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dp T viruses to occur. This is generally accepted to be five feet. Therefore, sufficient distance currently exists between the bottom of a Ieachline trench and the static water table depth. f Two well logs from nearby domestic wells illustrates varied geological strata of clay, sand and sandy gravel down to depths of 200 ft. From these two well logs, it can be observed that the upper zone of saturation consists of a clay-type, fine soil fraction. There is ongoing research fcant denitrification potential within aquifers composed of a which suggests there may be a signi fine (vs. a coarse) soil fraction. p The top groundwater sample was analyzed for the nitrate concentration. Test results reveal the water table to have a-nitrate (as NO3) concentration of 52 ppm {mg/L); which is 13% over the MCL of 45 ppm NO3. To determine the extent of nitrate impact to the underlying drinking water aquifers, two water samples were taken: The first sample was retrieved from the domestic well at 265Q8 South Banta Road, which is Parcel 1. This well was drilled in October I997. There was a waiver from a 200- ft grout seal for this well, which is normally required for all wells in this area; therefore, this well has only a I00-ft grout seal. The second sample was taken from 26444 South Banta Road, which is Parcel 3. No records were available for this well; however, it is probably more than 30 yrs old and was drilled to a shallow depth. The test results are illustrated on the attached WATER ANALYSIS REPORT and indicate-37 ppm NO3 for the Parcel 1 well. This corresponds with a well test of a domestic well at 26457 S. Banta that tested at 34 ppm NO3 two years ago. The Parcel 3 well tested at 49 ppm NO3. The Maximum Contaminant Level (MCL) for nitrate (NO3) in drinking water is 45 ppm. Consequently, the drinking water aquifers exceed the MCL for NO3 by 4 ppm. DBCP and EDB were Below Detection Limits (BDL) and the Chloroform concentration supposedly originating from the All-Pure Chemical Company was 26 ,ug/L. There ► is no MCL for Chloroform. E. SURFACE WATER INFORMATION As referenced, there is a surface water retention pond for the existing development of Parcel 1 on the east side of the parcel. The other two parcels must have retention ponds if developed in the future. There should be no impact to impoundment water from any of the on-site Ieachfields as long as distance requirements are met. III. NITRATE LOADING STUDY RESULTS A. WASTEWATER FLOW PROJECTIONS AND CHARACTERISTICS In accordance with the request of the Environmental Health Department, this nitrate loading study is to quantify the number of people (employees, customers, etc.) the three subject parcels can support without exceeding the MCL for nitrate. To determine nitrate-nitrogen loading from the project, wastewater flows must be determined as accurately as possible. Typically, loading projections are based on the maximum or total number 5 Vaffery AB research