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The Q4 2011 samples of Sneffels upstream combined with the Atlas drainage compared to Sneffels <br />downstream showed a drop in zinc, which was expected. The Q1 2012 samples showed an increase, <br />which was a surprise. The mass balance in Table G -4 shows that there must have been another <br />contributor to zinc before the downstream sample location was reached. John Trujillo, the company <br />geologist and mine manager who is in charge of taking the samples, believes that although this sample <br />period showed no flow in the Atlas drainage due to frozen conditions, water was still actually flowing <br />in the stream bed gravel, thus accounting for the extra zinc seen downstream. There are no other <br />visible locations along the permit area where water is entering Sneffels Creek that could be elevating <br />the zinc levels downstream. Also, the Atlas drainage is so high in zinc compared to all other sample <br />points that it would not take much flow there to account for the difference. <br />4.4 Surface Water Systems Designs for Mine Operation <br />Surface water runoff at the Revenue Mine that passes over disturbed areas will be controlled by a <br />series of collection ditches and sediment ponds. This will prevent sediment generated by storm events <br />from leaving the mine site and negatively affecting Sneffels Creek. The stormwater basins, ditch <br />structures, culverts, and sediment ponds can be seen on Map G -1. Table G -6 shows the breakdown of <br />the stormwater flows affecting the site, along with ditch designs information. Table G -7 shows the <br />sediment pond capacity versus the stormwater basin runoff amounts. Diversion ditches will also be <br />used to divert undisturbed runoff from the two mines disturbed areas: the main Revenue disturbance <br />and the Atlas Pile disturbance, which are separated by the Atlas drainage. Appendix 6 contains all of <br />the detailed calculations and designs for all of the stormwater basins (SWB), collection ditches, <br />diversion ditches, culverts, and sediment ponds at Revenue Mine. <br />Stormwater runoff that flows from uphill of the mine will be redirected around the mine disturbance <br />via diversion structures to the existing drainages that feed Sneffels Creek. Map G -1 shows the drainage <br />basins that impact the Revenue Mine, along with the diversion ditches. The biggest drainage from <br />uphill of the Revenue Mine, known as the Atlas Drainage, will be avoided by mining operations. <br />Diversion ditches are all designed to convey the 100 -YR 24 -HR event without generating sediment. <br />The detailed runoff and peak discharge calculations along with the ditch designs were calculated using <br />Carlson and AutoCAD software. <br />Revenue Mine August 2012 G -16 <br />