Document Type: EA-Administrativ e Record Index Field: Env ironmental Assessment Project Name: Oxf ord-Cof feeville 161-kV TL Project Number: 2017-15 OXFORD-COFFEEVILLE 161-KV TRANSMISSION LINE FINAL ENVIRONMENTAL ASSESSMENT Lafayette and Yalobusha Counties, Mississippi Prepared by: TENNESSEE VALLEY AUTHORITY Chattanooga, Tennessee February 2019 Direct Questions to: Anita E. Masters NEPA Program and Valley Projects Tennessee Valley Authority 1101 Market Street, BR 4A Chattanooga, Tennessee 37402 This page intentionally left blank Contents TABLE OF CONTENTS CHAPTER 1................................................................................................................................1 1.1 Proposed Action – Improve Power Supply ........................................................................ 1 1.2 Need for the Proposed Action .......................................................................................... 2 1.3 Decisions to be Made...................................................................................................... 5 1.4 Related Environmental Reviews or Documentation ........................................................... 5 1.5 Scoping Process and Public Involvement ......................................................................... 5 1.6 Issues to be Addressed ................................................................................................... 6 1.7 Necessary Federal Permits and Licens es ......................................................................... 7 CHAPTER 2.............................................................................................................................. 11 2.1 Alternatives ...................................................................................................................11 2.1.1 The No Action Alternative – TVA Does Not Provide a New Power Supply to the Northern Mississippi Area .................................................................................. 11 2.1.2 Action Alternative – TVA Provides a New Power Supply to the Northern Mississippi Service Area.......................................................................................... 12 2.1.3 Alternatives Considered but Eliminated from Further Discussion ................................. 12 2.1.3.1 Construction of a Coffeeville-North Oakland 161-kV Transmission Line ................. 12 2.1.3.2 Construction of an Interconnection with Entergy................................................... 12 2.1.3.3 Underground Utility Lines ................................................................................... 13 2.2 Construction, Operation, and Maintenance of the Proposed Transmission Line..................13 2.2.1 Transmission Line Construction ................................................................................ 13 2.2.1.1 Right-of-Way Acquisition and Clearing ................................................................ 13 2.2.1.2 Access Roads ................................................................................................... 15 2.2.1.3 Construction Assembly Areas ............................................................................. 15 2.2.1.4 Structures and Conductors ................................................................................. 18 2.2.1.5 Conductor and Ground Wire Installation .............................................................. 19 2.2.1.6 Proposed Substation Expansion ......................................................................... 19 2.2.2 Operation and Maintenance ..................................................................................... 21 Inspection ....................................................................................................................... 21 Vegetation Management .................................................................................................. 21 Structure Replacement..................................................................................................... 22 2.3 Siting Process ...............................................................................................................23 2.3.1 Definition of the Study Area ...................................................................................... 23 2.3.2 Description of the Study Area ................................................................................... 23 2.3.3 Data Collection ........................................................................................................ 24 2.3.4 Establishment and Application of Siting Criteria ......................................................... 24 2.3.5 Development of General Route Segments and Potential Transmission Line Routes ................................................................................................................... 25 Potential Transmission Line Corridors ............................................................................... 26 2.4 Identification of the Preferred Transmission Line Route ....................................................27 2.5 Comparison of Environmental Effects by Alternative ........................................................29 2.6 Identification of Mitigation Measures ...............................................................................31 2.7 The Preferred Alternative ...............................................................................................32 CHAPTER 3.............................................................................................................................. 33 3.1 Groundwater and Geology..............................................................................................33 3.2 Surface Water ...............................................................................................................34 3.3 Aquatic Ecology .............................................................................................................35 Environmental Assessment i Oxford-Coffeeville 161-kV Transmission Line 3.4 Vegetation.....................................................................................................................36 3.5 Wildlife ..........................................................................................................................38 3.6 Endangered and Threatened Species .............................................................................39 3.6.1 Aquatic Animals ....................................................................................................... 41 3.6.2 Plants ..................................................................................................................... 41 3.6.3 Terrestrial Animals ................................................................................................... 41 3.7 Floodplains....................................................................................................................43 3.8 Wetlands .......................................................................................................................43 3.9 Aesthetics .....................................................................................................................45 3.9.1 Visual Resources ..................................................................................................... 45 3.9.2 Noise and Odors ...................................................................................................... 47 3.10 Archaeologic al and Historic Resources ...........................................................................50 3.11 Recreation, Parks, and Natural Areas .............................................................................52 3.12 Socioeconomics and Environmental Justice ....................................................................55 CHAPTER 4.............................................................................................................................. 59 4.1 No Action Alternative .....................................................................................................59 4.2 Action Alternative...........................................................................................................59 4.2.1 Groundwater and Geology........................................................................................ 59 4.2.2 Surface Water ......................................................................................................... 60 4.2.3 Aquatic Ecology ....................................................................................................... 61 4.2.4 Vegetation............................................................................................................... 62 4.2.5 Wildlife .................................................................................................................... 63 4.2.6 Endangered and Threatened Species ....................................................................... 64 4.2.6.1 Aquatic Animals ................................................................................................. 64 4.2.6.2 Plants ............................................................................................................... 64 4.2.6.3 Terrestrial Animals ............................................................................................. 64 4.2.7 Floodplains.............................................................................................................. 66 4.2.8 Wetlands ................................................................................................................