LOCATION.--Lat 42°01'16.5", long 92°50'56.3"
referenced to North American Datum of 1983, in NE 1/4 NW 1/4 NE 1/4
sec.8, T.83 N., R.17 W., Marshall County, IA, Hydrologic Unit
07080208, 0.5 mi west from intersection of 230th Street and Quarry
Road in Marshalltown. (map)
GROUNDWATER RECORDS
WELL CHARACTERISTICS.--Depth 23 ft. Upper casing diameter 2 in;
top of first opening 18 ft, bottom of last opening 23 ft. Drilled
observation well, cased to 18 ft. All depths below land-surface
datum.
DATUM.--Land-surface datum is 863.94 ft above North American
Vertical Datum of 1988. Measuring point: top of casing, 1.50 ft above
land-surface datum, July 9, 1997, to present. Land-surface datum from
lidar digital elevation model.
PERIOD OF RECORD.--Water-level measurements, water years 1997,
1999, 2005, 2007, 2009-2014.
PERIOD OF DAILY RECORD.--Water-level records from April 2013 to
September 2014.
GAGE.--Water-level recorder.
WATER-QUALITY RECORDS
PERIOD OF RECORD.--Water years 1997, 2007.