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Hydrogeologic Study August 22, 2001 Page 2 tor Yahara Materials plans to extract sand and gravel from a 59.8 acre g e parcel located in the NE 1/4 of Section 10 T8N, R6E, Mazomanie Township, Dane County, Wisconsin. Yahara Materials has already received a conditional use permit (CUP), #1721, from Dane County for mineral extraction (2001). In general, groundwater moves continuously from areas of recharge to areas of discharge. Groundwater recharge is the addition of water to the water table. Recharge areas are usually in topographical high places and in surface water detention basins. The water table is found either close to or at the land surface in discharge areas (streams, lakes, & wetlands). Regional groundwater contour maps contained within Bradbury (1999) and Dane County RPC (1999) show that groundwater at the subject property moves towards the northwest. Bradbury (2001) also determined that groundwater flows from southeast to northwest in the area. Halfway Prairie Creek is located 500 feet south of the subject site. This creek alters the groundwater south of the subject site towards the west. Groundwater monitoring has been conducted at the Mazo Land Disposal Landfill since 1976. The former landfill is located 2,000 feet north, downgradient, of the subject site. Liesch (1999) reported that groundwater at the landfill flows towards the northwest. Based on Plate 1: Water-table Elevation in Dane County (Bradbury, 1999), potential groundwater contours were drawn on the Yahara (2001) Reclamation Plan. Figure A, Water Table Map, shows groundwater flowing towards the northwest. Based on the potential groundwater contours and the existing ground contours, depths to the water table can be determined. The water table may be located 25 feet deep in the southern portion of the subject site. The water table may be located between 35 - 45 feet deep in the central portion of the subject site. The water table may be located 50 feet deep in the northern portion of the subject site. It appears that the water table drops approximately 20 feet across the subject site. The subject site is located on the western limit of glaciation. Stratified sand and gravel were deposited beneath the meltwater from the nearby glacier (stream sediment). The sand and gravel beneath the subject site is approximately 70 feet thick. Sandstone is located beneath the sand and gravel unit. The majority of private wells in the area are cased into the sandstone. Yahara Materials intends to sample four private wells located downgradient and one private well located sidegradient of the subject site. Groundwater samples would be analyzed for volatile organic compounds (VOC) by a WDNR certified