ABSTRACT

The ET landfill cover works with the forces of nature rather than attempting to control them. It utilizes a layer of soil covered by native grasses, and it contains no barrier layers (Figure 4.1). The ET cover uses two natural processes to control infiltration into the waste: (1) the soil provides a natural water reservoir and (2) natural evaporation from the soil and plant transpiration (ET) empties the soil water reservoir. At most sites, it is easy to build the ET cover to allow small or large percentages of annual precipitation to enter the waste. It is an inexpensive, practical, easily maintained, and self-renewing biological system. The ET cover will remain effective over extended time periods, perhaps centuries.