A high sensitivity airborne radiometric and magnetic survey of the Rice Like, Iron Mountain, Eau Claire and Green Bay 1:250,000 NMTS Quadrangles within the states of Wisconsin, Michigan, and Minnesota. A total of 10,340 line miles of high sensitivity radiometric and magnetic data were collected within these quadrangles. Traverse lines were flown at a spacing of 3.125 miles in an east/west direction at a 18.375 miles seperation. All data were collected utilizing a fixed wing aircraft and over 3,500 cubic inches of Nal crystal detector. Magnetometer data were collected utilizing a high sensitivity proton magnetometer. Data were recorded digitally at 1.0 second intervals aboard the aircraft. Navigation was performed using both visual and doppler techniques. All data presented in this report as corrected profiles of all radiometric variables, magnetic data, radar and barometric altimeter data, air temperature and airborne bismuth contributions. Radiometric data presented are corrected for Comptron Scatter, altitude dependence and atmospheric Bismuth. These data are also presented on microfiche, and digital magnetic tapes. In addition, anomaly maps and inerpretation maps are presented in relating known geology or soil distribution to the corrected radiometric magnetic data.

Final report analyzing aerial gamma ray and magnetic data in the Fairmont quadrangle, including a detailed geologic summary, interpretation report, reduced scale copies of all maps and profiles, histograms, and statistical tables for the quadrangle.

Report documenting results of an airborne high-sensitivity gamma-ray spectrometer and magnetometer survey of the Sioux Falls quadrangle in South Dakota, Iowa, and Minnesota, including data acquisition methods, a summary of data and outline of data presentation, area geology, and interpretation of results.

A report regarding airborne gamma-ray spectrometer and magnetometer survey of the Kenora Quadrangle, Minnesota.

A report regarding an airborne gamma-ray spectrometer and magnetometer survey of the Roseau Quadrangle, Minnesota

A report regarding an airborne gamma-ray spectrometer and magnetometer survey for the Duluth Quadrangle, Minnesota.

A report regarding an airborne gamma-ray spectrometer and magnetometer survey of the Bemidji Quadrangle, Minnesota

The following report presents results of an airborne high sensitivity gamma-ray spectrometer and magnetometer survey over the Quetico quadrangle, Minnesota.

The following report presents results of an airborne high sensitivity gamma-ray spectrometer and magnetometer survey over the Hibbing quadrangle, Minnesota.

The following report presents results of an airborne high sensitivity gamma-ray spectrometer and magnetometer survey over the International Falls quadrangle, Minnesota.

Introduction: The U.S. Geological Survey began a study in 1980 of the quality of water in the principal aquifers of Minnesota. The U.S. Environmental Protection Agency funded the study as part of the Underground Injection Control Program, which deals with disposal of liquid wastes beneath land surface. The initial report designated 14 aquifers in the State and provided general information about their geologic, hydrologic, and water-quality characteristics (Adolphson and others, 1981). This report, one in a series that describes individual aquifers in more detail, concerns the Ironton-Galesville aquifer.

From abstract: A preliminary quasi-three-dimensional finite-difference ground-water-flow model of the seven-county Twin Cities Metropolitan area was constructed and used to evaluate parameter sensitivity and adequacy of available data.

From abstract: This report uses water samples collected from two sites at the Wild Rice River in Minnesota to "establish baseline water-quality characteristics before construction of a reservoir near Twin Valley, Minnesota for recreation and flood control." It contains a map, graphs, and tables.

From introduction: The objectives of the study were to (1) determine the areal extent, thickness, and water-yielding capability of aquifers in the surficial deposits, (2) estimate the amount of water in storage in the aquifers, (3) determine the chemical quality of water in the aquifers and, (4) establish observation wells to monitor the effects of ground-water development on water levels and storage in the aquifers.

From purpose and scope: The purpose of this report is to describe trends in ground-water use in the Twin Cities metropolitan area, Minnesota, from 1880 to 1980. Water-use trends are discussed in terms of use category, volume of water used over time, aquifer, and well location.

From introduction: The objective of this study are to (1) determine the areal extent and thickness of the Buffalo aquifer and the general occurrence of deeply buried aquifers, (2) determine the potential for development of water supplies from wells in the Buffalo aquifer, (3) investigate and discuss annual recharge to the Buffalo aquifer and the potential for artificially recharging the aquifer, (4) determine the chemical quality of water in the aquifer and in area streams, (5) establish a network of observation wells for monitoring water levels and water quality in the aquifer, (6) determine the relationship between the aquifer and the adjacent streams, and (7) update the information on the flow characteristics of the streams. The main focus of this study is on water in the Buffalo aquifer and on flow characteristics of streams.

From abstract: This report is one of a series on the hydrogeology and water quality of the 14 principal aquifers in Minnesota prepared by the U.S. Geological Survey. The U.S. Environmental Protection Agency requested these studies because of the need for information to develop its Underground Injection Control Program.

Introduction: The U.S. Geological Survey began a study in 1980 of the quality of water in the 14 principal aquifers in Minnesota. The U.S. Environmental Protection Agency funded the study as part of the Underground Injection Control Program, which deals with disposal of liquid wastes beneath land surface. The initial report designated the 14 aquifers and provided general information about their geologic, hydrologic, and water-quality characteristics (Adolphson and others, 1981). This report, one in a series that describes individual aquifers in more detail, concerns the Upper Carbonate aquifer.

From abstract: This report is one of a series on the hydrogeology and water quality of the 14 principal aquifers in Minnesota prepared by the U.S. Geological Survey. The U.S. Environmental Protection Agency requested these studies because of the need for information to develop its Underground Injection Control Program.

From introduction: This report describes the quality of the waters and the potential water-quality impacts of redesigning a levee that surrounds the city of Chaska, in Carver County, Minn.

This report presents the results of water sampling from three lakes in Dakota County over an eighteen-month period. The author determined that "the lakes were shallow, non-stratified, and nutrient-enriched." It includes tables and other figures.

From abstract: This report is one of a series on the hydrogeology and water quality of the 14 principal aquifers in Minnesota prepared by the U.S. Geological Survey. The U.S. Environmental Protection Agency requested these studies because of the need for information to develop its Underground Injection Control Program.

From abstract: This report presents data collected from four lakes in Lakeville, Minnesota to determine water-quality characteristics and evaluate "changes that may occur in the lakes because of urbanization." It contains a map, graphs, tables, and a glossary.

Abstract: Alimagnet, Farquar, and Long Lakes, in Apple Valley, Minnesota, were sampled from 1973-79 to determine their physical and chemical characteristics. A storm-sewer inlet to Alimagnet Lake was also sampled during two storms in 1978. The 1976-77 drought caused a more noticeable effect on the quality of the lakes than any other factor. Chloride concentrations were 10 to 15 milligrams per liter before the drought, but increased 2 to 4 times during the drought. Dissolved solids reacted similarly . Dissolved oxygen and pH were governed mainly by biological activity. In February 1977, dissolved-oxygen concentration was less than 0.5 milligrams per liter in the three lakes. Ratios between mean total nitrogen and mean total phosphorus ranged from 22:1 to 26:1. Tropic-state indices indicate that the lakes are eutrophic. Blue-green algae dominated the phytoplankton populations. Storms sampled at a storm-sewer inlet to Alimagnet Lake showed higher concentrations pf chromium, copper, nickel, and zinc than of lead, arsenic, cadmium, and mercury. Total phosphorus for the September 1978 storm had a concentration of 1.7 milligrams per liter, which means that approximately 29 pounds entered the lake during the 5.5-hour sampling period.