Bynum Hydroelectric Project FERC Project Nos
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ENVIRONMENTAL ASSESSMENT FOR HYDROPOWER LICENSE Bynum Hydroelectric Project FERC Project Nos. 14858-001, 4093-035 North Carolina Federal Energy Regulatory Commission Office of Energy Projects Division of Hydropower Licensing 888 First Street, NE Washington, D.C. 20426 TABLE OF CONTENTS TABLE OF CONTENTS ..................................................................................................... i LIST OF FIGURES ............................................................................................................ iii LIST OF TABLES.............................................................................................................. iv ACRONYMS AND ABBREVIATIONS............................................................................ v ENVIRONMENTAL ASSESSMENT ................................................................................ 1 1.0 INTRODUCTION ................................................................................................ 1 1.1 APPLICATION .................................................................................................... 1 1.2 PURPOSE OF ACTION AND NEED FOR POWER ......................................... 1 1.2.1 Purpose of Action ............................................................................................ 1 1.2.2 Need for Power ................................................................................................ 2 1.3 STATUTORY AND REGULATORY REQUIREMENTS ................................ 5 1.3.1 Federal Power Act ........................................................................................... 5 1.3.2 Clean Water Act .............................................................................................. 5 1.3.3 Endangered Species Act .................................................................................. 6 1.3.4 Coastal Zone Management Act ....................................................................... 6 1.3.5 National Historic Preservation Act .................................................................. 7 1.4 PUBLIC REVIEW AND COMMENT ................................................................ 7 1.4.1 Scoping ............................................................................................................ 7 1.4.2 Interventions .................................................................................................... 7 1.4.3 Comments on the License Application ........................................................... 8 2.0 PROPOSED ACTION AND ALTERNATIVES ................................................. 8 2.1 NO-ACTION ALTERNATIVE ........................................................................... 8 2.1.1 Existing Project Facilities ................................................................................ 9 2.1.2 Project History ................................................................................................. 9 2.2 APPLICANT’S PROPOSAL ............................................................................. 10 2.2.1 Project Description ........................................................................................ 10 2.2.2 Proposed Project Operation ........................................................................... 10 2.2.3 Project Safety ................................................................................................. 11 2.2.4 Proposed Environmental Measures ............................................................... 11 2.3 STAFF ALTERNATIVE ................................................................................... 12 3.0 ENVIRONMENTAL ANALYSIS ..................................................................... 13 3.1 General Description of the Area ......................................................................... 13 3.2 Scope of Cumulative Effects Analysis ............................................................... 14 3.3 Proposed Action and Action Alternatives .......................................................... 14 3.3.1 Geology and Soils .......................................................................................... 15 3.3.2 Aquatic Resources ......................................................................................... 19 3.3.3 Terrestrial Resources ..................................................................................... 37 3.3.4 Endangered Species ....................................................................................... 43 3.3.5 Recreation, Land Use, and Aesthetics ........................................................... 46 3.3.6 Cultural Resources ......................................................................................... 54 3.4 No-Action Alternative ........................................................................................ 56 i 4.0 DEVELOPMENTAL ANALYSIS .................................................................... 57 4.1 POWER AND ECONOMIC BENEFITS OF THE PROJECT ......................... 57 4.2 COMPARISON OF ALTERNATIVES ............................................................. 58 4.2.1 No-Action Alternative ................................................................................... 59 4.2.2 McMahan Hydro’s Proposal.......................................................................... 59 4.2.3 Staff Alternative ............................................................................................ 59 4.3 COST OF ENVIRONMENTAL MEASURES .................................................. 60 5.0 CONCLUSIONS AND RECOMMENDATIONS ............................................. 67 5.1 COMPREHENSIVE DEVELOPMENT AND RECOMMENDED ALTERNATIVE ................................................................................................ 67 5.1.1 Measures Proposed by McMahan Hydro ...................................................... 67 5.1.2 Additional Measures Recommended by Staff ............................................... 68 5.1.3 Measures Not Recommended by Staff .......................................................... 71 5.2 UNAVOIDABLE ADVERSE EFFECTS .......................................................... 73 5.3 FISH AND WILDLIFE AGENCY RECOMMENDATIONS .......................... 74 5.4 CONSISTENCY WITH COMPREHENSIVE PLANS ..................................... 77 6.0 FINDING OF NO SIGNIFICANT IMPACT .................................................... 77 7.0 LITERATURE CITED ....................................................................................... 78 8.0 LIST OF PREPARERS ...................................................................................... 83 ii LIST OF FIGURES Figure 1. Location of the Bynum Project. .......................................................................... 3 Figure 2. Bynum Project. .................................................................................................... 4 Figure 3. Annual flow duration curve for the Haw River at Bynum................................ 20 Figure 4. Plot of DO and water temperatures in the Haw River from 1997 through 2016. ............................................................................................................................ 31 Figure 5. Project vicinity recreation facilities. ................................................................. 48 Figure 6. Proposed hiking trail. ........................................................................................ 49 iii LIST OF TABLES Table 1. Mean monthly and annual flows in cfs on the Haw River just downstream from the Bynum Hydroelectric Project. ...................................................................... 19 Table 2. North Carolina water quality standards relevant to the Bynum Project. ............ 21 Table 3. Fish Assemblage of the Mainstem Haw River. .................................................. 22 Table 4. Special status aquatic species in the Haw River. ............................................... 23 Table 5. The percentage of days (top) and number of days (bottom) that mean daily flows exceeded the minimum inflow required for the Bynum Project to operate and provide the proposed minimum flow of 120 cfs or 240 cfs (March and April) to the bypassed reach. ............................................................................. 27 Table 6. Bynum Project dimensions used to calculate approach velocity. ...................... 33 Table 7. Swim speeds of nine representative species found in the Bynum impoundment. ............................................................................................................................ 34 Table 8. Target fish species in the Haw River typically used for entrainment analysis. 35 Table 9. Special status terrestrial species. ........................................................................ 40 Table 10. Parameters for the economic analysis for Bynum Project. .............................. 58 Table 11. Summary of the annual cost of alternative power and annual project costs for alternatives for the Bynum Project. ................................................................... 59 Table 12. Cost of environmental mitigation and enhancement measures considered in assessing the environmental effects of the proposed Bynum Project. ............... 61 Table 13. North Carolina WRC section 10(j) recommendations for the Bynum Project. 75 iv ACRONYMS AND ABBREVIATIONS APE area of potential effects AMSL above mean sea level certification water quality certification °C degrees Celsius cfs cubic feet per