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6. Groundwater point of compliance: TDS measured at DCAL-02, in the Dry Creek alluvium was well below the compliance standard of 3,195 mg/l. <br /> <br />7. Springs: Flow was higher than average at all of the monitored springs. TDS <br />shows an increasing trend at all of the springs except the spring (S50) near the damaged wells at Pond 016, the Smith water supply on Hubberson Gulch (S7), and the spoils spring (S5) near drainage PM-2 above Pond 016. Water quality in <br />all of the springs is consistent with irrigation standards. <br /> <br />7. Surface water flows were above average at all monitoring locations, again this is due to exceptionally high snowpack and heavy spring precipitation of 2011. <br />8. Surface water quality: Receiving stream standards were exceeded on some <br />occasions, as outlined in SCC’s report. <br /> a. Iron limits were exceeded on seven occasions, mostly during spring runoff. SCC notes that premining iron levels were generally in excess of <br />the standards for iron, and that the standards have since been revised <br />based on ambient conditions prior to mining, so it is likely that future <br />monitoring of average conditions will be in compliance with receiving stream standards for iron. <br />b. Mercury limits were exceeded one time on the downstream Sage Creek <br />site. SCC believes this to be an anomaly, which is likely, based on prior <br />monitoring data at this site. c. Selenium was in excess of the receiving stream standard on five <br />occasions at pond outfalls. Four of the excursions were at Pond 017, and <br />SCC reports that they are currently on a Compliance Schedule with <br />CDPHE to meet the selenium limit by December 31, 2015. The other exceedance, at Pond 016, is discussed below. <br />9. TDS values at stream monitoring locations show a generally increasing trend. <br />On Hubberson Gulch and Dry Creek, TDS values are below predicted values. <br />On Sage Creek, TDS averages 940 mg/l, which is above the predicted value of 676 mg/l. SCC notes that the maximum TDS level in the two outfalls discharging to Sage Creek was 480 mg/l. There are no spoil springs draining to Sage Creek <br />and very little disturbed area contributes to the watershed, so it would not appear <br />that this increase is due to mine-related influences. <br /> 10. One NPDES effluent limit was exceeded in 2011; selenium was reported at 4.8 ug/l (limit is 4.6 ug/l), but SCC notes that total recoverable selenium was <br />analyzed at 3.9 ug/l. SCC further contends that their CDPS permit states that <br />this standard is “not to be exceeded more than once every three years on the <br />average” and the data show that the standard has not been exceeded in the six years prior to this excursion or since then.