881 OLYMPIC BLVD Geotech Report 2023-12-29

JWy M, 2023 Pn9c3vf6 t.im1Mtl GcutecM1Wcal NvWna lan b. Those areas defined as medium risk oflandslidehazard in the Dames mid Moore Methodology for Inventory, Classification and Designation of Geologically Hazardous Areas, City of Everett, Washington: July is 199a, or as revised through best available science, when combined with springs or seeps, bnmature vegetation, and/or no vegetation: (H Slopes less than fifteen percent for Qth,Qw, and Qls geologic units anduncontmlled fill. (2) Slopes of twenty-five percent forty percent in all other geologic units. a Any area with all three of the following characteristics: (Q Slopes gr'eaterthan fifteen percent; and (2) Hillsides intersecting geologic contacts with a relatively permeable sediment overlying a relatively impermeable sediment or bedrock; and (3) Springs,groundwaterseepage,orsaturatedsofls. d. Any area which has shown movement during the Holocene epoch (from ten thousand years ago to the present) or which is underlain or covered by mass wastage debris ofthat epoch. e. Any area potentially unstable as a result of rapid stream incision, shares bank erosion or undercutting by wave actioa E Areas of historic failures, including areas of unstable, old and recent landslides or landslide debris within a head scarp, and areas exhibiting geomonphological features indicative of past slope failure, such as hummocky ground, slumps, earthfloves, mudflows, etc. g. Any area with a slope of forty percent or steeper and with a ventral relief of fifteen or more feet, except those manmade slopes created under the design and inspection of a geotechnical professional, or'slopes composed of consolidated rock. It. Areas that are atrsk eflandslide dueto high seismic hazard. i. Areas that are at riskoflandslides or mass movement due to severe erosion hazards. Hazard amps M tzgt mosent JU the f the 'd d' t shallow undulating Areas that meet the 't hi bH ght d above are present at the top of the st LIORe am d critical area boundarv. We notethat the alcep &Igtbefurther t would meet the criteria of very hi h landslide heard areas along mdLh unsd f the other criteria noted abam This likely nd la' by y h and nw and epx w «. Lave eaoerienced landslide activity within the Holom a coach. 3. Erosion hazard areas: a. Those areas defined as high end very high/severe risk of erosion in the Dames and Moore Methodology for the inventory, Classification and Designation of Geologically Hazardous Areas, City of Everett, Washington: July 1, 1991, or as revised through best available science: (H High erosion hazard areas include slopes of twenty-five to forty percent in Qva and Qal geologic units; and slopes of greater than forty percent in other (not Qva or Qal) geologic units. (2) Very bigh/severe erosion hazard areas include slopes of greater than forty percent in Qva and Qal geologic units. baltg eon (2o6)331-vo97