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' August 13,2008 <br /> Project No.T-6241 <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 <br /> ' relatively impermeable sediment or bedrock. <br /> iii. Springs,groundwater seepage,or saturated soils. <br /> d. Anyarea which has shown movement duringthe Holocene epoch (from ten thousand years ago to the <br /> P Y g <br /> 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 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 /> 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. No site specific topographic information is available <br /> for our review; however, we estimate that the side slopes of the eastern portion of the site generally range from <br /> 25 to 40 percent and steeper in places. Based on our geologic data review and test pits excavated near the top of <br /> the slope, the slope is expected to be underlain primarily by Qva soils. Therefore, according to the criteria <br /> presented in item (b)(ii) and (a)(ii) above, the east slope would be considered a medium to high-risk landslide <br /> hazard area. <br /> ' As discussed, we did not observe indications of deep-seated instability or persistent groundwater seepage on or <br /> above the slope face, and much of the slope supports growth of relatively-straight mature coniferous trees. As <br /> ' previously mentioned, site development is shown to encroach no closer than 25 feet from the top of the on-site <br /> slope as well as the adjacent off-site slope further to the southeast. <br /> 1 <br /> 1 <br /> Page No. 5 <br /> i <br />