Comparative effectiveness of mixed organic substrates to mushroom compost for treatment of mine drainage in passive bioreactors

► Bioreactors as sustainable technology for treating acid mine drainage. ► Different types of organic materials in mixture forms tested for bacterial growth. ► The mixtures gave satisfactory performance in sulfate reduction and metal removal. ► The mixture of saw dust and cow manure was most effective. ► Sulfate reduction depends on the type of DOC, not on the concentration of DOC.