During normal operation the hot/cold water interface level in the Lower Density Lock is maintained constant by varying the speed of the Primary Pumps.

Any rising of the interface level is counteracted by an increase of the pump motor speed. Any lowering of the interface level is counteracted by slowing down the pump speed.

Dynamic Analysis of ISIS Control System is in progress. Preliminary results, not yet published, confirm that the reactor power is controlled by the concentration of boron in the primary water and by the intrinsic negative feedback of the core.