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HYDROLOGIC SYSTEM <br />Drainage Control: Is managed through a series of diversions for both <br />disturbed and undisturbed area through a series of channels, culverts, <br />drop structures and two sediment ponds. <br />Diversions: There are two undisturbed area diversions around the <br />perimeter of the disturbed area. The major channel located on the <br />eastern side of the mine was snow covered so it was not readily apparent <br />that it was totally functional but there were no major obstructions <br />noted in the visible portion of the diversion. The western perimeter <br />undisturbed area diversion was walked. No problems noted. <br />Runoff from the major portions of the surface of the disturbed area <br />is diverted underground through a series of cmp pipes and drop <br />structures. All of the entrances and exits of the pipes or drop <br />structures were checked and found to be clear. Were ever possible, pipes <br />were checked for obstructions or collapse. As far as I know all were <br />clear and functional. <br />Impoundments: There are none on the mine. <br />Siltation Structures: There are two sediment ponds. There was no <br />standing water nor was there a discharge. There was evidence of the <br />operator having recently cleaning the eastern pond. Both ponds were <br />found to be functional but there was a problem noted with the design as <br />constructed. Both ponds have a single piped outlet through the <br />embankment. Colorado's regulations do not allow this unless there is <br />total containment for a 25 yr 29 hr storm with a provision for some type <br />of mechanical drawdown. <br />Mr. Ranney explained that the operator had approval for the design to <br />install two separate spillways in each of the ponds but due to changes <br />in other recent and ongoing design calculations for other drainages on <br />the mine, they have not constructed them to date. Mr. Ranney explained <br />that he was reviewing the final calculations and design work for the <br />change. They are to be approved as this report is being prepared. It <br />was the decision of this office to forego enforcement action normally <br />issued for this type of violation because of circumstances and approvals <br />as noted. <br />Discharge Structures: Both pipes were open and appeared to be functional <br />in the embankments of the ponds. <br />Surface Water: The operator does not monitor surface water other than <br />record discharges from the sediment ponds should it occur. <br />Ground Water: Since there were no records, I am aware that the operator <br />monitors a ground water well used for mine water but that was not <br />