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69 seismic events, in addition to the potential for liquefaction or landslides. The Focused GPU EIR concluded that with implementation of Public Safety Element and compliance with the regulatory framework, impacts related to unstable soils would be reduced to less than significant. No changes to geologic substructures are expected to occur as a result of Housing Component implementation. As described in item (a) above, the proposed Housing Component would comply with all applicable local and State codes and regulations, and Housing Component design would incorporate City-approved geotechnical recommendations for site development. This impact is considered less than significant. All grading plans are subject to City review and approval. Also see item (a) above for a summary of the geotechnical report findings regarding proposed foundation types and techniques recommended to counter the high expansion potential of onsite surface soils. As the proposed Housing Component would have a less-than-significant impact with the incorporation of standard conditions and compliance with the regulatory framework, it would be consistent with the Focused GPU EIR. It would not create new impacts or increase impacts and there is no new information of substantial importance for CEQA purposes. d. The Focused GPU EIR determined portions of the Planning Area contain soils that have a high clay content, creating expansion potential (p. 4.7-16). This type of soil constraint could impact future structures and their occupants within the Planning Area. The Focused GPU EIR concluded existing General Plan policies and programs intended to protect against geologic and seismic hazards, including Policies PS-6.1 and PS-6.1 and Programs PS-23 and PS-24, in conjunction with conformance with the California State Building Code (which shall be required as conditions of approval for the project component) would reduce the project component’s potential effects related to soil constraints, including expansive soils, to a less-than-significant level. According to the Housing Component-specific geotechnical report (p. 9), laboratory testing results show the surface soils of the project component site consist of clay with high plasticity underlain by loose to dense clayey and silty sands (p. 3). The site’s soils have a high expansion potential when subjected to fluctuations in moisture levels. The geotechnical report recommends that the building foundation should consist of a relatively thick mat with stiffening grade beams or, alternatively, a series of rigid continuous spread footings constructed in a grid pattern (pp. 9-10). Due to the potential for liquefaction and the expansion potential of the site’s soils, a structural slab floor at the ground level would be preferable to conventional slab-on-grade floors from a geotechnical viewpoint. In addition, a layer of non- expansive fill should be placed below slab floors. All recommended solutions would be subject to City review and approval for feasibility and effectiveness. As discussed, the GPU EIR determined impacts from expansive soils to be less than significant with mitigation. As the Housing Component would have a less-than-significant impact with the incorporation of standard conditions of approval and compliance with the regulatory framework, it would be consistent with the Focused GPU EIR. It would not create new impacts or increase impacts, and there is no new information of substantial importance for CEQA purposes. e. The Focused GPU EIR did not address impacts related to adequate soils for the use of septic tanks or alternative wastewater disposal systems because septic systems are not appropriate within urbanized areas. The Focused GPU EIR concurred and found the impact to be less than significant. There would be no use of septic tanks or alternative wastewater disposal systems for the Housing Component. No impact would occur. Because the Housing Component would connect to the existing sewer system, this component is consistent with the analysis in the GPU EIR. It would not create new impacts or increase impacts and there is no new information of substantial importance for CEQA. f. The Focused GPU EIR stated that the Planning Area is not known to have paleontological resources but could potentially contain previously undiscovered resources (p. 4.7-18). Regarding unique geological resources, the Focused GPU EIR notes proposed development on previously undisturbed land that contains steep slopes, rocky outcroppings, or unique geological features. These areas are more likely to contain isolated unique geologic features. Proposed development in the Planning Area has the potential to destroy unique paleontological resources (p. 4.7-18). The Focused GPU EIR discusses the existing measures and regulations that reduce potentially significant paleontological resources impacts in the Planning Area. These include Redwood City’s Cultural Resources Management Plan, which requires development proponents to consult with the Northwest Information Center (NWIC), a standard City condition of approval requiring work stoppage in the even ground disturbing activities identify paleontological resources, and the City’s standard procedures requiring a qualified paleontologist’s assessment of the potential for development proposed to destroy paleontological resources prior to the issuance of grading and demolition permits (p. 4.7-18). The Focused GPU EIR concluded the City’s established processes under ATTY/RESO.0031/CC RESO CEQA GUIDELINES (901 EL CAMINO REAL) REV: 04-22-25 VR Page 69 of 148