Data part, boundary conditions on edges

bounda_dof 0 -right_wet_edge -pres
bounda_time 0 -200.0
bounda_dof 1 -left_edge -total_pressure
bounda_time 1 0.0

The bounda_dof records are used to prescribe conditions for the water pressures. On the part of the right edge below the water level a hydraulic head $h$ of $-200.0$ is prescribed (the word -pres means hydraulic head). You can understand that is OK, by looking at the equation for the total pressure (pore pressure)

$$p_{\rm total} = h - \rho g y$$

With density $\rho = 1.0$, gravity $g = -10.0$ we find at $y=0.0$ that the pore pressure is $-200.0$, and at $y=20.0$ that the pore pressure is $0.0$.

On the total left edge we prescribe a zero pore pressure.

On the bottom edge we don't allow for any groundflow flux. In Tochnog a zero normal flux is imposed automatically if you don't specify anything, thus you don't see conditions at the bottom edge in the bounda_* records.