Use of Biochar Amendments for Removing Bacteria from Simulated Tile-Drainage Waters.

The addition of biochar has been shown to increase bacterial removal rates by several orders of magnitude in sand-packed columns, suggesting that biochar may be a suitable amendment for use in end-of-tile filter systems to remove indicator and pathogenic microorganisms in tile -drainage waters. Additional research, however, is needed to determine the best combination of biochar and porous media characteristics for maximizing bacterial removal from drainage waters. Research was conducted to determine whether biochar-amended sand filters are an effective management strategy for removing pathogenic and indicator microorganisms from tile-drainage waters. Experiments using a commercially-available biochar (Biochar NOW) were conducted at application rates of 15 and 30 % (by volume). Two sand sizes (0.8 and 1.3 mm) were also investigated. Results indicate that the addition of Biochar NOW greatly reduces the transport of E. coli and Salmonella through laboratory-scale biofilters. The rate of removal of bacteria was shown to be a function of biochar concentration, flow rate, composition of carrier solution, and total bacterial loading.