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FFthebottom ssue regarding the groundwater(phreatic water) elevation in relation to septic ent is that there must be sufficient "treatment" distance. This is the distance between f a filter bed, leachline trench, or sump, and the highestanticipated depth to for the destruction of bacteria and viruses to occur. This treatment distance is cepted to be five feet. Therefore, sufficient distance currently exists between the bottom of the filter beds and the static water table depth. A sump-type septic structure is not recommended in this area, or for this project. To take advantage of the treatment potential of the indigenous soil, a filter bed or leachfield should be installed high in elevation to force septic effluent to travel the greatest distance before encountering the water table. For convenience and comparison purposes,test results for nitrate on the domestic water that serves the facility and for the water table sampled from all three backhoe test pits, are summarized below: WATER TABLE ANALYTICAL TEST RESULTS WATER TABLE ANALYSES ON-SITE DOMESTIC WELL - PUBLIC WATER SUPPLY NITRATE 13 ppm- Downgradient from Filter Bed 4.5 mg/L(5/2/02) AS NO, (2/4/02) NITRATE 31 ppm-Upgradient From Filter Bed 4.6 mg/L(5/3/01) AS NO, (2/4/02) NITRATE 314 ppm-Downgradient from Proposed 3.4 mg/L(12/3/96) AS NO, Truck Stop(7/13/02) From the test results, it is evident that there is a correlation between soil nitrate-nitrogen content and underlying groundwater table nitrate content. It is theorized that the nitrate concentration in the water table downgradient from the filter bed is lower than the upgradient due to soil saturation under the filter bed, which is promoting denitrification. With regard to the proposed Truck Stop parcel 255-26-13, it was to be expected that the water table would be high in nitrate since the soil nitrate-nitrogen concentration was high (44 ppm NO3-N). Test results for the domestic well which serves the entire facility indicate very low nitrate impact considering the nitrate concentration within the water table. These concentration differences can be most likely attributed to significant clay strata between the highest aquifers or zones of saturation and the deeper aquifers,that are being used for drinking water. In addition, there is ongoing research at the University of Colorado which suggests there may be a high denitrification potential within aquifers or saturated zones composed of a fine (vs. a coarse) soil fraction. 6 Chemey CotuultiV