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{{Adams
#REDIRECT [[BVY 15-024, Revision of Technical Specifications Bases Pages]]
| number = ML15086A451
| issue date = 03/25/2015
| title = Vermont Yankee, Revision of Technical Specifications Bases Pages
| author name = Chappell C C
| author affiliation = Entergy Nuclear Operations, Inc
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000271
| license number = DPR-028
| contact person =
| case reference number = BVY 15-024, TAC MF3068
| document type = Letter, Technical Specification, Bases Change
| page count = 8
| project = TAC:MF3068
| stage = Other
}}
 
=Text=
{{#Wiki_filter:SEntergyEntergy Nuclear Operations, Inc.Vermont Yankee320 Governor Hunt RdVernon, VT 05354Tel 802 257 7711Coley C. ChappellLicensing ManagerBVY 15-024March 25, 2015ATTN: Document Control DeskU.S. Nuclear Regulatory Commission Washington, DC 20555
 
==SUBJECT:==
 
==REFERENCE:==
 
Revision of Technical Specifications Bases PagesVermont Yankee Nuclear Power StationDocket No. 50-271License No. DPR-28Letter, USNRC to Entergy Nuclear Operations, Inc., "Vermont YankeeNuclear Power Station -Issuance of Amendment to Renewed FacilityOperating License RE: Eliminate Operability Requirements for Secondary Containment when Handling Sufficiently Decayed Irradiated Fuel or a FuelCask (TAC NO. MF3068),"
NVY 15-013, dated February 12, 2015(ML14304A588)
 
==Dear Sir or Madam:==
This letter provides revised Vermont Yankee Nuclear Power Station (VYNPS) Technical Specification (TS) Bases pages. The TS Bases were revised in conjunction with an Amendment toRenewed Facility Operating License DPR-28 issued in the referenced letter.These changes, processed in accordance with our Technical Specification Bases Control Program(TS 6.7.E), were determined not to require prior NRC approval.
The revised Bases pages areprovided for your information and for updating and inclusion with your copy of the VYNPS TS. NoNRC action is required in conjunction with this submittal.
There are no new regulatory commitments being made in this submittal.
Should you have any questions concerning this submittal, please contact me at 802-451-3374.
Sincerely, Ccc/lAcc BVY 15-024 / Page 2 of 2
 
==Attachment:==
: 1. Revised Technical Specifications Bases Pages (5 pages)cc: Mr. Daniel H. DormanRegional Administrator, Region 1U.S. Nuclear Regulatory Commission 2100 Renaissance Blvd, Suite 100King of Prussia, PA 19406-2713 Mr. James S. Kim, Project ManagerDivision of Operating Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop 08D15Washington, DC 20555USNRC Resident Inspector Mr. Christopher
: Recchia, Commissioner VT Department of Public Service112 State Street -Drawer 20Montpelier, Vermont 05620-2601 BVY 15-024Docket No. 50-271Attachment 1Vermont Yankee Nuclear Power StationRevised Technical Specifications Bases Pages (5 pages)
VYNPSBASES: 3.2.C/4.2.C REACTOR BUILDING VENTILATION ISOLATION AND STANDBY GASTREATMENT SYSTEM INITIATION APPLICABLE SAFETY ANALYSES, LCO, and APPLICABILITY (continued) instrumentation are implicitly assumed in the safety analyses of References 2,3, and 4, to initiate closure of the RBAVSIVs and start the SGT System to limitoffsite doses.Reactor building ventilation isolation and Standby Gas Treatment Systeminitiation instrumentation satisfies Criterion 3 of 10 CFR 50.36(c)
(2) (ii).The operability of the reactor building ventilation isolation and Standby GasTreatment System initiation instrumentation is dependent on the operability ofthe individual instrumentation channel Trip Functions specified in Table 3.2.3.Each Trip Function must have the required number of operable channels in eachtrip system, with their trip setpoints within the calculational as-foundtolerances specified in plant procedures.
Operation with actual trip setpoints within calculational as-found tolerances provides reasonable assurance that,under worst case design basis conditions, the associated trip will occur withinthe Trip Settings specified in Table 3.2.3. As a result, a channel isconsidered inoperable if its actual trip setpoint is not within thecalculational as-found tolerances specified in plant procedures.
The actualtrip setpoint is calibrated consistent with applicable setpoint methodology assumptions.
In general, the individual Trip Functions are required to be OPERABLE in RUN,STARTUP/HOT
: STANDBY, HOT SHUTDOWN, Refuel (with reactor coolant temperature
> 212'F), during operations with the potential for draining the reactor vessel(OPDRVs) and during movement of recently irradiated fuel assemblies insecondary containment, and during Alteration of the Reactor Core; consistent with the Applicability for the SGT System and secondary containment requirements in Specifications 3.7.B and 3.7.C. Trip Functions that havedifferent Applicabilities are discussed below in the individual Trip Functions discussion.
"Recently irradiated" fuel is defined as fuel that has occupied part of acritical reactor core within the previous 13 days, i.e. reactor fuel thathas decayed less than 13 days following reactor shutdown.
This minimumdecay period is enforced to maintain the validity of the Fuel HandlingAccident dose consequence analysis.
The specific Applicable Safety Analyses, LCO, and Applicability discussions arelisted below on a Trip Function by Trip Function basis.1. Low Reactor Vessel Water LevelLow reactor pressure vessel (RPV) water level indicates that the capability tocool the fuel may be threatened.
Should RPV water level decrease too far, fueldamage could result. An isolation of the secondary containment and actuation of the SGT System are initiated in order to minimize the potential of anoffsite release.
The Low Reactor Vessel Water Level Trip Function is one ofthe Trip Functions assumed to be operable and capable of providing isolation and initiation signals.
The isolation and initiation of systems on Low ReactorVessel Water Level support actions to ensure that any offsite releases arewithin the limits calculated in the safety analysis.
Low Reactor Vessel Water Level signals are initiated from level transmitters that sense the difference between the pressure due to a constant column ofwater (reference leg) and the pressure due to the actual water level (variable leg) in the vessel. Four channels of Low Reactor Vessel Water Level TripFunction are available and are required to be operable to ensure that no singleinstrument failure can preclude the isolation and initiation function.
Amendment No. 2-34, 26276p VYNPSBASES: 3.2.C/4.2.C REACTOR BUILDING VENTILATION ISOLATION AND STANDBY GASTREATMENT SYSTEM INITIATION APPLICABLE SAFETY ANALYSES, LCO, and APPLICABILITY (continued) have originated from the primary containment due to a break in the RCPB or therefueling floor due to a fuel handling accident.
When High Reactor BuildingVentilation Radiation or High Refueling Floor Zone Radiation is detected, secondary containment isolation and actuation of the SGT System are initiated to support actions to limit the release of fission products as assumed in theUFSAR safety analyses (Ref. 4).The High Reactor Building Ventilation Radiation and High Refueling Floor ZoneRadiation signals are initiated from radiation detectors that are located onthe ventilation exhaust duct coming from the reactor building and the refueling floor zones, respectively.
Two channels of High Reactor Building Ventilation Radiation Trip Function and two channels of High Refueling Floor Radiation TripFunction are available and are required to be operable to ensure that no singleinstrument failure can preclude the isolation and initiation function.
The Trip Settings are chosen to promptly detect gross failure of the fuelcladding.
The High Reactor Building Ventilation Radiation and High Refueling Floor ZoneRadiation Trip Functions are required to be operable in RUN, STARTUP/HOT
: STANDBY, HOT SHUTDOWN, Refuel (with reactor coolant temperature
> 212'F) whereconsiderable energy exists in the RCS; thus, there is a possibility of pipebreaks resulting in significant releases of radioactive steam and gas. In COLDSHUTDOWN and Refuel (with reactor coolant temperature
< 212'F), the probability and consequences of these events are low due to the RCS pressure andtemperature limitations of these Modes; thus, these Trip Functions are notrequired.
In addition, the Trip Functions are also required to be operableduring OPDRVs and during movement of recently irradiated fuel assemblies in thesecondary containment, and during Alteration of the Reactor Core, because thecapability of detecting radiation releases due to fuel failures (due to fueluncovery or dropped fuel assemblies) must be provided to ensure that offsitedose limits are not exceeded.
"Recently irradiated" fuel is defined as fuel that has occupied part of acritical reactor core within the previous 13 days, i.e. reactor fuel thathas decayed less than 13 days following reactor shutdown.
This minimumdecay period is enforced to maintain the validity of the Fuel HandlingAccident dose consequence analysis.
ACTIONSTable 3.2.3 ACTION Note 1Because of the diversity of sensors available to provide isolation signals andthe redundancy of the isolation design, an allowable out of service time of12 hours or 24 hours depending on the Trip Function (12 hours for those TripFunctions that have channel components common to RPS instrumentation, i.e.,Trip Functions 1 and 2, and 24 hours for those Trip Functions that do not havechannel components common to RPS instrumentation, i.e., all other TripFunctions),
has been shown to be acceptable (Refs. 5 and 6) to permitrestoration of any inoperable channel to operable status. This out of servicetime is only acceptable provided the associated Trip Function is stillmaintaining isolation capability (refer to next paragraph).
If the inoperable channel cannot be restored to operable status within the allowable out ofservice time, the channel must be placed in the tripped condition per Table3.2.3 Note l.a.l) or l.a.2), as applicable.
Placing the inoperable channel intrip would conservatively compensate for the inoperability, restore capability to accommodate a single failure, and allow operation to continue.
Alternately, Amendment No. 2-34, 26276r VYNPSBASES: 3.7 (Cont'd)surveillances such as monthly torus to drywell vacuum breaker tests.Procedurally, when AC-6A is open, AC-6 and AC-7 are closed to preventoverpressurization of the SBGT system or the reactor building
: ductwork, should a LOCA occur. For this and similar analyses performed, aspurious opening of AC-6 or AC-7 (one of the closed containment isolation valves) is not assumed as a failure simultaneous with apostulated LOCA. Analyses demonstrate that for normal plant operation system alignments, including surveillances such as those described above, that SBGT integrity would be maintained if a LOCA waspostulated.
Therefore, during normal plant operations, the 90 hourclock does not apply. Accordingly, opening of the 18 inch atmospheric control isolation valves AC-7A, AC-7B, AC-8 and AC-10 will be limitedto 90 hours per calendar year (except for performance of the subjectvalve stroke time surveillances
-in which case the appropriate corresponding valves are closed to protect equipment should a LOCAoccur). This restriction will apply whenever primary containment integrity is required.
The 90 hour clock will apply anytime purge andvent evolutions can not assure the integrity of the SBGT trains orrelated equipment.
B. and C. Standby Gas Treatment System and Secondary Containment SystemThe secondary containment is designed to minimize any ground levelrelease of radioactive materials which might result from a seriousaccident.
The Reactor Building provides secondary containment duringreactor operation, when the drywell is sealed and in service; theReactor Building provides primary containment when the reactor isshutdown and the drywell is open, as during refueling.
Because thesecondary containment is an integral part of the complete containment system, secondary containment is required at all times that primarycontainment is required except, however, for initial fuel loading andlow power physics testing.In the Cold Shutdown condition or the Refuel Mode, the probability andconsequences of the LOCA are reduced due to the pressure andtemperature limitations in these conditions.
Therefore, maintaining Secondary Containment Integrity is not required in the Cold Shutdowncondition or the Refuel Mode, except for other situations for whichsignificant releases of radioactive material can be postulated, such asduring operations with a potential for draining the reactor vessel,during alteration of the Reactor Core, or during movement of recentlyirradiated fuel assemblies in the secondary containment.
"Recently irradiated" fuel is defined as fuel that has occupied part ofa critical reactor core within the previous 13 days, i.e. reactor fuelthat has decayed less than 13 days following reactor shutdown.
Thisminimum decay period is enforced to maintain the validity of the FuelHandling Accident dose consequence analysis.
In order for secondary containment integrity to be met, the secondary containment must function properly in conjunction with the operation ofthe Standby Gas Treatment System to ensure that the required vacuum canbe established and maintained.
This means that the reactor building isintact with at least one door in each access opening closed, and allreactor building automatic ventilation system isolation valves areoperable or the affected penetration flow path is isolated.
With the reactor in the Run Mode, the Startup Mode, or the Hot Shutdowncondition, if Secondary Containment Integrity is not maintained, Secondary Containment Integrity must be restored within 4 hours. The4 hours provides a period of time to correct the problem that iscommensurate with the importance of maintaining secondary containment during the Run Mode, the Startup Mode, and the Hot Shutdown condition.
This time period also ensures that the probability of an accident(requiring Secondary Containment Integrity) occurring during periodswhere Secondary Containment Integrity is not maintained, is minimal.Amendment No. 4-, 4-43, 4-44, 4-6-, 4-9-4, 262165a VYNPSBASES: 3.7 (Cont'd)If Secondary Containment Integrity cannot be restored within therequired time period, the plant must be brought to a mode or condition in which the LCO does not apply.Movement of recently irradiated fuel assemblies in the secondary containment, alteration of the Reactor Core, and operations with thepotential for draining the reactor vessel can be postulated to causefission product release to the secondary containment.
In such cases,the secondary containment is the only barrier to release of fissionproducts to the environment.
Alteration of the Reactor Core andmovement of recently irradiated fuel assemblies must be immediately suspended if Secondary Containment Integrity is not maintained.
Suspension of these activities shall not preclude completing an actionthat involves moving a component to a safe position.
Also, action mustbe immediately initiated to suspend operations with the potential fordraining the reactor vessel to minimize the probability of a vesseldraindown and subsequent potential for fission product release.Actions must continue until operations with the potential for drainingthe reactor vessel are suspended.
Amendment No. 4-4-3, 4-44, 4-64-, 262165b VYNPSBASES: 3.7 (Cont'd)The Standby Gas Treatment System (SGTS) is designed to filter andexhaust the Reactor Building atmosphere to the stack during secondary containment isolation conditions, with a minimum release of radioactive materials from the Reactor Building to the environs.
To insure thatthe standby gas treatment system will be effective in removingradioactive contaminates from the Reactor Building air, the system istested periodically to meet the intent of ANSI N510-1975.
Laboratory charcoal testing will be performed in accordance with ASTM D3803-1989, except, as allowed by GL 99-02, testing can be performed at 70%relative humidity for systems with humidity control.
Both standby gastreatment fans are designed to automatically start upon containment isolation and to maintain the Reactor Building pressure toapproximately a negative 0.15 inch water gauge pressure; all leakageshould be in-leakage.
Should the fan fail to start, the redundant alternate fan and filter system is designed to start automatically.
Each of the two fans has 100% capacity.
This substantiates theavailability of the operable train and results in no added risk; thus,reactor operation or refueling operation can continue.
If neithertrain is operable, the plant is brought to a condition where the systemis not required.
When the reactor is in cold shutdown or refueling the drywell may beopen and the Reactor Building becomes the only containment system.During cold shutdown the probability and consequences of a DBA LOCA aresubstantially reduced due to the pressure and temperature limitations in this mode. However, for other situations under which significant radioactive release can be postulated, such as during operations with apotential for draining the reactor vessel, during core alterations, orduring movement of recently irradiated fuel in the secondary containment, operability of standby gas treatment is required.
Both trains of the Standby Gas Treatment System are normally operablewhen secondary containment integrity is required.
However,Specification 3.7.B.3 provides Limiting Conditions for Operation whenone train of the Standby Gas Treatment System is inoperable.
Provisional, continued operation is permitted since the remaining operable train is adequate to perform the required radioactivity release control function.
If the applicable conditions ofSpecification 3.7.B.3 cannot be met, the plant must be placed in a modeor condition where the Limiting Conditions for Operation do not apply.Entry into a refueling condition with one train of SBGTS inoperable isacceptable and there is no prohibition on mode or condition entry inthis situation.
In this case, the requirements of TS 3.7.B.3.b aresufficient to ensure that adequate controls are in place. Duringrefueling conditions, accident risk is significantly
: reduced, and theprimary activities of concern involve core alterations, movement ofrecently irradiated fuel assemblies and OPDRVs.During refueling and cold shutdown conditions Specification 3.7.B.3.b provides for the indefinite continuance of refueling operations withone train of the Standby Gas Treatment System inoperable.
When theseven-day completion time associated with Specification 3.7.B.3.b isnot met and secondary containment integrity is required, the operabletrain of the Standby Gas Treatment System should immediately be placedinto operation.
This action ensures that the remaining train isoperable, that no failures that could prevent automatic actuation haveoccurred, and that any other failure would be readily detected.
Analternative to placing the operable train of Standby Gas Treatment inoperation is to immediately suspend activities that represent apotential for releasing radioactive material to the secondary containment, thus placing the plant in a condition that minimizes risk.Amendment No. 4-&, 4-9, 4-4-3, 4-94, 262166}}

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