Laserfiche WebLink
---------------------------------- <br />Outfall/Sediment: .......... <br />Pond <br />12 <br />------------------ -------------------------- <br />j Sediment <br />Loss <br />Pre -Mining <br />TSS_ <br />DMRs <br />----- --------- <br />------ mg/I----------------- <br />Mg/I ---------- <br />00510,043.00 <br />Sediment Pond <br />70 <br />006a <br />6029.00 <br />37 <br />007a ----------------- <br />10,854.00___ <br />No_Discharge <br />008 <br />7,246.00 <br />69 <br />009 (Outfall 030)9,625.00 <br />---- ---------11------------------ <br />-------------------------- <br />237 <br />009a (Outfall 031) i <br />- --------------------------- <br />1,655.00 <br />No Discharge <br />Column_ 1- SedCad calculated_TSS_ value, pre -mining ........................ <br />009a (Outfall 031) <br />Column_2_- Actual discharge <br />data as reported in DMRs <br />-------------------------- <br />from 2008-2015 <br />* Values listed are acute exceedences, permitted value is 45m /1 <br />The second method of comparison is based on average annual sediment loss as <br />calculated by a RUSLE demonstration in Excel. It is important to note, the RUSLE <br />demonstration does not take into account that a sediment pond is in place. With a <br />sediment pond in place, the sediment lost is significantly lower than calculated due to the <br />function and operation of each sediment pond. <br />Results from the demonstration are summarized below. <br />SUMMARY OF RUSLE RESULTS <br />Pre -Mining <br />Reclaimed <br />Outfall/ <br />Sediment Loss <br />Sediment Loss <br />Sediment Pond <br />Tons/Acre/Year <br />Tons/Acre/Year <br />00512.60 <br />....................................................................................................... _......................................................................................................... <br />1.46 <br />006a10.92 <br />............................................................................................................................................................................................................._ <br />11.20* <br />007a9.24 <br />.............................................................................................................................................................................................................. <br />5.04 <br />00811.60 <br />.................................................................................._................................................................. <br />. ................................. <br />5.88 <br />009 (Outfall 030.)....................................................................10..08................................. <br />3.08 <br />009a (Outfall 031) <br />26.04 <br />2.00 <br />* Negligible difference, 0.28 tons/acre/year which amounts to .025% of the annual sediment lost. With a <br />pond in place, sediment loss is greatly reduced. <br />In conclusion, implementation of the Sediment Control Plan (sediment ponds, in-place) <br />will result in average annual sediment yields that will not be greater than the sediment <br />yield levels from pre -mined, undisturbed conditions. <br />Subpart H Demonstration Page 3 03/15 <br />