Iowa State-Wide Rural Well-Water Survey (SWRL) SWRL was conducted in 1988-1989 by the Iowa Department of Natural Resources, Geological Survey Bureau and the University of Iowa Center for Health Effects of Environmental Contamination. SWRL was designed to provide a statistically valid assessment of the proportion of private rural wells and rural Iowa residents affected by various environmental contaminants, as well as a cross-section of the quality of Iowa groundwater. A total of 686 wells, located in all of Iowa's 99 counties, were sampled for coliform bacteria, nitrate and other nitrogen species, 27 pesticides and 5 pesticide metabolites, and major inorganic ions. The systematically-chosen population of wells used for SWRL has been utilized by other studies. The SWRL design framework also systematically selected a subset of 10% (68) of all sites for a one-time repeat sampling, to assess temporal changes in water quality during the original survey. Subsequent to the original survey, the 10% subset was sampled two more times. For more information contact Bob Libra (Robert.Libra@dnr.iowa.gov) at (319)335-1585. Iowa State-Wide Rural Well-Water Survey Publications: The Iowa State-Wide Rural Well-Water Survey Design Report: A Systematic Sample of Domestic Drinking Water Quality: GSB Technical Information Series 17 (Abstract) The Iowa State-Wide Rural Well-Water Survey: Water-Quality Data: Initial Analysis: GSB Technical Information Series 19 (Abstract) The Iowa State-Wide Rural Well-Water Survey: Site and Well Characteristics and Water Quality: GSB Technical Information Series 23 (Abstract) The Iowa State-Wide Rural Well-Water Survey: October 1990 Repeat Sampling of the 10% Subset: GSB Technical Information Series 25 (Abstract) The Iowa State-Wide Rural Well-Water Survey: June 1991 Repeat Sampling of the 10% Subset: GSB Technical Information Series 26 (Abstract)