LOCATION.-- Lat 41°55'52", long 88°46'56" (NAD of 1927), in SW1/4SW1/4NE1/4 sec. 21, T.40 N., R.4 E., Hydrologic Unit 07090006, Well 10 (Illinois Environmental Protection Agency 11406), within De Kalb. Owner: City of De Kalb.

AQUIFER.-- Ancell Group of Ordovician age through Ironton and (or) Galesville Sandstones of Cambrian age.

WELL CHARACTERISTICS.-- Diameter unrecorded, depth 1,307ft, cased to 640 ft, open hole, drilled, public supply.

PERIOD OF RECORD.--

GROUND-WATER QUALITY: September 1986 (see Voelker and others, 1987); February 2002.