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`. I SELECTED SOIL PROFILE DATA UNDER FALLOW LAND AREA OF PROPOSED LOT 3 and LOT 10 20 ft 5 ppm 8.5/16.7 37%Sand Under Proposed Lot 3 36%Silt Loam Sample 1D:20FT3 26%Clay 41 25 ft 5 ppm 8.4/17.7 37%Sand I!nder Proposed Lot 3 36%Silt Loam Sample to:25FT3 26%Clay 5 it 3 ppm 8.6/15.7 65%Sand Under Proposed Lot 10 12%Silt Sandy Clay Loam Sample ID:5'-10 22%Clay loft 4 ppm 8.6/15.7 51%Sand Under Proposed Lot 10 22%Silt Sandy Clay Loam Sample m:10'10 26%Clay 15 ft 4 ppm 8.6/15.7 65%Sand Under Proposed Lot 10 18%Silt Sandy Loam Sample 11):15'10 16%Clay 20 ft 4 ppm 8.6/15.7 73%Sand Under Proposed Lot 10 12%Silt Sandy Loam Sample ID:20'10 14%Clay 25 ft 3 ppm 8.6/15.7 69%Sand Under Proposed Lot 10 16%Silt Sandy Loam Sample m:25'10 14%Clay 2. SUBSURFACE SOIL CHEMISTRY DIRECTLY UNDER ON-SITE LEACHFIELD NLS§ 3.3 A soil sample was retrieved 18 inches directly below the drain rock which served the on- site residential septic system for the past -50 years. The soil under the leachline was excavated and exposed using a front-end loader used to raze the on-site residential structure. The soil under the drain rock was very moist indicating that effluent was percolating through the drain rock and into the soil under the leachline trench. After sampling,the soil was taken to A & L Western Agricultural Labs under the attached Chain of Custody. The test results for the soil under the leachline show a very high nitrate-nitrogen concentration at 97 ppm NO3-N,which is approximately 19 times higher than found in soils under lots 3 and 10. It is theorized that as the septic effluent travels through the drain rock, which must have a sufficient aerobic environment,the effluent is nitrifying. The nitrate then enters the underlying soil which has a 22%clay content. However, at the sample depth, the effluent has not traveled a sufficient distance for the clay soil to promote denitrification. It was my understanding that an excavator was to be used in demolition of the old house and related structures, and not a front-end loader. An excavator would have provided an excellent means of soil sampling at five-foot intervals directly under the leachline down to a depth of 25 feet. An analytical soil profile could have been developed showing if denitrification is occurring with increasing depth. The following Table illustrates the nitrogen fraction concentration, and other pertinent data such as soil particle analysis found in the soil 18 inches under the leachline trench: Page -4- Chesney Consulting