1 11.4 DRY LAKE VALLEY NORTH 2 3 4 11.4.1 Background and Summary of Impacts 5 6 7 11.4.1.1 General Information 8 9 The proposed Dry Lake Valley North SEZ is located in Lincoln County in southeastern 10 Nevada (Figure 11.4.1.1-1). The SEZ has a total area of 76,874 acres (311 km2). In 2008, the 11 county population was 4,643, while adjacent Clark County to the south had a population 12 of 1,879,093. The closest population centers to the SEZ are Pioche, located about 15 mi (24 km) 13 to the east, and Caliente, located about 15 mi (24 km) to the southeast; both communities have 14 populations of about 1,000. The smaller communities of Caselton and Prince are located about 15 13 mi (21 km) to the east of the SEZ. Las Vegas is located about 110 mi (180 km) to the south. 16 17 The nearest major road to the Dry Lake Valley North SEZ is State Route 318, which is 18 about 7 mi (11 km) to the west of the SEZ, while U.S. 93 is about 8 mi (13 km) to the south. 19 Access to the interior of the SEZ is by dirt roads. The nearest railroad access is approximately 20 25 mi (40 km) away, while nearby airports include Lincoln County Airport in Panaca and Alamo 21 Landing Field in Alamo, which are located about 13 mi (21 km) south–southeast of and 35 mi 22 (56 km) southwest of the SEZ, respectively. The proposed Delamar Valley SEZ lies about 23 mi 23 (37 km) to the south of the proposed Dry Lake Valley North SEZ. 24 25 A 69-kV transmission line intersects the southeast corner of the SEZ. It is assumed that 26 this existing transmission line could potentially provide access from the SEZ to the transmission 27 grid (see Section 11.4.1.1.2). 28 29 There are one pending solar development ROW application, six authorized and one 30 pending wind site testing applications, and one pending wind development application on BLM- 31 administered land within a 50-mi (80-km) radius of the proposed Dry Lake Valley North SEZ. 32 There are currently no solar applications within the SEZ. These applications are discussed in 33 Section 11.4.22.2.1. 34 35 The proposed Dry Lake Valley North SEZ is undeveloped and remote. The overall 36 character of the surrounding land is rural. The SEZ is located in the Dry Lake Valley and is 37 framed by mountain ranges on the east and west. The North Pahroc Range rises about 6 mi 38 (10 km) west of the SEZ, and the West Range, Bristol Range, Highland Range, Ely Springs 39 Range, Black Canyon Range, and Burnt Springs Range occur east of the SEZ. No permanent 40 surface water sources occur in the proposed SEZ. Vegetation is generally sparse, with large 41 areas of low grasses and low-height scrubland. 42 43 The proposed Dry Lake Valley North SEZ in Nevada and other relevant information are 44 shown in Figure 11.4.1.1-1. The criteria used to identify the proposed Dry Lake Valley North 45 SEZ in Nevada as an appropriate location for solar energy development included proximity to 46 existing transmission lines or designated corridors, proximity to existing roads, a slope of 47 generally less than 2%, and an area of more than 2,500 acres (10 km2). In addition, the area 48 was identified as being relatively free of other types of conflicts, such as USFWS-designated Draft Solar PEIS 11.4-1 December 2010 1 2 FIGURE 11.4.1.1-1 Proposed Dry Lake Valley North SEZ Draft Solar PEIS 11.4-2 December 2010 1 critical habitat for threatened and endangered species, ACECs, SRMAs, and NLCS lands 2 (see Section 2.2.4.1 for the complete list of exclusions). Although these classes of restricted 3 lands were excluded from the proposed Dry Lake Valley North SEZ, other restrictions might 4 be appropriate. The analyses in the following sections address the affected environment and 5 potential impacts associated with utility-scale solar energy development in the proposed SEZ 6 for important environmental, cultural, and socioeconomic resources. 7 8 As initially announced in the Federal Register on June 30, 2009, the proposed Dry Lake 9 Valley North SEZ encompassed 49,775 acres (201 km2). Subsequent to the study area scoping 10 period, the boundaries of the proposed Dry Lake Valley North SEZ were altered substantially 11 after further observations by the BLM District Office indicating that the additional area met all 12 criteria for solar development. The revised SEZ is approximately 27,100 acres (110 km2), or 13 about 54%, larger than the original SEZ as published in June 2009. 14 15 16 11.4.1.2 Development Assumptions for the Impact Analysis 17 18 Maximum solar development of the proposed Dry Lake Valley North SEZ is assumed to 19 be 80% of the SEZ area over a period of 20 years; these values are shown in Table 11.4.1.2-1, 20 along with other development assumptions. Full development of the Dry Lake Valley North SEZ 21 would allow development of facilities with an estimated total of 6,833 MW of electrical power 22 capacity if power tower, dish engine, or PV technologies were used, assuming 9 acres/MW 23 (0.04 km2/MW) of land required, and an estimated 12,300 MW of power if solar trough 24 technologies were used, assuming 5 acres/MW (0.02 km2/MW) of land required. 25 26 Availability of transmission from SEZs to load centers will be an important consideration 27 for future development in SEZs. The nearest existing transmission line is a 69-kV line that runs 28 through the SEZ. It is possible that this existing line could be used to provide access from the 29 SEZ to the transmission grid, but the 69-kV capacity of that line would be inadequate for 6,833 30 to 12,300 MW of new capacity (note: a 500- kV line can accommodate approximately the load 31 of one 700-MW facility). At full build-out capacity, it is clear that substantial new transmission 32 and/or upgrades of existing transmission lines would be required to bring electricity from the 33 proposed Dry Lake Valley North SEZ to load centers; however, at this time, the location and size 34 of such new transmission facilities are unknown. Generic impacts of transmission and associated 35 infrastructure construction and of line upgrades for various resources are discussed in Chapter 5. 36 Project-specific analyses would need to identify the specific impacts of new transmission 37 construction and line upgrades for any projects proposed within the SEZ. 38 39 For the purposes of analysis in the PEIS, it was assumed that an existing 69-kV 40 transmission line that intersects the SEZ could provide initial access to the transmission grid; 41 thus, no additional acreage disturbance for transmission line access was assessed. Access to the 42 existing 69-kV transmission line was assumed, without additional information on whether this 43 line would be available for connection of future solar facilities. If a connecting transmission line 44 were constructed in the future to connect facilities within the SEZ to a different, off-site, grid 45 location from the one assumed here, site developers would need to determine the impacts from 46 construction and operation of that line. In addition, developers would need to determine the 47 impacts of line upgrades if they are needed. Draft Solar PEIS 11.4-3 December 2010 TABLE 11.4.1.2-1 Proposed Dry Lake Valley North SEZAssumed Development Acreages, Maximum Solar MW Output, Access Roads, and Transmission Line ROWs Distance to Distance Area of Assumed Nearest and Capacity Assumed Distance to Total Acreage and Maximum SEZ State, U.S., of Nearest Transmission Nearest Assumed Output for or Existing Line ROW Designated Developed Acreage Various Solar Interstate Transmission and Road Transmission (80% of Total) Technologies Highway Line ROW Corridore 76,874 acres and 6,833 MWb NV 318 0 mi and 0 acres and 0 mi 61,499 acresa and 7 mid 69 kV 51 acres 12,300 MWc a To convert acres to km2, multiply by 0.004047. b Maximum power output if the SEZ were fully developed using power tower, dish engine, or PV technologies, assuming 9 acres/MW (0.04 km2/MW) of land required. c Maximum power output if the SEZ were fully developed using solar trough technologies, assuming 5 acres/MW (0.02 km2/MW) of land required. d To convert mi to km, multiply by 1.609. e BLM-designated corridors are developed for federal land use planning purposes only and are not applicable to state-owned or privately owned land. 1 2 3 An additional 51 acres (0.2 km2) would be needed for new road access to support solar 4 development in the Dry Lake Valley North SEZ, as summarized in Table 11.4.1.2-1. This 5 estimate was based on the assumption that a new 7-mi (11-km) access road to the nearest major 6 road, State Route 318, would support construction and operation of solar facilities. While there 7 are dirt/ranch roads within the SEZ, additional internal road construction would likely be 8 required to support solar facility construction. 9 10 11 11.4.1.3 Summary of Major Impacts and SEZ-Specific Design Features 12 13 In this section, the impacts and SEZ-specific design features assessed in Sections 11.4.2 14 through 11.4.21 for the proposed Dry Lake Valley North SEZ are summarized in tabular form.