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The two sail samples referenced above were submitted to A& L Western Agricultural Laboratory <br /> for analytical testing under the attached Chain of Custody. As noted on the Soil Analysis Reports <br /> found in Appendix 3, several constituents were analyzed. "Non-nitrogen" constituents that were <br /> tested relating to nitrate loading include the organic matter content of the soil,pH, and the Cation <br /> Exchange Capacity(CEC). <br /> The constituents listed above also play a role in the denitrification capacity of the soil. <br /> Denitrification ca acit is redominatel de en ntmDon the abundance of an or m carbon <br /> su s rate hi h soil moisture con ent leadin to anaerobic environment and hi h soil H. The <br /> organic content of the cherry orchard surface soils is a medium content, and the pH is alkaline. <br /> Saturated soil conditions may develop near the soil/effluent interface during irrigation and rainfall. <br /> Sufficient organic carbon substrate appears to exist, along with an alkaline soil pH, which appears <br /> to initiate denitrification to a measurable extent. <br /> Analysis of the nitrogen fractions included nitrate-nitrogen (NO3-N), ammonium-nitrogen(NH4 N), <br /> and Total Kjeldahl Nitrogen(TKN). TKN is the total of the ammonium fraction plus the organic <br /> nitrogen fraction. Therefore, by knowing the ammonium fraction, the organic fraction can be <br /> deduced. The test results reveal a medium (for agronomic purposes) nitrate-nitrogen concentration <br /> of 18 ppm in the cherry orchard surface soils. However, at 38 inches below ground surface, the <br /> nitrate-nitrogen concentration decreases by two-thirds of the surface concentration, down to 6 ppm <br /> NO3-N. This may be attributed to denitrification, as described above. There is no ammonium in the <br /> soil, therefore, the TKN analysis is measuring the organic fraction. Again, we see a dramatic <br /> decrease, probably due to oxidation, in the decomposition of the organic fraction from the surface to <br /> 38 inches below grade. This decrease leads to a theoretical decrease in nitrification potential. <br /> The results for the nitrogen fractions tested are summarized and tabulated in Table 1 below. In <br /> addition, the soil texture description is also denoted for comparison purposes. <br /> TABLE 1 <br /> SOIL SAMPLING PROFILE DATA - EXISTING CHERRY <br /> ORCHARD AND POTENTIAL FUTURE LEACHFIELD <br /> Soil Sample Depth Nitrate-Nitrogen Total Kjeldahl Ammonium Soil Texture <br /> Concentration Nitrogen(TKN) Concentration <br /> Concentration <br /> Cherry Orchard- 18 ppm 1401 ppm BDL * 32%Sand <br /> Composite of Surface to 32%Silt <br /> 10 Inches Depth 36%Clay <br /> Sample ID: COS 10 Clay Loam <br /> Future Leachfield 6 ppm 662 ppm BDL 44%Sand <br /> Sample- 34%Silt <br /> From 38 Inch Depth 22%Clay <br /> Sample ID: FLF38 Loam <br /> *Below Detectable Limits <br /> Page -3- <br /> Chesney Consulting <br />