5000 SEAHURST AVE 2016-01-01 MF Import

Mikc Vancc � � April 9 2004 Pagc 4 CONCLUSIONS AND RECOMMENDATIONS GEOLOGIC HAZARD CONSIDERATIONS General Portions of the site qualify as geologically hazarduus in accordancc with the definitions in the Ciry of Everett Lnvironmentally Sensiti��e Arcas Ordinance. These aicas are slopes of 40 percent or greater and crosion hazard arcas. Also, two of thrcc critcria which form a portion of landslide hazard areas are present. Thesc are (1) slopcs greatcr Ihan 15 percem, and (2) impermerble soils frequently interbedded with granular soils. Wc did not observe evidence of landslidc activity. We did not observe evidence of thc third criteria; springs, ground water seepage or saturatcd soils cmerging on the slopes. As prcviously diswsscd, minor landslide activities may be prescnt during a severe winter season when the underlying advancc outwash soils on the slope face wealhcr and undcrtnin:upper sections of glacial till. I3ecausc lhc sitc is not undcrlain by liyucfiablc soils Qoosc, cohcsionlcss soils in association with a shallow ground water table), the site docs not qualify as a scisr,iic hazard area. It is our opinian that specific construction mcthoJs consisting o(deep foundations, erosion control and drainage enha�cements can be utili�ed at the site to mitigate thc hazards of concem (steep slopes, erosion and minor landslidc hazards). Poundation, crosion and drainagc mitigation mcasures are discussed in dctail in following scctions. RECOMMENDED MITIGATION MEASURES General Spccific construction mcthods and drainagc cnhanccmcnt mcasures must bc utilizcd at the sitc to mitigatc steep slope and crosion hazards at the sitc. 'I'hese must hc implcmented to respond ro several crilcria as dcfincd in scction 37.030 of'fillc 19. Critcria with respcct to geologi: issucs that must bc salisficd includc: • 'I'hc dcaclopmcnt musl not crcalc a ha�ard lo thc property or surrounding propertics or crosion to off-si�c propertics or bodics of n�atcr, • Gcological constraints must hc addresscd including an assessmcnt of soils and hydrology, • 'I'hc construction should reducc crosion potcnlial, landslidc and scismic hazard potential, and will nol advc�scly afl'cct tlic slabilily uf slopcs, • l�hc proposal shuuld usc construcliun tcehniq�rs �vhich minimizc disruption of cxisting topoo:aphy and natural vcgctation. Gcologic conditions and surfacc hydrology arc discussed in this rcporl It is our opinion that with Ihc implementalion of appropriatc drainagc and crosion r,+casures, the abovc criteria will be satisficd. Our rccummcndations for drainagc and crosion conlrol arc pro��idcd bclow. Drainage Recommendations 13ccausc of thc dcpositional naturc of thc soils al Ihc sitc whcrc impermcablc soils (typically glacial till and hard silQ arc intcrlaycred with granular soils (prcdominatcly outwash sand), it is likcly that perchcd subsurfacc watcr or sccps may bc cncountcred during ca�7h��•ork activitics complctcd at thc sitc. \ �7 c o G n g i n c c r s 11078-001-00 � II ( I /