2023-01-05_REVISION - C1981019 (13)

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has the potential to negatively impact alluvial groundwater. Therefore, Colowyo has established three groundwater points of compliance for the Mine at MC-04-02 (Collom Gulch), MLC-04-01 (Little Collom Gulch), and MJ-95-01 (West Fork Jubb Creek). Stipulation 7 for Colowyo, requiring an analysis to determine the need for a point of compliance in alluvial groundwater below the existing Mine (for example, in the alluvium connected to Good Spring Creek), remains in place. IV. Topsoil Rules 2.04.9, 2.05.3(s), 2.05.4(2)(d) and 4.06 The Permit has been found to be in compliance with Rules 2.04.9, 2.05.3(s), 2.05.4(2)(d) and 4.06 with regard to the protection of topsoil resources. The Division has approved alternative procedures for topsoil protection following removal based on a demonstration that such alternative procedures will provide more protection for the topsoil (Rule 4.06.1(2)). A. The Soil Resource A summary of the soil resource is found in the Description of the Environment section of this document. Detailed information is presented in Section 2.04.9 and Exhibit 9 of the original PAP volumes for the original permit area, while a detailed soil description information for the South Taylor and Lower Wilson expansion areas is contained in Section 2.04.9 of Volume 12 and Exhibit 9 of Volume 13 of the PAP. Order III (generalized) soil mapping for the permit area is presented in map 5A of Volume 14 of the PAP; more detailed Order II soil mapping for the South Taylor and Lower Wilson areas is presented on Maps 5B and 5C of the PAP, respectively. Baseline information presented in the application for the South Taylor expansion area is drawn largely from a 1984 report titled "Soil Inventory-Danforth Hills Project, Rio Blanco and Moffat Counties," prepared for Consolidation Coal Company by certified professional soil scientist James P. Walsh. The Walsh report is included as Exhibit 9, Item 7, of Volume 13 of the PAP. The three major soil types at the Mine's East Pit and West Pit areas are the Work Loam, the Burnette Loam and the Campspass Fine Sandy Loam. The Work and Burnette units are generally deep, loamy textured soils with moderate permeability and high available water capacity. The physical and chemical properties of these two soils are well suited for reclamation use. The Campspass soil, however, is characterized by a shallow sandy loam A horizon less than six inches in depth. The B horizon is a heavy clay loam with hard columnar structure, which Colowyo does not propose to salvage due to the sticky, plastic properties which make it less desirable for reclamation. If spread directly on regraded spoils, the clayey soil could hamper vegetation establishment due to the slow permeability and resultant droughtiness. In addition, surface runoff from such soils would be rapid and erosion hazard would be high from both wind and water. The most prevalent soils in the South Taylor area include Burnette, Work, Lamphier, Rhone, and Northwater Loams. These are borolls, which developed from residuum or colluvium on gently sloping to rolling ridgetops, moderately steep sideslopes, and in gently sloping, concave narrow stream valleys. Shallow, rocky soils of the order entisol occur to a limited extent within the area Proposed Decision and Findings of Compliance January 5,2023 Permit Renewal No. 8 P a g e 143