Correction to "Steady-state saturated groundwater flow modeling with full tensor conductivities using finite differences"

We present a new three-dimensional steady-state saturated groundwater-flow forward-simulator with full conductivity tensors using a nineteen-points block-centered finite-difference method. Hydraulic conductivity tensors are defined at the block interfaces eliminating the need to average conductivity tensors at adjacent blocks to approximate their values at the interfaces. The capabilities of the code are demonstrated in three heterogeneous formulations, two of the examples are two-dimensional, and the third one is three-dimensional and uses a nonuniform discretization grid. A benchmark, in the context of conductivity upscaling, is carried out with the MODFLOW LVDA module, which uses hydraulic conductivity tensors at block centers and then approximates their values at the interfaces. The results show that our code gives more accurate predictions for the interblock fluxes than the MODFLOW LVDA module when the block conductivity principal directions are not parallel to the Cartesian axis.