Water Resources Research Act Program

Details for Project ID 2015NC191B

Heavy metal anaysis, gene proxies, and stable isotoope tracers of coal ash contamination in the Dan River food web

Institute: North Carolina
Year Established: 2015 Start Date: 2015-03-01 End Date: 2016-02-29
Total Federal Funds: $19,619 Total Non-Federal Funds: $35,954

Principal Investigators: Anne Hershey, Parke Rublee, Martin Tsz-Ki Tsui

Project Summary: The goals of the proposed work are to trace the extent of mercury (Hg) and other heavy metal contamination in the Dan River food web and food web disruption that is derived from the coal ash spill, evaluate microbial pathways governing coal ash contaminant routing to the food web, and calibrate surrogates for coal ash contamination in food webs. Preliminary data collected ~ 2 months following the spill show that sediment Hg downstream of the spill site was elevated ~ 4-fold compared to upstream. Contamination of fish by Hg is already a public health concern, reflected in a consumption advisory that is in place for Hg in many water bodies in NC. Thus, quantification of food web Hg contamination in the Dan River below the discharge site is essential to evaluating human health risk derived from the coal ash spill, interpreting effectiveness of clean-up efforts, and providing information to managers. Approaches for meeting the goals will include analysis of coal ash metal concentrations in river sediments and food web components at multiple sites upstream and downstream of the spill; using multiple stable isotopes to evaluate food web disruption and quantify the portion of the contamination that is attributable to the spill; and using gene proxies to assess the microbial mechanisms that route coal ash metals into the food web. Of four objectives, objectives (1) and (2) of the proposed work will answer the research question: How much metal contamination and food web disruption has occurred in the Dan River food web due to the February 2014 coal ash spill? Objectives (3) and (4) will address the research question: How well do gene proxies for microbes that chelate metals or methylate Hg predict coal-ash derived heavy metals in the Dan River food web? The approaches used can readily be applied to long term Dan River monitoring or to other coal ash spill sites.