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File: 218267 November 30, 2018 Ground Shaking - The subject site is likely to be subject to very strong to violent ground shaking during its life span due to a major earthquake in one of the above-listed fault zones. Current (2016) building code design may be followed by the structural engineer to minimize damages due to seismic shaking, using the following input parameters from the USGS Java Ground Motion Parameter Calculator based upon ASCE 7-10 design parameters: Site Class -D I SMs = 1.512 1 SM, = 1.029 1 SDs= 1.008 SDi =0.686 Landsliding-We note that the subject site and the surrounding area are generally level. The Seismic Hazards Zone Map indicates that the site is not in an area potentially subject to seismically induced landsliding. Therefore,the hazard due to seismically-induced landsliding is, in our opinion, very low for the site. Liquefaction - Liquefaction most commonly occurs during earthquake shaking in loose fine sands and silty sands associated with a high ground water table. These conditions were demonstrated to be absent in the upper 19.5 feet of site materials, which is consistent with the State's mapping which indicates that the site is not within an area potentially subject to liquefaction. Therefore, it is also our opinion the liquefaction is unlikely to occur on the subject property. Ground Subsidence - Ground subsidence may occur when poorly consolidated soils densify as a result of earthquake shaking. Since the proposed building site is underlain at shallow depths by resistant materials, the hazard due to ground subsidence is, in our opinion, considered to be low. Lateral Spreading- Lateral spreading may occur when a weak layer of material, such as a sensitive or liquefiable soil, loses its shear strength as a result of earthquake shaking. Overlying blocks of competent material may be translated laterally towards a free face. Free face conditions are not present proximate to or at the site, hence, the hazard due to lateral spreading is, in our opinion, considered to be low. Site Preparation and Grading All debris resulting from the demolition of existing improvements should be removed from the site and may not be used as fill. Any existing underground utility lines to be abandoned should be removed from within the proposed building envelope and their ends capped outside of the building envelope. Any vegetation and organically contaminated soils should be cleared from the building area. All holes resulting from removal of tree stumps and roots, or other buried objects, should be overexcavated into firm materials and then backfilled and compacted with native materials. 6