Six overburdens from a potential lignite mining area of Louisiana were used to evaluate their weathering as affected by a combination of rates of fertilizer, lime, plant growth and simulated well drained conditions. Subterranean clover (Trifolium subterranean) grown on each overburden material in plastic pots received O, lx, 2x, 4x and 8x the recommended rate of fertilizer which was a combination of P and K. Lime was applied to the overburdens based on soil test lime requirement to increase the pH to 6.5.