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625 Cypress Avenue Geotechnical Investigation Project No. W1895-88-01 - 7 - April 23, 2024 6.3.2 Deterministic Seismic Hazard Analysis In order to define the deterministic scenario events, deaggregation of the uniform hazard probabilistic response spectrum was performed using the USGS Uniform Hazard Tool. The inversion approach used by UCERF-3 allows for a large number of variations for each source scenario, including multi-fault ruptures. Therefore, deaggregation of UCERF-3 consists of the contributions from multi-fault ruptures rather than individual source contributions. To address this, the USGS Unified Hazard Tool aggregates the contributions on a per-fault-section basis, with rupture contributions only ever counted once. The Unified Hazard Tool deaggregation contributor list shows the fault sections which contribute most to hazard at a site and reports a mean earthquake magnitude for each section identified by a 'parent' fault name and section index. Based on the deaggregation, we have considered scenario events with the greatest contribution to the deterministic ground motions. The magnitudes of the deterministic scenario events were based on the BSSC 2014 Scenario Event Catalog which includes the parent fault identified in the deaggregation and which has the largest earthquake magnitude. Other fault source parameters were defined by the values in the BSSC2014 Scenario Catalog. The values of Z2.5 and Z1.0 were estimated using data from the Community Velocity Model (CVM) Version 4 developed by Southern California Earthquake Data Center (SCEDC) accessed by the OpenSHA Site Data Application (v1.5.2). The input values used to evaluate the deterministic scenario(s) are provided on Figure 12. The deterministic median and standard deviation (sigma) for the scenario events were evaluated using the USGS NSHMP-HAZ-WS Response Spectra online application. The deterministic analysis used the same four GMPEs, equally weighted, to generate the median and standard deviation of the ground motion which were then used to calculate the 84th percentile at 5% damping. The median spectral accelerations were rotated to maximum direction using the period specific ratios from Shahi et al. (2013 & 2014). The deterministic scenarios were compared, and the event occurring on the San Joaquin Hills fault is considered the controlling deterministic event. The 84th percentile maximum rotated component deterministic response spectrum is provided on Figure 7. 6.3.3 Site-Specific Response Spectrum The lesser of the probabilistic and deterministic MCER response spectra is the Site-Specific MCER. Two thirds of the Site-Specific MCER is the Design Earthquake (DE) Response Spectrum, provided the results