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_ approximately five feet below grade. This saturated (phreatic)zone, is composed of fine grained material, with little coarse grained, sand-like material. Static groundwater levels have been measured at various locations under the subject property from approximately two feet in the summer (See Curtis Groundwater Determination Report),to approximately five feet below grade. This static water level can be considered the fust unconfined aquifer water, and it has been documented that groundwater is at a high elevation all year. The classification of subsurface water with respect to the encountered soil horizons are as follows: The soil water(vadose) zone lies between the surface and four feet below grade; the true capillary fringe is at approximately four to five feet below grade; and phreatic water (groundwater) is below five feet. Three boreholes were drilled on January 22, 1998 to measure current static water levels and determine groundwater directional flow. As illustrated on the attached schematic map, the upper groundwater is flowing toward the north. The following table represents each borehole surface elevation as surveyed (mean sea level) and static water level measurement: BORING No. GROUND ELEVATION WATER LEVEL MEASUREMENT GROUNDWATER ELEVATION 1 5.65 ft 4.5 ft 1.15 It 2 6.76 ft 5.2 ft 1.56 ft 3 7.85 ft 5.15 ft 2.70 ft To assess the current quality of groundwater under the project site, a sample was taken from the top of the upper groundwater (Boring No. 1) and from a domestic well adjacent to the project site, at 21102 South Lammers Road. The analyses (See Appendix), indicate relatively low impact from nitrate contamination. Other constituents analyzed for, along with comments are as follows: TOTAL DISSOLVED SOLIDS(TDs): A measure of dissolved material upon evaporation, specifically the salt content of water. 1000 mg/lis the MCL. TOTAL KJELDAHL NITROGEN(ncN): Quantification of the organic and ammonia fraction of nitrogen. Assesses the potential for nitrate formation. pH: Measures the hydrogen concentration and is important in the formation of nitrate. If the pH is below 7.0, the ammonium ion predominates and nitrate formation can readily take place. Above 7.0 and ammonia predominates and inhibits nitrate formation. 4 Naffey Aq P�searck