2022-09-14_REVISION - M2020065 (2)

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Over the life of the mine, a total of approximately 666,000 CY of material will be extracted at a rate of roughly 66,000 CY per year. This will result a mine life of approximately 11 years (10 years of mining, one year of reclamation completion), depending on market conditions. 2. Disturbance Area The largest disturbance at any one time for this mining operation will be strictly limited to 15 acres of total disturbance. This area will require topsoiling and seeding. The disturbance area will be staked onsite prior to topsoil stripping. This is less than the total affected area of 319.8 acres, which is shown on Map C-2. Concurrent reclamation practices prevent the creation of the maximum disturbance area by reclaiming areas as mining progresses. See Exhibit L for a detailed discussion of the reclamation costs and bond calculations that are based on this point in the mine's life. 3. Deposit and Underlying Stratum Geology A soil report was generated using the United States Department of Agriculture's Natural Resources Conservation Services' (NRCS) Web Soil Survey (WSS)' and is included with this permit application (Exhibit I Soil Report). The soil survey encompassed the approximate boundaries of the permit area. While five soil types were mapped, the Gunbarrel, Kerber, Mosca, San Luis, and Space City. All five are similar and are described in part as containing loamy sand or sandy loam. The Gunbarrel and the Mosca comprise 95% of the permit area and will be discussed in more detail. The Gunbarrel is a saline, loamy sand and comprises 61.7% of the mapped soil survey. The Mosca is a loamy sand and comprises 33.3% of the mapped soil survey. Both the Gunbarrel and the Mosca report depth to a restrictive feature and depth to water table of more than 80 inches. Because mining will only occur to a depth of 6 feet (72 inches) it is anticipated that no bedrock will be encountered. The water table is currently approximately 15 feet below the surface in the permit area. Should the water table be encountered during mining, four feet of backfill will be placed in the affected areas. The main applicable United States Geological Survey geologic map for the site is from 1979. The area of the Mystic Soil was mapped by Tweto (1979)2 as consisting of unconsolidated Quaternary-Tertiary alluvium, sand, and gravel (Holocene) underlain by the Alamosa Formation. httr)s://websoilsurvey.sc.egov.usda.gov/App/HomePaae.htm. 2Tweto, O. (1979). Geologic Map of Colorado 1: 500 000. US Geological Survey. Mystic Soil November 2020 D-5 Lewicki&Associates