9205 4TH AVE W 2025-12-03 - Laserfiche WebLink

July 2, 2008 Duplex Buildings L&A Job No. 8AO67 Page 9 EXCAVATION AND FILL SLOPES Under no circumstance should excavation slopes be steeper than the limits specified by local, state and federal safety regulations if workers have to perform construction work in excavated areas. Unsupported temporary cuts greater than 4 feet in height should be no steeper than 1H:1 V in fill, topsoil and loose to medium -dense weathered soils and may be vertical in very -dense fresh till and dense advance outwash soils if the overall depth of cut does not exceed 10 feet. Otherwise, cut in fresh till and advance outwash soils should be no steeper than 3/4H:1V. Permanent cut banks should be no steeper than 211:1 V in fill, topsoil and weathered till soils and no steeper than 1-3/4H:1V in the very -dense fresh till and dense advance outwash soils. The soil units and the stability of cut slopes should be observed and verified by a geotechnical engineer during excavation. Permanent fill embankments required to support structural load should be constructed with compacted structural fill placed over proof -rolled, undisturbed, firm, fresh till or advance outwash soils after the unsuitable surficial soils are stripped. The slope of permanent fill embankments should be no steeper than 2H:1 V. Upon completion, the sloping face of permanent fill embankments should be thoroughly compacted to a non -yielding state with a hoe -pack. The above recommended cut and fill slopes are under the assumption that groundwater seepage would not be encountered during construction. If groundwater is encountered, the construction work should be immediately halted and the slope stability re-evaluated. The slopes may have to be flattened and other measures taken to stabilize the slopes. Stormwater should not allowed to flow uncontrolled over cut and fill slopes. Permanent cut slopes or fill embankments should be seeded and vegetated as soon as possible for erosion protection and long-term stability, and should be covered with clear plastic sheets, as required, to protect them from erosion until the vegetation is fully established. LIU & ASSOCIATES, INC.