Interstate 5 Improvement Project
(I-405 to SR-55)

The California Department of Transportation (Caltrans) District 12, in cooperation with the Orange County Transportation Authority (OCTA), proposes to widen Interstate 5 (I-5) between Interstate 405 (I-405) and State Route 55 (SR-55. the project limits on I-5 extend from approximately 0.4 mile (mi) north of the I-5/I-405 Interchange (Post Mile [PM] 21.3) to 0.2 mi south of SR-55 (PM 30.3) in Orange County, California. The project purpose is to reduce traffic congestion by improving traffic operations and meeting existing and future traffic demands.

Information in the Inital Study/Environmental Assessment (IS/EA) focuses on the environmental impact evaluation and proposed avoidance, minimization and/or mitigation of potential impacts associated with the proposed Build Alternatives.

Anticipated Schedule:
Project Approval & Environmental Document – December 2018
Design – July 2022
Construction – Feburary 2026

Public Notice

Initial Study with Proposed Mitigated Negative Declaration/Environmental Assessment

Cover page/General Information/Title Page/Proposed Mitigated Negative Declaration
Table of Contents

CHAPTER 1 - Proposed Project
 Affected Environment, Environmental Consequences, and Avoidance,
Minimization, and/or Mitigation Measures

2.1 Land Use
2.2 Growth
2.3 Community Impacts
2.4 Utilities and Emergency Services
2.5 Traffic and Transportation/Pedestrian and Bicycle Facilities
2.6 Visual/Aesthetics
2.7 Cultural Resources
2.8 Hydrology and Floodplain
2.9 Water Quality and Storm Water Runoff
2.10 Geology/Soils/Seismic/Topography
2.11 Paleontology
2.12 Hazardous Waste/Materials
2.13 Air Quality
2.14 Noise
2.15 Natural Communities
2.16 Wetlands and Other Waters
2.17 Plant Species
2.18 Animal Species
2.19 Invasive Species
2.20 Cumulative Impacts
CHAPTER 3 - CEQA Checklist
CHAPTER 4 - Comments and Coordination
CHAPTER 5 - List of Preparers
CHAPTER 6 - Distribution List

Appendix A - Draft Section 4(f) De Minimis Finding and Resources Evaluated Relative to Requirements of Section 4(f)
Appendix B - Title VI Policy Statement
Appendix C - Summary of Relocation Benefits
Appendix D - 2016 RTP and 2017 FTIP Project Listings
Appendix E - Environmental Commitments Record
Appendix F - Acronyms and Abbreviations
Appendix G - List of Technical Studies
Appendix H - References
Appendix I - FEMA FIRM Maps
Appendix J - Noise Table and Figures

Air Quality Assessment Report (March 2017)
Draft Relocation Impact Statement (November 2017)
Phase I Initial Site Assessment (October 2017)
Location Hydraulic Study (March 2017)
Natural Environment Study (May 2017)/Jurisdictional Delineation (February 2017)
Noise Abatement Decision Report (February 2018)
Noise Study Report (June 2017)
Paleontological Identification Report and Paleontological Evaluation Report (February 2017)
Revised District Preliminary Geotechnical Report (February 2017)
Final Traffic/Circulation Impact Report (January 2017)
Visual Impact Assessment (June 2017)
Water Quality Assessment Report (April 2017)

Build Alternatives (Alternative 2 Design Variation A & B - Including Design Option 3) Layout Plan Sheets

Please submit your comments in writing no later than 5 pm, June 8 2018 to Brian Liu, Associate Environmental Planner, California Department of Transportation, District 12, Environmental Analysis, 1750 East 4th Street, Santa Ana, CA 92705 or via e-mail to:

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