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ENVIRONMENT, INC. PAGE 2 <br />NOVEMBER 27, 201 2 <br />Figure AD -2 is a cross section sketch showing the information you <br />request. <br />3. The Applicant has stated that reject sand will pumped back into the pits. Please clarify if there will <br />be a single discharge point for each of the pits where the reject sand will be pumped or if the sand <br />will be pumped around the perimeter of the pits. If the reject sand will be pumped at a single point, <br />then specify the location. The Division recommends that reject sand be pumped into the pits as <br />far away from any permanent man -made structures as possible, in order to increase the distance <br />between blasting and said structures. <br />I have discussed this with Darren Gebhart and he says the reject <br />sand will be placed along sides of the area being mined at any <br />one time. Typically the mined material is separated from the <br />water at the pivot point so the water and reject sand is returned <br />to the lake. The pivot point is usually located near the dredge <br />due to the limited length of the pipe from the dredge boat to the <br />land. This will generally be along the west and north sides of <br />the lakes. As suggested they will avoid placing the reject sand <br />close to permanent man -made structures as possible. <br />4. The Applicant has stated a 25' setback from the permit boundary will be maintained. In addition, <br />the Applicant has stated that the mining line will be maintained at a distance of 75' inside of the 25' <br />setback. Please commit to marking both the 25' setback and the mining line in the field. <br />I think you misunderstand the intended use of the 75 foot buffer. <br />While it is a setback from the 25 foot mining setback line its <br />intended use it to leave room to assess the working face slope as <br />mining approaches the 25 foot digline or top of slope line. Once <br />the 75 foot buffer line is reached McAtee would determine what <br />gradient the underwater mining slopes are at that time. If they <br />are 2.5:1 then mining would slowly approach the setback line <br />leaving enough material to complete final sloping to 3:1. <br />According to my calculations, if the mining slope is 2.5:1 then <br />one would need approximately 2.08 cy /lft of material to complete <br />the 3:1 slopes. To leave adequate cut /fill material the top of <br />mining slope would stop at 4.5 feet from the 25 foot top of <br />slope. This will leave 2.45 yd /lft usable material for creating <br />the 3:1 slope. McAtee will commit to establishing and maintain- <br />ing the 25 foot setback line, the 4.5 foot mining limit line and <br />the 75 foot buffer line as mining approaches the permit bound- <br />aries. <br />6.4.5 Exhibit E - Reclamation Plan <br />5. The Applicant has stated that it may be necessary to cut/fill the pit walls to achieve the final grade <br />of 3H: 1V for five feet above and ten feet below the static water level. Please clarify how the final <br />grade would be achieved if the Operator does not cut/fill the pit walls. <br />The only method we know of to construct the final slope at 3:1 is <br />to use a cut /fill method. It is entirely possible that when it <br />comes time to grade the final slopes, that wave action may have <br />caused the loose material to slough off leaving an underwater <br />slope equal to or less then the required 3:1 rate. We will have <br />to measure the final mined slope to know if any grading will be <br />needed to establish the final slope. <br />