JPM Sim-c — Isolate ECCS Accumulators in EOP-LOCA-1
Sim | RO/SRO | 006 A3.10 (4.0/3.9)
Location: Simulator
Time-Critical: No
Alternate Path: Yes
Estimated Time: 8 minutes
Initial Conditions:
- The reactor was tripped when a RCS leak occurred.
- The operating crew has progressed through the EOPs and is now in 2-EOP-LOCA-1, LOSS OF REACTOR OR SECONDARY COOLANT.
Initiating Cue:
- You are the Reactor Operator.
- The CRS directs you to isolate the SI Accumulators IAW Step 14 of 2-EOP-LOCA-1, LOSS OF REACTOR OR SECONDARY COOLANT.
- Notify the CRS when Step 14 is completed.
- Your evaluator will take care of all alarms not related to your task.
Time-Critical: No
Alternate Path: Yes
Estimated Time: 8 minutes
Initial Conditions:
- The reactor was tripped when a RCS leak occurred.
- The operating crew has progressed through the EOPs and is now in 2-EOP-LOCA-1, LOSS OF REACTOR OR SECONDARY COOLANT.
Initiating Cue:
- You are the Reactor Operator.
- The CRS directs you to isolate the SI Accumulators IAW Step 14 of 2-EOP-LOCA-1, LOSS OF REACTOR OR SECONDARY COOLANT.
- Notify the CRS when Step 14 is completed.
- Your evaluator will take care of all alarms not related to your task.
Task Standard:
1. Closes 21, 22, and 23 SJ54s. 2. Vents 24 SI Accumulator to atmospheric pressure.
1. Closes 21, 22, and 23 SJ54s. 2. Vents 24 SI Accumulator to atmospheric pressure.
▶ Show Critical Steps & Key Actions
| Step | Critical Element | Standard |
|---|---|---|
| 14 | Are at least two RCS T-Hots less than 405F | YES. Operator verifies at least two RCS T-Hots less than 405F. |
| 14.1 * | Remove lockout from 21-24 SJ54 (Accumulator Outlet Valves) | At 2RP4 Panel, selects VALVE OPERABLE on 21-24 SJ54 Accumulator Outlet Valves Lockout Switch. |
| 14.1 (contd) * | CLOSE 21 thru 24 SJ54 | Depresses CLOSE pushbuttons for 21 thru 24 SJ54 Accumulator Outlet Valves and verifies each CLOSE bezel illuminates. |
| 14.2 | Are 21 thru 24 SJ54 CLOSED | NO. Operator determines 24SJ54 Accumulator Outlet Valve is OPEN. May re-check lockout switch position or attempt to depress Close PB again. |
| 14.2 (contd) * | Vent unisolated accumulator: OPEN 2NT35 (N2 HDR Valve) and 24SJ93 (N2 Supply Valve) | Depresses OPEN PB for 2NT35 (N2 HDR Valve) until OPEN bezel illuminates. Depresses OPEN PB for 24SJ93 (N2 Supply Valve) until OPEN bezel illuminates. Observes 24 Accumulator pressure lowering to ZERO. |
Key Decision Point:
Step 14.2 is the alternate path / discriminating step. After closing 21-23 SJ54, the applicant discovers that 24SJ54 fails to close (valve stuck open). Rather than continuing to attempt closure, the applicant must recognize that the accumulator cannot be isolated normally and must vent the 24 Accumulator to atmospheric pressure by opening 2NT35 (N2 Header Valve) and 24SJ93 (N2 Supply Valve), then verify accumulator pressure reaches zero.
Step 14.2 is the alternate path / discriminating step. After closing 21-23 SJ54, the applicant discovers that 24SJ54 fails to close (valve stuck open). Rather than continuing to attempt closure, the applicant must recognize that the accumulator cannot be isolated normally and must vent the 24 Accumulator to atmospheric pressure by opening 2NT35 (N2 Header Valve) and 24SJ93 (N2 Supply Valve), then verify accumulator pressure reaches zero.
Ref: 2-EOP-LOCA-1 (Rev 40) | Task: N0060100101 | K/A: 006 A3.10 — Ability to monitor automatic operations of the ECCS (4.0/3.9) | Safety Fn: 3 | Source: Bank | View JPM PDF
Connections
- Related procedures: EOP-LOCA-1 — Loss of Reactor or Secondary Coolant
- Related systems: ECCS
- Related exam: 2022 NRC Operating Exam