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Fdeternnined r period instead of a one hour test period to induce maximum soil saturation. The rate obtained was 7.0 minutes per inch (mpi) for the 24 inch boring and 8.6 mpi oring. These perc rates do not exceed(are not faster)than the value of< 1 mpi USEPA Onsite Wastewater and Treatment and Disposal Systems. The second test was the Double Ring Infiltrometer test(ASTM D-3385)which measures the rate of one-dimensional water infiltration and flow through the soil/water interface. This test is more representative of the hydraulic conductivity properties of the soil than the standard percolation test, particularly with respect to measuring infiltration at the soil/effluent interface. Since a filter bed design will be installed, and the soil/effluent interface will be approximately 18 inches below grade, the Infiltrometer test was conducted at this depth. Test results as calculated on the field test form indicate a rate of 11.9 centimeters/hour(cm/hr), or 12.8 mpi under saturated soil conditions. This translates to an application rate of 0.757 gallons/8Z/day, according to published sewage application rates correlated with percolation rates. B. Soil Chemical Test Results As referenced above,two soil samples were submitted to the laboratory for analytical testing. The attached Soil Analysis Report denotes the samples from 24 IN and 8 FT. Analyzed constituents relating to nitrate loading include the organic matter content of the soil,pH, Cation Exchange Capacity (CEC), the nitrate-nitrogen (NO3-N) content. Of significance is the nitrate- nitrogen concentrations at each depth, revealing a medium concentration of 16 ppm NO3-N at 24 inches and a low concentration of 10 ppm NO3-N at the 8-ft depth. The denitrification capacity of the soil is predominately dependant upon the abundance of an organic carbon substrate, high soil moisture content leading to anaerobic environment, and high soil pH. The organic content of the soil is low and the pH is acidic near the surface and slightly basic at eight below grade. Although saturated soil conditions may develop near the soil/effluent interface, sufficient organic carbon substrate and an alkaline soil pH may not promote deni- trification to an acceptable extent. As discussed below, by utilizing peat at the soil/effluent interface will theoretically advance the denitrification potential. III. GROUNDWATER TEST RESULTS There are two wells on the subject property. One well is an open casing on a two-foot high pedestal that served the home before demolition. It is our understanding the second well was actually a test boring to install a well. The test borehole location is clearly marked with stakes which was witnessed by Mr. Larry Godinho from EHD during the perc tests. It is located approximately 125 feet northwest and cross gradient of the perc test locations. Page -3 �J - Che.vwy CorrsuCting