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Liberty Mining, LLC <br />DBMS 110 -d Permit Application <br />October 2013 <br />Table U (10 -4) <br />Peak Runoff Pond Volume Required <br />Resulting from <br />100 - Year /24 -Hour Rainfall Event <br />For Operational Site <br />Pond <br />No. <br />Drainage <br />Area, <br />Ac <br />Time of <br />Con. <br />Hr <br />Weighted <br />CN <br />Unit Peak <br />Discharge <br />cfs /ac -in <br />24 -Hour <br />Rainfall <br />Depth, in <br />Direct <br />Runoff, <br />in <br />Peak <br />Discharge, <br />cfs <br />Runoff Volume <br />Ac -Ft /Cu Ft <br />1 <br />9.18 <br />0.33 <br />25 <br />1.33 <br />3.0 <br />0.33 <br />4.03 <br />0.25/10,957 <br />2 <br />0.33 <br />0.19 <br />85 <br />1.80 <br />3.0 <br />1.60 <br />0.95 <br />0.0261/1135 <br />3* <br />0.276 +0.19 <br />0.19 <br />85 <br />1.80 <br />3.0 <br />1.60 <br />0.95 +0.20 <br />0.0447/1940 <br />4 <br />0.234 <br />0.16 <br />85 <br />1.80 <br />3.0 <br />1.60 <br />0.67 <br />0.013/570 <br />5 <br />9.18 <br />0.33 <br />25 <br />1.33 <br />3.0 <br />0.33 <br />4.03 <br />0.25/10,957 <br />*(Note- Because Drainage Basin #4 is the entrance to the mine and all flows from the basin flow <br />toward the mine entrance, it was assumed that the drainage water would be pumped to the <br />closest pond, Pond #3 for disposal. Basin #4 flows are therefore added to the Basin #2 flows to <br />become the total flows into Pond #3.) <br />Table U (10 -5) <br />Pond Volumes for <br />100- Year /24 -Hour Rainfall Event <br />For Operational Site <br />Pond <br />Runoff Volume <br />Runoff Volume <br />Excess <br />Excess <br />No. <br />Req'd to Contain <br />Created by Design <br />Volume <br />Volume as <br />100 -Yr Storm <br />Event, <br />Available, <br />a % of <br />Event, Cu Ft <br />Cu Ft <br />Cu Ft <br />Req'd <br />Volume <br />1 <br />10,957 <br />13,276 <br />2,319 <br />21.1 % <br />2 <br />1,135 <br />1,392 <br />257 <br />22.6% <br />3 <br />1,940 <br />2,102 <br />162 <br />835% <br />4 <br />570 <br />617 <br />47 <br />8.2% <br />5 <br />10,957 <br />12,034 <br />1,077 <br />9.8% <br />U (11 -12) Surface Water Quality Data <br />There are no continuous flowing streams, ponds, lakes or other bodies of water within 1.5 miles <br />of the mining site. Nearby seeps, spring and livestock ponds are geologically and <br />topographically up gradient of the Liberty Mine site. Surface water is scarce in the area of the <br />mining operation. A Colorado Stormwater Management Plan is to be prepared, based on the <br />surface and stormwater control plan found in Section U(10) of this permit. <br />Liberty Mining, LLC Moab, Utah SMA Ref. 5821697 Page 64 <br />