Use of treated mine water for rainbow trout (Oncorhynchus mykiss) culture—a preliminary assessment

Abstract

Treated waters from active and abandoned coal mines are a potentially valuable, though underutilized resource, which may be used to expand the aquaculture industry in West Virginia and other mid-Appalachian states. A preliminary investigation of the technical feasibility of using treated acid mine waters to rear rainbow trout (Oncorhynchus mykiss) was conducted. In the study, a regimen of water quality monitoring was initiated to fully characterize a treated mine water and allow for comparison with requirements for salmonid culture. To complement water quality studies, a bioassay consisting of fifty rainbow trout were grown in a net pen in the treated mine water; production-scale studies were not the focus of this initial work. Although aqueous phase concentrations of metals associated with acid mine drainage (AMD) (Fe, Al, Mn, Ca, Mn) often exceeded limits recommended for salmonid culture, the fish grew and exhibited no physiological signs of stress. The lack of anticipated water quality impacts on the fish was attributed to a combination of the effects of high ionic strength on the chemical activity of dissolved metal species and the formation of dissolved metal–ligand pairs in the treated mine waters. Thus, non ideal effects of high ionic strength and the coordination chemistry of treated mine waters must be considered when assessing the suitability of such waters for aquaculture, as many water resources otherwise considered too impaired for aquaculture use may be rendered viable.