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groundwater surface between the stream channel and the adjacent floodplain to the north under <br />such an event. Please provide. <br />10. Please quantify the velocity and volume of flow expected as well as magnitude of flood event <br />required to produce a "bankfull" event in the adjacent reach of the St. Vrain River. Also, please <br />quantify or characterize the expected groundwater surface between the stream channel and the <br />adjacent floodplain to the north under such an event. Please provide. <br />11. Please clarify the criteria the applicant used to determine the number of spillways to install in <br />the reclaimed lake. Since the reclaimed lake and sluny wall installation will be adjacent to a <br />reach of the St. Vrain River that is over 1 mile in length, the applicant will need to quantify the <br />number of spillways needed and the spacing interval needed to ensure that floodwaters from a <br />100-year flood event will be discharged back safely to the main channel of the St. Vrain River <br />within a reasonable period of time and also maintain the structural integrity of the slurry wall <br />installation as well as the surrounding area. Please provide. <br />12. Review of the Reclamation Plan Maps provided indicates that the lake edge ranges from 100- <br />300 feet from the north bank of the St. Vrain River. The exact location of the slurry wall <br />between the lake edge and north bank of the river is unknown. Please provide a structural <br />analysis that verifies the minimum width or buffer of soil needed on either side of the slurry wall <br />to provide adequate support during saturated soil conditions, as well as under a rapid drawdown <br />scenario. Please provide. <br />6.4.7 EXHIBIT G -Water Information <br />13. In conformance with Rule 3.1.6(1), please verify whether there are any registered wells <br />within six hundred (600) feet of the proposed slurry wall installation. If yes, please provide a <br />map exhibit which shows the location and describes the ownership of each registered well. <br />(Wells registered with the Office of the State Engineer). Please respond. <br />14. ht conformance with Rule 6.4.7(1), please state affirmatively whether the proposed slurry <br />wall installation is expected to directly affect surface or groundwater systems within the affected <br />land and surrounding area. <br />I5. In conformance with Rule 6.4.7(2)(b), please provide a characterization of the alluvial aquifer <br />in the affected land and surrounding area which includes the following: <br />• Hydraulic gradient, and direction of groundwater movement <br />• Description of the St. Vrain Creek for the reach adjacent to the slurry wall installation <br />(gaining or losing stream, channel stability, bank stability, presence of riparian <br />vegetation) <br />• Description of the normal surface/groundwater interaction and function throughout a 12- <br />month cycle in the affected land and surrounding area (including St. Vrain River) <br />