Reso 2011-192 - Laserfiche WebLink

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FLN2009-00006; 2450 Washington Avenue October 2011 Mitigated Negative Declaration shaking and liquefaction. Geotechnical and seismic design criteria must conform to engineering recommendations in accordance with the seismic requirements of the 2010 California Building Code (Title 24) and any amendments adopted in the San Leandro Municipal Code. Additionally, because the project site is in a liquefaction Seismic Lazard Zone, the project applicant will be required to comply with the guidelines set forth by California Geological Survey Special Publication 117. Mitigation Measure #12: Applicant shall comply with the NPDES requirements that must incorporate permanent post- construction Best Management Practice (BMP) of the California Regional Water Quality Control Board and the City of San Leandro Building and Engineering Departments. The BMP shall be reviewed and approved by the City's Engineering Department prior to the issuance of a Grading Permit. Mitigation Measure #13: Applicant shall be required to completely remove all existing surface and subsurface structures prior to grading. If any of the following are encountered: concrete, septic tanks, gas and oil tanks, storm inlets, machinery, equipment, debris and trash, these should also be removed, with the exception of items specified by the owner for salvage. Ornamental trees to be removed should be properly grubbed to adequately remove all major root systems. In addition, all underground structures must be located on the grading plans so that proper removal may be carried out. Mitigation Measure #14: A qualified geotechnical consultant shall be required to observe the removal of subsurface structures and be notified in ample time to ensure that no subsurface structures are covered and that the root systems from grubbing operations are completely removed. If a qualified geotechnical consultant is not contracted to observe demolition and removal of existing structures, backhoe investigation in the areas of demolition shall be performed prior to commencement of mass grading. Mitigation Measure #15: The applicant shall be required to excavate, remove and recompact potentially liquefiable soil. In -site ground densification, for example, compaction with vibratory probes, dynamic consolidation, compaction piles, compaction grouting, etc., shall be conducted. Ground modification techniques, such as permeation grouting, columnar jet grouting; deep soil mixing, stone columns, gravel or other drains shall be implemented, and deep foundations shall be put in place to mitigate potential liquefaction- induced settlement impacts. Mitigation Measure #16: Following any required stripping and removal of any loose and/or soft soil and undocumented fills, the top eight inches of exposed native ground for fill areas shall be scarified, moisture conditioned as necessary, and compacted to a minimum relative compaction of 90% at a moisture content of at least 2 percent above optimum, as determined by ASTM D1557 -07 Laboratory Test Procedure. Mitigation Measure #17: All recommendations set forth in the May 11, 2009 Geotechnical Investigation shall be followed to ensure proper site preparation and grading of the project site is implemented, including adherence to Best Management Practices (BMPs). 5