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RCWD Permit Number 14-104 stormwater. The filtration benches do not provide enough treatment to comply with the rules, however, the stormwater ponds have been sized to be in compliance with the water quality treatment requirement of Rule C.9(d). Pretreatment for the stormwater ponds will be provided by sump catch basins. Thus the project has complied with the Rule C.6 Water Quality Requirements. The submitted soil borings indicate that the majority of the project soils are CL or SC (hydrologic soil types C/D). The applicant performed soil borings throughout the project to document the existing groundwater elevation, to verify the hydrologic soil types, and to provide additional detail for specific soil layers. The soil borings indicate that the seasonally high water table approximately 18 feet below the surface, however, due to the low permeability of the soils infiltration is not feasible on the site. The applicant has provided hydrologic calculations for the 2, 10, and 100 -year 24-hour rainfall events which demonstrate compliance with the requirements of District Rule C.7. The site is within the District Flood Management Zone, and is in compliance with the rate reduction requirement in District Rule C.7(c). The proposed basins have a peak stormwater elevation of 936.6, and the proposed buildings will have a low floor/low entry elevation of 940.0 and are in compliance with the freeboard requirements of Rule C.9(g). 3. Wetlands — No wetlands are present on the site, and no wetland impacts are proposed by this project. 4. Floodplain — No regulatory floodplain is present on the site. 5. Erosion Control — The proposed erosion control methods include inlet protection, and silt fence. The applicant has also indicated that they will install earth dikes, sediment traps or basins, additional siltation fencing, and/or disk the soil parallel to the contours if they deem necessary. An NPDES permit is required for the project. The information listed under the Erosion and Sedimentation Control Recommendations needs to be submitted; otherwise, the project complies with RCWD Rule D requirements. 6. Documenting Easements and Maintenance Obligations — The applicant needs to provide drainage and flowage easements (if required by the City), a draft maintenance declaration, and a receipt showing recordation once the draft has been approved. 7. Previous Permit Information — RCWD File 14-134R contains pre -application information for the project. I hereby certify that this plan, specification or report was prepared by me or under my direct supervision and that I am a duly Registered Professional Engineer under the laws of the state of Minnesota. OAtzp:i ", i - I a - 15. Chris Buntjer MN Reg. No 48745 Katherine MacDonald MN Reg. No 44590 Rice Creek Watershed District Page 3 of 3 1/12/2015 Dra tnage P rea s a „ E c st Ctg proposed 1=fasting Proposed 1eoposeF- d : OF—Id""' 1=x sftng I Valentine Lake 4.94 3.53 10.20 5.37 23.24 18.59 8t)° of tt e etMstirg toa1 3 95 8 16 11859 The proposed basins have a peak stormwater elevation of 936.6, and the proposed buildings will have a low floor/low entry elevation of 940.0 and are in compliance with the freeboard requirements of Rule C.9(g). 3. Wetlands — No wetlands are present on the site, and no wetland impacts are proposed by this project. 4. Floodplain — No regulatory floodplain is present on the site. 5. Erosion Control — The proposed erosion control methods include inlet protection, and silt fence. The applicant has also indicated that they will install earth dikes, sediment traps or basins, additional siltation fencing, and/or disk the soil parallel to the contours if they deem necessary. An NPDES permit is required for the project. The information listed under the Erosion and Sedimentation Control Recommendations needs to be submitted; otherwise, the project complies with RCWD Rule D requirements. 6. Documenting Easements and Maintenance Obligations — The applicant needs to provide drainage and flowage easements (if required by the City), a draft maintenance declaration, and a receipt showing recordation once the draft has been approved. 7. Previous Permit Information — RCWD File 14-134R contains pre -application information for the project. I hereby certify that this plan, specification or report was prepared by me or under my direct supervision and that I am a duly Registered Professional Engineer under the laws of the state of Minnesota. OAtzp:i ", i - I a - 15. Chris Buntjer MN Reg. No 48745 Katherine MacDonald MN Reg. No 44590 Rice Creek Watershed District Page 3 of 3 1/12/2015