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at approximately two houses per acre, over the life span of this development, nitrate from these systems may have impacted the underlying aquifers. Again, as with the results of the top aquifer, the test results of the deeper aquifers for a specific nitrate source is also indeterminable. The percolation rates obtained indicate a permeable soil. Effluent management is based on the permeability of the soil eventually reaching a long term application rate(LTAR) of approximately 0.5 to 1.0 gals/ft2/day due to biomat formation. Each system as desisned i conjunction with the 100%re la ement area if ever needed c adequately manage the septic e went under LTARs. Without sophisticated groundwater monitoring, it is unknown as to the exact groundwater depth at different times of the year, groundwater directional flow, and potential off-site nitrate sources impacting the subject property. A complete delineation of the nitrate contamination plume was not performed because it would have been prohibitively expensive and was not a requirement of the Environmental Health Department. Additionally,this report did not study potential impact from Sharpe Army Defense Depot which again, cannot be ascertained without expensive groundwater monitoring. Sufficient data has been collected and analyzed to determine that the groundwater table is currently an acceptable distance below grade for there to be adequate biological treatment of the septic effluent, according to published scientific literature. The minimum distance is generally recognized to be five feet. Mounding effects under the leachfields should be of little concern since the hardpan layer has been breached and the saturated zone is at a sufficient depth. Accurate "as-builts" of septic systems which may be installed in the future must be supplied to the Environmental Health Department and all applicable "distance" requirements must be strictly adhered to. It will be a requirement of the Environmental Health Department that any fixture development of this project will require an addendum to this Nitrate Loading Study. Also, as a monitoring requirement of the Department, subsurface soil samples and vadose zone water samples may be obtained from any or all of the project leachfxelds to be analyzed for nitrogen after approximately two years of use. 9 Valfey Ag Pesearck