Report of Geotechnical Investigation

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i . Iincrease near-surface densi of s ty urfaces. Soil correct exposed natural ground along foundation ( bearing grades that is not suitable or not reliable to support foundations, based on engineering inspection of exposed soil and recommendations for correction. Natural soil prepared as described herein should be reliable to support foundations. I RECOMMENDATIONS I SITE PREPARATION I Project design and site preparation may require abandonment or �elocation of buried utilities, including utilities discovered during construction. Utilities must be completely removed, capped, or fully grouted. Utility excavation must be filled according to the OVER-EXCAVATION AND ' STRUCTURAL BACKFILL section of this report. Site preparation may require demolition and complete removal of all subsurface building components, including components discovered during construction (foundations and foundation walls, floor slabs, septic systems). Existing pavement designated for removal, including pavement discovered during construction, must be removed completely to expose and remove underlying voids that can potentially trap water. EXCAVATION AND EARTHWORK CLEARING AND GRUBBING Clearing and grubbing must remove all trees, brush, stumps, roots, and designated removal structures within clearing limits. Stump holes and removed structures should be replaced with structural backfill to prevent localized subsidence in planned construction areas. TOPSOIL REMOVAL AND REUSE All natural tbpsoil, replacement topsoil and buried topsoil (all with undecomposed organic matter) must be completely stripped away and removed from project areas designated for construction. These organic bearing soils must not remain beneath buildings and other structures, pavements (including roads, driveways and sidewalks) and structural fiil or structural backfill. These soils can potentially decay when they are exposed to bacteria and oxygen (air), which may cause excessive ground surface subsidence beneath the above built features during their lives. These soils can be reused as topsoil replacement in designated ' landscape areas, wasted onsite, or exported offsite. Natural topsoil (typically) may extend 6 to 18 inches deep from the ground surface and contain grass, roots, decaying vegetation, humus and undecomposed organic matter, all with faint to strong organic odor. Thickness of natural topsoil may vary across the site. It may be significantly thicker in low-lying areas where it has slowly accumulated as colluvial slope-wash. Boring Logs note roughly estimated and generalized topsoil thickness at bored locations. To accurately determine topsoil thickness and quantity, observation test pits should be made wi#h a backhoe or hand shovel across the project site area. Allied Projed 05039 7 July 31, 2005