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Erosion Sediment Control
Published in Mritunjoy Sengupta, Environmental Impacts of Mining, 2021
Prior to planting the vegetation, the banks should be graded to a fairly flat slope, preferably 25–33% grade or flatter. Such excavation will destroy any existing vegetation in the bank, but the bank excavation will increase the chemical capacity. The grading should be performed during periods of low precipitation, and the soil exposure time should be minimized.
Construction and Commissioning
Published in S. Can Gülen, Gas Turbine Combined Cycle Power Plants, 2019
Grading is the work of ensuring a level base, or one with a specified slope, for equipment foundations, facility buildings and roads. Graded areas are smooth, compacted, free from irregular surface changes and sloped to drain. Final earth grade adjacent to equipment and buildings are at least 6 in. below the top of finished concrete foundations. Furthermore, they are sloped away from foundations as necessary to maintain positive drainage. Minimum slopes are based on surface type. In general, grades are sloped at a minimum pitch of one-half percent (0.5%) to provide drainage to collection points (1% is even better). Maximum slopes are set based on slope stability, maintainability and the site conditions.
Erosion Sediment Control
Published in M. Sengupta, Environmental Impacts of Mining, 2018
During the preliminary design phase, the mine development plan should be made in a manner that will minimize damage to physical features critical to erosion and sediment control. Grading damage should be minimized as avoiding steep slopes, which result in high cuts and fills, and by following natural ground controls as closely as possible.
Estimation of permeability of soil using easy measured soil parameters: assessing the artificial intelligence-based models
Published in ISH Journal of Hydraulic Engineering, 2021
Balraj Singh, Parveen Sihag, Siraj Muhammed Pandhiani, Sourav Debnath, Saurabh Gautam
Soils are permeable materials due to existence of voids in it, which allow the flow of water from higher to lower energy levels. Permeability is the ability of the material by which it transfers the gases/fluid within the voids. Permeability of soil is a vital engineering property in various soil-related problems like as yield of wells, seepage through dam, cut-off wall and diaphragm wall, seepage through and below the earth structures, etc. Exact knowledge of soil permeability is essential for understand the seepage under dams and other hydraulic structure-related problems. Permeability of soil is influenced by various factors including texture of soil, type of soil, voids ratio, density of soil, and impurities in soil (Harris and Bond 2006). It is also affected by grading curve, level of saturation, soil structure, and soil imperfections or discontinuities (Smith 2014).