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III. NITRATE LOADING STUDY FINDINGS <br />A. WASTEWATER FLOW VOLUME PROJECTIONS AND CHARACTERISTICS <br />Wastewater Flow Volume Projections <br />To determine nitrate -nitrogen loading from any project, wastewater flow volumes must be <br />determined as accurately as possible. The total number of bedrooms the Assisted Living Facility <br />will have is three based on the Floor Plan in Appendix B. Considering two people per bedroom, <br />generating a theoretical 70 gals/day = <br />70 gals/person/day x 2 people/bedroom x 3 bedrooms = 420 gals/day Average Daily Flow (ADF) <br />Wastewater Characteristics <br />The domestic wastewater generated from the Facility will be composed of blackwater from toilets <br />and greywater from showers, laundry, hygiene, food prep, etc. The scientific literature cites <br />nitrogen concentrations in domestic septic effluent typically ranging from 17 mg N/L for graywater <br />to 140 mg N/L for blackwater toilet wastes. <br />Therefore, based upon the findings by researcher Bauman, et al, a value of 62 mg N/L in the septic <br />effluent will be used to calculate nitrate -nitrogen loading for this project (See Also Kaplan - aWk <br />Systems Handbook, Pg. 147). <br />Additionally, taking the assumed tenants of the Facility to consist of elderly people, there is a <br />higher likelihood of increased concentrations of medications. Consequently, it is proposed to <br />install two septic tanks in series in an attempt to capture these medicinal molecules in the sludge <br />and scum layers of the tanks. Chemotherapy and dialysis drugs should not be disposed of into the <br />septic system. Also, there should be minimal use of products that kill bacteria such as antibacterial <br />soaps, drain cleaners, quaternary ammonia, and bleach, as these products additionally stress the <br />bacteria in the septic system (See Heger, Onsite Installer). <br />B. CALCULATED NITRATE -NITROGEN LOADING <br />NLS§ 3.4, 3.5, 3.6. The calculated nitrate -nitrogen impact to the soil and ultimately to the <br />groundwater is difficult to determine due to the large number of variables involved and variables <br />unknown at this time. These include: 1.) Nitrate impact from upgradient sources, 2.) Variability in <br />wastewater flows, effluent nitrogen concentrations and dilution effects, 3.) Changes in groundwater <br />directional flow and elevation, 4.) And the denitrification potential of the indigenous soils. <br />HANTZSCHE/FINNEMORE EQUATION <br />INw, 0 - dib <br />Nr= (I+R) <br />Page -5- <br />Chesney Consulting <br />