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1 <br /> 1 June 23, 2014 <br /> Project No. T-6241 <br /> ' Considering the site is underlain by glacially consolidated and overridden sediments, it is our opinion that the <br /> potential for earthquake damage at the site resulting from seismically induced differential settlement, and ground <br /> ' shaking is negligible. <br /> Liquefaction is a phenomenon where there is a reduction or complete loss of soil strength due to an increase in <br /> water pressure induced by vibrations. Liquefaction mainly affects geologically recent deposits of fine-grained <br /> sands that are below the groundwater table. Based on the soil and groundwater conditions we observed in our <br /> site explorations, it is our opinion that there is no risk for liquefaction to occur at this site during a severe seismic <br /> event. <br /> Based on soil conditions observed in the test borings, test pits, and our knowledge of the area geology, per <br /> ' Chapter 16 of the 2012 International Building Code (IBC), site class "C" should be used in structural design. <br /> Based on this site class, in accordance ,vith the 2012 IBC, the following parameters should be used in computing <br /> seismic forces: <br /> Seismic Design Parameters (IBC 2012 <br /> g ) <br /> ' Spectral response acceleration(Short Period), SR„ 1.455 <br /> Spectral response acceleration (1 —Second Period), S,,,, 0.728 <br /> Five percent damped .2 second period, S,,, 0.970 <br /> ' Five percent damped 1.0 second period, Si„ 0.485 <br /> Values determined using the United States Geological Survey (USGS) Ground Motion Parameter Calculator- <br /> ' accessed on A4ay 19, 2014 at the web site http://earthquake.usgs.gov/designnnaps/us/application.php. <br /> ' 5.0 DISCUSSION AND RECOMMENDATIONS <br /> 5.1 General <br /> Based on our study, there are no geotechnical conditions that would preclude the development of the site as <br /> ' currently planned. The industrial buildings can be supported on conventional spread footings bearing on <br /> competent native soils underlying the organic surficial soils, or on structural fill placed on a subgrade of <br /> competent native soils. Floor-slabs and pavements can be similarly supported. <br /> ' The native near-surface and deeper glacial till soils observed at the site contain a significant amount of fines and <br /> will be difficult to compact as structural fill when too wet or too dry. The ability to use these native soils from <br /> ' site excavations as structural fill will depend on its moisture content and the prevailing weather conditions at tine <br /> time of construction. If grading activities will take place during the wet winter months, the owner should be <br /> prepared to import clean granular material for use as structural fill and backfill. <br /> 1 <br /> Page No. 6 <br />