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ENVIRONMENT, INC. <br />DECEMBER 2, 201 4 <br />PAGE 2 <br />groundwater. Please commit to monitoring groundwater for a minimum of 1.25 years prior to <br />affecting alluvial groundwater. Please commit to making a trigger point any observed or reported <br />off -site impact. <br />We will not commit to that condition. This requirement to delay mining or construction of <br />the slurry wall for 15 months is unreasonable. When the site was drilled in August 2007 <br />the groundwater was measured at 5064 to 5066 in 5 location in Phase 1. In June 2013, <br />two test holes were drilled in Phase 1 and the water elevation was 5062 & 5064. Since <br />the highest elevation was 5066 and the lowest was 5062. 1 propose that we start with <br />these two elevations as the starting points, "until /unless more accurate groundwater <br />elevation highs and lows can be obtained. Our commitment in the groundwater mitiga- <br />tion plan would then be based on these elevations in Phase 1. The slurry wall in Phase <br />t will be delayed until the 'terrace material can be reined allowing for adequate time to <br />collect at least 12 month and 1 quarter of data (13 total). Albert Frei & Sons, Inc. will <br />commit to using any observed or reported off -site impacts to the groundwater table as a <br />trigger point for the mitigation plan. <br />In our phone conversation you mentioned that Frei had committed to collecting a years <br />worth of data. This was intended to be in reference to the CDPHE Certificated of <br />Designation requirements for groundwater quality, not for average depths. While the <br />depths can and will be collected during these sampling events it is a byproduct of <br />collecting a water sample for analysis and was not intended as a primarily groundwater <br />level monitoring plan. The water quality sampling will continue for some time after <br />reclamation is complete as required in a Certificate of Designation. <br />6.4.5 EXHIBIT Z - Reclamation Plan <br />11) Please clarify, will the Operator still use crested <br />wheatgrass to seed the topsoil /growth medium stockpiles. Please <br />provide a seeding rate and method. <br />Albert Frei & Sons, Inc. will commit to using western wheatgrass, and not crested <br />wheatgrass on the topsoil piles if they remain undisturbed for more then one (1) growing <br />season. In the application, a commitment to use 2 pounds of pure live seed ( #PLS) per <br />00 square feet of topsoil pile to be seeded was used. The seed will be broadcast since <br />most topsoil pile ares not accessible by equipment. <br />15) Please clarify, will the inert material be placed into the <br />pit in lifts? If so what will be the average thickness of each <br />lift, and will the lifts be compacted? <br />Two lifts will be used when placing the inert material or the silt material back into the <br />excavated area in Phase 2. On the first lift, from shale to within 10 feet of final surface <br />elevation, material will be dumped at the top of the excavated slope and pushed into the <br />hole using a dozer or a front -end loader. Compaction will occur as filling progresses <br />when the heavy trucks delivering the fill and the equipment used to maintain the site, <br />traverse over it. This compaction is sufficient for the end use purposes. The second lift, <br />final 10 feet of fill, in Phase 2 will be done with well graded inert material and will be <br />compacted so that engineered structures are allowed. <br />