Use of “The Capillary Barrier” as a Shield against Groundwater Pollution from Fly-Ash Deposits

The enormous amounts of fly-ash produced by the burning of coal in power plants have resulted in a number of environmental problems, not least of which is the increased risk of groundwater pollution from its deposition in gravel pits. In order to prevent this pollution, fly-ash deposits have often been established with an underlying membrane. Such membrane-systems are quite expensive to build and necessitate besides a continous pumping and removal of percolate. The alternative of covering the fly-ash with a low-permeable membrane, which removes the infiltrated water laterally, prevents not only groundwater pollution but also the formation of percolate. By using the principle of “The Capillary Barrier”, the lowpermeable membrane can be constructed of natural and resistant porous materials.