this study assessed if a permeable reactive barrier (prb) could be used to reduce sulphate and metal concentrations in hogarth pit lake, a sulphate-toxic (up to 2,000 mg/l) pit lake at the former steep rock iron mine in atikokan, ontario. both batch reactor and flow through reactor experiments were performed to simulate a prb at the bench-scale in order to assess the sulphate reducing capacity of different organic matter ... treatment 1 contained organic matter, creek sediment (sulphate reducing bacteria source), carbonate rock (acid neutralizing agent) and glacial till (non-reactive medium). treatments 2 and 3 were similar to treatment 1, except that treatment 2 did not include creek sediment and treatment 3 contained molasses as a nutrient.