Q18 — LOCA Outside Containment / SJ49 Valves
WE04 EA1.1 (4.0)
Given:
• A LOCA Outside Containment has occurred on Unit 2.
• The crew is performing actions to isolate the leak in accordance with 2-EOP-LOCA-6, LOCA Outside Containment.
In accordance with 2-EOP-LOCA-6, which ONE of the following completes both statements?
1. In order to operate the SJ49s, Cold Leg Isolation Valves, what action(s) MUST be performed?
2. Following valve closure, what parameter is monitored to determine if leak isolation was successful?
• A LOCA Outside Containment has occurred on Unit 2.
• The crew is performing actions to isolate the leak in accordance with 2-EOP-LOCA-6, LOCA Outside Containment.
In accordance with 2-EOP-LOCA-6, which ONE of the following completes both statements?
1. In order to operate the SJ49s, Cold Leg Isolation Valves, what action(s) MUST be performed?
2. Following valve closure, what parameter is monitored to determine if leak isolation was successful?
A. 1) Reset Phase A AND place the affected SJ49 CMC switch in VALVE OPERABLE.
2) RCS Pressure
2) RCS Pressure
B. 1) Reset Phase A AND place the affected SJ49 CMC switch in VALVE OPERABLE.
2) PZR Level
2) PZR Level
C. 1) Place the affected SJ49 CMC switch in VALVE OPERABLE ONLY.
2) PZR Level
2) PZR Level
D. 1) Place the affected SJ49 CMC switch in VALVE OPERABLE ONLY.
2) RCS Pressure
2) RCS Pressure
▶ Show Answer & Explanation
✓ D. Correct. To close the SJ49's, only the CMC switch on 2RP4 needs to be placed in Valve Operable. SJ49s are normally open and are not closed by an SI signal or a Phase A signal. IAW 2-EOP-LOCA-6, when each valve is closed, the operator monitors RCS pressure rise to determine if the leak is isolated.
✗ A. Incorrect. First part is incorrect. To close the SJ49's, only the CMC switch on 2RP4 needs to be placed in Valve Operable. SJ49s are not closed by an SI signal. Second part is correct. Plausible because the operator may incorrectly believe that these valves are Phase A valves.
✗ B. Incorrect. First part is incorrect. To close the SJ49's, only the CMC switch on 2RP4 needs to be placed in Valve Operable. SJ49s are not closed by an SI signal. Second part is incorrect. RCS pressure is monitored to determine if leak is isolated. Plausible because the operator may incorrectly believe that these valves are Phase A valves.
✗ C. Incorrect. First part is correct. Second part is incorrect. RCS pressure is monitored to determine if leak is isolated. Plausible because PZR level is an indication that may change when the leak is isolation, but it's not the parameter used in the EOP.
Ref: 2-EOP-LOCA-6, Rev. 40 | LO: NOS05ALOCA06, Obj 5 — Determine the indications that are monitored to ensure proper system/component operation for each step in the EOP for LOCA OUTSIDE CONTAINMENT RECIRCULATION | Source: New | Cognitive: Fundamental/Memory
Connections
- Related systems: RHR, ECCS
- Related EOPs: EOP-LOCA-6 — LOCA Outside Containment
- Related exam: 2022 NRC Written Exam