_________________________________________ FINAL ENVIRONMENTAL ASSESSMENT VOLUME I _________________________________________ Replacement Passenger Terminal and Enabling Projects Des Moines International Airport Des Moines, Iowa Prepared for Des Moines Airport Authority And U.S. Department of Transportation Federal Aviation Administration As lead Federal Agency pursuant to the National Environmental Policy Act of 1969 Prepared by: RS&H Iowa, P.C. June 2019 This Environmental Assessment becomes a Federal document when evaluated, signed and dated by the Responsible Federal Official. ___________________________________ _________________ Responsible Federal Official Date THIS PAGE INTENTIONALLY LEFT BLANK TABLE OF CONTENTS TABLE OF CONTENTS VOLUME I Chapter 1 Introduction and Proposed Action ...................................................................................................................... 1-1 1.1 Airport Overview ......................................................................................................................................................... 1-1 1.2 Passenger Terminal Building Background ........................................................................................................ 1-4 1.3 Proposed Action .......................................................................................................................................................... 1-5 1.3.1 Phasing ..................................................................................................................................................................... 1-11 1.4 Requested Federal Actions .................................................................................................................................... 1-11 1.5 Document Organization ......................................................................................................................................... 1-12 Chapter 2 Purpose and Need ..................................................................................................................................................... 2-1 2.1 Background ................................................................................................................................................................... 2-1 2.1.1 Aviation Activity ...................................................................................................................................................... 2-1 2.2 Purpose of and need for the proposed action ................................................................................................ 2-1 2.2.1 Purpose For the Proposed Action ................................................................................................................... 2-2 2.2.2 Need for the Proposed Action .......................................................................................................................... 2-3 Chapter 3 Alternatives ................................................................................................................................................................... 3-1 3.1 Alternatives Screening Process .............................................................................................................................. 3-1 3.1.1 Level 1 Screening: Purpose and Need ........................................................................................................... 3-1 3.1.2 Level 2 Screening: Constructability, Cost, Airfield Safety, and Operational Functionality ........ 3-2 3.2 Comparison of Alternatives .................................................................................................................................... 3-2 3.2.1 Alternative 1: North Concept Alternative ..................................................................................................... 3-4 3.2.2 Alternative 2: East Concept Alternative ......................................................................................................... 3-4 3.2.3 Alternative 3: Refurbish Existing Terminal Building Alternative .......................................................... 3-4 3.2.4 Alternative 4: South Concept Alternative ..................................................................................................... 3-5 3.2.5 Alternative 5: No Action Alternative ............................................................................................................... 3-5 3.3 Alternatives Carried Forward for Analysis in This EA .................................................................................... 3-6 3.3.1 Alternative 2: East Concept Alternative ......................................................................................................... 3-6 3.3.2 Alternative 5: No Action Alternative ............................................................................................................... 3-6 Chapter 4 Affected Environment ............................................................................................................................................... 4-1 4.1 Study Areas .................................................................................................................................................................... 4-1 4.1.1 Project Study Area ................................................................................................................................................. 4-1 4.1.2 Regional Study Area ............................................................................................................................................. 4-1 4.2 Analysis Year ................................................................................................................................................................. 4-2 4.3 Resources Not Affected by the Proposed Action .......................................................................................... 4-2 Des Moines International Airport Replacement Passenger Terminal Final EA i TABLE OF CONTENTS 4.3.1 Coastal Resources .................................................................................................................................................. 4-2 4.3.2 Wild and Scenic Rivers (Water Resources) ................................................................................................... 4-2 4.4 Potentially Affected Environmental Resources ............................................................................................... 4-4 4.4.1 Air Quality ................................................................................................................................................................. 4-4 4.4.2 Biological Resources ............................................................................................................................................. 4-4 4.4.3 Climate ....................................................................................................................................................................... 4-6 4.4.4 Department of Transportation Act, Section 4(f) ........................................................................................ 4-8 4.4.5 Farmlands .................................................................................................................................................................. 4-8 4.4.6 Hazardous Materials, Solid Waste, and Pollution Prevention ............................................................ 4-10 4.4.7 Historical, Architectural, Archaeological, and Cultural Resources .................................................... 4-17 4.4.8 Land Use .................................................................................................................................................................. 4-25 4.4.9 Natural Resources and Energy Supply ........................................................................................................ 4-26 4.4.10 Noise and Noise-Compatible Land Use ................................................................................................. 4-27 4.4.11 Socioeconomics, Environmental Justice, and Children’s Environmental Health and Safety Risks ................................................................................................................................................................................ 4-31 4.4.12 Visual Effects ..................................................................................................................................................... 4-36 4.4.13 Water Resources ............................................................................................................................................. 4-36 4.5 Past, Present, and Reasonably Foreseeable Actions ................................................................................... 4-41 Chapter 5 Environmental Consequences ............................................................................................................................... 5-1 5.1 Air Quality ...................................................................................................................................................................... 5-1 5.1.1 Significance Threshold ......................................................................................................................................... 5-1 5.1.2 Methodology ..........................................................................................................................................................