2013-11-27_REVISION - M1990057 - Laserfiche WebLink

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Mr. Michael Cunningham CDRMS November 26, 2013 Response: Our understanding is that Exhibit A requests the coordinates of the mill building whereas the application document requests the coordinates of the mine gate (in this case the mill gate). UMC provides both coordinates as follows: Mill Building - N39 °13'50.33 ", W106 °19'58.48 ", and Mill Gate - N39 013'44.53 ", W106 019'51.12 ". No changes are proposed for the permit documents. 6.3.2 Exhibit B - Site Description 3. The Applicant has provided comments from the Division of Wildlife (DOW) dated July 1, 2011. The Division notified Union Milling Company that the Leadville Mill would be a Designated Mining Operation (DMO) on November 23, 2011. Was the DOW aware, at the time their comments were issued, that the facility would operate as a DMO? Response: No. Lake County contacted DOW directly, shortly after UMC applied for the CUP (June 2011). UMC addressed all DOW comments in the CUP process, and the CUP was approved 7 September 2011, before it was known that a DMO operating designation was required. The information Lake County would have provided DOW included TSF and other design features along with operating criteria for the Leadville Mill which had not changed from the TR -03 documents already provided to CDRMS. Therefore UMC did not believe it necessary that DOW be re- notified. 4. Section 3.4 states the soil at the site is generally less than 6 inches thick. However, Section 3.7 states the soil is less than 5 feet thick. The Division assumes this was typographical error, please clarify this discrepancy. Response: Section 3.4 references top soil which is generally 6in thick, whereas Section 6.7 references all soils above bedrock. The statements were confusing because "soil" was used in both references. Section 3.4 will be rewritten to read as follows: "The mill sites soils, as described USDA - Salida, Colorado District office, were formed on glacial outwash sedimentary rock with slopes ranging from 3% to 35 %. Leadville soil is very deep and well drained. If formed in glacial outwash. Typically, the surface layer consisted of dark grayish brown sandy loam 1 in thick. The subsurface layer is pink stony sandy loam Tin thick. The subsoil is extremely stony clay loam 32in thick. The substratum is extremely stony loam to a depth of 60in or more. The soil is medium acidic to a depth of 8in and slightly acidic and neutral below that depth. Permeability is moderately slow, and available water capacity is moderate. Surface runoff is medium to very rapid, and the hazard of erosion of unprotected soil by water is moderate to very high. Areas that have been historically cleared (roads, benches) show very good re- growth without fertilizer or other amendments." The first sentence of the third paragraph in Section 3.7 will be changed as follows to be consistent with Section 3.4: "A thin veneer of soil with a moderate to high permeability generally 8 -9ft thick overlies the bedrock. However substratum stony loam material in excess of 25ft was encountered during construction of the TSF."