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City of Pleasanton—Villages at the Quarry Project 15183 Consistency Checklist Consistency Checklist 121 potential to contain vertebrate fossils, MM GEO-6 requires paleontological monitoring of all proposed excavations. As such, impacts related to destruction of a paleontological resource or unique geologic feature would be less than significant. Proposed Project Analysis and Conclusion Geologic mapping indicates that the project site is mapped within Holocene-age alluvial gravel, sand, and clay (Qa). While not mapped within the project site, Pleistocene-age alluvial gravel and sand (Qoa) and Pleistocene-age Livermore Gravel occur in proximity to the project site— south of Arroyo Valle.16 The Geotechnical Report confirms the presence of Holocene-age sediments underlying the project site; however, a subsurface investigation encountered existing fill across the project site, varying in thickness between approximately 17 and 50 feet.17 While Holocene- and Pleistocene-age sediments are known to contain significant paleontological resources, recent fill deposits are considered to have no potential. This is due to the relatively young age of fill deposits— which are too young to preserve fossils—and because fill deposits are disturbed and lack stratigraphic context. According to the Geotechnical Report, excavations associated with the construction of the proposed project are not expected to extend into previously undisturbed Holocene- or Pleistocene-age sediments.18 As such, the proposed project would not disturb sediments with a high potential to contain significant paleontological resources. Although the potential to impact significant paleontological resources is low, as discussed above, Housing Element Update FEIR MM GEO-6 would be implemented. Housing Element Update FEIR MM GEO-6 would require a site survey to confirm that no paleontological resources occur at the project site, and includes proper protocols to follow if significant paleontological resources are discovered at the project site. Housing Element Update FEIR 16 Dibblee, T.W., and J.A. Minch (Dibblee and Minch). Geologic Map of the Livermore Quadrangle, Contra Costa and Alameda Counties, California. Dibblee Foundation Map DF-196. Dibblee Geological Foundation. Map. Scale 1:24,000. 17 ENGEO Incorporated (ENGEO). 2024. Preliminary Geotechnical Report for Kiewit Property, Pleasanton, California. March 8, 2021, Latest Revision June 19, 2024. 18 Ibid.