40EP-9EO03 Loss of Coolant Accident (LOCA) Flashcards
What are the entry requirements for 40EP-9EO03 Loss of Coolant Accident (LOCA)
- LOCA has occurred (after SPTA’s)
- Direct entry Mode 3/4 LTOP not in-service
What is the Exit Criteria for 40EP-9EO03 Loss of Coolant Accident (LOCA)
- LOCA not confirmed
- SFSC’s not met
- LOCA EOP complete
- SFSC’s met
- SDC entry met/ break iso/ RCS in long term core cooling
What conditions cause Harsh Containment?
- 170°F
- 10▲8 mr/hr
For 40EP-9EO03 Loss of Coolant Accident (LOCA) what are the mitigating actions for an Unisolable leak?
- Rapid C/D with SGs (small leaks which require SGs for DHR)
- Long Term Core Cooling (simultaneous hot/cold leg inj.)
- SDC
How does a LBLOCA differ from a small break LOCA
- Press drops <200 psia and LPSI injects
- Heat removal via core boil-off and SI flow
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the Rx Control SFSC
- <2X10-4% ↔ or ↓
- All FSCEA inserted OR >40 gpm boration OR SDM verified
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the Maintenance of Vital Auxiliaries SFSC
- At least 1 PB
- At Least 1 same train as PB
- PKA, PKC, PNA
- PKB, PKD, PNB
- Bus Plus
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the RCS Inventory SFSC
Condition 1:
- Lpzr >10% [15%]
- ≥24°F [44] RCS subcooling
- RVUH ≥ 16%
Condition 2:
- SI flow adequate
- CET & RCS Subcooling <44°F and not ↑
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the RCS Press Control SFSC
Condition 1:
- W/in P/T limits
Condition 2:
- SI Flow Adequate
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the Core Heat Removal SFSC
- <44°F [60] superheat and not ↑
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the RCS Heat Removal SFSC
- 1 SG 45-60% NR feeding to 45-60% NR
- Tc ↔ or ↓
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the Containment Isolation SFSC
Condition 1:
- < 3 psig
- No CNTMT or secondary rad alarms or rise
Condition 2:
- CIAS Actuated
- No secondary rad alarm or rise
For 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the CTMT Temp/Press Control SFSC
Condition 1:
- <235°F (sat vapor temp for CSAS setpoint)
- <8.5 psig
- H2 < 1.1% (above min detectable)
Condition 2:
- 1 CS hdr > 4350 gpm
- <55 psig
- H2 <4.9%
During 40EP-9EO03 Loss of Coolant Accident (LOCA), What must be done with the CH L/U if a SIAS has actuated?
Why?
- Realign to RWT or SFP
- SFP for large leaks or CSAS
- maintains Seal Inj.
During 40EP-9EO03 Loss of Coolant Accident (LOCA), when would you be required to stop RCP’s?
- Press remains below SIAS - 1/loop
- Subcooling < 24°F [44] stop ALL
How long do you have to Stop RCP’s if below NPSH?
- 5 Minutes TCA
How long do you have to Isolate a letdown leak outside of CNTMT?
- 10 minute TCA
How long do you have to isolate a SI leak in one of the pump rooms?
- 30 Minutes TCA
How long do you have to isolate a RCP HPSC leak?
- 16.67 minutes TCA
During 40EP-9EO03 Loss of Coolant Accident (LOCA), how long do you have to place the H2 anal-izer in service?
- 30 minute TCA
- takes 30 minutes to get accurate readings
During 40EP-9EO03 Loss of Coolant Accident (LOCA), when would you stop BOTH CS pumps?
- Both pumps on mini-flow
- not expected to exceed 8.5 psig in 1 hour
During 40EP-9EO03 Loss of Coolant Accident (LOCA), what actions are required if CSAS has actuated?
- At least 1 header flow >4350 gpm
- Ensure ALL RCP’s are off
- Isolate RCP Seal BO
- Align H2 Recombiners
During 40EP-9EO03 Loss of Coolant Accident (LOCA), what is the criteria to stop ONE CS pump?
- Pcntmt <50 psig and not ↑
- SI actuated and sufficient flow
What is the concern with low CNTMT pressure during RAS?
- Low press could cause SI air binding due to entrained air from RAS sump
If one CS pump was stopped during 40EP-9EO03 Loss of Coolant Accident (LOCA) when would you be required to restart the second CS pump?
- Running CS pump trips
- Press cannot be maintained <55 psig
What would prevent you from restoring CNTMT cooling following a SIAS actuation?
- Water level in containment
Following a CSAS what are the required conditions to stop CS pumps?
- Stop 1 pump at a time
- Pcntmt <5 psig
- Not needed for iodine removal
- CTMT cooling restored OR SDC aligned OR not needed for H2 mixing
During 40EP-9EO03 Loss of Coolant Accident (LOCA), what condition would require a manual MSIS?
- CW flow to Main Condenser is lost
- Prevents over pressurizing condenser
- Isolates SGBD
How long do you have to Vent a SIT in a class battery charger is lost?
- 2 Hours
What is HPSI pump Throttle Criteria?
- ≥24°F [44] RCS subcooling
- > 10% [15] Lpzr ↔ or ↑
- 1 SG available 45-60% (being fed)
- RVUH ≥ 16%
What is RCS CDR limit and what actions are required if exceeded
- 100°F/hr
- Stop C/D
- Stabilize press/temp
- Continue C/D when within 100°F/hr
What are indications of RCS Voiding?
- LD flow > CH flow
- Lpzr ↑ significantly more than expected with spary operating
- RVLMS < 100%
- HJTC unheated indicates saturated conditions
What conditions indicate Natural Circulation?
- Loop ▲T <65°F
- Tc and Th ↔ or ↓
- ≥ 24 [44]°F subcooled via CET
- < 30°F ▲T B/W Th and max quadrant CET
What action is required if you cannot verify Natural Circulation?
- Ensure proper Feed flow/ Steam flow
How long does it take to develop Natural Circulation?
- 5-15 minutes
- Longer if tripped from lower power
What action will assist with reflux boiling?
- Maintain SGWL
During 40EP-9EO03 Loss of Coolant Accident (LOCA), what are the concerns when restarting RCP’s?
- RCP start criteria met
- Lpzr changes due to void collapse/ SG heat addition
- Wait 20 Minutes to ensure natural circ
- Reflux boiling causes slug of unborated water
What RWT levels would require securing CH pumps?
50, -4, 44
- 50% stop 1
- 46% stop 2
- 44% stop all 3
When does a RAS occur and What action is required?
- 9.4% RWT level
- Manually close RWT MOV’s
- 5 minute TCA
What are the minimum HPSI flowrates WHEN on sump recirc?
1 HPSI
- ≥ 250 gpm
2 HPSI
- ≥ 500 gpm
During 40EP-9EO03 Loss of Coolant Accident (LOCA), if 2 CS pumps are stopped due to a loss of suction on HPSI, what actions are required?
- Notify EC
- Go to FRP
What are the requirements for Hot Leg Injection?
2-3 hours after start of accident
Any of the following:
- <24°F [44] REP CET subcooling
- Lpzr < 10% [15]
- RVUH <16%
What is SDC entry criteria
- All SFSC’s met
- Ppzr < 385 psia
- Th < 335°F
- Lpzr > 30% [38] and controlled
- ≥ 24°F [44] RCS subcooling
- Activity will not cause unacceptable levels outside of CNTMT
What are the requirements for aligning CS for SDC?
- Ppzr < 210 psia
- RCS temp < 185°F