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FEB 7, 2018 RESUB GEOTECH LETTER.pdfRobert M. Pride LLC Consulting Engineer January 22, 2oi8 Mr. Joe Lucia, P. E. Structural Engineer 7307 12th Avenue NE Seattle, WA 98115 Re: Geotechnical Plan Review Proposed Residence — Lots i and 2 18109/111 84th Avenue West Edmonds Washington Permit #BLD2017017 Dear Mr. Lucia, This report confirms that I have reviewed the final structural plans for the two proposed residences on Lots 1 and 2 located on the east side of 84th Avenue East in Edmonds. These plans were based on our geotechnical recommendations provided in report, and the structural plans dated November 2017 were prepared by Lucia Engineering. Temporary slope cuts will be made with the upper sections excavated down at a 1H:1V slope and then vertical below. These slope cuts will expose dense glacial outwash soils that consist of silty sands and gravel that will stand without instability during construction of these two residences. Evaluation of the slope stability for these temporary slope cuts shows they will have a factor of safety in excess of 1.5 for static and 1.2 for seismic conditions, and will provide construction safety during installation of the adjacent foundations and retaining walls. It is recommended that these slopes be covered with heavy plastic sheeting for protection during the wet season months. As requested by the city of Edmonds these temporary slope cuts will not adversely impact the adjacent residential structure or other nearby critical areas. In my opinion there will not be any hazards created that will be in excess of the existing pre - development conditions. Locations of the two structures on Lots 1 and 2 will have a sufficient setback from steep slopes and there will; be no risk for landslide development or risk to these new residential structures. No steep slopes will exist upon completion of these residences when final retaining wall backfill has been properly placed and compacted. in A minimum ten foot buffer should be acceptable for structure protection where any steep slopes exist upon final site grading. On the basis of my final plan review of the Lucia drawings for this project, they are satisfactory from a geotechnical point of view, and they are in accordance with our recommendations in our November 10, 2017 report. We will provide the required Robert M. Pride, LLC Page 1 13203 Holmes Point Drive NE Kirkland, WA 98034 geotechnical inspections as required by the city of Edmonds, and appropriate field memos will be prepared for submittal to the city. Please call me if there are any questions. Respectfully, wa sN,N� `CJ �r 4 �0 y �o 1 fi 71 SS�ONM- EaG Robert M. Pride, P. E. Principal Geotechnical Engineer dist: (1) Addressee rmp: Lucia84thRes4 Robert M. Pride, LLC Page 2 13203 Holmes Point Drive NE Kirkland, WA 98034