A method of promoting the transport of water through medium and coarse grained soils comprising the step of applying to the medium or coarse grained soil a soil amendment composition at a level of less than 20 parts per million parts by weight of dry soil, and preferably less than 5 ppm. The composition...http://www.google.es/patents/US4380886?utm_source=gb-gplus-sharePatente US4380886 - Method of promoting water transport through soil
