A vegetative cover is a remedial technique utilized on coal FA landfills for soil stabilization and for the physical and chemical immobilization of contaminants. Many herbaceous plants, primarily grasses which exhibit rapid growth, are moderately resistant to environmental stress, and are therefore often used as cover crops in environmental restoration and remediation projects. However, there is a great concern, that plants planted or voluntarily growing on media with high content of FA may absorb toxic amounts of Se and/or heavy metals. If such plants are ingested, it may result in toxicity to animals and humans. Despite these objections, the utilization of FA as a growth medium for plants is an attractive alternative for disposal of FA in landfills. We hypothesized that selected plants will grow in media containing FA and/or bottom ash (BA) from several sources. Therefore, the objective of this experiment was to determine the effects of growth media containing FA and/or BA on several cereal crop plants growth including germination, seedlings growth and heavy metals, B and Se accumulation in the seedlings. Two selected coal FA, from Montana semi-bituminous coal and from North Dakota lignite alone or in combination with BA from Montana semi-bituminous coal have been tested as plant growth media (growth media are listed in Table below) for the following plant species: barley ( Hordeum vulgare), oats ( Avena sativa), rye ( Secale cereale), wheat ( Triticum aestivum), regreen; a hybrid between wheatgrass ( Agropyron cristatum) and winter wheat ( Triticum aestivum), and triticale; a hybrid between wheat ( Triticum aestivum) and rye ( Secale cereale). The concentrations of Al, As, B, Ba, Be, Co, Cd, Cr, Cu, Mo, Pb, Sr, Ti, Tl, and V in growth media was determined, and the concentrations of the same elements in young plants was analyzed. Chemical analysis was performed using inductively coupled plasma (ICP) emission spectrophotometry (3). The data were analyzed statistically using ANOVA and Statistical Analysis System. All plant species tested in our experiments showed significant adaptability to the growth on FA based media, with no excessive accumulation of tested elements in plant seedlings. There were noticeable differences in seedlings growth, depending on the type and source of coal ash used. It suggests the necessity to perform pre-plantation tests in case of planning to provide green cover over FA piles. Large scale implementation of plant cover over coal ash landfills will require to conduct in-depth and large scale research.
