondemand demandeven evenwithwithaa single additional failure),

failure), while in in other cases it is appropriate (when (when at least one of the MSIVs would be inoperable, or or up up to to three three could could be be rendered rendered inoperable inoperableby byan anadditional additionalsingle singlefailure).

failure).

Required Required Action E.1E.1 is conservatively based on on the the worst-case worst-case condition condition and andtherefore thereforerequires requires immediately declaring all the affected affected MSIVs MSIVs inoperable.

inoperable.

INSERT D INSERTD Condition F is entered when one MSIV is is inoperable inoperable in in MODE MODE 1, 1, including including when when both both actuator actuator inoperable. When trains for one MSIV are inoperable. When only only one one actuator actuator train train isis inoperable inoperable on on one one MSIV, MSIV, Condition A applies.

ATTACHMENT 55 Byron Station, Proposed Technical Specifications Bases Changes for Byron Station, Units Units 1I and and 22 Byron Byron Station, Units 1I and 22 Facility Operating Operating License Nos.

Nos. NPF -37 and NPF-66 NPF*37 NPF-66 Mark-up of Technical Specifications Specifications Bases Pages 83.7.2-1 B 3.7.2 - 1 83.7.2-3 B 3.7.2 - 3 83.7.2-4 B 3.7.2 - 4 83.7.2-5 B 3.7.2 - 5 83.7.2-6 B 3.7.2 - 6

MSIVs MSIVs B

B 3.7.2 3.7.2 B

B 3.7 PLANT SYSTEMS 3.7 PLANT SYSTEMS B

B 3.7.2 Main Steam 3.7.2 Main Steam Isolation Isolation Valves Valves (MSIVs)

(MSIVs)

BASES BACKGROUND BACKGROUND The The MSIVs isolate steam MSIVs isolate flow from steam flow from the the secondary secondary side side of of the the steam steam generators following aa High generators following High Energy Energy Line Line Break Break (HELB).

(HELB).

MSIV closure terminates MSIV closure terminates flowflow from from the the unaffected unaffected (intact)

(intact) steam generators.

steam generators.

One One MSIV is located MSIV is located in in each each main main steam steam line line outside, outside, but but close to containment.

close to containment. The The MSIVs are downstream MSIVs are downstream from from the the Main Main Steam Safety Valves Steam Safety Valves (MSSVs),

(MSSVs), to to prevent prevent MSSV MSSV isolation isolation from from the the steam steam generators generators by by MSIV MSIV closure. Closing the closure. Closing the MSIVs isolates each MSIVs isolates each steam steam generator generator fromfrom the the others, others, and and isolates isolates the the turbine, turbine, Steam Steam Dump Dump System, and other System, and other auxiliary auxiliary supplies from steam supplies from the the steam steam generators.

generators.

INSERT A The MSIVs MSIVs close close onon aa main main steam steam isolation isolation signal signal generated generated by by Steam Line Low Steam Line Low Pressure, Pressure, Steam Steam Line Line High High Negative Negative Rate, Rate, or or High-2 containment pressure.

High-2 containment pressure. The The MSIVs fail as MSIVs fail as is is on on loss of control loss of control oror actuation actuation power.

power.

Each Each MSIV MSIV has has an an MSIV MSIV bypass bypass valve. Although these valve. Although these bypass bypass valves are valves are normally normally closed, closed, theythey receive receive the the same same automatic automatic closure closure signal signal as as dodo their their associated associated MSIVs. The MSIVs MSIVs. The MSIVs may may also be actuated also be actuated manually.

manually.

A description of A description of the the MSIVs MSIVs is is found found in in the the UFSAR, UFSAR, Section 10.3 (Ref.

Section 10.3 (Ref. 1).1).

UNITS 11 &&22 BYRON -- UNITS BYRON BB 3.7.2 3.7.2 -- -1+/- Revision ~0 Revision

MSIVs MSIVs BB 3.7.2 3.7.2 BASES BASES APPLICABLE APPLICABLE The design The design basis basis of of the the MSIVs MSIVs is is established established by by the the SAFETY ANALYSES SAFETY ANALYSES analysis for analysis for the the large large Steam Steam Line Line Break Break (SLB)

(SLB) outside outside containment, discussed containment, discussed in in the the UFSAR, UFSAR, Section Section 15.1.5 15.1.5 (Ref. 2).

(Ref. 2). It It isis also also affected affected by by the the accident accident analysis analysis of of the SLB the SLB events events presented presented in in the the UFSAR, UFSAR, Section Section 6.26.2 (Ref.

(Ref. 3).3).

The design The design precludes precludes the the blowdown blowdown of of more more than than oneone steam steam generator, assuming generator, assuming aa single single active active component component failure failure (e.g.,

(e.g.,

the failure the failure of one MSIV of one MSIV to to close close on on demand).

demand).

The accident The accident analysis analysis compares compares several several different different SLB SLB events events against different against different acceptance acceptance criteria.

criteria. The The large large SLBSLB outside containment outside containment upstream upstream of of the the MSIV MSIV is is limiting limiting for for dose, although offsite dose, offsite although aa break break in in this this short short section section of of main main steam header steam header hashas a a very very low low probability.

probability. The The large large SLB SLB inside containment inside containment at at hot hot zero zero power power is is the the limiting limiting casecase for aa post for post trip trip return return toto power.

power. The The analysis analysis includes includes scenarios with scenarios offsite power with offsite power available, available, and and with with aa loss loss of of offsite power offsite power following following turbine turbine trip. With offsite trip. With offsite power power available, the available, the reactor reactor coolant coolant pumps pumps continue continue to to circulate circulate through the coolant through coolant the steam steam generators, generators, maximizing maximizing the the Reactor Reactor Coolant System Coolant System (RCS)

(RCS) cooldown.

cool down. With With aa loss loss ofof offsite offsite power, the power, the response response of of mitigating mitigating systems systems isis delayed.

delayed.

Significant single failures Significant single failures considered considered include include failure failure of of anan MSIV to close.

MSIV to close.

The MSIVs serve The MSIVs serve only only aa safety safety function function andand remain remain openopen during power operation.

during power operation. These valves operate These valves operate under under the the following situations:

following situations:

a.

a. An HELB inside An HELB inside containment.

containment. In In order order to to maximize maximize the the mass and energy mass and energy release release into into containment, containment, the the analysis analysis assumes that the assumes that the MSIV MSIV inin the the affected affected steam steam generator generator remains open. For remains open. For this this accident scenario, steam accident scenario, steam is is discharged discharged into into containment containment from from all all steam steam generators generators until until the remaining MSIVs the remaining MSIVs close. After MSIV close. After MSIV closure, closure, steam steam isis discharged discharged intointo containment containment onlyonly from from the the affected steam generator affected steam generator and and from from the the residual residual steam steam in in the the main steam header main steam header downstream downstream of of the the closed closed MSIVs MSIVs inin the the unaffected unaffected loops. Closure of loops. Closure of the the MSIVs MSIVs isolates isolates the the break break from from thethe unaffected unaffected steam steam generators.

generators.

BYRON UNITS 11 &&22 BYRON -- UNITS B B 3.7.2 3.7.2 -- 2 2 Revision Revision 0 0

MSIVs MSIVs B

B 3.7.2 3.7.2 BASES BASES APPLICABLE SAFETY ANALYSES APPLICABLE SAFETY ANALYSES (continued)

(continued) b.

b. A break outside A break outside of of containment containment and and upstream upstream from from thethe MSIVs is not MSIVs is not aa containment containment pressurization pressurization concern.

concern.

The uncontrolled blowdown The uncontrolled blowdown of of more more than than one one steam steam generator generator must be prevented must be prevented to to limit limit the the potential potential for for uncontrolled uncontrolled RCSRCS cooldown cooldown and and positive positive reactivity reactivity addition.

addition. Closure Closure ofof the the MSIVs isolates the MSIVs isolates the break break andand limits limits the blowdown to the blowdown to aa single single steam steam generator.

generator.

c.

c. A break downstream A break downstream of of the the MSIVs MSIVs will will be be isolated isolated by by the closure of the closure of the the MSIVs.

MSIVs.

d.

d. Following Following a a steam steam generator generator tubetube rupture, rupture, closure closure of of the the MSIVs isolates the MSIVs isolates the ruptured ruptured steam steam generator generator from from the intact steam the intact steam generators generators to to minimize minimize radiological radiological releases.

releases.

e.

e. The The MSIVs are also MSIVs are also utilized utilized during during other other events events such such as as aa feedwater feedwater line line break. This event break. This event isis less less limiting limiting soso far far as as MSIV MSIV OPERABILITY OPERABILITY is is concerned.

concerned.

The MSIVs satisfy The MSIVs satisfy Criterion Criterion 33 of of 10 10 CFR CFR 50.36(c)(2)(ii).

50.36(c)(2)(ii). and their associated actuator LCO LCO This LCO requires This LCO requires that that four four MSIVsfin MSIVs in thethe steam steam lines lines bebe treons OPERABLE.

OPERABLE. The MSIVs are The MSIVs are considered considered OPERABLE OPERABLE whenwhen the the isolation times isolation times are are within limits, and within limits, and they they close close onon an an isolation actuation signal.

isolation actuation signal.

NSERT B B I---~

1.....-_ _- - - ' Thi Thiss LCO LCO provides provi des assurance assurance thatthat the the MSIVs MSIVs will wi 11 perform perform their design safety their design safety function function to to mitigate mitigate thethe consequences consequences of of accidents that accidents that could could result result in in exposures exposures comparable comparable to to the the 10 10 CFR 50.67 (Ref.

CFR 50.67 (Ref. 4)4) limits limits or or the the NRC NRC staff staff approved approved licensing basis.

licensing basis.

BYRON -- UNITS BYRON &

UNITS 11 & 22 B 3.7.2 B 3.7.2 -- -33 Revi s ion .§.5.

Revision

MSIVs MSIVs B

B 3.7.2 3.7.2 and required BASES BASES actuator trains APPLICABI LITY APPLICABILITY The The MSIVs must be MSIVsTmust be OPERABLE OPERABLE inin MODE MODE 1, 1, and and in in MODES MODES 22 and and 33 except except when when closed, closed, when when there is significant there is significant massmass and and energy energy in in the the RCS RCS and and steam steam generators.

generators. When When the the MSIVs MSIVs are are closed, closed, theythey are are already already performing performing the the safety safety function.

function. In In MODE MODE 4 4 the the steam steam generator generator energy energy is is low.

low.

In In MODE MODE 5 or 6, 5 or 6, the steam generators the steam generators do do not not contain contain much much energy because their energy because their temperature temperature is is below below the the boiling boiling point point of of water; therefore, the water; therefore, the MSIVs MSIVs are are notnot required required forfor isolation isolation of of potential potential highhigh energy energy secondary secondary system system pipe pipe breaks in breaks in these these MODES.

MODES.

ERT C ACTIONS ACTIONS .4.

With With one one MSIV MSIV inoperable inoperable in in MODE MODE 1,1, action action must must bebe taken taken toto restore OPERABLE restore OPERABLE status status within within 8 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

hours. SomeSome repairs repairs to to the the MSIV MSIV can can be be made made with with the the unit unit hot.

hot. The The 88hour hour Completion Completion Time Time is is reasonable, reasonable, considering considering the the low low probability probability of of an an accident occurring during accident occurring during this this time time period period that that would would requirere aa closure closure of of the the MSIVs.

MSIVs.

INSERT D The 8 hour Completion 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months Completion TimeTime is is greater greater thanthan that that normally normally allowed for containment allowed for containment isolation isolation valves valves because because the the MSIVs MSIVs are are valves that isolate valves that isolate aa closed closed system system penetrating penetrating containment.

containment. These valves differ These valves differ from from other other containment containment isolation valves in isolation valves in that that the the closed closed system system provides provides an an additional means for additional means for containment containment isolation.

isolation .

.g.. 1 If If the the MSIV MSIV cannot cannot bebe restored restored toto OPERABLE OPERABLE statu within statu within hours, the 88 hours0.00102 days 0.0244 hours 1.455026e-4 weeks 3.3484e-5 months , the unit unit must must bebe placed placed inin aa MODE MODE in in which wh ch the the LCO LCO does does not not apply.

apply. ToTo achieve achieve this this status, status, th th nitnit must must be placed be placed inin MODE MODE 22 within within 66 hours7.638889e-4 days 0.0183 hours 1.09127e-4 weeks 2.5113e-5 months hours andand Condition Condition ~ would would bebe entered.

entered. The Completion Time The Completion Time is is reasonable, reasonable, basedbased onon operating experience, to operating experience, to reach reach MODE MODE 22 andand to to close close the the MSIVs MSIVs in in anan orderly orderly manner and without manner and without challenging challenging plantplant systems.

systems.

BYRON UNITS 11 &&22 BYRON -- UNITS B B 3.7.2-4 3.7.2 - 4 Revision Revision -G .g.

MSIVs MSIVs B

B 3.7.2 3.7.2 BASES BASES ACTIONS (continued)

ACTIONS (continued) ;----1

-G.1 and -G.2 Condition Condition tE isis modified modified by by aa Note Note indicating indicating that that separate separate Condition entry is Condition entry is allowed allowed forfor each each MSIV.

MSIV.

Since Since the the MSIVs are required MSIVs are required to to be be OPERABLE OPERABLE in in MODES MODES 22 and and 3,3, the inoperable MSIVs the inoperable MSIVs may may either either bebe restored restored toto OPERABLE status or OPERABLE status or closed.

closed. When closed, the When closed, the MSIVs MSIVs areare already already inin the the position position required required by by the the assumptions assumptions in in the the safety analysis.

safety analysis.

The The 8 B hour hour Completion Completion Time Time isis consistent consistent with with that that allowed allowed in Condition A=E----[]

in Condition # F For For inoperable inoperable MSIVs MSIVs that cannot be that cannot be restored restored toto OPERABLE OPERABLE status status within the specified within the specified Completion Completion Time, Time, but but are are closed, closed, the inoperable MSIVs the inoperable MSIVs must must be be verified verified onon aa periodic periodic basis basis toto be closed.

be closed. This This isis necessary necessary to to ensure ensure that that the the assumptions assumptions in in the the safety safety analysis analysis remain remain valid. The 77 day valid. The day Completion Completion Time Time isis reasonable, reasonable, based based onon engineering engineering judgment, judgment, in in view view of of MSIV status indications MSIV status indications available available in in the the control control room, room, and and other administrative controls, other administrative controls, to to ensure ensure that that these these

~es valves :re in the are in the closed closed position.

position.

- ~ft.1~ft.2 If If the the MSIVs MSIVs cannot cannot be restored to be restored to OPERABLE status or OPERABLE status or are are not closed within not closed the associated within the associated Completion Completion Time, Time, the the unit unit must must bebe placed placed inin aa MODE MODE inin which which the the LCO LCO does does not not apply.

apply.

To achieve this To achieve this status, status, thethe unit unit must must bebe placed placed atat least least inin MODE MODE 3 3 within within 6 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months , hours, and and inin MODE MODE 44 within within 1212 hours0.014 days 0.337 hours 0.002 weeks 4.61166e-4 months .

hours. TheThe allowed allowed Completion Times are Completion Times are reasonable, reasonable, based based onon operating operating experience, experience, to reach the to reach the required required unit unit conditions conditions from from MODE MODE 2 2 conditions conditions in in an an orderly orderly manner manner and and without without challenging plant systems.

challenging plant systems.

BYRON UNITS 11 &&22 BYRON -- UNITS B 3.7.2-'§'

B 3.7.2 - -5 Revision Revision .g.

f

MSIVs MSIVs B

B 3.7.2 3.7.2 BASES BASES Ion an actual or simulate d actuation SURVEI LLANCE SURVEILLANCE SR 372

. . .1 signal [from each actuator train]

REQUIREMENTS REQUIREMENTS This This SRSR verifies verifies thatthat MSIV MSIV closure closure time time is is <_

~ 55 seconds.

seconds. TheThe MSIV closure time MSIV closure time is is assumed assumed inin the the accident accident and and containment containment analyses.

analyses. This Surveillance is This Surveillance is normally normally performed performed upon upon returning the returning the unit unit to to operation operation following following aa refueling refueling outage.

outage. Based Based on on ASME Code (Ref.

ASME Code (Ref. 5),

5), the the MSIVs MSIVs are are not not closure time tested closure time tested at at power.

power.

The Frequency is The Frequency is in in accordance accordance with with the the Inservice Inservice Testing Testing Program.

Program. This test is This test is conducted conducted inin MODE MODE 33 with with the the unit unit atat operating temperature and operating temperature and pressure.

pressure. This SR is This SR is modified modified by by aa Note.

Note. This Note allows This Note allows entry entry into into and and operation operation inin MODE MODE 33 prior to prior to performing performing the the SR. This allows SR. This allows aa delay delay ofof testing testing until MODE until 3, to MODE 3, to establish conditions consistent establish conditions consistent with with those those under which under which the the acceptance acceptance criterion criterion waswas generated.

generated.

SR 3.7.2.2 actuator train can close its respective This This SRSR verifies verifies that that each each MSIV MSIV ecan fl close eTe on an actual on an actual or or simulated actuation signal.

simulated actuation signal. This Surveillance is This Surveillance is normally normally performed upon performed upon returning returning thethe unit unit toto operation operation following following aa refueling outage. The refueling outage. The Surveillance Frequency is Surveillance Frequency is controlled controlled under the under the Surveillance Surve; 11 ance Frequency Frequency Control Control Program.

Program.

This This SRSR is is modified modified by by aa Note. This Note Note. This Note allows allows entry entry into into and and operation operation in in MODE MODE 3 3 prior prior toto performing performing thethe SR. This SR. This allows allows aa delay delay of of testing testing until until MODE MODE 3, to establish 3, to establish conditions consistent with conditions consistent those under with those under which the acceptance which the acceptance criterion was generated.

criterion was generated.

REFERENCES REFERENCES 1. UFSAR, Section UFSAR, Section 10.3.

10.3.

2.

2. UFSAR, Section UFSAR, Section 15.1.5.

15.1.5.

3.

3. UFSAR, Section UFSAR, Section 6.2.

6.2.

4.

4. 10 CFR 10 50.67.

CFR 50.67.

5.

5. ASME Code for ASME Code for Operation Operation and and Maintenance Maintenance of of Nuclear Nuclear Power Plants.

Power Plants.

BYRON UNITS 11 &&22 BYRON -- UNITS 83.7.2- B 3.7.2 - 6 Revi si on Revision ::p;j

INSERT A A The MSIV MSIV is a gate valve with dual-redundant hydraulic actuator trains. Either Eitheractuator actuatortrain train can can independently perform the safety function to fast-close the MSIV on demand. Each actuator Each actuator train consists consists of of aa hydraulic hydraulic accumulator accumulator controlled controlled by by solenoid solenoid valves valveson onthetheassociated associatedMSIV. MSIV.

For each MSIV, one actuator actuator train is is associated associated with with ESF ESF Division Division 1, 1, and and one oneactuator actuatortraintrainisis associated with ESF ESF Division Division 2.

2.

A pneumatic pneumatic and and hydraulic hydraulic actuator actuator train is is composed solely solely of skid-mounted components at at the the MSIV MSIV location.

location. The Theactuator actuatortrain traindoes doesnot notinclude includeany anyportion portion of of the the analog analog channels channels or or protection system actuation logic and actuation actuation relays relays that that provide provide inputs inputs to to the thevalve valveactuator actuator 3.3.2, "Engineered Safety trains. LCO 3.3.2, Safety Features FeaturesActuation Actuation SystemSystem (ESFAS) Instrumentation,"

provides separate Conditions, Conditions, Required Required Actions, Actions, and and Surveillance Surveillance Requirements Requirementsfor forthe theanalog analog channels andand protection protection system system logic logic and and relays.

relays.

INSERT B B An MSIV actuator actuator train is is considered considered OPERABLE OPERABLE when when itit isis capable capable of offast-closing fast-closingthe the associated MSIV on demand demand and and within within the required required isolation isolation time.

time. This This includes includes having having adequate accumulator pressurepressure to support support fast-closure fast-closure of of the the MSIV MSIVwithinwithin the the required required isolation isolation time.

INSERTC INSERT C A.1 With a single actuator train train inoperable on one MSIV, action must be taken to restore the inoperable actuator train to OPERABLE status within 7 days. The The7-day 7-dayCompletion CompletionTime Timeisis reasonable in light of the dual-redundant dual-redundant actuator actuator train train design design such suchthat thatwith withoneoneactuator actuatortrain train inoperable, inoperable, the affected MSIV is still capable of closing on demand via the remaining OPERABLE actuator train. The 7-day train. The 7-dayCompletion Completion Time Timetakestakesintointoaccount accountthe theredundant redundant OPERABLE actuator train to the MSIV, MSIV, reasonable time for repairs, and the lowprobability reasonable time for repairs, and the low probabilityofofan an event occurring that requires the the inoperable inoperable actuator actuatortrain train to to the the affected affectedMSIV. MSIV.

B.1 With one one actuator actuator train train on on one one MSIV MSIV inoperable; inoperable; and and oneone actuator actuator traintrain on on anan additional additional MSIV MSIV inoperable, such that the inoperable actuator trains are not inoperable, not in the samesame ESF ESF Division, Division, action action must be taken to restore one of the inoperable actuator actuator trains to OPERABLE status status within within 72 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . With one actuator train inoperable on two different different MSIVsMSIVs that that are are not not in in the the same same ESF ESF Division, there is an increased likelihood that an additional failure (such Division, (such as as the the failure failure ofof anan train) could actuator logic train) could cause cause one one MSIV MSIV to to fail fail to to close.

close. The 72-hour 72-hour Completion Completion Time is is reasonable since the dual-redundant actuator train design ensures ensures that that with with only only one one actuator actuator train on each of two affected MSIVs inoperable, inoperable, each each MSIV MSIV is is still still capable capable of ofclosing closing on on demand.

C.1 With one actuator train on one MSIV inoperable; and one actuator With actuator traintrain on on anan additional additional MSIV MSIV inoperable, such inoperable, such that both inoperable actuator trains are in the same ESF ESF Division, Division, action action must must be taken to restore one of the inoperable actuator trains to OPERABLE status status within within 24 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

hours.

The 24-hour Completion Time provides a reasonable amount amount of of time time forfor restoring restoring at at least leastone one

actuator train since the dual-redundant actuator actuator train design design forfor each each MSIV MSIV ensures ensures that that aa single inoperable actuator train cannot prevent prevent the affected affected MSIV(s)

MSIV(s) from from closing closing onon demand.

demand.

With two actuator trains inoperable in the same same ESF ESF Division, Division, an an additional additional failure failure (such (such as as the the failure of an actuator logic train in the otherother ESFESF Division)

Division) couldcould cause cause both both affected affected MSIVs MSIVs to to fail to close fail close on on demand.

demand. The The 2424 hour0.0281 days 0.673 hours 0.00401 weeks 9.22332e-4 months hour Completion Completion Time Time takestakes into into the the redundant redundant OPERABLE OPERABLE actuator trains to the affected MSIVs and the low low probability probability of of an an event event occurring occurring that that requires requires the inoperable actuator actuator trains to the affected affected MSIVs.

MSIVs.

D.1 Required Action D.1 Required D.1 provides assurance that the appropriate Condition Condition is is entered entered forfor the the affected MSIV if its affected its associated associated actuator actuator trains trains become become inoperable.

inoperable. Failure Failure of of both actuator actuator trains for a single MSIV results in in the inability inability to close close the the affected affected MSIVMSIV on on demand.

demand.

E.1 With three or more MSIV actuator actuator trains trains inoperable inoperable or or when when Required Required Action Action A.1, A.1, B.1, B.1, oror C.1 C.1 are not completed within the required CompletionCompletion Time, Time, the the affected affected MSIVsMSIVs may may bebe incapable incapable of of closing on demand closing demand andand must be immediately declared declared inoperable.

inoperable. HavingHaving threethree actuator actuator trains inoperable could involve two inoperable actuator actuator trains trains on on one one MSIV MSIV and and oneone inoperable inoperable actuator train on another MSIV, or or an inoperable inoperable actuator actuator traintrain on on each each of of three three MSIVs, MSIVs, for for which the inoperable actuator actuator trains couldcould allall be be in in the the same same ESF ESF Division Division or or be be staggered staggered among the two ESF Divisions.

which of these conditions or combinations is in effect, the condition or Depending on which combination could mean that all of the affected MSIVs remain capable of closing on demand (due to the dual-redundant actuator train design), or that at least one MSIV is inoperable, or that with an additional single failure up to three MSIVs could be incapable incapable of of closing closing on on demand.

Therefore, in some cases, immediately declaring the affected MSIVs MSIVs inoperable is conservative (when some or all of the affected MSIVs may still be capable of closing on demand even with a (when single additional failure), while in in other other cases cases itit isis appropriate appropriate (when (whenat atleast leastoneoneofofthe theMSIVs MSIVs would be inoperable, or or up up to to three three could could be be rendered rendered inoperable inoperableby byan anadditional additionalsingle singlefailure).

failure).

Required Action E.1E.1 is conservatively conservatively based based on on the the worst-case worst-casecondition conditionand andtherefore thereforerequires requires immediately declaring all the affected affected MSIVs MSIVs inoperable.

inoperable.

INSERT D 0 Condition F is entered when one MSIV MSIV is is inoperable inoperable in in MODE MODE 1, 1, including including when when both both actuator actuator trains for one MSIV are inoperable.

MSIV are inoperable. When only one actuator actuator train is is inoperable inoperable on on one one MSIV, MSIV, Condition A applies.

applies.

RS-13-175, Bryon, Units 1 and 2, License Amendment Request to Revise Technical Specifications Section 3.7.2, Main Steam Isolation Valves (Msivs).

Contents

Text

Subject:

Reference:

Subject:

SUMMARY

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

SUMMARY

SUMMARY

3.0 TECHNICAL EVALUATION

Background

4.0 REGULATORY EVALUATION

Response

Response

6.0 REFERENCES

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RS-13-175, Bryon, Units 1 and 2, License Amendment Request to Revise Technical Specifications Section 3.7.2, Main Steam Isolation Valves (Msivs).

Text

Subject:

Reference:

Subject:

SUMMARY

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

SUMMARY

SUMMARY

3.0 TECHNICAL EVALUATION

Background

4.0 REGULATORY EVALUATION

Response

Response

6.0 REFERENCES

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