SOLAR FARM ENVIRONMENTAL ASSESSMENT PINE RIDGE INDIAN RESERVATION United States Department of the Interior Bureau of Indian Affairs Great Plains Regional Office Aberdeen, South Dakota Prepared for: Bureau of Indian Affairs Aberdeen, South Dakota Prepared by: Trihydro Corporation Laramie, Wyoming on behalf of Hidden Water, Inc. Wichita, Kansas June 2016 For information contact: Bureau of Indian Affairs, Great Plains Regional Office 115 Fourth Avenue S.E. Suite 400 Aberdeen, South Dakota 57401 Table of Contents 1.0 INTRODUCTION AND BACKGROUND ............................................................................... 1-1 1.1 Purpose and Need for Action .................................................................................... 1-1 1.1.1 Purpose ......................................................................................................... 1-1 1.1.2 Need .............................................................................................................. 1-1 1.1.3 NEPA and Project Review ............................................................................ 1-1 2.0 PROPOSED ACTION AND ALTERNATIVES CONSIDERED ............................................ 2-1 2.1 Alternatives Considered ............................................................................................ 2-1 2.1.1 No Action Alternative .................................................................................... 2-1 2.1.2 Proposed Action............................................................................................ 2-1 2.1.3 Alternatives Considered but Eliminated from Further Study ........................ 2-1 2.2 Details of the Proposed Action .................................................................................. 2-1 2.2.1 Construction .................................................................................................. 2-5 2.2.2 Operation ...................................................................................................... 2-6 2.2.3 Decommissioning and Reclamation ............................................................. 2-7 2.3 Measures to Avoid or Reduce Potential Impacts ...................................................... 2-7 3.0 AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES ...................... 3-1 3.1 Introduction ................................................................................................................ 3-1 3.2 Geology ..................................................................................................................... 3-1 3.2.1 Existing Environment .................................................................................... 3-1 3.2.2 Impacts.......................................................................................................... 3-2 3.2.2.1 No Action Alternative ..................................................................... 3-2 3.2.2.2 Proposed Action ............................................................................ 3-2 3.3 Paleontology .............................................................................................................. 3-3 3.3.1 Existing Environment .................................................................................... 3-3 3.3.2 Impacts.......................................................................................................... 3-3 3.3.2.1 No Action Alternative ..................................................................... 3-3 3.3.2.2 Proposed Action ............................................................................ 3-3 3.4 Air Quality .................................................................................................................. 3-4 3.4.1 Existing Environment .................................................................................... 3-4 3.4.1.1 Regional Air Quality ....................................................................... 3-4 3.4.1.2 Regional Climate ........................................................................... 3-4 Table of Contents (cont.) 3.4.2 Impacts.......................................................................................................... 3-5 3.4.2.1 No Action Alternative ..................................................................... 3-5 3.4.2.2 Proposed Action ............................................................................ 3-5 3.5 Climate Change and Greenhouse Gases ................................................................. 3-6 3.5.1 Existing Environment .................................................................................... 3-7 3.5.2 Impacts.......................................................................................................... 3-7 3.5.2.1 No Action Alternative ..................................................................... 3-7 3.5.2.2 Proposed Action ............................................................................ 3-7 3.6 Soils ........................................................................................................................... 3-9 3.6.1 Existing Environment .................................................................................... 3-9 3.6.1.1 Soil Resources .............................................................................. 3-9 3.6.1.2 Soil Taxonomy............................................................................... 3-9 3.6.2 Impacts........................................................................................................ 3-13 3.6.2.1 No Action Alternative ................................................................... 3-13 3.6.2.2 Proposed Action .......................................................................... 3-13 3.7 Vegetation ............................................................................................................... 3-15 3.7.1 Existing Environment .................................................................................. 3-15 3.7.1 Impacts........................................................................................................ 3-16 3.7.1.1 No Action Alternative ................................................................... 3-16 3.7.1.2 Proposed Action .......................................................................... 3-16 3.8 Wetlands .................................................................................................................. 3-19 3.8.1 Existing Environment .................................................................................. 3-19 3.8.1 Impacts........................................................................................................ 3-19 3.8.1.1 No Action Alternative ................................................................... 3-19 3.8.1.1 Proposed Action .......................................................................... 3-19 3.9 Water Resources ..................................................................................................... 3-23 3.9.1 Existing Environment .................................................................................. 3-23 3.9.2 Impacts........................................................................................................ 3-23 3.9.2.1 No Action Alternative ................................................................... 3-24 3.9.2.2 Proposed Action .......................................................................... 3-24 3.10 Threatened, Endangered, and Candidate Species ................................................ 3-24 3.10.1 Existing Environment .................................................................................. 3-25 3.10.1.1 Whooping Crane ......................................................................... 3-25 3.10.1.2 Northern Long-eared Bat ............................................................ 3-26 3.10.1.3 Rufa Red Knot ............................................................................. 3-26 Table of Contents (cont.) 3.10.1.4 Western Prairie Fringed Orchid .................................................. 3-27 3.10.1.5 Black-footed Ferret ...................................................................... 3-27 3.10.1.6 Sprague’s Pipit ............................................................................ 3-28 3.10.2 Impacts........................................................................................................ 3-28 3.10.2.1 No Action Alternative ................................................................... 3-28 3.10.2.2 Proposed Action .......................................................................... 3-28 3.10.2.2.1 Whooping Crane....................................................... 3-28 3.10.2.2.2 Northern Long-eared Bat .......................................... 3-29 3.10.2.2.3 Rufa Red Knot .......................................................... 3-29 3.10.2.2.4 Western Prairie Fringed Orchid ................................ 3-29 3.10.2.2.5 Black-footed Ferret ................................................... 3-29 3.10.2.2.6 Sprague’s Pipit ......................................................... 3-29 3.11 Wildlife ..................................................................................................................... 3-29 3.11.1 Existing Environment .................................................................................. 3-30 3.11.2 Impacts.......................................................................................................