Laserfiche WebLink
Pacific Ridge — DRH, LLC ES-7829.01 <br /> August 26, 2021 Page 7 <br /> Temporary Erosion Control <br /> The following temporary erosion control measures should be considered: <br /> • Temporary construction entrances and drive lanes, consisting of at least six inches of <br /> quarry spalls, should be considered to both minimize off-site soil tracking and provide <br /> stable surfaces at site entrances. Placing geotextile fabric underneath the quarry spalls <br /> will provide greater stability if needed. <br /> • Silt fencing should be placed around the appropriate portions of the site perimeter. <br /> • When not in use, soil stockpiles should be covered or otherwise protected to reduce the <br /> potential for soil erosion, especially during periods of wet weather. <br /> • Temporary measures for controlling surface water runoff, such as interceptor trenches, <br /> sumps, or interceptor swales, should be installed prior to beginning earthwork activities. <br /> • Dry soils disturbed during construction should be wetted to minimize dust and airborne soil <br /> erosion. <br /> • When appropriate, permanent planting or hydroseeding will help to stabilize site soils. <br /> Additional Best Management Practices, as specified by the project civil engineer and indicated <br /> on the plans, should be incorporated into construction activities. Temporary erosion control <br /> measures may be modified during construction as site conditions require, as approved by the site <br /> erosion control lead. <br /> Excavations and Slopes <br /> Based on the soil conditions observed at the subsurface exploration locations, excavation <br /> activities are likely to expose loose to medium dense existing fill and native soils within the upper <br /> 3 to 10 feet of existing grades, becoming dense to very dense at depth. The following Federal <br /> Occupation Safety and Health Administration and Washington Industrial Safety and Health Act <br /> soil classifications and maximum allowable temporary slope inclinations may be used: <br /> • Areas exposing groundwater seepage 11.51-11V (Type C) <br /> • Loose soil 1.51-1:1V (Type C) <br /> • Medium dense soil 1 H:1 V (Type B) <br /> • Dense to very dense "hardpan" native soil 0.75H:1 V (Type A) <br /> Earth Solutions NW, LLC <br />