ML18179A251
| ML18179A251 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 06/15/2018 |
| From: | Southern Nuclear Operating Co |
| To: | Office of New Reactors |
| Shared Package | |
| ML18179A227 | List:
|
| References | |
| ND-18-0656 | |
| Download: ML18179A251 (55) | |
Text
VOGTLE UNITS 3 AND 4 TECHNICAL REQUIREMENTS MANUAL (TRM)
List of Effective Sections VEGP Units 3 and 4 Page 1 of 1 Revision 7 Note that all TRM pages for a TRM Section are shown with same revision when any change to that Section is made. Revision Bars show the specific change locations.
TRM Section Revision Table of Contents 2
TRM 1.1 0
TRM 1.2 0
TRM 1.3 0
TRM 1.4 0
TRM 3.0 0
TRM 3.3.1 3
TRM 3.3.2 7
TRM 3.6.1 0
TRM 3.6.2 7
TRM 3.7.1 0
TRM 3.7.2 0
TRM 3.7.3 0
TRM 3.7.4 0
TRM 3.7.5 0
TRM 3.7.6 0
TRM 3.8.1 5
TRM 3.8.2 0
TRM 3.8.3 0
TRM 3.8.4 0
TRM 3.9.1 6
TRM 3.9.2 6
Technical Requirements Manual TABLE OF CONTENTS FSAR SCOPE VEGP Units 3 and 4 TRM - i Revision 7
- NOTE -
Refer to Updated FSAR Section 16.3 for discussion of the FSAR Scope.
TRM 1.0 USE AND APPLICATION TRM 1.1 Definitions.................................................................... DCD-Plant Specific (Tier 2)
TRM 1.2 Logical Connectors.......................................................................... Administrative TRM 1.3 Completion Times............................................................................ Administrative TRM 1.4 Frequency....................................................................................... Administrative TRM 2.0 Not used TRM 3.0 TECHNICAL REQUIREMENT (TR) APPLICABILITY TR 3.0.1
.................................................................................................... Administrative TR 3.0.2
.................................................................................................... Administrative TR 3.0.3
................................................................................ DCD-Plant Specific (Tier 2)
TRM 3.0 TECHNICAL REQUIREMENT SURVEILLANCE (TRS) APPLICABILITY TRS 3.0.1
.................................................................................................... Administrative TRS 3.0.2
.................................................................................................... Administrative TRS 3.0.3
.................................................................................................... Administrative TRM 3.1 Not used TRM 3.2 Not used TRM 3.3 INSTRUMENTATION TR 3.3.1 Diverse Actuation System (DAS)
Automatic Functions.............................................. DCD-Plant Specific (Tier 2)
TR 3.3.2 Feedwater Flow............................................................................... Administrative TRM 3.4 Not used TRM 3.5 Not used TRM 3.6 CONTAINMENT SYSTEMS TR 3.6.1 Passive Containment Cooling Water Storage Tank (PCCWST) and Spent Fuel Pool Makeup
- Long Term Shutdown........................................... DCD-Plant Specific (Tier 2)
TR 3.6.2 Hydrogen Igniters........................................................ DCD-Plant Specific (Tier 2)
Technical Requirements Manual TABLE OF CONTENTS FSAR SCOPE VEGP Units 3 and 4 TRM - ii Revision 7 TRM 3.7 PLANT SYSTEMS TR 3.7.1 Normal Residual Heat Removal System (RNS)
- Reactor Coolant System (RCS) Makeup............. DCD-Plant Specific (Tier 2)
TR 3.7.2 Normal Residual Heat Removal System (RNS)
- Reactor Coolant System (RCS) Open................ DCD-Plant Specific (Tier 2)
TR 3.7.3 Component Cooling Water System (CCS)
- Reactor Coolant System (RCS) Open................ DCD-Plant Specific (Tier 2)
TR 3.7.4 Service Water System (SWS)
- Reactor Coolant System (RCS) Open................ DCD-Plant Specific (Tier 2)
TR 3.7.5 Main Control Room (MCR) Cooling
- Long Term Shutdown........................................... DCD-Plant Specific (Tier 2)
TR 3.7.6 I&C Room Cooling - Long Term Shutdown.................. DCD-Plant Specific (Tier 2)
TRM 3.8 ELECTRICAL POWER SYSTEMS TR 3.8.1 AC Power Supplies - Operating.................................. DCD-Plant Specific (Tier 2)
- Reactor Coolant System (RCS) Open................ DCD-Plant Specific (Tier 2)
TR 3.8.3 AC Power Supplies - Long Term Shutdown................ DCD-Plant Specific (Tier 2)
TR 3.8.4 Non-Class 1E DC and UPS System (EDS)................. DCD-Plant Specific (Tier 2)
TRM 3.9 REFUELING OPERATIONS TR 3.9.1 Containment Penetrations............................................. UFSAR Standard Content TR 3.9.2 Containment Air Filtration System (VFS)....................... UFSAR Standard Content TRM 4.0 Not used TRM 5.0 Not used
Technical Requirements Manual Definitions TRM 1.1 VEGP Units 3 and 4 TRM 1.1 - 1 Revision 0 TRM 1.0 USE AND APPLICATION TRM 1.1 Definitions
- NOTE -
- 1.
Technical Requirements (TR) Definitions follow those terms defined in Technical Specifications (TS) Section 1.1. Only definitions specific to the TRM will be defined in this section.
- 2.
The defined terms appear in capitalized type and are applicable throughout the TRM.
- 3.
When a term is defined in both the TS and the TRM, the TRM definition takes precedence within the TRM.
- 4.
When a term defined in TS Section 1.1 refers to OPERABLE or OPERABILITY its use within the TRM is understood to apply the TRM requirement-specific defined terms (i.e.,
FUNCTIONAL or FUNCTIONALITY) as required in each Technical Requirement.
Term Definition ACTIONS ACTIONS shall be that part of a Technical Requirement that prescribes Required Actions to be taken under designated Conditions within specified Completion Times.
FUNCTIONAL -
FUNCTIONALITY A system, subsystem, train, component, or device shall be FUNCTIONAL or have FUNCTIONALITY when it is capable of performing its specified function(s), as set forth in the current licensing basis and when all necessary attendant instrumentation, controls, normal or emergency electrical power, cooling and seal water, lubrication, and other auxiliary equipment that are required for the system, subsystem, train, component, or device to perform its specified function(s) are also capable of performing their related support function(s).
Technical Requirements Manual Logical Connectors TRM 1.2 TRM 1.0 USE AND APPLICATION TRM 1.2 Logical Connectors VEGP Units 3 and 4 TRM 1.2 - 1 Revision 0 Logical Connectors are discussed in Technical Specification Section 1.2 and are applicable throughout the Technical Requirements Manual (TRM). When TS Section 1.2 refers to OPERABLE or OPERABILITY its use as applied to the TRM is understood to apply the TRM requirement-specific defined terms (i.e., FUNCTIONAL or FUNCTIONALITY) as required in each Technical Requirement.
Technical Requirements Manual Completion Times TRM 1.3 TRM 1.0 USE AND APPLICATION TRM 1.3 Completion Times VEGP Units 3 and 4 TRM 1.3 - 1 Revision 0 Completion Times are discussed in Technical Specification Section 1.3 and are applicable throughout the Technical Requirements Manual (TRM). When TS Section 1.3 refers to OPERABLE or OPERABILITY its use as applied to the TRM is understood to apply the TRM requirement-specific defined terms (i.e., FUNCTIONAL or FUNCTIONALITY) as required in each Technical Requirement. Similarly, when TS Section 1.3 refers to an LCO its use as applied to the TRM is understood to apply to Technical Requirements (TRs).
Technical Requirements Manual Frequency TRM 1.4 TRM 1.0 USE AND APPLICATION TRM 1.4 Frequency VEGP Units 3 and 4 TRM 1.4 - 1 Revision 0 Frequency is discussed in Technical Specification Section 1.4 and is applicable throughout the Technical Requirements Manual (TRM). When TS Section 1.4 refers to OPERABLE or OPERABILITY its use as applied to the TRM is understood to apply the TRM requirement-specific defined terms (i.e., FUNCTIONAL or FUNCTIONALITY) as required in each Technical Requirement. Similarly, when TS Section 1.4 refers to an LCO its use as applied to the TRM is understood to apply to Technical Requirements (TRs). TS Section 1.4 references to LCO 3.0.4 and SR 3.0.4 are not applicable to the TRM.
Technical Requirements Manual TR Applicability TRM 3.0 TRM 3.0 TECHNICAL REQUIREMENT (TR) APPLICABILITY VEGP Units 3 and 4 TRM 3.0 - 1 Revision 0 TR 3.0.1 Each TR shall be met during the MODES or other specified conditions in the Applicability, except as provided in TR 3.0.2.
TR 3.0.2 Upon discovery of a failure to meet a TR, the Required Actions of the associated Conditions shall be met.
If the TR is met or is no longer applicable prior to expiration of the specified Completion Time(s), completion of the Required Action(s) is not required, unless otherwise stated.
TR 3.0.3 When a TR is not met and the associated ACTIONS are not met, an associated ACTION is not provided, or if directed by the associated ACTIONS:
- a.
Initiate action to restore compliance with the TR or associated ACTIONS immediately;
- b.
Initiate action to assess and manage the risk of the resulting unit configuration immediately, and
- NOTE -
TR 3.0.3.c shall be completed if TR 3.0.3 is entered.
- c.
Enter the circumstances of entry into TR 3.0.3 into the Corrective Action Program within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Technical Requirements Manual TRS Applicability TRM 3.0 TRM 3.0 TECHNICAL REQUIREMENT SURVEILLANCE (TRS) APPLICABILITY VEGP Units 3 and 4 TRM 3.0 - 2 Revision 0 TRS 3.0.1 TRSs shall be met during the MODES or other specified conditions in the Applicability for the individual TR, unless otherwise stated in the TRS.
Failure to meet a TRS, whether such failure is experienced during the performance of the TRS or between performances of the TRS, shall be failure to meet the TR. Failure to perform a TRS within the specified Frequency shall be failure to meet the TR. TRSs do not have to be performed on nonfunctional equipment or variables outside specified limits.
TRS 3.0.2 The specified Frequency for each TRS is met if the TRS is performed within 1.25 times the interval specified in the Frequency, as measured from the previous performance or as measured from the time a specified condition of the Frequency is met.
For Frequencies specified as once, the above interval extension does not apply.
If a Completion Time requires periodic performance on a once per...
basis, the above Frequency extension applies to each performance after the initial performance.
Exceptions to this TRS are stated in the individual TRSs.
TRS 3.0.3 If it is discovered that a TRS was not performed within its specified Frequency, then compliance with the requirement to declare theTR not met may be delayed, from the time of discovery, up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or up to the limit of the specified Frequency, which ever is greater. This delay period is permitted to allow performance of the TRS. A risk evaluation shall be performed for any TRS delayed greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and the risk impact shall be managed.
If the TRS is not performed within the delay period, the TR must immediately be declared not met, and the applicable Condition(s) must be entered.
When the TRS is performed within the delay period, and the TRS is not met, the TR must immediately be declared not met, and the applicable Condition(s) must be entered.
Technical Requirements Manual DAS Automatic Actuation TRM 3.3.1 VEGP Units 3 and 4 TRM 3.3.1 - 1 Revision 3 TRM 3.3 INSTRUMENTATION TRM 3.3.1 Diverse Actuation System (DAS) Automatic Actuation TR 3.3.1 DAS automatic actuation functions and DAS automatic actuation initiation signals listed in Table TR 3.3.1-1 shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, 3, 4, and 5, MODE 6 with with upper internals in place, MODE 6 with cavity level < 23 feet above the top of the reactor vessel flange.
- NOTE -
DAS ATWS mitigation functions of reactor trip and turbine trip actuation are only required in MODE 1.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
One or more automatic actuation functions with one or more required channels not FUNCTIONAL.
A.1 Restore required channel(s) to FUNCTIONAL status.
14 days
Technical Requirements Manual DAS Automatic Actuation TRM 3.3.1 VEGP Units 3 and 4 TRM 3.3.1 - 2 Revision 3 TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.3.1.1 Perform CHANNEL CHECK on each required channel.
30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> TRS 3.3.1.2 Perform CHANNEL OPERATIONAL TEST (COT) on each required channel.
92 days TRS 3.3.1.3 Perform CHANNEL CALIBRATION on each required channel.
24 months TRS 3.3.1.4
- NOTE -
Only required to be met in MODE 1.
Verify rod drive MG set field control relays open on demand.
24 months
Technical Requirements Manual DAS Automatic Actuation TRM 3.3.1 VEGP Units 3 and 4 TRM 3.3.1 - 3 Revision 3 Table TR 3.3.1-1 (page 1 of 1)
DAS Automatic Actuation Initiation Signals INITIATION SIGNAL REQUIRED CHANNELS SETPOINT
> 27%
- 2. Hot Leg Temperature - High 1 per Hot Leg
< 650° F
- 3. Pressurizer Level - Low 2
> 7%
- 4. Containment Temperature - High 2
< 200° F
Technical Requirements Manual DAS Automatic Actuation TRM 3.3.1 VEGP Units 3 and 4 TRM 3.3.1 - 4 Revision 3 TRM 3.3.1 Diverse Actuation System (DAS) Automatic Actuation Bases The DAS automatic actuation functions include: (1) the DAS ATWS mitigation functions of reactor trip (i.e., MG set field control relay open), turbine trip, and passive residual heat removal heat exchanger (PRHR HX) actuation; and (2) the DAS Engineering Safeguards Features Actuation (ESFA) functions of PRHR HX actuation, CMT actuation, RCP trip, Passive Containment Cooling actuation, and selected containment isolation actuation.
The DAS ATWS mitigation function actuation provides ATWS mitigation capability on:
SG Wide Range Level - Low; and Hot Leg Temperature - High.
This function is important based on 10 CFR 50.62 (ATWS Rule) and because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to actuate.
The DAS ESFA functions provide accident mitigation capability on:
SG Wide Range Level - Low; Hot Leg Temperature - High; Pressurizer Level - Low; and Containment Temperature - High.
This function is important because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to actuate.
The DAS uses a 2-out-of-2 logic to actuate automatic functions. When a required channel is not FUNCTIONAL the automatic DAS function is not FUNCTIONAL. FSAR subsection 7.7.1.11 provides additional information.
Automated operator aids may be used to facilitate performance of the CHANNEL CHECK. An automated tester may be used to facilitate performance of the CHANNEL OPERATIONAL TEST.
The DAS ATWS mitigation function is required during MODE 1 when ATWS is a limiting event.
The DAS ESFA mitigation functions are required during MODES 1, 2, 3, 4, 5, and 6 when accident mitigation is beneficial to the PRA results. The DAS ESFA is required in MODE 6 with upper internals in place or reactor cavity level < 23 feet above the top of the reactor vessel flange. Planned maintenance affecting these DAS functions should be performed in MODE 6 when the refueling cavity is 23 ft; this MODE is selected because requiring DAS ESFA is not anticipated in this MODE.
Technical Requirements Manual Feedwater Flow TRM 3.3.2 VEGP Units 3 and 4 TRM 3.3.2 - 1 Revision 7 TRM 3.3 INSTRUMENTATION TRM 3.3.2 Feedwater Flow TR 3.3.2 Caldon/Cameron Leading Edge Flow Meter (LEFM) CheckPlus system feedwater flow calorimetric input shall be FUNCTIONAL.
APPLICABILITY:
MODE 1 with THERMAL POWER > 3366 MWt.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
LEFM CheckPlus system not FUNCTIONAL.
A.1 Initiate action to verify calorimetric power is utilizing feedwater flow input from venturi elements.
Immediately AND A.2 Restore LEFM CheckPlus system to FUNCTIONAL status.
48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> B.
Required action and associated Completion Time not met.
B.1 Initiate action to reduce THERMAL POWER to 3366 MWt.
Immediately TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.3.2.1 Perform CHANNEL CHECK on LEFM CheckPlus system feedwater flow calorimetric input.
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> TRS 3.3.2.2 Perform CHANNEL CALIBRATION and preventative maintenance in accordance with LEFM CheckPlus system technical manuals and recommendations.
Per technical manuals and recommendations
Technical Requirements Manual Feedwater Flow TRM 3.3.2 VEGP Units 3 and 4 TRM 3.3.2 - 2 Revision 7 TRM 3.3.2 Feedwater Flow Bases The plant operating instrumentation selected for feedwater flow measurement is a Caldon
[Cameron] LEFM CheckPlus System. This selected plant operating instrumentation has documented instrumentation uncertainties to calculate a power calorimetric uncertainty that confirms the 1% uncertainty assumed for the initial reactor power in the safety analysis bounds the calculated calorimetric power uncertainty values. While the main feedwater flow measurement supports a 1% RTP uncertainty, the safety analysis uses a conservative 2% RTP uncertainty (i.e., initial power of 102% [3468 MWt]).
To determine volumetric flow rate, the Cameron/Caldon ultrasonic flow meter instrumentation transmits an acoustic pulse along eight selected paths and records the arrival of the pulse at the receiver. Another eight pulses are transmitted in the opposite direction and the time for those pulses is also recorded. Since the speed of an acoustic pulse will increase in the direction of flow and will decrease when transmitted against the flow, the difference in the upstream and downstream transit times for the acoustic pulse provides information on flow velocity. Once the difference in travel times is determined, the average velocity of the fluid along the acoustic path can be determined. Therefore, the difference in transit time is proportional to the average velocity of the fluid along the acoustic path.
Operation at indicated core power levels at 3400 MWt (i.e., RATED THERMAL POWER) requires a calorimetric power uncertainty determination of less than 2.0%. This is only possible if the LEFM CheckPlus System feedwater flow instrumentation is available as the input to the calorimetric is FUNCTIONAL. The LEFM system measures and transmits data with lower uncertainty than the instrumentation from the feedwater flow venturi. The feedwater flow venturi input to the calorimetric will support operation above 3366 MWt for up to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> while the LEFM system is not FUNCTIONAL. Upon the expiration of the 48-hour Completion Time, reactor core power is reduced to 3366 MWt.
Technical Requirements Manual PCCWST and Spent Fuel Pool Makeup
- Long Term Shutdown TRM 3.6.1 VEGP Units 3 and 4 TRM 3.6.1 - 1 Revision 0 TRM 3.6 CONTAINMENT SYSTEMS TRM 3.6.1 Passive Containment Cooling Water Storage Tank (PCCWST) and Spent Fuel Pool Makeup - Long Term Shutdown TR 3.6.1 Long term makeup to the PCCWST and the Spent Fuel Pool shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, 3, 4, 5, and 6.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
Passive containment cooling ancillary water storage tank (PCCAWST) volume 780,000 gal.
A.1 Restore PCCAWST volume to > 780,000 gal.
14 days B.
Required Passive Containment Cooling System (PCS) recirculation pump not FUNCTIONAL.
B.1 Restore required PCS recirculation pump to FUNCTIONAL status.
14 days
Technical Requirements Manual PCCWST and Spent Fuel Pool Makeup
- Long Term Shutdown TRM 3.6.1 VEGP Units 3 and 4 TRM 3.6.1 - 2 Revision 0 TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.6.1.1 Verify water volume in the PCCAWST is
> 780,000 gal.
31 days TRS 3.6.1.2 Verify required PCS recirculation pump provides recirculation of the PCCWST at > 100 gpm.
92 days TRS 3.6.1.3 Verify required PCS recirculation pump transfers
> 100 gpm from the PCCAWST to the PCCWST.
During this test, required PCS recirculation pump shall be powered from an ancillary diesel.
10 years
Technical Requirements Manual PCCWST and Spent Fuel Pool Makeup
- Long Term Shutdown TRM 3.6.1 VEGP Units 3 and 4 TRM 3.6.1 - 3 Revision 0 TRM 3.6.1 Passive Containment Cooling Water Storage Tank (PCCWST) and Spent Fuel Pool Makeup - Long Term Shutdown BASES The PCS recirculation pumps provide long-term shutdown support by transferring water from the PCCAWST to the PCCWST and the spent fuel pool. The specified PCCAWST volume is sufficient to maintain PCS and Spent Fuel Pool cooling during the 3 to 7 day time period following an accident. After 7 days, water brought in from offsite allows the PCCWST to continue to provide PCS cooling and makeup to the spent fuel pool. This PCCWST makeup function is important because it supports long-term shutdown operation. A minimum availability of 90% is assumed for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The PCCWST makeup function involves the use of one PCS recirculation pump, the PCCAWST and the line connecting the PCCAWST with the PCCWST and spent fuel pool. One PCS recirculation pump normally operates to recirculate the PCCWST. FSAR subsections 6.2.2 and 9.1.3 contain additional information on the PCCWST and spent fuel pool makeup function.
The PCCWST makeup function is required during MODES of operation when PCS and spent fuel pool cooling is required; one PCS recirculation pump and PCCAWST are required during all MODES.
Planned maintenance should be performed on the redundant pump (i.e., the pump not required to be FUNCTIONAL). Planned maintenance affecting the PCCAWST that requires less than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to perform can be performed in any MODE of operation. Planned maintenance requiring more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> should be performed in MODE 5 or 6 when the calculated core decay heat is 6.0 MWt. The basis for this recommendation is that the long-term PCS makeup is not required in this condition, and in most cases, the PCCWST can provide the required makeup to the spent fuel pool.
Technical Requirements Manual Hydrogen Igniters TRM 3.6.2 VEGP Units 3 and 4 TRM 3.6.2 - 1 Revision 7 TRM 3.6 CONTAINMENT SYSTEMS TRM 3.6.2 Hydrogen Igniters TR 3.6.2 Hydrogen igniters shall be FUNCTIONAL in accordance with Table TR 3.6.2-1.
APPLICABILITY:
MODES 1 and 2, MODE 5 with RCS pressure boundary open, MODE 6 with with upper internals in place, MODE 6 with cavity level < 23 feet above the top of the reactor vessel flange.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
One or more required hydrogen igniters not FUNCTIONAL.
A.1 Restore required igniters to FUNCTIONAL status.
14 days TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.6.2.1 Energize each required hydrogen igniter and verify the surface temperature is 1700°F.
Each refueling outage
Technical Requirements Manual Hydrogen Igniters TRM 3.6.2 VEGP Units 3 and 4 TRM 3.6.2 - 2 Revision 7 Table TR 3.6.2-1 (page 1 of 1)
Hydrogen Igniters LOCATION REQUIRED IGNITERS
- 1.
Loop Compartment 01 3
- 2.
Loop Compartment 02 3
- 3.
Pressurizer Compartment 3
- 4.
Tunnel connecting Loop Compartments 5
- 5.
Southeast Valve Room &
Southeast Accumulator Room 2
- 6.
East Valve Room, Northeast Accumulator Room, & Northeast Valve Room 2(1)
- 7.
North CVS Equipment Room 2
- 8.
Lower Compartment Area (CMT and Valve Area) 10
- 9.
IRWST 5
- 10.
IRWST Inlet 2
- 11.
IRWST Roof Vents 2
- 12.
Refueling Cavity 3
- 13.
Upper Compartment - Lower Region 9
- 14.
Upper Compartment - Mid Region 3
- 15.
Upper Compartment - Upper Region 3
NOTE:
(1) Igniter 18 and either Igniter 17 or Igniter 19.
Technical Requirements Manual Hydrogen Igniters TRM 3.6.2 VEGP Units 3 and 4 TRM 3.6.2 - 3 Revision 7 TRM 3.6.2 Hydrogen Igniters Bases The hydrogen igniters are required to provide the capability of burning hydrogen generated during severe accidents in order to prevent failure of the containment due to hydrogen detonation. These hydrogen igniters are required by 10 CFR 50.34 to limit the buildup of hydrogen to less than 10% assuming that 100% of the active zircaloy fuel cladding is oxidized.
This function is also important because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The igniters are distributed in the containment to limit the buildup of hydrogen in local areas.
Two groups of igniters are provided in each area; one of which is sufficient to limit the buildup of hydrogen. When an igniter is energized, the igniter surface heats up to 1700°F. This temperature is sufficient to ignite hydrogen in the vicinity of the igniter when the lower flammability limit is reached. FSAR subsection 6.2.4 provides additional information.
The hydrogen igniter function is required during MODES 1 and 2 when core decay heat is high and during MODE 5 when the RCS pressure boundary is open and in MODE 6 with cavity level
< 23 feet above the top of the reactor vessel flange. Planned maintenance should be performed on hydrogen igniters when they are not required to meet this availability control. Table TR 3.6.2-1 indicates the minimum number of hydrogen igniters that are required.
Technical Requirements Manual RNS - RCS Makeup TRM 3.7.1 VEGP Units 3 and 4 TRM 3.7.1 - 1 Revision 0 TRM 3.7 PLANT SYSTEMS TRM 3.7.1 Normal Residual Heat Removal System (RNS) - Reactor Coolant System (RCS)
Makeup TR 3.7.1 One train of RNS - RCS makeup shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, and 3.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
Required RNS - RCS makeup train not FUNCTIONAL.
A.1 Restore required RNS -
RCS makeup train to FUNCTIONAL status.
14 days TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.7.1.1 Verify required RNS pump develops a differential head of 330 feet on recirculation flow.
92 days TRS 3.7.1.2 Verify the following valves stroke open:
RNS V011, RNS Discharge Containment Isolation RNS V022, RNS Suction Header Containment Isolation RNS V023, RNS Suction from IRWST Isolation RNS V055, RNS Suction from Cask Loading Pit 92 days
Technical Requirements Manual RNS - RCS Makeup TRM 3.7.1 VEGP Units 3 and 4 TRM 3.7.1 - 2 Revision 0 TRM 3.7.1 Normal Residual Heat Removal System (RNS) - Reactor Coolant System (RCS)
Makeup Bases The RNS - RCS makeup function provides a nonsafety-related means of injecting IRWST water into the RCS following ADS actuations. The RNS - RCS makeup function is important because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to operate.
One train of RNS - RCS makeup includes one RNS pump and the line from the cask loading pit (CLP) to the RCS. One valve in the line between the CLP and the RCS is normally closed and needs to be opened to allow injection. Later on, the RNS suction is switched from the CLP to the IRWST. Two valves in the IRWST line are normally closed and must be opened to allow recirculation. This equipment does not normally operate during MODES 1, 2, and 3. FSAR subsection 5.4.7 contains additional information on the RNS.
The RNS - RCS makeup function is required during MODES 1, 2, and 3 because decay heat is higher and the need for ADS is greater.
Planned maintenance on redundant RNS SSCs should be performed during MODE 1, 2, or 3.
Such maintenance should be performed on an RNS SSC not required to be FUNCTIONAL.
The basis for this recommendation is that the RNS is more risk important during shutdown MODES when it is normally operating than during other MODES when it only provides a backup to PXS injection.
Planned maintenance on non-redundant RNS valves (such as V011, V022, V023, V055) should be performed to minimize the impact on their RNS - RCS makeup and their containment isolation capability. Non-pressure boundary maintenance should be performed during MODE 5 with a visible pressurizer level or MODE 6 with cavity level 23 feet above the top of the reactor vessel flange. In these MODES, these valves need to be open but they do not need to be able to close. Containment closure which is required in these MODES can be satisfied by one normally open operable valve. Pressure boundary maintenance can not be performed during MODES when the RNS is used to cool the core, therefore such maintenance should be performed during MODE 1, 2, or 3. Since these valves are also containment isolation valves, maintenance that renders the valves inoperable requires that the containment isolation valve located in series with the inoperable valve has to be closed and de-activated. The basis for this recommendation is that the RNS is more risk important during shutdown MODES when it is normally operating than during other MODES when it only provides a backup to PXS injection.
In addition, it is not possible to perform pressure boundary maintenance of these valves during RNS operation.
Technical Requirements Manual RNS - RCS Open TRM 3.7.2 VEGP Units 3 and 4 TRM 3.7.2 - 1 Revision 0 TRM 3.7 PLANT SYSTEMS TRM 3.7.2 Normal Residual Heat Removal System (RNS) - Reactor Coolant System (RCS)
Open TR 3.7.2 Two trains of RNS RCS shutdown heat removal shall be FUNCTIONAL and one RNS pump in operation.
APPLICABILITY:
MODE 5 with RCS pressure boundary open, MODE 6 with with upper internals in place, MODE 6 with cavity level < 23 feet above the top of the reactor vessel flange.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
One RNS RCS shutdown heat removal train not FUNCTIONAL.
A.1 Initiate actions to increase the water inventory above the core.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR AND Required RNS pump not in operation.
A.2 Restore two trains of RNS RCS shutdown heat removal to FUNCTIONAL status and one RNS pump in operation.
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />
Technical Requirements Manual RNS - RCS Open TRM 3.7.2 VEGP Units 3 and 4 TRM 3.7.2 - 2 Revision 0 TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.7.2.1 Verify one RNS pump is in operation and that the required RNS pump circulates reactor coolant at a flow > 1580 gpm.
OR Verify both RNS pumps are in operation and circulating reactor coolant at a flow > 2000 gpm.
Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to entering the Applicability
Technical Requirements Manual RNS - RCS Open TRM 3.7.2 VEGP Units 3 and 4 TRM 3.7.2 - 3 Revision 0 TRM 3.7.2 Normal Residual Heat Removal System (RNS) - Reactor Coolant System (RCS)
Open Bases The RNS cooling function provides a nonsafety-related means to normally cool the RCS during shutdown operations (MODES 4, 5, and 6). This RNS cooling function is important during conditions when the RCS pressure boundary is open and the refueling cavity is not flooded because it reduces the probability of an initiating event due to loss of RNS cooling and because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The RCS is considered open when its pressure boundary is not intact. The RCS is also considered open if there is no visible level in the pressurizer. The margin provided in the PRA study assumes a minimum availability of 90%
for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The RNS cooling of the RCS involves the RNS suction line from the RCS HL, the two RNS pumps and the RNS discharge line returning to the RCS through the DVI lines. The valves located in these lines should be open prior to the plant entering reduced inventory conditions.
One of the RNS pumps has to be operating; the other pump may be operating or may be in standby. Standby includes the capability of being able to be placed into operation from the main control room. FSAR subsection 5.4.7 contains additional information on the RNS.
Both RNS pumps are required during the Applicability when the loss of RNS cooling is risk important. If both RNS pumps are not FUNCTIONAL, the plant should not enter these conditions. If the plant has entered reduced inventory conditions, then the plant should take action to restore full system operation or leave the Applicability. If the plant has not restored full system operation or left the Applicability within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, then actions need to be initiated to increase the RCS water level to either 20% pressurizer level or to a refueling cavity 23 ft.
Planned maintenance affecting this RNS cooling function should be performed in MODE 1, 2, or 3 when the RNS is not normally operating. The basis for this recommendation is that the RNS is more risk important during shutdown MODES, especially during the Applicability conditions than during other MODES when it only provides a backup to PXS injection.
Technical Requirements Manual CCS - RCS Open TRM 3.7.3 VEGP Units 3 and 4 TRM 3.7.3 - 1 Revision 0 TRM 3.7 PLANT SYSTEMS TRM 3.7.3 Component Cooling Water System (CCS) - Reactor Coolant System (RCS)
Open TR 3.7.3 Two CCS trains shall be FUNCTIONAL and one CCS pump in operation to support the operating Normal Residual Heat Removal System (RNS)
RCS shutdown heat removal train.
APPLICABILITY:
MODE 5 with RCS pressure boundary open, MODE 6 with with upper internals in place, MODE 6 with cavity level < 23 feet above the top of the reactor vessel flange.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
One CCS train not FUNCTIONAL.
A.1 Initiate actions to increase the water inventory above the core.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR AND Required CCS pump not in operation to support operating RNS RCS shutdown heat removal train.
A.2 Restore two CCS trains to FUNCTIONAL status and one CCS pump in operation to support operating RNS RCS shutdown heat removal train.
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />
Technical Requirements Manual CCS - RCS Open TRM 3.7.3 VEGP Units 3 and 4 TRM 3.7.3 - 2 Revision 0 TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.7.3.1 Verify one CCS pump is in operation and each CCS pump operating individually can provide a CCS flow through one RNS heat exchanger > 2685 gpm.
OR Verify both CCS pumps are in operation with CCS flow through each RNS heat exchanger > 2685 gpm.
Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to entering the Applicability
Technical Requirements Manual CCS - RCS Open TRM 3.7.3 VEGP Units 3 and 4 TRM 3.7.3 - 3 Revision 0 TRM 3.7.3 Component Cooling Water System (CCS) - Reactor Coolant System (RCS)
Open Bases The CCS cooling of the RNS HXs provides a nonsafety-related means to normally cool the RCS during shutdown operations (MODES 4, 5, and 6). This RNS cooling function is important because it reduces the probability of an initiating event due to loss of RNS cooling and because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The RCS is considered open when its pressure boundary is not intact. The RCS is also considered open if there is no visible level in the pressurizer. The margin provided in the PRA study assumes a minimum availability of 90%
for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The CCS cooling of the RNS involves two CCS pumps and HXs and the CCS line to the RNS HXs. The valves around the CCS pumps and HXs and in the lines to the RNS HXs should be open prior to the plant entering these conditions. One of the CCS pumps and its HX has to be operating. One of the lines to a RNS HX also has to be open. The other CCS pump and HX may be operating or may be in standby. Standby includes the capability of being able to be placed into operation from the main control room. FSAR subsection 9.2.2 contains additional information on the CCS.
Both CCS pumps are required during the Applicability when the loss of RNS cooling is risk important. If both CCS pumps are not FUNCTIONAL, the plant should not enter these conditions. If the plant has entered these conditions, then the plant should take action to restore both CCS pumps or to leave these conditions. If the plant has not restored full system operation or left the Applicability within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, then actions need to be initiated to increase the RCS water level to either 20% pressurizer level or to a refueling cavity 23 ft.
Planned maintenance affecting this CCS cooling function should be performed in MODE 1, 2, or 3 when the CCS is not supporting RNS operation. The basis for this recommendation is that the CCS is more risk important during shutdown MODES, especially during the Applicability conditions than during other MODES.
Technical Requirements Manual SWS - RCS Open TRM 3.7.4 VEGP Units 3 and 4 TRM 3.7.4 - 1 Revision 0 TRM 3.7 PLANT SYSTEMS TRM 3.7.4 Service Water System (SWS) - Reactor Coolant System (RCS) Open TR 3.7.4 Two SWS trains shall be FUNCTIONAL and one SWS pump in operation to support Component Cooling Water System (CCS) cooling.
APPLICABILITY:
MODE 5 with RCS pressure boundary open, MODE 6 with with upper internals in place, MODE 6 with cavity level < 23 feet above the top of the reactor vessel flange.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
One SWS train not FUNCTIONAL.
A.1 Initiate actions to increase the water inventory above the core.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR AND Required SWS pump not in operation to support CCS cooling.
A.2 Restore two SWS trains to FUNCTIONAL status and one SWS pump in operation to support CCS cooling.
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.7.4.1 Verify one SWS pump is in operation and each SWS pump operating individually can provide a SWS flow
> 10,000 gpm.
Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to entering the Applicability TRS 3.7.4.2 Operate each cooling tower fan for > 15 min.
Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to entering the Applicability
Technical Requirements Manual SWS - RCS Open TRM 3.7.4 VEGP Units 3 and 4 TRM 3.7.4 - 2 Revision 0 TRM 3.7.4 Service Water System (SWS) - Reactor Coolant System (RCS) Open Bases The SWS cooling of the CCS HXs provides a nonsafety-related means to normally cool the RNS HX which cools the RCS during shutdown operations (MODES 4, 5, and 6). This RNS cooling function is important because it reduces the probability of an initiating event due to loss of RNS cooling and because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The RCS is considered open when its pressure boundary is not intact. The RCS is also considered open if there is no visible level in the pressurizer. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The SWS cooling of the CCS HXs involves two SWS pumps and cooling tower fans and the SWS line to the CCS HXs. The valves in the SWS lines should be open prior to the plant entering these conditions. One of the SWS pumps and its cooling tower fan has to be operating. The other SWS pump and cooling tower fan may be operating or may be in standby.
Standby includes the capability of being able to be placed into operation from the main control room. FSAR subsection 9.2.1 contains additional information on the SWS.
Both SWS pumps and cooling tower fans are required during the Applicability when the loss of RNS cooling is risk important. If both SWS pumps and cooling tower fans are not FUNCTIONAL, the plant should not enter these conditions. If the plant has entered these conditions, then the plant should take action to restore both SWS pumps / fans or to leave these conditions. If the plant has not restored full system operation or left the Applicability within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, then actions need to be initiated to increase the RCS water level to either 20%
pressurizer level or to a refueling cavity 23 ft.
Planned maintenance affecting this SWS cooling function should be performed in MODES when the SWS is not supporting RNS operation, i.e., during MODE 1, 2, or 3. The basis for this recommendation is that the SWS is more risk important during shutdown MODES, especially during the Applicability conditions than during other MODES.
Technical Requirements Manual MCR Cooling
- Long Term Shutdown TRM 3.7.5 VEGP Units 3 and 4 TRM 3.7.5 - 1 Revision 0 TRM 3.7 PLANT SYSTEMS TRM 3.7.5 Main Control Room (MCR) Cooling - Long Term Shutdown TR 3.7.5 Long term cooling of the MCR shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, 3, 4, 5, and 6.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
Required MCR ancillary fan not FUNCTIONAL.
A.1 Restore required MCR ancillary fan to FUNCTIONAL status.
14 days TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.7.5.1 Operate required MCR ancillary fan for > 15 min.
92 days TRS 3.7.5.2 Verify required MCR ancillary fan can provide a flow of air into the MCR for > 15 min. During this test, the required MCR ancillary fan will be powered from an ancillary diesel.
10 years
Technical Requirements Manual MCR Cooling
- Long Term Shutdown TRM 3.7.5 VEGP Units 3 and 4 TRM 3.7.5 - 2 Revision 0 TRM 3.7.5 Main Control Room (MCR) Cooling - Long Term Shutdown Bases The MCR ancillary fans provide long term shutdown support by cooling the main control room.
For the first three days after an accident the emergency HVAC system (VES) together with the passive heat sinks in the MCR provide cooling of the MCR. After 3 days, the MCR ancillary fans can be used to circulate ambient air through the MCR to provide cooling. The long term MCR cooling function is required during all MODES of operation. This long term MCR cooling function is important because it supports long-term shutdown operation. A minimum availability of 90% is assumed for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The long term MCR cooling function involves the use of a MCR ancillary fan. During TRS 3.7.5.1 the required fan will be run to verify that it operates without providing flow to the MCR. During TRS 3.7.5.2 the required fan will be connected to the MCR and operated such that it provides flow to the MCR. FSAR subsection 9.4.1 contains additional information on the long term MCR cooling function.
One MCR ancillary fan is required during all MODES of plant operation. Planned maintenance should not be performed on the required MCR ancillary fan during a required MODE of operation; planned maintenance should be performed on the redundant MCR ancillary fan (i.e.,
the fan not required to be FUNCTIONAL) during MODE 3 or 4, MODE 5 with a visible pressurizer level, or MODE 6 with the refueling cavity 23 ft; these MODES are selected because the reactor is tripped in these MODES and the risk of core damage is low.
Technical Requirements Manual I&C Room Cooling
- Long Term Shutdown TRM 3.7.6 VEGP Units 3 and 4 TRM 3.7.6 - 1 Revision 0 TRM 3.7 PLANT SYSTEMS TRM 3.7.6 I&C Room Cooling - Long Term Shutdown TR 3.7.6 Long term cooling of I&C rooms B & C shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, 3, 4, 5, and 6.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
One I&C room ancillary fan not FUNCTIONAL.
A.1 Restore I&C room ancillary fan to FUNCTIONAL status.
14 days TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.7.6.1 Operate each I&C room ancillary fan for > 15 min.
92 days TRS 3.7.6.2 Verify each I&C room ancillary fan can provide a flow of air into an I&C room for > 15 min. During this test, the I&C room ancillary fans will be powered from an ancillary diesel.
10 years
Technical Requirements Manual I&C Room Cooling
- Long Term Shutdown TRM 3.7.6 VEGP Units 3 and 4 TRM 3.7.6 - 2 Revision 0 TRM 3.7.6 I&C Room Cooling - Long Term Shutdown Bases The I&C room ancillary fans provide long term shutdown support by cooling I&C rooms B & C which contain post accident instrument processing equipment. For the first three days after an accident the passive heat sinks in the I&C rooms provide cooling. After 3 days, the I&C room ancillary fans can be used to circulate ambient air through the I&C room to provide cooling. The long term I&C room cooling function is required during all MODES of operation. This long term I&C room cooling function is important because it supports long-term shutdown operation. A minimum availability of 90% is assumed for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The long term I&C room cooling function involves the use of two I&C room ancillary fans; each fan is associated with one I&C room (B or C). During TRS 3.7.6.1 each fan will be run to verify that it operates without providing flow to the I&C room. During TRS 3.7.6.2 each fan will be connected to its associated I&C room and operated such that flow is provided to the I&C room.
FSAR subsection 9.4.1 contains additional information on the long term I&C room cooling function.
Both I&C room ancillary fans are required during all MODES of plant operation.
Technical Requirements Manual AC Power Supplies
- Operating TRM 3.8.1 VEGP Units 3 and 4 TRM 3.8.1 - 1 Revision 5 TRM 3.8 ELECTRICAL POWER SYSTEMS TRM 3.8.1 AC Power Supplies - Operating TR 3.8.1 One standby diesel generator shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, 3, 4, and 5.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
Fuel volume in required standby diesel fuel tank 55,000 gal.
A.1 Restore fuel volume in required standby diesel fuel tank to > 55,000 gal.
14 days B.
Required fuel transfer pump or standby diesel generator not FUNCTIONAL.
B.1 Restore required fuel transfer pump and diesel generator to FUNCTIONAL status.
14 days
Technical Requirements Manual AC Power Supplies
- Operating TRM 3.8.1 VEGP Units 3 and 4 TRM 3.8.1 - 2 Revision 5 TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.8.1.1 Verify fuel oil volume in required standby diesel generator fuel tank is > 55,000 gal.
31 days TRS 3.8.1.2 Verify required fuel oil transfer pump provides a recirculation flow of > 8 gpm.
92 days TRS 3.8.1.3 Verify required standby diesel generator starts and operates at > 4000 kw for > 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. This test may utilize diesel engine prelube prior to starting and a warmup period prior to loading.
92 days TRS 3.8.1.4 Verify the required standby diesel generator starts and operates at > 4000 kw for > 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This test may utilize diesel engine prelube prior to starting and a warmup period prior to loading. Both diesel generators shall be operated at the same time during this test.
10 years
Technical Requirements Manual AC Power Supplies
- Operating TRM 3.8.1 VEGP Units 3 and 4 TRM 3.8.1 - 3 Revision 5 TRM 3.8.1 AC Power Supplies - Operating Bases AC power is required to power the RNS and to provide a nonsafety-related means of supplying power to the safety-related PMS for actuation and post accident monitoring. The RNS provides a nonsafety-related means to inject water into the RCS following ADS actuations in MODES 1, 2, 3, and 4 (when steam generators cool the RCS). This AC power supply function is important because it adds margin to the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to operate.
Two standby diesel generators are provided. Each standby diesel generator has its own fuel oil transfer pump and fuel oil tank. The volume of fuel oil required is that volume that is above the connection to the fuel oil transfer pump. FSAR subsection 8.3.1 contains additional information.
This AC power supply function is required during MODES 1, 2, 3, 4, and 5 when RNS injection and PMS actuation are more risk important. Planned maintenance should not be performed on required AC power supply SSCs during a required MODE of operation; planned maintenance should be performed on redundant AC power supply SSCs during MODE 1, 2, or 3 when the RNS is not normally in operation. The basis for this recommendation is that the AC power is more risk important during shutdown MODES, especially when the RCS is open as defined in TRM 3.7.2 Bases, than during other MODES.
Technical Requirements Manual AC Power Supplies
- RCS Open TRM 3.8.2 VEGP Units 3 and 4 TRM 3.8.2 - 1 Revision 0 TRM 3.8 ELECTRICAL POWER SYSTEMS TRM 3.8.2 AC Power Supplies - Reactor Coolant System (RCS) Open TR 3.8.2 The following AC power supplies shall be FUNCTIONAL to support Normal Residual Heat Removal System (RNS) operation:
- a.
One offsite circuit; and
- b.
One standby diesel generator.
APPLICABILITY:
MODE 5 with RCS pressure boundary open, MODE 6 with with upper internals in place, MODE 6 with cavity level < 23 feet above the top of the reactor vessel flange.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
One required AC power supply not FUNCTIONAL.
A.1 Initiate actions to increase the water inventory above the core.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> AND A.2 Restore required AC power supply to FUNCTIONAL status.
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.8.2.1 Verify required AC power supplies are FUNCTIONAL.
Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to entering the Applicability
Technical Requirements Manual AC Power Supplies
- RCS Open TRM 3.8.2 VEGP Units 3 and 4 TRM 3.8.2 - 2 Revision 0 TRM 3.8.2 AC Power Supplies - Reactor Coolant System (RCS) Open Bases AC power is required to power the RNS and its required support systems (CCS & SWS); the RNS provides a nonsafety-related means to normally cool the RCS during shutdown operations.
This RNS cooling function is important when the RCS pressure boundary is open and the refueling cavity is not flooded because it reduces the probability of an initiating event due to loss of RNS cooling during these conditions and because it provides margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The RCS is considered open when its pressure boundary is not intact. The RCS is also considered open if there is no visible level in the pressurizer. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to operate.
Two AC power supplies, one offsite and one onsite supply, are required as follows:
a) Offsite power through the transmission switchyard and either the main step-up transformer / unit auxiliary transformer or the reserve auxiliary transformer supply from the transmission switchyard, and b) Onsite power from one of the two standby diesel generators.
FSAR subsection 8.3.1 contains additional information on the standby diesel generators. FSAR Section 8.2 contains information on the offsite AC power supply.
One offsite and one onsite AC power supply are required during the Applicability when the loss of RNS cooling is important. If both of these AC power supplies are not FUNCTIONAL, the plant should not enter these conditions. If the plant has already entered these conditions, then the plant should take action to restore this AC power supply function or to leave these conditions. If the plant has not restored full system operation or left the Applicability within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, then actions need to be initiated to increase the RCS water level to either 20%
pressurizer level or to a refueling cavity 23 ft.
Planned maintenance should not be performed on required AC power supply SSCs. Planned maintenance affecting the standby diesel generators should be performed in MODE 1, 2, or 3 when the RNS is not normally in operation. Planned maintenance of the other AC power supply should be performed in MODE 2, 3, or 6 with the refueling cavity 23 ft. The basis for this recommendation is that the AC power is more risk important during shutdown MODES, especially during the Applicability conditions than during other MODES.
Technical Requirements Manual AC Power Supplies
- Long Term Shutdown TRM 3.8.3 VEGP Units 3 and 4 TRM 3.8.3 - 1 Revision 0 TRM 3.8 ELECTRICAL POWER SYSTEMS TRM 3.8.3 AC Power Supplies - Long Term Shutdown TR 3.8.3 One ancillary diesel generator shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, 3, 4, 5, and 6.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
Fuel volume in ancillary diesel fuel tank 600 gal.
A.1 Restore fuel volume in ancillary diesel fuel tank
> 600 gal.
14 days B.
Required ancillary diesel generator not FUNCTIONAL.
B.1 Restore required ancillary diesel generator to FUNCTIONAL status.
14 days
Technical Requirements Manual AC Power Supplies
- Long Term Shutdown TRM 3.8.3 VEGP Units 3 and 4 TRM 3.8.3 - 2 Revision 0 TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.8.3.1 Verify fuel volume in ancillary fuel tank is > 600 gal.
31 days TRS 3.8.3.2 Verify required ancillary diesel generator starts and operates for > 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> connected to a test load
> 35 kw. This test may utilize diesel engine warmup period prior to loading 92 days TRS 3.8.3.3 Verify required ancillary diesel generator starts and operates for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> while providing power to the regulating transformer, an ancillary control room fan, an ancillary I&C room fan and a passive containment cooling water storage tank recirculation pump that it will power in a long term post accident condition. Test loads will be applied to the output of the regulating transformers that represent the loads required for post-accident monitoring and control room lighting.
This test may utilize diesel engine warmup prior to loading. Both diesel generators will be operated at the same time during this test.
10 years
Technical Requirements Manual AC Power Supplies
- Long Term Shutdown TRM 3.8.3 VEGP Units 3 and 4 TRM 3.8.3 - 3 Revision 0 TRM 3.8.3 AC Power Supplies - Long Term Shutdown Bases The ancillary diesel generators provide long term power supplies for post accident monitoring, MCR and I&C room cooling, PCS and spent fuel water makeup. For the first 3 days after an accident, the 1E batteries provide power for post accident monitoring. Passive heat sinks provide cooling of the MCR and the I&C rooms. The initial water supply in the PCCWST provides for at least 3 days of PCS cooling. The initial water volume in the spent fuel pool normally provides for 7 days of spent fuel cooling; in some shutdown events the PCCWST is used to supplement the spent fuel pool. A minimum availability of 90% is assumed for this function during the Applicability, considering both maintenance unavailability and failures to operate.
After 3 days, ancillary diesel generators can be used to power the MCR and I&C room ancillary fans, the PCS recirculation pumps, and MCR lighting. In this time frame, the PCCWST provides water makeup to both the PCS and the spent fuel pool. An ancillary generator is required during all MODES of operation. This long term AC power supply function is important because it supports long-term shutdown operation.
The long-term AC power supply function involves the use of two ancillary diesel generators and an ancillary diesel generator fuel oil storage tank. The specified ancillary fuel oil storage tank volume is based on operation of both ancillary diesel-generators for 4 days. FSAR subsection 8.3.1 contains additional information on the long-term AC power supply function.
One ancillary diesel generator and the ancillary diesel generator fuel oil storage tank are required during all MODES of plant operation. Planned maintenance should not be performed on the required ancillary diesel generator during a required MODE of operation; planned maintenance should be performed on the redundant ancillary diesel generator. Planned maintenance affecting the ancillary diesel fuel tank that requires less than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to perform can be performed in any MODE of operation. Planned maintenance requiring more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> should be performed in MODE 6 with the refueling cavity 23 ft. The basis for this recommendation is that core decay heat is low and the risk of core damage is low in these MODES, the inventory of the refueling cavity results in slow response of the plant to accidents.
Technical Requirements Manual EDS TRM 3.8.4 VEGP Units 3 and 4 TRM 3.8.4 - 1 Revision 0 TRM 3.8 ELECTRICAL POWER SYSTEMS TRM 3.8.4 Non Class 1E DC and UPS System (EDS)
TR 3.8.4 Power for DAS automatic actuation functions required by TR 3.3.1 shall be FUNCTIONAL.
APPLICABILITY:
MODES 1, 2, 3, 4, and 5, MODE 6 with with upper internals in place, MODE 6 with cavity level < 23 feet above the top of the reactor vessel flange.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
Power to DAS Function not FUNCTIONAL.
A.1 Restore power supply to DAS to FUNCTIONAL status.
14 days TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.8.4.1 Verify power supply voltage at each DAS cabinet is 120 volts +/- 5%.
92 days
Technical Requirements Manual EDS TRM 3.8.4 VEGP Units 3 and 4 TRM 3.8.4 - 2 Revision 0 TRM 3.8.4 Non Class 1E DC and UPS System (EDS)
Bases The EDS function of providing power to DAS to support ATWS mitigation is important based on 10 CFR 50.62 (ATWS Rule) and to support ESFA is important based on providing margin in the PRA sensitivity performed assuming no credit for nonsafety-related SSCs to mitigate at-power and shutdown events. The margin provided in the PRA study assumes a minimum availability of 90% for this function during the Applicability, considering both maintenance unavailability and failures to operate.
The DAS uses a 2-out-of-2 logic to actuate automatic functions. EDS power is required for the DAS sensors, DAS actuation, and the devices which control the actuated components. Power may be provided by EDS to DAS by non-1E batteries through non-1E inverters. Other means of providing power to DAS include the spare battery through a non-1E inverter or non-1E regulating transformers.
The EDS support of the DAS ATWS mitigation function is required during MODE 1 when ATWS is a limiting event and during MODES 1, 2, 3, 4, 5, and 6 when ESFA is important. The DAS ESFA is required in MODE 6 with upper internals in place or with cavity level < 23 feet above the top of the reactor vessel flange. Planned maintenance should not be performed on a required EDS SSC during a required MODE of operation; planned maintenance should be performed on redundant supplies of EDS power.
Technical Requirements Manual Containment Penetrations TRM 3.9.1 VEGP Units 3 and 4 TRM 3.9.1 - 1 Revision 6 TRM 3.9 REFUELING OPERATIONS TRM 3.9.1 Containment Penetrations TR 3.9.1 The containment penetrations shall be in the following status:
- a.
The equipment hatches closed and held in place by four bolts or, if open, the Containment Air Filtration System (VFS) shall be FUNCTIONAL and operating;
- b.
One door in each air lock closed or, if open, the VFS shall be FUNCTIONAL and operating;
- c.
The containment spare penetrations closed or, if open, the VFS shall be FUNCTIONAL and operating;
- d.
Each penetration providing direct access from the containment atmosphere to the outside atmosphere is either:
- 1.
Closed by a manual or automatic isolation valve, blind flange, or equivalent, or
- 2.
VFS being FUNCTIONAL and operating.
- NOTE -
Penetration flow path(s) providing direct access from the containment atmosphere to the outside atmosphere may be unisolated under administrative controls.
APPLICABILITY:
During movement of irradiated fuel assemblies within containment.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
TR not met.
A.1 Suspend movement of irradiated fuel assemblies within containment.
Immediately
Technical Requirements Manual Containment Penetrations TRM 3.9.1 VEGP Units 3 and 4 TRM 3.9.1 - 2 Revision 6 TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.9.1.1 Verify each required containment penetration is in the required status.
7 days TRS 3.9.1.2
- NOTE -
Only required to be met if any TR items a through d has an open penetration.
Verify the required VFS can maintain a pressure
-0.125 inches water gauge relative to outside atmospheric pressure in the area enclosed by the containment and alternate barrier.
24 months TRS 3.9.1.3 Operate each required VFS train for 10 continuous hours with the heaters operating.
Within 31 days prior to fuel movement
Technical Requirements Manual Containment Penetrations TRM 3.9.1 VEGP Units 3 and 4 TRM 3.9.1 - 3 Revision 6 TRM 3.9.1 Containment Penetrations BASES BACKGROUND During movement of irradiated fuel assemblies within containment, potential releases of fission product radioactivity within containment are monitored and filtered or are restricted from escaping to the environment when the TR requirements are met. Monitoring of potential releases of radiation is performed in accordance with Technical Specifications (TS)
Section 5.5.2, Radioactive Effluent Control Program. In MODES 1, 2, 3, and 4, containment OPERABILITY is addressed in TS LCO 3.6.1, Containment. In MODES 5 and 6, closure capability of containment penetrations is addressed in TS LCO 3.6.7, Containment Penetrations. Since there is no potential for containment pressurization due to a fuel handling accident, the Appendix J leakage criteria and tests are not required in MODES 5 and 6.
The containment serves to contain fission product radioactivity that may be released from the reactor core following an accident, such that offsite radiation exposures are maintained within the requirements of 10 CFR 50.34. For a fuel handling accident, the Reference 1 analysis does not rely on containment closure to meet the offsite radiation exposure limits. This TR is provided as an additional level of defense against the possibility of a fission product release from a fuel handling accident.
The containment equipment hatches, which are part of the containment pressure boundary, provide a means for moving large equipment and components into and out of containment.
During movement of irradiated fuel assemblies within containment, an equipment hatch is considered closed if the hatch cover is held in place by at least four bolts. Good engineering practice dictates that the bolts required by this TR be approximately equally spaced.
If an equipment hatch is open, an alternative barrier between the containment atmosphere and the outside atmosphere shall be in place. Each containment equipment hatch opens into a staging area in the auxiliary building. These staging areas contain doors that open to the radiologically controlled areas of the annex building. The annex building contains a door that opens to the outside atmosphere. The alternate barrier may consist of the staging area in the auxiliary building, or may consist of the staging areas in the auxiliary building and the radiologically controlled areas in the annex building provided the doors from the annex building to the outside atmosphere are closed. The alternate barrier may also consist of a temporary equipment hatch cover that provides equivalent isolation capability. The alternate boundary prevents the airborne fission products from being readily released to the atmosphere if the equipment hatches were open during a fuel handling accident.
If an equipment hatch is open during movement of irradiated fuel assemblies within containment, the Containment Air Filtration System (VFS) shall be FUNCTIONAL, and at least one exhaust fan shall be operating to provide for monitoring of air-borne radioactivity. This system services the containment, and upon detection of high radiation, also services the fuel handling area, the auxiliary building (including the staging areas), and the annex building. If high airborne radioactivity is detected in the area enclosed by the alternate barrier, the
Technical Requirements Manual Containment Penetrations TRM 3.9.1 VEGP Units 3 and 4 TRM 3.9.1 - 4 Revision 6 BASES (continued)
Radiologically Controlled Area Ventilation System (VAS) supply and exhaust duct isolation dampers automatically close to isolate the affected area from the outside environment, and the VAS exhaust is automatically aligned to the VFS exhaust subsystem. The operation of the VFS exhaust fans provides the system with the ability for monitoring of radioactivity releases from containment following a fuel handling accident and, if operating, will provide filtration of the containment atmosphere.
If a personnel air lock, or containment spare penetration is open during movement of irradiated fuel assemblies within containment, then the VFS shall be FUNCTIONAL and operating to monitor for the release of radioactivity and to provide filtration of the air inside containment.
These penetrations open into the auxiliary building. Upon detection of high radiation in the exhaust air from the auxiliary building, VFS will provide filtered exhaust of these areas.
Considering that these penetrations open into the auxiliary building and not directly to the atmosphere, and that the VFS is in operation, an alternate barrier to the release of radioactivity directly to the environment is provided.
APPLICABLE SAFETY ANALYSES There are no safety analyses that require containment closure during movement of irradiated fuel assemblies within containment, other than those discussed in TS LCO 3.6.7. Fuel handling accidents, analyzed in Reference 1, include dropping a single irradiated fuel assembly and handling tool or a heavy object onto other irradiated fuel assemblies. The requirements of TS LCO 3.9.4, Refueling Cavity Water Level, ensure that the release of fission product radioactivity, subsequent to a fuel handling accident, results in doses that are well within the guideline values specified in 10 CFR 50.34. Standard Review Plan, Section 15.0.1 (Reference 2), defines the dose acceptance limit to be 25% of the limiting dose guideline values.
This TR is included as defense-in-depth.
TECHNICAL REQUIREMENT This TR provides defense-in-depth against the consequences of a fuel handling accident in containment by limiting the potential escape paths for fission product radioactivity released within containment. This TR requires that if an equipment hatch, personnel air lock, containment spare penetration, or penetration providing direct access from the containment atmosphere to the outside atmosphere is open during movement of irradiated fuel assemblies within containment, then the VFS shall be FUNCTIONAL and operating to monitor for the release of radioactivity and to provide filtration of the air inside containment.
The VFS is FUNCTIONAL when:
- a.
One VFS exhaust fan is operating; the associated HEPA filter and charcoal adsorber are not excessively restricting flow, and are capable of performing their filtration function; and air circulation can be maintained, including maintaining -0.125 inches water gauge relative to outside atmospheric pressure;
Technical Requirements Manual Containment Penetrations TRM 3.9.1 VEGP Units 3 and 4 TRM 3.9.1 - 5 Revision 6 BASES (continued)
- b.
An alternative barrier between the containment atmosphere and the outside atmosphere is in place. The alternate barrier may consist of the staging area in the auxiliary building, or may consist of the staging areas in the auxiliary building and the radiologically controlled areas in the annex building provided the doors from the annex building to the outside atmosphere are closed.
Doors in the alternate barrier which are normally closed may be opened for short periods of time for ingress and egress. The alternate barrier may also consist of a temporary equipment hatch cover that provides equivalent isolation capability.
APPLICABILITY The containment penetration requirements are applicable during movement of irradiated fuel assemblies within containment because this is when there is a potential for a fuel handling accident. In MODES 1, 2, 3, and 4, containment penetration requirements are addressed by TS LCO 3.6.1. In MODES 5 and 6, when movement of irradiated fuel assemblies within containment are not being conducted, the potential for a fuel handling accident does not exist.
Containment closure capability in MODES 5 and 6 are addressed by TS LCO 3.6.7.
ACTIONS The required status for the containment equipment hatch, air locks or spare penetration is either closed, or open with the VFS FUNCTIONAL and operating. The required status for the containment penetrations that provide direct access from the containment atmosphere to the outside atmosphere is either closed by a manual or automatic isolation valve, blind flange or equivalent, or open with the VFS FUNCTIONAL and operating. If the containment equipment hatch or air locks, or any containment penetration that provides direct access from the containment atmosphere to the outside atmosphere is not in the required status, the unit must be placed in a condition where the isolation function is not needed. This is accomplished by immediately suspending movement of irradiated fuel assemblies within containment.
Performance of these actions shall not preclude completion of movement of a component to a safe position.
Technical Requirements Manual Containment Penetrations TRM 3.9.1 VEGP Units 3 and 4 TRM 3.9.1 - 6 Revision 6 TECHNICAL REQUIREMENT SURVEILLANCE TRS 3.9.1.1 verifies that each of the containment penetrations required to be in its closed position is in that position or the VFS is FUNCTIONAL and operating. For the VFS to be considered FUNCTIONAL, this surveillance also requires that an alternate barrier is in place.
TRS 3.9.1.2 verifies the ability of the VFS to maintain a pressure -0.125 inches water gauge relative to outside atmospheric pressure in the containment and the portions of the auxiliary and/or annex building that comprise the envelope defined as the alternate barrier. This surveillance is performed with the VFS in containment operating. Doors in the alternate barrier which are normally closed may be opened for ingress and egress. The portion of the VAS which services the area enclosed by the alternate barrier is aligned to the VFS exhaust subsystem, and with VAS auxiliary/annex building supply fans and VFS containment purge supply fans not operating. The Frequency of 24 months is consistent with the guidance provided in NUREG 0800, Standard Review Plan, Section 6.5.1 (Ref. 3).
TRS 3.9.1.3 addresses that the VFS should be checked periodically to ensure that it functions properly. As the operating conditions on this system are not severe, testing each train within 31 days prior to fuel movement provides an adequate check on this system. Operation of the heater dries out any moisture accumulated in the charcoal from humidity in the ambient air.
REFERENCES
- 1.
FSAR Section 15.7.4, Fuel Handling Accident.
- 2.
NUREG-0800, Standard Review Plan, Section 15.0.1, Rev. 0.
- 3.
NUREG-0800, Standard Review Plan, Section 6.5.1, Rev. 2, July 1981.
Technical Requirements Manual VFS TRM 3.9.2 VEGP Units 3 and 4 TRM 3.9.2 - 1 Revision 6 TRM 3.9 REFUELING OPERATIONS TRM 3.9.2 Containment Air Filtration System (VFS)
TR 3.9.2 One VFS exhaust subsystem shall be FUNCTIONAL.
APPLICABILITY:
During movement of irradiated fuel assemblies in the fuel building.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.
Required VFS exhaust subsystem not FUNCTIONAL.
A.1 Suspend movement of irradiated fuel assemblies in the fuel building.
Immediately TECHNICAL REQUIREMENT SURVEILLANCE SURVEILLANCE FREQUENCY TRS 3.9.2.1 Operate required VFS exhaust subsystem for 10 continuous hours with the heaters operating.
Within 31 days prior to fuel movement TRS 3.9.2.2 Verify the VAS fuel handling area subsystem aligns to required VFS exhaust subsystem on an actual or simulated actuation signal.
24 months TRS 3.9.2.3 Verify required VFS exhaust subsystem can maintain a pressure -0.125 inches water gauge relative to outside atmospheric pressure in the fuel handling area.
24 months
Technical Requirements Manual VFS TRM 3.9.2 VEGP Units 3 and 4 TRM 3.9.2 - 2 Revision 6 TRM 3.9.2 Containment Air Filtration System (VFS)
BASES BACKGROUND The radiologically controlled area ventilation system (VAS) serves the fuel handling area of the auxiliary building, and the radiologically controlled portions of the auxiliary and annex buildings, except for the health physics and hot machine shop areas which are provided with a separate ventilation system (VHS). If high airborne radioactivity is detected in the exhaust air from the fuel handling area, the auxiliary building, or the annex buildings, the VAS supply and exhaust duct isolation dampers automatically close to isolate the affected area from the outside environment and the containment air filtration exhaust subsystem starts. The VFS exhaust subsystem prevents exfiltration of unfiltered airborne radioactivity by maintaining the isolated zone at -0.125 inches water gauge pressure relative to the outside atmosphere. Monitoring of potential releases of radiation is performed in accordance with Technical Specification (TS) 5.5.2, Radioactive Effluent Control Program.
For a fuel handling accident, the Reference 3 analysis does not rely on the FUNCTIONALITY of the VAS or VFS exhaust subsystem to meet the offsite radiation exposure limits. This TR is provided as an additional level of defense-in-depth against the possibility of a fission product release from a fuel handling accident in the fuel building. The plant vent radiation detectors monitor effluents discharged from the plant vent to the environment.
Each VFS exhaust subsystem includes one 100% capacity exhaust air filtration unit, and the associated exhaust fan, heater and ductwork.
The filtration units are connected to a ducted system with isolation dampers to provide HEPA filtration and charcoal adsorption of exhaust air from the containment, fuel handling area, radiologically controlled areas of the auxiliary and annex buildings. A gaseous radiation monitor is located downstream of the exhaust air filtration units to provide an alarm if abnormal gaseous releases are detected. The plant vent exhaust flow is monitored for gaseous, particulate and iodine releases to the environment. During conditions of abnormal airborne radioactivity in the fuel handling area, auxiliary and/or annex buildings, the VFS exhaust subsystem provides filtered exhaust to minimize unfiltered offsite releases.
The VAS is described in Reference 1 and the VFS is described in Reference 2.
APPLICABLE SAFETY ANALYSES The VFS is not required to mitigate the consequences of the limiting design basis accident (DBA), which is a fuel handling accident. The analysis of the fuel handling accident, given in Reference 3, assumes that all fuel rods in an assembly are damaged. The DBA analysis of the fuel handling accident does not assume that the VFS provides a filtered exhaust, and its operation would reduce the consequences of the fuel handling accident.
This specification is included for defense-in-depth.
Technical Requirements Manual VFS TRM 3.9.2 VEGP Units 3 and 4 TRM 3.9.2 - 3 Revision 6 BASES (continued)
TECHNICAL REQUIREMENT One VFS exhaust subsystem is required to be FUNCTIONAL to reduce the consequences of a fuel handling accident by filtering the fuel building atmosphere.
A VFS exhaust subsystem is considered FUNCTIONAL when its associated:
- a.
Exhaust fan is capable of operating, including maintaining -0.125 inches water gauge relative to outside atmospheric pressure;
- b.
HEPA filter and charcoal adsorber are not excessively restricting flow, and are capable of performing their filtration function;
- c.
The associated heater and ductwork are capable of operating.
APPLICABILITY During movement of irradiated fuel in the fuel handling area, one VFS exhaust subsystem is FUNCTIONAL to alleviate the potential consequences of a fuel handling accident.
ACTIONS When the required VFS exhaust subsystem is not FUNCTIONAL during movement of irradiated fuel assemblies in the fuel building, action must be taken to place the unit in a condition in which the TR does not apply. Action must be taken immediately to suspend movement of irradiated fuel assemblies in the fuel building. This does not preclude the movement of fuel to a safe position.
TECHNICAL REQUIREMENT SURVEILLANCE TRS 3.9.2.1 verifies the required VFS exhaust subsystem be checked 31 days prior to fuel movement in the fuel handling area to ensure that it functions properly. As the operating conditions on this subsystem are not severe, testing each subsystem within one month prior to fuel movement provides an adequate check on this system. Operation of the heater dries out any moisture accumulated in the charcoal from humidity in the ambient air.
TRS 3.9.2.2 verifies that the VAS fuel handling area subsystem aligns to the VFS and that the required VFS exhaust subsystem starts and operates on an actual or simulated actuation signal.
During the post-accident mode of operation, the VAS fuel handling area subsystem aligns to the VFS filtered exhaust subsystem. The 24 month Frequency is consistent with Reference 4.
TRS 3.9.2.3 verifies the integrity of the fuel handling area of the auxiliary building enclosure.
The ability of the VAS and VFS to maintain pressure -0.125 inches water gauge relative to outside atmospheric pressure in the fuel handling area of the auxiliary building is periodically tested to verify proper function of the VAS and VFS exhaust subsystem. During this surveillance, the VAS fuel handling area subsystem is aligned to the operating VFS exhaust subsystem. The fan for the VAS fuel handling area subsystem is off. In this configuration, the
Technical Requirements Manual VFS TRM 3.9.2 VEGP Units 3 and 4 TRM 3.9.2 - 4 Revision 6 BASES (continued) required VFS exhaust subsystem is designed to maintain a pressure in the fuel handling area of the auxiliary building -0.125 inches water gauge relative to outside atmospheric pressure, to prevent unfiltered and unmonitored leakage. Doors may be opened for short periods of time to allow ingress and egress. During this surveillance, the VAS may be servicing the remaining portions of the auxiliary and annex buildings. The Frequency of 24 months is consistent with the guidance provided in NUREG 0800, Standard Review Plan, Section 6.5.1 (Ref. 5).
REFERENCES
- 1.
FSAR Section 9.4.3, Radiologically Controlled Area Ventilation System.
- 2.
FSAR Section 9.4.7, Containment Air Filtration System.
- 3.
FSAR Section 15.7.4, Fuel Handling Accident.
- 4.
Regulatory Guide 1.140 (Rev. 2).
- 5.
NUREG 0800, Standard Review Plan, Section 6.5.1, Rev. 2, July 1981.