|HRUBY, CLAIRE - Iowa Department Of Natural Resources|
|LIBRA, ROBERT - Iowa Department Of Natural Resources|
|FIELDS, CHAD - Iowa Department Of Natural Resources|
|KOLPIN, DANA - Us Geological Survey (USGS)|
|HUBBARD, LAURA - Us Geological Survey (USGS)|
|WICHMAN, MICHAEL - Iowa State Hygienic Laboratory|
|HALL, NANCY - Iowa State Hygienic Laboratory|
|SCHEULLER, MICHAEL - Iowa State Hygienic Laboratory|
|FURLONG, EDWARD - Us Geological Survey (USGS)|
|WEYER, PETER - University Of Iowa|
Submitted to: Iowa Department of Natural Resources
Publication Type: Government Publication
Publication Acceptance Date: 1/6/2015
Publication Date: 5/1/2015
Citation: Hruby, C., Libra, R., Fields, C., Kolpin, D., Hubbard, L., Borchardt, M.A., Spencer, S.K., Wichman, M., Hall, N., Scheuller, M., Furlong, E., Weyer, P. 2015. 2013 Survey of Iowa groundwater and evaluation of public well vulnerability classifications for contaminants of emerging concern. Iowa Department of Natural Resources. May 2015.
Technical Abstract: Groundwater supplies drinking water to about 80% of Iowa’s 3 million people, with over 2 million of these people obtaining their drinking water from public water supplies (PWS). Such PWS are required by the United States Environmental Protection Agency (US EPA) to monitor finished water for a variety of chemical, physical, and biological contaminants to protect public health. The remaining 300,000 Iowans rely on groundwater for their drinking water obtained from unregulated private wells. Pharmaceuticals, viruses, and other contaminants of emerging concern (CECs) are of increasing public concern. The chemical CECs have commonly been found in aquatic systems including groundwater. While there is mounting evidence that exposures to select CECs can affect aquatic and terrestrial organisms, potential effects to human health have not yet been identified. There has been reported incidence of acute gastrointestinal illness when these viruses have been found in nondisinfected municipal drinking water. In addition to the primary and secondary drinking-water contaminants that PWS are required to monitor under the Safe Drinking Water Act, the US EPA continues to evaluate potential contaminants on their “Contaminant Candidate List” (CCL) to determine appropriate standards. Contaminants needing further assessment are listed under the Unregulated Contaminant Monitoring Rule 3 (UCMR 3), which requires additional monitoring from a subset of PWS for a combination of metals, volatile organic compounds, hormones, viruses, and perfluorinated compounds. This is the first time the UCMR list includes CECs. The CCL was last updated in 2010, and is scheduled to be updated every 6 years. These lists will likely be revised to include other CECs as new analytical methods become available, detection levels improve, and health effects are studied. In order to determine whether selected CECs, pesticides, and UCMR 3 contaminants occur in Iowa’s aquifers prior to treatment, we conducted targeted sampling and analysis of raw groundwater from a strategically selected population of 66 PWS wells in 2013. A total of 208 unique parameters were measured, including 109 pharmaceutical compounds, 35 pesticide compounds, 19 metals, 5 microbial indicators, 3 bacterial pathogens, and 10 groups of human and animal viruses. Concurrent analysis of this untreated groundwater for 20 basic water-quality parameters and major ions, 5 nutrients, and tritium provided context for the potential occurrence of CECs. The sampling network represented all major aquifers in Iowa and a broad set of well characteristics. This study represents the first comprehensive examination of CECs in Iowa’s groundwater conducted to date, and one of the first conducted in the United States. This project will further understanding of CECs in groundwater, help assess future safe drinking water program needs, guide source water protection activities for both public and domestic wells, evaluate choice of fecal indicators for the Groundwater Rule in Iowa, and serve as a foundation for future epidemiological studies.