Botany and Wetlands Study Report
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Botany and Wetlands Study Report Swan Lake Expansion Project (FERC Project No. 2911) Revised Final April 2013 Ketchikan, Alaska Prepared by: Kathryn Beck, Botanist Beck Botanical Services, and Karen Brimacombe, Ecologist Tetra Tech Bothell, Washington and McMillen, LLC Boise, Idaho Botany and Wetlands Study Report Southeast Alaska Power Agency TABLE OF CONTENTS 1 Introduction .........................................................................................................1 1.1 Project Description .......................................................................................................... 1 1.2 Purposes of the 2012 Environmental Field Program....................................................... 3 1.3 Changes Made to the Study Plan in Response to Comments or Permit Conditions ....... 3 1.4 Compliance with Permit Terms, Conditions, and Regulatory Framework ...................... 3 1.4.1 Tongass Land and Resource Management Plan............................................ 4 1.4.2 Clean Water Act ............................................................................................ 6 1.4.3 Other Regulations ......................................................................................... 6 2 Procedures ...........................................................................................................6 2.1 Analysis Area ................................................................................................................... 6 2.2 Pre-Field Contact with Forest Service and Review of Existing Information .................... 7 2.3 Field Investigation Surveys .............................................................................................. 7 2.3.1 Sensitive and Rare Plants .............................................................................. 8 2.3.2 Wetland Resources ....................................................................................... 8 3 Environmental Setting ..........................................................................................8 3.1 Vegetation Resources ...................................................................................................... 9 3.2 Sensitive Plants .............................................................................................................. 10 3.3 Rare Plants ..................................................................................................................... 11 3.4 Plant Species Newly Documented in Alaska .................................................................. 13 3.5 General Vegetation Types ............................................................................................. 13 3.6 Invasive Plants ............................................................................................................... 15 3.7 Wetland Resources ........................................................................................................ 15 3.7.1 Forested Wetlands ...................................................................................... 17 3.7.2 Emergent Sedge Wetlands .......................................................................... 17 3.7.3 Moss Muskegs ............................................................................................. 17 4 Project Effects .................................................................................................... 18 4.1 Identified Issues and Concerns for Sensitive Plants ...................................................... 18 4.1.1 Spatulate moonwort (Botrychium spathulatum W.H.Wagner) ................ 19 Swan Lake Hydroelectric Project April 2013 FERC Project No. 2911 Page i Version: Revised Final Botany and Wetlands Study Report Southeast Alaska Power Agency 4.1.2 Edible thistle (Cirsium edule var. macounii (Greene) D.J.Keil) .................... 19 4.1.3 Mountain lady’s slipper (Cypripedium montanum Douglas ex Lindl.) ........ 19 4.1.4 Large Yellow Lady’s Slipper Orchid (Cypripedium parviflorum Salisb. var. pubescens (Willdenow) O. W. Knight) ......................................................... 20 4.1.5 Calder’s lovage (Ligusticum calderi Math. & Const.) .................................. 20 4.1.6 Alaska Rein Orchid (Piperia unalascensis (Spreng.) Rydb.) ......................... 20 4.1.7 Lesser Round‐Leaved Orchid (Platanthera orbiculata (Pursh) Lindl.) ......... 21 4.1.8 Kruckeberg’s swordfern (Polystichum kruckebergii W.H. Wagner) ........... 21 4.2 Identified Issues and Concerns for Rare Plants ............................................................. 22 4.2.1 Maidenhair spleenwort (Asplenium trichomanes L. ssp. trichomanes) ...... 22 4.2.2 Brightgreen spleenwort (Asplenium trichomanes‐ramosum L.) ................. 22 4.2.3 Boreal bedstraw (Galium kamtschaticum Steller ex Schult & Schult) ........ 23 4.2.4 Northern bugleweed (Lycopus uniflorus Michx.) ........................................ 23 4.2.5 Bog adder’s‐mouth orchid (Malaxis paludosa (L.) Swartz) ......................... 24 4.2.6 Choris’ bog‐orchid (Platanthera chorisiana (Cham.) Reichenb.) ................ 25 4.2.7 Pacific Buttercup (Ranunculus pacificus (Hulten) L.D.Benson) ................... 25 4.3 Identified Issues and Concern for Plants Newly Documented in Alaska ....................... 26 4.3.1 Wallace’s spikemoss (Selaginella wallacei Heiron.) .................................... 26 4.3.2 Bog St. John’s‐wort (Hypericum anagalloides Cham. & Schltdl.) ................ 27 4.4 Management Requirements and Mitigation Measures for Sensitive and Rare Plants . 27 4.5 Identified Issues and Concerns for General Vegetation ................................................ 28 4.5.1 Old‐Growth Forest ...................................................................................... 28 4.5.2 Young Growth Forest .................................................................................. 29 4.6 Management Requirements and Mitigation Measures for General Vegetation .......... 29 4.7 Identified Issues and Concerns to Wetland Resources ................................................. 30 4.7.1 Effects from Rising Reservoir Levels Within the Analysis Area ................... 30 4.7.2 Effects from Construction‐related Activities Occuring at and Below the Dam ............................................................................................ 31 4.8 Management Requirements and Mitigation Measures for Wetland Resources .......... 32 5 References ........................................................................................................... 32 Swan Lake Hydroelectric Project April 2013 FERC Project No. 2911 Page ii Version: Revised Final Botany and Wetlands Study Report Southeast Alaska Power Agency TABLES Table 1. Known or Suspected Sensitive Plants in the Ketchikan-Misty Fiords Ranger District .... 10 Table 2. Rare Plants Observed within the Analysis Area .............................................................. 11 Table 3. General Vegetation Types in the Analysis Area1/ ............................................................ 13 Table 4. Acres of Wetland Resources in the Analysis Area1/ ........................................................ 15 FIGURES Figure 1. Project Vicinity ................................................................................................................. 2 Figure 2. Rare Plants Observed within the Survey Study Area ..................................................... 12 Figure 3. Vegetation Communities in the Analysis Area .............................................................. 14 Figure 4. Wetlands in the Survey Study Area ............................................................................... 16 ATTACHMENTS Attachment 1 Response to Agency Comments Received Attachment 2 Forest Service Alaska Region Sensitive Species List, May 2012 Attachment 3 Alaska Natural Heritage Program 2012 Rare Vascular Plant List Attachment 4 Swan Lake Project Area Photos Attachment 5 Botanical Survey Types Attachment 6 Rare Plant Element Occurrence Field Forms Attachment 7 Description of Rare Plant Populations Swan Lake Hydroelectric Project April 2013 FERC Project No. 2911 Page iii Version: Revised Final Botany and Wetlands Study Report Southeast Alaska Power Agency ACRONYMS AND ABBREVIATIONS AKNHP Alaska Natural Heritage Program BMP Best Management Practices CFR Code of Federal Regulations EPA United States Environmental Protection Agency FERC Federal Energy Regulatory Commission ft feet FSH Forest Service Handbook FSM Forest Service Manual GIS geographic information system GPS global positioning system ICD Initial Consultation Document LUD land use designation MMI Mass Movement Index mi miles NEPA National Environmental Policy Act NMFA National Forest Management Act NF National Forest NFS National Forest System NWI National Wetlands Inventory PMF probable maximum flood Project Swan Lake Hydroelectric Project SEAPA Southeast Alaska Power Agency SMU Soil Management Units TES threatened, endangered and sensitive USDA United States Department of Agriculture USFS United States Department of Agriculture, Forest Service Swan Lake Hydroelectric Project April 2013 FERC Project No. 2911 Page iv Version: Revised Final Botany and Wetlands Study Report Southeast Alaska Power Agency 1 INTRODUCTION 1.1 Project Description The Southeast Alaska Power Agency (SEAPA) is the licensee for the Swan Lake Project, Federal Energy Regulatory (FERC) No. 2911 (Project), on the northeast side of Carroll Inlet in Southeast Alaska. SEAPA is currently evaluating