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24-8009 Page 6 The subject site is not included within any Earthquake Fault Zones as created by the Alquist- Priolo Earthquake Fault Zoning Act (CGS, 2018). Our review of geologic literature pertaining to the site area indicates that there are no known active or potentially active faults located within or immediately adjacent to the subject property. The nearest active fault is the Peralta Hills Fault which is approximately 5.1 miles northeast of the site. The next nearest faults are Bolsa Fairview Fault which is approximately 7.4 miles southwest of the site, the Yorktown Fault which is approximately 7.7 miles southwest of the site, the Adams Avenue Fault which is approximately 8.7 miles southwest of the site, and the North Branch Fault which is approximately 9.7 miles southwest of the site. The regional fault map, Figure 4, shows the location of the subject site in respect to the regional faults. Surface Fault Rupture and Ground Shaking Since no known faults are located within the site, surface fault rupture is not anticipated. However, due to the close proximity of known active and potentially active faults, severe ground shaking should be expected during the life of the proposed structures. Liquefaction Liquefaction is a seismic phenomenon in which loose, saturated, fine-grained granular soils behave similarly to a fluid when subjected to high-intensity ground shaking. Liquefaction occurs when these ground conditions exist: 1) Shallow groundwater; 2) Low density, fine, clean sandy soils; and 3) High-intensity ground motion. Effects of liquefaction can include sand boils, settlement, and bearing capacity failures below foundations. A review of the seismic hazard zone map of the Orange Quadrangle indicates that the subject site is not located within an area having a potential for earthquake induced liquefaction (Figure 5). Based on the above and the absence of shallow groundwater, the potential for liquefaction at the subject site is considered to be low. Seismically Induced Settlement Ground accelerations generated from a seismic event can produce settlements in sands or in granular earth materials both above and below the groundwater table. This phenomenon is often referred to as seismic settlement and is most common in relatively clean sands, although it can also occur in other soil materials. Based on the nature of the soils underlying the site the potential for seismically induced settlement is considered low. Lateral Spreading Seismically induced lateral spreading involves primarily movement of earth materials due to earth shaking. Lateral spreading is demonstrated by near-vertical cracks with predominantly horizontal movement of the soil mass involved. Based on the nature of the soils underlying the site and the generally flat lying topography the potential for lateral spreading at the subject site is considered very low. Earthquake Induced Landsliding Landsliding involves downhill motion of earth materials during or subsequent to earth shaking. Historically, landslides triggered by earthquakes have been a significant cause of damage. Areas that are most susceptible to earthquake induced landslides are areas with steep slopes in 2039 N Victoria Drive #24/28/2025