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Crow-Western E-27U8 <br />Au9ust 14, 1985 Paye 7 <br />All permanently exposed slopes should be seeded with an <br />appropriate species of ve��etation to reduce erosion and improve <br />stal�ility of. the surEicial ]ayer of soil. <br />Site Draina9e <br />It has been our experience that gcro undwaCer levels change <br />significantly due to changes in rainEall amounts, surface drainage <br />or other factors. If seepage is encountered in the excavation, <br />the water should be drained away from the site by use of drainage <br />ditches, perEorated pipe or French drains, or by pumping from <br />sumps interconnected by shallow connector trenches at the bottom <br />of the excavation. <br />We suggest that appro�riate locations of subsurface drains, if <br />needed, be established during grading operations by a represen- <br />tative of Earth Consultants, Inc., at which Cime the seepage <br />areas, if present, may be more clearly defined. <br />The excavation and site should be yraded so that surface water <br />is directed off the site and away from the tups of slopes. Water <br />should not be allowed to stand in any area where buildings, slahs, <br />or pavements are to be constructed. During construction, loose <br />surEaces should he sealed at night by compacting the surEace soils <br />to reduce the inEiltration of rain into the soils. Final site <br />grades should allow for drainaye away from the huilding founda- <br />tions. We suggest that the ground be slope�9 3 percent for a <br />distance of at least ten feet away from the buildin9s except in <br />areas thaC are to be paved. <br />Pavement Areas <br />All parking and roadway areas may be supportad on native soils <br />or existing fills provided these soils can he compacted to 95 <br />percent density and are stable at the time oE construction. <br />Structural fill and or Eabric may be needed to stabilize soft, wet <br />or unstable areas. In most instances twelve (12) inches of <br />granular fill will stabilize the s�bgrade except for very soft <br />areas where additional fill could be required. The upper twelve <br />(12) inches of pavement subgradc should be compacted to at least <br />95 percent oE the maximum c9ensity. Below this level a compactive <br />eEfort oE 90 ��ercent would be adequate. The pavement section for <br />lightly loaded trafEic and parking areas should consist of two <br />inches of asphalt concrete (AC) over four inches of crusheci rock <br />base (CRB) or ttiree inches of asphalt treated base (ATN). Heavier <br />loaded areas would require thicker sections. We will be pleased <br />to assist you in developing appropriate pavement sections or <br />specifications Eor heavy traEfic zones, if needed. <br />Eanh Consuhants, Inc <br />