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Page 6 of 7 and sight distances available. There is no reason to conclude that the project residents use of on-street parking spaces would create a hazardous condition or worsen public safety. Neighboring private parking lots (such as that at St. Clare’s church) have the right and the ability to enforce restrictions through signage, barriers or towing of illegally parked vehicles. Buildings Potential for Sinking/Subsidence A Geotechnical Investigation was prepared for the proposed project by Cornerstone Earth Group (CEG) dated August 30, 2023. As part of the Geotechnical Investigation, CEG conducted four exploratory soil borings to depths ranging from six to 30 feet below ground surface to evaluate current soil conditions. Although the site is underlain by soils that can become plastic (i.e. soils that shrink and swell under seasonal wetting and drying cycles), several specific recommendations have been offered to address this issue. For example, CEG has recommended post-tensioned concrete mat foundation systems for all of the buildings. Post-tensioning is a structural technique that applies continuous pressure from tensioned steel cables to cured concrete in order to prevent cracking. The mat foundations then act as rigid platforms onto which the buildings are constructed. Eliminating moisture fluctuations in the soil is another recommendation offered by CEG. If the moisture in the soil is held constant, then the shrink/swell cycle is interrupted. This will be accomplished using specific soil compaction and consolidation techniques during site grading. The moisture content will be carefully monitored and maintained until covered with impervious surfaces such as building foundations or pavements. For areas of the site subject to landscape irrigation, CEG has recommended deepened vertical curbs or foundation edges to isolate site improvements from planting areas. This ensures that irrigation water will not migrate beneath hard surfaces where constant soil moisture must be maintained. In addition, graded slopes will assure that rainwater is directed to a network of underground pipes and facilities that drain to the City’s pipe network. Landscaped areas where rain will intentionally pond for stormwater pollution prevention have been designed with buried membranes to assure moisture is not introduced into the soil. Liquefaction is another a phenomenon that can influence the ability of soil to support heavy loads such as building foundations. Liquefaction occurs when granular soils like sand become disturbed during an earthquake. The cyclic nature of an earthquake can cause sand to momentarily lose its cohesive properties thus causing rapid settlement. Fortunately, the site is not underlain by granular soils that could be subject to liquefaction. CEG only encountered stiff cohesive materials in their soil borings and thus concluded that liquefaction is not a concern. The California Building Standards Commission (CBSC)2, as adopted by the City in Section 20.08.010 of the Pleasanton Municipal Code, provides standards to protect property and public safety by regulating the design and construction of excavations, foundations, building frames, retaining walls, and other building elements, which would further reduce the potential for seismic-related ground failure, including liquefaction. Compliance with the aforementioned uniformly applicable development regulations would ensure that the potential for risks related to liquefaction would be less than significant. 2 The CBSC provides minimum standards to ensure that proposed structures would be designed using sound engineering practices and appropriate engineering standards for the seismic area in which the project site is located.