3.1 Introduction
The National Wildlife Area (NWA) encompasses 458 km² of prairie grassland including sand hills, ancient glacial coulees, and the riverbank and breaks along the South Saskatchewan River valley. From an ecological perspective, the area is found within the Dry Mixedgrass Subregion of the Grasslands Natural Region of Alberta (Natural Regions Committee 2006).

3.2 Physiography
The landscape within the NWA is dominated by three broad physiographic units, the Eastern Alberta Uplands, the Eastern Alberta Plain, and the South Saskatchewan River Valley (Pettapiece 1986). The terrain associated with the Eastern Alberta Uplands is regionally characterized as hummocky to rolling. Locally, surface relief is generally limited to a maximum of 30 m but more typically is 10 m (Shetson 1990). The Eastern Alberta Plain tends to have relatively level- to-undulating topography and occurs only in the southern one-fifth of the study area. This physiographic unit includes steep sided, often poorly vegetated valley walls; discontinuous terraces that range from current to early post-glacial age; and the present day South Saskatchewan River. Relief within the valley ranges up to about 150 m.

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3.3 Surficial and Subsurface Geology
The surficial deposits in the study area tend to be complex. Based on maps prepared by Berg and McPherson (1972) and Shetsen (1987), air photo interpretation and field observations, the uplands of the study area appear to be dominated by stagnation moraine with till of uneven thickness. Local occurrences of water-sorted material up to 30 m thick are found along with areas of Aeolian deposition and erosion (Adams, et al, 1997).

CFB Suffield is underlain by the Oldman Formation, which is characterized by sandstone bedrock of nonmarine origin. This geological unit is described as pale grey, thick bedded, medium to coarse-grained feldspathic sandstone; grey clayey siltstone; green and grey mudstone; dark grey and brown carbonaceous shale and ironstone concretionary beds. (Hamilton et al. 1999). This formation is classified as Upper Cretaceous and has an overburden of drift varying in thickness from areas with less than 15 m in several locations, to thicknesses approaching 140 m in some areas (Alberta Government 2003).

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3.4 Climate
The Project area is characterized by a semiarid continental climate with warm summers and cold winters (Alberta Government 2003).

The mean annual temperature is about 2.8 degrees Celsius. July, the warmest month averages about 20 degrees Celsius, and January, the coldest month has a -13 degrees Celsius average. The growing season (average daily temperature above 5 degrees Celsius) lasts about 183 days beginning around April 16. With a frost-free period of about 115 days, there are about 1850 growing degree-days above 5 degrees Celsius.

The Project area receives an average annual precipitation of roughly 335 mm, most of which falls between May and September. Due to the temperature regime annual evapotranspiration is in the order of 365 mm resulting in a yearly moisture deficit of about 30 mm (Environment Canada 2000; Pettapiece 1989),

3.5 Soil Landscapes
The soils in the Project area were aggregated into 13 Soil Landscape Features (SLFs) based on parent materials, surface form, soil texture, soil classification, topsoil depth, and slopes.

Choppy Sandhills, sand dunes of moderate to high relief, make up the greater part of the northern NWA. The soils found in these areas are primarily Brown Chernozems, typical grassland soils, with inclusions of shallower eroded soils. These soils have formed in coarse deposits with loamy sand to sandy textures. Toward the mid and western parts of the northern NWA, the Sandhills grade into Sand Plains of low to moderate relief. The soils found in this region are also coarse textured Chernozems.

The southern NWA is characterized, in its northern half, by complexes of Till Plains that are dissected by either channels or gullies - the latter found mainly on steeper slopes along the South Saskatchewan River. While the soils here are also grassland Chernozems they have formed, for the most part, in finer textured glacial till deposits (loams to clay loams). The south part of the southern NWA is occupied mostly by Sand Plains with, as in the northern NWA, coarse sandy soils.

Both the northern and southern sections of the NWA have smaller areas of many of the other SLFs but the only one of significant extent is the Majority of Other Soil Landscapes. This grouping of miscellaneous features is characterized principally by undulating to hummocky landscapes with low to moderate slopes. Soil parent materials are generally medium to moderately fine-textured (loam to clay loam) glacial till or glaciolacustrine (clay loam) veneers (shallower than 1 m) or blankets (deeper than 1 m) that overlay the till. Some areas also show moderately coarse textured glaciofluvial veneers overlying the finer till or glaciolacustrine deposits. Wetlands are typically found in depressional locations where the finer textured materials impede drainage.

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3.6 Vegetation and Wetlands
The Project area lies within the Dry Mixed Grass Ecoregion of southeast Alberta. Vegetation is characteristic of the short grass prairie region, where the main grasses are blue gamma grass (Bouteloua gracilis) and common spear grass (Stipa comata). Sage (Artemesia sp.) is the dominant shrub species, particularly in areas of overgrazing. Trees occur only in the river valleys and in irrigated areas. Approximately 418 vascular plant taxa have been identified within CFB Suffield. Vegetation is characterized by a matrix of large tracts of upland grassland and mixed grassland/low shrubland punctuated with smaller, isolated habitats. The CWS classified and mapped 34 vegetation cover types in the NWA, Koomati, Falcon and Nishomoto Flats areas and 28 of these cover types individually occupy less than 2% of the total land area. These uncommon vegetation cover types are characterized primarily by moist/wet soil conditions, tall shrub and tree cover, or areas dominated by naturally exposed soil which often support a divergent assemblage of plant and animal species.

A number of rare vascular plant species and rare plant communities have been recorded in the Dry Mixedgrass Ecoregion whose preferred habitat may occur within the Project Area. These include 41 provincially rare taxa, of which 8 are nationally rare in Canada, in addition, 13 provincially rare species and 40 locally rare taxa are endemic to the CFB Suffield Block (Environment Canada 2004b).

There are three dominant land uses in the EIS local study area (LSA) that have affected vegetation communities: military training, shallow gas development and livestock grazing. They occur in various combinations depending on geographic location. Over 80 percent of the southern half of the NWA supports livestock grazing. The northern half of the NWA supports only shallow gas development and no grazing. The MTA portion of the LSA and RSA supports predominantly military and oil and gas activity and a small amount of grazing. East of the Saskatchewan River, the Koomati block supports oil and gas and grazing but very limited military activity. Well densities vary, with the south area of the MTA and Koomati supporting mainly 16 wells per section (wps); the majority of the central and north area of the MTA has 8 wps; and the north area of the NWA mostly has 4 wps. With the exception of the D6/D8 area, the south area of the NWA supports 8 wps.

Existing wetland conditions were described and mapped in the NWA by the CWS in the mid-1990s. Wetlands have also been mapped by EnCana as part of its CFB Suffield constraints mapping program and by the DND. Mapping methods varied between each of these three Projects with CWS mapping being the most detailed. Twelve (12) individual wetland types were identified by CWS that occupy 210 ha or less than 0.5% of the NWA. The vast majority of wetlands occur within the southern portion of the NWA where 8 of the 12 types of wetlands cover 182.3 ha of land. Landforms that support the greatest number and area of wetlands in the NWA are moderate to high relief morainal and glacio-fluvial deposits. The many depressions, flats and glacial drainage channels in these areas contain fine-textured silt loam or sandy clay-loam soils, which have higher water holding capacities and provide favourable sites for wetland development.

3.7 Wildlife and Wildlife Habitat
A majority of the Project area is within Wildlife Key Areas for antelope and white-tailed deer while the north of the Project area is a key Ungulate area for mule deer (Alberta Fish and Wildlife 1985). The Project area is also located within migratory bird habitat subregions as defined by Poston et al. (1990) for burrowing owl and ferruginous hawk. These subregions are landscape divisions based primarily on soils. However, they are also distinct because of elevation, relief, landform, drainage and general substrate.

There are no Parks and Protected Areas of Alberta within the Project area.

There are 48 listed species identified by Alberta Sustainable Resource Development (ASRD) or the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) as resident (i.e., non-migrants) and expected to occur in the Suffield RSA. This includes 48 species: 32 birds, 8 mammals, 3 amphibians and 5 snakes.

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3.8 Hydrologic Resources
The South Saskatchewan River defines the eastern boundary of the NWA and is the most prominent surface water feature in the Project area. The interior of the NWA occupies a headwater ridge, with distributed flow to multiple receptors. There are approximately 27 mapped drainages, which consist of steep gullies that are incised into the west valley wall of the South Saskatchewan River, and an additional 17 drainages that end at terminal closed depressions with no surface outlet. The interior basins are very small, with tributary basin areas typically less than 10 km².

From a local drainage perspective, the NWA is in the driest part of Alberta, and the interior drainages are normally dry except for a brief (typically two-week) period of snowmelt, usually in March lasting for one or two weeks. Based on a representative natural basin stream gauge station, it is expected that surface runoff in the interior portion of the study area would occur in only about 75 percent of all years. Runoff can occur in response to intense rainfall events during the summer months, but such occurrences are rare. The near-absence of local area surface runoff is perhaps the most notable hydrologic characteristic of the study area.

Water requirements for the Project are expected to be met through a combination of groundwater withdrawals from within the LSA and surface water withdrawals from the South Saskatchewan River either by direct withdrawals, through purchases from the City of Medicine Hat, or from dugouts within CFB Suffield.

3.9 Land Uses
The Suffield area was sparsely occupied by ranchers and homesteaders predating 1941. Only a very small percentage of the land was cultivated, and these lands reverted to prairie as homesteads were abandoned and population of the area declined. Use of the Suffield Block lands for military research began in 1941 with CFB Suffield, one of the largest army training bases in the Western world, being established in 1971. In 1975, EnCana (formerly AEC) initiated resource development at CFB Suffield as the area was recognized as comprising, a measurable source of sweet natural gas. Oil and gas development, military activities and cattle grazing have been concurrently conducted in this area for more than 30 years. Close cooperation and communication among EnCana, DND, PFRA, regulators, other agencies and local ranchers have allowed this unique sharing arrangement to work for the benefit of all parties. Cattle grazing has continued within CFB Suffield since the 1960s. In the NWA, grazing occurs only between June and October and is limited to the southern portion of the NWA.

Stringent security and safety protocols are in effect for access for CFB Suffield (including the NWA) preventing public access. There are no communities within the NWA.

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