Persistence of Coal Combustion Residues in Freshwater Ecosystems and Consequences for Native Biota

EPA Grant Number: FP917801
Title: Persistence of Coal Combustion Residues in Freshwater Ecosystems and Consequences for Native Biota
Investigators: Brandt, Jessica Elizabeth
Institution: Duke University
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2015 through August 31, 2018
Project Amount: $132,000
RFA: STAR Graduate Fellowships (2015) RFA Text |  Recipients Lists
Research Category: Academic Fellowships

Objective:

The overarching aim of this research is to address the legacy-specific consequences of CCR contaminants in freshwater lakes that receive, or have historically received, coal-fired energy facility effluents. This is achieved with three specific research objectives which are: (1) to determine CCR concentrations in selected fish tissues collected from CCR-impacted and reference lakes and determine whether there are differences attributable to lake trophic status; (2) to examine the extent to which CCR-specific chemical signatures are apparent in aquatic ecosystems by isotope analysis; and (3) to measure CCR uptake, trophic transfer, and toxicity in freshwater biota with laboratory-based studies.

Approach:

The research studies three freshwater lakes in North Carolina that currently receive, or have historically received, CCRs by way of permitted effluent streams. Additionally, each lake is paired with a non-CCR-impacted reference lake of matching trophic status and all six lakes undergo identical field sampling plans. From each lake, surface water, sediment pore water, primary producer biofilms, and three species of fish are collected and characterized for CCR contaminant concentrations. Isotope analysis is subsequently conducted with surface and pore water samples and fish bone to determine whether CCR isotope signatures are apparent. Toxicity of field-collected CCRs is studied in two primary ways – in the first, zebrafish (Danio rerio) embryos are raised in sediment pore waters to assess developmental acute toxicity and in the second, adult fathead minnows (Pimephalas promelas) are fed a diet of field-collected biofilms to assess trophic transfer and reproductive impacts of CCR exposure via the food web.

Expected Results:

Due to their complex biogeochemical cycles, it is expected that some CCR contaminants will continue to be elevated in the water column, sediment pore water, biofilms, and fish tissues collected from CCR-impacted lakes relative to reference, non-CCR-impacted lakes. Because some of the contaminants are essential nutrients, it is expected that their concentrations will be higher in biotic environmental compartments (i.e. biofilms and fish tissues) than in environmental compartments (i.e. water, sediment) and that the food web will be the primary means of contaminant transfer to higher level predator species. Compared to previous assessments, it is expected that essential nutrient CCR contaminants will remain elevated in the food web despite cessation of effluent waste streams, while others will decline as they become sequestered in abiotic compartments without substantial interaction with biotic species

Supplemental Keywords:

coal combustion residuals, freshwater ecosystems, native biota, toxicity

Progress and Final Reports:

  • 2016
  • 2017