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Environmental Impacts of the Proposed Changes to the Original Project Addendum to the City of Pleasanton Downtown Specific Plan Final Environmental Impact Report 33 impacts to cultural resources related to the resource. Pursuant to the data recovery plan, the qualified archaeologist and Native American representative, as appropriate, shall recover and document the scientifically consequential information that justifies the resource’s significance. The City shall review and approve the treatment plan and archaeological testing as appropriate, and the resulting documentation shall be submitted to the regional repository of the California Historical Resources Information System, per CCR Guidelines Section 15126.4(b)(3)(C). Paleontological Resources Ground-disturbing construction activities in previously undisturbed sediments with high paleontological sensitivity could result in significant impacts to paleontological resources. Significant impacts to paleontological resources include the destruction, damage, or loss of scientifically important paleontological resources or associated stratigraphic data. The Barone’s project site is mapped as Quaternary (Holocene) floodplain deposits by Helley and Graymer (1997). Holocene floodplain deposits consist of gray sandy or silty clay with occasional lenses of silt, sand, or gravel. Test borings conducted for the project’s geotechnical investigation encountered a 7-inch layer of asphalt and artificial fill, clay, and sandy silt from 7 inches to 12 feet, and clayey to gravelly sand from 12 to 48 feet (Geo-Logic Associates 2020). The description of the sediments from 7 inches to 12 feet, which are anticipated to be the only sediments impacted by Barone’s project construction, generally agrees with the description of Quaternary (Holocene) floodplain deposits of Helley and Graymer (1997). Holocene-aged sediments are generally considered too young (i.e., less than 5,000 years old) to preserve paleontological resources, as described in the Society of Vertebrates Paleontology (SVP; 2010) guidelines. Therefore, Quaternary (Holocene) floodplain deposits have low paleontological sensitivity. Holocene-aged geologic units, such as Quaternary (Holocene) floodplain deposits, may be underlain by older (i.e., 5,000 years old or more), higher-sensitivity sediments in the subsurface. The depth at which this transition to 5,000-year-old sediments occurs is unknown. Ground-disturbing construction activities for the Barone’s project will include grading for building pads and excavations for new utilities, sewer lines, and storm water infrastructure, that is expected to require up to 4,200 CY of excavated sediment. Grading for building pads is expected to reach as much as 5 feet below the surface. At this depth, it is unlikely that 5,000-year-old sediments will occur. Excavations for utility lines and stormwater infrastructure will reach as much as 9 feet below the surface. Although it is more likely that older, potentially paleontologically sensitive sediments will be encountered at this greater depth, the overall volume of such sediments would be small. Therefore, the potential impacts to paleontological resources as a result of the Barone’s project are the same as those identified in the Final EIR. Human Remains As discussed in the Final EIR, human remains could be disturbed during project grading and excavation activities. The discovery of human remains is regulated by Public Resources Code Section 5097.98 and California Health and Safety Code Section 7050.5 and 7052. In the event of an unanticipated discovery of human remains, the County Coroner must be notified immediately. If the human remains are determined to be prehistoric, the coroner will notify the Native American Heritage Commission, which will determine and notify a most likely descendant (MLD). The MLD must complete the inspection of the site within 48 hours of being granted access and provide recommendations as to the treatment of the remains to the landowner. With adherence to existing regulations, impacts to human remains would be less than significant.