Minnesota Geological Survey
Report of Investigations  RI-61.

Hydrogeology of the Paleozoic Bedrock in Southeastern Minnesota, A.C. Runkel, R.G. Tipping, E.C. Alexander, Jr., J.A. Green, J.H. Mossler, and S.C. Alexander. 2003.  105p. Associated maps in pocket of printed version provided here as plate1.pdf and plate2.pdf.

The pdf report should be viewed using Acrobat Reader 4.0 or higher
for best results.  If necessary, download this file as binary, not ASCII format. 
Also available as a printed report; contact the MGS Map Sales office at 612-627-4780, ex. 238 for price and availability.