2018-10-11_PERMIT FILE - M2018053

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EXHIBIT D MINING PLAN 1. General Mining Plan Pre-Law mining (prior to 1980) occurred on approximately 240 acres of the combined Derry Ranch and Box Creek site, herein referred to as Box Creek Placer, since the 1890s in the areas shown as `mine tailings' on Map C-1. These areas are included within the permit area. Various digging, hydraulicking, sluicing and other methods were employed during historic mining of the Box Placer site.No topsoil was salvaged from past operations and no final grading was completed. Future mining will occur throughout the site in areas marked on Map C-2 Mine Plan. Proposed Exploration Areas, see Map C-2, will be potentially mined based on exploration results. Map F-I shows the Reclamation plan. The site and surrounding area is generally composed of fluvial terraces that slope gently eastward from the foot of the Sawatch Range towards the Arkansas River. Lake Creek and the Twin Lakes divide the deposit in to two principle economic areas: the Derry Ranch placer to the north and the Cache Creek placer to the south. The Twin Lakes are surrounded on their northern, eastern and southern sides by moraine laden hills. East-flowing creeks incised these terraces resulting in the two principle placers that align with creek flows and result in long broad valleys. Bull Lake glaciation (200,000— 130,000 years ago) outwash sediments are found throughout and surrounding Box and Corske Creeks. The head and sides of Box and Corske Creeks are floored with younger outwash gravels while the terraces to the north and south of each creek are composed of older Bull Lake outwash sediments. The valley floor is composed of deposited alluvium, the site of the majority of historic stream gravel placering. To the east, the valley slopes gently to the Arkansas River and merges with Pinedale glaciation (30,000 -10,000 years ago) outwash surfaces and modern river alluvium. Throughout the Leadville-Twin Lakes valley,the vertical extent of placer material is underlain by `lake beds.' Ben H. Parker, Jr., author of The Geology of the Gold Placers of Colorado,the definitive placer resource for Colorado, defines `lake beds' as clay layers that are>10 feet thick that may be underlain by a series of thinner barren gravel and clay layers. The contact with overlying placerable gravels and the `lake beds' is sharp and easily observable. This clay layer is Box Creek Placer Mine G]eg 1e ickj and As wtm PLL( September 2018 D-1