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RN07 Page 19 5/30/18 permits have been consolidated in Exhibit 30, and the Table of Contents has been updated. All updated or revised materials relating to this comment accompany these responses for insertion or replacement in the PAP. Resolved 2.05.6(3)(a)(i), (iii), and (iv) – Protection of the Hydrologic Balance 53. Sampling frequency issues pointed out in the DRMS Review of the 2014 Annual Hydrology Report, specifically items 11 and 16 concerning Exhibit 14. TCC will need to address any item where a specific monitoring requirement was not met. Please either submit the data or explain why the data was not collected. Please also address any inconsistencies in sampling frequencies for 2015-2017. Response: - TC responded to the Division’s comments on the 2014 Annual Hydrology Report by letter dated 05/04/16 (copy attached for reference). With the exceptions of adverse field conditions which precluded field data collection prior to mid-April, changes in stream conditions affecting data accuracy (Sites 8 and 900), the noted problems with a gauging station (Site 27A), and questions about the continued need for the Jones well, the response addresses the Division’s stated questions or concerns. Despite efforts to eliminate the beavers upstream of Sites 8 and 900, they have persisted, so the same considerations apply to ongoing monitoring for these sites. TC has continued to conduct direct monitoring of flows for Site 27A and the upstream site (Site 305), where ongoing stream erosion and livestock use are considerations relative to re-establishment of regular gauging stations. TC is currently in negotiations with the owners of the Jones Well to try to establish a good long-term water supply from a deep groundwater aquifer, and the outcome of these efforts will determine whether or not the Jones Well will need to be maintained as a monitoring well (Jones water supply well is not currently being used as TC is providing hauled water to a cistern). Resolved 54. TC will need to evaluate the concerns identified in item number 24 of the DRMS Review of the 2014 AHR data and the PHC (section 2 05 6 3 of the permit) regarding surface hydrology impacts. TC will need to address the following item: a. For the lower reaches of Middle Fish and Trout Creek, the projected average conductivity sulfate and TDS levels for 2009 to 2015 contained in Exhibit 32 do not appear to be reflective of the average levels reported in the 2014 AHR. The averages reported for these parameters exceed the average projected amounts. TC will need to evaluate these constituents and update the Probable Hydrologic Consequences section of the permit and assess the negative impacts of these elevated constituent levels. Please include current data up through 2017 in this update. Response: - In order to address this comment, it is important to understand the purpose, intent, and limitations of the referenced water quality projections presented in Exhibit 32. Exhibit 32 is a report prepared by In-situ Inc. in 1985, which utilized modeling to characterize ambient conditions and project future water quality in area drainages, based on limited baseline flow and water quality data, regression analysis, and specific assumptions and methods, as stated in the report. The report reflects modeling (projected) results for four, 8 -year periods extending from 1985 through 2017, and uses eight years of pre-mining data (1976 – 1985) as a check to calibrate the model predictions. For Lower Middle, Fish, and Trout creeks, Exhibit 32 acknowledges specific considerations relating to the accuracy and use of modeling results for EC, TDS, and sulfate (Exhibit 32, pgs 31 - 33).