Relation of land use to nitrate in the surficial aquifer along the Straight River, north-central Minnesota, 1992-93

The U.S. Geological Survey studied the relation of land use to nitrate concentrations in the surficial aquifer along the Straight River near Park Rapids in north-central Minnesota (see adjacent map) during 1992 to 1993. Concern about health hazards to humans and livestock from use of ground water contaminated by nitrate prompted the study.

Data collected for this study included: (1) water levels from 38 monitoring wells; (2) nitrate-nitrogen concentrations in ground-water samples from 34 monitoring wells; and (3) land use determined for 2.5-acre parcels throughout the study area. Eighteen of the monitoring wells were installed as nested pairs; the other 20 wells were installed singly. The wells were screened near the water table except the deep wells of each nested pair, which were screened near the bottom of the aquifer.