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  1. Home
  2. Projects
  3. Studies
  4. I-70 Twin Tunnels Environmental Assessment
  5. Finding of No Significant Impact (FONSI)
Resources
  • Projects
  • Assets
  • Studies
    • 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
    • Ports to Plains
    • Region 3 Intersection Priority
    • Studies & Assessments
    • CO 119 Multi-modal Planning and Environmental Linkages Study
    • US 160-CR 225 Intersection Improvements
  • Central 70
  • Region 1 Denver Metro/Central Colorado Projects
  • Region 2 Southeastern Colorado Projects
  • Region 3 Northwestern Colorado Projects
  • Region 4 Northeastern Colorado Projects
  • Region 5 Southwestern Colorado Projects
  • CDOT Projects Overview
  • C470 - Wadsworth Boulevard to I-70 NEPA and Preliminary Design
  • I-25 (US 36 to 104th Ave) Improvements
  • 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
  • Teller County
  • US 50 Bonforte to Avondale Resurfacing
  • 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
  • I-70 Median Cable Rail in Eagle County
  • CO 115 Improvements - Colorado Springs to Penrose
  • CO 121/Wadsworth Signal Improvements in Jefferson County
  • Interstates
  • US Highways
  • State Highways
  • Denver Metro Area
  • Central/Eastern Colorado
  • Northeastern Colorado
  • Northwestern Colorado
  • Southeastern Colorado
  • Southwestern Colorado
  • I-70 Wildlife Fence in Eagle County
  • Southeastern Colorado Pavement Marking
  • CO 72 Frontage Road to Indiana Street Resurfacing
  • US 385 North of Cheyenne Wells
  • US 85 Corridor Improvements
  • US 550 Chipeta Traffic Signal Installation
  • CO 71 Bridge Repair Otero County
  • I-70 VSL and CO 74 & US 285 ITS Upgrades
  • I-76 Over Clear Creek Scour Mitigation
  • I-25 and CO-7: Interim Transit Improvements
  • CO 119 Boulder Canyon Tunnel Repairs
  • Clear Creek Scour Mitigation on I-70
  • I-70 Salt Wash Bridges Scour, Mesa County
  • US 34 Brush Lateral Canal Repair
  • C-470 Trail Bridge over Acres Green
  • US 287 & CO 52 Intersection Safety Improvements
  • I-25 & Alameda Bridge Replacement
  • I-70 Bridges over Ward Road
  • I-25 Concrete Panel Replacement
  • I-25 Walsenburg Bridge Replacement
  • Firestone-Longmont Mobility Hub
  • CO 12 Bridge Replacement in Las Animas County
  • CO 115 in Fremont County and US 50 in Pueblo County Sign Replacement
  • CO 207 & CO 266 Resurfacing
  • CO 74 Evergreen Lake North Trail
  • CO 109 Bridge over US 50, BNSF Railroad
  • US 24 Woodland Park Paving and ADA Curb Ramp Improvements
  • CO 21 and US 24 Signal Improvement Project in El Paso County
  • US 50 Passing Lane - Gunnison County
  • CO 172 Ignacio Resurfacing
  • US 50 & CO 71 Intersection Improvements
  • US 385 Holyoke North Resurfacing
  • CO 170 Critical Culverts, Boulder County
  • Drew Dix Parkway Dillon Drive at I-25 Interchange
  • Metro Denver Bridge Deck Safety Project
  • Southeast Colorado Guardrail Replacement
  • I-25 Resurfacing North of Walsenburg Project
  • CO 93 Resurfacing between US 6 and 58th Ave
  • I-70 Bridge Maintenance between Limon and Agate
  • US 6 & 20 Road Intersection Improvements
  • I-70 Concrete Slab Replacement from West Rifle to Silt
  • CO 64 Bridges west of Meeker
  • US 24 Curve Correction in Teller County
  • US 160 Priority Culverts in Southwestern Colorado
  • CO 318 Resurfacing Project Moffat County
  • US 285/CO 9 Intersection Improvements & Bridge Replacement
  • I-70 East of DeBeque Resurfacing
  • CO 114 Overlay, Gunnison to Saguache County
  • CO 64 & CO 13 Meeker Resurfacing Project
  • CO 133 Rockfall Project North of McClure Pass to South of Carbondale
  • CO 9 Surface Treatment in Summit and Grand County
  • US 160 Cortez Signal Improvements
  • CO 96 Overlay between Eads and Sheridan Lake
  • CO 2/CO 88/US 285 Denver Metro ADA Ramps
  • US 160 Pagosa West Resurfacing
  • ADA Ramp Project on US 6 & South Frontage Road in Eagle and Vail
  • US 36 Surface and Safety Improvements between Boulder and Lyons
  • I-70 Bridge Over Washington Street
  • CO 257 Resurfacing US 34 Business to Walnut Street
  • CO 71 Passing Lane Construction from Limon to Brush
  • CO 67 Safety Improvements in Douglas & Teller Counties
  • US 85 at WCR 66 Acceleration Lanes in North Greeley
  • CO 83 Resurfacing in Douglas County
  • Southwest Colorado Pavement Marking
  • CO 92 Chip Seal Project in Montrose and Delta County
  • US 50 Cañon City Road Maintenance
  • CO 138 Logan County Widening Project
  • US 85 Platteville Resurfacing Between CO 60 and CO 66
  • CO 14 and US 40 Crack Sealing in Jackson and Grand Counties
  • CDOT Retaining Wall Improvements in Jefferson County
  • CO 133 Culvert Repair in Bowie, CO
  • CO 13 Chip Seal North of Craig
  • Preventative Maintenance of I-25 bridges at 58th and 62nd
  • CO 71 Overlay between Ordway and Punkin Center
  • CO 121 Signal Improvements in Jefferson County
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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