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June 23, 2014 <br /> Project No. T-6241 <br /> d. Any area which has shown movement during the Holocene epoch(from 10,000 years ago to the present) <br /> or which is underlain or covered by mass wastage debris of that epoch. <br /> e. Any area potentially unstable as a result of rapid stream incision,stream bank erosion, or undercutting by <br /> wave action. <br /> f. Areas of historic failures, including areas of unstable, old and recent landslides or landslide debris within <br /> a head scarp, and areas exhibiting geomorphological features indicative of past slope failure, such as <br /> hummocky ground, slumps, earthflows,mudflows,etc. <br /> g. Any area with a slope of 40 percent or steeper and with a vertical relief of 15 or more feet, except <br /> those manmade slopes created under the design and inspection of a geotechnical professional, or slopes <br /> composed of consolidated rock. <br /> h. Areas that are at risk of landslide due to high seismic hazard. <br /> i. Areas that are at risk of landslides or mass movement due to severe erosion hazards. <br /> The City of Everett Landslide Hazard,Critical Areas Map 2,dated March 2006,shows the eastern extreme of the <br /> site is within or adjacent a medium landslide hazard area. Based on the site topography available, we estimate <br /> that the side slopes of the eastern portion of the site generally range from 20 to 55 percent. Based on our <br /> geologic data review and test pits excavated near the top of the slope, the slope is expected to be underlain <br /> primarily by Qva soils. Therefore, according to the criteria presented in item (b)(ii) and (a)(ii) above, the east <br /> slope would be considered a medium to high-risk landslide hazard area. <br /> As discussed, we did not observe indications of deep-seated instability or persistent groundwater seepage on or <br /> below the slope face, and much of the slope supports growth of relatively-straight mature coniferous trees. Based <br /> on review of the PacLand plans, grading to establish development elevations adjacent the eastern boundary will <br /> be setback a minimum of 50 feet from the steeper 40 percent slopes. With this setback and development runoff <br /> controlled and not allowed to flow over the eastern slopes the development will have no impact on the current <br /> slope stability. <br /> 4.3 Seismic Hazard <br /> Section 37.080(A)(2)of the EMC defines seismic hazard areas as: <br /> a. Those areas mapped as seismic/liquefaction hazards per the Dames and Moore Methodology for the <br /> Inventory,Classification and Designation of Geologically Hazardous Areas,City of Everett,Washington: <br /> July 1, 1991. <br /> b. Those areas mapped as high and moderate to high liquefaction susceptibility on the Liquefaction <br /> Susceptibility Map of Snohomish County, Washington, Washington State Department of Natural <br /> Resources,Palmer, Stephen, et al., September,2004. <br /> Page No. 5 <br />