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Equally important,mechanics will use"waterless"hand cleaner or wear nitrile gloves to either clean grease and oils from their hands,or prevent these substances from getting on their hands. After using waterless cleaners,hands can be washed with soap and water in the lavatory. 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 from a household. The scientific literature cites nitrogen concentrations in 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,as indicated in the scientific literature. B. CALCULATED NITRATE-NITROGEN LOADING NLS§3.4,3.5,3.6 The calculated nitrate-nitrogen impact to the soil and ultimately to the groundwater is difficult to determine due to the large number of variables involved and variables unknown at this time. These include: 1.) Impact from upgradient nitrate sources, 2.) Variability in wastewater flows from the American Crane Rental office facility,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/or unconfined aquifers and 6.) Potential landscape uptake of nitrogen. Wastewater researchers place the nitrogen reduction occurring in septic tanks at 10%to 20%. From the May 8, 2003 Symposium"Onsite Wastewater Treatment- Nitrogen Removal," Dr. Stuart Oakley of California State University Chico states that"approximately 20%of the total nitrogen generated is removed in the septic tank"(Ref. 16). As noted below, this estimate of 20%is used for nitrogen reduction occurring in the septic tank. Various scientific methods exist to estimate nitrate-nitrogen loading. This Study uses the Hantzsche/ Firmemore Formula to predict the average resultant concentration of nitrate-nitrogen in effluent recharge water from a conventional septic system. As calculated below,the property has been assessed on a total areal loading basis after the Lot Line Adjustment correlated with the total number of people potentially on-site every workday(n =255) of the year. These two factors primarily -- estimate the average resultant concentration of nitrate-nitrogen in the recharge water. As referenced, this concentration cannot exceed 10 ppm nitrate-nitrogen(45 ppm as nitrate). PREDICTED NITRATE-NITROGEN LOADING FROM A COMPLETELY BUILT- OUT AMERICAN CRANE RENTAL PROJECT USING AN E.H.D. APPROVED SEPTIC SYSTEM: 8