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r�2The organic matter in the perc test borings are low and very low, with the east end of the leachfield possessing twice the O. M. content than the west end. The nitrate-nitrogen concentrations reveal interesting results with the west end of the leachfield with twice the concentration of nitrate-nitrogen as the east end. It can be theorized that due to the increase in O.M. percentage at the east end,this has promoted denitrification and lowered the nitrate-nitrogen concentration at the east end by 50%. The pH of the soils is slightly acidic at 6.8/6.7 which will promote ammonium formation. However, ammonium molecular retention within clay micro-sites will be limited due to the relatively low clay content. The CEC is 5.1/5.7 which would be expected given the soil texture analysis of a sandy loam. A low CEC theoretically has a lower potential for adsorbing ammonium molecules. The clay content of the soil at 11% indicates a sufficient percentage of clay to maintain biochemical processes and mitigate a rapid perc rate. The backhoe test pit soil samples alsd reveal low O.M. percentages, as well as a slightly alkaline soil. The CEC is what is to be expected,with a very low concentration due to the sand soil at 12 ft. of interest, is the dramatic decrease in nitrate-nitrogen concentration of 23 ppm down to 3 ppm from 8 ft to 12 ft depth; an 87%decrease. This may be due to anaerobic conditions due to saturation where the loamy sand transitions to sand,thus promoting denitrification; or the nitrate-nitrogen molecules have quickly traveled through the sand. This is unlikely however, given the nitrate concentration directly above this sand stratum that would continually supply nitrate. NLS§3.3, SSS§5.3, 5.4. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil samples: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE I.D.DEPTH SOIL TEXTURE SOIL NITRATE- pH AND CLASSIFICATION NITROGEN CATION EXCHANGE CAPACITY CONTENT In meq/100g LFW40 Sandy Loam 6 ppm NO;-N 6.8 5.1 meq/1008 (Leachfield West 40"Depth) (SM,ML) LFE40 Sandy Loam 3 ppm NO;-N 6.7 5.7 meq/100(, (L eachfield East 40"Depth) (SM,ML) BTP8 Loamy Sand 23 ppm NO;-N 7.1 6.5 meq/100(, (Backhoe Test Pit 8 ft Depth) (ML,SM) BTP12 Sand 3 ppm NO;-N 7.5 2.4 meq/IOOg (Backhoe Test Pit 8 ft Depth) (SW) C. PERCOLATION TEST RESULTS SSS§6.2. As referenced,to assess the permeability of the existing shallow leachline soils, percolation test borings were completed at the east and west ends of the leachfield. Test locations are depicted on the project Site Plan produced by Advanced Design, Inc. Page -3- Chesney Consultimo