Environmental Assessment

February 2006

The Project has made several design refinements as it has progressed through Preliminary Engineering, such as moving the Metrorail track to the median of Route 7 and shortening a tunnel in Tysons Corner.

The Federal Transit Administration has worked with the Project team to prepare an Environmental Assessment that describes the potential environmental effects that could result from these changes.

• Cover
• Abstract
• Table of Contents
• Chapter 1 - Purpose and Need for the Proposed Action
• Chapter 2 - Alternatives Evaluated
  • Figure 2-1: Key to Design Changes
  • Figure 2-2: Alignment Change from I-66 to Dulles Connector Road
  • Figure 2-3: Aerial Structure Types
  • Figure 2-4: Alignment Change in Tysons Corner
  • Figure 2-5: Proposed Cross-Section Changes along Route 7
  • Figure 2-6: Tysons East Station Plan Comparison
  • Figure 2-7: Tysons East Station Longitudinal Section
  • Figure 2-8: Tysons Central 123 Station Plan Comparison
  • Figure 2-9: Tysons Central 123 Station Longitudinal Section
  • Figure 2-10: Tysons Central 7 Station Plan Comparison
  • Figure 2-11: Tysons Central 7 Station Longitudinal Section
  • Figure 2-12: Tysons West Station Plan Comparison
  • Figure 2-13: Tysons West Station Longitudinal Section
  • Figure 2-14: Wiehle Avenue Station Plan Comparison
  • Figure 2-15: Wiehle Avenue Station Longitudinal Section
  • Figure 2-16: Changes to West Falls Church Rail Yard
  • Figure 2-17: Y-15 Yard Site: Proposed Phase I Construction Use
  • Figure 2-18: Proposed Stormwater Management Facilities
  • Figure 2-19: Potential Construction Staging Areas
• Chapter 3 - Environmental Effects
• Appendix A - List of Preparers
• Appendix B - Distribution List
• Appendix C - Summary of Effects