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Tech Specs 5 Flashcards

Instrumentation

1
Q

List the sections and subsections of the Instrumentation chapter of Tech Specs

A

3.3.1 Scram/NI Trip Functions
3.3.1.1 - Reactor Protection System Instrumentation
3.3.1.2 - Source Range Monitoring Instrumentation
3.3.1.3 - Oscillation Power Range Monitoring Instrumentation

3.3.2 Control Rod Trip Functions
3.3.2.1 - Control Rod Block Instrumentation

3.3.3 Really, Really Bad Day Stuff
3.3.3.1 - Post Accident Monitoring Instrumentation
3.3.3.2 - Remote Shutdown System Instrumentation

3.3.4 Recirc Pump Trip Functions
3.3.4.1 - EOC-RPT Instrumentation
3.3.4.2 - ATWS-RPT Instrumentation

3.3.5 Water Inventory Trip Functions
3.3.5.1 - ECCS Instrumentation
3.3.5.2 - RPV Water Inventory Control Instrumentation
3.3.5.3 - RCIC Instrumentation

3.3.6 Containment and Drywell Trip Functions
3.3.6.1 - Containment and Drywell Isolation Instrumentation
3.3.6.2 - RHR Containment Spray Instrumentation
3.3.6.3 - SPMU Instrumentation
3.3.6.4 - LLS Valves Instrumentation

3.3.7 Control Room Ventillation Trip Functions
3.3.7.1 - Control Room Emergency Recirc Instrumentation

3.3.8 Electrical Trip Functions
3.3.8.1 - Loss of Power Instrumentation
3.3.8.2 - RPS Electric Monitoring Instrumentation

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2
Q

3.3.1.1 Reactor Protection Instrumentation

State the LCO.

List the functions included in this system.

A

LCO
The RPS instrumentation for each Function in table 3.3.1.1-1 shall be operable.

Functions
1. IRM Trips
 Neutron Flux High
 Inop
2. APRM Trips
 Nuetron Flux High, Setdown
 Flow Biased Simulated Thermal Power High
 Fixed Neutron Flux High
 Inop
3. Reactor Vessel Steam Dome Pressure High
4.Reactor Vessel Water Level Low
5.Reactor Vessel Water Level High
6. MSIV Closure
7. Drywell Pressure High
8. SDV Level High
 Transmitter/Trip Unit
 Float Switch
9. TSV Closure
10. TCV Fast Closure Trip, Oil Pressure Low
11. Reactor Mode Switch - Shutdown
12. Manual Scram

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3
Q

3.3.1.1Reactor Protection Instrumentation

This LCO has various requirements for condition entries that require action in 1 hour or less.

Discuss what these actions are and how they are entered.

A

This LCO has a ladder of actions that work through conditions to ensure safe operation. Actions A, B, & C deal with the loss of a required channel, trip system, and function respectively.

If any function of the RPS instrumentation does not have trip capability, it must be restored within 1 hour.

If any of the actions required for these three conditions are not completed IAW completion time requirement, Action D is entered immediately.

Action D directs follow-up condition entry based on affected channels, trip systems, and/or functions.

If any of these follow-up condition actions are not completed IAW completion time requirement, initiate action to fully insert all insertable control rods in core cells containing one or more fuel assemblies.

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4
Q

3.3.1.1 Reactor Protection System Instrumentation

What requirements exist for APRM indication vs calculated reactor power?

A

If ≥ 23.8% RTP, APRMs must read within 2% of calculated reactor power.

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5
Q

3.3.1.1 Reactor Protection System Instrumentation

Six functions of the RPS instrumentation are required in specific circumstances in Mode 5.

What are they, what circumstances are they required for?

A

IRM Neutron Flux High
IRM Inop
SDV Transmitter/Trip Unit
SDV Float Switch
Rx Mode Sw - Shutdown
Manual Scram

They are required in mode 5 with any control rod withdrawn from a core cell containing one or more fuel assemblies.

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6
Q

3.3.1.1 RPS Instrumentation Bases

The RPS inserts the scram when monitored parameters exceed their trip values.

What is the basis of this operation?

A

Scram preserves the integrity of fuel cladding and minimizes required energy absorbtion in a LOCA.

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7
Q

3.3.1.1 RPS Instrumentation Bases

Regarding trip setpoints, what makes instrumentation inoperable?

A

Channel is inoperable if its actual trip setpoint is not within its required Allowable Value.

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8
Q

3.3.1.1 RPS Instrumentation Bases

For each function in the RPS System Instrumentation, state the basis for its operability requirement.

A

IRM Nuetron Flux High - Provides protection against local rod withdrawal errors.
IRM Inop - Function is not assumed in safety analysis, therefor required to be operable to satisfy analysis.
APRM Neutron Flux High Setdown - Prevents exceeded 23.8% RTP before mode switch is in Run, which prevents fuel damage during significant reactivity increases with low reactor pressure and low core flow. This is not considered in the Safety Analysis
Flow Biased Simulated Thermal Power High - Provides protection against transients where thermal power increases slowly, protecting the MCPR SL.
APRM Fixed Neutron Flux High - Provides overpressure protection from a sudden MSIV closure event.
APRM Inop - Three trip channels of APRMs are required to be operable. With more than one trip channel inoperable, this requirement is not satisfied. This requirement is not considered in the safety analysis, but is required by the NRC approved licensing basis.
Steam Dome Pressure High - This trip function does not have any specific safety analysis associated with it, as the overpressure protection function is covered by the APRM Fixed Neutron High Flux trip. It serves the same function as this trip, inserting a scram on an overpressure condition to counteract the positive reactivity added by the pressure transient.
Vessel Water Level Low - The water level limit coupled with the ECCS systems and the scram ensures peak fuel cladding temperature remains below limit during a DBA LOCA. The water limit is also high enough that in a loss of all normal feedwater flow, a Level 1 ECCS initiation will not be required.
Vessel Water Level High - Ensures MCPR is not violated.
MSIV Closure - Protects peak fuel cladding temperature but is not credited in analysis for the overpressure condition (APRM Flux High is). Also protects violation of safety limit due to low pressure MSIV closure.
Drywell Pressure High - Prevent fuel damage and minimize energy added to the coolant and drywell in a DBA LOCA.
SDV Level High - No credit is taken for this in analysis, but ensures SDV has sufficient room to receive scram effluent.
TSV Closure - Primary scram signal for the turbine trip event analyzed.
TCV Closure - Primary scram signal for the generator load rejection event.
Mode Switch in SD - Not specifically credited, required for NRC approved licensing basis.
Manual Scram - Not credited, required for NRC approved licensing basis.

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9
Q

3.3.1.1 RPS Instrumentation Bases

List the required operable channels for all functions in the RPS Instrumentation section.

A

For all NI related functions - 3 channels per trip system.
For MSIV closure function - 8 channels per trip system.
For TSV closure - 4 channels per trip system.
All other functions - 2 channels per trip system.

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10
Q

3.3.1.1 RPS Instrumentation Bases

Some trip functions have abnormal applicability requirements (they aren’t based on mode). Which trip functions are these?

A

Vessel Level High only required ≥ 23.8% RTP.
TSV & TCV trip functions only required ≥ 38% RTP.

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11
Q

3.3.1.1 RPS Instrumentation Bases

Which trip functions are only applicable in Mode 1?

A

APRM Fixed Neutron Flux High
MSIV Closure

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12
Q

3.3.1.1 RPS Instrumentation Bases

The Vessel Water level high function is not installed to prevent turbine carry-over issues.

The basis of this function is to protect MCPR - so how is maintaining water level below L8 protecting MCPR?

A

The higher level of water results in the addition of relatively cold feedwater, resulting in reactivity addition that challenges MCPR limits.

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13
Q

3.3.1.1 RPS Instrumentation Bases

How many LPRMs must be operable for an APRM to be considered operable?

How is this restriction enforced?

A

14 LPRMs must be operable, and at least 2 per axial zone on that APRM must be operable.

With < 14 LPRMS operable, the APRM will trip as inoperable.

The 2 LPRMs per axial zone requirement does not have a trip feature. This must be monitored by administrative means.

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14
Q

3.3.1.1 RPS Instrumentation Bases

What provisions does this LCO make for performing Surveillences on the applicable equipment?

A

When a channel must be placed in trip for surveillance, condition entry may be delayed for up to 6 hours provided the associated function maintains trip capability.

Upon completion or the 6 hour limit, channel must be returned to Operable or applicable condition must be entered.

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15
Q

3.3.1.1 RPS Instrumentation Bases

The followup conditions entered through Condition D when Actions of A/B/C are not complete have various power reduction requirements that have to be completed anywhere between 4 hours and 12 hours.

What is the time critical requirement to BEGIN these required actions?

A

15 minutes

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16
Q

3.3.1.1 RPS Instrumentation Bases

The APRMs have a requirement to be within ± 2% of the heat balance calculated reactor power.

When outside these bounds, when are the APRMs NOT considered inoperable?

A

When APRMs fall outside this band, they are not considered inoperable from either side.

If the APRMs are LESS conservative, they must be adjusted consistent with the heat balance calculated power. If they can not be properly adjusted, the channel is then declared inoperable.

If the APRMs are MORE conservative, the agreement between APRM & Heat Balance is not required for operability.

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17
Q

3.3.1.2 SRM Instrumentation

State the LCO

What functions exist in the table stated in the LCO.

A

LCO
SRM Instrumentation in table 3.3.1.2-1 shall be operable.

Functions
Source Range Monitor

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18
Q

3.3.1.2 SRM Instrumentation

The Source Range Monitor function is the only function with a requirement in this LCO. However, it has various channel requirements and applicabilities. What are they?

A

Mode 2: 3 channels when IRMs are on Range 2 or below.

Modes 3 & 4: 2 channels required.

Mode 5: 2 channels.

*Note: Only one operable channel is required during spiral offload when the fueled region includes only that detector.
Note 2: Special movable detectors may be used in place of SRMs if connected to normal SRM circuits.

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19
Q

3.3.1.2 SRM Instrumentation

What is the lower threshold indication for an SRM to be considered operable?

A

Count rate ≥ 3.0 cps or
≥ 0.7 cps with a signal/noise ratio ≥ 2:1

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20
Q

3.3.1.2 SRM Instrumentation

When performing core alterations, which SRM detectors must be operable?

A

Must have a detector(s) in:
The quadrant where core alterations are being performed and a FUEL CONTAINING quadrant adjacent to the quadrant undergoing core alterations.

If in a condition where only 1 SRM is required, the quadrant adjacent requirement is not applicable.

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21
Q

3.3.1.2 SRM Instrumentation

Discuss any conditions requiring actions performed in 1 hour or less.

A

Condition B: With three required SRMs inoperable in Mode 2 & IRMs on Range 2 or below, immediately suspend control rod withdrawal.

Condition D:
With one or more required SRMs inoperable in Modes 3 or 4, fully insert all insertable control rods and place the mode switch in shutdown within 1 hour.

Condition E:
With one or more required SRMs inoperable in Mode 5, immediately suspend core alterations except for control rod insertion and initiate action to fully insert all insertable control rods in core cells containing one or more fuel assemblies.

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22
Q

3.3.1.2 SRM Instrumentation Bases

What is the basis for requiring 3 SRM instrumentation channels operable in Mode 2?

A

Reactivity changes in Mode 2 are complex. 3 of 4 channels will provide sufficent representation of overall core response to reactivity manipulations.

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23
Q

3.3.1.2 SRM Instrumentation Bases

What is the basis of reducing the SRM requirement to 1 instrument in Mode 5 during spiral offload?

A

Eventually, the core gets to a point where only one quadrant is fueled. At this point, any SRM outside of the fueled region will not provide an accurate representation of core flux, thus, the reduction in requirement.

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24
Q

3.3.1.2 SRM Instrumentation Bases

What constitutes an operable SRM Instrument channel?

A

It must provide neutron flux monitoring indiciation. In order to perform this function it must be inserted to the normal operating level and there must be continuous visual indication in the control room.

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25
Q

3.3.1.3 OPRM Instrumentation

List the LCO and Applicability

A

LCO
Four channels of the OPRM Perioud Based Algorithm instrumentation must be operable.

Applicability
Thermal power ≥ 23.8% RTP.

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26
Q

3.3.1.3 OPRM Instrumentation Bases

What three algorithms do the OPRMs use to monitor for oscillations?

A

Period
Amplitude
Growth

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27
Q

3.3.1.3 OPRM Instrumentation Bases

Why is there only a requirement for the Period algorithm?

What is the purpose of the other algorithms?

A

Amplitude and growth are not considered in the safety analysis, and therefore must not be met.

These algorithms provide defense in depth and additional protection against unanticipated oscillations.

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28
Q

3.3.1.3 OPRM Instrumentation Bases

What do the OPRMs protect?

4 Channels of these instruments are required to be operable. Each channel is made up of multiple modules. How many modules are required for operability?

A

The OPRMs protect the MCPR safety limit.

There are two modules for period based detection, and only one is required for OPRM channel operability.

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29
Q

3.3.1.3 OPRM Instrumentation Bases

Why are the OPRMs not required below 23.8% RTP?

A

At this point, MCPR is no longer a concern.

30
Q

3.3.2.1 Control Rod Block Instrumentation

State the LCO.

What Functions are this LCO covering?
What do these functions protect from?

A

LCO
The control rod block instrumentation for each Function in table 3.3.2.1-1 shall be operable.

Functions
Rod Pattern Control System
 Rod Withdrawal Limiter - Rod Withdrawal Error
 Rod Pattern Controller - Control Rod Drop Accident
Reactor Mode Switch - Shutdown Position - Maintaining the Reactor shutdown

31
Q

3.3.2.1 Control Rod Block Instrumentation

The Rod Withdrawal Limiter has 2 different applicabilities.

What are these applicabilities and why are they different?

A

Thermal Power > 66.7% RTP &
Thermal Power > 33.3% & ≤ 66.7% RTP.

There is a 4 notch withdrawal limit between 19% & 66.7% RTP.
There is a 2 notch withdrawal limit above 66.7% RTP.

32
Q

3.3.2.1 Control Rod Block Instrumentation

List all conditions with actions requiring completion in 1 hour or less.

A

Condition A:
With one or more rod withdrawal limiter channels inoperable, suspend control rod withdrawal immediately.

Condition B:
With one or more rod pattern controller channels inoperable, immediately suspend control rod movement except by scram.

Condition C:
With one or more Reactor Mode Switch - Shutdown Position channels inoperable, immediately suspend control rod withdrawal and initiate action to fully insert all insertable control rods in core cells containing one or more fuel assemblies.

33
Q

3.3.2.1 Control Rod Block Instrumentation Bases

What does the Rod Withdrawal Limiter requirement protect from?

A

Violation of the MCPR safety limit and the cladding 1% plastic strain fuel design limit that may result from a single control rod withdrawal error.

34
Q

3.3.2.1 Control Rod Block Instrumentation Bases

The BPWS is only applicable at ≤ 19% RTP.
Between this power level and 33% RTP, Rod Withdrawal Limiter Instrumentation is NOT required to be operable.

Why does this gap in the LCO exist?

A

Below 33% RTP, the consequences of the Rod Withdrawal Event will not exceed the MCPR safety limit.

35
Q

3.3.2.1 Control Rod Block Instrumentation Bases

Conditions of LCO 3.1.3 or 3.1.6 may necessitate bypassing individual control rods to complete actions and allow continued operation with inoperable control rods.

What allows these conditions to conform to the requirements of this LCO?

A

Individual rods may be bypassed as required by those conditions. The Rod Pattern Controller is not considered inoperable provided Surveillence 3.3.2.1.9 is met.

This surveillence requires a second licensed operator or qualified member of the technical staff to verify the bypassing and movement of control rods required to be bypassed in RACS is in conformance with applicable analyses.

36
Q

3.3.2.1 Control Rod Block Instrumentation Bases

The Rod Withdrawal Limiter senses first stage turbine pressure to implement its function. What vulnerabilities exist with this method of sensing and what preventative measures must be taken to account for it?

A

If the main turbine bypass valves are not fully closed, the RWL does not have an accurate representation of actual thermal power.

When RTP is above the LPSP, the RWL is considered inoperable, and control rod withdrawal shall be prevented in the above conditions and verified by a second licensed operator or technically qualified member of the unit staff.

37
Q

3.3.2.1 Control Rod Block Instrumentation Bases

When a control rod is inoperable, how is the BPWS and Rod Pattern Controller effected?

A

When a control rod becomes inoperable while BPWS is enforced, the rod can not be inserted or withdrawn outside the pattern the BPWS enforces.

SR 3.3.2.1.9 allows for the bypassing of the rod in the RACS with concurrence from a second licensed operator.

38
Q

3.3.2.1 Control Rod Block Instrumentation Bases

The LPSP & HPSP function off of turbine first stage pressure. These features enable/disable the RPC and RWL.

How are the RPC & RWL effected by inaccuracies with these setpoints?

What, in particular, is different between the RPC & RWL regarding these sepoints?

A

If either setpoint is non-conservative (the indicated pressure correspondence to reactor power is less than actual), the functions are considered inoperable.

The HPSP only effects one function- the RWL. If the HPSP is conservative, the RWL is not necessarily considered inoperable- the surveillence is met.

The LPSP channel has an upper and lower bounds. It can not be placed in a conservative condition without placing its opposite bounds in a non-conservative condition.

39
Q

3.3.3.1 PAM Instrumentation

State the LCO and Applicability.

What functions are listed in the table?

A

LCO
The PAM Instrumentation for each Function in table 3.3.3.1-1 shall be operable.

Applicability
Modes 1 & 2

Functions
1. Steam Dome Pressure
2. Wide Range Level
3. Fuel Zone Level
4. SP water level
5. SP water temperature
6. Drywell Pressure
7. Drywell Air Temp
8. Primary Containment/Drywell Area Gross Gamma Radiation Monitors
9. PCIV Position
10. Containment Pressure
11. Containment Air Temp

40
Q

3.3.3.1 PAMs Instrumentation Bases

How many channels for each function must be operable?

Where is an exception made?

A

2 for all channels except PCIVs

PCIVs only require two channels per penetration flowpath unless;
The flowpath is known to be isolated, in which case no channels are required and;
The flow path only has one installed control room indication, in which case only one channel is needed.

41
Q

3.3.3.1 PAMs Instrumentation Bases

How do the Primary Containment and Drywell Gross Gamma Radiation Instruments work?

A

They have 2 separate detectors that transmit to the control room.

42
Q

3.3.3.2 Remote Shutdown System Bases

List the LCO and Applicability

A

LCO
The Remote Shutdown System Functions shall be operable.

Applicability
Modes 1 & 2

43
Q

3.3.3.2 Remote Shutdown System Bases

What is the design capability of the Remote Shutdown system?

A

Provide capability to promptly shut down the reactor to Mode 3 and maintain the plant in a safe condition in that mode.

44
Q

3.3.4.1 EOC-RPT Instrumentation

List the LCO and Applicability

A

LCO
Two channel per trip system for each EOC-RPT instrumentation Function listed below shall be operable:
a. TSV closure
b. TCV fast closure, trip oil pressure-low

Applicability
Thermal Power ≥ 38% RTP with any recirc pump in fast speed.

45
Q

3.3.4.1 EOC-RPT Bases

What limit does the EOC-RPT protect from?

A

Violation of MCPR Safety Limit

46
Q

3.3.4.1 EOC-RPT Bases

What components cause the recirc pumps to trip?

Are they included in operability of the trip channels?

A

The 3 & 4 breakers.

Yes.

47
Q

3.3.4.2 ATWS-RPT

List the LCO and Applicability

List any actions with completion time requirements 1 hour or less.

A

LCO
Two channels per trip system for each ATWS-RPT instrumentation Function listed below shall be operable:
a. Vessel Water Level Low Low -Level 2
b. Vessel Pressure High

Applicability
Mode 1

1 Hour or Less Actions
If both functions with ATWS-RPT trip functions not maintained, restore the trip capability for one function within 1 hour.

48
Q

3.3.4.2 ATWS-RPT Bases

What is the design basis of the ATWS-RPT?

A

Trip Recirc pumps when a scram does not (but should have) occur to insert negative reactivity and lessen effects of the ATWS.

49
Q

3.3.4.2 ATWS-RPT Bases

In order to consider the ATWS-RPT operable, the recirc pump drive motor breakers must be operable.

What breakers are these?

A

1-4 Breakers for the recirc pumps.

50
Q

3.3.5.1 ECCS Instrumentation

State the LCO

List the Functions covered by this LCO

A

LCO
The ECCS Instrumentation for each Function in table 3.3.5.1-1 shall be operable.

Functions
See Below

51
Q

3.3.5.1 ECCS Instrumentation

What modes are all ECCS system instrumentation requirements applicable?

Are there any exceptions?

A

Modes 1, 2, & 3.

ADS is not applicable when ≤ 150 psig steam dome pressure.

52
Q

3.3.5.1 ECCS Instrumentation

Certain functions in ECCS instrumentation are also required to initiate their associated diesel generator.

Which functions are they?

A

The Vessel Level Low and Drywell Pressure High functions for each Spray/Injection system.

53
Q

3.5.5.1 ECCS Instrumentation

Discuss navigation of the conditions in this LCO.

A

Condition A directs entry into applicable condition based on table channel requirements (i.e. entry into Condition B if minimum channel requirement not met for HPCS Drywell Pressure High).

54
Q

3.3.5.1 ECCS Instrumentation

In this LCO, Conditions B, C, & E contain an Action - 1 Hour from discovery of loss of initiation capability for both feature(s) in both divisions:

“Declare supported feature(s) inoperable when its redundant feature ECCS initiation capability is inoperable”

Explain what this means.

A

The ECCS LPCI systems are redundant to each other. If a channel is inoperable in one division and its redundant feature is inoperable, supported features covered by those channels must be declared inoperable within 1 hour.

This will result into the applicable condition entry in LCO 3.5.1 ECCS Operability

55
Q

3.3.5.1 ECCS Instrumentation

Discuss the 1 hour or less actions applicable to HPCS system.

A

If any function is inoperable, declare HPCS inoperable within 1 hour of discovery with these exceptions:
- HPCS Pump aligned to suppression pool
*- Vessel Level High (has no effect on automatic initiation).

56
Q

3.3.5.1 ECCS Instrumentation

Discuss the 1 hour or less actions associated with RHR and LPCS.

A

If any function is inoperable, and it is discovered that its redundant feature is inoperable, declare the supported feature (LPCI, LPCS) inoperable within 1 hour of discovery.

57
Q

3.3.5.1 ECCS Instrumentation

Discuss the 1 hour or less actions associated with ADS.

A

If the Vessel Level Functions, Timer Functions, or ECCS Low Pressure Permissive Functions are inoperable, if both channels are unable to initiate, declare ADS valves inoperable within 1 hour.

58
Q

3.3.5.1 ECCS Instrumentation Bases

What is the overall purpose of ECCS?

A

Preserve integrity of fuel cladding by limiting the post LOCA peak cladding temperature to less than limits.

59
Q

3.3.5.1 ECCS Instrumentation Bases

ECCS instrumentation functions also initiate other systems. What systems do they initiate?

A

DGs and AEGTs

60
Q

3.3.5.1 ECCS Instrumentation Bases

How can a single Time Delay Relay for the low pressure ECCS pumps render 2 pumps inoperable?

A

If one time delay relay is inoperable, it is possible that two ECCS pumps could attempt to start at the same time on the same ESF bus.

61
Q

3.3.5.2 RPV Water Inv Control Instrumentation

State the LCO, Functions, and their Applicabilities.

How many channels for each Function are required to be operable?

List any actions with a required completion time of 1 hour or less.

A

LCO
The RPV Water Inventory Control Instrumentation for each Function below shall be operable.

Functions
1. RHR System Isolation - Vessel Level Low L3
2. RWCU System Isolation - Vessel Level Low L2

Applicability
Each function is required to be operable when automatic isolation of the associated penetration flowpath is credited in calculating DRAIN TIME.

Required Channels
2 Channels in 1 trip system

1 Hour or Less Actions
With one or more required channels inoperable, immediately perform the following:
1. Initiate Action to place channel in trip
OR
2. Declare associated penetration flow path(s) incapable of automatic isolation
 AND
Initiate action to calculate drain time.

62
Q

3.3.5.2 RPV Water Inventory Control Instrumentation Bases

What does this LCO protect?

A

Protects the Safety Limit 2.1.1.3 and fuel cladding barrier to prevent release of radioactive material should a draining event occur.

63
Q

3.3.5.2 RPV Water Inventory Control Instrumentation Bases

Why are the automatic initiation instrumentation Functions of the ECCS systems not required in Modes 4 and 5?

A

It is assumed, based on engineering judgement, that in modes 4 & 5, one ECCS injection/spray subsystem can be manually initiated to maintain adequate reactor vessel water level.

64
Q

3.3.5.2 RPV Water Inventory Control Instrumentation Bases

Why are the RWCU and RHR Vessel Level Low L3/2 functions required?

A

Drain time calculation allows crediting of these systems (which are normally operating in some form) provided they are capable of automatically isolating.

65
Q

3.3.5.3 RCIC System Instrumentation

State the LCO and Applicability.

What Functions are covered by this LCO? State their required channels.

A

LCO
The RCIC System Instrumentation for each Function in Table 3.3.5.3-1 shall be operable.

Applicability
Mode 1
Modes 2 & 3 with reactor steam dome pressure > 150 psig.

Functions
Vessel Level Low L2 - 4
Vessel Level High L8 - 4
CST Level Low - 2
SP Level High - 2
Manual - 1

66
Q

3.3.5.3 RCIC System Instrumentation

Discuss conditions with actions requiring completion within 1 hour.

A

If the Vessel Level Low L2 Function is inoperable, declare RCIC system inoperable within 1 hour of discovery.

If the CST Auto Change feature Functions are inoperable and the RCIC system is NOT aligned to the SP, declare RCIC system inoperable within 1 hour of discovery.

67
Q

3.3.5.3 RCIC System Instrumentation Bases

What are the consequences of overriding the auto-changeover feature of the RCIC SP and CST suction isolations?

A

The SP Level High Functions become inoperable.

Changing suction source to CST manually will cause entry into Condition D.

68
Q

3.3.6.1 Containment and Drywell Isolation Instrumentation

State the LCO.

List any conditions with actions requiring completion time in 1 hour or less

A

LCO
The primary containment and drywell isolation instrumentation for each Function in Table 3.3.6.1-1 shall be operable.

1 Hour or Less Actions
With one or more automatic Functions with isolation capability not maintained, restore isolation capability within 1 hour.

If unable to complete this action regarding SLC initiation, either declare SLC inoperable or isolate the RWCU system within 1 hour.

If unable to complete this action for virtually every other penetration flow path (except for a few special circumstances and all MSL Functions) isolate the effected flow path within 1 hour.

69
Q

3.3.6.1 Primary Containment and Drywell Isolation Instrumentation Bases

What are the purposes of the PCIVs and DIVs?

A

PCIV - In combination with other systems, limit fission product release during and following postulated DBA.

DIV - In combination with other systems, ensure that steam and water releases to the drywell are channeled to the SP to maintain pressure suppression function of the drywell.

70
Q

3.3.6.1 Primary Containment and Drywell Isolation Instrumentation Bases

Some penetration flow paths only have a single automatic isolation valve or do not have redundant isolaion channels.

How is isolation capability of those paths maintained?

A

Maintained if those single valves can receive an isolation signal from the given Function.

71
Q
A

ILO24 (17 decks)

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