Date of Award


Degree Name

Master of Science


Geological and Environmental Sciences

First Advisor

Dr. Richard N. Passero

Second Advisor

Dr. W. Thomas Straw

Third Advisor

Dr. Lloyd Schmaltz

Access Setting

Masters Thesis-Open Access


Nitrate levels from 1,978 wells were compiled and analyzed to identify areas having levels above the Federal and State Drinking Water Standards of 10 ppm, identify possible sources of nitrate in each area and determine factors that produce high concentrations of nitrate in groundwater.

Eighteen areas in which nitrate concentrations exceeded 10 ppm were identified. County-wide, 465 (23 percent) of the wells for which data were available produced water with nitrate concentrations above drinking water standards.

Septic tank effluent is thought to be the most common source of nitrate in the problem areas. Agricultural practices are also likely nitrate contrbutors; however, in areas where they were found to be associated with high nitrate levels, septic tank systems were also present. Apparently there is more than one source of nitrate in these areas.

High nitrate concentrations in wells were found to be related to natural and cultural factors. These include land-use, soil type, glacial geology, well density, and well depth.

Included in

Geology Commons