09 ATTACHMENTS - Laserfiche WebLink

C CORNERSTONE EARTH GROUP the owner's option the surface vegetation may be mowed, leaving no more than 1 inch of stubble, the area disked in two directions to a depth of 12 inches, moisture conditioned, and re- compacted (not applicable in undocumented fill areas). 6.1.2 Tree and Shrub Removal Trees and/or shrubs designated for removal should have the rootballs and any roots greater than''/z-inch diameter removed completely. Grade depressions resulting from rootball removal should be cleaned of loose material and backfilled in accordance with the recommendations in the "Compaction" section of this report. 6.1.3 Abandonment of Existing Utilities All utilities should be completely removed from within planned building areas. For any utility line to be considered acceptable to remain within building areas, the utility line must be completely backfilled with grout orsand-cement slurry (sand slurry is not acceptable), the ends outside the building area capped with concrete, and the trench fills either removed and replaced as engineered fill with the trench side slopes flattened to at least 1:1, or the trench fills are determined not to be a risk to the structure. The assessment of the level of risk posed by the particular utility line will determine whether the utility may be abandoned in place or needs to be completely removed. The contractor should assume that all utilities will be removed from within building areas unless provided written confirmation from both the owner and the geotechnical engineer. Utilities extending beyond the building area may be abandoned in place provided the ends are plugged with concrete, they do not conflict with planned improvements, and that the trench fills do not pose significant risk to the planned surface improvements. The risks associated with abandoning utilities in place include the potential for future differential settlement of existing trench fills, and/or partial collapse and potential ground loss into utility lines that are not completely filled with grout. The risk for each issue are relatively low for single utility lines less than 4 inches in diameter and increase with increasing pipe diameter. 6.2 REMOVAL OF EXISTING FILLS All undocumented fills, including soil stockpiles, should be completely removed from within building areas and to a lateral distance of at least 5 feet beyond the development area. Provided the fills meet the "Material for Fill" requirements below, the fills may be reused when backfilling the excavations. Based on review of the samples collected from our borings, it appears that the fill may be reused. If materials are encountered that do not meet the requirements, such as debris, wood or trash, those materials should screened out of the remaining material and removed from the site. Backfill of excavations should be placed in lifts and compacted in accordance with the "Compaction" section below. Ponderosa Active Adult Community Page 12 132-2-1