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bedrock groundwater points of compliance are unwarranted at the Seneca IIW Mine. Six <br /> surface water sites are monitored within the Hubberson Gulch drainage. Water quality <br /> samples are obtained semiannually for the parameters listed in Appendix 15-3A. <br /> Waters used for irrigation include areas downstream of monitoring sites WSHFFI,WSD5, and <br /> WSSF3. Manganese standards were occasionally exceed and water quality concentrations <br /> remain within the CDPHE receiving stream standards at each monitoring site with the <br /> exception of iron and TDS excursions most likely due to runoff events in spring carrying a <br /> high level of suspended solids. TDS concentrations remained within the PHC predictions for <br /> the site. The PHC predicts an irrigation season average TDS value of 2193 mg/l for this <br /> site. <br /> Dry Creek <br /> Two surface sites are monitored within the Dry Creek drainage, downstream of mining <br /> (WSD5 and Pond 5). The surface water quality concentrations remain within the historical <br /> range as well as within the PHC predictions displaying a statistically significant,increasing <br /> TDS trend. <br /> Sage Creek <br /> SPL monitors three surface water sites in the Sage Creek drainage. The surface water quality <br /> concentrations remain within the CDPHE agricultural use standard range as well as within the <br /> PHC predictions displaying a statistically significant,increasing TDS trend. <br /> Springs and Seeps <br /> An initial spring survey in July, 1979, located 49 springs and seeps in and near the <br /> permit area. Two additional springs were identified during the 1997 baseline studies for <br /> the IIW South Extension Area. The majority of the springs and seeps occur in valley <br /> bottoms. The recharge to valley bottom springs may be from a discontinuous alluvial <br /> aquifer, from colluvial slumps, or from perched aquifers draining to stream sediments. <br /> Several springs issue from the Williams Fork Formation, while others issue from the <br /> overlying Twenty Mile Sandstone. Some springs are utilized to fill stock ponds in the <br /> area, while the majority either contribute to streamflow or provide recharge to <br /> downgradient alluvium. Olson Spring, an adjudicated domestic water right, issues from <br /> the Dry Creek Alluvium about 20 feet from Dry Creek. Currently,nine springs are <br /> monitored at the site,comprising five spoil springs and four native springs. <br /> The CDPHE water quality use and receiving stream standards appropriate for the site are: <br /> o Surface water agricultural use standards <br /> o CDPHE,Regulation 31,2009 <br /> o Yampa Segment 13d,Regulation No 33,2015 <br /> No ammonia excursion occurred and all test values for mercury and sulfide were less than <br /> the MDL. <br /> Native Springs <br /> Four native springs are monitored and discharge flow at the springs remains within historical <br /> range. Water quality concentrations are within the CDPHE agricultural use standard except <br /> for occasional annual manganese and iron excursions. TDS concentrations are with <br /> historical range and show a statistically significant increasing trend. <br /> Spoil Springs <br /> Five spoil springs are monitored and discharge flow at the springs remains within historical <br /> Page 22 of 37 <br />