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sources of graywater. Additional wastewater constituents may consist of coffee,juices or other similar type liquids to the system. No industrial or commercial chemicals, solvents, etc. are to be introduced into any of the septic systems. From the anticipated wastewater characteristics described above,the nitrogen emanating from the project may be at a higher concentration than what would normally be found in a typical domestic or household system. This can be attributed to the lack of a dilution effect that graywater from showers, laundry, and dishwashing would provide. The scientific literature cites nitrogen concentrations in residential septic effluent typically ranging from 17 mg N/L for basins, sinks, etc. to 140 mg N/L for toilet wastes. Therefore, considering a 70/30 percent usage for toilet water volume and sink water volume, respectively, a value of 103 mg N/L of septic effluent will be used to calculate nitrate-nitrogen loading for this project. A value of 66 mg N/L is typically used for residential calculations. B. PREDICTED NITRATE-NITROGEN LOADING The calculated or estimated nitrate-nitrogen impact to the soil and ultimately to the groundwater is difficult to determine due to the large number of variables involved. These variables include 1.)Future installation methods and design of on-site septic systems, 2.)Impact from upgradient nitrate sources, 3.) Variability in wastewater flows, nitrogen concentrations and dilution effects from effluent and stormwater recharge, 4.) Changes in groundwater directional flow and elevation, 5.) Denitrification potential within the soil environment and within the confined and unconfined aquifers and 6.) Landscape uptake of nitrogen. Various scientific methods exist to estimate nitrate-nitrogen loading. This study will use the Hantzsche/Finnemore Formula to predict the average resultant concentration of nitrate-nitrogen in effluent recharge water. As calculated below, each of the two parcels have been assessed individually on an areal loading basis correlated with the total number of people per workday. These two factors primarily dictate the average resultant concentration of nitrate-nitrogen in the recharge water, which cannot exceed 10 ppm nitrate-nitrogen (45 ppm as nitrate). As referenced, the current water table nitrate concentration has been measured at 168 ppm NO,, which should be considered the baseline. Depending upon the interpretation of the Porter-Cologne Water Act by the Environmental Health Department, it is assumed that the nitrate concentration of the resultant septic system effluent recharge cannot exceed this current water table concentration of 168 ppm NOS. The following_Qacu:lations demonstrate that the resultant effluent recharge water from the two parcels individually will not exceed 10 ppm NO,-N, or 45 ppm NO This is a 73% reduction i in nitrate concentration between the recharge effluent and the existing water table nitrate concentration. 9 Chesney Consulting