1808 MERRILL CREEK PKY 2016-01-01 MF Import

. ,. ,,�` . Omniplan E-3592-610 � •' July.9, 1996 Page 7 �eismtc Design Conalderali,ona 7he Puget Lowland is classified as a Seismic Zone 3 in the 1994 Uniform Bullding Cocle {U8C). Earthquakes occur in the Puget Lowland with regularity, however, the majority of thesa events are of such low magnitude they are not telt wlthout inst�uments. Large earthquflkes do occur, as indicated by the 1949, 7.2 m��nituJe aarthquake in tho Olympia area and the 1965, 6.5 magnitude earthquakc in the Midway area, 7here are three poten;ial geologic hazards associated with a strong motion selsmic ev�nt at this site: ground rupture, liquefaction, and c�round motlon response. Ground Rupture The stron�r,st earthquakes In the Puget Lowland are widespread, subcrustal events, ranging in depth from thirty (30) to fiFty-Five (5G) milos, Surface faulting from those deep events has not been documented to date, Therefore, it is our opinion that the risk of ground rupturo at this slte during a scrong motion seisrnic event is negllgible. ' Llquetaction • liquefaction is a phenornenon In which soils lose all shear stren�th for short periods of ` i ' tlme during an earthquake. Groundshaking of sufficient duration results in the loss of ' ,,,� graln to grain contact and rapid incroase in pore water pressuro, causing the soil to behave �.e as a (luld. To have a potendal for liquefaction, a soil must bu cohesioniess with a grain j.��t �. , . sixe distribution of a specified range (generally sand and silt); it must be loose; it must be ;: �:} below the groundwater taBle; and it must bo subJect to sufficiont magnitude and duration ' of proundshaking. The effects of Ilquefaction may be large total and/or differential settlement for structures founded in the Ifquefying soils. in our opinion, th� potentlai for liquefaction (nduced settlernent for the fill being used to achieve conscructlon subgrade olevatlons should be negligible. �-, � � �� �. � �� � : ��. ; Emib CnnnW�enu. Ina.