Lysimeters for Simulating Sanitary Landfills

An interdisciplinary team is investigating the various decomposing processes inside sanitary landfills. Eight different ways of operation of sanitary landfills are simulated by special lysimeters. These lysimeters consist of flexible walls, which allow settlements similar to that of nature. Thermal insulation of the lysimeters protect the biological and chemical processes against outside temperatures. The leachate is collected separately from different compartments in the base, and samples of seepage are drawn from different levels. The lysimeters allow taking samples of refuse or the inserting of material at different places and levels. The density of the refuse in the lysimeter, filled according to today's practice, is in this range; while mixing of the refuse or refuse and sludge enlarges the density considerably. After aerobic decomposing, sieving and compacting the required deposition volume was one-third compared to the present common practice. It was shown, by five years of observation, that leachate occurs before the material was saturated. As a consequence thereof and by means of interpretation of the accumulated outflow of the lysimeter one can state that the quantity of outflow will increase after the operation of a sanitary landfill has ended.