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2. Pond outlets designed to prevent short circuiting of the flow from pond inputs to the outlet; 3. A mirmimiaum depth for ponds of three (3) feet and conform to the design .specifications of the Stormwater Manual, 2001 4. An outlet skimmer to prevent migration .of floatables and oils for the. 2-year event;. and. 5. Access for future maintenance that is free of plantings. and impediments. D� Regional ponds and practices can be used to provide for storrnwater management based on the following ctxterma: 1..Regional ponds are required robe designed based"'on ultimate conditions for the contributing subwatershed. 2. Regional ponds are required to Toe constructed a . operativmal prior to cbnstructirig imperviousness within the contributing drainage area. Design.of all Best Management. Practices..(B1ps')wdl be consistent vvirh the Minnesota Stormwater:Manual, 2005; and as amended and the MPCA General Permit for Construction Activities,.2008, and:as amended. When using infiltration for volume control; .inf ltration ,v+a6nes and facilitT.Mes: shall be calculated using. the appropriate hydrological soil.;group classification'and,infiltration rate, and shall`:be capable of infiltrating the tNi*ed.volutne within 72 hours or`aAs' specified in the;MPCA General P.ermit.far Construction Activities, evaluating the infiltration ca ci ;.'of::;VIconstructed<'BMp: under post -development conditons, the �. In. e. g F� infiltration rates in the. Minnesota.Sty"rmwater;ltilanual should.b'e used: Select the design infiltration base on.. e least ermeable;sol`}3orizon within`the first eet beiow-the bottom elevation of the proposed. infiltrat on facili ':;site -spec inEiltratiori< rieasure iients completed by a licensed professional (as described in the .Minnesota,`5tormwater Manual, Novemlier`2005; .and as"a rien. e may be used in place of the values. in the Minnesota. Sto !...1 Mxoual,. and as approved by the'.City. " `uan ' `praCUces :'desi ed `i:to meet the. volume control regulation must provide All starmwater reten. ..-.,.p g� .. ;._.,., retreatroento£stgrmwater iunafpriar`tio':1riltratirig into the.groundwater system or discharging downstream. P;• ,,... ,`, Pretreatment methods must comply with the' 1 esota Stotinwater Manual, 2005, and as amended, for. the pro pose All" highly recommended and recommended design rxitexia.must be met, unless `specifically waived:by the Technical' Camtnissivn.:af VLAWMfl or RI, as. appropriate. I} To the zaxim.um.extent PW#cable, volume control shall be. fully met orisite (Section Z,.Subsection 24 Site conditions. may;make 3nfltration.undesirable ar it4possible. Th applicant must snake. soil corrections and/ investigate ot&a: r, ocations.oq he. site for feasible infiltration locations. Infiltration practices are not allowed: 1. For runoff frori fueling and vehicle. maintenance areas;. 2. Within hydrologic soil group D type: soils; 3. Within .some Wellhead Protection Areas . (Review Wellhead Protection Plans for additional guidance); 4. Within 50 feet. of a septic tank or dLin field; 5. On. areas. with less than three (3.) feet vertical separation from. the bottom of the infiltration system (. to the elevation of seasonal high. groundwater or top of bedrock. If the applicant claims that. infiltration is not feasible or allowed onsite; the applicant must provide supporting documentation and. follow: Section 2, Subsection 4. UpdatedMarch 14, 017 Gem Lake consolidated Land Use ordinance —Page.