8615 7TH AVE SE Geotech Report 2018-01-02 MF Import

Subsurface Exploration, Geologic Hazard, and St. Mary Magdalen Spoil Court Preliminary Geotecbnica.' Engineering Report Everett, Washington Preliminary!)esignRecommendations 11I. PRELIMINARY DESIGN RECOMMENDATIONS 7.0 INTRODUCTION Our exploration indicates that, from a geotechnical standpoint, the proposed project is compatible with this site provided the recommendations contained herein are properly followed. The bearing stratum is relatively shallow; therefore, we recommend the use of standard spread and continuous footings to support the new sport court structure. 8.0 SITE PREPARATION ISite preparation of building and pavement areas should include removal of all vegetation, existing pavement, debris, and any other deleterious materials. The existing fill soils should ! be removed from the area where the new structure is planned. After stripping, remaining roots and stumps should be removed from structural areas. Any depressions below planned final grades caused by stripping and grubbing operations should be backfilled with structural fill, as idiscussed under the Structural rill section. Once excavation to subgrade elevation is complete, any soft, loose, or yielding areas should be excavated to expose suitable bearing soils. The subgrade should then be compacted to a firm and unyielding condition. Structural fill can then be placed to achieve desired grades, if needed. 8.1 Temporary Cut Slopes In our opinion, stable construction slopes should be the responsibility of the contractor and should be determined during construction. Current design plans call for the use of temporary cut slopes ranging less than a depth of 3 feet. If cuts extend deeper than 4 feet, the fill soils should be maintained at 1.5FI:1V (Hoiizontal:Vertical), and cuts into the dense till soils may approach 3/4H:1V. Ilowever, these slope angles could be adjusted in the field when the cuts are opened up. 8.2 Site Disturbance Most of the on -site soils contain substantial fine-grained material. which makes them moisture - sensitive and subject to disturbance when wet. The contractor must use care during site preparation and excavation operations so that the underlying soils are not softened. If April 24, 2006 ASSOCIATED EARTH SCIL"CES, INC. R1PQ4-KEa 2WAI-Pro/ettt12WW26MKE1NP Page 8