5302 SOUND AVE 2016-01-01 MF Import

CFSCRDE GEOTECHIvICRL TEL�206-520-6953 Rug 05,94 �_ CASCADE GEOTE�F��JICAL INC. August S, 1994 S.0 CONCLUSIONS AND RECOMMENDATIONS Job No. 9407-04G We conclude that the undisrorbed native soils observed in this area arc well suited for foundinQ of li�ht structures. These undisturbcd native soils should generally produce stable slopes and the undistutbed, dense, native soil slopes are suitable for development if adequate subsurface dcainaee and emsion wnuol m�:sures ue implemented. We believe that the northern portion of the home was not founded on undiswrbed nadve �oils or properly compacted structural fi11• It spPears that the subgrade soils were derived from the oti�inal lot levellin� cut and probably some importe� fill as well, and that this fill was placed •in m unoompactod condition. It is doabtful that any subsudace preparadon prior to plaament of the fill was made, or that any subsurface drainage was provided. Due W the damage caused by founding of the exisdng residence founda6on perimeter on unsuitable wils, we conclude that the northem, and norih end of the east and west foundadon perimeters of the existing structure should be undapinned at once and corrxdve measures ' �ndertai�en promptly W stabiGu the slope. The uncontrolled fill found on site is not suitable for tupportin� the exisung spread foo6ng foundations since the unacceptable differartial settlements of the suucture will condnue. Our DCPT results indicate that a substandal thiclrness of fill is present on the slope. It dso appears that the original topography of this area was quite steep. Based on our observations, we conclude that the fill slope has experienced slumping and erosion in the past. The slope is currently barely stable and might nmain so for a dme if protected from infiltration and erosion from surface water. Permanent stabilization of this slope will require extensive work. The analysis of this slope was beyond our scope of work for providtng underpinning 7