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The subsoils in the upper 3 feet of the existing street and driveway as indicated in the soil <br /> boring logs and as discussed below; <br /> Borings 1,2,3,4,and 5 subsoils under the existing Bituminous, Class 5 Gravel and <br /> silty sand fill (found in Borings 2 and 3) consist of sandy clay (Sandy Clay Loams <br /> AASHTO A-4 or Clays AASHTO A6). <br /> After removal of the existing bituminous pavement section the stability of the pavement <br /> subgrade should be evaluated by means of a test roll prior to paving. All unstable areas of subgrade <br /> should be removed and replaced with additional class 5 aggregate. The bottom of the subgrade <br /> should be compacted prior to adding new aggregate base material.New fill should be compacted per <br /> the Specified Density Method (MnDOT Specification 2105.3fl). <br /> Streets and driveways should have clearance from maximum anticipated groundwater levels. <br /> This groundwater clearance, as practical, should be three feet or more from known groundwater <br /> level. Soil Boring ground water elevation measurements indicate that this guideline has been met. <br /> Mottled soil as indicated in the Soil Boring Logs indicates seasonally saturated ground water levels <br /> near the existing ground surface. Subsurface drains could be installed to increase pavement life if the <br /> clients construction budget, existing topography and connections onto existing drainage structures <br /> make it practicable. <br /> 2. Pavement Section Thickness Designs <br /> The thickness of pavement section will depend on the type of material present within the <br /> upper portion of the subgrade. It is assumed that this subgrade material will consist of the existing <br /> clays or sand loams found on this site. In this report,we recommend the pavement design be based <br /> on an assumed R-value of 20, AASHTO Soil Type A-4 or Clays AASHTO A6. <br /> MATERIAL Section Thickness Section Thickness <br /> Car Parking Areas Roadway Areas <br /> Bituminous Wear (Type 41) 1 '/2" 1 ''/i" <br /> Bituminous Base (Type 31) 1 '/2" 1 '/z" <br /> Class 5 Aggregate Base (MnDOT 3138) 8" 8" <br /> Geo-fabric reinforcement* None Yes <br /> *Installed as per manufactures recommendation. <br /> 3. Limitations of Investigation <br /> The Geotechnical Engineer has prepared this report using an ordinary level of care and in <br /> accordance with generally accepted foundation and soil engineering practices. Because the <br /> borings represent only a small portion of the total site and for other reasons, SPC Engineering& <br /> Testing, Inc.,does not warrant that the borings are necessarily representative of the entire site but <br /> 3 <br />