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and flows down the valley to the Uncompaghre River. In addition to the Revenue Mine, the Atlas <br />Mine immediately upstream of the main Revenue area also discharges into Sneffels Creek. Surface <br />water samples have been taken at upstream on Sneffels Creek (SW -2), downstream points on <br />Sneffels Creek (SW -4), the Atlas discharge (SW -1), and the Revenue seep (SW -3). Ground water <br />samples have been taken within the Revenue mine starting from just inby the Atlas Drift (UG -4), a <br />sample of the Atlas Drift (UG -3), where its water joins with the Revenue mine water, the mine <br />water inby the Yellow Rose Drift (UG -2), and the Yellow Rose Drift itself (UG -1). All of the <br />locations for the underground and surface sample points are shown on Map G -1. Overall, the water <br />quality emanating from the mine is good; pH is approximately 7.9 -8.3 and the water is relatively <br />free of heavy metals. Additional discussion of the surface and ground water regimes are discussed <br />in Exhibit G. <br />Since zinc is the main ion of concern, the following discussion of water quality is based on zinc. <br />A full suite of water samples at the above points were taken in the 4th quarter of 2011 (with the <br />exception of the Atlas Drift UG -3 and the Revenue Tunnel inby Atlas Drift UG -4). Another full <br />suite of tests were conducted in the 1 quarter of 2012. For the surface water samples, dissolved and <br />total ions were measured. For the underground samples, only dissolved ions were tested. These <br />recent water quality test results are enclosed in Appendix 4. <br />Figures T -1 and T -2 show how these different points of water flow interact, and Table T -1 shows <br />the flows, concentrations of zinc, and the calculated mass flow balance of zinc for this system. The <br />mass flow rate at each sample point is calculated from the measured flow and the lab results for <br />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 (4.44 g/hr) did not reflect the known contributions of zinc <br />added together (Atlas Discharge + Upstream Sneffels + Revenue Seep = 6.67 g/ hr). This shows <br />that somewhere along the system, zinc is dropping out of the surface water. Q1 2012 cannot be <br />effectively analyzed regarding surface water flows, since the Atlas Discharge did not have a surface <br />flow due to the harsh winter conditions, therefore, it was not sampled, but it is believed that <br />Revenue Mine August 2012 T - <br />