4728 COMMERCIAL AVE 2016-01-01 MF Import

• i 1 Rohcrt Kincaid June 27, 2007 Pagc 3 along thc stccp;lopc bchveen the site and the Interuban'Crail during our site reconnaissance. No evidence of surfacc watcr runoff or crosion was obscrved within the site or adjacent areas. No evidence of slope instcibility �vas obscrved within thc site or adjacent areas; discussions with a nciahbor who has lived near the site for more than 40 years con[irnicd that no landslides havc occurred wi�hin or adjaccnt to thc sitc during tha[ time. CONCLUSIONS AND RECOMMENDATIONS GENERAL [t is om� opinion that thc property is suitable for thc proposed residential dcvclopmcnt provided that proper site development proccdures arc followed,�ncluding thc recommended sctback buffer from thc top of thc stcep slope along thc castern tnargin of the sitc. Thc nativc soils underlying the site consist of mcdium densc to dcnse glacial outwash sand, and arc suitabic for convcntional residential foundation design and construction proccdures. CRITICAL AREAS Thc stcep slope within and ad.jaccni to thc castcrn part oP the site, which was crcatcd during gracting for the Intenu'ban Raih��ay approximatcly 100 ycars ago, is stceper than 40 percent .md is underlain by glacial advancc outwash sand (Qvs), and it thercforc meets the City of 6verett criteria for a geologically hazardous area, both as a landslide haznrd arca and an erosion hazard arca. The top of thc d0 percent slopc is shown on Figw�c Z. As describcd above,this stccp slope is widerlain by dcnse glacial advance outwash sand,and no uvidence ol' groundwatcr scepage or slopc instability was obscrvcd within or adjacent to the site. Based on thc inclination of the slope and thc charactcr of the soils underlying thc slopc it is our opinion that this stcep slope is presendy staUle, but that it is susceptible to erosion or shallow debris slides if disturbed by construclion or other activities. To provide an adcquate margin adjaccnt to the proposed residence in the event diat crosion or shallosv dcbris sliding occurs �vithin thc steep slopc area, we recommend a building setback buPfer of 25 feet Crom die rop of the 40 percent slope. The top of this setbach buffer is shown on Figure 2. No carth�vork should be performed widiin the area of d�e setback buffcr,except that Ihc stcep face of the cxistina fill soils within that arca should be regraded to a 31-I:1 V slope. Dis[urbcd areas within the setback buffcr should be rr,planted using native and/or other low-tnaintenancc vcgctation. It is our opinion that thc recotnmended setback buffer, together ��i[h appropriate conshvclion procedures, proper drainagc and crosion coriu•ols, and revegetation, will adcquatcly protect both the proposed � dcvclopment and thc critical area. / 3 �� 7505 West L;�ke Sammamish Porkway Northeast Redmond,Washington 98052 425-882-0850 w�wl.lUbbs.com ��