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Phelan Development Holly Master Plan - Buildings H & 1 15188.000.006 Geotechnical Exploration 3.7 2019 CBC SEISMIC DESIGN PARAMETERS The 2019 CBC utilizes design criteria set forth in the 2016 ASCE-7 Standard. Based on the subsurface conditions encountered and utilizing an average shear wave velocity of approximately 875 feet per second as determined from measurements obtained during subsurface investigation, we characterized the site as Site Class D (stiff soil) in accordance with the 2019 CBC. We provide the 2019 CBC seismic design parameters in Table 3.7-1 below, which include design spectral response acceleration parameters based on the mapped Risk-Targeted Maximum Considered Earthquake (MCER) spectral response acceleration parameters. TABLE 3.7-1: 2019 CBC Seismic Design Parameters, Latitude: 37.76981 Longitude: -121.42063 PARAMETER VALUE Site Class D Mapped MCER Spectral Response Acceleration at Short Periods, Ss (g) 1.066 Mapped MCER Spectral Response Acceleration at 1-second Period, S1 (g) 0.378 Site Coefficient, FA 1.074 Site Coefficient, Fv Null* MCER Spectral Response Acceleration at Short Periods, SMs (g) 1.144 MCER Spectral Response Acceleration at 1-second Period, SM1 (g) Null* Design Spectral Response Acceleration at Short Periods, SDs (g) 0.763 Design Spectral Response Acceleration at 1-second Period, SD1 (g) Null* Mapped MCE Geometric Mean (MCEG) Peak Ground Acceleration, PGA(g) 0.443 Site Coefficient, FPGA 1.157 MCEG Peak Ground Acceleration adjusted for Site Class effects, PGAM (g) 0.513 Long period transition-period, TL 8 sec *Requires site-specific ground motion hazard analysis per ASCE 7-16 Section 11.4.8 We recommend that we collaborate with the structural engineer of record to further evaluate the effects of taking the exceptions on the structural design and identify the need for performing a site-specific seismic hazard analysis. We can provide a scope for site-specific seismic hazard analysis and ground motion study under separate cover, if needed. 4.0 CONSTRUCTION MONITORING Our experience and that of our profession clearly indicate that the risk of costly design, construction, and maintenance problems can be significantly lowered by retaining the design geotechnical engineering firm to: 1. Review the final grading and foundation plans and specifications prior to construction to evaluate whether our recommendations have been implemented, and to provide additional or modified recommendations, as needed. This also allows us to check if any changes have occurred in the nature, design, or location of the proposed improvements and provides the opportunity to prepare a written response with updated recommendations. 2. Perform construction monitoring to check the validity of the assumptions we made to prepare this report. Earthwork operations should be performed under the observation of our representative to check that the site is properly prepared, the selected fill materials are ENGEOPage 1 12 December 13, 2021 Expect Exceltence