2020-08-20_REVISION - C1980007 (36)

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The mountains of the Continental Divide provide an effective barrier to the movement of moisture-laden air that reaches the eastern slope of the Rocky Mountains from the Gulf of Mexico. Under this influence, two basic types of climate, semi-arid and undifferentiated highlands, are characteristic of the general area where the mine is situated. Temperatures can range below freezing in the winter, and yet in the summer, with the exception of higher elevations, can be extremely warm. The precipitation that does fall, originates from the Pacific Ocean weather systems, and most frequently occurs in the winter. Average annual precipitation ranges from approximately ten inches along the North Fork of the Gunnison River and the lower portion of Minnesota Creek to as much as 24 inches on the flanks of Mount Gunnison. The majority of precipitation falls as snow during the winter months, while the sparse summer precipitation consists of isolated thunderstorms. Soils - Rule 2.04.9 Soil Resource Information can be found in Section 2.04.9 in the permit document. More specific information relating to soil mapping units can be found in Exhibit 27, Exhibit 28, Exhibit 29, Exhibit 30, and on Maps 40 and 41. Soils of the West Elk Mine were mapped during the summer of 1976. Throughout the soil survey, "mapping units" were used to characterize the soils in the mine area. These survey mapping units are combinations of Soil Families or selected Great Groups and Subgroups according to the system of soil taxonomy used in the National Soil Survey Program of the United States. During the summer of 1993, the soils of the Jumbo Mountain Tract were mapped utilizing criteria and descriptions contained in the Soil Conservation Service soil survey of the Paonia, Colorado area(USDA-SCS, 1993). The maps have been updated for subsequent permit revisions. Any discrepancies in soil mapping units can be attributed to the change in soil classification during the time between the mapping efforts. The survey is a general reconnaissance and the mapping units are broad in concept. Vegetation- Rule 2.04.10 Specific information regarding collection and analysis of vegetation can be found in Section 2.04.10 of the PAP. The distribution of the land and vegetation types can be found on Maps 42 and 43 of the PAP. The West Elk Mine collected baseline vegetation information in 1975, 1976, and 1993 for a study area which extends approximately one mile outside the permit boundary and mine plan boundary. This area is approximately 25,560 acres in size. This survey identified ten vegetation types and six land types. They are as follows: 1) Aspen, comprising 19 percent of the study area; 2) Douglas fir, comprising four percent of the study area; 3) Wet Mixed Shrub, comprising 50 percent of the study area, dominated by serviceberry and Gambel oak; 4) Dry Mixed Shrub, comprising 10 percent of the study area, distinguished by serviceberry, Gambel oak, Mountain mahogany, Cliff findlerbush, and bitterbrush; 5) Oak, comprising one percent of the study area, including Gambel oak and the larger size oak individuals (15-20 ft in height), which are limited to the bottom of permanent stream drainages; 6) Juniper, comprising five percent of the study area, which includes Rocky Mountain Juniper and Utah Juniper; 7) Riparian, comprising two 21