Source: U.S. Bureau of the Census (2012).

3

4

5 6.5.2 Cumulative Impact Assessment for Solar Energy Development

6

7Cumulative impacts on important resources that would result from the construction,

8operation, and decommissioning of solar energy development projects, when added to other past,

9present, and reasonably foreseeable future actions described in the previous section are discussed

10below. Although the locations and sizes of specific facilities are not known, on the basis of the

11RFDS developed for this PEIS (see Section 2.4 of this Final Solar PEIS), it is assumed that

12overall solar development in the six-state study area would be approximately 24,000 MW on

13BLM-administered lands, with an additional 8,000 MW on non-BLM lands. This level of

14development would require a corresponding dedicated use of about 214,000 acres (866 km2) of

15BLM-administered lands and 71,000 acres (287 km2) of non-BLM lands. As discussed in the

16introduction to the cumulative impacts section (Section 6.5), the RFDS is considered generally

17applicable to solar development occurring under any of the alternatives evaluated in this PEIS.

18Because of the uncertain nature of future projects in terms of size, number, location, and the

19types of technology that would be employed, the impacts are discussed qualitatively or

20semiquantitatively, with ranges given as appropriate. Detailed cumulative impact analyses are

21provided for individual SEZs in Chapters 8 through 13. More detailed analyses of cumulative

22impacts would be performed in the environmental reviews for specific projects in relation to all

23other existing and proposed projects in the relevant geographic area.

24

1Cumulative impacts on affected resources from the construction, operation, and

2 decommissioning of solar energy development projects, when added to other past, present, and 3 reasonably foreseeable future actions would likely be the same as or less than those analyzed in 4 the Draft Solar PEIS. Since the Draft Solar PEIS was issued, the expected impact from solar

5 energy development on some public lands has been reduced due to the elimination of seven 6 proposed SEZs and the reduction is size of several more. In addition, there are fewer pending

7 solar ROW applications for public lands, falling from 129 pending applications as presented in

8the Draft Solar PEIS to 89 currently listed pending applications (some of these have been

9 denied). Nonetheless, the BLM remains committed to facilitating solar energy development on

10public lands, which it proposes to do through the prioritized processing of ROW applications for

11lands within the proposed SEZ and through the identification of additional SEZs. Overall, the

12RFDS presented in Section 2.4 is still considered applicable to solar development occurring

13under any of the alternatives evaluated in this PEIS, and for use in assessing potential cumulative

14impacts of development.

15

16In general, the cumulative impacts on resources discussed in Sections 6.5.2.1 through

176.5.2.18 of the Draft Solar PEIS remain valid for this Final Solar PEIS. There has been a major

18shift in technology preference, with many projects proposing to convert from CSP to PV, which

19would result in reduced impacts on water resources. This shift would lower the potential for

20cumulative water use impacts presented in Section 6.5.2.8 of the Draft Solar PEIS. Other specific

21updates for Section 6.5.2 of the Draft Solar PEIS are listed below:

22

23

24 6.5.2.1 Lands and Realty

25

26Solar energy facilities, for the most part, would be built in rural areas within the

27six Western states covered by this PEIS in large tracks of flat, open, lands where high levels of

28solar insolation are present. Such lands are typically sparsely populated, often isolated, and

29typically lightly used, including for grazing, mineral production, limited recreation, and ROWs

30for wind energy development, transmission lines, other linear utilities, and roads. Placing solar

31energy facilities in these areas usually represents a new and different land use, creating areas of

32commercial/industrial character in rural environments. Utility-scale facilities would block out

33large tracks of land, cumulatively totaling approximately 285,000 acres (1,153 km2) over the

34next 20 years, removing or limiting many current land uses. Primary effects would be on access

35for grazing and mining and road access for recreation or transport. Existing ROWs representing

36prior rights would be honored, however, and BLM land use plans would be revised to

37accommodate solar development.

38

39Contributions of solar energy development to cumulative impacts on lands and realty

40would be in addition to those from other ROWs for transmission lines, roads, and other facilities

41on public lands and from other energy development on public and private lands that would

42further affect and limit other land uses within a given region. The intensive coverage of land

43surface required by solar facilities renders the land used incompatible for most other uses,

44including grazing, mineral development, and recreation. Although wind and geothermal facilities

45also encompass large areas, they are generally more compatible with such other uses, because

46they require less land and can accommodate multiple uses.

4introduce an industrial land use in typically an otherwise rural area. On a regional and statewide

5basis, while facilities would affect areas of similar topography, thus increasing their relative

6 impacts on such land types, the percentage of such land types affected would remain quite small 7 for the amount of land required to meet the RFDS.

8

9Renewable energy development is by far the largest potential new future use of rural

10lands. No other major contributors to cumulative impacts on lands and realty are foreseeable,

11beyond perhaps additional energy transmission and other linear systems, some of which would

12be built to serve renewable energy development. Thus, renewable energy development would be

13the major contributor to cumulative impacts on land use in the affected regions. Solar energy

14development, because of its intensive land use, would be a major contributor to those impacts.

16While the solar RFDS estimate has not changed since the Draft Solar PEIS was issued,

17seven proposed SEZs have been eliminated and several others reduced in size to address a

18variety of resource concerns. Contributions of solar development to cumulative impacts on land

19use might thus be somewhat less than those characterized in the Draft Solar PEIS as a result of

20reduced dispersion of solar projects in the regions affected by these changes. That is, solar

21projects more closely consolidated would tend to have lower overall impacts on land use factors

22such as access to recreation, changing the character of an area, or interfering with grazing than

23would the same projects more widely dispersed. However, the closely consolidated projects

24would likely have greater impacts on the water resources in the area.

25

26

27 6.5.2.2 Specially Designated Areas and Lands with Wilderness Characteristics

28

29Lands suitable for solar energy development in the six-state area, whether public or

30private, are typically basin flats surrounded by mountains. As such, these lands are often located

31near one or more specially designated areas and lands with wilderness characteristics, which

32often lie in the surrounding mountains but also include protected desert areas. Potential effects of

33nearby solar facilities on these sensitive areas include visual impacts, noise impacts, reduced

34access, impacts on wildlife that use the developed areas, and fugitive dust during construction,

35which may affect visibility.

36

37Cumulative impacts on these sensitive areas would be from increased development and

38visual clutter in general in the surrounding areas, reduced local and regional visibility due to

39construction-related air particulates, light pollution, road traffic, and impacts on wildlife and

40plants. As for land use noted above, renewable energy development is the major foreseeable

41contributor to cumulative impacts on these resources, with solar energy the primary contributor

42in many areas. Other future developments that could affect these areas include mining, OHV use,

43military and civilian aviation, and new transmission lines and other linear facilities. Most such

44developments would affect the viewshed and would produce fugitive dust emissions during

45construction, while mining and aviation would also have noise and vibration effects. While all

46solar technologies would produce visual effects, other impacts would depend on the employed

1 solar technology; generally, PV would have the lowest overall impacts. Solar trough and power 2 tower technologies including a power block would have the greatest impacts, while noise from 3 dish engine facilities might affect some nearby areas. Cumulative effects would be dominated by 4 solar facilities in favorable areas and by renewable energy development in general. Because of 5 the general vastness of the affected area, foreseeable impacts on specially designated areas in the

6 six-state region under the RFDS, assuming a total of approximately 285,000 acres (1,153 km2) of 7 land disturbance, would be relatively small overall, but moderate to large in localized areas for

8 individual specially designated areas, especially with respect to visual impacts. Several design 9 features required under the BLM action alternatives would minimize the impacts from solar

10development, including (1) siting solar facilities as far as possible from key observation points

11(KOPs) and (2) limiting fugitive dust generation during construction through best management

12practices and proper timing of work.

13

14Elimination of and modifications to proposed SEZs would tend to reduce overall

15contributions to cumulative impacts on specially designated areas and lands with wilderness

16characteristics under the RFDS due to consolidation of solar facilities. While effects would

17increase in areas where projects are consolidated, eliminating the presence of facilities altogether

18in other potentially sensitive areas may, at a regional scale, result in impacts of lesser severity or

19magnitude overall.

20

21

22 6.5.2.3 Rangeland Resources

23

24Solar facilities will be located in areas that are currently grazed, while some may also

25affect areas managed for wild horses and burros. However, the number of affected grazing

26allotments is generally small, and in many cases, the allotments would incur only a small

27reduction in size. Indirect impacts could result from disruption of livestock movement or access

28to water sources. A small number of permit holders could be significantly affected, although

29permit holders could be compensated for losses. Solar energy facilities would be a major

30contributor to foreseeable impacts on grazing, since wind and geothermal energy facilities and

31other foreseeable development are generally more compatible with grazing. Cumulative impacts

32on grazing would, however, be small.

33

34Similarly, wild horse and burro management areas could be affected by solar facilities if

35management areas are located within the area of indirect effects, nominally within 5 mi (8 km) of

36the facilities. Solar facilities would generally not be sited directly within HMAs. Design features

37required under the BLM action alternatives would also require protective measures for wild

38horses and burros as needed, such as the provision of movement corridors, traffic management,

39and fencing. Cumulative impacts on wild horse and burro management areas would be small

40overall, as would any contributions from solar facilities. Wild horse and burro management areas

41encompass a small fraction of total available lands, and they also include lands not suitable for

42solar development because of topography and other factors, thus reducing conflicts.

43

44Contributions to cumulative effects on grazing and on wild horse and burro management

45would be reduced overall from the elimination and modification of proposed SEZs since the

46issuance of the Draft Solar PEIS, due to the general consolidation of solar facilities.