LOCATION.-- Lat 41°30'03", long 90°25'24" (NAD of 1927), in SW1/4SW1/4SE1/4 sec. 31, T.18 N., R.1 E., Hydrologic Unit 07090005, Well 1 (Illinois Environmental Protection Agency 31930), within Silvis Heights. Owner: Silvis Heights Water Corporation.

AQUIFER.-- Dolomite of Devonian? and Silurian age.

WELL CHARACTERISTICS.-- Diameter unrecorded, depth 554 ft, cased to 250 ft, open hole, drilled, public supply.

PERIOD OF RECORD.--

GROUND-WATER QUALITY: July 1985 (see Voelker and others, 1987); August 2002.