1228 GRAND AVE Geotech Report 2022-10-25

April 7,2008 Mr.Don Levin L&A Job No. 8A037 Page 8 areas. Unsupported temporary cuts greater than 4 feet in height should be no steeper than 1H:1V in the surficial topsoil and weak soils in the root zone, and no steeper than 1/2H:1 V in the underlying dense sand and/or hard silt soil layer. The soil units and the stability of cut slopes should be verified by a geotechnical engineer during excavation. The above recommended cut slopes are under the assumption that groundwater seepage would not be encountered during construction. If groundwater seepage is encountered, the construction should be immediately halted and the slope stability re-evaluated. The cut slopes may have to be flattened and other measures taken to stabilize the slopes. Surface runoff should not be allowed to flow uncontrolled over the top of cut slopes. Cut slopes should be covered with plastic tarps, as required,to protect them from erosion by stormwater. STRUCTURAL FILL Structural fill is the fill that support structural or traffic load. Structural fill should consist of clean soils with particles not larger than four inches and should be free of organic and other deleterious substances. Structural fill should have a moisture content within one percent of its optimum moisture content at the time of placement. The optimum moisture content is the water content in the soil that enable the soil to be compacted to the highest dry density for a given compaction effort. The on-site clean till soils may be used for structural fill only under fair weather conditions when their moisture content can be controlled to near optimum moisture content at the time of placement. Imported material to be used as structural fill, should be clean, free-draining, granular soils containing no more than 5 percent by weight finer than the No. 200 sieve based on the fraction of the material passing No. 4 sieve, and should have individual particles not larger than four inches. LIU & ASSOCIATES, INC.