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V. CONCLUSIONS AND RECOMMENDATIONS The soil physical characteristics under the subject property reveal that most of the area for APN 179-160-20 has been subject to apparent compaction sufficient enough to negatively influence per as measured by percolation. Compaction has occurred from the parking of heavy machinery on this Parcel. To overcome this problem, an engineered system may be designed, or seepage pits may be installed in accordance with EHD requirements. Surface soils in potential disposal areas reveal a silty clay/clayey silt type soil with increasing permeability with increasing depth,based on the percolation test results. If a new septic system is proposed in the future, Infiltrator Chambers should be considered for leachlines. By distributing the effluent through these Chambers over a shallow distribution area, the favorable characteristics of the clay surface soils can be taken advantage of, such as: 1.) Ammonium absorption, 2.) Anaerobic microsites within the clay lattices preventing nitrification and promoting denitrification for nitrification that has occurred, 3.)Unsaturated flow conditions, 4.)Increasing the distance between the soil/effluent interface and the depth to groundwater, and 5.) Greater likelihood of pathogen destruction to prevent contamination of the underlying groundwater. As referenced in the Introduction, it will be the requirement of the EHD that if commercial development of Parcels APN 179-160-18 and 19 should ever occur,these two Parcels must connect to public water and sewer. It is generally recognized from soil physics,that water percolating from a fine-grained soil into a coarser-grained soil will be impeded until near saturation is reached in the fine/coarse-grained soil interface. These characteristics were observed in the subsurface soils and are beneficial for the prevention of nitrification and the promotion of denitrification. The nitrate loading calculations suggest a current effluent concentration that is below the MCL for drinking water and is roughly equivalent with the current nitrate concentration in the on-site domestic well water. It is important to recognize that all septic systems and disposal areas have a lifespan. This lifespan is unpredictable due to the numerous operational and environmental factors involved. Operational factors include checking toilets regularly to ensure there is no leakage. Environmental factors include biomat buildup that will occur at the soil/effluent interface which is a naturally occurring process. Biomat buildup is typically managed by allowing the disposal area to rest and rehabilitate naturally. L�� Chesney Consulting