1910 MERRILL CREEK PKY 2018-11-15

Intracorp E-3592-520 September 23, 1998 Page 9 Pavement Areas The adequacy of site pavements is related in part to the condition of the underlying subgrade. To provide a properly prepared subgrade for pavements, the subgrade should be treated and prepared as described in the Site Preparation and General Earthwork section of this report. This means at least the top twelve �12) inches of the subgrade should be compacted to 95 percent of the maximum dry density (per ASTM D-1557-91). It is possible that some localized areas of soft, wet or unstabfe subgrade may still exist after this process. Overexcavation and replacement with structural fill or crushed rock may be needed to stabilize these localized areas. The following pavement section for lightly-loaded areas can be used: • Two inches of asphalt concrete (AC) over four inches of crushed rock base (CRB) material, or • Two inches of AC over three inches of asphalt treated base (ATB► material, Heavier truck-traffic areas will require thicker sections depending upon site usage, pavement life and site traffic. In our opinion, the following pavement sections can be used for truck- trafficked areas: � Three inches of AC over six inches of CRB, or • Three inches of AC over four and one-half inches of ATB, All pavement materials should conform to WSDOT specifications. A Class B asphalt mix should be used. LIMITATIONS Our recommendations and conclusions are based on the observed site materials, selective laboratory testing and engineering analyses, the design information provided us, and our experience and engineering judgment. The conclusions and recommendations are professional opinions derived in a manner consistent with that level of care and skill ordinarily exercised by other members of the profession currently practicing under similar conditions in this area. No warranty is exp�essed or implied. The recommendations submitted in this report are based upon the data obtained from the test pits. Soil and groundwater conditions between test pits may vary from those encountered. The nature and extent of variations between our exploratory locations may not become evident until construction. If variations do appear, ECI should be requested to reevaluate the recommendations of this report and to modify or verify them in writing prior to proceeding with the construction. Earth Consultants, Inc.