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4 067 <br /> attached, the deep, well drained Georgeville and Herndon-like soils can <br /> accommodate a daily wastewater flow of approximately 1000 to 1200 gallons/day. <br /> The .actual wastewater flow which can be accommodated in this area will depend <br /> on the size of the area. Careful determination of the areal extent of the <br /> well-drained soils is essential and must be accomplished on a plat map of the <br /> site. Any waste flow in excess of the 1000 to 1200 gallons which can be <br /> accommodated in a subsurface system can be handled with a slow rate spray <br /> irrigation system and surface application of treated effluent. A water balance <br /> calculation is attached for the most restrictive of the soils encountered on <br /> the site. This is the Lignum-like soil which was encountered over the largest <br /> area of the site. The Lignum-like soil is considered to be very restrictive <br /> for any subsurface wastewater treatment and disposal options; however, with <br /> sufficiently like hydraulic loadings the Lignum-like soil can tolerate <br /> approximately 20 inches of additional hydraulic input per year - the surface <br /> application. If a slow rate spray irrigation system is used to handle a <br /> portion of the waste flow, then the following calculations apply for each of <br /> the residential facilities to be placed on a slow rate spray irrigation system. <br /> For these design calculations, the slow rate spray irrigation system is assumed <br /> necessary to accommodate the wastewater flow from a three-bedroom home with a <br /> design flow of 120 gallons/bedroom/day or 360 gallons/home/day. <br /> Each of the constituents contained in the waste stream must be assimilated <br /> at rates consistent with the ability of the soil, the site, and the vegetation <br /> to accommodate or accept those constituents. The hydraulic loading is based on <br /> a water balance calculation. The nutrient loadings, however, are assimilated <br /> at the capacity of the vegetation and of the site. Annual mass loadings and <br /> land area requirements for typical constituents contained in a waste stream are <br /> calculated below: <br />