Karst groundwater contaminants in western Illinois: comparison of current conditions with historical data

Abstract

The objective of this study was to provide data to help address the following questions: Have land use practices become safer for the environment and is this reflected in the water quality of our shallow karst aquifers? Or have increasing encroachment upon natural lands and potentially more intensive agricultural practices overshadowed any improvements in how we treat the environment? In short, how good a job have we been doing in the face of increasing development to protect shallow karst groundwater quality?Using the baseline from our 2000 study, we revisiteda series of caves and springs in the karst areas bordering the Mississippi River, collecting and analyzing water samples. Sample data included: 1) field water quality parameters; 2) bacterial colony counts, pesticides and herbicides; 3) anions, cations and other parameters; 4) pharmaceuticals and personal care products as pollutants (PPCPs); and 5) PCR identification of human and livestock waste sources.Q-­‐PCR specifically targeting Bacteroidalesis widely used for tracking fecal contamination from human, cow, and pig feces in different environments (Layton et al., 2006; Noble et al., 2006; Okabe et al., 2007; Shanks et al., 2007; Sauer et al., 2011). Others have listed possible contamination sources, including dog, cat, elk, deer, and gull (Field et al., 2003; Dick and Field, 2004; Dick et al., 2005). The targeted DNA biomarkers of Bacteroidales include 16S rRNA genes, functional genes, and genes encoding hypothetical proteins.