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Climatological Information and Air Resources - Rules 2.04.8, 2.05.4(2)(h), 2.05.6(1), 4.17 <br /> Climatological documentation is presented in Section 2.04 of Volume 1 and in the Climatology <br /> and Wind Direction Appendix, Volume 9 of the PAP. BRL has also provided copies of all <br /> emissions permits from the Colorado Department of Public Health and Environment, in Volume <br /> 9 of the PAP. Climatological data for the North Fork region (the area within the watershed of the <br /> North Fork of the Gunnison River) is available from Paonia, three miles due south and 1,500 feet <br /> lower in elevation than the mine site. The average annual temperature is 49.0°F at Paonia, with <br /> an average monthly mean of 24.5°F in January and 71.9°F in July. At Paonia, the annual <br /> precipitation in recent years has varied from 10 to 21 inches (Table 3 in the 2021 Annual <br /> Hydrology Report(AHR)). <br /> The local climate of the North Fork area is strongly influenced by microclimatic features - slope <br /> aspect, elevation, soil type, soil moisture content and vegetation. The steepness of the terrain, <br /> together with the type and amount of vegetation, and the orientation and range of elevation, are <br /> the major controls of the diurnal wind patterns. The shape and orientation of the North Fork valley <br /> is such that the drainage (or katabatic) flow is the dominant flow for most hours of the day. <br /> Prevailing winds are from the south-southeast, with wind speeds of ten miles per hour occurring <br /> in June. Below Paonia, the wind speed appears to decrease sharply as the air spreads over the <br /> lower valley. Because of this strong drainage wind, frost pockets are not allowed to form, thus <br /> creating a favorable microclimate for fruit tree farming. <br /> Geology- Rules 2.04.5 and 2.04.6(2) <br /> Information on local and regional geology can be found in the PAP Section 2.04.6 of Volume 1. <br /> Maps 2-1, 2-2, 2-7,2-8, 2-11,2-12 (Volume 2) and 6A-8 (Volume 6A) identify pertinent geologic <br /> features. Waste rock geotechnical analyses can also be found in Volume 6A. <br /> BRL has mined the D seam of the Upper Coal member of the Mesaverde Formation. The seam <br /> ranges in thickness from 2 to 21 feet in the permit area, with one split ranging in thickness from <br /> 151/2 feet to several inches. The coal dips 4° to 7°to the northeast. Two high-angle, normal fault <br /> zones are found in the area with displacement ranging between I and 50 feet(Map 2-8 in Volume <br /> 2 of the PAP). The earliest fault system trends N65°E and dips 70' to 80' with displacements of <br /> 2 to 6 feet. The other fault system trends N35°W and dip 70'to 80°to the northeast. The geology <br /> is further modified in the northeast corner of Lease C-37210 where coked coal gives evidence of <br /> igneous activity associated with the Miocene Iron Point pluton. <br /> The Somerset Coal Field lies on the southeast margin of the Piceance Basin and just south of Grand <br /> Mesa. The sedimentary strata exposed in the Somerset Coal Field dip at 3° to 5°to the north and <br /> northeast, and range in age from late Cretaceous to early Tertiary. <br /> Coal is produced from the Mesaverde Formation, a 2,500-foot-thick sequence of sandstone, shale <br /> and coals overlain by the Ohio Creek conglomerate and underlain by the Mancos Shale. The <br /> Mesaverde Formation is composed of four members which are, in order of decreasing age, the <br /> Rollins Sandstone,the Lower and Upper Coal members and the Barren member. <br /> 6 <br />