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a-ii)Less-than-Significant Impact. As previously discussed, the Project site is not located within an Alquist—Priolo
<br /> Earthquake Fault Zone. However, similar to other areas located in seismically active Northern California, the Project
<br /> area is susceptible to strong ground shaking during an earthquake, although the site would not be affected by ground
<br /> shaking more than any other area in the region would be.
<br /> The Project would be required to comply with the most recent version of the California Building Code (CBC), which
<br /> contains universal standards related to seismic load requirements, and is codified within the San Joaquin County
<br /> Ordinance Code under Section 8-1000. In addition, pursuant to Section 9-905.11, project implementation will require
<br /> preparation of a site-specific geotechnical investigation report by a state-registered geotechnical engineer. The site-
<br /> specific geotechnical investigation report includes an evaluation of on-site soils and their related potential to result in
<br /> seismic hazards, and if necessary, prescribes corrective measures to ensure structural stability in the event of seismic
<br /> activity. Pursuant to the Section 9-905, the recommended actions of a geotechnical investigation must be
<br /> incorporated into site preparation and construction.
<br /> A site-specific geotechnical investigation has been prepared by Cornerstone Earth Group in February 2020 for the
<br /> project and includes recommendations to ensure structural stability, including compaction requirements, removal of
<br /> existing fills and replacement with engineered fill, and foundation construction requirements (CEG 2020). Compliance
<br /> with the CBC and the engineering recommendations in the site-specific geotechnical investigation report, which will be
<br /> reviewed and verified by County staff, would ensure structural integrity in the event that seismic ground shaking is
<br /> experienced at the Project site. Therefore, impacts associated with seismic ground shaking would be less than
<br /> significant, and this issue will not be evaluated further in the Draft EIR.
<br /> a-iii) Less-than-Significant Impact. Soil liquefaction is a seismically induced form of ground failure. Liquefaction is a
<br /> process by which water-saturated granular soils transform from a solid to a liquid state because of a sudden shock or
<br /> strain such as an earthquake.
<br /> The project site's subsurface is composed of several interbedded layers of medium-density sands and stiff to hard
<br /> clays and silts to approximately 50 feet below ground surface. Below a depth of 50 feet, the subsurface is primarily
<br /> composed of stiff to hard clays and silts. Soil samples taken from the project site as part of the site-specific
<br /> geotechnical investigation report indicate that on-site soils could potentially experience liquefaction resulting in
<br /> settlement on the order of 0.25 inches or less. As a result, the geotechnical investigation (CEG 2020) includes
<br /> engineering specifications to mitigate potential impacts related to liquefaction. Compliance with the CBC and the
<br /> engineering recommendations in the site-specific geotechnical investigation report, which will be reviewed and verified
<br /> by County staff, would ensure structural integrity in the event that liquefaction is experienced at the Project site.
<br /> Therefore, impacts associated with liquefaction would be less than significant, and this issue will not be further
<br /> evaluated in the Draft EIR.
<br /> a-iv) No Impact. The project site is located in an area that is relatively flat and does not contain any slopes that could
<br /> result in landslides. Although the project site currently contains various depressions and elevations, the topography of
<br /> the project site will be brought to a flat grade as part of grading activities. Upon completion of grading activities, the
<br /> project site will be flat, similar to the surrounding area. As such, there is no potential for landslides to occur on or near
<br /> the project site. Therefore, impacts associated with landslides would be less than significant, and this issue will not be
<br /> further evaluated in the Draft EIR.
<br /> b) Less-than-Significant Impact. The Project would involve earthwork and other construction activities that would
<br /> disturb surface soils and temporarily leave exposed soil on the ground's surface. Common causes of soil erosion from
<br /> construction sites include stormwater, wind, and soil being tracked off site by vehicles. To help prevent erosion,
<br /> Project construction activities must comply with all applicable federal, state, and local regulations for erosion control.
<br /> The Project would be required to comply with standard regulations, including the provisions of the National Pollutant
<br /> Discharge Elimination System (NPDES) Construction General Permit. Construction activities subject to this permit
<br /> include clearing, grading, and ground disturbances such as stockpiling and excavating. The NPDES Construction
<br /> General Permit requires implementation of a stormwater pollution prevention plan (SWPPP), which would include
<br /> construction features for the project (i.e., best management practices [BMPs]) designed to prevent erosion and protect
<br /> the quality of stormwater runoff. Sediment-control BMPs may include stabilized construction entrances, straw wattles
<br /> on earthen embankments, sediment filters on existing inlets, or the equivalent. Therefore, construction impacts
<br /> associated with soil erosion would be less than significant, and this issue will not be further evaluated in the Draft EIR.
<br /> Once redeveloped, the Project site would include buildings, paved surfaces, and other on-site improvements that
<br /> would stabilize and help retain on-site soils. The remaining portions of the Project site containing pervious surfaces
<br /> would primarily consist of landscape areas. These landscape areas would include a mix of trees, shrubs, plants, and
<br /> groundcover that would help retain on-site soils while preventing wind and water erosion from occurring. Therefore,
<br /> operational impacts related to soil erosion would be less than significant, and this issue will not be further evaluated in
<br /> the Draft EIR.
<br /> Enter oroiect#s. —Initial Study 16
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