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NLS§ 3.3. The attached texture analysis reveals the on-site soils at both test depths consists of a sandy loam, with sand, silt and clay percentages listed in Table 1 below. The clay content of the on- site soils can be considered medium. Denitrification potential exists, as discussed below. NLS§ 1.2. As noted on the attached Soil Analysis Report, the chemical analyses conducted quantifies several constituents that influence nitrate loading for this project. The important parameters for nitrate loading assessment are the organic matter and estimated nitrogen release (ENR), clay content, pH, cation exchange capacity (CEC), and the nitrate-nitrogen content of the soil. A. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS SSS§ 2.1. The organic matter from the 3-ft depth is a high percentage at 2.7%, with an ENR of 84 lbs/A and a low OM percentage of 1.1 at the 8-ft depth, with an ENR of 52 lbs/A. This ENR and OM numbers suggest there is a low-to-medium potential for future nitrate forming from the organic matter within the surface soils. Since septic effluent is composed predominately of ammonium (NH4), the pH, along with the CEC, will have significant influence on ammonium molecules. The pH of the soil is alkaline which may have the effect of promoting ammonia formation and not ammonium formation. Since ammonium is the precursor to nitrate formation, if NH3 is promoted, this will retard NH4 formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at -18 meq/100 g, which is a medium value. This suggests an average-to-high potential for the retention of ammonium molecules that may form for microbial assimilation within the soil. The nitrate-nitrogen concentration is high at 23 ppm in the surface soils indicating a medium-to-high potential for continued nitrate leaching. However, there is a substantial decrease in nitrate-nitrogen concentration at the 8-ft depth of 2 ppm, indicating a high denitrification potential. TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE ID AND DEPTH SOIL TEXTURE CLASSIFICATION SOIL NITRATE- NITROGEN CONTENT pH AND CATION EXCHANGE CAPACITY / z In meq/100g 36 IN. DEPTH Sandy Loam 23 ppm NO3-N 8.3 19.0 meq/100g 96 IN. DEPTH Sandy Loam 2 ppm NO3-N 8.6 18.4 meq/100g SSS§ 3.1-3.6. There is no septic system on the subject property, nor is there any record of a septic system ever on the property. There are many septic systems in the general locale surrounding the subject property. A very high number of 12 repairs/ additions permits to septic systems were found in the EHD files within the one-quarter mile study area from the property. This may be attributable to the fact that many of the failed systems serve residential structures that are several decades old. Page -2- Chesney Consulting