PC-2026-15 - Laserfiche WebLink

ARROYO LAGO RESIDENTIAL PROJECT ADDENDUM FCS 155 Https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480036/Addendum/21480036 Arroyo Lago Residential Project Addendum.docx of pile driving or similar vibration causing construction methods, and therefore this requirement would not apply to the proposed project under its current application. The City does not establish numeric thresholds for other types of construction-related groundborne vibration impacts; therefore, for purposes of this analysis, the City, in its discretion, has elected to apply FTA construction vibration criteria, consistent with the Prior FEIR. A peak particle velocity (PPV) of 0.2 in/sec at the nearest structure is used as the threshold for potential building damage. The proposed project would involve substantially the same construction period, equipment, and processes as the County Project, with a reduced footprint and slightly reduced unit count. The nearest existing residential structures are approximately 25 feet west of the construction footprint where the heaviest vibration generating equipment could operate. At this distance, vibration from bulldozers would be approximately 0.089 in/sec PPV, well below the 0.2 in/sec threshold. Vibratory rollers, used for internal streets, would operate approximately 100 feet away, generating up to 0.013 in/sec PPV as measured at the nearest receiving structure, also well below the threshold. Given that equipment types and distances from construction footprints to receptors remain comparable, construction vibration would not exceed the applicable criteria, and the impact would remain less than significant consistent with the Prior FEIR’s impact conclusion. Operational Vibration Impacts Similar to the County Project, implementation of the proposed project would not include any permanent sources of vibration that would expose persons in the project vicinity to groundborne vibration levels that could be perceptible without instruments at any existing sensitive land use in the vicinity of the project site. Therefore, the proposed project would not generate groundborne vibration or groundborne noise levels in excess of established standards and, similar to the conclusions of the Prior FEIR, would result in a similar less than significant impact related to operational groundborne vibration. Given these considerations, the proposed project’s groundborne vibration impact from operations would be less than significant. Therefore, the project construction and operational groundborne vibration impact would continue to be less than significant consistent with the impact conclusions of the Prior FEIR, and the proposed project would not introduce new significant impacts or create substantially more severe significant impacts than those previously identified in the Prior FEIR. No additional analysis is required.