5720 EAST DR 2018-01-02 MF Import

Geotechnical Engineering Report Parcel 00471700002401- 57XX East Drive Everett, Washington December 12, 2009 RMI File No. 53409 Page G Temporary and Permanent Slopes Temporary cut -slope stability is a function of many factors, such as the type and consistency of soils, depth of the cut, surcharge loads adjacent to the excavation, length of time a cut remains open, and the presence of surface or ground water. It is difficult under these variable conditions to estimate a stable, temporary, cut -slope angle. Therefore, it should be the responsibility of the contractor to maintain safe slope configurations since the contractor is continuously at the job site, able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and ground water conditions encountered. For planning purposes, Ave recommend that temporary cuts in the slope soils be no steeper than l Horizontal to I Vertical (IH: IV). If ground water were encountered, we would expect that flatter inclinations would be necessary. This information is provided solely for the benefit of the owner and other design consultants and should not be construed to imply that RMI ASSOCIATES LLC assumes responsibility for job site safely. The on -site contractor is the entity solely responsible for job site safety. We recommend that cut slopes be protected from erosion. Measures taken may include covering cut slopes with plastic sheeting and diverting surface runoff away from the top of cut slopes. We do not recommend vertical slopes for cuts deeper than 4 feet, if worker access is necessary. We recommend that cut slope heights and inclinations conform to WISHA/OSHA standards. Final slope inclinations for structural fill and cuts in the native soils should be no steeper than 2H: IV. Lightly compacted fills or common fills should be no steeper than 3H: IV. Common fills are defined as Fill materials, potentially with some organics, that are "trackrolled" into place. They would not meet the compaction specification of structural fill. Final slopes should be planted and covered with straw or jute netting. The vegetation should be maintained until it is established. Structural Fill General: All fill placed beneath buildings, pavements or other settlement -sensitive features should be placed as structural fill. For the purpose of this report, structural 1111 is defined as material that is placed in accordance with prescribed methods and standards, and is monitored by an experienced geotechnical professional or soils technician. Field monitoring procedures would include the performance of a RMI ASSOCIATES LLC I