Paramount Boulevard/ Imperial Highway Intersection Improvement Project Initial Study/ Mitigated Negative Declaration April 2020 Lead Agency: City of Downey 11111 Brookshire Avenue Downey, CA 91790 Prepared by: Hodge & Associates 45-300 Portola Avenue, #2842 Palm Desert, CA 92261 Initial Study/Mitigated Negative Declaration Paramount Boulevard/Imperial Highway Intersection Improvement Project Table of Contents CEQA Appendix G: Environmental Checklist Form ..................................................................................................................... 1 I. Aesthetics ......................................................................................................................................................................................... 7 II. Agriculture and Forestry Resources ..................................................................................................................................... 8 III. Air Quality ..................................................................................................................................................................................... 10 IV. Biological Resources ................................................................................................................................................................. 25 V. Cultural Resources .................................................................................................................................................................... 27 VI. Energy ............................................................................................................................................................................................. 28 VII. Geology and Soils ....................................................................................................................................................................... 29 VIII. Greenhouse Gas Emissions .................................................................................................................................................... 31 IX. Hazards and Hazardous Materials ...................................................................................................................................... 34 X. Hydrology and Water Quality ............................................................................................................................................... 36 XI. Land Use and Planning ............................................................................................................................................................ 39 XII. Mineral Resources ..................................................................................................................................................................... 40 XIII. Noise ................................................................................................................................................................................................ 41 XIV. Population and Housing .......................................................................................................................................................... 49 XV. Public Services............................................................................................................................................................................. 50 XVI. Recreation ..................................................................................................................................................................................... 52 XVII. Transportation ............................................................................................................................................................................ 53 XVIII. Tribal Cultural Resources ....................................................................................................................................................... 55 XIX. Utilities and Service Systems ................................................................................................................................................ 56 XX. Wildfire ........................................................................................................................................................................................... 58 XXI. Mandatory Findings of Significance ................................................................................................................................... 59 Exhibits Exhibit 1 – Regional Location Map ..................................................................................................................................................... 3 Exhibit 2 – Project Vicinity Map .......................................................................................................................................................... 4 Tables Table 1 – Ambient Air Quality Standards ..................................................................................................................................... 12 Table 2 – Health Effects of Major Criteria Pollutants .............................................................................................................. 14 Table 3 – Air Quality Monitoring Summary (2014-2018), Number of Days Standards Were Exceeded and Maximum Levels During Such Violations.......................................................................................................... 17 Table 4 – South Coast Air Basin Emissions Forecasts (Emissions in tons/day).......................................................... 17 Table 5 – Daily Emissions Thresholds ........................................................................................................................................... 19 Table 6 – Construction Activity Equipment Fleet ..................................................................................................................... 21 Table 7 – Construction Activity Emissions , Maximum Daily Emissions (pounds/day) .......................................... 21 Table 8 – LST and Project Emissions (pounds/day) ............................................................................................................... 22 Table 9 – Construction Emissions (Metric Tons CO2e) .......................................................................................................... 33 Table 10 – Downey Land Use Compatibility Guidelines for Exterior Community Noise ......................................... 42 Table 11 – Human Response to Transient Vibration .............................................................................................................. 44 Table 12 – Estimated Vibration Levels During Project Construction .............................................................................. 45 Table 13 – Traffic Noise Impact Analysis, dBA CNEL at 50 feet from centerline ........................................................ 46 Table 14 – Construction Equipment Noise Levels .................................................................................................................... 47 Appendices Appendix A – Air Quality and GHG Impact Analysis Appendix B – Archaeological Assessment Appendix C – Noise Impact Analysis Appendix D – Mitigation Monitoring and Reporting Program Summary iii Initial Study/Mitigated Negative Declaration Paramount Boulevard/Imperial Highway Intersection Improvement Project CEQA Appendix G: Environmental Checklist Form 1. Project Title: Paramount Boulevard/Imperial Highway Intersection Improvement Project 2. Lead Agency Name and Address: City of Downey 1111 Brookshire Avenue Downey, CA 91790 3. Contact Person and Phone Number: Staff Contact: Edwin Norris, PE Public Works Division, Planning Division Phone Number: (626) 939-8425 4. Project Location: Paramount Boulevard/Imperial Highway Intersection Downey, CA 91791 5. Project Sponsor’s Name and Address: City of Downey 1111 Brookshire Avenue Downey, CA 91790 6. General Plan Designation: Public Right of Way; surrounding properties have a land use designation of General Commercial. 7. Zoning: Public Right of Way; surrounding properties are General Commercial. 8. Description of the project: The Paramount Boulevard and Imperial Highway Intersection Project calls for a re-design of the intersection to accommodate anticipated growth in traffic through 2035. Dual left turn pockets will be added in the southbound direction along Paramount Boulevard and in the westbound direction along Imperial Highway. All four legs of the intersection will be widened to provide sufficient road width for vehicular U-turn movements. The Project includes reconstruction of all four legs of the intersection with concrete pavement for 300 feet on all approaches and 100 feet for all departures. The intersection itself will be reconstructed with concrete pavement, and decorative concrete crosswalks will be added along with modified traffic signals and striping, signing, and pavement markings, street lighting, and upgraded bus shelters and furnishings. Partial right of way acquisition will be required along Imperial Highway and Paramount Boulevard on all four legs of the intersection. Some utility relocations and adjustments will be required to facilitate Project construction. 9. Surrounding Land Uses and Setting: The site is located in the southwestern portion of the City of Downey north of Interstate 105 (I-105) and east of Interstate 710 (I-710). The