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The attached texture analysis reveals the on-site soils at this depth consists of a loamy sand,with sand, silt and clay percentages of 80%, 12%and 8%respectively. Although the clay content of the on-site soils can be considered comparatively low, denitrification potential still exists. 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. SSS§2.1. The organic matter is low at 0.7%and the ENR is low at 43 lbs/ac. This OM and ENR concentrations suggest there is a low potential for future nitrate forming from organic matter. Since septic effluent is composed predominately of ammonium(NH4), the pH, along with the CEC, have significant influence on ammonium molecules. The pH of the soil is slightly 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 4.8 meq/100 g,which is a low value. This suggests a low potential for the retention of ammonium molecules that may form for microbial assimilation within the soil. The nitrate-nitrogen is a medium concentration at 18 ppm indicating a medium potential for continued nitrate leaching. NLS§3.3. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil sample. TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTH SOIL TEX'T'URE SOIL.NITRATE- pH AND CLASSIFICATION NITROGEN CONTENT CATION EXCHANGE CAPACITY In meq/100g 36 IN.DEPTH Loam Sand 18 ppm NO.-N 72 4.8 me /100= SSS§3.1-3.6. The existing septic system for Mr. Heatwole's house is found in Appendix E, which was a replacement/upgrade to the original system. There are many septic systems in the general locale surrounding the subject property. A surprisingly high number of 12 repairs/ additions permits to septic systems were found in the EHD files within the one-half mile study area from the property, and are also found in Appendix E. This may be attributable to the fact that many of the failed systems served residential structures that are decades old. As noted, all septic systems have a lifespan and it appears that in this locale, a lifespan of three or more decades may be expected. Page -2- Chesney Consulting