Abstract: The present invention is directed to a method of trans-seasonal bioremedial treating of mine-influenced water and soil (MIWAS) in situ with microorganisms for removal of contaminants containing heavy metals compounds. The method comprises the steps of: a) sampling indigenous microorganisms from the MIWAS site being treated; b) identifying and/or isolating indigenous microorganisms that consume selected compounds to be treated in the MIWAS; c) propagating at least one of the indigenous microorganisms identified or isolated in step b); and d) reintroducing propagated microorganisms either on the soil surface or subsurface at the MIWAS site together with a source of nutrients and a carbon source for the microorganisms; wherein when the microorganisms, nutrients, and carbon source are reintroduced on the soil surface, they are subsequently buried.