Data part, material properties

start_arithmetic
pe 1.e-5 DIVIDE rho DIVIDE g_absolute
end_arithmetic

The saturated permeability is $10^{-5} \frac{\rm m}{\rm s}$. Look, however, at the definition of the permeability for the input file in the user's manual. A division by rho and g_absolute is needed; this is easily accomplished with start_arithmetic ... end_arithmetic, so that the input file remains readable.

group_type 1 -groundflow
group_porosity 1 0.5
group_groundflow_permeability 1 pe pe
group_groundflow_nonsaturated_vangenuchten 0 0.0 1. 2.49 -0.140 1.507

The group_type is set to -groundflow which means that the groundflow storage equation will solved in the elements. The porosity is set to $0.5$ with group_porosity. For the saturated permeability the pe as calculated in the start_arithmetic ... end_arithmetic is used. The group_groundflow_nonsaturated_vangenuchten records specifies the Van-Genuchten law for non-saturated groundwater properties.