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2. Explain in detail the pre and post impervious surface is sq. ft. in the submitted stormwater <br /> report. Also, separate the projects as phase 1 and phase 2 or explain the how the <br /> stormwater infrastructure works together. <br /> The preliminary plans have been updated with pre and post hardcover calculations for both projects and the <br /> stormwater report has been revised to match. The proposed stormwater basin will work together for both projects. <br /> The existing/proposed hardcover calculations show a reduction. Staff cannot verify these <br /> numbers. Please the hardcover numbers. <br /> 3. Within the stormwater report,include pre and post for volume and water quality treatment. <br /> The stormwater report has been revised to include this information. <br /> The report does not match calculated hardcover existing/proposed numbers.The discrepancies <br /> need further explanation. <br /> 4. MnDNR will follow up with comments regarding requirements for state floodplain and <br /> the Mississippi River Wild and Scenic and Recreational requirements. <br /> So noted. <br /> DNR comments were received on January 11,2019. See attached.Include a response to all of <br /> their comments. <br /> 5. The project must meet all state and city ordinance requirements for the floodplain regulation. <br /> No site improvements, including stormwater basin expansion and construction, are proposed within the <br /> 100 year base flood elevation boundary. <br /> Any improvement within the floodplain will need approval prior to installation. <br /> 6. Submit soil borings and infiltrometer tests for all proposed infiltration basin areas. <br /> Ageotechnical report was completed in 2017 for this site but does not include the area below the bluf where the <br /> infiltration basin is proposed or the area between the existingparking lot and the Elk Diver Lodge site. This <br /> report will be amended to include soil borings in these areas and submitted separately. <br /> Staff will review these documents once they have been submitted. <br /> 7. Submit soil borings for the proposed infiltration basin (within proposed area) in order to <br /> identify water baring soils.The infiltration basin details must meet state requirements and <br /> have a separation of 3' from the proposed bottom of the basin and water baring soils. <br /> Please refer to the response to the previous plan review comment. The infiltration basin will be designed, <br /> expanded and constructed to meet State and City requirements forgroundwater separation. <br /> Staff will review these documents once they have been submitted. <br /> 8. Stormwater pre-treatment is required prior to any proposed infiltration basins. <br /> Stormwaterpre-treatment will be provided using manhole sumps and si.Zed using the MIDS calculator <br /> during the construction documentsphase. <br /> Staff will review these documents once they have been submitted. <br /> 9. The plans show a basin bottom of 861.00 but the stormwater report lists 860.00. This needs <br /> to be addressed. <br /> The proposed infiltration basin will have a sloped bottom from elevation 863 down to elevation 862 but <br /> with no area that the 862 elevation.A basin profile detail will be included in the construction documents. <br /> Staff will review these documents once they have been submitted. <br />