Q51 — LOCA-1 Feed Flow and SG Level Requirements
EPE: 009 Small Break LOCA-EK2.03 (3.0)
Given:
• A Reactor Trip and Safety Injection has occurred due to a Small Break LOCA on Unit 1
• The crew is controlling SG Levels in accordance with 1-EOP-LOCA-1 (Loss Of Reactor Coolant) Step 3.
• Containment Pressure is 2.5 psig and slowly rising
In accordance with 1-EOP-LOCA-1, which ONE of the following completes the statement below?
The crew is REQUIRED to maintain Total Feed Flow greater than 22E04 LB/HR until ___
• A Reactor Trip and Safety Injection has occurred due to a Small Break LOCA on Unit 1
• The crew is controlling SG Levels in accordance with 1-EOP-LOCA-1 (Loss Of Reactor Coolant) Step 3.
• Containment Pressure is 2.5 psig and slowly rising
In accordance with 1-EOP-LOCA-1, which ONE of the following completes the statement below?
The crew is REQUIRED to maintain Total Feed Flow greater than 22E04 LB/HR until ___
A. ALL SG NR Levels are greater than a MINIMUM of 9%
B. ALL SG NR Levels are greater than a MINIMUM of 15%
C. AT LEAST ONE SG NR Level is greater than a MINIMUM of 9%
D. AT LEAST ONE SG NR Level is greater than a MINIMUM of 15%
▶ Show Answer & Explanation
✓ C. Correct. Per 1-EOP-LOCA-1 Step 3, "MAINTAIN TOTAL FEED FLOW GREATER THAN 22E04 LB/HR LEVEL UNTIL AT LEAST ONE SG NR IS GREATER THAN 9% (15% ADVERSE)". Based on containment pressure, containment is NOT considered adverse. Consequently, the crew is REQUIRED to maintain Total Feed Flow greater than 22E04 LB/HR until AT LEAST ONE SG NR Level is greater than a MINIMUM of 9%.
✗ A. Incorrect but plausible. The candidate correctly determine containment as NOT adverse but then incorrectly conclude 1-EOP-LOCA-1 Step 3 requires Total Feed Flow greater than 22E04 LB/HR until ALL SG NR Levels are greater than the non-adverse limit of 9%.
✗ B. Incorrect but plausible. The candidate incorrectly determine containment as adverse and also incorrectly conclude 1-EOP-LOCA-1 Step 3 requires Total Feed Flow greater than 22E04 LB/HR until ALL SG NR Levels are greater than the MINIMUM adverse limit of 15%.
✗ D. Incorrect but plausible. The candidate incorrectly determine containment as adverse but then correctly recall that 1-EOP-LOCA-1 Step 3 requires Total Feed Flow greater than 22E04 LB/HR until AT LEAST ONE SG NR Level is greater than the MINIMUM adverse limit of 15%.
Ref: 1-EOP-LOCA-1 | LO: NOS05LOCA01-05 (LOSS OF REACTOR COOLANT AND LOSS OF COOLANT ACCIDENT ANALYSIS) | Source: New | Cognitive: Higher
Connections
- Related systems: AFW, Steam Generator & Blowdown
- Related EOPs: EOP-LOCA-1 — Loss of Reactor or Secondary Coolant
- Related exam: 2019 NRC Written Exam