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sediment report. I would contend the output generated and displayed in Table 2 (January 13, <br />2016) is more of a temporal sediment demonstration than a spatial sediment demonstration <br />between reclaimed and non -mined land. The RUSLE model variables R, K, LS, and P are <br />identical and the averaged cover values are only 4% different between reclaimed and non -mined <br />lands with standard errors for total cover of 2 or greater. Precision of cover data was I%, so one <br />should not have used cover values as input with tenths or hundredths of percent, which gave the <br />RUSLE model a premise of a precise and accurate model. <br />The majority of runoff water and an unknown amount of sediment that are contributing to the <br />problem of erosion and sediment deposition north of the permit boundary is an issue of concern <br />since bond release is based on problems within the permit boundary. Mr. Jack Robeda discussed <br />on November 11, 2015 his concerns and the concerns of the Warnock's who own the property <br />north of the green gate and adjacent the Corley property. This was my concern also, that the <br />amount of sediment leaving the permit boundary, and then the Corley property could be in <br />violation to standards of the Clean Water Act or state or national soil loss tolerance levels. The <br />cause or a major contributing portion of this impact is within the permit boundary and since this <br />area is within the permit boundary then this is an issue that needs to be resolved. Additional <br />RUSLE model demonstrations will not resolve the problem. <br />The second objective stated in the sediment report is to demonstrate that the reclaimed area does <br />not contribute excess suspended solids to streamflow as compared to a non -mined area. <br />According to the letter dated December 31, 2015, EFCI's response states actual water samples <br />are never submitted to demonstrate sediment yields. Therefore, the use of only RUSLE model <br />output fails to demonstrate any value of suspended solids in water that may be transported to a <br />stream or within stream flow. The RUSLE model does not predict runoff volumes so predicting <br />suspended solids in water must be accomplished by other methods not described in the sediment <br />report. Again, the statements claiming demonstration that the reclaimed lands produce less <br />annual erosion or does not contribute excess suspended solids to streamflow compared to non - <br />mined lands was not demonstrated with the sediment report nor the Addendum. <br />Prior to 2011, I observed on two occasions where Mr. George Patterson hired earthwork <br />contractors to clean sediment from Pond 5 and to remove sediment from the downstream end of <br />two culverts that drain under the County Road 92 at the south end of Pond 5. During these two <br />times, sediment from within these culverts were also cleaned out. In addition, the upstream end <br />of these culverts (located in the west road ditch) were also required to be cleaned out at least <br />once. Some armoring of this channel also occurred during this time (over the past 5 years). <br />Before these two clean-out/removal occasions occurred, Pond 5 runoff catchment and sediment <br />retention ability may have been reduced because the upstream end of these two culverts may <br />have been partially or completely blocked. <br />As sediment fills the culverts going into Pond 5, the water flow and sediment contained in the <br />runoff water that is expected to enter Pond 5 and retained within the permit boundary is then <br />instead directed down the west road ditch. This amount of water and sediment yield is variable <br />because it is based on the number of culverts completely blocked or the percentage of partial <br />blockage. When these two culverts are complete blocked, Pond 5 has no hydrologic function for <br />water or sediment contained in the west road ditch. I have not yet observed this at the site. <br />