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February 22,2016 <br /> Project No.T-7364 <br /> b. Those areas defined as medium risk of erosion in the Dames and Moore Methodology for the Inventory, <br /> Classification and Designation of Geologically Hazardous Areas,City of Everett, Washington:July 1, 1991, <br /> when they contain debris and mud flows,gullying or rifling, immature vegetation, or no vegetation: <br /> i. Slopes of 25 to 40 percent in other(not Qva or Qal)geologic units. <br /> As discussed,we did not observe indications of erosion at the site with the exception of channel erosion along the <br /> axis of the drainage ravine. In our opinion, conditions meeting the criteria given above for high and very high <br /> risk of erosion do not exist at the site. Considering that the inclination along the axis of the drainage channel is <br /> about seven to ten percent, and that the ravine sideslopes are generally vegetated with mature trees and brush <br /> with a well-developed layer of forest duff on the ground surface, it is our opinion that conditions meeting the <br /> above criteria defining a medium risk of erosion do not exist at the site. <br /> 3.4.2 Landslide Hazard Areas <br /> Chapter 37.080.1 of the EMC defines landslide hazard areas as follows: <br /> a. Those areas defined as high and very high/severe risk of landslide hazard in the Dames and Moore <br /> Methodology for the Inventory, Classification and Designation of Geologically Hazardous Areas,City of <br /> Everett, Washington: July 1, 1991: <br /> i. Very high/severe: slopes greater than 15 percent in the'Qtb, Qw, and Qls geologic units;and slopes <br /> greater than 15 percent with uncontrolled fill. <br /> ii. High: slopes greater than 40 percent in all other geologic units(not Qtb, Qw, and Qls or uncontrolled <br /> fill). <br /> b. Those areas defined as medium risk of landslide hazard in the Dames and Moore Methodology for Inventory, <br /> Classification and Designation of Geologically Hazardous Areas, City of Everett, Washington: July 1, 1991, <br /> when combined with springs or seeps, immature vegetation,and/or no vegetation: <br /> i. Slopes less than 15 percent for Qtb,Qw,and Qls geologic units and uncontrolled fill. <br /> ii. Slopes of 25 percent to 40 percent in all other geologic units. <br /> c. Any area with all three of the following characteristics: <br /> i. Slopes greater than 15 percent. <br /> ii. Hillsides intersecting geologic contacts with a relatively permeable sediment overlying a relatively <br /> impermeable sediment or bedrock. <br /> iii. Springs,groundwater seepage,or saturated soils. <br /> Page No.4 <br />