B L M U.S. Department of the Interior Bureau of Land Management Environmental Assessment DOI-BLM-NV-S010-2012-0146-EA September 2012 Techren Boulder City Solar Project 69kV Gen-Tie Transmission Line Project NVN-90395 PREPARING OFFICE U.S. Department of the Interior Bureau of Land Management Southern Nevada District Office Las Vegas Field Office 4701 N Torrey Pines Drive Las Vegas, Nevada 702–515–5172 Office 702–515–5010 Fax Environmental Assessment DOI-BLM-NV-S010-2012-0146-EA This page intentionally left blank DOI-BLM-NV-S010-2012-0146-EA iii Table of Contents Glossary ........................................................................................................................................... 1 1. Introduction ................................................................................................................................ 3 1.1. Identifying Information: ................................................................................................... 5 1.1.1. Title, EA number, and type of project: .................................................................. 5 1.1.2. Location of Proposed Action: ................................................................................ 5 1.1.3. Name and Location of Preparing Office: ............................................................... 5 1.1.4. Identify the subject function code, lease, serial, or case file number: ................... 5 1.1.5. Applicant Name: .................................................................................................... 5 1.2. Purpose and Need ............................................................................................................. 5 1.2.1. Background ............................................................................................................ 6 1.2.2. Purpose and Need for the Action ........................................................................... 6 1.2.3. Scope of Analysis and Decisions to be Made ........................................................ 6 1.2.4. Relationship to Laws, Regulations, Policies, and Other Plans .............................. 9 1.2.5. Supplemental Authorities ....................................................................................... 9 1.3. Scoping, Public Involvement and Issues: ....................................................................... 10 2. Proposed Action and Alternatives .......................................................................................... 13 2.1. Description of the Proposed Action: .............................................................................. 15 2.1.1. Non-federal Connected Action ............................................................................ 15 2.2. Overview of Alternative 1 and Alternative 2 .................................................................. 15 2.2.1. Alternative 1 ......................................................................................................... 17 2.2.2. Alternative 2 ......................................................................................................... 18 2.2.3. No Action Alternative .......................................................................................... 18 2.2.4. Alternatives Considered but not Analyzed in Detail ........................................... 18 2.3. Proposed Project Facilities .............................................................................................. 18 2.3.1. Site Preparation and Mobilization Activities ....................................................... 19 2.3.2. Waste and Hazardous Materials Management ..................................................... 20 2.3.3. Surface Reclamation ............................................................................................ 20 2.3.4. Best Management Practices ................................................................................. 21 2.4. Project Construction Schedule ........................................................................................ 21 2.5. Conformance ................................................................................................................... 22 3. Affected Environment, Environmental Consequences, and Mitigation Measures ............ 23 3.1. Proposed Project General Setting ................................................................................... 25 3.2. Air Quality and Climate .................................................................................................. 25 3.2.1. Affected Environment .......................................................................................... 25 3.2.2. Environmental Consequences .............................................................................. 27 3.2.2.1. No Action Alternative ............................................................................... 27 3.2.2.2. Alternative 1 .............................................................................................. 27 3.2.2.3. Alternative 2 .............................................................................................. 28 3.2.2.4. Connected Action ...................................................................................... 28 Table of Contents iv DOI-BLM-NV-S010-2012-0146-EA 3.2.3. Mitigation ............................................................................................................. 31 3.3. Geology, Minerals, and Soils .......................................................................................... 31 3.3.1. Affected Environment .......................................................................................... 31 3.3.2. Environmental Consequences .............................................................................. 32 3.3.2.1. No Action Alternative ............................................................................... 32 3.3.2.2. Alternative 1 .............................................................................................. 32 3.3.2.3. Alternative 2 .............................................................................................. 32 3.3.2.4. Connected Action ...................................................................................... 33 3.3.3. Mitigation ............................................................................................................. 33 3.4. Water Resources .............................................................................................................. 33 3.4.1. Affected Environment .......................................................................................... 33 3.4.1.1. Groundwater ............................................................................................. 33 3.4.1.2. Surface Water ............................................................................................ 34 3.4.2. Environmental Consequences .............................................................................. 34 3.4.2.1. No Action Alternative ............................................................................... 34 3.4.2.2. Alternative 1 .............................................................................................. 34 3.4.2.3. Alternative 2 .............................................................................................. 35 3.4.2.4. Connected Action ...................................................................................... 35 3.4.3. Mitigation ............................................................................................................. 35 3.4.3.1. Groundwater ............................................................................................. 35 3.4.3.2. Surface Water ............................................................................................ 36 3.5. Vegetation ....................................................................................................................... 36 3.5.1. Affected Environment .......................................................................................... 36 3.5.2. Environmental Consequences .............................................................................. 36 3.5.2.1. No Action Alternative ............................................................................... 36 3.5.2.2. Alternative 1 .............................................................................................. 36 3.5.2.3. Alternative 2 .............................................................................................. 37 3.5.2.4. Connected Action ...................................................................................... 37 3.5.3. Mitigation ............................................................................................................. 37 3.6. Special Status Vegetation ................................................................................................ 37 3.6.1. Existing Condition ............................................................................................... 37 3.6.2. Environmental Consequences .............................................................................. 38 3.6.2.1. No Action Alternative ............................................................................... 38 3.6.2.2. Alternative 1 .............................................................................................. 38 3.6.2.3. Alternative 2 .............................................................................................. 38 3.6.2.4.