6807 EVERGREEN WAY 2016-01-01 MF Import

GEOTECHNICAL ENGINEERING STUDY JMD Architecture April 19, 1999 Pavement Areas E-8689 Page 10 The adequacy of site paverc�ents 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 Genera/ Earthwork section of this report. This mer3ns at least the top twelve (12) inches of the subgrade should be compacted to 95 percent of the maximum dry density (per ASTM D-1557-78). It is possible that some localized areas of soft, wet or unstable subgrade may still e:cist after this process. 'fherefore, a greater thickness ef structural fill or cr�shed 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 (CRB1 material, or • Two inches of AC over three inches of asphalt treated base (ATB) material. We wili be pleased to assist in developing appropriate pavement sections for heavy traffic zones, if needed. Pavement materials should conform to WSDOT spacifications. The use of a Class B asphalt mix is suggested. LIMITATIONS Our recommendations and conclusions are based on the site materials observed, selective laboratory testing and engineering analyses, the design information provided us and our experience and engineeringjudgment. 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 expressed or implied. Erth Con�uh�nb. Inc.