Initial Investigation into the Use of Phytoremediation to Address Legacy Pollution at a Virginia Site Affected By Acid Mine Drainage.

Legacy pollution, or remaining pollution from past activities for which no one is held responsible, is especially common in abandoned mine sites. The Contrary Creek ecosystem in Louisa County, Virginia, contains former pyrite mines that were last active in the 1920s, yet acid and metal contamination continues to affect the soil, stream, flora, and fauna. All sampled soils still demonstrate high levels of pollution, especially aluminum, lead, and zinc concentrations. Soil pH at all the sites was below 5, sometimes as low as 3. Our recent research showed that the metals accumulating in the soil due to the acid mine drainage (AMD) are associated with different soil fractions, properties, and depth, with each association holding various environmental implications. Our current research examines the role plants play in this contaminated ecosystem. The vegetation was surveyed and chemically analyzed from three sites along the stream to determine potential correlations of plant properties with various soil factors, especially pH and total and bioavailable metal fractions. The potential to use two well-studied plants, Pteris cretica and Chrysopogon zizanioides, for phytoremediation of the site was also investigated in relation to soil metal concentrations, pH levels, and site location. This information will allow us to better understand the nature of the AMD contamination at this site and the ecosystem’s response to the contamination.