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Sneffels Creek, where it then mixes and flows down the valley to the Uncompaghre River. In <br />addition to the Revenue Mine, the Atlas Mine immediately upstream of the main Revenue area also <br />discharges into Sneffels Creek. Surface water samples have been taken at upstream on Sneffels <br />Creek (SW -2), downstream points on Sneffels Creek (SW -4), the Atlas discharge (SW -1), and the <br />Revenue seep (SW -3). Ground water samples have been taken within the Revenue mine starting <br />from just inby the Atlas Drift (UG -4), a sample of the Atlas Drift (UG -3), where its water joins with <br />the Revenue mine water, the mine water inby the Yellow Rose Drift (UG -2), and the Yellow Rose <br />Drift itself (UG -1). All of the locations for the underground and surface sample points are shown <br />on Map G -1. Overall, the water quality emanating from the mine is good; pH is approximately 7.9- <br />8.3 and the water is relatively free of heavy metals. Additional discussion of the surface and ground <br />water regimes are discussed in Exhibit G. <br />Since zinc is the main ion of concern, the following discussion of water quality is based on zinc. <br />A partial suite of water samples at the above points were taken in the 4 quarter of 2011 (with the <br />exception of the Atlas Drift UG -3 and the Revenue Tunnel inby Atlas Drift UG -4). Full sample <br />suites were conducted in the Q1 2012, Q2 2012, and Q3 2012 for a full year of water data for the <br />Revenue Mine. For the surface water samples, dissolved and total ions were measured. For the <br />underground samples, only dissolved ions were tested. These recent water quality test results are <br />enclosed in Appendix 4. <br />Figures T -1, T -2, T -3, and T -4 show how these different points of water flow interact and Table T -1 <br />shows the flows, concentrations of zinc, and the calculated mass flow balance of zinc for this <br />system. The mass flow rate at each sample point is calculated from the measured flow and the lab <br />results for concentration of dissolved and total zinc. <br />Based on the mass flow balance calculations shown in Table T -1 for Q4 2011, it was determined <br />that the Sneffels Downstream values (63.59 g/hr) did not reflect the known contributions of zinc <br />added together (Atlas Discharge + Upstream Sneffels + Revenue Seep = 95.62 g/ hr). It was off by <br />-33 %. Q1 2012 cannot be effectively analyzed regarding surface water flows, since the Atlas <br />Discharge did not have a surface flow due to the harsh winter conditions, therefore, it was not <br />Revenue Mine August 2012 T -2 <br />