EOP Week 5 & 6 Flashcards
Deck Covers: E-3, ES-3.1, ES-3.2, ES-3.3, ECA-3.1, ECA-3.2, ECA-3.3, CRE
While in E-3 (Steam Generator Tube Rupture), what is the purpose of the Major Action Category “TERMINATE SI”
- Stops the primary to secondary leakage
From E-3 (Steam Generator Tube Rupture), what transition is made if RWST level is less than 30%
- Per FOP go to ES-1.3 (Transfer to Cold Leg Recirculation)
From E-3 (Steam Generator Tube Rupture), what transition is made if a SINGLE Steam Generator PRESSURE is lowering in an uncontrolled manner OR is completely depressurized and WAS NOT previously isolated
- Per FOP go to E-2 (Faulted Steam Generator)
From E-3 (Steam Generator Tube Rupture), what transition is made if any intact SG level rises in an uncontrolled manner OR has abnormal radiation
- Per FOP stabilize the plant and go to E-3 (Steam Generator Tube Rupture) step 1
From E-3 (Steam Generator Tube Rupture), what transition is made following SI termination IF EITHER subcooling is less than 40 deg F OR Pzr Level CAN NOT be maintained greater than 16% {28% Adverse}
- Per FOP go to ECA-3.1 (SGTR with Loss of Reactor Coolant - Subcooled Recovery
In E-3 (Steam Generator Tube Rupture), when balancing SG and RCS level/pressure what is the preferred method of pressure control if L/D is AVAILABLE with NO RCPs
- Aux Spray
What is Iodine Partitioning
- With adequate SG levels (greater than 13%) Iodine concentrates in the SG while steaming minimizing the release.
How is SG overfill prevented in E-3 (Steam Generator Tube Rupture)
- Isolating the ruptured SG
- Cooldown and Depressurizing RCS
- Terminating SI
What are the consequences of SG Overfill during E-3 (Steam Generator Tube Rupture)
- Rupture of MS line from weight and water hammer
- Damage to SG PORVs
- Damage to SG Safeties
- Damage to TDAFP
While in E-3 (Steam Generator Tube Rupture), why is the SG PORV setpoint raised to 1040 psig on the RUPTURED SG
- Minimize release
- Maintains ruptured SG pressure greater than pressure in intact SG
In addition to Iodine Partitioning, why are SG levels maintained greater than 13% in the ruptured SG
- Keeps tubes covered which prevents steam from condensing on tubes and lowering SG pressure which would re-initiate/cause a rise in primary to secondary leakage
In E-3 (Ruptured Steam Generator) with NO RCPs running, why is the CL temperature indication for the loop containing the ruptured SG disregarded for CSFST monitoring
- With NO RCPs there is no flow in this loop
- ECCS is injecting in this loops and moving BACKWARDS through the SG past the CL RTD
- The vessel IS NOT subjected to this FALSE LOW CL temperature
- ONLY APPLICABLE WHILE IN E-3
When is a SG Tube Leak considered a SG Tube Rupture
- When the leak rate exceeds the capacity of one CCP with max flow AND L/D isolated
- Reactor trip AND SI required
What is the Tech Spec limit for Primary to Secondary Leakage
- 150 GPD (0.1 gpm)
What is the EPRI recommended limit for continued operation with Primary to Secondary Leakage
- 75 GPD
- SG’s not evaluated for leak before break
Per the SG tube leak AOP, what is the leakage threshold for initiating a Reactor Trip
- 50 gpm
Per the SG tube leak AOP, what is the leakage threshold for initiating a Reactor Trip AND SI
- 100 gpm
What is does the UFSAR assume regarding a SGTR
- Operator actions are taken to isolate the ruptured SG efficiently
What is the preferred method (Procedure) used to cooldown and depressurize the RCS following a SGTR
- ES-3.1 (Cooldown Using Backfill)
What are the ADVANTAGES of ES-3.1 (Post SGTR Cooldown using Backfill)
- Minimizes radiological releases
- Allows processing of water
What are the DISADVANTAGES of ES-3.1 (Post SGTR Cooldown using Backfill)
- Secondary chemistry effecst on RCS components
- Potential Boron dilution (could cause SR count to rise during cooldown)
- Slower than steaming
How is the ruptured SG LEVEL controlled during cooldown using ES-3.1 (Post SGTR Cooldown using backfill)
- RCS Pressure
- AFW
How is the SG metal temperature cooled when using ES-3.1 (Post SGTR Cooldown using Backfill)
- Allow SG level to lower to 20% (27%)
- SLOWLY refill to 62%
- SLOW to prevent rapid pressure drop that would reinitiate or raise leakage
What would happen if SG LEVEL was allowed to lower below 20% (27%) while in ES-3.1 (Post SGTR Cooldown using backfill)
- Tubes would become uncovered
- Causes depressurization of ruptured SG
- Reinitiates the leak
Why is Shutdown Margin verified during ES-3.1 (Post SGTR Cooldown using backfill)
- Dilution occurring from backfill
- No boration occurring since SI has been terminated
Why are RCP No. 1 seal dP and No. 1 Seal Leak off flow monitored during ES-3.1 (Post SGTR Cooldown using backfill)
- RCPs may need be stopped if these parameters get too low