functionality of type f fly ash is inadequate for many of the above described purposes because it cannot sufficiently set gel or harden to desired compressive strengths at a rate rapid enough to accommodate industrial and municipal needs and requires excessive amounts of the relatively expensive agent portland cement accordingly for many land reclamation purposes and waste disposal purposes type f fly ash has proven to be highly undesirable if not altogether devoid of utility nevertheless it has been surprisingly discovered in attempts to obtain more cost effective reclamation that the use of type c fly ash having certain critically controlled calcium and aluminum compositions substantially enhances the filtration and adsorption of waste and pollutants from contiguous water without reversal from dispersion or washout this is particularly advantageous when reclaimed lands simultaneously function as ground water passages in the composition of the present invention it is preferred to pre mix the ash into an aqueous slurry containing from about 40 to 300 water by weight of ash the slurry can be pumped into ground water passages such as abandoned mine shafts excavation pits in production drilling wells waterway bottoms spillways etc where the ground water is known to contain undesirable levels of heavy metals.