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000112 {` <br /> • <br /> 7 <br /> The assimilative capacity of these constituents is determined for a potential land <br /> treatment site by assigning an assimilative capacity to the selected crop to be grown <br /> on the site. Assimilative capacities vary for each crop. The range in nutrient <br /> uptake for various crops is from 600 lbs/ac/yr of nitrogen uptake for bermudagrass to <br /> 200 lbs. of nitrogen/acre/year fora forested site. Depending on the crop selected, <br /> the assimilative capacity will vary. Assuming the stand of fescue will remain on the <br /> site, then the area required to assimilate the process constituents in the waste <br /> stream is calculated as <br /> Nitrogen: <br /> 1902.6 lbs-N/yr = 7.61 ac. <br /> 250 lbs-N/ac/yr <br /> Phosphorus: <br /> 661 lbs-P/yr = 6.3 acres <br /> 100 lbs-P/ac/yr <br /> Organics <br /> 4566 lbs-Organics/yr = 2.3 acres <br /> 2000 lbs-Organics/ac/yr <br /> The constituent requiring the largest land mass for assimilation does appear to be <br /> the hydraulic load. Based on the data available, a land treatment site containing <br /> approximately 8 acres will be required to assimilate the most restrictive of the <br /> constituents encountered at the site Since the site appears to contain well over <br /> this land area, the site does not appear limited as a receiver for wastewater. The <br /> water balance calculation used to determine the hydraulic load is based on both field <br /> measurements and published data A double tube infiltrometer was used to determine <br /> the volume of water which will move through the soil under near saturated conditions. <br /> Saturated conductivity is greater than unsaturated conductivity, but given the long <br /> delays between waste application, there have been no problems associated with <br />