2020 Q16 — LOCA Outside Containment Indication

✓ A. Correct. After performing individual flowpath isolations in 2-EOP-LOCA-6, LOCA Outside Containment, the question; "Is RCS Pressure Rising" is asked. The procedure basis states; "If the break is isolated in EOP steps ..., a significant RCS pressure increase will occur due to the ECCS flow filling up the RCS with break flow stopped."

✗ B. Plausible because if break flow has been successfully terminated, then RCS inventory should increase resulting in rising PZR Level. Also plausible because a number of EOPs check PZR Level when checking if SI can be terminated. Incorrect because LOCA-6 specifically asks if RCS Pressure is rising.

✗ C. Plausible because if break flow has been successfully terminated, then RCS inventory should increase resulting in rising RVLIS Level. The procedure basis even states that if the RCS is saturated or a cooldown is in progress, RCS re-pressurization will proceed more slowly and other means of verifying break isolation should be checked like an increasing RVLIS trend. Incorrect because LOCA-6 specifically asks if RCS Pressure is rising. Also incorrect because dynamic range RVLIS would not be valid during a small break LOCA as the RCPs would have been stopped IAW CAS at < 1350 psig.

✗ D. Plausible because if break flow has been successfully terminated, then RCS pressure should increase and subsequently RCS subcooling will rise as well. Again plausible because RCS subcooling > 0°F is used throughout the EOP network to check if SI can be terminated. Incorrect because LOCA-6 specifically asks if RCS Pressure is rising.

Ref: 2EOP-LOCA-6, LOCA Outside Containment and Bases | LO: NOS05LOCA06-03, ELO 5 | Source: Modified Bank - Salem Vision Database | Cognitive: Fundamental