While acid mine drainage is a significant problem in the Appalachian mining region, some sites maintain near-neutral to alkaline conditions, resulting in significantly different water quality concerns, such as high salt, sulfate and Mn concentrations.  Runoff from Guy Cove, a surface mined site in southeastern Kentucky, has average sulfate and Mn concentrations of 1300 and 30 mg/L, respectively, and EC of 1,930 μS.  As part of the stream restoration associated with mine reclamation, this research focused on the removal of Mn from solution by funneling the runoff from the site through a bio-reactor that enhances sulfate reduction to sulfide. The conversion of Mn-sulfate to Mn-sulfide forms, which are much less soluble, is expected to result in near-permanent immobilization of significant amounts of Mn and a portion of the sulfates within the substrate. The bio-reactor consisted of a waste organic carbon source and a limestone gravel substrate designed to sustain reducing conditions.  Four different organic carbon sources in combination with four different mineral substrates to form the sorption substrate were used, including soybean oil, distillery waste, manure/mulch, and biosolids.  River gravel, sand, creek sediment, and limestone chips represented the mineral portion of the substrate.   Preliminary results indicate a widely variant potential among the organic carbon materials to remove Mn from solution, ranging from 35% reduction for soybean oil to 97% for the mulch mixture over a three week period, with respective Eh ranges of +60 mV and -320 mV. The mulch mixture has a high buffering capacity, maintaining pH higher than 8.0, while maintaining a low Eh (< -300 mV).  However, sulfate reduction levels were not stoichiometrically matched with those of Mn, suggesting the involvement of additional removal mechanisms.