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111-423: The artificial lake was completed in 1975 and is located in both Beaver County, Pennsylvania and Hancock County, West Virginia and is owned by FirstEnergy , a publicly traded company with assets worth $ 48 billion in 2010. Before Little Blue Run Lake was created, the power company told local residents that the project would create a local recreational and boating area. The lake covers 1,900 acres (770 ha) and

222-519: A direct bandgap , and can be used in laser diodes and LEDs to convert electrical energy directly into light. After World War I , the United States built a stockpile of 20,000 tons of weaponized lewisite (ClCH=CHAsCl 2 ), an organoarsenic vesicant (blister agent) and lung irritant. The stockpile was neutralized with bleach and dumped into the Gulf of Mexico in the 1950s. During

333-568: A tetrahedral structure in which each atom is bound to each of the other three atoms by a single bond. This unstable allotrope, being molecular, is the most volatile, least dense, and most toxic. Solid yellow arsenic is produced by rapid cooling of arsenic vapor, As 4 . It is rapidly transformed into grey arsenic by light. The yellow form has a density of 1.97 g/cm . Black arsenic is similar in structure to black phosphorus . Black arsenic can also be formed by cooling vapor at around 100–220 °C and by crystallization of amorphous arsenic in

444-554: A wood preservative . In the 1930s, a process of treating wood with chromated copper arsenate (also known as CCA or Tanalith ) was invented, and for decades, this treatment was the most extensive industrial use of arsenic. An increased appreciation of the toxicity of arsenic led to a ban of CCA in consumer products in 2004, initiated by the European Union and United States. However, CCA remains in heavy use in other countries (such as on Malaysian rubber plantations). Arsenic

555-544: A 60 day notice of intent to sue waiting period, the PADEP filed the first ever state lawsuit for a coal ash disposal site. This state action was taken against FirstEnergy because the Little Blue Run Impoundment caused a potential "imminent and substantial endangerment" to human health and the environment. Simultaneously the PADEP filed its lawsuit and a consent decree in federal court seeking the closure of

666-409: A body of water from 2 hectares (5 acres) to 8 hectares (20 acres). Pioneering animal ecologist Charles Elton regarded lakes as waterbodies of 40 hectares (99 acres) or more. The term lake is also used to describe a feature such as Lake Eyre , which is a dry basin most of the time but may become filled under seasonal conditions of heavy rainfall. In common usage, many lakes bear names ending with

777-500: A comprehensive analysis of the origin of lakes and proposed what is a widely accepted classification of lakes according to their origin. This classification recognizes 11 major lake types that are divided into 76 subtypes. The 11 major lake types are: Tectonic lakes are lakes formed by the deformation and resulting lateral and vertical movements of the Earth's crust. These movements include faulting, tilting, folding, and warping. Some of

888-490: A distorted octahedral complex, with the three atoms in the same double-layer being slightly closer than the three atoms in the next. This relatively close packing leads to a high density of 5.73 g/cm . Grey arsenic is a semimetal , but becomes a semiconductor with a bandgap of 1.2–1.4 eV if amorphized . Grey arsenic is also the most stable form. Yellow arsenic is soft and waxy, and somewhat similar to tetraphosphorus ( P 4 ). Both have four atoms arranged in

999-402: A form of organic lake. They form where a buildup of partly decomposed plant material in a wet environment leaves the vegetated surface below the water table for a sustained period of time. They are often low in nutrients and mildly acidic, with bottom waters low in dissolved oxygen. Artificial lakes or anthropogenic lakes are large waterbodies created by human activity . They can be formed by

1110-538: A higher perimeter to area ratio than other lake types. These form where sediment from a tributary blocks the main river. These form where sediment from the main river blocks a tributary, usually in the form of a levee . Lakes formed by other processes responsible for floodplain basin creation. During high floods they are flushed with river water. There are four types: 1. Confluent floodplain lake, 2. Contrafluent-confluent floodplain lake, 3. Contrafluent floodplain lake, 4. Profundal floodplain lake. A solution lake

1221-510: A hypolimnion; accordingly, very shallow lakes are excluded from this classification system. Based upon their thermal stratification, lakes are classified as either holomictic , with a uniform temperature and density from top to bottom at a given time of year, or meromictic , with layers of water of different temperature and density that do not intermix. The deepest layer of water in a meromictic lake does not contain any dissolved oxygen so there are no living aerobic organisms . Consequently,

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1332-428: A lake consists of a large area of standing water that occupies an extensive closed depression in limestone, it is also called a karst lake . Smaller solution lakes that consist of a body of standing water in a closed depression within a karst region are known as karst ponds. Limestone caves often contain pools of standing water, which are known as underground lakes . Classic examples of solution lakes are abundant in

1443-470: A large number of studies agree that small ponds are much more abundant than large lakes. For example, one widely cited study estimated that Earth has 304 million lakes and ponds, and that 91% of these are 1 hectare (2.5 acres) or less in area. Despite the overwhelming abundance of ponds, almost all of Earth's lake water is found in fewer than 100 large lakes; this is because lake volume scales superlinearly with lake area. Extraterrestrial lakes exist on

1554-517: A major source of arsenic contamination of groundwater in regions with high levels of naturally-occurring arsenic minerals. Synthetic arsenates include Scheele's Green (cupric hydrogen arsenate, acidic copper arsenate), calcium arsenate , and lead hydrogen arsenate . These three have been used as agricultural insecticides and poisons . The protonation steps between the arsenate and arsenic acid are similar to those between phosphate and phosphoric acid . Unlike phosphorous acid , arsenous acid

1665-489: A natural outflow and lose water solely by evaporation or underground seepage, or both. These are termed endorheic lakes. Many lakes are artificial and are constructed for hydroelectric power generation, aesthetic purposes, recreational purposes, industrial use, agricultural use, or domestic water supply . The number of lakes on Earth is undetermined because most lakes and ponds are very small and do not appear on maps or satellite imagery . Despite this uncertainty,

1776-470: A notice of intent to sue letter was filed by The Environmental Integrity Project and Public Justice on May 30, 2012. The notice of Intent alleged that toxic pollution and leaks from the Little Blue Run Impoundment violated State and Federal environmental laws. The leaks from the Impoundment allowed boron, manganese, sulfates, arsenic, and other pollutants to discharge into local water sources. On day 59 of

1887-483: A pure elemental crystal . It has various allotropes , but only the grey form, which has a metallic appearance, is important to industry. The primary use of arsenic is in alloys of lead (for example, in car batteries and ammunition ). Arsenic is a common n-type dopant in semiconductor electronic devices. It is also a component of the III–V compound semiconductor gallium arsenide . Arsenic and its compounds, especially

1998-403: A result of meandering. The slow-moving river forms a sinuous shape as the outer side of bends are eroded away more rapidly than the inner side. Eventually a horseshoe bend is formed and the river cuts through the narrow neck. This new passage then forms the main passage for the river and the ends of the bend become silted up, thus forming a bow-shaped lake. Their crescent shape gives oxbow lakes

2109-535: A result of the 1959 Hebgen Lake earthquake . Most landslide lakes disappear in the first few months after formation, but a landslide dam can burst suddenly at a later stage and threaten the population downstream when the lake water drains out. In 1911, an earthquake triggered a landslide that blocked a deep valley in the Pamir Mountains region of Tajikistan , forming the Sarez Lake . The Usoi Dam at

2220-532: A role in human metabolism. However, arsenic poisoning occurs in multicellular life if quantities are larger than needed. Arsenic contamination of groundwater is a problem that affects millions of people across the world. The United States' Environmental Protection Agency states that all forms of arsenic are a serious risk to human health. The United States' Agency for Toxic Substances and Disease Registry ranked arsenic number 1 in its 2001 prioritized list of hazardous substances at Superfund sites. Arsenic

2331-591: A subsidiary of Pfizer Inc., which produces roxarsone, voluntarily suspended sales of the drug in response to studies showing elevated levels of inorganic arsenic, a carcinogen, in treated chickens. A successor to Alpharma, Zoetis , continued to sell nitarsone until 2015, primarily for use in turkeys. During the 17th, 18th, and 19th centuries, a number of arsenic compounds were used as medicines, including arsphenamine (by Paul Ehrlich ) and arsenic trioxide (by Thomas Fowler ), for treating diseases such as cancer or psoriasis . Arsphenamine, as well as neosalvarsan ,

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2442-422: A variation in density because of thermal gradients. Stratification can also result from a density variation caused by gradients in salinity. In this case, the hypolimnion and epilimnion are separated not by a thermocline but by a halocline , which is sometimes referred to as a chemocline . Lakes are informally classified and named according to the seasonal variation in their lake level and volume. Some of

2553-415: A version of photosynthesis in the absence of oxygen with arsenites as electron donors , producing arsenates (just as ordinary photosynthesis uses water as electron donor, producing molecular oxygen). Researchers conjecture that, over the course of history, these photosynthesizing organisms produced the arsenates that allowed the arsenate-reducing bacteria to thrive. One strain , PHS-1, has been isolated and

2664-443: Is sag ponds . Volcanic lakes are lakes that occupy either local depressions, e.g. craters and maars , or larger basins, e.g. calderas , created by volcanism . Crater lakes are formed in volcanic craters and calderas, which fill up with precipitation more rapidly than they empty via either evaporation, groundwater discharge, or a combination of both. Sometimes the latter are called caldera lakes, although often no distinction

2775-403: Is a lake occupying a basin formed by surface dissolution of bedrock. In areas underlain by soluble bedrock, its solution by precipitation and percolating water commonly produce cavities. These cavities frequently collapse to form sinkholes that form part of the local karst topography . Where groundwater lies near the grounds surface, a sinkhole will be filled water as a solution lake. If such

2886-458: Is classified as a Group-A carcinogen . The three most common arsenic allotropes are grey, yellow, and black arsenic, with grey being the most common. Grey arsenic (α-As, space group R 3 m No. 166) adopts a double-layered structure consisting of many interlocked, ruffled, six-membered rings. Because of weak bonding between the layers, grey arsenic is brittle and has a relatively low Mohs hardness of 3.5. Nearest and next-nearest neighbors form

2997-468: Is dammed behind an ice shelf that is attached to the coastline. They are mostly found in Antarctica. Fluvial (or riverine) lakes are lakes produced by running water. These lakes include plunge pool lakes , fluviatile dams and meander lakes. The most common type of fluvial lake is a crescent-shaped lake called an oxbow lake due to the distinctive curved shape. They can form in river valleys as

3108-606: Is estimated that approximately 57 million people in the Bengal basin are drinking groundwater with arsenic concentrations elevated above the World Health Organization 's standard of 10 parts per billion (ppb). However, a study of cancer rates in Taiwan suggested that significant increases in cancer mortality appear only at levels above 150 ppb. The arsenic in the groundwater is of natural origin, and

3219-514: Is genuinely tribasic, with the formula As(OH) 3 . A broad variety of sulfur compounds of arsenic are known. Orpiment ( As 2 S 3 ) and realgar ( As 4 S 4 ) are somewhat abundant and were formerly used as painting pigments. In As 4 S 10 , arsenic has a formal oxidation state of +2 in As 4 S 4 which features As-As bonds so that the total covalency of As is still 3. Both orpiment and realgar, as well as As 4 S 3 , have selenium analogs;

3330-589: Is in alloying with lead. Lead components in car batteries are strengthened by the presence of a very small percentage of arsenic. Dezincification of brass (a copper-zinc alloy) is greatly reduced by the addition of arsenic. "Phosphorus Deoxidized Arsenical Copper" with an arsenic content of 0.3% has an increased corrosion stability in certain environments. Gallium arsenide is an important semiconductor material, used in integrated circuits . Circuits made from GaAs are much faster (but also much more expensive) than those made from silicon . Unlike silicon, GaAs has

3441-647: Is inhalation of atmospheric gases and dusts. During the Victorian era , arsenic was widely used in home decor, especially wallpapers. In Europe, an analysis based on 20,000 soil samples across all 28 countries show that 98% of sampled soils have concentrations less than 20 mg kg-1. In addition, the As hotspots are related to frequent fertilization and close distance to mining activities. Extensive arsenic contamination of groundwater has led to widespread arsenic poisoning in Bangladesh and neighboring countries. It

Little Blue Run Lake - Misplaced Pages Continue

3552-427: Is little danger in eating fish because this arsenic compound is nearly non-toxic. Naturally occurring sources of human exposure include volcanic ash , weathering of minerals and ores, and mineralized groundwater. Arsenic is also found in food, water, soil, and air. Arsenic is absorbed by all plants, but is more concentrated in leafy vegetables, rice, apple and grape juice, and seafood. An additional route of exposure

3663-452: Is made. An example is Crater Lake in Oregon , in the caldera of Mount Mazama . The caldera was created in a massive volcanic eruption that led to the subsidence of Mount Mazama around 4860 BCE. Other volcanic lakes are created when either rivers or streams are dammed by lava flows or volcanic lahars . The basin which is now Malheur Lake , Oregon was created when a lava flow dammed

3774-433: Is recovered primarily from copper refinement dust. On roasting arsenopyrite in air, arsenic sublimes as arsenic(III) oxide leaving iron oxides, while roasting without air results in the production of gray arsenic. Further purification from sulfur and other chalcogens is achieved by sublimation in vacuum, in a hydrogen atmosphere, or by distillation from molten lead-arsenic mixture. The word arsenic has its origin in

3885-561: Is related to the gammaproteobacterium Ectothiorhodospira shaposhnikovii . The mechanism is unknown, but an encoded Arr enzyme may function in reverse to its known homologues . In 2011, it was postulated that the Halomonadaceae strain GFAJ-1 could be grown in the absence of phosphorus if that element were substituted with arsenic, exploiting the fact that the arsenate and phosphate anions are similar structurally. The study

3996-467: Is released from the sediment into the groundwater, caused by the anoxic conditions of the subsurface. This groundwater was used after local and western NGOs and the Bangladeshi government undertook a massive shallow tube well drinking-water program in the late twentieth century. This program was designed to prevent drinking of bacteria-contaminated surface waters, but failed to test for arsenic in

4107-474: Is resistant to all-trans retinoic acid . A 2008 paper reports success in locating tumors using arsenic-74 (a positron emitter). This isotope produces clearer PET scan images than the previous radioactive agent, iodine -124, because the body tends to transport iodine to the thyroid gland producing signal noise. Nanoparticles of arsenic have shown ability to kill cancer cells with lesser cytotoxicity than other arsenic formulations. The main use of arsenic

4218-494: Is stable only below −50 °C, at which temperature it decomposes to the trichloride, releasing chlorine gas. ) Arsenic is used as the group 5 element in the III-V semiconductors gallium arsenide , indium arsenide , and aluminium arsenide . The valence electron count of GaAs is the same as a pair of Si atoms, but the band structure is completely different which results in distinct bulk properties. Other arsenic alloys include

4329-490: Is the 22nd most abundant element in seawater and ranks 41st in abundance in the universe. Minerals with the formula MAsS and MAs 2 (M = Fe , Ni , Co ) are the dominant commercial sources of arsenic, together with realgar (an arsenic sulfide mineral) and native (elemental) arsenic. An illustrative mineral is arsenopyrite ( Fe As S ), which is structurally related to iron pyrite . Many minor As-containing minerals are known. Arsenic also occurs in various organic forms in

4440-485: Is therefore called a monoisotopic element . As of 2024, at least 32 radioisotopes have also been synthesized, ranging in atomic mass from 64 to 95. The most stable of these is As with a half-life of 80.30 days. All other isotopes have half-lives of under one day, with the exception of As ( t 1/2 =65.30 hours), As ( t 1/2 =26.0 hours), As ( t 1/2 =17.77 days), As ( t 1/2 =26.26 hours), and As ( t 1/2 =38.83 hours). Isotopes that are lighter than

4551-496: Is typically pyramidal owing to the influence of the lone pair of electrons . One of the simplest arsenic compounds is the trihydride, the highly toxic, flammable, pyrophoric arsine (AsH 3 ). This compound is generally regarded as stable, since at room temperature it decomposes only slowly. At temperatures of 250–300 °C decomposition to arsenic and hydrogen is rapid. Several factors, such as humidity , presence of light and certain catalysts (namely aluminium) facilitate

Little Blue Run Lake - Misplaced Pages Continue

4662-429: Is unknown but is estimated to be at least 2 million. Finland has 168,000 lakes of 500 square metres (5,400 sq ft) in area, or larger, of which 57,000 are large (10,000 square metres (110,000 sq ft) or larger). Most lakes have at least one natural outflow in the form of a river or stream , which maintain a lake's average level by allowing the drainage of excess water. Some lakes do not have

4773-496: Is unlined and has over time leaked pollution into the local ground and surface water, which local families rely on for consumption, cooking, and bathing. Some local residents worry for their health because of this pollution. In addition to the water concerns, families living near the site worry about toxic dust and complain of a strong rotten egg smell from hydrogen sulfide ( H 2 S ). Numerous lawsuits regarding Little Blue Run Lake have been filed against FirstEnergy. In one action,

4884-455: Is used to detect precise levels of intracellular arsenic and other arsenic bases involved in epigenetic modification of DNA. Studies investigating arsenic as an epigenetic factor can be used to develop precise biomarkers of exposure and susceptibility. The Chinese brake fern ( Pteris vittata ) hyperaccumulates arsenic from the soil into its leaves and has a proposed use in phytoremediation . Inorganic arsenic and its compounds, upon entering

4995-759: The Malheur River . Among all lake types, volcanic crater lakes most closely approximate a circular shape. Glacial lakes are lakes created by the direct action of glaciers and continental ice sheets. A wide variety of glacial processes create enclosed basins. As a result, there are a wide variety of different types of glacial lakes and it is often difficult to define clear-cut distinctions between different types of glacial lakes and lakes influenced by other activities. The general types of glacial lakes that have been recognized are lakes in direct contact with ice, glacially carved rock basins and depressions, morainic and outwash lakes, and glacial drift basins. Glacial lakes are

5106-509: The Ohio River , which is the drinking water source for more than three million people. The Pennsylvania Department of Environmental Protection (PADEP) estimates that if the dam failed it would affect 50,000 people and has mandated that coal ash cannot be added to the lake after 2016. In 2015, Vice News reported that dangerous pollutants were leaking from the body of water into the local community. The Little Blue Run Coal Ash Impoundment

5217-554: The Proto-Indo-European root * leǵ- ('to leak, drain'). Cognates include Dutch laak ('lake, pond, ditch'), Middle Low German lāke ('water pooled in a riverbed, puddle') as in: de:Wolfslake , de:Butterlake , German Lache ('pool, puddle'), and Icelandic lækur ('slow flowing stream'). Also related are the English words leak and leach . There is considerable uncertainty about defining

5328-712: The Renaissance era . During the Bronze Age , arsenic was melted with copper to make arsenical bronze . Jabir ibn Hayyan described the isolation of arsenic before 815 AD. Albertus Magnus (Albert the Great, 1193–1280) later isolated the element from a compound in 1250, by heating soap together with arsenic trisulfide . In 1649, Johann Schröder published two ways of preparing arsenic. Crystals of elemental (native) arsenic are found in nature, although rarely. Cadet's fuming liquid (impure cacodyl ), often claimed as

5439-539: The Syriac word ܙܪܢܝܟܐ zarnika , from Arabic al-zarnīḵ الزرنيخ 'the orpiment ', based on Persian zar ("gold") from the word زرنيخ zarnikh , meaning "yellow" (literally "gold-colored") and hence "(yellow) orpiment". It was adopted into Greek (using folk etymology ) as arsenikon ( ἀρσενικόν ) – a neuter form of the Greek adjective arsenikos ( ἀρσενικός ), meaning "male", "virile". Latin -speakers adopted

5550-631: The Vietnam War , the United States used Agent Blue , a mixture of sodium cacodylate and its acid form, as one of the rainbow herbicides to deprive North Vietnamese soldiers of foliage cover and rice. Some species of bacteria obtain their energy in the absence of oxygen by oxidizing various fuels while reducing arsenate to arsenite. Under oxidative environmental conditions some bacteria use arsenite as fuel, which they oxidize to arsenate. The enzymes involved are known as arsenate reductases (Arr). In 2008, bacteria were discovered that employ

5661-399: The density of water varies with temperature, with a maximum at +4 degrees Celsius, thermal stratification is an important physical characteristic of a lake that controls the fauna and flora , sedimentation, chemistry, and other aspects of individual lakes. First, the colder, denser water typically forms a layer near the bottom, which is called the hypolimnion . Second, normally overlying

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5772-490: The food chain , are progressively metabolized through a process of methylation . For example, the mold Scopulariopsis brevicaulis produces trimethylarsine if inorganic arsenic is present. The organic compound arsenobetaine is found in some marine foods such as fish and algae, and also in mushrooms in larger concentrations. The average person's intake is about 10–50 μg/day. Values about 1000 μg are not unusual following consumption of fish or mushrooms, but there

5883-457: The nonmetals . Though stable in dry air, arsenic forms a golden-bronze tarnish upon exposure to humidity which eventually becomes a black surface layer. When heated in air, arsenic oxidizes to arsenic trioxide ; the fumes from this reaction have an odor resembling garlic. This odor can be detected on striking arsenide minerals such as arsenopyrite with a hammer. It burns in oxygen to form arsenic trioxide and arsenic pentoxide , which have

5994-605: The ocean , although they may be connected with the ocean by rivers . Lakes, as with other bodies of water , are part of the water cycle , the processes by which water moves around the Earth. Most lakes are freshwater and account for almost all the world's surface freshwater, but some are salt lakes with salinities even higher than that of seawater . Lakes vary significantly in surface area and volume of water. Lakes are typically larger and deeper than ponds , which are also water-filled basins on land, although there are no official definitions or scientific criteria distinguishing

6105-542: The 20th century. A 2006 study of the remains of the Australian racehorse Phar Lap determined that its 1932 death was caused by a massive overdose of arsenic. Sydney veterinarian Percy Sykes stated, "In those days, arsenic was quite a common tonic, usually given in the form of a solution ( Fowler's Solution ) ... It was so common that I'd reckon 90 per cent of the horses had arsenic in their system." The toxicity of arsenic to insects, bacteria, and fungi led to its use as

6216-521: The As ion as the formation of such an anion would be highly endothermic and even the group 1 arsenides have properties of intermetallic compounds. Like germanium , selenium , and bromine , which like arsenic succeed the 3d transition series , arsenic is much less stable in the +5 oxidation state than its vertical neighbors phosphorus and antimony , and hence arsenic pentoxide and arsenic acid are potent oxidizers . Compounds of arsenic resemble, in some respects, those of phosphorus , which occupies

6327-597: The Earth by extraterrestrial objects (either meteorites or asteroids ). Examples of meteorite lakes are Lonar Lake in India, Lake El'gygytgyn in northeast Siberia, and the Pingualuit crater lake in Quebec, Canada. As in the cases of El'gygytgyn and Pingualuit, meteorite lakes can contain unique and scientifically valuable sedimentary deposits associated with long records of paleoclimatic changes. In addition to

6438-497: The Greek term as arsenicum , which in French ultimately became arsenic , whence the English word "arsenic". Arsenic sulfides (orpiment, realgar ) and oxides have been known and used since ancient times. Zosimos ( c.  300 AD ) describes roasting sandarach (realgar) to obtain cloud of arsenic ( arsenic trioxide ), which he then reduces to gray arsenic. As the symptoms of arsenic poisoning are not very specific,

6549-486: The II-V semiconductor cadmium arsenide . A large variety of organoarsenic compounds are known. Several were developed as chemical warfare agents during World War I, including vesicants such as lewisite and vomiting agents such as adamsite . Cacodylic acid , which is of historic and practical interest, arises from the methylation of arsenic trioxide, a reaction that has no analogy in phosphorus chemistry. Cacodyl

6660-576: The Little Blue Run Coal Ash Impoundment. The consent decree "The consent decree requires First Energy to submit a plan to close the plant by the end of 2016. The company will also have to pay a fine of $ 800,000, supply 21 households with hook-ups to municipal water systems, and conduct an environmental impact study on the area." FirstEnergy is required to clean up the site by 2031, but in April 2014, FirstEnergy agreed to have

6771-571: The Lusatian Lake District, Germany. In India, Sudarshana Lake is a historical artificial lake located in the semi-arid region of Girnar, Gujarat, originally constructed during the reign of Chandragupta Maurya. See: List of notable artificial lakes in the United States Meteorite lakes, also known as crater lakes (not to be confused with volcanic crater lakes ), are created by catastrophic impacts with

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6882-572: The Pennsylvania residents, a minority of the parties who claim to have been affected, was settled out of court in February 2015. The terms of the settlement were undisclosed. Artificial lake A lake is an often naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land . Lakes lie completely on land and are separate from

6993-430: The United States by 2013 in all agricultural activities except cotton farming. The biogeochemistry of arsenic is complex and includes various adsorption and desorption processes. The toxicity of arsenic is connected to its solubility and is affected by pH. Arsenite ( AsO 3− 3 ) is more soluble than arsenate ( AsO 3− 4 ) and is more toxic; however, at a lower pH, arsenate becomes more mobile and toxic. It

7104-438: The analogous As 2 Te 3 is known as the mineral kalgoorlieite , and the anion As 2 Te is known as a ligand in cobalt complexes. All trihalides of arsenic(III) are well known except the astatide, which is unknown. Arsenic pentafluoride (AsF 5 ) is the only important pentahalide, reflecting the lower stability of the +5 oxidation state; even so, it is a very strong fluorinating and oxidizing agent. (The pentachloride

7215-866: The base of the valley has remained in place for more than 100 years but the terrain below the lake is in danger of a catastrophic flood if the dam were to fail during a future earthquake. Tal-y-llyn Lake in north Wales is a landslide lake dating back to the last glaciation in Wales some 20000 years ago. Aeolian lakes are produced by wind action . These lakes are found mainly in arid environments, although some aeolian lakes are relict landforms indicative of arid paleoclimates . Aeolian lakes consist of lake basins dammed by wind-blown sand; interdunal lakes that lie between well-oriented sand dunes ; and deflation basins formed by wind action under previously arid paleoenvironments. Moses Lake in Washington , United States,

7326-915: The courses of mature rivers, where a river channel has widened over a basin formed by eroded floodplains and wetlands . Some lakes are found in caverns underground . Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ice age . All lakes are temporary over long periods of time , as they will slowly fill in with sediments or spill out of the basin containing them. Artificially controlled lakes are known as reservoirs , and are usually constructed for industrial or agricultural use, for hydroelectric power generation, for supplying domestic drinking water , for ecological or recreational purposes, or for other human activities. The word lake comes from Middle English lake ('lake, pond, waterway'), from Old English lacu ('pond, pool, stream'), from Proto-Germanic * lakō ('pond, ditch, slow moving stream'), from

7437-518: The creation of lakes by the disruption of preexisting drainage networks, it also creates within arid regions endorheic basins that contain salt lakes (also called saline lakes). They form where there is no natural outlet, a high evaporation rate and the drainage surface of the water table has a higher-than-normal salt content. Examples of these salt lakes include Great Salt Lake and the Dead Sea . Another type of tectonic lake caused by faulting

7548-622: The difference between lakes and ponds , and neither term has an internationally accepted definition across scientific disciplines or political boundaries. For example, limnologists have defined lakes as water bodies that are simply a larger version of a pond, which can have wave action on the shoreline or where wind-induced turbulence plays a major role in mixing the water column. None of these definitions completely excludes ponds and all are difficult to measure. For this reason, simple size-based definitions are increasingly used to separate ponds and lakes. Definitions for lake range in minimum sizes for

7659-620: The environment. In 2014, China was the top producer of white arsenic with almost 70% world share, followed by Morocco, Russia, and Belgium, according to the British Geological Survey and the United States Geological Survey . Most arsenic refinement operations in the US and Europe have closed over environmental concerns. Arsenic is found in the smelter dust from copper, gold, and lead smelters, and

7770-536: The exception of criterion 3, the others have been accepted or elaborated upon by other hydrology publications. The majority of lakes on Earth are freshwater , and most lie in the Northern Hemisphere at higher latitudes . Canada , with a deranged drainage system , has an estimated 31,752 lakes larger than 3 square kilometres (1.2 sq mi) in surface area. The total number of lakes in Canada

7881-591: The fields). The accidental use of arsenic in the adulteration of foodstuffs led to the Bradford sweet poisoning in 1858, which resulted in 21 deaths. From the late-18th century wallpaper production began to use dyes made from arsenic, which was thought to increase the pigment's brightness. One account of the illness and 1821 death of Napoleon I implicates arsenic poisoning involving wallpaper. Two arsenic pigments have been widely used since their discovery – Paris Green in 1814 and Scheele's Green in 1775. After

7992-399: The first synthetic organometallic compound , was synthesized in 1760 by Louis Claude Cadet de Gassicourt through the reaction of potassium acetate with arsenic trioxide . In the Victorian era , women would eat "arsenic" (" white arsenic " or arsenic trioxide) mixed with vinegar and chalk to improve the complexion of their faces, making their skin paler (to show they did not work in

8103-613: The groundwater. Many other countries and districts in Southeast Asia, such as Vietnam and Cambodia , have geological environments that produce groundwater with a high arsenic content. Arsenicosis was reported in Nakhon Si Thammarat , Thailand, in 1987, and the Chao Phraya River probably contains high levels of naturally occurring dissolved arsenic without being a public health problem because much of

8214-422: The hypolimnion is a transition zone known as the metalimnion . Finally, overlying the metalimnion is a surface layer of warmer water with a lower density, called the epilimnion . This typical stratification sequence can vary widely, depending on the specific lake or the time of year, or a combination of both. The classification of lakes by thermal stratification presupposes lakes with sufficient depth to form

8325-907: The intentional damming of rivers and streams, rerouting of water to inundate a previously dry basin , or the deliberate filling of abandoned excavation pits by either precipitation runoff , ground water , or a combination of both. Artificial lakes may be used as storage reservoirs that provide drinking water for nearby settlements , to generate hydroelectricity , for flood management , for supplying agriculture or aquaculture , or to provide an aquatic sanctuary for parks and nature reserves . The Upper Silesian region of southern Poland contains an anthropogenic lake district consisting of more than 4,000 water bodies created by human activity. The diverse origins of these lakes include: reservoirs retained by dams, flooded mines, water bodies formed in subsidence basins and hollows, levee ponds, and residual water bodies following river regulation. Same for

8436-471: The karst regions at the Dalmatian coast of Croatia and within large parts of Florida . A landslide lake is created by the blockage of a river valley by either mudflows , rockslides , or screes . Such lakes are most common in mountainous regions. Although landslide lakes may be large and quite deep, they are typically short-lived. An example of a landslide lake is Quake Lake , which formed as

8547-418: The lake level. Arsenic Arsenic is a chemical element with the symbol As and the atomic number 33. It is a metalloid and one of the pnictogens , and therefore shares many properties with its group 15 neighbors phosphorus and antimony . Arsenic is a notoriously toxic heavy metal . It occurs naturally in many minerals , usually in combination with sulfur and metals, but also as

8658-657: The largest lakes on Earth are rift lakes occupying rift valleys, e.g. Central African Rift lakes and Lake Baikal . Other well-known tectonic lakes, Caspian Sea , the Sea of Aral , and other lakes from the Pontocaspian occupy basins that have been separated from the sea by the tectonic uplift of the sea floor above the ocean level. Often, the tectonic action of crustal extension has created an alternating series of parallel grabens and horsts that form elongate basins alternating with mountain ranges. Not only does this promote

8769-528: The layers of sediment at the bottom of a meromictic lake remain relatively undisturbed, which allows for the development of lacustrine deposits . In a holomictic lake, the uniformity of temperature and density allows the lake waters to completely mix. Based upon thermal stratification and frequency of turnover, holomictic lakes are divided into amictic lakes , cold monomictic lakes , dimictic lakes , warm monomictic lakes, polymictic lakes , and oligomictic lakes. Lake stratification does not always result from

8880-560: The level of a lake are controlled by the difference between the input and output compared to the total volume of the lake. Significant input sources are precipitation onto the lake, runoff carried by streams and channels from the lake's catchment area, groundwater channels and aquifers, and artificial sources from outside the catchment area. Output sources are evaporation from the lake, surface and groundwater flows, and any extraction of lake water by humans. As climate conditions and human water requirements vary, these will create fluctuations in

8991-481: The mainland; lakes cut off from larger lakes by a bar; or lakes divided by the meeting of two spits. Organic lakes are lakes created by the actions of plants and animals. On the whole they are relatively rare in occurrence and quite small in size. In addition, they typically have ephemeral features relative to the other types of lakes. The basins in which organic lakes occur are associated with beaver dams, coral lakes, or dams formed by vegetation. Peat lakes are

9102-424: The mode of origin, lakes have been named and classified according to various other important factors such as thermal stratification , oxygen saturation, seasonal variations in lake volume and water level, salinity of the water mass, relative seasonal permanence, degree of outflow, and so on. The names used by the lay public and in the scientific community for different types of lakes are often informally derived from

9213-485: The moon Titan , which orbits the planet Saturn . The shape of lakes on Titan is very similar to those on Earth. Lakes were formerly present on the surface of Mars, but are now dry lake beds . In 1957, G. Evelyn Hutchinson published a monograph titled A Treatise on Limnology , which is regarded as a landmark discussion and classification of all major lake types, their origin, morphometric characteristics, and distribution. Hutchinson presented in his publication

9324-415: The morphology of the lakes' physical characteristics or other factors. Also, different cultures and regions of the world have their own popular nomenclature. One important method of lake classification is on the basis of thermal stratification, which has a major influence on the animal and plant life inhabiting a lake, and the fate and distribution of dissolved and suspended material in the lake. For example,

9435-406: The most numerous lakes in the world. Most lakes in northern Europe and North America have been either influenced or created by the latest, but not last, glaciation, to have covered the region. Glacial lakes include proglacial lakes , subglacial lakes , finger lakes , and epishelf lakes. Epishelf lakes are highly stratified lakes in which a layer of freshwater, derived from ice and snow melt,

9546-791: The names include: Lakes may be informally classified and named according to the general chemistry of their water mass. Using this classification method, the lake types include: A paleolake (also palaeolake ) is a lake that existed in the past when hydrological conditions were different. Quaternary paleolakes can often be identified on the basis of relict lacustrine landforms, such as relict lake plains and coastal landforms that form recognizable relict shorelines called paleoshorelines . Paleolakes can also be recognized by characteristic sedimentary deposits that accumulated in them and any fossils that might be contained in these sediments. The paleoshorelines and sedimentary deposits of paleolakes provide evidence for prehistoric hydrological changes during

9657-467: The nation's largest high hazard dams. Coal slurry from Bruce Mansfield Power Plant in Shippingport was piped into the lake. This same coal slurry is piped into the lake via a seven-mile long pipeline. The lake contains 20 billion US gallons (7.6 × 10 litres; 1.7 × 10 imperial gallons) of coal ash and smokestack scrubber waste. The northern coast of the lake is only a few hundred meters from

9768-562: The organic-rich deposits of pre-Quaternary paleolakes are important either for the thick deposits of oil shale and shale gas contained in them, or as source rocks of petroleum and natural gas . Although of significantly less economic importance, strata deposited along the shore of paleolakes sometimes contain coal seams . Lakes have numerous features in addition to lake type, such as drainage basin (also known as catchment area), inflow and outflow, nutrient content, dissolved oxygen , pollutants , pH , and sedimentation . Changes in

9879-408: The presence of mercury vapors. It is glassy and brittle. Black arsenic is also a poor electrical conductor. Arsenic sublimes upon heating at atmospheric pressure , converting directly to a gaseous form without an intervening liquid state at 887 K (614 °C). The triple point is at 3.63 MPa and 1,090 K (820 °C). Arsenic occurs in nature as one stable isotope , As, and

9990-938: The public uses bottled water . In Pakistan, more than 60 million people are exposed to arsenic polluted drinking water indicated by a 2017 report in Science . Podgorski's team investigated more than 1200 samples and more than 66% exceeded the WHO minimum contamination level. Since the 1980s, residents of the Ba Men region of Inner Mongolia, China have been chronically exposed to arsenic through drinking water from contaminated wells. A 2009 research study observed an elevated presence of skin lesions among residents with well water arsenic concentrations between 5 and 10 μg/L, suggesting that arsenic induced toxicity may occur at relatively low concentrations with chronic exposure. Overall, 20 of China's 34 provinces have high arsenic concentrations in

10101-444: The rate of decomposition. It oxidises readily in air to form arsenic trioxide and water, and analogous reactions take place with sulfur and selenium instead of oxygen . Arsenic forms colorless, odorless, crystalline oxides As 2 O 3 (" white arsenic ") and As 2 O 5 which are hygroscopic and readily soluble in water to form acidic solutions. Arsenic(V) acid is a weak acid and its salts, known as arsenates , are

10212-406: The same group (column) of the periodic table . The most common oxidation states for arsenic are: −3 in the arsenides , which are alloy-like intermetallic compounds, +3 in the arsenites , and +5 in the arsenates and most organoarsenic compounds. Arsenic also bonds readily to itself as seen in the square As 3− 4 ions in the mineral skutterudite . In the +3 oxidation state , arsenic

10323-443: The same structure as the more well-known phosphorus compounds, and in fluorine to give arsenic pentafluoride . Arsenic makes arsenic acid with concentrated nitric acid , arsenous acid with dilute nitric acid, and arsenic trioxide with concentrated sulfuric acid ; however, it does not react with water, alkalis, or non-oxidising acids. Arsenic reacts with metals to form arsenides , though these are not ionic compounds containing

10434-746: The site "for as long as environmental problems remain at the site." As a result of settling the lawsuit, FirstEnergy began disposing the byproduct (through the process of dewatering ) in a lined impoundment at Murray Energy 's mine in Marshall County, West Virginia . Another lawsuit was filed in Federal Court by 15 Beaver County, Pennsylvania residents and 36 West Virginia residents who accused FirstEnergy of contaminating groundwater and leaking hazardous waste, including arsenic , sulfates , sodium , calcium , magnesium and chloride into local waterways and groundwater systems. The dispute with

10545-425: The site cleaned by 2028. FirstEnergy is required to cover the ash with two layers of impermeable "geotextile" sheeting to keep unhealthy chemicals from entering the local groundwater, it must monitor noise, odors and particulate emissions, conduct quarterly reconnaissance of contaminated water seepage from the lake and take corrective actions when necessary. According to the PADEP, FirstEnergy is also required to monitor

10656-476: The stable As tend to decay by β decay , and those that are heavier tend to decay by β decay , with some exceptions. At least 10 nuclear isomers have been described, ranging in atomic mass from 66 to 84. The most stable of arsenic's isomers is As with a half-life of 111 seconds. Arsenic has a similar electronegativity and ionization energies to its lighter pnictogen congener phosphorus and therefore readily forms covalent molecules with most of

10767-575: The substance was frequently used for murder until the advent in the 1830s of the Marsh test , a sensitive chemical test for its presence. (Another less sensitive but more general test is the Reinsch test .) Owing to its use by the ruling class to murder one another and its potency and discreetness, arsenic has been called the "poison of kings" and the "king of poisons". Arsenic became known as "the inheritance powder" due to its use in killing family members in

10878-404: The thermal stratification, as well as the degree and frequency of mixing, has a strong control over the distribution of oxygen within the lake. Professor F.-A. Forel , also referred to as the "Father of limnology", was the first scientist to classify lakes according to their thermal stratification. His system of classification was later modified and improved upon by Hutchinson and Löffler. As

10989-456: The times that they existed. There are two types of paleolake: Paleolakes are of scientific and economic importance. For example, Quaternary paleolakes in semidesert basins are important for two reasons: they played an extremely significant, if transient, role in shaping the floors and piedmonts of many basins; and their sediments contain enormous quantities of geologic and paleontologic information concerning past environments. In addition,

11100-456: The toxicity of arsenic became widely known, these chemicals were used less often as pigments and more often as insecticides. In the 1860s, an arsenic byproduct of dye production, London Purple, was widely used. This was a solid mixture of arsenic trioxide, aniline, lime, and ferrous oxide, insoluble in water and very toxic by inhalation or ingestion But it was later replaced with Paris Green , another arsenic-based dye. With better understanding of

11211-451: The toxicology mechanism, two other compounds were used starting in the 1890s. Arsenite of lime and arsenate of lead were used widely as insecticides until the discovery of DDT in 1942. In small doses, soluble arsenic compounds act as stimulants , and were once popular as medicine by people in the mid-18th to 19th centuries; this use was especially prevalent for sport animals such as race horses or work dogs and continued into

11322-609: The trioxide, are used in the production of pesticides , treated wood products, herbicides , and insecticides . These applications are declining with the increasing recognition of the toxicity of arsenic and its compounds. Arsenic has been known since ancient times to be poisonous to humans. However, a few species of bacteria are able to use arsenic compounds as respiratory metabolites . Trace quantities of arsenic have been proposed to be an essential dietary element in rats, hamsters, goats, and chickens. Research has not been conducted to determine whether small amounts of arsenic may play

11433-641: The two. Lakes are also distinct from lagoons , which are generally shallow tidal pools dammed by sandbars or other material at coastal regions of oceans or large lakes. Most lakes are fed by springs , and both fed and drained by creeks and rivers , but some lakes are endorheic without any outflow, while volcanic lakes are filled directly by precipitation runoffs and do not have any inflow streams. Natural lakes are generally found in mountainous areas (i.e. alpine lakes ), dormant volcanic craters , rift zones and areas with ongoing glaciation . Other lakes are found in depressed landforms or along

11544-405: The waste in the lake is prevented from escaping thanks to a 400-foot (120 m) tall, 2,200-foot (670 m) wide rock-and-earth dam . The dam containing Little Blue Run Lake has been given a designation of "high hazard", meaning, there would be harm or loss of life if the structure were to fail. Some of the natural valleys in the area were filled with a coal ash slurry and held in place by one of

11655-467: The word pond , and a lesser number of names ending with lake are, in quasi-technical fact, ponds. One textbook illustrates this point with the following: "In Newfoundland, for example, almost every lake is called a pond, whereas in Wisconsin, almost every pond is called a lake." One hydrology book proposes to define the term "lake" as a body of water with the following five characteristics: With

11766-489: Was also used in various agricultural insecticides and poisons. For example, lead hydrogen arsenate was a common insecticide on fruit trees , but contact with the compound sometimes resulted in brain damage among those working the sprayers. In the second half of the 20th century, monosodium methyl arsenate (MSMA) and disodium methyl arsenate (DSMA) – less toxic organic forms of arsenic – replaced lead arsenate in agriculture. These organic arsenicals were in turn phased out in

11877-451: Was found that addition of sulfur, phosphorus, and iron oxides to high-arsenite soils greatly reduces arsenic phytotoxicity. Arsenic is used as a feed additive in poultry and swine production , in particular it was used in the U.S. until 2015 to increase weight gain, improve feed efficiency , and prevent disease. An example is roxarsone , which had been used as a broiler starter by about 70% of U.S. broiler growers. In 2011, Alpharma,

11988-495: Was indicated for syphilis , but has been superseded by modern antibiotics . However, arsenicals such as melarsoprol are still used for the treatment of trypanosomiasis , since although these drugs have the disadvantage of severe toxicity, the disease is almost uniformly fatal if untreated. In 2000 the US Food and Drug Administration approved arsenic trioxide for the treatment of patients with acute promyelocytic leukemia that

12099-617: Was originally a shallow natural lake and an example of a lake basin dammed by wind-blown sand. China's Badain Jaran Desert is a unique landscape of megadunes and elongated interdunal aeolian lakes, particularly concentrated in the southeastern margin of the desert. Shoreline lakes are generally lakes created by blockage of estuaries or by the uneven accretion of beach ridges by longshore and other currents. They include maritime coastal lakes, ordinarily in drowned estuaries; lakes enclosed by two tombolos or spits connecting an island to

12210-583: Was the first organometallic compound known (even though arsenic is not a true metal) and was named from the Greek κακωδία "stink" for its offensive, garlic-like odor; it is very toxic. Arsenic is the 53rd most abundant element in the Earth's crust , comprising about 1.5  parts per million  (0.00015%). Typical background concentrations of arsenic do not exceed 3 ng/m in the atmosphere; 100 mg/kg in soil; 400 μg/kg in vegetation; 10 μg/L in freshwater and 1.5 μg/L in seawater. Arsenic

12321-1020: Was widely criticised and subsequently refuted by independent researcher groups. Arsenic may be an essential trace mineral in birds, involved in the synthesis of methionine metabolites, with feeding recommendations being between 0.012 and 0.050 mg/kg. Some evidence indicates that arsenic is an essential trace mineral in mammals. However, the biological function is not known. Arsenic has been linked to epigenetic changes , heritable changes in gene expression that occur without changes in DNA sequence . These include DNA methylation, histone modification, and RNA interference. Toxic levels of arsenic cause significant DNA hypermethylation of tumor suppressor genes p16 and p53 , thus increasing risk of carcinogenesis . These epigenetic events have been studied in vitro using human kidney cells and in vivo using rat liver cells and peripheral blood leukocytes in humans. Inductively coupled plasma mass spectrometry (ICP-MS)

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