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14. In conlimnancc with Rulc 6.4.7(1), please state a(limtatively whether the proposed <br />slurry wall installation is expected to directly affect surface or groundwater systems within <br />the atTcctcd land and surrounding area. FULLY' ADDRESSED <br />I $. In conforma»cc with Rule 6.4.7(2-(b), please provide a characterization of the alluvial <br />ayui fer in the affected land :utd surrounding area which includes the following: <br />• I lydraulic gradient, and direction of groundwater movement <br />• Description of the St. Vrain Crock for the reach adjacent to the slurry wall <br />installation (gaining or losing stream, channel stability, bank stability, presence of <br />riparian vegetation) <br />• Description of thr normal surface groundwater interaction and function throughout <br />a 12-month cycle in the affected land and surrounding area (including St. Vrain River) <br />FULLY ADDRESSED <br />16. In conformance with Rule 6.4.7(2)(6), please provide a representative cross sectional <br />diagram for each of the three (3j nrinrd lakes which adcyuately depicts the Icatures of the <br />alluvial ayuil'er within the affected land and surrounding area. The cross sectional diagr:un <br />should he drawn to scale and provide the tollowing information: <br />• Existing reclaimed excacation(s- and lake high water mark(s) <br />• Groundwater (peizometric) surface <br />• Proposed slurry wall installation <br />• St. Vrain Stream Channel (from top of\urth Bank to top o(South Bank) <br />• 100-fear Flaxlplain boundaries (existing & proposed) ~@ elevations <br />• St. 1%rain Crcck - Floodway boundaries <br />• Any existing registered wells within 600 feet of the slurry wall installation <br />• Ordinary high water mark of the St. Vrain River <br />• Inven of the St. Vrain River <br />• Significant wetlands, and;or woody riparian vegetation <br />FULLt' ADI)RF.SSED <br />17. In confomtance with Rule 3.I.G(l ), plc:tse quantify the vertical and horizontal extent of <br />impact to the groundwater surface and normal groundwater recharge or Ilo+v pattern(s) <br />upon completion of the slurry wall installation. It is the Division's experience wish other <br />slurn• wall installations that there is typically a "mounding" and "shadowing" etlirt. <br />These impacts arc typically yu:mtified through gmnndwater modeling and field ceriticd <br />through a grounehvater monitoring program. :\Iso. please describe and show on a map thr <br />location of any water ('eaturc (well, spring, wetland, riparian vegetation) or pernrancnt <br />man-made structure (leach field, sewer line, highway bridge support, septic tank, etc) that <br />is within the scope (radius) of inllucncc of tither mounding or shadowing, and assess the <br />impact to such feature or stnrcture. Finally, please describe the mitigation measures that <br />will 6e employed to minnnize the impact on the various water features or man-made <br />stnrctures. FULLY' ADDRESSED <br />13. Please provide a map which depicts the lateral extent o1 the "Floodway' and 100-year <br />Iloudplain for the. St. Vrain River, elevation of the 100-year flood surface, location of the <br />existing reclaimed lakes, artd proposed slurry wall installation. FUt.LI' ;\DDREtiSI:D <br />s <br />