EOP Week 2 & 3

Question 1

What are the SI termination criteria given in ES-1.1 (SI Termination)

Answer 1

• Subcooling greater than 40 deg F
• Heat Sink Established (240k PPH OR 13% [28% ADVERSE] NR Lvl)
• RCS Pressure Stable or Rising
• Prz Level greater than 16% (20%) OR ADVERSE 28% (24%)

Question 2

While in E-1 (Loss of Reactor or Secondary Coolant) what actions are taken if the SG pressure boundary IS NOT intact

Answer 2

• If the faulted SG IS NOT isolated then go to E-2 (Faulted SG)

Question 3

While in E-1 (Loss of Reactor or Secondary Coolant) what actions are taken if the SG levels are NOT intact

Answer 3

• Maintain feed flow greater than 240k PPH until 13% [28% ADVERSE] NR Lvl
• If level rises in an uncontrolled manner then go to E-3 (SG Tube Rupture)

Question 4

While in E-1 (Loss of Reactor or Secondary Coolant) what actions are taken if subcooling, heat sink, RCS pressure, and Pzr Level are satisfactory

Answer 4

• Go to ES-1.1 (SI Termination)

Question 5

In E-1 (Loss of Reactor or Secondary Coolant) what is the purpose of the procedure loop that has you check:

• SG Pressure Stable OR Rising
• RCS Pressure Stable OR Lowering

AND what would the consequence be if you proceeded on with either condition NOT MET (i.e., instead of going to the RNO)

Answer 5

• If SG Pressure is lowering then you need to re-check for a faulted SG
• If RCS Pressure is Rising then you need to re-check if SI termination criteria are met
• Proceeding past this step will transition you to ES-1.2 (Post LOCA Cooldown and Depressurization) which has MORE restrictive SI termination criteria than needed

Question 6

While in E-1 (Loss of Reactor or Secondary Coolant) what actions are taken if Cold Leg Recirc capability is unavailable

Answer 6

• Go to ECA-1.1 (Loss of Emergency Coolant Recirc)

Question 7

In E-1 (Loss of Reactor or Secondary Coolant) what actions are taken if there is an Aux Building LOCA

Answer 7

• If ES-1.3 (transfer to Cold Leg Recirc) HAS been completed continue with E-1 (Loss of Reactor or Secondary Coolant) while the PET evaluates the leakage
• If ES-1.3 (Transfer to Cold Leg Recirc) HAS NOT been completed go to ECA-1.2 (LOCA Outside Containment)

Question 8

In E-1 (Loss of Reactor or Secondary Coolant) what actions are taken if RCS pressure is greater than the shutoff head of the RHR pumps (300#)

Answer 8

• Go to ES-1.2 (Post LOCA Cooldown and Depressurization)

Question 9

In E-1 (Loss of Reactor or Secondary Coolant) what actions are taken if RWST level is less than 30%

Answer 9

• Go to ES-1.3 (Transfer to Cold Leg Recirculation)

Question 10

In E-1 (Loss of Reactor or Secondary Coolant) what actions are taken at 7 hours after the event

Answer 10

• Go to ES-1.4 (Transfer to Hot Leg Recirculation)

Question 11

In ES-1.2 (Post LOCA Cooldown and Depressurization) what actions are taken if Cold Leg Recirc capability is unavailable

Answer 11

• Go to ECA-1.1 (Loss of Emergency Coolant Recirculation)

Question 12

In ES-1.2 (Post LOCA Cooldown and Depressurization) what actions are taken if there is an Aux Building LOCA

Answer 12

• Consult with the PET to determine source of leakage and go to ECA-1.2 (LOCA Outside Containment)

Question 13

While in ES-1.2 (Post LOCA Cooldown and Depressurization) what actions are taken if the SG levels are NOT intact

Answer 13

• Maintain feed flow greater than 240k PPH until 13% [28% ADVERSE] NR Lvl
• If level rises in an uncontrolled manner then go to E-3 (SG Tube Rupture)

Question 14

In ES-1.2 (Post LOCA Cooldown and Depressurization) after the cooldown is started and subcooling is verified greater than 40 deg F what actions is taken if ECCS is in service

Answer 14

• RCS Depressurization using Pzr Spray/PORVs begins

Question 15

In ES-1.2 (Post LOCA Cooldown and Depressurization) ANY time after SI has been reset AND ECCS pumps have been removed what actions are required if subcooling is lost OR Pzr Level is less than 20% [24% ADVERSE]

Answer 15

• ECCS flow must be MANUALLY established

Question 16

In FR-Z.1 (Response to High Containment Pressure) if ECA-1.1 (Loss of Emergency Coolant Recirc) is in effect what actions are required

Answer 16

• Operate CTS in accordance with ECA-1.1 (Loss of Emergency Coolant Recirc) while continuing in FR-Z.1

Question 17

When do you enter FR-Z.1 (Response to High Containment Pressure)

Answer 17

• Anytime Containment Pressure has risen to greater than 2.8#

Question 18

While in E-1 (Loss of Reactor or Secondary Coolant) after transfer to Cold Leg Recirc is complete, what conditions would require a transition to ECA-1.3 (Sump Blockage)

Answer 18

• 1 train of RHR/CTS and the low sump light is LIT

- Indications of cavitation on any RHR/CTS pump

Question 19

What are the four phases of a LBLOCA

Answer 19

• Blowdown (RCS Press = Cont Press)
• Refill (Water reaches bottom of fuel)
• Reflood (CETC stop rising)
• Long Term Recirc

Question 20

What are the three phases of a SBLOCA

Answer 20

• Blowdown (Break flow = ECCS flow)
• Reflood (CETC stop rising)
• Long Term Recirc

Question 21

During a SBLOCA why is a Cold Leg Break the worst location for a break

Answer 21

• The cross under piping creates a loop seal which prevents de-pressurization

Question 22

In ES-1.2 (Post LOCA Cooldown and Depressurization) why is more subcooling required when there are NO RCPs running

Answer 22

• With no RCPs running cooling is by Natural Circ
• Natural Circ results in colder CL temps
• Colder CL temps means density is greater and therefore, more break flow
• More break flow means a greater pressure reduction is required to establish equilibrium
• Greater pressure reduction means more subcooling required

Question 23

Why are RCPs stopped when RCS pressure is less than 1300#

Answer 23

• This ensures that they are stopped before the break is uncovered.
• Since RCP busses are non-safety have to assume they will be lost.
• If lost after the break is uncovered, more mass loss would occur uncovering more fuel (2 phase flow would separate)

Question 24

What are the time critical actions during ES-1.3 (Transfer to Cold Leg Recirc)

Answer 24

• 5 minutes with no RHR flow (no challenge to PCT)
• 5 minutes with no CTS flow
• 15 minutes to split CCW to prevent runout
• 5 minutes to isolate CTS from SAT

Question 25

Why are you required to wait 50 minutes before establishing RHR spray

Answer 25

- Allows adequate time for decay heat removal

Question 26

Why are you required to wait 6 hours to place H2 recombiners in service

Answer 26

- To avoid peak containment pressure at 6 hours (heat input)

Question 27

Why is CTS/RHR spray required to be in service for 24 hours

Answer 27

- Minimize control room dose

Question 28

During a SI how long do you have to start and continuously monitor PACHMS

Answer 28

- 90 minutes

Question 29

What size hole in the RCS is considered a SBLOCA

Answer 29

- Greater than 3/8"

Question 30

What size hole in the RCS is considered a LBLOCA

Answer 30

- Greater than 1 ft^2

Question 31

What are the 10 CFR 50.46 ECCS acceptance criteria

Answer 31

- 2200 deg F Peak Clad Temperature - 17% cladding oxidation - 1% H2 generation - Coolable geometry - Long Term Cooling

Question 32

What is reflux cooling/boiling

Answer 32

- Break doesn't removal all the heat - RCS is saturated - Steam in the SG tubes condenses and falls back through the HL - No natural circ

Question 33

What is the unique indication for a Pressurizer Steam space LOCA (e.g., Open PORV)

Answer 33

- Pressurizer Level will rise due to RCS at saturation causing swell - Pressurizer Pressure will lower

Question 34

What are the time critical actions on an inadvertent SI

Answer 34

- 15 minutes stop all but 1 CCP - 17 minutes Isolate BIT - 35.5 minutes establish normal charging and LD

Question 35

WHY are there time critical actions associated with an inadvertent SI

Answer 35

- Prevents the pressurizer from going water solid and putting water through the PORVs

Question 36

What will generate a RED path for FR-Z.1 (Response to High Containment Pressure)

Answer 36

- Containment pressure greater than 12#

Question 37

What will generate an ORANGE path for FR-Z.1 (Response to High Containment Pressure)

Answer 37

- Containment pressure greater than 2.8#

Question 38

What will generate an ORANGE path for FR-Z.2 (Response to Containment Flooding)

Answer 38

- Containment Water Level "Flood Level" status light LIT

Question 39

What color is generated to indicate a need to enter FR-Z.3 (Response to Containment Radiation Levels)

Answer 39

- YELLOW

Question 40

In ES-1.1 (SI Termination) if subcooling is lost what action is required

Answer 40

- Manually initiate ECCS flow as required AND transition to E-1

Question 41

While in ES-1.2 (Post LOCA Cooldown and Depressurization) what actions can be taken in the RNO if subcooling IS NOT met to remove CCPs/SI PPs

Answer 41

- IF RCS HL temperatures are less than 340 deg F (RHR entry condition), THEN verify one RHR pump running AND remove CCP/SI anyway - Basically, if you meet RHR entry conditions based on HL temperatures AND RHR is in service you can go ahead and remove the CCPs and SI PPs anyway since RHR will ensure subcooling

Question 42

While in ES-1.2 (Post LOCA Cooldown and Depressurization) if the RCS is saturated, why does the RCS cooldown come before the RCS depressurization

Answer 42

- To restore subcooled conditions so that the depressurization is effective - (Depressurizing under saturated conditions WILL NOT actually lower pressure, it will only cause inventory loss)