6605 HARDESON RD BASE FILE 2016-01-01 MF Import

Intracorp 'September 21, 1998 t� �: '� •� ': '� E-3592-7Z0 Paps 6 The Puget Lowland is classified as � Seismic Zone 3 in the 1997 Uniform Building Gode (UBCI. Earthquakes occur in the Puget Lowland with regularity, however, the majority of these events are of such low magnitude they are not detected without instruments. Lerge earthquakes do occur, as indicated by the 1949, 7.1 magnitude earthquake in the Olympia area and the 1965, 6.5 magnitude earthquake in the Midway area. There are four potential geologic hazards associated with a st�ong motion seismic event at thia site: ground rupture, slope failure, tiquefaction, and ground motfon response. �ro�nd Runture: The strongest earthquakes in the Puget Lowland are widespread, subcrustal events, ranging in depth from thirCy (30) to fifty-five (55) miles. Surface faulting from these deep events has not been documented to date. Therefore, it is our opinion, that the risk of ground rupture during a strong motion seismic event is negligibie. Slooe Faiiure: The medium dense to dense soils encountered in the test pit excavations should not be adversely affected by a strong motion event. Liauefaction: Liquefaction is a phenomenon in which soils lose ail shear strength for short periods of time during an earthquake. Groundshaking of sufficient duration results in the loss of grain to grain contact and rapid increase in pore water pressure, causing the soil to behave as a fluid. To have a potential for liquefaction, a soil must be cohasioniess with a grain size distribution of a specified range (generally sands and silt); it must be loose to medium dense; it must be below the groundwater table; and it must be subject to sufficient magnitude and duration of groundshaking. The effects of liquefaction may be large total and/or differential settlement for structures founded in the liquefying soils. In our opinion, the potentiai for liquefaction induced settlement at the site is low. �ro�nd Motion Resoonse: The 1997 UBC Earthquake regulations contain a static force procedure and a dynamic force procedure for design base shear calculations. Based on the encountered soil conditions, it is our opinion soil profile type So, Stiff Soil as defined in Table 16-J shouid be used to characterize the site soils. Excavations and looes The following information is provided solely as a service to our client. Under no circumstances should this information be interpreted to mean that ECI is assuming responsibility for construction site safety or the contractor's activities; such responsibility is not being irr�piied and should not be inferred. ErN Carukr�b. Mc.