A vegetation experiment was carried out with different amounts of vermiculite mixed with humus depot substrates, tailings pond and mine, in different proportions, and with an application of mineral fertilization and liming. Biomass carbon of microbial origin has the highest values after the addition of 10% vermiculite, simultaneous application of fertilization and liming, and alone fertilization, compared to controls, without ameliorants. The activity of the studied enzymes - cellulase, amylase, invertase and catalase increased with increasing concentration of vermiculite, as well as in the combined application of fertilization and liming. The values of microbial biomass carbon and enzymes are highest in the variants with substrates from the mine.