"As part of the U.S. Environmental Protection Agency's (EPA) Scientific Activities Overseas program a contract was awarded to Poltegor, the Central Research and Design Institute for Openpit Mining, Wroclaw, Poland in 1974, to study vegetation stabilization of ash piles resulting from the burning of lignite and bituminous coal. Two ash piles were selected for study, i.e., ash from a lignite power plant and a bituminous plant. The first phases of the project included analyses of the ash, greenhouse studies of ash amendment and fertilizer treatments, field experiments evaluation of various treatment methods to improve the soil characteristics of the ash, and evaluation of various grasses, legumes, trees, and shrubs for planting on ash piles. These research results were published in an EPA publication in 1979, "Reclamation of Alkaline Ash Piles and Protection of Their Environment Against Dusting," EPA-600/ 7-79-128. Following these studies it was recommended that the project be continued to obtain long-term data on the survival and growth of the plants and to obtain information on the development of a food crop (barley) on ash piles where the ash had gone through a period of soil development. Major conclusions drawn from this study are: (1) The chemical and mineralogical composition and physics-chemical properties of ashes significantly affect classification of ashes regarding their soil formation ability; (2) The toxicity of the ashes to plants was caused by the high pH (9.0-12.8), salinity (up to 2%), boron (up to 50 ppm), sandy-clay composition, unbalanced chemical composition, and soil color (caused high temperatures); (3) The best yields of pioneer grasses and legumes were obtained from plots covered with 20 cm of soil; (4) Yields of grasses and legumes decreased 44-53% where fertilization of the plots stopped; (5) Yields of winter barley were dependent on the neutralization and fertilization treatment applied prior to introducing pioneer plants. The best results were obtained after applying fertile soil; and (6) Ash piles can be utilized for production of fodder and cereals after earlier neutralization and fertilization. The introduction of trees and shrubs does not appear to be practical because of the shallow layer of soil formed that limits deep root penetration."