I.4.0 BIOLOGICAL AND ECOLOGICAL RESOURCES
This section describes the ecological resources potentially impacted by the proposed action and alternatives. A brief description of the regional environment is followed by a discussion of the ecological resources of the Central Plateau and nearby areas, which are the location of all facilities under all alternatives addressed in this EIS. The material presented is based largely on reports by Cushing (Cushing 1994 and 1995), which summarize many other site studies, on the 1994 biological survey of the TWRS site in the 200 East Area (PNL 1994e), and on the Site Evaluation Report for Candidate Basalt Quarry Sites (Duranceau 1995).
The Hanford Site and adjacent region have been characterized as shrub-steppe (Daubenmire 1970). Shrub-steppe vegetation zones are dominated by a shrub overstory with an understory of grasses. The Hanford Site has not been farmed or grazed by livestock for more than 50 years, allowing it to serve as a refuge for a variety of plant and animal species (Gray-Rickard 1989). Approximately 665 km2 (257 mi2) of undeveloped land within the Hanford Site have been designated as ecological study areas or refuges. Washington State considers shrub-steppe a priority habitat because of its importance to wildlife species of concern. The National Biological Service has identified native shrub and grassland steppe in Washington State and Oregon as an endangered ecosystem.
I.4.1 BIODIVERSITY
Biodiversity has been defined as the diversity of ecosystems, species, and genes, and the variety and variability of life (CEQ 1993). Major components of biodiversity are plant and animal species, microorganisms, ecosystems, and ecological processes, and the interrelationships between and among these components. Biodiversity also is a qualitative measure of the richness and abundance of ecosystems and species in a given area (NPS 1994). Biodiversity also provides a moderating effect on wide fluctuations in environmental conditions.
Two major factors that contribute to biodiversity on the Hanford Site are 1) the Site is one of the largest relatively undisturbed tracts of native shrub-steppe left in Washington State; and 2) the Hanford Reach is the last free-flowing nontidal stretch of the Columbia River in the United States (Sackschewsky et al. 1992 and Cushing 1994). Other factors include topographic features such as Rattlesnake Mountain, Gable Butte, and Gable Mountain, a variety of soil textures ranging from sand to silty and sandy loam, and the lack of human use and development over much of the Hanford Site. Specialized terrestrial habitats contributing to the biodiversity of the Hanford Site include areas of shrub-steppe, basalt outcrops, scarps (cliffs), scree slopes (accumulations of material at the base of a hole or cliff), and sand dunes. Aquatic components of biodiversity are mainly associated with the Columbia River and include aquatic habitat, wetland and riparian areas, and riverain habitat along the Hanford Reach shoreline and islands in the Columbia River.
The biological diversity of the Hanford Site has been emphasized by the recent discovery of 21 new species (two plant and 19 insects) in a study by the Nature Conservancy of Washington (Nature Conservancy 1996) . These species may be dependent on the shrub-steppe environment and destruction, fragmentation, or other disturbance of this habitat could lead to the loss of these and other as yet unidentified species. None of these newly recorded species were found in potential TWRS areas (Brandt 1996).
Ecologically important plant and animal species on the Hanford Site include species of concern (Section I.4.6); commercial and recreational wildlife species such as salmon and steelhead, mule deer, and upland game birds; and plant species used as a source of food, medicine, fiber, and dye in the traditional lifestyles of Native People of the Columbia Basin (Section I.4.7) (Sackschewsky et al. 1992).
As stated previously, the Hanford Site has not been farmed or grazed for over 50 years and thus has served as a refuge for various plant and animal species. However, the invasion and spread of nonnative plant species into previously disturbed areas, such as abandoned farmland, represent a potential threat to biodiversity by displacing native species, simplifying plant communities, and fragmenting habitat. Introduced plant species account for approximately 21 percent of the vascular plants found on the Hanford Site and include species such as cheatgrass, Russian-thistle, and most of the tree species found onsite (Sackschewsky et al. 1992). Most of the Site's disturbed areas include abandoned farmland and areas burned by wildfire. These areas are dominated by pure stands of cheatgrass where the native shrub component has been modified severely or replaced altogether (Cushing 1994).
I.4.2 VEGETATION
The Hanford Site is a relatively undisturbed area of shrub-steppe, which is considered priority habitat by Washington State (WSDW 1993). Also, the National Biological Service has listed native shrub and grassland steppe in Washington and Oregon as an endangered ecosystem. Historically, the predominant plant in the area was big sagebrush (Artemisia tridentata) with an understory of perennial bunch grasses such as Sandbergs bluegrass (Poa sandbergii) and bluebunch wheatgrass (Agropyron spicatum). Following human settlement in the early 1800's, grazing and agriculture disrupted the native vegetation and opened the way for invader species such as tumbleweed or Russian-thistle (Salosa kali) and cheatgrass (Bromus tectorum). Establishing the Hanford Site as a nuclear facility in 1943 created a protected area of mostly undeveloped land with scattered, small industrial complexes. Consequently, the Hanford Site is one of a small number of remaining shrub-steppe tracts in Washington State that is relatively undisturbed.
The Central Plateau and the nearby areas of the potential McGee Ranch and Vernita Quarry borrow sites have been identified as predominantly shrub-steppe (Cushing 1994 and Duranceau 1995). This designation includes communities dominated by big sagebrush and bitterbrush (Purshia tridentata) with an understory of cheatgrass or Sandbergs bluegrass (Figure I.4.2.1). Over 100 plant species occur on the Central Plateau and vicinity. Common plant species include big sagebrush, rabbitbrush (Chrysothamnus nauseous), cheatgrass, and Sandbergs bluegrass(Table I.4.2.1). Much of the 200 Areas (e.g., the tank farms, the sites of several large processing facilities), have been disturbed by human activities. In these disturbed areas, introduced species, such as Russian-thistle and cheatgrass are common (Cushing 1994).
The TWRS sites in the 200 East Area and the immediate surrounding area are approximately 40 percent big sagebrush and rabbitbrush. Another 20 percent is dominated by Russian-thistle, with the remainder disturbed vegetation or bare gravel (PNL 1994e). The proposed Phased Implementation alternative site in the easternmost portion of the 200 East Area is comprised of approximately 65 percent shrub-steppe, with the remaining area disturbed by the construction in the 1980's of the unused Grout Treatment Facility (ASI 1995).
Figure I.4.2.1 TWRS Areas Vegetation Types (Simplified)
Table I.4.2.1 Common Vascular Plants Found on the Hanford Site
Other vegetation in the 200 Areas includes wetland species associated with man-made ditches and ponds and introduced perennial grass planted to revegetate disturbed areas. Wetland species such as cattail, reeds, and various trees, such as willow, cottonwood, and Russian-olive, are established around some of these ponds (Cushing 1992). However, several of the ponds have been decommissioned, which eliminated the supply of industrial water feeding the ponds. Without the water supply, the artificial wetland habitat was eliminated. None of the wetlands or ponds are near the TWRS sites.
Introduced perennial grass, such as Siberian-wheatgrass (Agropyron sibericum), has been used extensively in the 200 Areas to revegetate and stabilize waste burial grounds against wind and water erosion. Siberian-wheatgrass has proven to be drought tolerant and better adapted to sandy soil than other species used in the 200 Area's revegetation (Stegen 1993).
At the potential Vernita Quarry borrow site, the areas at the top of the basalt cliffs have very low shrub densities, primarily big sagebrush and rigid sagebrush. Grasses such as bluebunch wheatgrass and Sandbergs bluegrass are common. Areas between and below the basalt cliffs have shrub coverage of 30 to 40 percent, primarily big sagebrush with some spiny hopsage and prickly phlox (Duranceau 1995).
The potential McGee Ranch borrow site contains a wide variety of shrubs and flowering plants. Large portions of the site are covered with a dense stand of big sagebrush and spiny hopsage. This area has a Sandbergs bluegrass understory with very little cheatgrass or other alien weed species (Duranceau 1995). Approximately 25 percent of the site is abandoned farmland and is dominated by cheatgrass and Russian-thistle. The McGee Ranch area also is an important vegetation and wildlife corridor linking the Hanford Site and the Yakima Training Center, which are two largest shrub-steppe areas remaining in Washington State (Fitzner 1992). In 1996, the Washington State Department of Fish and Wildlife asked DOE to preserve the McGee Ranch area as a wildlife corridor (Baker 1996).
The Nature Conservancy of Washington recently discovered a new species of buckwheat in the Umtanum Ridge area, which is in the same general area of the Hanford Site as McGee Ranch and Vernita Quarry ( Nature Conservancy 199 6 ).
I.4.3 WILDLIFE
Approximately 290 species of terrestrial vertebrates have been observed at the Hanford Site, including 41 species of mammals, 238 species of birds, three species of amphibians, and nine species of reptiles (Weiss-Mitchell 1992). Major terrestrial habitat types occurring on the Site include basalt outcrops, scarps and screes, riparian and riverain areas, shrub-steppe, sand dunes and blowouts, and abandoned fields (Downs et al. 1993).
I.4.3.1 Mammals
Common large mammal species include the mule deer and Rocky Mountain elk; predators such as coyotes, bobcats, and badger; and a variety of small mammals (Table I.4.3.1). Elk were not present when the Hanford Site was established in 1943 and did not appear onsite until 1972. The elk occur primarily on the FEALE Reserve, although they also may be found elsewhere on the Site, such as on the islands and along the Columbia River (PNL 1993a). Mule deer may occur almost anywhere on the Hanford Site, although concentrations are highest along the Columbia River between the Hanford townsite and the B Reactor area (Rickard et al. 1989). White-tailed deer are occasionally sighted along the Columbia River and at the Yakima River Delta near Richland (Fitzner-Gray 1991). Six species of bats also occur on the Hanford Site, primarily as fall or winter migrants, with some using abandoned buildings as roosting sites (Cushing 1992).
I.4.3.2 Birds
Bird species on the Site include a variety of raptors, songbirds, and species associated with riparian, riverain, and upland habitats. Approximately 240 species of birds, including migrants and accidental species, have been observed at the Hanford Site (Landeen et al. 1992). Of these, 36 are common species (Table I.4.3.2) and 40 occur as accidental species (Cushing 1994).
Common raptors that may occur onsite year-round are the northern harrier, red-tailed hawk, golden eagle (Aquila chrysaetos), prairie falcon (Falco mexicanus), American kestrel (Falcosparverius), barn owl (Tyle albu), great horned owl (Bubo virginianus), and long-eared owl (Anio olus) (Fitzner-Gray 1991). Raptors use a variety of habitats for nesting and foraging at the Hanford Site. Nest habitat include outcrops and cliffs, trees, marsh lands and fields, and utility towers. Depending on raptor size and species, prey may include small mammals, birds, reptiles such as snakes, and insects.
A variety of passerine (songbird) species is known to occur in the shrub-steppe vegetation type on the Hanford Site. These include the western meadowlark (Sturnella neglecta), grasshopper sparrow (Ammodramus savannarum), horned lark (Eremophila alpestris), and sage thrasher (Oreoscoptes montanus) (Downs et al. 1993). The western meadowlark and horned lark are the most abundant shrub-steppe passerine bird species that breed on the Hanford Site (Rickard-Poole 1989). The western meadowlark and horned lark nest on the ground in the open, while shrub-steppe species like the sage sparrow, sage thrasher, and loggerhead shrike require sagebrush or bitterbrush for nesting habitat.
Table I.4.3.1 List of Mammals Occurring on the Hanford Site
Table I.4.3.2 Common Birds Occurring on the Hanford Site
Common upland game bird species include the chukar partridge (Alectoris chukar), california quail (Callipepla californicus), and chinese ring-necked pheasant (Phasianus colchicus). Sage grouse (Centrocercus urophasianus) and gray partridge (Perdix perdix) are less common and rarely seen. Although once more common, sage grouse are now essentially absent from the Site, displaced after a major wildfire in 1984 (Brandt 1995). None of the upland birds are native to the area except the sage grouse.
I.4.3.3 Reptiles and Amphibians
Nine species of reptiles and three species of amphibians occur on the Hanford Site (Table I.4.3.3) (Fitzner-Gray 1991). The most abundant reptile is the side-blotched lizard (Uta stansburiana) (Cushing 1992). The short-horned lizard (Phrynosoma douglassii) and northern sagebrush lizard (Sceloporous graciosus) are also common in mature sagebrush habitats with sandy soil. Common snakes include the gopher snake (Pituophis melanoleucus), yellow-bellied racer (Coluber constrictor), and pacific rattlesnake (Crotalus viridis). Less common are striped whipsnakes (Masticophis taeniatus) and desert night snakes (Hyspiglena torquata). Amphibians on the Hanford Site are associated with riparian habitats located along permanent water bodies or the Columbia River (Fitzner-Gray 1991). Included are the Great Basin spadefoot (Spea intermontana), Woodhouses toad (Bufo woodhouseii), and the Pacific tree frog (Hyla regilla).
Table I.4.3.3 Amphibians and Reptiles Occurring on the Hanford Site
I.4.3.4 Insects
The Nature Conservancy of Washington, in an ongoing multi-year inventory project, has identified approximately 1,2 00 species of insects on the Hanford Site. This includes the discovery of six new species of bees , six new species of flies, five new species of leafhopper and planthopper insects , one new species of wasp and one new species of beetle ( Nature Conservancy 199 6 ). None of the new species were found in potential TWRS areas. However, The Nature Conservancy project focused on the FEALE Reserve, the North Slope, and along the Columbia River rather than in areas of the Site where TWRS activities may occur under the various EIS alternatives.
Table I.4.3.4 lists the relative abundance (percentage) of insect taxa collected from three shrub species on the Site. Grasshoppers and darkling beetles represent some of the more conspicuous insect groups. The populations of both of these species of insects are subject to seasonal changes and weather variations (Rogers-Rickard 1977). Fifty percent of the known insect species are of the order Coleoptera (beetles) (ERDA 1975). Many of the insect species are important in the food web of birds and mammals found onsite. Species like the darkling beetle play an important role in the decomposition process by feeding on decaying plant material, animal excrement, fungi, and live plant tissue (Weiss-Mitchell 1992).
Table I.4.3.4 Relative Abundance of Insect Taxa Collected from Sagebrush, Rabbitbrush, and Hopsage
I.4.4 AQUATIC ECOLOGY
Aquatic habitats on the Hanford Site are primarily associated with the Columbia River, two small spring-fed streams on the FEALE Reserve, and artificial ponds and ditches occurring in or near the 200 Areas. Past studies (Cushing-Watson 1974, Emery-McShane 1978, and Cushing 1994) describe the ecology of some of these ponds. The Columbia River supports a large and diverse community of plankton, benthic invertebrates, fish, and other communities. The springs are also diverse and productive (e.g., dense watercress blooms and fairly high aquatic insect populations). The artificial ponds and ditches, many of which are now abandoned and dried out, often provide lush riparian habitat and support populations of migratory and breeding birds, particularly waterfowl. No extensive discussions are provided of Site aquatic habitats because none of them are in close proximity to any TWRS sites.
I.4.5 SENSITIVE HABITATS
Sensitive habitats on the Hanford Site include wetlands and riparian habitats. Wetlands include those transitional lands occurring between terrestrial and aquatic ecosystems where the water table is usually close to the surface or where shallow water covers the surface (Cowardin et al. 1979). The primary wetlands found on the Site occur along the Hanford Reach of the Columbia River and include the riparian habitats located along the river shoreline. Other wetland habitats found on the Hanford Site are associated with man-made ponds and ditches. These include B Pond and its associated ditches located near the 200 East Area. The B Pond Complex was constructed in 1945 to receive cooling water from facilities in that area. Wetland plants occurring along the shoreline of B Pond include herbaceous and woody species such as showy milkweed (Asclepias speciosa), western goldenrod (Solidago occidentalis), three square bulrush (Scirpus americanus), horsetail (Equisetumsp.), rush (Juncus sp.), common cattail (Typha latifolia), mulberry (Morus alba), silver poplar (Populus alba), black cottonwood (Populus trichocarpa), and willow (Salix sp.) (Sackschewsky et al. 1992). Wildlife species observed at B Pond include a variety of mammals and waterfowl species (Meinhardt-Frostenson 1979).
I.4.6 SPECIES OF CONCERN
Species of concern on the Hanford Site include Federally-listed threatened and endangered species, Federal candidate species, Washington State threatened or endangered species, State candidate species, State monitor species, State sensitive plant species, and species of ethnobiological concern to Native Americans.
Species of concern occurring on the Hanford Site are listed in Tables I.4.6.1 and I.4.6.2, along with definitions of each category. No Federally-listed threatened or endangered plant or animal species occur in the 200 Areas, at the potential Pit 30 borrow site located between the 200 East and 200 West Areas, or at the potential Vernita Quarry and McGee Ranch borrow sites. (Sackschewsky et al. 1992). Pipers daisy (Erigeron piperianus), a State sensitive species, has been found at B Pond near the 200 East Area and at Pit 30. The crouching milkvetch, stalked-pool milkvetch, and scilla onion, all State Class 3 monitor species, are also found in the 200 East Area.
Wildlife species of concern observed or considered likely to be found on or near the Central Plateau include the sage sparrow (Amphispiza belli), loggerhead shrike (Lanius Ludovicianus), and Swainsons hawk (Buteo swainsoni). The loggerhead shrike and sage sparrow commonly nest in undisturbed shrub-steppe habitat. The sage sparrow is one of the most common nesting birds on the Hanford Site (Downs et al. 1993). Other bird species of concern that may be found include the burrowing owl, ferruginous hawk, Swainsons hawk, golden eagle, sage thrasher, and prairie falcon (Cushing 1994).
Nonavian wildlife species of concern using the Central Plateau and vicinity include the striped whipsnake (Mastocophis taeniatus), which is a State candidate species; the desert night snake (Hypsiglena torquata), which is a State monitor species; the northern sagebrush lizard, a Federal Category 2 candidate species, and the pygmy rabbit, a Federal Category 2 candidate and State threatened species (Rogers-Rickard 1977).
Table I.4.6.1 Plant Species of Concern on the Hanford Site
Table I.4.6.2 Wildlife Species of Concern on the Hanford Site
To understand the role of the Central Plateau in terms of ethnobiology, the role of the natural environment in a culture, it is necessary to briefly describe the subsistence life-style of the Native Americans that have long resided in the general area (Hunn 1990). The Native American people that resided along the reach of the Columbia River flowing through what is now the Hanford Site followed a seasonal, migratory life-style, as did the majority of Native American people along the Columbia River. They concentrated on salmon fishing at Priest Rapids in the summer and early fall (June through October) when weather and water conditions combined with salmon migration provided a productive fishery. In the spring, they moved towards the areas now known as Moses Lake and Ephrata to gather roots, at one time a substantial component of their diet. In the late fall, the Native Americans moved to the surrounding mountains to gather berries and hunt. In the winter they returned to lower, warmer, elevations along the river where they over-wintered in semi-permanent long-houses. Although Native Americans followed a well-defined pattern of movement throughout the year, they fished for other species when salmon were not present, hunted whenever the opportunity was available, and gathered available, edible food plants.
Affected Tribes have indicated that big game including elk and antelope were abundant on the Columbia Plateau (CTUIR 1996). Other researchers have indicated that the Columbia Plateau historically did not support large populations of big game and that it is more likely that big game hunting was associated with fall berry-gathering expeditions to areas where larger animals were more abundant (Devoto 1953 and Irving 1976) . Smaller mammals such as the yellow-bellied marmot, Beldings ground squirrel, Townsends ground squirrel, jackrabbits, and cottontails probably made up a large portion of the diet of Columbia Basin Native Americans. This has been substantiated by archeological finds along the Columbia River (Aikens 1993).
Bird species were an additional source of food for Native Americans (CTUIR 1996) . Historically, the Hanford Reach of the Columbia River has been an important waterfowl wintering and breeding area. Waterfowl were netted or shot. Egg collecting probably contributed to the Native Americans diet. Birds and bird parts were used for medicinal purposes or as a part of religious practices. Bird parts were also used as decorations and to fletch arrows. Waterfowl and sage grouse probably made up the bulk of birds used for food (Hunn 1990).
Fish have been and remain an important part of the diet of the Native Americans residing along the Columbia River. Salmon played an important role in their diet, but suckers and other bottom fish are thought to have contributed as much to the diet as did salmon (Hunn 1990 and Aikens 1993).
For the Native Americans that live along the Columbia River, salmon and other fish continue to be an important part of their diet.
Plants have been and remain important to Native Americans along the Hanford Reach. Plants or plant parts provide food, medicine, cordage, building materials, and materials of religious significance. Several dozen plant species at the Hanford Site are considered to have uses in traditional Native American cultures and lifestyles. A number of these plants species were identified in 1994 biological surveys of the TWRS sites in the 200 East Area (Fortner 1994).
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