Requesting help with a circuit design
In principle your truth table is correct. The 4th condition cannot be met straight away because it involves the use of memory, which should only be triggered at some specific point. 

I created a small simulation using a SR flip flop as memory, which is only triggered when the upper sensor is active (tank filled) and the tank begins to empty. I considered that the sensors are normally open, and conduct once the corresponding water level is reached.

The circuit emulates the water level with the aid of a voltage source ramping up to 1V and down to 0V. The top and bottom busses represent the sensors which are active above 90% and 10% of the total water level respectively.


The red waveform shows the motor driver, which is only enabled during the ramp up of the water, and not always when the condition T_TOP = 0 and T_BOTTOM = 1. The SR Flip Flop is activated and latched once the upper sensor is active, holding this state until the lower sensor is activated (turns off the latching mechanism).



Theoretically you could also use only the SR flip-flop as shown in the following picture, but you could run into a problem with the motor shortly turning on, even though the tank is full.



Keep in mind that I did not account for any forbidden conditions, so some additional check must be done.

I hope it helps.