Longwall Mining Integrity

The Center for Public Integrity is an investigative newsroom that exposes betrayals of the public trust by powerful interests. DONATE. ... Published — June 21, 2013 Updated — May 19, 2014 at 12:19 pm ET New scrutiny of 'longwall' mining finds damage in Pennsylvania streams New scrutiny of 'longwall' mining finds damage in ...

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The Center for Public Integrity is an investigative newsroom that exposes betrayals of the public trust by powerful interests. DONATE. Updates. Menu. Energy ... More in Longwall Mining. Documents. January 12, 2009. Energy Resources. January 12, 2009. Energy The hidden costs of clean coal. January 12, 2009.

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Longwall mining. Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 0.6–1.0 m (2 ft 0 in – 3 ft 3 in) thick). The longwall panel (the block of coal that is being mined) is typically 3–4 km (1.9–2.5 mi) long and 250–400 m (820–1,310 ft) wide.

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longwall-mining-induced wellbore deformation or failure could have a significant adverse impact on well yield, or even in worse cases, resulting in the entrance of oil/gas into the aquifer, polluting ground ... are of critical significance to their integrity. The effect of longwall mining on an oil/gas well is determined by seam burial depth ...

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longwall mining on high-pressure pipelines: – Perform an integrity analysis of pipeline – Perform a longitudinal stress analysis toPerform a longitudinal stress analysis to determine the existing stress on pipeline – Estimate stress from subsidenceEstimate stress from subsidence – Develop a formal mitigation plan

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Now that major coal companies have decided to bring longwall mining to Illinois, citizens are demanding protections for our lands, waters and communities from the threat of longwall mining. Learn More. These organizations work on longwall mining issues in Appalachia: Center for Coalfield Justice; Center for Public Integrity; Citizens Coal Council

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Longwall mining systems are capable of producing significant outputs from a single longwall face – 8 million tones per annum or more. When operating correctly the coal is mined in a systematic, relatively continuous and repetitive process which is ideal for strata control and for associated mining operations. There is a high capital cost for ...

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The high productivity being achieved by longwall mining demonstrates its potential for being a substantial segment of underground coal production. Longwall mines produce more than 30 pct of all underground …

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Longwall mining machines are typically 150-250 meters in width and 1.5 to 3 meter s high. ... integrity of the immedi ate roof above the newly mined coal. This .

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Of India's 204.65 billion tonne coal reserves, around 20% is amenable to open-cast mining. In a technical paper, Dr SK Das, associate professor at the Department of Mining Engineering, Indian Institute of Technology Kharagpur, described longwall mining in India. The first mechanised powered supports were introduced in 1978 at the Moondih mine.

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Longwall Associates is here as your strategic partner…for the long haul. Precision engineered with passion and handcrafted with pride. "Longwall Associates, Inc. has aligned themselves with the most experienced personnel in the industry …

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Longwall Mining, 3rd edition will be of interest to professionals and academics in the field of mining engineering specifically, serving both as a reference work and an (under)graduate textbook, but will also interest civil, geomechanical and geological engineers and rock mechanics professionals, as well as coal operators, mining consultants ...

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The owner of two natural gas transmission pipelines with diameters of 20" and 26" respectively, were subject to disturbance from longwall mining activities occurring far beneath the pipelines. The longwall mining process causes the surface above, including the pipelines, to sink 1-3 meters as coal and minerals were removed from far below.

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Here is how longwall mining works and some of the hazards. It will take days and maybe weeks to know exactly what caused the explosion on Monday afternoon in Massey Energy's Upper Big Branch mine ...

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New scrutiny of 'longwall' mining finds damage in Pennsylvania streams by Kristen Lombardi June 21, 2013 The brutally efficient coal-extraction method known as "longwall mining" has permanently damaged a half dozen streams in Pennsylvania, state regulators have found — a finding that could trigger deeper waves for such operations in the state.

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Longwall mining on the advance involves developing the maingate and tailgate entries just ahead of the longwall face as it is being advanced, with these gateroads being maintained in the goaf of the panel using various combinations …

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Longwall mining activities alter the exsisting ground stress field, this changed stress field is known as induced stress. Extraction of coal by longwall mining induces a redistribution of stresses causing the rocks near the mining excavation to accomodate a redistributed load. Effective and efficient longwall mining is dictated by the […]

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longwall mining Mining. a mining method in which very long rectangular blocks of coal are defined during the development stage of the mine and then extracted in a single continuous operation by an automated cutting head moving parallel to the coal face. When the coal is cut, the working area is protected by a movable, powered roof support system.

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Serious Impacts from Longwall Mining at Deer Run Mine. • Longwall Mining will sink more areas along Route 185 and Surrounding Farm Fields. ... • Montgomery County residents have saced for this longwall mine in many ways: the integrity of farmland, protection of water resources, water and air quality, lost airport, and safety ...

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Integrity of wells vertically piercing the coal pillar is affected by these deformations resulting from surface and subsurface subsidence. ... Longwall mining-induced interfacial shear displacements at interfaces between a monolithic rigid bed (e.g. the key-stratum) and its immediate overlaying and underlaying soft beds (e.g. shales/mudstones ...

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Longwall mining is a highly productive underground process employed to quickly and cheaply extract coal, but the practice comes with a steep environmental price, as documented in a year-long investigation by the Center for Public Integrity, The Hidden Costs of "Clean Coal." As Congress and the incoming Obama administration contemplate alternatives to fossil fuels, …

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The longwall panel is 1000 ft wide and 10,000 ft long. 2. The coal seam has an average thickness of 6 ft. 3. The coal block to be degassed is 1300 ft by 10,000 ft, assuming that the width of chain pillars is 300 ft. 4. The cost of contract drilling for the in-mine horizontal drilling is $50/ft. 5.

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Retreat Longwall Mining Disadvantages Over Advance Longwall Mining Delay in getting production for the preparation of first panel. 27. MAIN GATE WITH SWITCH TRAIN C H O C K S. 28. LONGWALL METHOD …

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Longwall mining of multiple seams has dominated European coal production for decades. In the United Kingdom, the intent is to maximize the gob and to avoid leaving pillars between panels; leaving pillars between panels is known to create stress problems in subsequent workings both above and below. Single entries are utilized in most situations.

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Longwall Mining Through a Graben with Anomalous Stresses at the Deer Creek Mine. Coal, Longwall Mining, Publications: Rock Mechanics, Publications: Stress Measurements. Long Load Transfer Distances at the Deer Creek Mine.

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This paper presents a field monitoring study of longwall mining-induced ground subsidence in Shendong coalfield, China. The paper includes the subsidence data of four longwall panels, with mining and geological conditions varied. All the longwall faces have a high mining height (4.5-7 m) and extraction speed (9.0–13.3 m/day), but with shallow ...

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Longwall. Longwall mining is an efficient mining method and using the right equipment can make it even more profitable. Joy longwall systems incorporate shearers, roof supports, face conveyors and more into one system that can be tightly orchestrated by advanced electronics — including cutting-edge automation. Armored face conveyors.

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Longwall mining is one of the most efficient methods of coal extraction. It is also one of the most demanding. Gates combines world-class material science and expert engineering to manufacture products for the longwall mining industry that can take on the challenges of your longwall mining processes. Underground coal extraction is a complex and ...

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The purpose of Citizens Against Longwall Mining is to oppose the mining of coal using long wall techniques, as well as any other methods that rely on planned subsidence. Our goal is to preserve the land of central Illinois – its value for production agriculture, and its environmental integrity for generations to come. Membership

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Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 1-2 m thick). The longwall "panel" (the block of coal that is being mined) is typically 3-4 km long and 250-400 m wide. Longwall mining produced 176 million tons of coal in 2007, about 15 percent of total U.S. production.

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offers maximum structural integrity and service life. The mainframe is available as a split unit in the event of transportation limitations. Featuring the superior ... developments since 1990 have once again established plowing as the preferred longwall mining method for seams below 1.8 m (71 in). plows offer world-leading features that ...

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with longwall mining is a complex system, understanding a few basic concepts will help to clarify the support design requirements. In any underground mining activity, the in situ vertical and horizontal stresses that exist in the ... structural integrity of damaged or broken ground to provide a stable mine opening. In general,

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The damage of vertical oil/gas wells in longwall mining areas is mainly a result of strata movement induced by coal extraction. Strata with contrasting lithology vary dramatically in …

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Longwall systems. Longwall systems. Joy complete longwall systems represent the ultimate solution for high-production longwall mining. Joy incorporates best-in-breed shearers, roof supports, face conveyors, stageloaders, crushers, and mobile belt tail pieces to deliver a complete longwall system that is in a class of its own.

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