LOCATION.-- Lat 41°20'31", long 88°03'58" (NAD of 1983), in NW1/4NW1/4SW1/4 sec. 15, T.33N., R.10E, Hydrologic Unit 07120001, Piezometer PZ1, about 4.5 miles northeast of Wilmington. Owner: U.S. Forest Service, Midewin National Tallgrass Prairie.

AQUIFER.-- Glacial drift of Quaternary age.

WELL CHARACTERISTICS.-- diameter 1.0 inch, depth 14.9 feet, cased to 9.9 feet, slotted screen, observation.

PERIOD OF RECORD.--

GROUND-WATER LEVELS: October 2003 through September 2004

INSTRUMENTATION.-- Electronic data logger--60-minute recording.

DATUM.-- Land-surface datum is 621.86 ft above NAVD of 1988. Measuring point: Top of PVC casing, 5.0 ft above land-surface datum, October 22, 2003 through May 18, 2004; 3.5 ft above land surface after May 18, 2004.

REMARKS.-- Piezometer open to fine-grained deposits.

EXTREMES FOR PERIOD OF RECORD.--

GROUND-WATER LEVELS: Highest recorded water level, 0.77 ft below land surface datum, Aug. 29, 2004; lowest recorded, 5.29 ft below land surface datum, Aug. 25, 2004.