Route 710 Tunnel Technical Feasibility Assessment Report Task Order PS-4310-1268-05-01-2 Submitted to: Los Angeles County Metropolitan Transportation Authority One Gateway Plaza Los Angeles, CA 90026 MS 99-22-8 Submitted by: June 7, 2006 Table of Contents TABLE OF CONTENTS TABLE OF CONTENTS ES 1.0 Executive Summary...................................................................................................... 1 ES 1.1 Project Background.................................................................................................. 1 ES 1.2 Tunnel Technical Feasibility Assessment ............................................................... 1 ES 1.3 Tunnel Technical Feasibility Assessment – Findings ............................................ 3 ES 1.4 Physical Feasibility.................................................................................................... 3 ES 1.4.1 Tunneling Technologies...................................................................................... 4 ES 1.4.2 Physical Characteristics ...................................................................................... 5 ES 1.4.3 Traffic Demand................................................................................................... 5 ES 1.5 Environmental/Social Feasibility............................................................................. 6 ES 1.6Financial Feasibility....................................................................................................... 6 ES 1.7 Conclusion ................................................................................................................. 6 1.0 Introduction................................................................................................................... 1 1.1 Project Background...................................................................................................... 1 1.2 Project History .............................................................................................................. 1 1.3 MTA Team .................................................................................................................... 3 1.4 MTA Tunnel Advisory Panel....................................................................................... 3 1.5 MTA Working Group .................................................................................................. 3 1.6 Study Goals and Objectives ......................................................................................... 4 2.0 Summary of Large Highway Tunnels Domestic and International ......................... 5 2.1 A-86 Tunnel, Malmaison, France................................................................................ 6 2.2 M30 Project Madrid, Spain ......................................................................................... 8 2.3 Mt. Baker Ridge Tunnel, Seattle, Washington........................................................... 9 3.0 Geotechnical Evaluation............................................................................................. 13 3.1 Regional Geology and Tectonics................................................................................ 13 3.2 Site Geology ................................................................................................................. 13 3.3 Stratigraphy and Structure........................................................................................ 15 3.3.1 Crystalline Basement Rock................................................................................... 15 3.3.2 Topanga Formation............................................................................................... 15 3.3.3 Monterey/Puente Formation ................................................................................. 21 3.3.4 Unnamed Shale ..................................................................................................... 21 3.3.5 Fernando Formation.............................................................................................. 21 3.3.6 Quaternary Alluvium ............................................................................................ 21 i Route 710 Tunnel Technical Feasibility Assessment Report Table of Contents 3.4 Faults............................................................................................................................ 22 3.4.1 Sierra Madre Fault ................................................................................................ 22 3.4.2 Santa Monica-Hollywood Fault System ............................................................... 22 3.4.3 Raymond Hill Fault............................................................................................... 23 3.4.4 York Boulevard Fault ........................................................................................... 23 3.4.5 Eagle Rock Fault................................................................................................... 23 3.5 Local Seismicity........................................................................................................... 23 3.6 Structure Along Tunnel Study Alignment................................................................ 24 3.7 Site Exploration and Testing in 2006 ........................................................................ 25 3.7.1 Field Exploration for Feasibility Study................................................................. 25 3.7.2 Testing................................................................................................................... 25 3.7.2.1 Soil Properties................................................................................................... 26 3.7.2.2 Rock properties ................................................................................................. 26 3.8 Groundwater ............................................................................................................... 28 3.9 Subsurface Gas............................................................................................................ 29 3.10 Feasibility for Tunneling ............................................................................................ 29 3.11 Additional Exploration and Testing.......................................................................... 30 4.0 Tunneling Technologies.............................................................................................. 31 4.1 Introduction................................................................................................................. 31 4.2 Tunnel Conditions and Requirements ...................................................................... 31 4.2.1 Horizontal Alignment and Controls...................................................................... 31 4.2.2 Vertical Alignment and Controls.......................................................................... 31 4.2.3 Tunnel Cross Sectional Requirements.................................................................. 32 4.2.4 Cross-passages and Shafts .................................................................................... 32 4.2.5 Geologic and Groundwater Conditions ................................................................ 32 4.3 Tunneling Methods ..................................................................................................... 33 4.3.1 Tunnel Boring Machines....................................................................................... 33 4.3.2 Sequential Excavation Methods............................................................................ 38 4.3.3 Fault Crossings...................................................................................................... 41 4.3.4 Undergound Ventilation Buildings and Shafts ..................................................... 42 4.3.5 Hauling of Soil...................................................................................................... 42 4.3.6 Protection of Adjacent Structures ......................................................................... 43 4.3.7 Instrumentation and Monitoring ........................................................................... 44 4.3.8 Summary............................................................................................................... 44 4.4 Tunnel Ventilation ...................................................................................................... 45 4.4.1 Ventilation System Types..................................................................................... 45 4.4.2 Air Cleaning Technology...................................................................................... 46 4.4.3 Tunnel Alternatives............................................................................................... 47 4.4.4 Criteria .................................................................................................................. 47 4.4.5 Analysis Approach................................................................................................ 48 ii Route 710 Tunnel Technical Feasibility Assessment Report Table of Contents 4.4.6 Analysis................................................................................................................. 49 4.4.7 Ventilation Installation.......................................................................................... 50 5.0 Traffic Modeling / Traffic Analysis..........................................................................