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  1. Home
  2. Projects
  3. Studies
  4. I-70 Twin Tunnels Environmental Assessment
  5. Finding of No Significant Impact (FONSI)
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    • US 24 West Finding of No Significant Impact (FONSI)
    • North I-25 PEL Study, US 36 to CO 7
    • US 34 & US 85 Interchange PEL Study
    • I-25 and Arapahoe Road/SH 88 Interchange Environmental Assessment & FONSI
    • I-25 Colorado Springs Area Finding of No Significant Impact (FONSI)
    • CO 7 Cherryvale to 75th Street EA & FONSI
    • US 34, US 287 to Larimer County Rd. 3 EA and FONSI
    • US 36 Managed Lanes - Investment Grade Traffic and Revenue Study
    • South I-25 Corridor and US 85 Corridor FEIS & ROD
    • US 6 - 24 Road to SH 139 Access Control Plan
    • US 6/River Front Road Access Control Plan in Silt
    • 2009 Disparity Study and Appendices
    • I-25 Valley Highway Environmental Impact Statement (EIS) and ROD
    • I-25, Colorado Springs to Monument Environmental Assessment
    • SH 42 Planning and Environmental Linkage Study (PEL)
    • US 40 Section 4(f) Evaluation
    • US 50 West Wills Blvd to McCulloch Blvd EA
    • US 50 West PEL Study
    • SH 60 Access Control Plan
    • SH 60 Environmental Overview Study
    • I-70/32nd Avenue Interchange Environmental Assessment
    • I-70 Mountain Corridor Mobility and Operational Assessment
    • I-70 Mountain Corridor Short Term Mobility Solutions Report
    • I-70 Reversible Lane Study
    • I-70 Reversible (Zipper) Lane Study Phase II
    • I-70 Twin Tunnels Environmental Assessment
      • Finding of No Significant Impact (FONSI)
    • SH 88/Federal Boulevard Environmental Assessment and FONSI
    • SH 133 Carbondale Access Control Plan
    • US 160 Durango to Bayfield Final EIS
    • US 160 Durango to Bayfield ROD October 2006
    • US 285 Environmental Assessment with Appendices
    • US 287 at Lamar Environmental Assessment and FONSI
    • US 287 Loveland to Fort Collins Environmental Overview Study (EOS)
    • US 287 from CO 1 to the LaPorte Bypass EA and FONSI
    • US 385 High Plains Corridor
    • SH 402 EA and FONSI
    • C-470 Environmental Assessment & FONSI 2015
    • Denver Area Regional Bus Facility Study
    • Devolution Study Report
    • Eastern Colorado Mobility Study
    • Northwest Corridor EIS
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    • Region 3 Intersection Priority
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  • CDOT Projects Overview
  • C470 - Wadsworth Boulevard to I-70 NEPA and Preliminary Design
  • I-25 (US 36 to 104th Ave) Improvements
  • CO 7 Lower (Lyons to Raymond)
  • Santa Fe Drive Action Plan- A Planning & Environmental Linkages (PEL) Study | C-470 to I-25
  • Southeastern Colorado Bridge Bundle Project
  • I-270 Corridor Improvements
  • Southeastern CO Centerline Rumble Strip Installation
  • Northeastern Colorado Bridge Rehabilitation in Boulder County
  • Teller County
  • US 50 Bonforte to Avondale Resurfacing
  • Weld County ADA Ramps
  • US 285 Resurfacing between Monte Vista and Saguache
  • US 50 La Junta Microsurfacing
  • CO 82 - Paepcke Transit Hub Improvements in the City of Aspen on Main and Galena
  • Park County Chain-Up Stations
  • Eisenhower-Johnson Memorial Tunnels Infrastructure Repairs
  • ITS Installation of Road Side Connected Vehicles
  • CO 139 Douglas Pass Resurfacing Project
  • CO 133 Bowie Chip Seal
  • CO 1 Wellington South Resurfacing
  • I-70 Median Cable Rail in Eagle County
  • CO 115 Improvements - Colorado Springs to Penrose
  • CO 52 and Weld County Road 37 Intersection Improvements
  • CO 121/Wadsworth Signal Improvements in Jefferson County
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  • I-70 Wildlife Fence in Eagle County
  • CO 72 Chipseal in Larimer County
  • CO 71 Passing Lane Construction from Limon to Brush
  • Southeastern Colorado Pavement Marking
  • US 85 & Meadows Parkway Culvert Rehabilitation
  • CO 72 Frontage Road to Indiana Street Resurfacing
  • US 50 - Monarch Pass Emergency Truck Ramp Repair
  • Denver Metro Bridge Safety Improvements
  • US 385 North of Cheyenne Wells
  • I-25 Dry Creek Ramp Improvements
  • I-70 Wrong Way Detection Maintenance
  • US 85 Corridor Improvements
  • US 550 Chipeta Traffic Signal Installation
  • US 40 - Colfax and Quail Signal Replacement
  • CO 71 Bridge Repair Otero County
  • I-70 VSL and CO 74 & US 285 ITS Upgrades
  • US 160-CR 225 Intersection Improvements
  • I-76 Over Clear Creek Scour Mitigation
  • I-25 and CO-7: Interim Transit Improvements
  • CO 119 Boulder Canyon Tunnel Repairs
  • CO 52 Culvert Extension at Weld County Road 19
  • Clear Creek Scour Mitigation on I-70
  • I-70 Salt Wash Bridges Scour, Mesa County
  • US 34 Brush Lateral Canal Repair
Finding of No Significant Impact (FONSI) https://www.codot.gov/projects/studies/i70twintunnels-environmental-assessment/finding-of-no-significant-impact-fonsi https://www.codot.gov/@@site-logo/siteLogo.png

Finding of No Significant Impact (FONSI)

TT-FONSI Complete Document
TT-FONSI Front Matter
TT-FONSI Chapter 1
TT-FONSI Chapter 2
TT-FONSI Chapter 3
TT-FONSI Chapter 4
TT-FONSI Chapter 5
TT-FONSI Chapter 6
TT-FONSI Chapter 7
TT-FONSI Chapter 8
Tags:
  • Project: I-70 Twin Tunnels
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