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Surface Water Control and Containment for Ore Bins and Loading Area <br />Surface water runoff within the berm around the staging area will flow to the northeast to <br />the retention pond as described in the following paragraph and illustrated on Map C-2(b) <br />and Photograph 9. Only the area above the Ore Bins and Loading Area can impact the <br />Ore Bin Berm, and it will be diverted around the bins. The berm around the Ore Bins and <br />Loading Area (OBLA) is designed for total containment for any precipitation that falls <br />within the area. <br />This OBLA was determined to be approximately 3,400 square feet. The worst case <br />scenario would be that all of the water that falls on the area from a 2-year 24-hour storm <br />plus 10-year 24-hour storm event would require containment. The total for both storms <br />would be 907 cubic feet or 6,782 gallons (based on 3.2 inches of rainfall, NOAA ATLAS <br />2, Volume III, Figures 26 and 28). Depending upon subsurface investigation, this pond <br />may be lined, but will more likely be a prefabricated storage vessel of adequate size. A <br />retention pond would be designed to contain the entire volume of run-off from a 2-year <br />24-hour storm plus 10-year 24-hour storm event while maintaining at least 0.5 ft of <br />freeboard. <br />Certification Statement <br />By means of this Professional Engineer Certification, I herby attest to the following: <br />I have reviewed the information provided in the plan and the design as described <br />above; and I have determined that the design will provide full containment of <br />surface water run-off from the Ore Bins and Loading Area affected by the <br />Monogram mining operation. <br />Thomas J. Jaan _ <br />Printed Name of Registered Professional Engineer <br />L <br />Signature of Reg' ter Professional Engineer <br />Date: March 9, 2009 Registration No.: 1837 State: Wyoming