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The two soil samples referenced above were submitted to A &L Western Agricultural Laboratory for analytical testing under the attached Chain of Custody. As noted on the Soil Analysis Reports found in Appendix 3, several constituents were analyzed. "Non-nitrogen" constituents that were tested relating to nitrate loading include the organic matter content of the soil, pH, and the Cation Exchange Capacity(CEC). The constituents listed above also play a role in the denitrification capacity of the soil. Denitrification capacity 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 cherry orchard surface soils is a medium content, and the pH is alkaline. Saturated soil conditions may develop near the soil/effluent interface during irrigation and rainfall. Sufficient organic carbon substrate appears to exist, along with an alkaline soil pH, which appears to initiate denitrification to a measurable extent. Analysis of the nitrogen fractions included nitrate-nitrogen (NO3-N), ammonium-nitrogen (NH4 N), and Total Kjeldahl Nitrogen (TKN). TKN is the total of the ammonium fraction plus the organic nitrogen fraction. Therefore,by knowing the ammonium fraction, the organic fraction can be deduced. The test results reveal a medium (for agronomic purposes) nitrate-nitrogen concentration of 18 ppm in the cherry orchard surface soils. However, at 38 inches below ground surface, the nitrate-nitrogen concentration decreases by two-thirds of the surface concentration, down to 6 ppm NO,-N. This may be attributed to denitrification, as described above. There is no ammonium in the soil, therefore, the TKN analysis is measuring the organic fraction. Again., we see a dramatic ' decrease,probably due to oxidation,-in the decomposition of the organic.fraction from the surface to 38 inches below grade. This decrease leads to a theoretical decrease in nitrification potential. The results for the nitrogen fractions tested are summarized and tabulated in Table 1 below. In addition, the soil texture description is also denoted for comparison purposes. TABLE 1 n � �l� AIVIFLINGPROFILE DATA EXISTING CHERRY SOILS S ORCHARD AND POTENTIIALF�UTURD LEACHFIELD Soil Sample Depth Nitrate-Nitrogen Total Kjeldahl Ammonium Soil Texture Concentration Nitrogen (TKN) Concentration I Concentration Cherry Orchard- 18 ppm 1401 ppm BDL * 32%Sand Composite of Surface to 321/6 Silt 10 Inches Depth 361%Clay Clay Loam Sample ID: COSTO r Future Leachfield 6 ppm 662 ppm BDL 44%Sand Sample- 34%Silt From 38 Inch Depth 22%Clay Sample ID:FLF38 Loan +Below Detectable Limits I Page-3- Chesney Consulting