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Veritas Construction Inc ES-4011.03 <br /> June 17, 2016 Page 6 <br /> Revised June 22, 2016 <br /> Landslide Hazard <br /> According to EMC 38.080(A)(1), landslide hazard areas are defined as: <br /> • Those areas defined as high and very high/severe risk of landslide hazard in the Dames <br /> and Moore Methodology for the Inventory, Classification and Designation or Geologically <br /> Hazardous Areas, City of Everett, Washington, July 1, 1991; <br /> o Very High/Severe: Slopes greater than 15 percent in the Qtb, Qw, and Qls <br /> geologic units; and slopes greater than 15 percent with uncontrolled fill; <br /> o High: Slopes greater than 40 percent in all other geologic units (not Qtb, Qw, and <br /> Qls or uncontrolled fill); <br /> • Those areas defined as medium risk of landslide hazard in the Dames and Moore <br /> Methodology for the Inventory, Classification and Designation or Geologically Hazardous <br /> Areas, City of Everett, Washington, July 1, 1991, when combined with springs or seeps, <br /> immature vegetation, and/or no vegetation; <br /> o Slopes less than 15 percent for Qtb, Qw, and Qls geologic units and uncontrolled <br /> fill; <br /> o Slopes of 25 to 40 percent in all other geologic units; <br /> • Any area with all three of the following characteristics: <br /> o Slopes greater than 15 percent; <br /> o Hillsides intersecting geologic contacts with the relatively permeable sediment <br /> overlaying a relatively impermeable sediment or bedrock; <br /> o Springs, groundwater seepage, or saturated soils. <br /> • Any area which has shown movement during the Holocene epoch (from ten thousand <br /> years ago to the present) or which is underlain or covered by mass wastage debris of <br /> that epoch; <br /> • Any area potentially unstable as a result or rapid stream incision, stream bank erosion or <br /> undercutting by wave action; <br /> • Areas of historic failures, including areas of unstable, old and recent landslides or <br /> landslide debris within a head scarp, and areas exhibiting geomorphological features <br /> indicative of past slope failure, such as hummocky ground, slumps, earthflows, <br /> mudflows, etc; <br /> • Any area with a slope of forty percent or steeper and with a vertical relief of fifteen or <br /> more feet, except those manmade slopes created under the design and inspection of a <br /> geotechnical professional, or slopes composed of consolidated rock; <br /> • Areas that are at risk of landslide due to high seismic hazard; <br /> • Areas that are at risk of landslides or mass movement due to severe erosion hazards. <br /> Earth Solutions NW,LLC <br />