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Table I presents a summary of hydrologic monitoring requirements for these sites under TC (modified from <br />TRO1-32, Appendix D of the TC monitoring plan). Field parameters are outlined in Table 2. Water quality <br />monitoring includes field parameters (Table 2), surface water quality parameters (Table 3), and CDPS <br />parameters (Table 4), which is the monitoring requirements page from CDPHE CDPS permit CO -0042142. <br />3.1 Groundwater Monitoring <br />3.1.1 Bedrock Wells <br />Three sandstone aquifers are found beneath the subject site. In ascending order, they are: Trout Creek <br />Sandstone, Middle Sandstone, and Twentymile Sandstone. The Eagle No. 5 and Eagle No. 6 Mines are <br />located between the Trout Creek Sandstone and the Middle Sandstone. <br />Middle Sandstone: Under TC, Middle Sandstone well TR -7A is measured for water level and field <br />parameters on an annual basis, with no water quality analyses required. Field parameter data for TR -7A, <br />suggests no adverse impact or trend. 2014 field parameters are provided on Table 5. A historical summary of <br />the Period of record (POR) water quality data is provided on Table 6. POR water levels and conductivity <br />readings are presented in Figures 3 and 4, respectively. Historically, well TR -7A has indicated a slight <br />reduction in concentrations of major ions over time. <br />3.1.2 Mine Water Discharge <br />Following approval of the TC Monitoring Plan, meter readings were no longer recorded for the 7 North <br />Angle (7NA) site (CDPS Outfall 024, a.k.a. site 9P3). Tables 7 and 8 show well level data for 7NA well and <br />water quality data for site 9P3, respectively. This is a mine dewatering well site that would eventually <br />discharge into the Williams Fork River. The Eagle No. 5 Mine sump discharge is CDPS Outfall 003, a.k.a. <br />site 5D (Table 9). It is also a mine dewatering pump. Under TC, monitoring of these sites remains the same <br />as in the active mining monitoring plan, however 9P3 has not discharge since 2001, and no near future <br />discharge is anticipated. Site 5D has not discharged since June 2013, when power was removed from the site. <br />No near future discharge is anticipated from this site either. Please consult prior AHRs for historical data. <br />3.1.3 ALLUVIAL WELLS <br />Under TC, water data in the Williams Fork River Alluvium is monitored via alluvial well AVF-5, which is <br />located adjacent to the underground discharge sediment ponds area (See Figure 2). Under TC, AVF-5 is <br />measured for water level and field parameters on an annual basis (between July 20th and August 30th) <br />concurrent with the Williams Fork surface water sampling (site WF -1). No water quality analyses are <br />C-81-044 2015 AHR <br />