GEOTECHNICAL INVESTIGATION REPORT Project Zeus Mare Island, Vallejo, California Prepared by: Amec Foster Wheeler Environment & Infrastructure, Inc. May 1, 2017 Project No. 6166150082 Copyright © 2015 by Amec Foster Wheeler Environment & Infrastructure, Inc. All rights reserved. May 1, 2017 Project Zeus Confidential Client Subject: Geotechnical Investigation Report Project Zeus Mare Island Site Vallejo, California Project No. 6166150082.14 Dear Project Zeus Client Team: Amec Foster Wheeler Environment & Infrastructure, Inc. (Amec Foster Wheeler) is pleased to present this Geotechnical Investigation Report for the Project Zeus Mare Island site, located in Vallejo, California. We appreciate the opportunity to work with you on this project. If you have any questions or require additional information, please feel free to contact Chris Coutu at [email protected] or (510) 663-4156, or any of the undersigned team members. Sincerely, Amec Foster Wheeler Environment & Infrastructure, Inc. Chris Coutu, PE, GE Donald Wells, PG, CEG Principal Engineer Senior Associate Engineering Geologist Direct Tel.: (510) 663-4156 Direct Tel.: (510) 663-4178 E-mail: [email protected] E-mail: [email protected] cc/dw/aw/ldu X:\6166150082\3000 Rpt\Zeus Rpt\1 txt, cvrs\Zeus_MareIsland_Geotech_Text_050117.docx TABLE OF CONTENTS Page 1.0 Introduction .................................................................................................................. 1 1.1 Purpose ........................................................................................................... 1 1.2 Project Description ........................................................................................... 1 1.3 Scope of Work ................................................................................................. 2 1.4 Project Team ................................................................................................... 3 1.5 Organization of Report ..................................................................................... 3 2.0 Regional and Local Site Setting .................................................................................. 4 2.1 Regional Geologic and Tectonic Setting .......................................................... 4 2.2 Seismic Setting ................................................................................................ 5 2.3 Local Site Setting ............................................................................................. 7 3.0 Data Review and Site Reconnaissance ...................................................................... 8 3.1 Data Reviewed ................................................................................................ 8 3.2 Site Reconnaissance and Surface Conditions ................................................. 9 4.0 Exploration and Testing Program .............................................................................. 10 4.1 Geotechnical Field Exploration ...................................................................... 10 4.2 Laboratory Test Results ................................................................................. 11 4.3 Vane Shear Test Results ............................................................................... 12 4.4 Geophysical Test Results .............................................................................. 12 5.0 SUBSURFACE CONDITIONS .................................................................................. 14 5.1 Geologic Materials ......................................................................................... 14 5.1.1 Fill ...................................................................................................... 14 5.1.2 Young Bay Mud ................................................................................. 15 5.1.3 Old Bay Clay ...................................................................................... 15 5.1.4 Older Alluvium ................................................................................... 16 5.1.5 Bedrock .............................................................................................. 16 5.2 Site Conditions ............................................................................................... 16 5.3 Groundwater Conditions ................................................................................ 17 6.0 GEOLOGIC and SEISMIC HAZARDS EVALUATION ............................................... 18 6.1 Seismic Hazard Analysis ............................................................................... 18 6.1.1 Approach for Probabilistic Ground Motion Analysis ........................... 18 6.1.2 Results of the Deterministic Seismic Hazard Analysis ....................... 20 6.1.3 Results of the Probabilistic Seismic Hazard Analysis ........................ 21 6.1.4 Development of General Procedure Response Spectrum ................. 21 6.1.5 Development of Site-Specific Horizontal Response Spectra ............. 22 6.2 Site Specific Ground Motions and Site Response ......................................... 23 6.2.1 Site-Specific Site Response Analysis ................................................ 23 6.2.2 Site Specific Design Peak Ground Acceleration ................................ 25 6.3 Geologic Hazards .......................................................................................... 26 6.3.1 Slope Instability and Landsliding ....................................................... 26 6.3.2 Flooding and Sea Level Rise ............................................................. 27 6.3.3 Settlement and Consolidation ............................................................ 27 6.3.4 Shrink Swell Potential ........................................................................ 28 6.3.5 Corrosion of Buried Concrete and Metals .......................................... 28 6.4 Seismic Geologic Hazards ............................................................................. 28 6.4.1 Surface Fault Rupture ........................................................................ 29 6.4.2 Liquefaction and Lateral Spreading ................................................... 30 6.4.3 Seismically Induced Compression and Settlement ............................ 31 Mare Island, California April 24, 2017 Page i 6.4.4 Seismically Induced Transient and Permanent Displacements ......... 32 6.4.5 Seismically Induced Landsliding ........................................................ 32 6.4.6 Seismically Induced Inundation ......................................................... 33 7.0 Geotechnical RECOMMENDATIONS ....................................................................... 34 7.1 Settlement From Liquefaction ........................................................................ 34 7.2 Settlement From Compressible Young Bay Mud ........................................... 35 7.2.1 Loads ................................................................................................. 36 7.2.2 Consolidation Parameters ................................................................. 36 7.2.3 Consolidation Settlement Analysis .................................................... 37 7.2.3.1 Anticipated Settlement without Mitigation ............................. 37 7.2.4 Mitigation for Settlement .................................................................... 38 7.2.4.1 Preloading ............................................................................. 39 7.2.4.2 Lightweight Fill ...................................................................... 41 7.2.4.3 Soil-cement mixing ............................................................... 42 7.2.4.4 Stone Columns ..................................................................... 43 7.2.4.5 Deep Dynamic Compaction .................................................. 43 7.2.5 Differential Settlement ....................................................................... 43 7.2.6 Next Steps ......................................................................................... 44 7.3 Foundations ................................................................................................... 44 7.3.1 Shallow Foundation Support .............................................................. 44 7.3.2 Driven Pile Foundations ..................................................................... 44 7.3.2.1 Vertical Load Capacity .......................................................... 45 7.3.2.2 Other Driven Pile Types and Sizes ....................................... 45 7.3.2.3 Lateral Load Capacity ........................................................... 46 7.3.2.4 Pile Installation ...................................................................... 46 7.3.2.5 Indicator Pile Driving ............................................................. 46 7.3.2.6 Approximate Cost of Driven Pile Foundations ...................... 47 7.3.3 Alternatives to Driven Pile Foundations ............................................. 47 7.3.4 Lateral Earth Pressures ..................................................................... 48 7.4 Geotechnical Observation ............................................................................. 48 8.0 GENERAL LIMITATIONS AND BASIS FOR RECOMMENDATIONS ....................... 49 9.0 REFERENCES .......................................................................................................... 50 Mare Island, California May 1, 2017 Page ii LIST OF FIGURES Figure 1 Site