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85-471: It is among the largest sources of acid mine drainage into Catawissa Creek . It also contributes up to 80% of the acidity to Catawissa Creek. The Audenried Tunnel's pH is approximately 4. However, there have been somewhat successful attempts at treating the tunnel outflow in the 21st century. The bedrock in the vicinity of the tunnel is mostly shale and sandstone. The Audenried Tunnel is 16,150 feet (4,920 m) long. The tunnel runs between Audenried Mine and

170-403: A debris flow or mud flow . However, also dry debris can exhibit flow-like movement. Flowing debris or mud may pick up trees, houses and cars, and block bridges and rivers causing flooding along its path. This phenomenon is particularly hazardous in alpine areas, where narrow gorges and steep valleys are conducive of faster flows. Debris and mud flows may initiate on the slopes or result from

255-689: A base metal-free effluent that can be discharged or further treated to reduce sulfate, and a metal sulfide concentrate with possible economic value. As an alternative, several researchers have investigated the precipitation of metals using biogenic sulfide. In this process, sulfate-reducing bacteria (SRB) oxidize organic matter using sulfate as terminal electron acceptor , instead of oxygen . Their metabolic products include bicarbonate produced by organic matter oxidation, which can neutralize water acidity, and hydrogen sulfide , which forms highly insoluble precipitates with many toxic metals. Although promising, this process has been slow in being adopted for

340-466: A depth from few decimeters to some meters) is called a shallow landslide. Debris slides and debris flows are usually shallow. Shallow landslides can often happen in areas that have slopes with high permeable soils on top of low permeable soils. The low permeable soil traps the water in the shallower soil generating high water pressures. As the top soil is filled with water, it can become unstable and slide downslope. Deep-seated landslides are those in which

425-536: A lime silo, a mixing tank and a settling pond. These systems are far less costly to build, but are also less efficient (longer reaction times are required, and they produce a discharge with higher trace metal concentrations, if present). They would be suitable for relatively small flows or less complex acid mine drainage. A calcium silicate feedstock, made from processed steel slag , can also be used to neutralize active acidity in AMD systems by removing free hydrogen ions from

510-436: A load of 71.3 pounds (32.3 kg) per day. The total maximum daily load for iron is 57.1 pounds (25.9 kg) per day, which is 21% less than the current load. The total concentration of manganese at the confluence is 2.28 milligrams per liter, which equates to a load of 232.4 pounds (105.4 kg) per day. The total maximum daily load for manganese is 73% less than the current daily load. The total concentration of aluminum

595-571: A low pH, as is found in the acidic waters produced by pyrite oxidation. In the coal belt around the south Wales valleys in the UK highly acidic nickel-rich discharges from coal stocking sites have proved to be particularly troublesome. Acid mine drainage also affects the wildlife living within the affected body of water. Aquatic macroinvertebrates living in streams or parts of streams affected by acid mine drainage show fewer individuals, less diversity, and lower biomass. Many species of fish also cannot tolerate

680-544: A low shearing resistance. On the slopes, some earthflow may be recognized by their elongated shape, with one or more lobes at their toes. As these lobes spread out, drainage of the mass increases and the margins dry out, lowering the overall velocity of the flow. This process also causes the flow to thicken. Earthflows occur more often during periods of high precipitation, which saturates the ground and builds up water pressures. However, earthflows that keep advancing also during dry seasons are not uncommon. Fissures may develop during

765-424: A poorly soluble calcium sulfate layer onto the surface of limestone chips, binding the material and preventing further neutralization. Depending on the volume and flowrate of acid effluents to be neutralised and the scale of industrial installations, a commonly but more expensive commercial process for treating acid mine drainage is precipitation with lime in a high-density sludge (HDS) process. In this application,

850-530: A reconstruction of the evolution of a particular landslide. Therefore, landslide hazard mitigation measures are not generally classified according to the phenomenon that might cause a landslide. Instead, they are classified by the sort of slope stabilization method used: Climate-change impact on temperature, both average rainfall and rainfall extremes, and evapotranspiration may affect landslide distribution, frequency and intensity (62). However, this impact shows strong variability in different areas (63). Therefore,

935-542: A slope prone to failure. In many cases, the landslide is triggered by a specific event (such as a heavy rainfall , an earthquake , a slope cut to build a road, and many others), although this is not always identifiable. Landslides are frequently made worse by human development (such as urban sprawl ) and resource exploitation (such as mining and deforestation ). Land degradation frequently leads to less stabilization of soil by vegetation . Additionally, global warming caused by climate change and other human impact on

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1020-414: A slurry of lime ( CaO – Ca(OH) 2 after hydration) is dispersed into a tank containing acid mine drainage and recycled sludge to increase water pH to about 9. At this pH, most toxic metals become insoluble and precipitate, aided by the presence of recycled sludge. Optionally, air can be injected in the tank to oxidize iron(II) and manganese(II) and assist in their precipitation. The resulting slurry

1105-596: A source for effective drugs and new research, such as that conducted at the Center for Pharmaceutical Research and Innovation , suggests these extreme environments to be an untapped source for new discovery. This list includes both mines producing acid mine drainage and river systems significantly affected by such drainage. It is by no means complete, as worldwide, several thousands of such sites exist. Landslide Landslides , also known as landslips , or rockslides , are several forms of mass wasting that may include

1190-561: A stable dispersed state – effectively interrupting metal precipitation and reducing vulnerability of the material to armoring (formation of an impervious crust around material grains preventing their dissolution and decreasing their reactivity). Cation exchange processes have previously been investigated as a potential treatment for acid mine drainage. The principle is that an ion-exchange resin can remove potentially toxic metals (cationic resins), or chlorides, sulfates and uranyl sulfate complexes (anionic resins) from mine water . Once

1275-743: A variety of technical reasons. Many technologies exist for the treatment of AMD. With the advance of large-scale sequencing strategies , genomes of microorganisms in the acid mine drainage community are directly sequenced from the environment. The nearly full genomic constructs allows new understanding of the community and able to reconstruct their metabolic pathways. Our knowledge of acidophiles in acid mine drainage remains rudimentary: we know of many more species associated with ARD than we can establish roles and functions. Scientists have recently begun to explore acid mine drainage and mine reclamation sites for unique soil bacteria capable of producing new pharmaceutical leads. Soil microbes have long been

1360-430: A very wide range, from as low as 1 mm/yr to many km/h. Though these are a lot like mudflows , overall they are more slow-moving and are covered with solid material carried along by the flow from within. Clay, fine sand and silt, and fine-grained, pyroclastic material are all susceptible to earthflows. These flows are usually controlled by the pore water pressures within the mass, which should be high enough to produce

1445-534: A way to neutralize the water in the Audenried Tunnel. The Audenried Tunnel AMD Treatment Project began in the summer of 2005, with the aim of treating the outflow of the Audenried Tunnel. The Eastern Pennsylvania Coalition for Abandoned Mine Reclamation gained $ 150,000 from the Office of Surface Mining for the project. The treatment cost approximately $ 1,900,000 and is the largest acid mine drainage treatment system in

1530-518: A wide range of ground movements, such as rockfalls , mudflows , shallow or deep-seated slope failures and debris flows . Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides . Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make

1615-566: A yellow-orange solid colloquially known as yellow boy . Other types of iron precipitates are possible, including iron oxides and oxyhydroxides, and sulfates such as jarosite . All these precipitates can discolor water and smother plant and animal life on the streambed, disrupting stream ecosystems (a specific offense under the Fisheries Act in Canada). The process also produces additional hydrogen ions, which can further decrease pH. In some cases,

1700-477: Is 12.0 feet (3.7 m) in width and 9.0 feet (2.7 m) in height. When the Audenried Tunnel was first built, the first 350 feet (110 m) were fully lined with timber due to the low quality of the rock in that part of the tunnel. The next 150 feet (46 m) were also supported by timber, but to a lesser extent. In 1931, the Glen Alden Coal Company reported that 8,499 feet (2,590 m) from

1785-418: Is 7.93 milligrams per liter, which equates to a load of 808.2 pounds (366.6 kg) per day. The total maximum daily load for aluminum is 40.8 pounds (18.5 kg), which is 95% less than the current daily load. The total concentration of acidity is 68.08 milligrams per liter, which equates to 6,938.4 pounds (3,147.2 kg) per day. The total maximum daily load for acidity is 69.3 pounds (31.4 kg), which

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1870-421: Is 99% less than the current load. The total concentration of alkalinity is 2.31 milligrams per liter, which equates to 235.4 pounds (106.8 kg) per day. The total concentration of sulfates in the discharge is 136.25 milligrams per liter. The Glen Alden Coal Company commenced construction of the Audenried Tunnel in 1928. Construction of the tunnel finished in 1931. The tunnel was originally created to decrease

1955-719: Is an appropriate tool because it has functions of collection, storage, manipulation, display, and analysis of large amounts of spatially referenced data which can be handled fast and effectively. Cardenas reported evidence on the exhaustive use of GIS in conjunction of uncertainty modelling tools for landslide mapping. Remote sensing techniques are also highly employed for landslide hazard assessment and analysis. Before and after aerial photographs and satellite imagery are used to gather landslide characteristics, like distribution and classification, and factors like slope, lithology , and land use/land cover to be used to help predict future events. Before and after imagery also helps to reveal how

2040-438: Is an unprocessed raw material available in large quantities and the least expensive neutralisation agent, it can suffer from a number of disadvantages possibly limiting its applications. Indeed, small calcium carbonate grains of crushed limestone can be prone to the formation of a coating of gypsum ( CaSO 4 ·2H 2 O ) surrounded by a thin impermeable and protective film of less soluble Fe-Al hydroxysulfate. This coating

2125-481: Is considered a serious long-term environmental problem associated with mining. The chemistry of oxidation of pyrites, the production of ferrous ions and subsequently ferric ions, is very complex, and this complexity has considerably inhibited the design of effective treatment options. Although a host of chemical processes contribute to acid mine drainage, pyrite oxidation is by far the greatest contributor. A general equation for this process is: The oxidation of

2210-434: Is determined by certain geologic factors, and that future landslides will occur under the same conditions as past events. Therefore, it is necessary to establish a relationship between the geomorphologic conditions in which the past events took place and the expected future conditions. Natural disasters are a dramatic example of people living in conflict with the environment. Early predictions and warnings are essential for

2295-768: Is directed to a sludge-settling vessel, such as a clarifier . In that vessel, clean water will overflow for release, whereas settled metal precipitates (sludge) are recycled to the acid mine drainage treatment tank, with a sludge-wasting side stream. A number of variations of this process exist, as dictated by the chemistry of ARD, its volume, and other factors. Generally, the products of the HDS process also contain gypsum ( CaSO 4 ) and unreacted lime, which enhance both its settleability and resistance to re-acidification and metal mobilization. A general equation for this neutralisation process is: Less complex variants of this process, such as simple lime neutralization, may involve no more than

2380-514: Is essentially due to a decrease in the shear strength of the slope material, an increase in the shear stress borne by the material, or a combination of the two. A change in the stability of a slope can be caused by a number of factors, acting together or alone. Natural causes of landslides include: Landslides are aggravated by human activities, such as: In traditional usage, the term landslide has at one time or another been used to cover almost all forms of mass movement of rocks and regolith at

2465-457: Is fluid-like and generally much more rapid. This is usually a result of lower shear resistances and steeper slopes. Typically, debris slides start with the detachment of large rock fragments high on the slopes, which break apart as they descend. Clay and silt slides are usually slow but can experience episodic acceleration in response to heavy rainfall or rapid snowmelt. They are often seen on gentle slopes and move over planar surfaces, such as over

2550-476: Is iron-sulfide) within the surrounding rock and overburden generates acidity. Colonies of bacteria and archaea greatly accelerate the decomposition of metal ions, although the reactions also occur in an abiotic environment. These microbes, called extremophiles for their ability to survive in harsh conditions, occur naturally in the rock, but limited water and oxygen supplies usually keep their numbers low. Extremophiles known as acidophiles especially favor

2635-426: Is itself a copper-iron-sulfide and occurs with a range of other sulfides. Thus, copper mines are often major culprits of acid mine drainage. At some mines, acidic drainage is detected within 2–5 years after mining begins, whereas at other mines, it is not detected for several decades. In addition, acidic drainage may be generated for decades or centuries after it is first detected. For this reason, acid mine drainage

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2720-544: Is provided below. Under this classification, six types of movement are recognized. Each type can be seen both in rock and in soil. A fall is a movement of isolated blocks or chunks of soil in free-fall. The term topple refers to blocks coming away by rotation from a vertical face. A slide is the movement of a body of material that generally remains intact while moving over one or several inclined surfaces or thin layers of material (also called shear zones) in which large deformations are concentrated. Slides are also sub-classified by

2805-401: Is quite different from limestone, the ability of calcium silicate to neutralize acid solutions is equivalent to limestone as evidenced by its CCE value of 90–100% and its relative neutralizing value of 98% . In the presence of heavy metals, calcium silicate reacts in a different way than limestone. As limestone raises the pH of the bulk solution, when heavy metals are present, precipitation of

2890-403: Is sometimes referred to in the literature as an armor (shield, encrustation, rim, rind…). When present, it passivates the limestone surface, preventing calcite dissolution and the further release of bicarbonate in solution. This might explain why at Cwm Rheidol in mid Wales , the positive impact of limestone application has been much less than anticipated because of the formation of

2975-522: 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 estuarine conditions after the last major sea level rise , and constitutes a similar environmental hazard . Historically, the acidic discharges from active or abandoned mines were called acid mine drainage, or AMD. The term acid rock drainage, or ARD,

3060-461: The Coal Region . Around 2000, plans were made to reroute Catawissa Creek away from the tunnel. The Audenried Tunnel AMD Treatment Project takes in water from the Audenried Tunnel and puts it in three concrete tanks that are 120 feet (37 m) wide and 10 feet (3.0 m) deep. The tanks are filled with 4500 tons of limestone . The treatment system raises the pH of the water by 30%. Ed Rendell ,

3145-468: The River Neath at Ynysarwed . Although abandoned underground mines produce most of the acid mine drainage, some recently mined and reclaimed surface mines have produced ARD and have degraded local ground-water and surface-water resources. Acidic water produced at active mines must be neutralized to achieve pH 6–9 before discharge from a mine site to a stream is permitted. In Canada, work to reduce

3230-518: The coal mine discharges in Pennsylvania have pH under 5. However, a portion of mine drainage in both the bituminous and anthracite regions of Pennsylvania is alkaline, because limestone in the overburden neutralizes acid before the drainage emanates. When the pH of acid mine drainage is raised past 3, either through contact with fresh water or neutralizing minerals, previously soluble iron(III) ions precipitate as iron(III) hydroxide ,

3315-676: The 1980s to treat acid mine drainage generated by the abandoned coal mines in Eastern Appalachia . Generally, the wetlands receive near-neutral water, after it has been typically neutralized by a limestone-based treatment process. Metal precipitation occurs from their oxidation at near-neutral pH, complexation with organic matter, precipitation as carbonates or sulfides. The latter results from sediment-borne anaerobic bacteria capable of reducing sulfate ions into sulfide ions. These sulfide ions can then bind with heavy metal ions, precipitating heavy metals out of solution and effectively reversing

3400-462: The Earth's surface. In 1978, geologist David Varnes noted this imprecise usage and proposed a new, much tighter scheme for the classification of mass movements and subsidence processes. This scheme was later modified by Cruden and Varnes in 1996, and refined by Hutchinson (1988), Hungr et al. (2001), and finally by Hungr, Leroueil and Picarelli (2014). The classification resulting from the latest update

3485-695: The United Kingdom, many discharges from abandoned mines are exempt from regulatory control. In such cases the Environment Agency and Natural Resources Wales working with partners such as the Coal Authority have provided some innovative solutions, including constructed wetland solutions such as on the River Pelenna in the valley of the River Afan near Port Talbot and the constructed wetland next to

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3570-626: The area of the Val Pola disaster (Italy). Evidence of past landslides has been detected on many bodies in the solar system, but since most observations are made by probes that only observe for a limited time and most bodies in the solar system appear to be geologically inactive not many landslides are known to have happened in recent times. Both Venus and Mars have been subject to long-term mapping by orbiting satellites, and examples of landslides have been observed on both planets. Landslide mitigation refers to several human-made activities on slopes with

3655-522: The bedrock around the tunnel is largely sandstone. Up to 8,499 feet (2,590 m), the rock near the Audenried Tunnel is mostly interbedded red shale and sandstone. However, there is also a 29 feet (8.8 m) layer of conglomerate . 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

3740-416: The bulk solution, thereby increasing pH. As the silicate anion captures H ions (raising the pH), it forms monosilicic acid (H 4 SiO 4 ), a neutral solute. Monosilicic acid remains in the bulk solution and play many roles in correcting the adverse effects of acidic conditions. In the bulk solution, the silicate anion is very effective in neutralizing H cations in the soil solution. While its mode-of-action

3825-458: The calcium silicate aggregates , as silicic acid species are adsorbed onto the metal hydroxide surface, the development of silica layers (mono- and bi-layers) lead to the formation of colloidal complexes with neutral or negative surface charges. These negatively charged colloids are electrostatically repelled by each other (as well as with the negatively charged calcium silicate granules). The sequestered metal colloids are stabilized and remain in

3910-438: The concentrations of iron hydroxides in yellow boy are so high, the precipitate can be recovered for commercial use in pigments. Many acid rock discharges also contain elevated levels of potentially toxic metals, especially nickel and copper with lower levels of a range of trace and semi-metal ions such as lead , arsenic , aluminium , and manganese . The elevated levels of heavy metals can only be dissolved in waters that have

3995-472: The contaminants are adsorbed , the exchange sites on resins must be regenerated, which typically requires acidic and basic reagents and generates a brine that contains the pollutants in a concentrated form. A South African company that won the 2013 IChemE award for water management and supply (treating AMD) has developed a patented ion-exchange process that treats mine effluents (and AMD) economically. Constructed wetlands systems have been proposed during

4080-482: The creek. The Audenried Tunnel discharges in a strip mine not far from Catawissa Creek's headwaters. All of the mine workings in the Jeansville Coal Basin likely drain into the tunnel, as does some water from the surface. The discharge from the Audenried Tunnel contributes currently as much as 80% of the acid flowing through Catawissa Creek, with previous studies showing up to 84%. The average discharge of

4165-579: The development of guidelines for sustainable land-use planning . The analysis is used to identify the factors that are related to landslides, estimate the relative contribution of factors causing slope failures, establish a relation between the factors and landslides, and to predict the landslide hazard in the future based on such a relationship. The factors that have been used for landslide hazard analysis can usually be grouped into geomorphology , geology , land use/land cover, and hydrogeology . Since many factors are considered for landslide hazard mapping, GIS

4250-856: The effects of acid mine drainage is concentrated under the Mine Environment Neutral Drainage (MEND) program. Total liability from acid rock drainage is estimated to be between CA$ 2 billion and CA$ 5 billion . Over a period of eight years, MEND claims to have reduced ARD liability by up to CA$ 400 million , from an investment of CA$ 17.5 million . Often, limestone rocks or appropriate calcareous strata that could contribute to neutralize acid effluents are lacking, or insufficiently accessible (too short contact time with acidic waters flowing too fast, too low specific surface area , insufficient contact…), at sites affected by acidic rock drainage. In such cases, crushed limestone can be dumped on site as neutralizing agent. However, although limestone

4335-468: The effects of climate change on landslides need to be studied on a regional scale. Climate change can have both positive and negative impacts on landslides Temperature rise may increase evapotranspiration, leading to a reduction in soil moisture and stimulate vegetation growth, also due to a CO2 increase in the atmosphere. Both effects may reduce landslides in some conditions. On the other side, temperature rise causes an increase of landslides due to Since

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4420-502: The effluent from constructed wetland receiving near-neutral water will be well-buffered at 6.5–7.0 and can readily be discharged. Some of metal precipitates retained in sediments are easily oxidised and remobilised when exposed to atmospheric oxygen (e.g., copper sulfide or elemental selenium ), and it is very important that the wetland sediments remain largely and permanently submerged to maintain them insoluble and immobile. Prolonged droughts caused by climate warming might compromise

4505-412: The elevation of the area's water table without resorting to the use of pumps , thus allowing the drilling of deep coal mine shafts . It was successful in doing this, but rendered 33 miles (53 km) of Catawissa Creek devoid of life for 75 years. An attempt was made to map the Audenried Tunnel in 1971. However, the attempt was aborted after 1,300 feet (400 m) due to the presence of debris that

4590-441: The entire process. The attractiveness of a constructed wetlands solution lies in its relative low cost. They are limited by the metal loads they can deal with (either from high flows or metal concentrations), though current practitioners have succeeded in developing constructed wetlands that treat high volumes (see description of Campbell Mine constructed wetland ) and/or highly acidic water (with adequate pre-treatment). Typically,

4675-406: The environment , can increase the frequency of natural events (such as extreme weather ) which trigger landslides. Landslide mitigation describes the policy and practices for reducing the risk of human impacts of landslides, reducing the risk of natural disaster . Landslides occur when the slope (or a portion of it) undergoes some processes that change its condition from stable to unstable. This

4760-452: The fluidization of landslide material as it gains speed or incorporates further debris and water along its path. River blockages as the flow reaches a main stream can generate temporary dams. As the impoundments fail, a domino effect may be created, with a remarkable growth in the volume of the flowing mass, and in its destructive power. An earthflow is the downslope movement of mostly fine-grained material. Earthflows can move at speeds within

4845-713: The form of the surface(s) or shear zone(s) on which movement happens. The planes may be broadly parallel to the surface ("planar slides") or spoon-shaped ("rotational slides"). Slides can occur catastrophically, but movement on the surface can also be gradual and progressive. Spreads are a form of subsidence, in which a layer of material cracks, opens up, and expands laterally. Flows are the movement of fluidised material, which can be both dry or rich in water (such as in mud flows). Flows can move imperceptibly for years, or accelerate rapidly and cause disasters. Slope deformations are slow, distributed movements that can affect entire mountain slopes or portions of it. Some landslides are complex in

4930-462: The goal of lessening the effect of landslides. Landslides can be triggered by many, sometimes concomitant causes. In addition to shallow erosion or reduction of shear strength caused by seasonal rainfall , landslides may be triggered by anthropic activities, such as adding excessive weight above the slope, digging at mid-slope or at the foot of the slope. Often, individual phenomena join to generate instability over time, which often does not allow

5015-494: The governor of Pennsylvania when this project was worked on, granted $ 200,000 to the project. The bedrock around the Audenried Tunnel includes red shale , sandy shale, which are both clay -like or silt -like. The shale is more weathered near the mouth of the tunnel. The bedrock near the tunnel also includes sandstone belonging to the Mauch Chunk Formation . Between 1,000 feet (300 m) and 1,200 feet (370 m),

5100-480: The landscape changed after an event, what may have triggered the landslide, and shows the process of regeneration and recovery. Using satellite imagery in combination with GIS and on-the-ground studies, it is possible to generate maps of likely occurrences of future landslides. Such maps should show the locations of previous events as well as clearly indicate the probable locations of future events. In general, to predict landslides, one must assume that their occurrence

5185-440: The long runout can be different, but they typically result in the weakening of the sliding mass as the speed increases. The causes of this weakening are not completely understood. Especially for the largest landslides, it may involve the very quick heating of the shear zone due to friction, which may even cause the water that is present to vaporize and build up a large pressure, producing a sort of hovercraft effect. In some cases,

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5270-409: The low pH levels of abandoned mines. In particular, Acidithiobacillus ferrooxidans is a key contributor to pyrite oxidation. Metal mines may generate highly acidic discharges where the ore is a sulfide mineral or is associated with pyrite. In these cases the predominant metal ion may not be iron but rather zinc , copper , or nickel . The most commonly mined ore of copper, chalcopyrite ,

5355-415: The mine in order to prevent flooding. When a mine is abandoned, the pumping ceases, and water floods the mine. This introduction of water is the initial step in most acid rock drainage situations. Tailings piles or ponds, mine waste rock dumps , and coal spoils are also an important source of acid mine drainage. After being exposed to air and water, oxidation of metal sulfides (often pyrite , which

5440-444: The more generic name. In cases where drainage from a mine is not acidic and has dissolved metals or metalloids , or was originally acidic, but has been neutralized along its flow path, then it is described as "neutral mine drainage", "mining-influenced water" or otherwise. None of these other names have gained general acceptance. Sub-surface mining often progresses below the water table , so water must be constantly pumped out of

5525-413: The most important factors that trigger landslides in any given location. Using GIS, extremely detailed maps can be generated to show past events and likely future events which have the potential to save lives, property, and money. Since the ‘90s, GIS have been also successfully used in conjunction to decision support systems , to show on a map real-time risk evaluations based on monitoring data gathered in

5610-548: The mouth of the Audenried Tunnel, there was a fissure that discharged close to 800 gallons (approximately 211 liters) per minute. It is possible that there is a fault at this location. The Audenried Tunnel is the most downstream mine drainage tunnel to discharge into Catawissa Creek. The Audenried Tunnel discharges into Catawissa Creek near where the Green Mountain Tunnel and the Catawissa Tunnel discharge into

5695-431: The movement of a mass over a planar or curvilinear surface or shear zone. A debris slide is a type of slide characterized by the chaotic movement of material mixed with water and/or ice. It is usually triggered by the saturation of thickly vegetated slopes which results in an incoherent mixture of broken timber, smaller vegetation and other debris. Debris flows and avalanches differ from debris slides because their movement

5780-471: The movement of clayey materials, which facilitate the intrusion of water into the moving mass and produce faster responses to precipitation. A rock avalanche, sometimes referred to as sturzstrom , is a large and fast-moving landslide of the flow type. It is rarer than other types of landslides but it is often very destructive. It exhibits typically a long runout, flowing very far over a low-angle, flat, or even slightly uphill terrain. The mechanisms favoring

5865-451: The negative impacts felt by landslides. GIS offers a superior method for landslide analysis because it allows one to capture, store, manipulate, analyze, and display large amounts of data quickly and effectively. Because so many variables are involved, it is important to be able to overlay the many layers of data to develop a full and accurate portrayal of what is taking place on the Earth's surface. Researchers need to know which variables are

5950-498: The pH and maintains the solubility of the ferric ion. Water temperatures as high as 47 °C (117 °F) have been measured underground at the Iron Mountain Mine , and the pH can be as low as −3.6. Organisms which cause acid mine drainage can thrive in waters with pH very close to zero. Negative pH occurs when water evaporates from already acidic pools thereby increasing the concentration of hydrogen ions. About half of

6035-532: The pollution. Among the macroinvertebrates, certain species can be found at only certain levels of pollution, while other species can be found over a wide range. In a mining setting it is leading practice to carry out a geochemical assessment of mine materials during the early stages of a project to determine the potential for AMD. The geochemical assessment aims to map the distribution and variability of key geochemical parameters, acid generating and element leaching characteristics. The assessment may include: In

6120-519: The poorly soluble metal hydroxides is accelerated and the tendency for an impermeable metal hydroxide coating, termed armoring , to form on limestone grains surface increases significantly. Limestone grains become coated by a rind of gypsum encapsulated itself in a thin external film of impermeable and protective Fe-Al hydroxysulfate. Armoring slows the CaCO 3 dissolution and prevents the limestone grains from releasing additional alkalinity in solution. In

6205-659: The proper functioning and the safety of some constructed wetlands if during extremely hot summer period water supply decreases and evaporation accelerates causing them to dry up. An example of an effective constructed wetland is on the Afon Pelena in the River Afan valley above Port Talbot where highly ferruginous discharges from the Whitworth mine have been successfully treated. Most base metals in acidic solution precipitate in contact with free sulfide, e.g. from H 2 S or NaHS. Solid-liquid separation after reaction would produce

6290-402: The reduction of property damage and loss of life. Because landslides occur frequently and can represent some of the most destructive forces on earth, it is imperative to have a good understanding as to what causes them and how people can either help prevent them from occurring or simply avoid them when they do occur. Sustainable land management and development is also an essential key to reducing

6375-510: 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

6460-489: The sense that they feature different movement types in different portions of the moving body, or they evolve from one movement type to another over time. For example, a landslide can initiate as a rock fall or topple and then, as the blocks disintegrate upon the impact, transform into a debris slide or flow. An avalanching effect can also be present, in which the moving mass entrains additional material along its path. Slope material that becomes saturated with water may produce

6545-412: The sliding surface is mostly deeply located, for instance well below the maximum rooting depth of trees. They usually involve deep regolith , weathered rock, and/or bedrock and include large slope failures associated with translational, rotational, or complex movements. They tend to form along a plane of weakness such as a fault or bedding plane . They can be visually identified by concave scarps at

6630-426: The sulfide to sulfate solubilizes the ferrous iron ( iron(II) ), which is subsequently oxidized to ferric iron ( iron(III) ): Either of these reactions can occur spontaneously or can be catalyzed by microorganisms that derive energy from the oxidation reaction. The ferric cations produced can also oxidize additional pyrite and reduce into ferrous ions: The net effect of these reactions is to release H , which lowers

6715-716: The top and steep areas at the toe. Deep-seated landslides also shape landscapes over geological timescales and produce sediment that strongly alters the course of fluvial streams . Landslides that occur undersea, or have impact into water e.g. significant rockfall or volcanic collapse into the sea, can generate tsunamis . Massive landslides can also generate megatsunamis , which are usually hundreds of meters high. In 1958, one such tsunami occurred in Lituya Bay in Alaska. Landslide hazard analysis and mapping can provide useful information for catastrophic loss reduction, and assist in

6800-414: The tunnel is 12.22 million gallons per day, or about 8500 gallons per minute. However, during heavy rainstorms , the discharge can reach 300,000 gallons per minute. The pH of the water in the tunnel ranges between 3.8 and 4.1. The average pH is 4.03. The total concentration of iron in the waters at the confluence of the Audenried Tunnel and Catawissa Creek is 0.7 milligrams per liter, which equates to

6885-413: The underlying bedrock. Failure surfaces can also form within the clay or silt layer itself, and they usually have concave shapes, resulting in rotational slides Slope failure mechanisms often contain large uncertainties and could be significantly affected by heterogeneity of soil properties. A landslide in which the sliding surface is located within the soil mantle or weathered bedrock (typically to

6970-474: The very high temperature may even cause some of the minerals to melt. During the movement, the rock in the shear zone may also be finely ground, producing a nanometer-size mineral powder that may act as a lubricant, reducing the resistance to motion and promoting larger speeds and longer runouts. The weakening mechanisms in large rock avalanches are similar to those occurring in seismic faults. Slides can occur in any rock or soil material and are characterized by

7055-412: The watershed of Catawissa Creek. It is filled with debris and the air inside the tunnel is not breathable. The tunnel roughly follows the synclinal axis of the coal basin it is in. The tunnel drains the Jeansville Coal Basin, which is located between Hazleton and McAdoo . The Audenried Tunnel is located approximately 2 miles (3.2 km) east of the community of Sheppton, Pennsylvania . The tunnel

7140-402: Was impassible. Plans were made in 1974 to plug the tunnel. In 2006, part of the treatment plant at the mouth of the Audenried Tunnel was buried by a landslide , putting it out of commission. One plan to reduce the discharge rate of the Audenried Tunnel is to reclaim land and create stream channels for Hunkydory Creek and two unnamed tributaries of Catawissa Creek. There are plans to test

7225-452: Was introduced in the 1980s and 1990s to indicate that acidic drainage can originate from sources other than mines. For example, a paper presented in 1991 at a major international conference on this subject was titled: "The Prediction of Acid Rock Drainage – Lessons from the Database". Both AMD and ARD refer to low pH or acidic waters caused by the oxidation of sulfide minerals , though ARD is

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