1and, hence, dust production and deposition, with broad implications with regard to

2biogeochemical cycling and impacts on arctic and mountain snowpack depths and

5As the effects of global climate change continue to affect the six-state region, it is

6very likely that, associated with northward migration of storm tracks (USGCRP

72009), desertification will intensify; thus, it will be more likely that more dust will

8be produced as vegetative cover decreases and as soils dry (Morman 2010).

9USGS scientists have been studying the sources and compositions of dust across

10the southwest deserts, from both natural and anthropogenic sources, including the

11dust in terminal lake valleys in southern California and Nevada in which solar

12developments are being contemplated in this PEIS (Reheis et al. 2009). The

13studies are finding that dust from terminal lake basins could be transported

14hundreds of miles and could be a global source of metal-bearing and potentially

15toxic dust. Not only are the dusts readily available, but they are also easily

16respired and highly bioaccessible (Morman 2010; Reheis et al. 2003). While there

17is some variability among dust sources, all include a mixture of arsenic, cadmium,

18chromium, copper, lead, nickel, and zinc, all of which are potentially toxic to

19humans (Morman 2010; Reheis et al. 2003, 2009).

20

21It is widely understood that impurities in snow, such as dust or soot, decrease

22snow albedo and enhance solar radiation absorption and melt rates. Dust may

23shorten snow cover duration by as much as a month (Painter et al. 2007). Earlier

24spring snowmelt has broad implications with regard to water resources in

25southwestern states that are already strapped for water, especially during the

26summer when peak demand is higher, and it leads to an increased number of

27forest fires (USGCRP 2009). The problem of disturbed desert dust causing

28regional climate change and early snowmelt is discussed in numerous recent

29scientific articles. Neff et al. (2008) documented how the phenomenon of dust

30causing snowmelt was largely coincidental with increased settlement of the

31American West. The deposition of this disturbed desert dust on snow leads to

32early snow melt (Painter et al. 2007). In the Colorado River Basin, these effects

33are significant. Painter et al. (2010) estimated that the landing of disturbed desert

34soils traceable to settlement of the American West on mountain snowpack in the

35Upper Colorado River Basin has resulted in a net loss of approximately 5% of the

36annual flow of the Colorado River as measured at Lees Ferry, Arizona. It is likely

37that most of this dust on mountain snowpack is coming from nearby lands where

38soil-disturbing activity has made the land susceptible to wind erosion. Activities

39such as energy development, off-road vehicle use, and grazing serve to destabilize

40soils, making them more susceptible to wind erosion (Belnap et al. 2009).

41

42

43 4.12 VISUAL RESOURCES

44

45Section 4.12 of the Draft Solar PEIS described BLM’s responsibilities for managing

46scenic resources on public lands, briefly described BLM’s VRM program, and provided a more

1detailed description of BLM’s visual resource inventory process. The section included a

12TABLE 4.12-1 Summary of Selected Potentially Sensitive Visual Resource Areas within the

13Six-State Study Areaa

aIncludes features wholly or partly within state boundaries.

bDoes not include national historical parks.

cIncludes national monuments managed by the NPS, USFS, BLM, and USFWS.

dIncludes National Recreation Areas managed by the NPS and USFS.

eIncludes Headwaters Forest Reserve.

fIncludes National Historical Parks, National Preserves, National Reserves, National Seashores, National Historic Sites, National Battlefields, National Memorials, National Memorial Parkways, and the San Francisco Presidio.

gIncludes All-American Roads and National Scenic Byways.

hThe congressionally authorized wild and scenic study rivers are not included. See Section 4.9.1.2 for details on this classification.

14

1 4.13 ACOUSTIC ENVIRONMENT

2

3 The information provided in Section 4.13 of the Draft Solar PEIS remains valid, with the 4 following update to Section 4.13.1 (Noise):

5

6• Authorized military training flights (MTRs) pass directly over or proximal to

15As discussed in Section 4.14 of the Draft Solar PEIS, paleontological resources are

16fossilized remains, imprints, and traces of plants and animals preserved in rocks and sediments.

17There is a potential for paleontological resources (either individual specimens or larger

18assemblages of multiple fossils) to be present in sedimentary formations within the areas

19potentially suitable for solar development. Various statutes, regulations, and policies govern the

20management of paleontological resources on public lands. In short, these policies protect

21paleontological resources for scientific, educational, and preservation purposes and provide civil

22and criminal penalties for theft and vandalism of these resources. The goal of the BLM program

23is to locate, evaluate, manage, and protect paleontological resources on public lands.

24

25The Potential Fossil Yield Classification (PFYC) system is used to classify geologic units

26at the formation or member level according to their probability of yielding paleontological

27resources of concern to land managers. Under the PFYC system, geologic units are classified

28from Class 1 to Class 5 on the basis of the relative abundance of vertebrate fossils or uncommon

29invertebrate or plant fossils and their sensitivity to adverse impacts. A higher classification

30number indicates a higher fossil yield potential and greater sensitivity to adverse impacts. BLM

31paleontologists have completed PFYC mapping in Colorado, Utah, and New Mexico and will

32continue to refine those maps as more information is collected. There are no completed PFYC

33maps of Arizona, California, and Nevada at this time. Site-specific information regarding

34paleontological resources would need to be collected to define the affected environment for an

35individual project.

36

37The data provided in Section 4.14 remain valid, except for Table 4.14-1, which has been

38updated as a result of the revisions to lands available for application through the variance

39process, and based on updates to the Taos Field Office RMP (changes are in bold).

40

41

42 4.15 CULTURAL RESOURCES

43

44As discussed in Section 4.15 of the Draft Solar PEIS, cultural resources include

45archaeological sites, historic structures and features, and traditional cultural properties that are

46addressed under the National Historic Preservation Act (NHPA), as amended (P.L. 89-665).