2018 Q28 — CVCS Phase A Containment Isolation

✓ B. Correct. For Part 1, 1CV284 & 1CV116 (RCP SW RET HOR STOP VALVES) will close. This causes seal return flow to be redirected from the VCT to the PRT via Relief Valve 1CV15. For Part 2, letdown will be isolated during a Phase A isolation. This is accomplished by closing 1CV5 and 1CV7.

✗ A. Incorrect but plausible. Part 1 is correct. For Part 2, 1CV2 and 1CV277 will automatically close on low PZR level. Consequently, the candidate could incorrectly conclude that 1CV2 and 1CV277 also automatically close on a Phase A Containment Isolation.

✗ C. Incorrect but plausible. For Part 1, seal injection flow is normally directed to the VCT. The candidate could incorrectly conclude that redirecting seal injection to the PRT is not desirable since this will cause a loss of RCS inventory. For Part 2, 1CV2 and 1CV277 will automatically close on low PZR level. Consequently, the candidate could incorrectly conclude that 1CV2 and 1CV277 also automatically close on a Phase A Containment Isolation.

✗ D. Incorrect but plausible. For Part 1, seal injection flow is normally directed to the VCT. The candidate could incorrectly conclude that redirecting seal injection to the PRT is not desirable since this will cause a loss of RCS inventory. Part 2 is correct.

Ref: NOS05CVCS00-17 (CHEMICAL AND VOLUME CONTROL SYSTEM) | LO: 9 — State the setpoints for automatic actuations associated with the Chemical and Volume Control System | Source: Modified Bank | Cognitive: Higher