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Grosion H�ard <br /> The onsitc soils in thc devclopment arca have a modcratc erosion potential due to ihe slopc of the <br /> topography. "I�he proper use of"best management pr.actices" I3MPs should be used during <br /> dcvclopment of thc rcsidences to minimize Uie pote�rtial for erosion and scdiment transport. Thc <br /> following is a partial list of IIMPs lhat should bc implemcntcd. <br /> • Rock conswction entrancc <br /> • Silt fcna: across thc west sidc of thc clearing arca <br /> • Keeping all exposed soils arvereci when not activcly �+urkcd <br /> • Scheduling earth work activities during dry conditions <br /> • Fstablish tcmporary/pertnancnt vcgcL{tion ns soon as possibic a�icr foundation <br /> installation a��1 utility hook-up. <br /> With proper implcmcntatiun oCbcst man�cmcnt practiccs :uid common �cnsc (i.c. don't start <br /> excavating Uic foundation in ehc middlc a forccasted large rein cvcnt), thc pro�crty ma}• bc <br /> dcvclupcd wilhout significant crosion or scdiment transport. <br /> ticism�c Haz.vd <br /> Generally, therc ane four lyj�es of potential gcologic ha�:irds assucia�cd wiUi largc scismic <br /> cvents: I) surficial ground rupture; 2) scismically inJuced landslid�s; 3) liyucfaction; and 4) <br /> gmund motion. "17�e polcntial for cach of il�cse to unpact thc sitc is discussed below. <br /> lhc sitc was not undcrlain by a known fault zonc. Pault zoncs in Uie Pugct Sound rcgiun arc <br /> currently bcing swdicd by the Uniteci States Gcological Scrvicc (USGS) and have becn <br /> determined to be active and capable of producing large earthquakes. Much is still to be lecuned <br /> about these fault systcros but it is gcnerally hy7�othesized that their recurrcncc intcrval is scvcral <br /> Iho�saod ycars. Duc to thc saspcctui long rccurrcncc intcrval and the unccrtainty of whcrc thc <br /> ncxt surface rupturc may occur,the �x�tenlial for surfici:il f;round rupturc is considered to bc <br /> unprcdictablc and no mitigation is possible or nccessary. <br /> 1)ue to lhc lack of advcnc �mund watcr conditions and t]ic high intcrnal strcngth of Uic dcnsc <br /> advance outwash scdimm�lt within the slo�n, Uic risk uf a rutational landslide is considered �o hc <br /> lo�i�. <br /> BascJ un Uic Jcnsc cunJitiun of thc scdimcnts cucuuntcrrJ iu our c�plur�tion pits anJ thc lack <br /> of advcrsc graund w:itcr conJitions, it is our opiuion that the risk of liyucfaction on tliis silc is <br /> IJW. <br /> Seismic haj�rds that will affect thc house will be due to the intensity:u�d duration of the ground <br /> shaking. I3ascd on Qic cna�untcrccl stratigraphy, strvctural design of thc projcct should bc <br /> consistcnt with 2003 /rrfcrnntinnnl Xr�ildin��Code QI3C) guidclincs. In accorciancc with 7'ablc <br /> 1h15.1.1 of�hc 2003 1[3C, ilic subjcct silc wotdd bc cla5si(icd as Site Clttss C. <br /> IIGC,pllc 14267 209'h Avcnuc NE, Woodinville, WA 98077 (425)273-5062 <br />