Q72 — EOP-FRHS-2 SG Overpressure Steam Release
W/E13 Steam Generator Overpressure-EK2.2 (3.0)
Given:
• The crew is performing 1-EOP-FRHS-2 (Response To Steam Generator Overpressure)
• 11 SG is 1150 psig
At time 12:00
• The crew is attempting to release steam from 11 SG
• 11MS18 (MS Warmup) and 11MS10 (Atmospheric Relief Valves) can NOT be opened
• RCS T-HOTs are 550 °F
In accordance with 1-EOP-FRHS-2, which ONE of the following completes the statements below?
At 12:00, the crew _(1)_ start the 13 AFW Pump in an effort to release steam from 11 SG.
If the crew is unable to release steam from 11 SG, then crew will _(2)_.
• The crew is performing 1-EOP-FRHS-2 (Response To Steam Generator Overpressure)
• 11 SG is 1150 psig
At time 12:00
• The crew is attempting to release steam from 11 SG
• 11MS18 (MS Warmup) and 11MS10 (Atmospheric Relief Valves) can NOT be opened
• RCS T-HOTs are 550 °F
In accordance with 1-EOP-FRHS-2, which ONE of the following completes the statements below?
At 12:00, the crew _(1)_ start the 13 AFW Pump in an effort to release steam from 11 SG.
If the crew is unable to release steam from 11 SG, then crew will _(2)_.
A. _(1)_ will _(2)_ cool down the RCS to < 540 °F using UNAFFECTED SGs
B. _(1)_ will _(2)_ establish AFW flow to 11 SG
C. _(1)_ will NOT _(2)_ cool down the RCS to < 540 °F using UNAFFECTED SGs
D. _(1)_ will NOT _(2)_ establish AFW flow to 11 SG
▶ Show Answer & Explanation
✓ A. Correct. For Part 1, IAW 1-EOP-FRHS-2 Step 5, lists the 13 AFW Pump as a permitted release path for the affected SG. Since the other permitted release paths are not available and 11 SG is a source of steam for the 13 AFW, the crew will start the 13 AFW Pump in an effort to release steam from 11 SG. For Part 2, IAW 1-EOP-FRHS-2 Step 9, if the crew is unable to release steam from 11 SG, then RCS T-HOTs will be maintained less than a maximum of 540 °F by using the unaffected SGs.
✗ B. Part 1 is correct. For Part 2, the candidate could incorrectly conclude that establishing cool AFW flow to 11 SG will help reduce 11 SG pressure.
✗ C. For Part 1, the candidate may incorrectly determine that the 11 SG is not a source of steam to the 13 AFW Pump. Consequently, the candidate would then incorrectly determine that the crew will not start the 13 AFW Pump in an effort to release steam from 11 SG. Part 2 is correct.
✗ D. For Part 1, the candidate may incorrectly determine that the 11 SG is not a source of steam to the 13 AFW Pump. Consequently, the candidate would then incorrectly determine that the crew will not start the 13 AFW Pump in an effort to release steam from 11 SG. For Part 2, the candidate could incorrectly conclude that establishing cool AFW flow to 11 SG will help reduce 11 SG pressure.
Ref: EOP-FRHS-2 (Response To Steam Generator Overpressure) | LO: NOS05FRHS00-02 (HEAT SINK FUNCTIONAL RESTORATION) | Source: New | Cognitive: Higher
Connections
- Related systems: AFW, Steam Generator & Blowdown, Main Steam
- Related EOPs: EOP-FRHS-2 — Response to Steam Generator Overpressure
- Related exam: 2018 NRC Written Exam