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June 9,2022 <br /> Page 3 of 15 <br /> Geotechnical Evaluation <br /> The eastern portion of the site slopes downward from west to east at magnitudes of up to 100 <br /> percent and relief of about 12 feet.This portion of the site appears to have been previously graded. <br /> We observed the current site conditions and visually assessed adjacent steep slope areas during <br /> our site visit in April 2022. We did not observe evidence of severe erosion or instability in any of <br /> the areas. <br /> The following are code items with our comments underlined after the 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 /> 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 /> www.cobaltgeo.com (206)331-1097 <br />