Nairn, R.W., and T. Wall | 2019 West Virginia Mine Drainage Task Force Symposium, 26-27 March, Morgantown, WV, 49 slides, 2019

A sulfide removal approach using a custom-designed solar-driven system with activated carbon filter (ACF) was evaluated at the Southeast Commerce passive treatment system (SECPTS) at the Tar Creek Superfund site. SECPTS addresses 380 L/min of net alkaline mine waters using an oxidation pond, surface flow wetland, vertical flow bioreactors (VFBRs), and final polishing unit (FPU). VFBR effluent enters a closed odor-control structure (OCS) from which the sulfide-rich atmosphere is pulled into the ACF using a solar-powered vacuum blower. Solar-powered pressure blowers reaerate the water column through float-mix aerators in the post-VFBR FPU. Aqueous sulfide concentrations were determined by laboratory analyses of surface water grab samples, and gaseous sulfide concentrations were field-measured using a handheld gas detector and Draeger hydrogen sulfide gas detection tubes. Throughout the sampling period (December 2017-October 2018) the maximum aqueous sulfide concentration in the VFBR effluent was 84 mg/L, and the maximum gaseous sulfide concentration in the OCS atmosphere was 950 parts per million by volume (ppmv). FPU effluent aqueous sulfide concentrations measured 0.13-0.28 mg/L. ACF exhaust gaseous sulfide concentrations measured 41-56 ppmv. Over the study period, approximately 14,000 kg S were retained by SECPTS, presumably by bacterial sulfate reduction in the VFBR. Additionally, 100 kg gaseous S entered the ACF with 30 kg retained in the ACF media, 20 kg exhausted to the atmosphere, and 40 kg leaving the ACF as sulfuric acid. Evaluation of the systems indicates they enhanced water quality improvement effectiveness, efficiently removed gaseous sulfide, and may be used in remote locations and at sites where operation and maintenance budgets are limited. https://wvmdtaskforce.files.wordpress.com/2019/03/2019-1030-nairn-_wvmdtfs_03272019.pdf