Free drainage lysimeters containing a soil monolith are widely accepted tools to study the environmental behavior of pesticides in accordance with good agricultural practice. At the lower boundary a local saturation is necessary to collect the leachate. This artifact results in differences of the water balance and solute transport between field and lysimeter. To minimize these differences a new lysimeter facility equipped with a cellar was built, where large size round lysimeters (2 m2 surface, 2.5 m depth) are constantly weighed and the soil layers monitored for various soil parameters. Our large size lysimeters have a defined seepage face, which is adjusted by a vacuum applied to a stainless steel porous bottom plate. The design of the lysimeter box and the careful filling procedure avoid cracks, soil compression and drainage along the lysimeter wall. The bottom plate will be pressed with help of a slide. Soil areas showing preferential flow will be identified by a leachate collection drain divided in eight sections. The modular construction of the lysimeter facility allows the use of radioisotopes for experiments with an environmental focus as well as the application of non-invasive techniques.