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Spoil Tip
A spoil tip (also called a boney pile, culm bank, gob pile, waste tip or bing) is a pile built of accumulated ''spoil'' – waste material removed during mining. Spoil tips are not formed of slag, but in some areas, such as England and Wales, they are referred to as slag heaps. In Scotland the word ''bing'' is used. In North American English the term is mine dump or mine waste dump. The term "spoil" is also used to refer to material removed when digging a foundation, tunnel, or other large excavation. Such material may be ordinary soil and rocks (after Coal preparation plant, separation of coal from waste), or may be heavily contaminated with chemical waste, determining how it may be disposed of. Clean spoil may be used for land reclamation. Spoil is distinct from tailings, which is the processed material that remains after the valuable components have been extracted from ore. Etymology The phrase originates from the French word ''espoilelier'', a verb conveying the meanin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canals
Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow under atmospheric pressure, and can be thought of as artificial rivers. In most cases, a canal has a series of dams and locks that create reservoirs of low speed current flow. These reservoirs are referred to as ''slack water levels'', often just called ''levels''. A canal can be called a navigation canal when it parallels a natural river and shares part of the latter's discharges and drainage basin, and leverages its resources by building dams and locks to increase and lengthen its stretches of slack water levels while staying in its valley. A canal can cut across a drainage divide atop a ridge, generally requiring an external water source above the highest elevation. The best-known example of such a canal is the Panama Canal. Many can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weathering
Weathering is the deterioration of rocks, soils and minerals (as well as wood and artificial materials) through contact with water, atmospheric gases, sunlight, and biological organisms. It occurs '' in situ'' (on-site, with little or no movement), and so is distinct from erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity. Weathering processes are either physical or chemical. The former involves the breakdown of rocks and soils through such mechanical effects as heat, water, ice and wind. The latter covers reactions to water, atmospheric gases and biologically produced chemicals with rocks and soils. Water is the principal agent behind both kinds, though atmospheric oxygen and carbon dioxide and the activities of biological organisms are also important. Biological chemical weathering is also called biological weathering. The materials left after the rock breaks down combine with organic material to create so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compounds
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken or new bonds formed or both. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silt
Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension (chemistry), suspension with water. Silt usually has a floury feel when dry, and lacks Plasticity (physics), plasticity when wet. Silt can also be felt by the tongue as granular when placed on the front teeth (even when mixed with clay particles). Silt is a common material, making up 45% of average modern mud. It is found in many river deltas and as wind-deposited accumulations, particularly in central Asia, north China, and North America. It is produced in both very hot climates (through such processes as collisions of quartz grains in dust storms) and very cold climates (through such processes as glacial grinding of quartz grains.) Loess is soil rich in silt which makes up some of the most fertile agricultural land on Earth. However, silt is very vulnerable to erosion, and it has poo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Runoff
Surface runoff (also known as overland flow or terrestrial runoff) is the unconfined flow of water over the ground surface, in contrast to ''channel runoff'' (or ''stream flow''). It occurs when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the soil is #Saturation excess overland flow, saturated by water to its full capacity, and the rain arrives #Infiltration excess overland flow, more quickly than the soil can absorb it. Surface runoff often occurs because wikt:impervious#Adjective, impervious areas (such as roofs and Road surface, pavement) do not allow water to soak into the ground. Furthermore, runoff can occur either through natural or human-made processes. Surface runoff is a major component of the water cycle. It is the primary agent of Soil erosion#Rainfall and runoff, soil erosion by water. The land area producing runoff that drains to a common point is called a drainage basin. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environmental Issues In The United States
Environmental issues in the United States include climate change, energy, species conservation, invasive species, deforestation, mining, nuclear accidents, pesticides, pollution, waste and over-population. Despite taking hundreds of measures, the rate of environmental issues is increasing rapidly instead of reducing. The United States is among the most significant emitters of greenhouse gasses in the world. In terms of both total and per capita emissions, it is among the largest contributors. The climate policy of the United States has a major influence on the world. Movements and ideas 20th century Both conservationism and environmentalism appeared in political debate in forests about the Progressive Era in the early 20th century. There were three main positions. The laissez-faire position held that owners of private property—including lumber and mining companies—should be allowed to do anything they wished for their property. The Conservationists, led by President The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid Mine Drainage
Acid mine drainage, acid and metalliferous drainage (AMD), or acid rock drainage (ARD) is the outflow of acidic water from metal mines and coal mines. Acid rock drainage occurs naturally within some environments as part of the rock weathering process but is exacerbated by large-scale earth disturbances characteristic of mining and other large construction activities, usually within rocks containing an abundance of sulfide minerals. Areas where the earth has been disturbed (e.g. construction sites or highway construction) may create acid rock drainage. In many localities, the liquid that drains from coal stocks, coal handling facilities, coal washeries, and coal waste tips can be highly acidic, and in such cases it is treated as acid rock drainage. These, combined with reduced pH, have a detrimental impact on the streams' aquatic environments. The same type of chemical reactions and processes may occur through the disturbance of acid sulfate soils formed under coastal or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grass
Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and species cultivated in lawns and pasture. The latter are commonly referred to collectively as grass. With around 780 genera and around 12,000 species, the Poaceae is the fifth-largest :plant families, plant family, following the Asteraceae, Orchidaceae, Fabaceae and Rubiaceae. The Poaceae are the most economically important plant family, including staple foods from domesticated cereal crops such as maize, wheat, rice, oats, barley, and millet for people and as forage, feed for livestock, meat-producing animals. They provide, through direct human consumption, just over one-half (51%) of all dietary energy; rice provides 20%, wheat supplies 20%, maize (corn) 5.5%, and other grains 6%. Some members of the Poaceae are used as building materials ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geotextile
Geotextiles are versatile permeable fabrics that, when used in conjunction with soil, can effectively perform multiple functions, including separation, filtration, reinforcement, protection, and drainage. Typically crafted from polypropylene or polyester, geotextile fabrics are available in two primary forms: woven, which resembles traditional mail bag sacking, and nonwoven, which resembles felt. Geotextile composites have been introduced and products such as geogrids and meshes have been developed. Geotextiles are durable and are able to soften a fall. Overall, these materials are referred to as geosynthetics and each configuration—geonets, geosynthetic clay liners, geogrids, geotextile tubes, and others—can yield benefits in geotechnical engineering, geotechnical and environmental engineering design. History Geotextiles were originally intended to be a substitute for granular soil filters. Geotextiles can also be referred to as ''filter fabrics''. In the 1950s, R.J. Barr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegetation
Vegetation is an assemblage of plants and the ground cover they provide. It is a general term, without specific reference to particular Taxon, taxa, life forms, structure, Spatial ecology, spatial extent, or any other specific Botany, botanical or geographic characteristics. It is broader than the term ''Flora (plants), flora'' which refers to species richness, species composition. Perhaps the closest synonym is ''plant community'', but "vegetation" can, and often does, refer to a wider range of spatial scales than that term does, including scales as large as the global. Primeval redwood forests, coastal mangrove stands, sphagnum bogs, desert soil crusts, Road verge, roadside weed patches, wheat fields, cultivated gardens and lawns; all are encompassed by the term "vegetation". The vegetation type is defined by characteristic dominant species, or a common aspect of the assemblage, such as an elevation range or environmental commonality. The contemporary use of "vegetation" app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
