Preliminary sampling of the surficial aquifers in the Minnesota Moraine subregion indicate compliance with most drinking-water standards set by the U.S. Environmental Protection Agency (USEPA). Slightly elevated concentrations of nitrate nitrogen above background concentrations suggest possible effects of predominantly agricultural land use in the Moraine subregion. Nitrate-nitrogen concentrations ranged from less than 0.05 to 23 milligrams per liter (mg/L) in samples collected from 25 shallow wells during August through October 1993. Of 11 samples with nitrate concentrations that exceeded the detection limit of 0.05 mg/L, two samples had nitrate concentrations that exceeded the 10.0 mg/L USEPA drinking-water standard.

Historical water-quality data on surficial aquifers in the Red River of the North drainage basin were compared to data collected in the Minnesota Moraine subregion in 1993. Median dissolved-solids concentration of 340 mg/L in the Minnesota Moraine aquifers is less than concentrations commonly found in other surficial aquifers in the basin. Total uranium, radium 228, radon, and a large suite of pesticides and volatile-organic chemicals also were analyzed from the Minnesota Moraine water samples to characterize regional water quality, however, historical data on these constituents are limited. The herbicide atrazine was detected in 7 of the 25 wells sampled in 1993, with a maximum concentration of 0.08 micrograms per liter. Data from this study indicate a land-use effect on ground-water quality in the Minnesota Moraine subregion.