Birch Creek Floodplain Restoration Project (Draft
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Birch Creek Floodplain Restoration Project Draft Environmental Assessment August 2020 DOE/EA-2135 This page left blank intentionally Birch Creek Floodplain Restoration Project Draft Environmental Assessment TABLE OF CONTENTS Acronyms vi Chapter 1 Introduction 1-1 Background ................................................................................................................. 1-1 Purpose and Need ....................................................................................................... 1-3 Public Scoping and Key Issues ................................................................................... 1-3 Chapter 2 Alternatives 2-1 Proposed Action .......................................................................................................... 2-1 2.1.1 Main-Channel Realignment and Restoration ............................................................. 2-1 2.1.2 Improve Secondary Channel and Floodplain Interactions ......................................... 2-2 2.1.2.1 Install Habitat-Forming In-Stream Large-Wood Structures ...................................... 2-2 2.1.3 Wetland Creation ........................................................................................................ 2-3 2.1.4 Riparian and Upland Vegetation Planting ................................................................. 2-3 2.1.5 Temporary Staging Areas, Access Roads, and Water Crossings ................................ 2-4 2.1.6 New Groundwater Well and Removal of Existing Infrastructure ............................... 2-5 Construction Sequencing and Timing ......................................................................... 2-5 2.2.1 Construction Activities ................................................................................................ 2-5 2.2.2 Anticipated Construction Schedule and Phasing ........................................................ 2-6 No-Action Alternative.................................................................................................. 2-7 Comparison of the Alternatives ................................................................................... 2-7 Mitigation Measures ................................................................................................. 2-10 Chapter 3 Affected Environment and Environmental Consequences 3-1 Geology and Soils ....................................................................................................... 3-2 3.1.1 Affected Environment .................................................................................................. 3-2 3.1.1.1 Geology and Soils ....................................................................................................... 3-2 August 2020 Page i Birch Creek Floodplain Restoration Project Draft Environmental Assessment 3.1.2 Environmental Consequences – Proposed Action ...................................................... 3-2 3.1.3 Environmental Consequences – No Action ................................................................. 3-3 Vegetation ................................................................................................................... 3-3 3.2.1 Affected Environment .................................................................................................. 3-3 3.2.1.1 Vegetation ................................................................................................................... 3-3 3.2.2 Environmental Consequences – Proposed Action ...................................................... 3-8 3.2.3 Environmental Consequences – No Action ................................................................. 3-9 Water Resources.......................................................................................................... 3-9 3.3.1 Affected Environment .................................................................................................. 3-9 3.3.1.1 Water Quality .............................................................................................................. 3-9 3.3.1.2 Groundwater ............................................................................................................. 3-10 3.3.1.3 Wetlands and Floodplains ........................................................................................ 3-10 3.3.2 Environmental Consequences – Proposed Action .................................................... 3-11 3.3.2.1 Water Resources........................................................................................................ 3-11 3.3.2.2 Wetlands and Floodplains ........................................................................................ 3-14 3.3.3 Environmental Consequences – No Action ............................................................... 3-15 3.3.3.1 Water Quality ............................................................................................................ 3-15 3.3.3.2 Groundwater ............................................................................................................. 3-15 3.3.3.3 Wetlands and Floodplains ........................................................................................ 3-15 Fish and Aquatic Species .......................................................................................... 3-16 3.4.1 Affected Environment ................................................................................................ 3-16 3.4.1.1 General Fish and Aquatic Species ............................................................................ 3-16 3.4.1.2 Anadromous Species ................................................................................................. 3-16 3.4.1.3 Special Status Fish and Designated Critical Habitat within Affected Area ............. 3-17 3.4.2 Environmental Consequences – Proposed Action .................................................... 3-17 August 2020 Page ii Birch Creek Floodplain Restoration Project Draft Environmental Assessment 3.4.3 Environmental Consequences – No Action ............................................................... 3-18 Wildlife ...................................................................................................................... 3-19 3.5.1 Affected Environment ................................................................................................ 3-19 3.5.1.1 General Wildlife ........................................................................................................ 3-19 3.5.1.2 Introduced Upland Vegetation .................................................................................. 3-19 3.5.1.3 Riparian Vegetation .................................................................................................. 3-19 3.5.1.4 Cliffs, Caves, and Talus ............................................................................................ 3-20 3.5.1.5 Perennial Grassland ................................................................................................. 3-20 3.5.1.6 Introduced Wetlands ................................................................................................. 3-20 3.5.2 Special Status Wildlife............................................................................................... 3-20 3.5.3 Environmental Consequences – Proposed Action .................................................... 3-21 3.5.4 Environmental Consequences – No Action ............................................................... 3-22 Cultural Resources .................................................................................................... 3-22 3.6.1 Affected Environment ................................................................................................ 3-23 3.6.2 Environmental Consequences – Proposed Action .................................................... 3-24 3.6.3 Environmental Consequences – No Action ............................................................... 3-25 Land Use ................................................................................................................... 3-25 3.7.1 Affected Environment ................................................................................................ 3-25 3.7.2 Environmental Consequences – Proposed Action .................................................... 3-25 3.7.3 Environmental Consequences – No Action ............................................................... 3-25 Air Quality and Climate Change............................................................................... 3-26 3.8.1 Affected Environment ................................................................................................ 3-26 3.8.1.1 Air Quality ................................................................................................................. 3-26 3.8.1.2 Climate Change ......................................................................................................... 3-26 3.8.2 Environmental Consequences – Proposed Action .................................................... 3-27 August 2020 Page iii Birch Creek Floodplain Restoration Project Draft Environmental Assessment 3.8.2.1 Air Quality ................................................................................................................. 3-27 3.8.2.2 Climate Change ......................................................................................................... 3-27 3.8.3 Environmental Consequences – No Action ..............................................................