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<br />A <br /> <br />Table 1. <br />Design Infiltration Rates <br /> <br />Soil Group Rate <br /> <br />1.60inlhr <br />0.80 inIhr <br />0.60 inlhr <br />0.30 inIhr <br />0.20 inIhr <br /> <br />(i) Infiltration volumes and facility sizes shall be calculated using <br />the appropriate hydrological soil group classification and <br />saturated infiltration rate from the Table 1 unless documented <br />onsite double-ring infiltrometer test measurements done to the <br />specifications of ASTM D 3385 and completed by a licensed soil <br />scientist or engineer indicate otherwise. All soils testing <br />including soil borings shall be done in the location of the <br />proposed infiltration BMPs. <br /> <br />Soil Textures <br /> <br />ASTM Unified Soil <br />Class S mbols <br />GW, GP, GM, 8W <br />SP <br />8M <br />MH <br />ML <br />GC, 8C, CL, OL, CH, <br />OH <br /> <br /> <br />B <br /> <br />C <br /> <br />D <br /> <br />0.00 inlhr <br /> <br />(ii) <br /> <br />(iii) <br /> <br />(iv) <br /> <br />anent pools tend to lose infiltration capacity over <br />not be accepted as an infiltration practice. <br /> <br />(v) Stormwater runoff must be pretreated to remove solids before <br />discharging to infiltration areas to maintain the long term <br />viability of the infiltration areas. <br /> <br />(vi) Design and placement of infiltration BMPs shall be done in <br />accordance with the Minnesota Department of Health guidance <br />called "Evaluating Proposed Stormwater Infiltration Projects in <br />Vulnerable Wellhead Protection Areas." (Final version to <br />govern) <br /> <br />(vii) Specific site conditions may make infiltration difficult, <br />undesirable, or impossible. These conditions are listed in Table <br />2 and may qualifY the applicant for Alternative Compliance <br />Sequencing. The applicant may also submit a request to the <br />District for Alternative Compliance Sequencing for site <br /> <br />06/12/2006 CRWD DRAFT <br /> <br />13 <br />