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The required treatment volume is determined by the Watershed District as a function of new impervious area. The estimated treatment volumes required based on assumed impervious area coverage in the Zoning scenario and Maximum Build scenarios are 42 acre-feet and 43 acre-feet, respectively. The primary method of treatment will be the use of multiple ponds for the removal of total phosphorous and total suspended solids. Water reuse, bio-filtration, filtration, and stormwater wetlands are also suitable for treatment within the AUAR study area. The northwest portion of the AUAR study area located north of Rice Creek is comprised of Type A soils with highly permeable soils and is well-suited for infiltration practices. Generally infiltration may not be feasible in some areas located south of Rice Creek, depending on the level of soil and groundwater remediation achieved. Rice Creek Watershed District considers infiltration infeasible where soils are contaminated and “directs that infiltration not be used” per Table C2 of the District rules. Given the site history, the use of infiltration practices should be used on a case-by-case basis in areas where geotechnical and environmental testing indicates that soil contamination has been remediated. Stormwater will be conveyed to Round Lake and Rice Creek by means of underground storm sewer, vegetated swales, and wetlands. Conveyance systems will be designed in accordance with acceptable industry standards and in conformance with jurisdictional requirements. iii.W-D ATER APPROPRIATIONESCRIBE IF THE PROJECT PROPOSES TO APPROPRIATE SURFACE OR ().D,,, GROUNDWATERINCLUDING DEWATERINGESCRIBE THE SOURCE QUANTITY DURATION USE AND DNR.D PURPOSE OF THE WATER USE AND IF A WATER APPROPRIATION PERMIT IS REQUIREDESCRIBE .I, ANY WELL ABANDONMENTF CONNECTING TO AN EXISTING MUNICIPAL WATER SUPPLY IDENTIFY THE ,, WELLS TO BE USED AS A WATER SOURCE AND ANY EFFECTS ON OR REQUIRED EXPANSION OF .D MUNICIPAL WATER INFRASTRUCTUREISCUSS ENVIRONMENTAL EFFECTS FROM WATER , APPROPRIATION INCLUDING AN ASSESSMENT OF THE WATER RESOURCES AVAILABLE FOR .I,, APPROPRIATIONDENTIFY ANY MEASURES TO AVOID MINIMIZE OR MITIGATE ENVIRONMENTAL EFFECTS . FROM THE WATER APPROPRIATION Temporary dewatering may be required during project construction, particularly for buildings to be constructed with lower levels, for which caissons could be used to facilitate installation of footings and foundations. All water pumped during construction dewatering activities will be discharged in compliance with City, Watershed, and Minnesota Department of Natural Resources (DNR) requirements and the National Pollutant Discharge Elimination System (NPDES) permit, and consistent with approved Response Action Plans, as necessary. No discharge water will be directed to surface waters without prior retention in a temporary settling basin and a determination that no contamination exists. The developer will determine if groundwater is contaminated as a basis for determining discharge to storm sewer, sanitary sewer, or through a treatment process such as the existing groundwater treatment facilities. Temporary construction dewatering will require a Temporary Water Appropriations General Permit 1997-0005 if less than 50 million gallons per year and less than one year in duration. iv. SW URFACEATERS a) W-D ETLANDSESCRIBE ANY ANTICIPATED PHYSICAL EFFECTS OR ALTERATIONS TO WETLAND ,,, FEATURES SUCH AS DRAINING FILLING PERMANENT INUNDATION DREDGING AND VEGETATIVE .D REMOVALISCUSS DIRECT AND INDIRECT ENVIRONMENTAL EFFECTS FROM PHYSICAL , MODIFICATION OF WETLANDS INCLUDING THE ANTICIPATED EFFECTS THAT ANY PROPOSED .I(.., WETLAND ALTERATIONS MAY HAVE TO THE HOST WATERSHEDDENTIFY MEASURES TO AVOIDEG June 2014– Final AUAR13