Describe typical operator actions following a reactor scram in an NANTeL-equipped plant.

• A. Immediately restart the reactor
• B. Ignore alarms if they seem minor
• C. Delegate all actions to automated systems without operator involvement
• D. Confirm scram, monitor core conditions and reactor coolant system indicators, manage post-trip cooling, address alarms, and follow shutdown procedures while initiating post-trip analysis

Answer: (D)

After a reactor scram, the priority is to confirm the trip and secure cooling for decay heat while keeping plant conditions safe. Operators verify that the scram has occurred, then monitor core and reactor coolant system indicators (neutron flux decay, RCS pressure and temperature, coolant levels) to ensure rapid cooldown without recriticality. They establish and monitor post-trip cooling paths, address any alarms or abnormal indications, follow the prescribed shutdown procedures, and initiate post-trip analysis to review the event and verify stability. NANTeL supports the fast trip logic and alarms, but human action is needed to confirm the scram, interpret data, manage cooling, and complete the post-trip process. Restarting immediately would defeat the shutdown, ignoring alarms is unsafe, and leaving actions to automation alone neglects the necessary human-in-the-loop steps.