Private domestic wells are the source of drinking water for approximately 25% of Wisconsin residents, and statewide it is estimated that 12% of these exceed health standards for nitrate concentrations.

Significant decline in the water table in the Wisconsin Central Sand Plain (WCSP) has caused concern over the increase in land area devoted to irrigated agricultural crop production.

Nitrate-nitrogen concentrations exceed the drinking water standard in nine percent of Wisconsin’s private wells andforty-seven community water system wells.

The study summarized here examined the impacts of groundwater pumping on Wisconsin Central Sands water resources. Prominent hydrologic studies in the 1960s and 1970s warned that the growth in groundwater pumping for agricultural irrigation in the region

While nitrogen fertilizers and other nutrient sources (e.g., manure, bio-solids, and legume credits) are valued for their ability to increase crop yields, a portion of nitrogen applied through these methods leaches to groundwater as nitrate.

Concern has recently emerged about a group of trace organic compounds identified in the aquatic environment which might affect reproduction and development of wildlife species and humans due to endocrine disruption (Colborn et al., 1996; Roefer et al., 2000).