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Evaluation of Potential Impacts <br />From The Proposed Nix Property Sand and Gravel Operation <br />On Shallow Grountlwater Levels, Water Wells and Wetlands <br />For comparative purposes, WWE estimated the maximum amount of drawdown that is imparted <br />on the aquifer (i.e., at the well itself) from a 15-gallon-per-minute (gpm) domestic well and an <br />estimated 1,000-gpm irrigation well using the Theis non-equilibrium equation. Assuming a <br />transmissivity of 200,000 gpd/ft and a specific yield of 0.2, a 15-gpm domestic well will create <br />0.2 feet of drawdown after 365 days at a distance of 1 foot from the pumping well. An additional <br />0.5 to I foot of decreased saturated thickness due to lake leveling will not diminish this well's <br />capacity to produce its permitted 15 gpm yield. Similazly, an irrigation well pumping 1,000-gpm <br />for 365 days under similar aquifer conditions will produce a drawdown in the well of <br />approximately 10.6 feet at a distance of I foot from the pumping well. This drawdown is less <br />than half of the saturated thickness available at each of the irrigation wells in close proximity to <br />the Nix property. Similarly, 0.5 to 1 foot of additional drawdown at these wells due to lake <br />leveling will not diminish their capacity to produce their permitted yield. <br />4.3 <br /> <br />Evaluation of Potential Impacts on Wetlands <br />4.3.1 Water Sources for Wetland <br />The data and observations collected for this evaluation indicate that the wetland on the Sage Hill <br />Farm is sustained by both surface water and groundwater. <br />As shown on Sheet 4, the direction of groundwater flow is to the northwest and generally follows <br />the land surface. Data collected from piezometers MW-1 through MW-13, which are in or close <br />to the wetland, aze shown in Table 3. Figures SA and SB are cross-sections through the wetland <br />at piezometers installed in a north-to-south and east-to-west direction, respectively. The <br />following observations aze evident from the data: <br />• The depth to groundwater (during the growing season) beneath the wetland varied from <br />slightly above the ground surface to greater than 5 feet below the wetland towards its western <br />boundary. <br />011-074.000 Wright Water Engineers, Inc. Page 11 <br />April 2002 <br />