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Received ~ ~ <br />MAY 2 5 2000 <br />Durango Field Office EXHIBIT D: Mining Plan <br />Division of Minerals 8 Geology AGRI -DLD Gravel Pit <br />The AGRI-DLD gravel pit, consisting of a staging area, 7 mining phases, sediment ponds and <br />two access roads, is 76.27 acres, with 46.39 acres affected by mining. The site is located in <br />La Plata County, near industrial/ commercial uses. The phases progress in a roughly north, <br />north-easterly fashion in 4 to 9 acre increments and will be mined in the order they are <br />numbered on the mining plan map (Exhibit C). Phase 7 is to the south and will be mined last. <br />Each phase will take approximately 5 years to mine, giving the mine an expected life of 35 <br />years. Mining is expected to commence in the Spring/Summer of 2000, and finish in the Fall <br />of 2035. <br />Mining operations <br />The mining of the AGRI-DLD gravel pit is a surface mining operation. A bulldozer will be <br />used to collect the topsoil and overburden. The topsoil depth, ranging from 0-6 inches, will be <br />stored on site and seeded to prevent erosion and weed infestation. The overburden is <br />estimated to be 0-6 feet deep and will be used to recreate 3:1 slopes around the edge of the pit <br />boundary. The gravel deposit is estimated to be up to 20 feet deep and will be mined and <br />processed on site with crushers and a wash plant. Front loaders will be used to fill a crusher <br />that produces aggregate product for construction. The wash plant will be located in the <br />staging area. The water used in the wash processing will be hauled in. The water used for <br />processing will be channeled into a series of two sedimentation ponds where sediments will <br />be settled out. Whenever possible, the water will be recycled and used again for gravel <br />washing purposes. Runoff water will be contained in areas that daylight to natural slopes by <br />maintaining a 3' high by 15' wide berm in place or constructed in those areas and directed to <br />detention ponds. <br />Manmade structure avoidance <br />In order to avoid damaging the pipelines and electrical transmission line running through the <br />southern portion of the pit boundary, the operator plans to stay 90 feet from either side of the <br />right of way (R.O.W.). The 90-foot buffer was calculated by multiplying the maximum high- <br />wall depth of 30 feet by 3, thus ensuring a 3:1 slope even in the event of slope slough. The <br />only area where gravel deposits will be mined south of the pipeline R.O.W. is phase 7. On this <br />southern side of the R.O.W. the 90-foot buffer will be increased to 100'. (Please see mining <br />plan map.) A road under LPEA's power line will be constructed from the Phase 1 area to the <br />Phase 7 area. In order to avoid damage to LPEA's property, AGRI- DLD, LLC. has agreed to <br />meet LPEA's requirements for road construction (see attached). <br />There are fences running along the western, northern, and southern property lines. In order to <br />avoid damaging the fences, mining activities will come no closer than 90 feet to the fence <br />(and/or property line). The 90-foot buffer was calculated in the same manner as above - by <br />multiplying the maximum high-wall depth of 30 feet by three, thus ensuring a stable 3: I slope. <br />This 30-foot high-wall will also be reclaimed to a 3:1 (or less steep) slope. <br />Drainage plan <br />Runoff occurring during or after mining operations will be channeled to sediment catchment <br />or detention ponds. One pond will be located in the east-central portion of the pit. The other <br />catchment pond series is mentioned above as part of the wash plant wastewater treatment <br />plan. For phase 7, a separate detention pond will be placed to handle runoff. Please see next <br />page for pond detail. <br />