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Geology -Rules 2.04.5 and 2.04.6 A detailed description of the geology of the permit azea and adjacent area is contained under Section 2.04.6, of the permit document. Additional information on the geology of the permit area and adjacent azea is shown on Map 2, Mine No. 3 Geology; Map 3, Geologic cross-sections; Map 21a, Detention Basin cross-sections; Exhibit 1; Tables 1, 2, 3, and 4; and Figures 1 and 2. The proposed permit area lies on the southeastern flank of the Twentymile Pazk Structural Basin. The basin is a synclinal extension of a much lazger basin to the northwest, [he Washakie-Sand Wash Structural Basin. The syncline forming the basin is a doubly plunging, north-south trending syncline known as the Twentymile Pazk Syncline. The only major structural feature existing on site is a 200 foot wide fault zone. The zone lies to the west of the proposed mining azea and trends northwest -southeast. It has a normal type displacement of 60 to 100 feet. Four geologic formations exist in the vicinity of the proposed Mine No. 3. They aze, in ascending order, the Mancos Shale, the Iles and Williams Fork Formations of the Mesaverde Group, and the Lewis Shale Formation (Figures 3 and 4). These strata were all deposited during the late Cretaceous Period. Generally, the strata dip to the west at 8 degrees to 14 degrees into the Twentymile Pazk Basin. Three mineable coal seams, the Lennox, Wadge, and Wolf Creek coals, are located within the Williams Fork Formation. The Wadge coal seam was mined at Mine No. 3. Results of chemical analyses of overburden samples from Mine No. 3 are presented in Table 4, Overburden Chemical Data. The applicant has included overburden geochemical analyses from five drill holes within the proposed permit area; geographic and vertical sampling density aze in accordance with State guidelines for overburden geochemistry sampling and analysis. No acid-forming, toxic-forming or alkalinity producing material have been identified. No data are available in the permit application on chemical analysis of the Lennox Coal Seam. This coal seam, which is known to be somewhat high in pyritic and organic sulfur content in the Twentymile Park Basin, occurred in the western portion of the surface mined azea, and was spoiled with the overburden. Given the small quantities of the Lennox coal seam which was spoiled (a rough estimate is 5% or less of the total overburden in the mined area), no reclamation problems associated with the Lennox were anticipated and none have been exhibited. For these reasons, lack of site-specific data for the Lennox is not considered a significant environmental concern. Climatological Information and Air Resources -Rules 2.04.8, 2.05.4(2)(h) and 2.05.6(1) Climatological information for the permit area is found in Section 2.04.8 of the permit application. An air pollution control plan is presented in Section 2.05.6. The air emission permit is in Exhibit 9 of the permit application. 5