2014-04-09_PERMIT FILE - M2014001 (4)

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were eroded, and the process of cutting and filling of channels was so widespread that gravel and sand were deposited in sheet -like beds. The principal streams eroded into the bedrock, cutting and building terraces along the channels. More recent streams, such as Lone Tree Creek in the proposed permit area, have cut through the highly erodible over -lying unconsolidated material in most areas and do not generally have associated alluvial deposition. Traditional organic topsoil on most of the site is thin or non - existent, ranging from 0 to 6 inches thick. Most of the soils are shallow to deep loams that are well drained. Over most of the identified sand and gravel deposit is a loamy, wind -mixed veneer layer of soil overburden material varying in depth from 0 to 6 feet. The soil overburden material likely developed from alluvial and eolian deposits of clay, silts, and sands. Over time, erosive forces of wind and water have influenced the soils on the site. Mobile soil particles, such as silt and clay, have eroded from higher topographic positions and have been re- deposited in lower areas. Therefore, swale areas may have finer textured soils than ridgetops. The aggregate deposits and loamy soil overburden material are underlain by a variable pattern of shale and sandstone parent materials. Mine Phasing Connell Resources anticipates mining and reclaiming the proposed Connell Carr Pit site in approximately 15 years. However, the rate of mining and overall life of the mine is dependent on several factors including product demand. Test pits have verified that commercial deposits of sand and gravel exist up to 25 feet below the surface of the ground. In addition to the commercial sand and gravel materials, clay, silt, and other non - marketable materials excavated from the proposed permit area will be used on -site for reclamation. The mining plan currently includes mining in two phases; the first phase south of Lone Tree Creek and the second phase north of the creek (see Exhibit C -5, Pre- Mining/Mining Plan Map). Phase I (288 acres) will be mined from the northwest to the southeast. When Phase I is complete, a temporary crossing will be established through the Lone Tree Creek drainage and Phase II (94 acres) will be mined from east to west. All necessary permits will be obtained and any special construction techniques will be used to reduce impacts and create a stable crossing through the ephemeral drainage. Mining will not occur within the Lone Tree Creek channel. Even though the proposed permit area will be mined in only two phases, integration of mining and reclamation is still applicable. In general, as the pit reaches its maximum depth and edges are completed, they will be backfilled and reclaimed. In areas where the final pit depth has been achieved and operations are no longer present, backfilling and reclamation of pit walls will extend onto the floor. Rough contouring of the pit floor with the Lone Tree Creek drainage will take place during mining while fine contouring and establishing final drainage patterns will be one of the last steps in the reclamation process. The contour blending will avoid steep transitions and create a topography that produces a smooth, relatively low velocity flow from the mined area to the adjacent creek drainage system. Overland flow patterns will be incorporated into this transition so as to connect the pit floor with existing shallow drainage swales. Connell Carr Pit DRMS 112 Permit Application Adequacy Review Response