EOP Flashcards
What is adverse containment?
5 psig
10E5 R/hr
During ELAP Unit PRZ and SG temps verified below 196.8*F
If rad levels exceed 10E5 R/hr and eventually come back down, do you still have to use adverse containment values?
YES, until evaluated for integral dose
What is the order of priority of the Critical Safety Functions?
Subcriticality
Core Cooling
Heat Sink
Integrity
Containment
Inventory
Which CSFs require continuous monitoring?
Red or Orange
What are the fission product barriers?
Fuel Cladding
RCS (piping)
Containment
What are the methods of heat removal for a SBLOCA?
ECCS Flow / Breaker Flow
AFW / SGs
Why is a CL Break considered the worst scenario for a SBLOCA?
More mass is lost prior to ECCS flow equaling break flow. The cross under loop seal must be clear before steam can be vented from the break
What are indications of a faulted SG?
Tave lowers
Rx Power Rises
Possible turbine load lowering
SF > FF
What are indications of SGTR?
SJAE / GSLO Rad monitors high
SG Level rising uncontrollably
PRZ Pressure and Level Lowering
What are indications of a LOCA?
Containment Rad Monitor & Dew Point rising
PRZ Level and Pressure lowering
What is the SI Termination Criteria found in ES-1.1
Subcooling > 40*F
Heat Sink by SG level >13% OR > 240K ppm
RCS Pressure stable / rising
PRZ Level 16% (20%)
What does meeting your SI termination subcooling criteria tell you?
Adequate core cooling and secondary heat sink
What does meeting your heat sink SI termination criteria tell you?
Ensure subcooling will be maintained following termination
What does meeting your RCS Pressure SI Termination criteria tell you?
Ensures subcooling will be stable / rising and SI flow is effective in raising RCS Inventory
What does meeting your PRZ Level SI Termination Criteria tell you?
Sufficient RCS Inventory
Only valid if RC is subcooled
Ensures ability to maintain pressure following termination
Why do RCPs need to be tripped on a phase B?
Loss of CCW flow to RCP LO Coolers
Where do you transition from in E-0 if a Rx Trip is not successful?
FR-S.1
What is the order of diagnostic transitions in E-0 and why ?
E-2, easy to find/fix and can mask other issues
E-3, stops offsite dose. Lots of TCAs
E-1, auto actions can handle it
In E-0, why do we lower AFW to < 450K pph?
Limits overcooling the RCS
In E-0, why is the minimum AFW 240K pph until the minimum SG water level is maintained?
ENsures enough FW flow for decay heat removal. Also, min # for Heat Sink CSF Status Tree
What are the entry conditions for ES-0.0, Rediagnosis?
ALL of the following:
SI is I/S or Required
E-0 has been exited
E-Series procedure in progress
What must be done after a reactor trip for each control rod not fully inserted?
Borate 160 (150) ppm for each rod
If in ES-0.1, Reactor Trip Response, what do you do if you get an SI?
Return to Step 1 of E-0
Why would you transition from ES-0.2, Natural Circ Cooldown to ES-0.3, NC Cooldown w Steam Void?
If CST Inventory is low
After LOOP when a high rate of planned Cooldown and depressurization is required due to reduced CST inventory
What removes most of the heat from the head on NC?
CRDMs
In ES-0.3, Natural Circ Cooldown with Steam void, when should you not try to start an RCP?
If cooling had been previously lost
In ES-0.3, NC Cooldown w steam void, why is it required to raise PRZ Level to 84% prior to starting a RCP?
Ensures PRZ level doesn’t lower causing a loss of subcooling when the RCP is started due to void collapsing / lowering PRZ level
What are the benefits of restarting RCPs?
Enhances core heat removal
Improves RCS Pressure and Temp Control
Improves PRZ Level Control
Which RCP is the most effective?
3 bc it has the most dP
What are the 3 factors affecting spray flow?
Vessel and RCS piping DP
Coolant Velocity head at spray flow scoop located at spray flow penetration in CL
PRZ Level
What are the indications of NC?
Subcooling ? 40*F
Stable or Lowering:
- SG Pressures
- CETCs
- RCS HL Temps
RCS CL Temps at saturation temp for SG Pressure
What should be done if NC cannot be verified?
Raise steam dump flow
For a SBLOCA, why is 1300# trip criteria?
Ensures RCPs are stopped before the break is uncovered so no additional mass is lost
Why is CCW to RHR adjusted to 5,000 gpm during CL Recirc?
Prevents pump Runout if 1 pump fails
When is RHR Spray placed in service?
50 mins (allows decay heat removal) - 70 mins (containment peak pressure)
What are the 10CFR100 Limits at the site boundary?
25 REM Whole Body, 300 REM Thyroid for 2 hours
For a Faulted SG, when will you have a SI?
Upstream of the MSIVs for a steam break or downstream of check valve for a feed break.
In E-2, faulted SG Isolation, why will AFW have to be periodically reduced to maintain SG Levels after RCS Temp is stabilized?
Lowering Decay Heat Levels
In E-2, Faulted SG Isolation, why do we control AFW Flow?
Prevent SG Dryout
Minimize RCS Cooldown
Prevent SG Overfill
Control RCS Temp after Cooldown is stopped
During E-3, SGTR, why do we want to terminate SI?
Helps control primary to secondary leakage
What could be a potential problem if the SG is overfilled during a SGTR?
Rupture of MS Line from weight of the water
Damage to PORVs, Safeties and TDAFP
During a SGTR, what is the affected SG PORV set point changed to and why?
1040 psig to minimize the release
Why do we ensure the ruptured SG level reaches 13% before isolated AFW to it?
To ensure SG Tubes are covered, which will prevent depressurization
What does the UFSAR assume for a SGTR?
Operator actions are taken to isolate ruptured SG efficiently
What are the advantages and disadvantages of ES-3.1, Cooldown using backfill?
+ Minimizes radiological releases and allows processing of RCS
- Potential boring dilution, secondary chemistry effects on RCS, Slow
What are the advantages and disadvantages of using ES-3.2, Cooldown using blowdown?
+ Minimizes radiological releases, NO boron dilutions or chemistry effects
- storage / processing capabilities, spreads contamination, SLOW
What are the advantages / disadvantages of using ES-3.3, cooldown using steam dump method?
+ FAST
- Contamination / radiation, potential water hammer on secondary components.
When would you transition back to E-2 from ECA-2.1, Uncontrolled depressurization of all SGs?
If any SG pressure boundary is restored, except while performing SI Term steps 10-20
During ECA-2.1, what is AFW lowered to and why?
25K per SG to prevent boiling dry and minimize thermal shock effects if FF is later raised
What is the minimum DP that should be maintained between the ruptured and intact SGs?
250#
When would you enter ECA-3.1, SGTR w loss of RC, subcooled recovery?
Cannot isolate ruptured SG from any intact SGs
Faulted and Ruptured SG
Min DP cannot be maintained
SGTR w LOCA