Final Environmental Impact Statement to Consider a Highway Right-of-Way, Amended Habitat Conservation Plan and Issuance of an Incidental Take Permit for the Mojave Desert Tortoise, and Proposed Resource Management Plan Amendments, Washington County, UT November 2020 Volume 2: Chapters 1 – 4 Estimated Total Lead Agencies’ Costs Associated with Developing and Producing this Document: $8,275,620 Table of Contents Chapter 1. Purpose and Need for Action ....................................................................................... 1-1 1.1 Introduction .................................................................................................................. 1-1 1.2 Applicants’ Objectives .................................................................................................. 1-2 1.2.1 Right-of-way Applicant’s Objectives ............................................................. 1-2 1.2.2 Incidental Take Permit Applicant’s Objectives ............................................ 1-2 1.3 Purpose and Need for Federal Actions........................................................................ 1-2 1.3.1 Right-of-way Application and Red Cliffs National Conservation Area Resource Management Plan Amendment ................................................... 1-3 1.3.2 Issuance of Incidental Take Permit and Amended Habitat Conservation Plan ................................................................................................................ 1-3 1.3.3 St. George Field Office Resource Management Plan Amendment ............. 1-4 1.4 Federal Decisions ......................................................................................................... 1-4 1.5 Issues and Related Resource Topics Identified through Scoping .............................. 1-4 1.5.1 Issues Analyzed in Detail in the Environmental Impact Statement ........... 1-5 1.5.2 Issues Considered but Not Analyzed in Detail ............................................. 1-5 1.6 Changes between the Draft EIS and RMP Amendments and the Final EIS and Proposed RMP Amendments ....................................................................................... 1-8 Chapter 2. Proposed Action and Alternatives ............................................................................... 2-1 2.1 Alternative Development ............................................................................................. 2-1 2.2 Northern Corridor Highway .......................................................................................... 2-2 2.2.1 Northern Corridor: No Action Alternative ..................................................... 2-3 2.2.2 Northern Corridor: T-Bone Mesa Alignment ................................................. 2-4 2.2.3 Northern Corridor: UDOT Application Alignment .......................................... 2-4 2.2.4 Northern Corridor: Southern Alignment........................................................ 2-4 2.2.5 Red Hills Parkway Expressway...................................................................... 2-4 2.2.6 St. George Boulevard/100 South One-way Couplet ..................................... 2-5 2.2.7 Plan of Development ..................................................................................... 2-5 2.2.8 Construction and Phasing ............................................................................. 2-6 2.2.9 Avoidance, Minimization, and Mitigation Measures .................................... 2-6 2.3 Red Cliffs National Conservation Area Resource Management Plan Amendments . 2-9 2.4 Washington County Habitat Conservation Plan and Incidental Take Permit .......... 2-10 2.4.1 Habitat Conservation Plan and Incidental Take Permit No Action Alternative ................................................................................................... 2-13 2.4.2 Habitat Conservation Plan and Incidental Take Permit Action Alternative – Issue Incidental Take Permit subject to Mojave Desert Tortoise Conservation Measures in Amended HCP .................................................. 2-13 Northern Corridor – Highway Right-of-Way, Issuance of an Incidental Take Permit i Final EIS and Proposed RMP Amendments Table of Contents 2.5 St. George Field Office Resource Management Plan Amendments ........................ 2-23 2.6 Alternatives for Analysis ............................................................................................ 2-31 2.6.1 Alternative 1 – No Action Alternative ......................................................... 2-32 2.6.2 Alternative 2 – T-Bone Mesa Alignment for the Northern Corridor ........... 2-32 2.6.3 Alternative 3 – UDOT Application Alignment for the Northern Corridor ... 2-32 2.6.4 Alternative 4 – Southern Alignment for the Northern Corridor ................. 2-32 2.6.5 Alternative 5 – Red Hills Parkway Expressway for the Northern Corridor 2-32 2.6.6 Alternative 6 – St. George Boulevard/100 South One-way Couplet for the Northern Corridor .................................................................................. 2-32 2.7 Alternatives Considered but Eliminated from Detailed Analysis ............................. 2-33 2.7.1 Northern Corridor Highway Alternatives Considered but Eliminated ........ 2-33 2.7.2 Red Cliffs NCA RMP Amendment Alternatives Considered but Eliminated .................................................................................................... 2-36 2.7.3 Washington County Habitat Conservation Plan and Incidental Take Permit .......................................................................................................... 2-37 2.7.4 St. George Field Office RMP Amendment Alternatives Considered but Eliminated .................................................................................................... 2-37 Chapter 3. Affected Environment and Environmental Consequences ......................................... 3-1 3.1 Introduction .................................................................................................................. 3-1 3.1.1 Background .................................................................................................... 3-1 3.1.2 Analysis Methods and Assumptions ............................................................. 3-1 3.2 Vegetative Communities Including Noxious Weeds and Invasive Species ................ 3-6 3.2.1 Affected Environment .................................................................................... 3-6 3.2.2 Environmental Consequences ..................................................................... 3-10 3.3 Special Status Plants ................................................................................................. 3-19 3.3.1 Affected Environment .................................................................................. 3-19 3.3.2 Environmental Consequences ..................................................................... 3-27 3.4 General Wildlife .......................................................................................................... 3-37 3.4.1 Affected Environment .................................................................................. 3-37 3.4.2 Environmental Consequences ..................................................................... 3-39 3.5 Special Status Wildlife ............................................................................................... 3-42 3.5.1 Affected Environment .................................................................................. 3-42 3.5.2 Environmental Consequences ..................................................................... 3-69 3.6 Endangered Species Act Section 6 Land Acquisition Grants ................................... 3-94 3.6.1 Affected Environment .................................................................................. 3-94 3.6.2 Environmental Consequences ..................................................................... 3-95 3.7 Geology, Mineral Resources, and Soils ................................................................... 3-102 3.7.1 Affected Environment ................................................................................ 3-102 ii Northern Corridor – Highway Right-of-Way, Issuance of an Incidental Take Permit Final EIS and Proposed RMP Amendments Table of Contents 3.7.2 Environmental Consequences ................................................................... 3-104 3.8 Paleontology ............................................................................................................. 3-107 3.8.1 Affected Environment ................................................................................ 3-107 3.8.2 Environmental Consequences ................................................................... 3-107 3.9 Prime and Unique Farmland .................................................................................... 3-109 3.9.1 Affected Environment ................................................................................ 3-109 3.9.2 Environmental Consequences ................................................................... 3-109 3.10 Wetlands, Floodplains, and Waters of the U.S. ...................................................... 3-110 3.10.1 Affected Environment ................................................................................ 3-110 3.10.2 Environmental Consequences ................................................................... 3-111 3.11 Water Resources .....................................................................................................