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1 <br /> ' indicates a general south to north groundwater movement across the Deepe and Turnpike <br /> ' gravel sites. The groundwater at this site is recharged from South Boulder Creek (to the <br /> south), irrigation ditches and laterals, and from colluvial deposits (including a spring) from the <br /> ' west. <br /> ' The groundwater elevations identified on the groundwater contour map represent only the July <br /> 1996 water levels. Water levels in the spring and winter will probably be higher and lower, <br /> ' respectively. Currently the groundwater levels are controlled by a system of drainage ditches <br /> on the margins of the property and through the main body of the site. When the gravel <br /> ' operation ends and if these drainage ditches are filled, groundwater levels on the site may rise. <br /> ' Based upon the findings from the minimal groundwater analysis, modifications are being <br /> proposed to the final reclamation grading plan, see Exhibit IX-3. The area of most concern is <br /> ' the south and southwest portion of the site where the operator's current reclamation grades are <br /> two feet below the groundwater and shale elevations. It is recommended that this portion of <br /> ' the site be raised approximately two to three feet over what is being proposed in the current <br /> operator's grading plans. <br /> Additionally, it is recommended that a small channel remain around the interior periphery of <br /> the site plan so that rising groundwater elevations do not cause the growth of a wetlands <br /> environment. however, a two hundred foot wide channel is more than is necessary to assist in <br /> dewatering efforts. It is recommended that no more than a 200 foot wide channel remain on <br /> ' the site, otherwise additional wetlands will likely be created in this channel and will need to be <br /> mitigated at a later date when development of the site is pursued A drainage system would <br /> help control the possibility of high groundwater levels during the spring runoff and early <br /> summer irrigation season. In addition, we recommend the installation of four or five <br /> piezometers to monitor the effectiveness of the drainage system while the land remains in its <br /> final reclaimed state. <br /> ' -17- <br />