Safety Analysis (Drey) Flashcards
The PVGS safety limit for DNBR is ___?
A. < 1.24
B. > 1.24
C. < 1.34
D. > 1.34
D. > 1.34
Which one of the following would be considered a Single Failure in our Accident Analysis?
A. A RCS Pipe Rupture
B. A Failure of Two Diesels to Start
C. A dropped or slipped single CEA
D. A Turbine Trip with a Loss Of Offsite Power
D. A Turbine Trip with a Loss Of Offsite Power
A ______________ is the event or events in a category of events that would require LCOs, procedures, plant design, etc. to minimize the consequences to the health and safety of nuclear workers and the public.
A. design fault
B. limiting fault
C. limiting event
D. design accident
C. limiting event
When describing an ATWS event, which of the following is a ‘transient of greatest concern’ ?
A. Small break LOCA
B. ESD inside containment
C. Dropped or Slipped CEA
D. Loss of Normal Electrical Power
D. Loss of Normal Electrical Power
Which of the following systems is designed to protect the plant in the event of an ATWS?
A. RPS
B. AFAS
C. SBCS
D. DAFAS
D. DAFAS
Given the following conditions:
• Unit 1 is at 100% power when a loss of offsite power occurs (LOOP).
• Both DGs fail to start.
Which of the following describes how the safety analysis assumes the reactivity control safety function is maintained?
A. Plant cooldown is limited to 75°/hr.
B. The plant is maintained in hot standby.
C. Within 1 hour RCS pressure is reduced below SIT pressure.
D. After verification of all CEAs inserted, the plant will be rapidly cooled to SDC entry conditions.
B. The plant is maintained in hot standby.
What is the purpose of RCP coastdown following a turbine trip with a LOOP?
A. Prevents RCP damage.
B. Helps establish natural circulation.
C. Prevents potential voltage spike from disabling vital buses.
D. Provides for maximum decay heat removal immediately following the trip.
D. Provides for maximum decay heat removal immediately following the trip.
For which of the following accidents does our Chapter 15 analysis assume a concurrent loss of offsite power (LOOP)?
A. RCS dilution.
B. Seized RCP Rotor.
C. Uncontrolled CEA withdrawal at power.
D. Steam Generator Tube Rupture (SGTR).
D. Steam Generator Tube Rupture (SGTR).
The UFSAR assumes that the release to the atmosphere following the limiting SGTR is terminated _______ hours after the event.
A. 1
B. 4
C. 8
D. 24
C. 8
Given the following conditions:
- Unit 1 was operating at 100% power when the Reactor trips on low Pressurizer pressure.
- A SIAS and CIAS automatically initiated.
- A Loss of Offsite Power occurred when the Main Turbine tripped.
After completion of SPTA the following conditions exist:
- Reactor Power is lowering.
- Pressurizer level 13% and slowly lowering.
- Pressurizer Pressure is 1810 psia and stable.
- Subcooling is 40ºF and slowly degrading.
- S/G pressures are 1180 psia and slowly rising.
- TC is 565ºF and slowly rising.
- Feed flow to both Steam Generators are equal at 500 gpm.
- Steam Generator ‘1’ level is 10% NR and slowly rising.
- Steam Generator ‘2’ level is 30% NR and rising rapidly.
Based on the given indications what Time Critical Operator Action is credited in 40DP-9ZZ04, Time Critical Action Program?
A. Both Steam Generator tubes are covered within 46 minutes.
B. Any release is terminated after 16 hours when MODE 5 is achieved.
C. Within 70 minutes affected Steam Generator isolated (Hot leg target temperature reached).
D. After 21.5 minutes a RCS cooldown is performed with only Steam Generator 1 ADVs at approximately 100ºF/hr to TH = 540ºF.
C. Within 70 minutes affected Steam Generator isolated (Hot leg target temperature reached).
The UFSAR analysis for a SGTR at Palo Verde assumes that the failures for the SGTR includes a loss of offsite power and the added single failure of . . .
A. RCS iodine spike.
B. of a Main Steam Safety Valve open.
C. a stuck open ADV on the affected SG.
D. an Auxiliary Spray Valve to operate with the other out of service for maintenance.
C. a stuck open ADV on the affected SG.
During a Loss of Main Condenser Vacuum event, the safety analysis assumes the plant is shutdown by the…
A. VOPT trip.
B. low SG level trip.
C. high SG pressure trip.
D. high PZR pressure trip.
D. high PZR pressure trip.
All assumptions in the UFSAR analysis for Decrease in Heat Removal are aimed toward…
A. minimizing DNBR.
B. maximizing RCS pressure.
C. maximizing linear heat rate.
D. maximizing reactor power peaking.
B. maximizing RCS pressure.
What is the most limiting event with regards to Decrease in Heat Removal TAA.
A. Loss of all Feed
B. Main Turbine Trip
C. RCS and SG heat up
D. Loss of Condenser Vacuum
D. Loss of Condenser Vacuum
Per the Technical Specifications bases for LCO 3.7.5, Auxiliary Feedwater (AFW) System, what are the limiting Design Basis Accidents (DBAs) and transients for the AFW System?
- Large Break LOCA
- Feedwater Line Break
- Main Steam Line Break
A. 1 ONLY
B. 2 ONLY
C. 1 and 3 ONLY
D. 2 and 3 ONLY
D. 2 and 3 ONLY