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Mr. Jack Henris <br />November 2, 2016 <br />Page 2 <br />m:\min\tc1\_teller\m-1980-244 cc-v\tr-82 sgvlf phase 2 defermnt\m-80-244-tr82par2016-11-02.docx <br />2) Page 2, Storm water controls. Specific to Comment #1 above, this paragraph states <br />“Newmont will commit to operational maintenance of the check dams in ensuring they <br />function as designed.” Please change/confirm this is a CC&V commitment. <br />3) Figure 1. Proposed surface roughening and Note 5. According to the figure and Note 5 <br />(and further explained in Detail C, Figure 2), a 100-foot wide strip of the Phase II subgrade <br />upgradient and adjacent to the haul road will be roughened, presumably for assistance in <br />erosion control. As the upgradient slope length is generally between 800 and 1,200 feet, <br />the Division is uncertain as to how effective this roughening will be. Please provide <br />rationale as to why this surface roughening is only to be applied to the last 100 feet above <br />the haul road V-ditch. <br />4) Figure 2. Note 3 and Detail B. <br />a. Note 3 indicates the roadside V-ditch is designed to convey the runoff from the 5- <br />year, 24-hour storm. Runoff collected by the roadside ditch is conveyed to the <br />Phase I sediment pond (a.k.a. EMP 008c) which is designed to store two times the <br />10-year, 24-hour storm runoff volume (ref. Note 6, Figure 1). As such, it would <br />appear more appropriate that the roadside V-ditch have the capacity to convey the <br />10-year, 24-hour peak flow. Please provide the Division with adequate rationale <br />for designing the roadside ditch with a conveyance capacity less than the 10-year <br />runoff for which the downgradient sediment pond is designed. <br />b. Detail B shows an undefined height of slope to be 1H:1V adjacent to the roadside <br />ditch. Is this 1H:1V slope to be roughened as shown in Detail C? <br />c. Detail B also shows a two percent backslope on the haul road towards the roadside <br />V-ditch. How will this reverse gradient be corrected during Phase II construction <br />in order to prevent pregnant solution from ponding here above the double-lined <br />(not triple lined as in the PSSA) portion of the VLF? <br />5) Figure 3. Details G and H. Both these details show the Phase II secondary underdrain <br />daylighting into the roadside V-ditch, presumably to convey underdrain flows to the Phase <br />I sediment pond. The details also show a three-foot clay plug in the Phase I secondary <br />underdrain. <br />a. How much water is expected to be diverted from the Phase II underdrains to the <br />Phase I sediment pond and how much of the design volume for the Phase I <br />sediment pond (two times the 10-year, 24-hour runoff volume) will that underdrain <br />flow displace? <br />b. Please confirm the Phase II underdrains will be reconnected to the Phase I <br />underdrains prior to starting the Phase II liner construction. How will the clay <br />plugs be removed and the underdrains reconnected? Will these connections be <br />certified as functional during the Phase II construction quality assurance program?