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RN07 Page 6 5/30/18 2.04.7 Baseline Hydrologic Conditions - A review of surface water related sections of Rule 2.04.7 was conducted. The following questions pertain to Exhibit 32: 15. Describe to what extent Foidel Creek Mine has been able to improve winter water quality and quantity data collection in affected reaches of the Yampa as related to conclusions 1 a, b, and c drawn in Exhibit 32. 16. Describe to what extent a review and update of site-specific regression functions as per conclusion 2 has been undertaken. 17. Please state if additional nodes in the streamflow system have been added or modified. If additions or modifications occurred, please state through what permitting action changes were made. (Conclusion 3). 18. Please state if a critical review of stream standards, as per conclusion 4 has taken place. 19. If a review of stream standards occurred please describe the results of this review and cite, or submit to DRMS, the pertinent document. Response: - It should be noted that Exhibit 32, Quantity and Quality Modeling Analysis of Surface-Water Resources of the Trout Creek Basin, was completed in early 1985 to provide a preliminary baseline characterization of surface water conditions in the Trout Creek Basin as the basis for mine permitting and future impact analysis. In the intervening 30+ years, TC and predecessor companies have conducted extensive ongoing surface and ground water monitoring and analysis to both characterize actual current conditions and identify and evaluate any significant observed changes. The adequacy comments (14 – 18) generally focus on recommendations in this original report to update and calibrate the model. While the model was useful for initial characterization, the actual ongoing monitoring data and related analysis provide a more useful and practical basis for characterizing and evaluating surface water quantity and quality in the Basin. This data and related analyses are summarized in the Annual Hydrology Reports. TC’s current, approved hydrologic monitoring plan (Exhibit 14 – Revised by TR’s 38 and 42; and MR’s 48, 66, 73, 76, 85, 98, 113, 177, 180, 267, 279, and 281) includes five surface water monitoring stations on Foidel Creek, nine surface water monitoring stations on Fish Creek, one surface water monitoring station on Middle Creek, and three surface water monitoring stations on Trout Creek. The furthest downstream site on Trout Creek (Site 1005) serves to monitor any conditions that would potentially impact the Yampa River. Through our involvement in the Water Quality Control Commission triennial basin hearings, we have been involved in an ongoing program to evaluate both water quality and aquatic life in the Basin, including characterization of ambient conditions and evaluation of stream standards. This program has resulted in filing petitions and participation in hearings to modify the stream standards for specific segments, obtain temporary modifications, and establish site -specific ambient-based standards. This process is ongoing. Resolved 20. Baseline characterizations of the Wadge Coal/Wolf Creek Coal Interburden and the Wolf Creek Coal Seam were established with the approval of TR-83 as well as the Wolf Creek Reserve monitoring plan in Exhibit 14A. The development of the Wolf Creek Reserve has lowered the poteniometric surface elevation in the Wadge overburden. Figure 06s Potentiometric Surface Wadge Coal Overburden and Figure 11d Wadge Overburden Potentiometric Surface and TDS Concentrations are no longer representative of the current mine plan and