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December 14, 2020 <br />Page 2 of 6 <br />Limited Geologic Evaluation <br />We observed the current site conditions and visually assessed adjacent steep slope areas during <br />our site visit on December 10, 2020. We did not observe evidence of severe erosion or instability <br />in any of the areas. All areas observed appear stable at this time. Limited erosion was observed; <br />however, proper implementation of erosion control devices should adequately limit erosion on <br />the property during construction. <br />We understand that there are erosion and steep slope/landslide hazard areas within the property <br />and on adjacent properties. The following are code items with our comments underlined after the <br />relevant sections. <br />A. Designation. The following geologically hazardous areas shall not be altered except as <br />otherwise provided by this chapter: <br />1. Landslide hazard areas: <br />a. Those areas defined as high and very high/severe risk of landslide hazard in the Dames and <br />Moore Methodology for the Inventory, Classification and Designation of Geologically Hazardous <br />Areas, City of Everett, Washington: July 1, 1991, or as revised through best available science: <br />(1) Very high/severe: slopes greater than fifteen percent in the Qtb, Qw, and Qls geologic units; <br />and slopes greater than fifteen percent with uncontrolled fill. <br />(2) High: slopes greater than forty percent in all other geologic units (not Qtb, Qw, and Qls or <br />uncontrolled fill). <br />b. Those areas defined as medium risk of landslide hazard in the Dames and Moore <br />Methodology for Inventory, Classification and Designation of Geologically Hazardous Areas, City <br />of Everett, Washington: July 1, 1991, or as revised through best available science, when combined <br />with springs or seeps, immature vegetation, and/or no vegetation: <br />(1) Slopes less than fifteen percent for Qtb, Qw, and Qls geologic units and uncontrolled fill. <br />(2) Slopes of twenty-five percent to forty percent in all other geologic units. <br />c. Any area with all three of the following characteristics: <br />(1) Slopes greater than fifteen percent; and <br />(2) Hillsides intersecting geologic contacts with a relatively permeable sediment overlying a <br />relatively impermeable sediment or bedrock; and <br />(3) Springs, ground water seepage, or saturated soils. <br />d. Any area which has shown movement during the Holocene epoch (from ten thousand years <br />ago to the present) 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 <br />undercutting by wave action. <br />f. Areas of historic failures, including areas of unstable, old and <br />recent landslides or landslide debris within a head scarp, and areas exhibiting geomorphological <br />features indicative of past slope failure, such as hummocky ground, slumps, earthflows, <br />mudflows, etc. <br />g. Any area with a slope of forty percent or steeper and with a vertical relief of fifteen or more <br />feet, except those manmade slopes created under the design and inspection of a geotechnical <br />professional, or slopes composed of consolidated rock. <br />www.cobaltgeo.com (2o6) 331-1097 <br />