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GG 63 <br /> G e r�.:.. <br /> The yields per foot of depth for the wells for which information was provided by the owner <br /> as shown on Figure 1 are generally consistent with those shown in Figure 3. <br /> Conclusions Regarding Likely Well Yields <br /> Table 3 shows the required yields for individual wells and for one community well for <br /> different durations of pumping each day. Based on the foregoing analysis and the data in <br /> Table 3, wells installed on individual lots should provide yields that are adequate to supply <br /> two to three bedroom homes if the wells are drilled to depths of at least 150 feet. <br /> Individual Lot Wells Yield Requirenent <br /> GPM/FT of Well <br /> Required yield in gpm for pumping Depthfor well depths <br /> Bedrooms each day of: <br /> /lot Gallons/day 24 hours 12 hours 6 hours 100 200 <br /> 3 360 0.25 0.50 1.00 0.0100 0.0001 <br /> 4 480 0.33 0.67 1.33 0.0133 0.0001 <br /> 5 600 0.42 0.83 1.67 0.0167 0.0001 <br /> Single Community Well Yield Requirement <br /> Required yield in gpm for pumping <br /> No each day GPM/FT of Well <br /> Bedrooms/lot Gallons/day 24 hours 12 hours 6 hours Depth <br /> 3 13680 10 19 38 0.3800 0.0019 <br /> 4 18240 13 25 51 0.5067 0.0025 <br /> 5 22800 16 32 63 0.6333 0.0032 <br /> Table 3.-- Water Supply and Yield Requirements for the Project. <br /> Evaluation of Likely Well Performance <br /> Likely well performance was assessed by evaluating the potential for interference between <br /> adjacent on-lot wells and the likely drawdown while pumping for these wells and for a single <br /> community well. Based upon the conclusions in the USGS report that yields are generally <br /> greater for well sites that are on uplands and ridges than in flat lowlands, we located a <br /> potential community well at the location shown on Figure 3. <br /> The assessment of the performance of wells was implemented using a 3-dimensional <br /> groundwater flow model using the industry standard USGS MODFLOW model. The model <br /> covered the area shown in Figure 3 and comprised the following three layers and depths: <br /> Soil and Saprolite from 0 to 40 feet, Partially Weathered R (PWR) from 40 to 50 ft, and <br /> Fractured Bedrock from 50 to 200 ft. The hydraulic conductivity values for the Soil and <br /> Saprolite and PWR layers was set at 0.6 ft/day and 0.8 ft/day, respectively based upon <br /> 2 <br />