Reso PC22-06 0079 PC Reso Recommending Certification of the SEIR

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4. Mitigation Monitoring and Reporting Program TABLE 4-1 (CONTINUED) TRANSIT DISTRICT DTPP AMENDMENTS MITIGATION MONITORING AND REPORTING PROGRAM Redwood City Transit District DTPP Amendments 4-13 ESA / 202100421.00 Final EIR October 2022 MITIGATION MEASURES Monitoring Program Implementation Responsibility Monitoring and Reporting Action Monitoring Responsibility Monitoring Schedule Geology and Soils (cont’d.) Mitigation Measure GEO-2 (cont’d.) Erosion during all phases of construction shall be controlled through the use of erosion and soil transport control facilities. These shall include the use of catch basins and filter fabrics, and the direction of stormwater runoff away from disturbed areas. The plans shall also provide for long-term stabilization and maintenance of remaining exposed soils after construction is completed. Areas disturbed by construction shall be either covered with impervious surfaces (e.g., buildings and pavement) or fully stabilized with landscaping and/or native vegetation. All revegetated areas shall be irrigated and maintained as necessary to ensure the long-term survival of the vegetation. Mitigation Measure GEO-4a (formerly Mitigation Measure 16-1 from the DTPP Final EIR with clarifying amendments): The detailed, design-level geotechnical investigations required by the City Building Official shall include analysis of expansive soil hazards and recommend stabilization measures. Once grading plans have been developed, the actual use of expansive soils in engineered fill construction shall be further evaluated by a geotechnical engineer and the location primary borrow source areas for fills shall be determined. Additionally, supplemental field and laboratory testing of potential cut materials shall be completed. In addition to observing all cut and fill slope construction, the project geotechnical engineer shall inspect and certify that any expansive soils underlying individual building pads and all roadway subgrades have been either removed or amended in accordance with City-approved construction specifications. If expansive soils are not fully remediated on each lot and in the area of all public and private improvements at the time of site development, the project geotechnical engineer shall make site-specific recommendations for grading, drainage installation, foundation design, the addition of soil amendments, and/or the use of imported, non-expansive fill materials, as may be required to fully mitigate the effects of weak or expansive soils and prevent future damage to project improvements. These recommendations shall be reviewed by a City-retained registered geologist and, following his or her approval, be incorporated into a report to be included with each building permit application and with the plans for all public and common area improvements. In addition, since proper drainage, in particular, can improve the performance of expansive soils by significantly reducing their tendency to shrink and swell, deed restrictions shall be imposed to prohibit significant modification of finished lot grades that would adversely affect site drainage. Project Applicant, project geotechnical engineer, City Building Official 1. Prepare detailed design-level geotechnical investigation and incorporate measure into construction specifications 2. Conduct supplemental field and laboratory testing, and inspection 3. Prepare site- specific recommendations if expansive soils not fully remediated on each lot and incorporate into a report to be included with each building permit application 1. City 2. City 3. City 1. Prior to issuance of grading permit 2. During construction 3. Prior to issuance of building permits for future projects