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PROPOSED DECISION - Canadian Strip/Phase II Bond Release October 1, 1990 Page 4 class would be disruptive to cropland and forestry post-mining land use, and that the critical and severe erosional condition would be disruptive of all post-mining land uses, including rangeland and fish and wildlife habitat, the designated post-mining land use at the site. The classification system evaluates erosion condition based on seven categories: soil movement; litter movement; surface rock fragments; pedestalling; flow patterns; rills and gullies. Each category is broken into five levels of erosion. At Canadian Strip, all five of the participants present on June 6, 1990, rated the east facing slope upslope from Pond 2 to become familiar with the system following instruction from Mark Humphrey. Later, Mark Humphrey, Cathy Begej and Bill Hi11 evaluated the drainage bottom leading into Pond 2, while Jeff Zingo and Susan McCannon evaluated the west facing slope above Pond 2. Cathy Begej evaluated the areas reclaimed prior to 1987. The results are shown on Table 4. Most evaluations rated the Droperty as having a "slight" erosional condition. Usually, only five of the erosion condition categories were observed. Very few pedestals or gullies were found at the site. An effort was made to distinguish between recent, active erosion and past erosion. For instance, it was assumed that a highly revegetated rill was formed in the first year, before any vegetative growth appeared. This rill would not be counted as an erosional feature. Clumps of grass on hill slopes frequently showed some soil deposition upslope and 1/4" to 1/2" of exposed roots on the downslope side. This feature was evaluated in the soil movement category. Raindrop imprints were visible on clumps of dirt or areas without vegetative cover. Wyoming Fuel Company had used large, 2" wood chips as a mulch. These were frequently aligned between drill rows or in the bottom of rills found on slopes. Recent movement of wood chips was assigned to the category of litter movement, along with all other organic matter but scat (antelope pelletsl. TABLE 4: Summary of Erosional Stability Observations Identified Possible Erosion Factor Factor Percentage Condition Class East Facing Slope N/A N/A 20-40 Slight West Facing Slope Observer 1 14 71 20 Stable Observer 2 38 85 44 Moderate Palley Bottom Observer 3 13 71 18 Slight Observer 4 16 43 37 Slight Northern Part of Property 12 12 17 Stable