By Summer Orledge

Faculty Mentor: Dr. Tyler Frankel

Abstract

Industrial coal combustion residuals (CCRs) are rich in trace metals that infiltrate surface waters via accidental spills, authorized discharges, and leaching from lined or unlined impoundments. Several of these have been shown to act as neurotoxins, hepatotoxins, and/or carcinogens in a variety of vertebrate species. Existing research has primarily focused on the impacts of major catastrophic release events. Thus, this study aimed to evaluate the spatial distribution and biological impacts of trace metal contaminants near the Bremo Power Station (New Canton, VA) which maintains 6.2 million yd³ of CCRs in its proximal unlined North Ash Pond adjacent to the James River. Surficial sediments and adult panhandle pebblesnails (Somatogyrus virginicus) were collected from the James River upstream, downstream, and adjacent to the station. Sediment samples were extracted using aqua regia (1HNO₃/3HCl/3H₂O) and diluted using nanopure ultra-deionized water. Whole body snail tissues were removed from their shells and combined into pooled samples of three individuals before being extracted using 65% HNO₃/ 30% H₂O₂ and diluted using nanopure ultra-deionized water. Extracted samples were then analyzed for 13 CCR-associated elements (Al, As, B, Cd, Ca, Cr, Cu, Fe, Pb, Mg, Mn, Se, Zn) using ICP-OES. Surface water samples were collected and assessed for species richness using eDNA MiFish primers (Jonah Ventures, Boulder, CO). Preliminary results indicate enriched Al, Cu, and Pb in surficial sediments downstream from the station as well as B and Mn bioaccumulation in S. virginicus tissues. Environmental DNA analyses have identified the presence of twenty-four fish species, six of which are commonly consumed by recreational anglers. Our results provide novel insight into the transport, deposition, uptake, and impacts of trace metal contamination near Bremo Power Station which can be used for future risk assessment and remediation efforts.