2016-05-04_PERMIT FILE - C1982056 (7)

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of the proposed mining in the WCR, does not show any changes that can be attributed to the previous mining and subsidence (refer to TC's recent Annual Hydrology Reports). In order to validate that no impacts will be realized to the AVF located downstream of its planned WCR operations, TC will continue to utilize its current downstream surface and alluvial water monitoring stations. Based on current mining plans, there is the potential that Station 900 may be impacted by mining -related subsidence in mid -2022. In order to address any potential downstream impacts from the planned mining operations, TC will relocate Station 900 (will become Station 900A) and the associated monitoring equipment downstream to the previous location of Station 304 at least one year prior to any mining -related impacts on Station 900. This will allow collection of a full year's monitoring data prior to any site impacts. These stations are presented on Map 13A, Hydrologic Monitoring Program. The stations will continue to be monitored under the existing monitoring schedule as described in the Wolf Creek Reserve — AVF Monitoring Program, Exhibit 4E-11. TC is the immediate downstream user of irrigation water, and does not foresee any impacts to its agricultural operations due to the potential loss of water from the system. In the unlikely event that significant losses occurred during the irrigation season, TC has sufficient water rights to augment any loss. The two primary landowners that would potentially be affected by the undermining and subsidence of portions of Fish Creek, Foidel Creek, and the associated AVF areas are the State of Colorado and Camilletti and Sons. Camilletti and Sons, own approximately 920 acres in the immediate area of the mine, 3,500 additional acres in T6N, R86W, and approximately 1,040 acres in T7N, R86W. The State of Colorado owns roughly 4,400 acres within portions of the Fish Creek drainage area which have been or will be affected by mining. TC is also a significant landowner within the Fish Creek drainage, and Camilletti's lease grazing lands from both TC and the State. The limited areas that would potentially be affected by mining -related subsidence (ie: maximum of 75 acres potentially flooded under normal or high water conditions) is insignificant, given the total acreage of undeveloped rangeland available and currently utilized for active grazing operations. In addition, limited increases in more productive bottomland vegetation would be anticipated from both subsidence and localized increases in sub - irrigation, potentially increasing available forage and livestock carrying capacity for the affected lands. Personal communication with Mr. Frank Camilletti of Camilletti and Sons indicates that the acreage that would potentially be impacted by mining and subsidence in the WCR is not critical to their ongoing ranching operations, that subsidence -related surface effects would not be expected to result in material damage, even under worst-case conditions, and would potentially result in increases in more productive bottomland vegetation. TC's planned mining and any associated subsidence of portions of Fish Creek, Foidel Creek, and the associated AVF areas will not impact those AVF's located in the areas overlying or downstream of the operations. Any potential subsidence of the valley floor above the WCR mining area will result in the temporary formation of pooled areas similar to those which formed during undermining in the Eastern and Northern Mining Districts. These localized and temporary impacts will not significantly affect ongoing grazing operations, and may in fact, increase productivity and availability of water for livestock due to conversion of some adjacent upland vegetation to bottomland and minor increases in drainage surface areas. TC is not proposing any modification or reclamation activities for the flooded areas. PR 14-10 2.06-25.9 09/17/15