National Park Service Rehabilitate Failing Park Sewage System U.S. Department of the Interior Bryce Canyon National Park Environmental Assessment Bryce Canyon, Utah October 2010 This page intentionally left blank. Table of Contents SUMMARY ................................................................................................................................................ V PURPOSE AND NEED ..............................................................................................................................1 Introduction ............................................................................................................................................1 Background ............................................................................................................................................3 Purpose and Need...................................................................................................................................3 Relationship to Other Plans and Policies................................................................................................3 Appropriate Use .....................................................................................................................................4 Scoping...................................................................................................................................................5 Impact Topics Retained for Further Analysis.........................................................................................5 Threatened, Endangered, Rare, and Protected Species (Utah Prairie Dog Only) ............................6 Wildlife ............................................................................................................................................6 Vegetation........................................................................................................................................6 Visitor Use and Experience .............................................................................................................6 Impact Topics Dismissed From Further Analysis ..................................................................................7 Threatened, Endangered, Rare, and Protected Species (UPD Excluded) ........................................7 State Listed or Other Sensitive Species ...........................................................................................8 Topography, Geology, and Soils .....................................................................................................9 Paleontological Resources ...............................................................................................................9 Archeological Resources ...............................................................................................................10 Ethnographic Resources.................................................................................................................10 Cultural Landscapes.......................................................................................................................11 Historic Structures and Districts ....................................................................................................11 Museum Collections ......................................................................................................................12 Water Resources ............................................................................................................................12 Wetlands ........................................................................................................................................13 Floodplains.....................................................................................................................................14 Air Quality .....................................................................................................................................14 Natural Soundscapes......................................................................................................................15 Lightscapes ....................................................................................................................................15 Socioeconomics .............................................................................................................................15 Prime and Unique Farmlands.........................................................................................................15 Indian Trust Resources ..................................................................................................................16 Environmental Justice....................................................................................................................16 Climate Change..............................................................................................................................16 Park Operations..............................................................................................................................16 ALTERNATIVES CONSIDERED .........................................................................................................17 Alternatives Carried Forward...............................................................................................................17 Alternative A – No-Action.............................................................................................................17 Alternative B – Open-Cut Trench Method ....................................................................................17 Alternative C – Pipe Bursting Methodology through Utah Prairie Dog Occupied Areas (Preferred Alternative)...................................................................................................................18 Mitigation Measures.............................................................................................................................20 i Alternatives Considered and Dismissed...............................................................................................25 Alternative Summaries .........................................................................................................................25 Identification of the Environmentally Preferred Alternative................................................................29 AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES ..............................30 Cumulative Effects ...............................................................................................................................30 Threatened, Endangered, Rare, and Protected Species (UPD Only)....................................................32 Intensity Level Definitions ............................................................................................................34 Impacts of Alternative A (No-Action Alternative) ........................................................................34 Impacts of Alternative B (Open-Cut Trench Method)...................................................................35 Impacts of Alternative C (Preferred Alternative) ..........................................................................36 Wildlife.................................................................................................................................................37 Affected Environment....................................................................................................................37 Intensity Level Definitions ............................................................................................................38 Impacts of Alternative A (No-Action Alternative) ........................................................................38 Impacts of Alternative B (Open-Cut Trench Method)...................................................................39 Impacts of Alternative C (Preferred Alternative) ..........................................................................39 Vegetation ............................................................................................................................................40 Affected Environment....................................................................................................................40 Intensity Level Definitions ............................................................................................................41 Impacts of Alternative A (No-Action Alternative) ........................................................................41 Impacts of Alternative B (Open-Cut Trench Method)...................................................................42 Impacts of Alternative C (Preferred Alternative) ..........................................................................43 Visitor Use and Experience..................................................................................................................43 Intensity Level Definitions ............................................................................................................44 Impacts of Alternative A (No-Action Alternative) ........................................................................44 Impacts of Alternative B (Open-Cut Trench Method)...................................................................45 Impacts of Alternative C (Preferred Alternative) ..........................................................................46 CONSULTATION