The Quecreek Mine rescue took place in Somerset County, Pennsylvania , when nine miners were trapped underground for over 77 hours, from July 24 to 28, 2002. All nine miners were rescued.
157-616: On July 24, eighteen coal miners at the Quecreek Mine ( / k juː . k r i k / ) in Lincoln Township , Somerset County, Pennsylvania, owned by Black Wolf Coal Company, accidentally dug into the abandoned, poorly documented Saxman Coal / Harrison #2 Mine, flooding the room and pillar mine with an estimated 75 million US gallons (280,000 cubic metres) of water. Both the Saxman Mine and Quecreek Mine are in
314-583: A cascade method, Swiss chemist and physicist Raoul Pierre Pictet evaporated liquid sulfur dioxide in order to liquefy carbon dioxide, which in turn was evaporated to cool oxygen gas enough to liquefy it. He sent a telegram on December 22, 1877, to the French Academy of Sciences in Paris announcing his discovery of liquid oxygen . Just two days later, French physicist Louis Paul Cailletet announced his own method of liquefying molecular oxygen. Only
471-683: A coal preparation plant . Technical and economic feasibility are evaluated based on the following: regional geological conditions; overburden characteristics; coal seam continuity, thickness, structure, quality, and depth; strength of materials above and below the seam for roof and floor conditions; topography, especially altitude and slope; climate; land ownership as it affects the availability of land for mining and access; surface drainage patterns; groundwater conditions; availability of labor and materials; coal purchaser requirements in terms of tonnage, quality, and destination; and capital investment requirements. Surface mining and deep underground mining are
628-705: A 70% increase over the 20 years since 1999. In 2018, the world production of brown coal (lignite) was 803.2 Mt, with Germany the world's largest producer at 166.3 Mt. China is most likely the second largest producer and consumer of lignite globally although specific lignite production data is not made available. Coal production has grown fastest in Asia, while Europe has declined. Since 2011, world coal production has been stable, with decreases in Europe and US offset by increases from China, Indonesia and Australia. The top coal mining nations are: Energy production from coal mining
785-477: A chemical element. The name oxygen was coined in 1777 by Antoine Lavoisier , who first recognized oxygen as a chemical element and correctly characterized the role it plays in combustion. Common industrial uses of oxygen include production of steel , plastics and textiles , brazing, welding and cutting of steels and other metals , rocket propellant , oxygen therapy , and life support systems in aircraft , submarines , spaceflight and diving . One of
942-440: A coal mine and its structures are a colliery , a coal mine is called a "pit", and above-ground mining structures are referred to as a " pit head ". In Australia , "colliery" generally refers to an underground coal mine. Coal mining has had many developments in recent years, from the early days of men tunneling, digging, and manually extracting the coal on carts to large open-cut and longwall mines. Mining at this scale requires
1099-467: A coal seam occurring near the top of a ridge or hill, the entire top is removed in a series of parallel cuts. Overburden is deposited in nearby valleys and hollows. This method usually leaves the ridge and hilltops as flattened plateaus. The process is highly controversial for the drastic changes in topography, the practice of creating head-of-hollow-fills , or filling in valleys with mining debris, and for covering streams and disrupting ecosystems. Spoil
1256-464: A decision was made to change to a 26-inch (660 mm) bit since there was one available 7 miles (11 km) south of the mine in Somerset, and it would accommodate the rescue capsule. At 6:30 a.m. the installation of the new 26-inch bit was completed and drilling resumed. One possibility that was feared at this point was that of breaking into the chamber too quickly, resulting in the water in
1413-601: A drill that could bore a hole big enough to raise men from a mine. One was located in Clarksburg, West Virginia . Water continued to rise in the mine during the morning hours of Thursday, July 25. During this time period, water levels rose to the portal entrance (by means inward from mine entrance portal), as follows: With the mine portal entrances to Quecreek mine nearly under water, rescue operations started immediately. While pumping water would begin at all mine locations and any nearby residential and commercial water wells,
1570-434: A few drops of the liquid were produced in each case and no meaningful analysis could be conducted. Oxygen was liquefied in a stable state for the first time on March 29, 1883, by Polish scientists from Jagiellonian University , Zygmunt Wróblewski and Karol Olszewski . In 1891 Scottish chemist James Dewar was able to produce enough liquid oxygen for study. The first commercially viable process for producing liquid oxygen
1727-403: A greater proportion of the coal deposit than underground methods, as more of the coal seams in the strata may be exploited. This equipment can include the following: Draglines which operate by removing the overburden, power shovels, large trucks in which transport overburden and coal, bucket wheel excavators, and conveyors. In this mining method, explosives are first used in order to break through
SECTION 10
#17327979865291884-481: A higher amount of energy per unit mass, specific energy or massic energy, and can often be obtained in areas where wood is not readily available. Though it was used historically as a domestic fuel, coal is now used mostly in industry, especially in smelting and alloy production, as well as electricity generation . Large-scale coal mining developed during the Industrial Revolution , and coal provided
2041-440: A land use condition is not equal to the original use. Existing land uses (such as livestock grazing, crop and timber production) are temporarily eliminated in mining areas. High-value, intensive-land-use areas like urban and transportation systems are not usually affected by mining operations. If mineral values are sufficient, these improvements may be removed to an adjacent area. Strip mining eliminates existing vegetation, destroys
2198-440: A large dining-room table, but with hydraulic jacks for legs. After the large pillars of coal have been mined away, the mobile roof support's legs shorten and it is withdrawn to a safe area. The mine roof typically collapses once the mobile roof supports leave an area. There are six principal methods of underground mining: Coal is mined commercially in over 50 countries. 7,921 million metric tons (Mt) of coal were produced in 2019,
2355-481: A light sky-blue color caused by absorption in the red (in contrast with the blue color of the sky, which is due to Rayleigh scattering of blue light). High-purity liquid O 2 is usually obtained by the fractional distillation of liquefied air. Liquid oxygen may also be condensed from air using liquid nitrogen as a coolant. Liquid oxygen is a highly reactive substance and must be segregated from combustible materials. The spectroscopy of molecular oxygen
2512-564: A major role in absorbing energy from singlet oxygen and converting it to the unexcited ground state before it can cause harm to tissues. The common allotrope of elemental oxygen on Earth is called dioxygen , O 2 , the major part of the Earth's atmospheric oxygen (see Occurrence ). O 2 has a bond length of 121 pm and a bond energy of 498 kJ/mol . O 2 is used by complex forms of life, such as animals, in cellular respiration . Other aspects of O 2 are covered in
2669-447: A method that currently accounts for about 60 percent of world coal production. In deep mining, the room and pillar or bord and pillar method progresses along the seam, while pillars and timber are left standing to support the mine roof. Once room and pillar mines have been developed to a stopping point limited by geology, ventilation, or economics, a supplementary version of room and pillar mining, termed second mining or retreat mining ,
2826-429: A new coal mine. Oxygen Oxygen is a chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table , a highly reactive nonmetal , and a potent oxidizing agent that readily forms oxides with most elements as well as with other compounds . Oxygen is the most abundant element in Earth's crust , and the third-most abundant element in
2983-438: A part of air that he called spiritus nitroaereus . In one experiment, he found that placing either a mouse or a lit candle in a closed container over water caused the water to rise and replace one-fourteenth of the air's volume before extinguishing the subjects. From this, he surmised that nitroaereus is consumed in both respiration and combustion. Mayow observed that antimony increased in weight when heated, and inferred that
3140-485: A portion of the bit was retrieved from the hole, but it was discovered that part of the bit had broken off and remained stuck in the hole. A special tool needed to be fabricated in order to assist in retrieving the bit. Normally, such a job would be done in three or four days, but a 95-member machine shop in Big Run, Jefferson County , was able to build the tool in approximately three hours. A National Guard helicopter flew
3297-499: A press conference scheduled to occur later that night. State Police Cpl. Robert Barnes Jr. also telephoned families of missing miners asking them to come to the Sipesville firehouse for more information. Around 11 p.m., Barnes also asked a local United Methodist pastor, Barry Ritenour, if he could spend the night at the firehouse with the families. In addition, calls were made between 11:30 p.m. and 12 a.m. to find
SECTION 20
#17327979865293454-404: A process called eutrophication and the decay of these organisms and other biomaterials may reduce the O 2 content in eutrophic water bodies. Scientists assess this aspect of water quality by measuring the water's biochemical oxygen demand , or the amount of O 2 needed to restore it to a normal concentration. Paleoclimatologists measure the ratio of oxygen-18 and oxygen-16 in
3611-589: A result of occupational exposures is coined occupational hearing loss . To protect miners' hearing, the US Mine Safety and Health Administration 's (MSHA) guidelines for noise place a Permissible Exposure Limit (PEL) for noise at 90 dBA time-weighted over 8 hours. A lower cutoff, 85 dBA, is set for a worker to fall into the MSHA Action Level which dictates that workers be placed into hearing conservation programs. Noise exposures vary depending on
3768-458: A small proportion of manganese dioxide. Oxygen levels in the atmosphere are trending slightly downward globally, possibly because of fossil-fuel burning. At standard temperature and pressure , oxygen is a colorless, odorless, and tasteless gas with the molecular formula O 2 , referred to as dioxygen. As dioxygen , two oxygen atoms are chemically bound to each other. The bond can be variously described based on level of theory, but
3925-485: A surface (also called an open cast) mine. Additionally, coal seam thickness and geology are factors in the selection of a mining method. The most economical method of coal extraction for surface mines is the electric shovel or drag line. The most economical form of underground mining is the long wall, which involves using two spinning drums with carbide bits that runs along sections of the coal seam. Many coals extracted from both surface and underground mines require washing in
4082-421: A temperature of 197 °F (92 °C) at 90 pounds per square inch (620 kPa). The sound due to the high rate of pumped air deafened and hurt the miner's ears, but provided hope by the knowledge that rescuers knew where they were. Meanwhile, an ongoing battle was to dewater the Quecreek Mine to allow rescue operations to be planned. Millions of gallons of water had to be pumped from the flooded coal mines as
4239-449: A triplet electronic ground state . An electron configuration with two unpaired electrons, as is found in dioxygen orbitals (see the filled π* orbitals in the diagram) that are of equal energy—i.e., degenerate —is a configuration termed a spin triplet state. Hence, the ground state of the O 2 molecule is referred to as triplet oxygen . The highest-energy, partially filled orbitals are antibonding , and so their filling weakens
4396-580: Is a corrosive byproduct of smog and thus an air pollutant . Oxygen was isolated by Michael Sendivogius before 1604, but it is commonly believed that the element was discovered independently by Carl Wilhelm Scheele , in Uppsala , in 1773 or earlier, and Joseph Priestley in Wiltshire , in 1774. Priority is often given for Priestley because his work was published first. Priestley, however, called oxygen "dephlogisticated air", and did not recognize it as
4553-477: Is absorbed by specialized respiratory organs called gills , through the skin or via the gut ; in terrestrial animals such as tetrapods , oxygen in air is actively taken into the body via specialized organs known as lungs , where gas exchange takes place to diffuse oxygen into the blood and carbon dioxide out, and the body's circulatory system then transports the oxygen to other tissues where cellular respiration takes place. However in insects ,
4710-575: Is accomplished by drilling holes into the overburden, filling the holes with explosives, and detonating the explosive. The overburden is then removed, using large earth-moving equipment, such as draglines , shovel and trucks, excavator and trucks, or bucket-wheels and conveyors. This overburden is put into the previously mined (and now empty) strip. When all the overburden is removed, the underlying coal seam will be exposed (a 'block' of coal). This block of coal may be drilled and blasted (if hard) or otherwise loaded onto trucks or conveyors for transport to
4867-513: Is associated with the atmospheric processes of aurora and airglow . The absorption in the Herzberg continuum and Schumann–Runge bands in the ultraviolet produces atomic oxygen that is important in the chemistry of the middle atmosphere. Excited-state singlet molecular oxygen is responsible for red chemiluminescence in solution. Table of thermal and physical properties of oxygen (O 2 ) at atmospheric pressure: Naturally occurring oxygen
Quecreek Mine rescue - Misplaced Pages Continue
5024-427: Is commonly started. Miners remove the coal in the pillars, thereby recovering as much coal from the coal seam as possible. A work area involved in pillar extraction is called a pillar section. Modern pillar sections use remote-controlled equipment, including large hydraulic mobile roof-supports, which can prevent cave-ins until the miners and their equipment have left a work area. The mobile roof supports are similar to
5181-472: Is composed of three stable isotopes , O , O , and O , with O being the most abundant (99.762% natural abundance ). Most O is synthesized at the end of the helium fusion process in massive stars but some is made in the neon burning process . O is primarily made by the burning of hydrogen into helium during the CNO cycle , making it a common isotope in the hydrogen burning zones of stars. Most O
5338-418: Is dedicated to mining activities until it can be reshaped and reclaimed. If mining is allowed, resident human populations must be resettled off the mine site; economic activities, such as agriculture or hunting and gathering food and medicinal plants are interrupted. What becomes of the land surface after mining is determined by the manner in which the mining is conducted. Usually reclamation of disturbed lands to
5495-516: Is highly concentrated in certain jurisdictions, which also concentrates much of the social and economic impacts of the industry to these regions. The industry directly employs over seven million workers worldwide, which, in turn, creates millions of indirect jobs. In several parts of the world, producers have reached peak coal as some economies shift away from fossil fuels to address climate change. A 2020 study found that renewables jobs could feasibly be created in these geographies to replace many of
5652-484: Is mostly used to generate electricity, and 75% of annual coal production is exported, mostly to eastern Asia. In 2007, 428 million tonnes of coal was mined in Australia. In 2007, coal provided about 85% of Australia's electricity production. In the fiscal year 2008/09, 487 million tonnes of coal was mined, and 261 million tonnes was exported. In the fiscal year 2013/14, 430.9 million tonnes of coal
5809-447: Is oxygen as a component of water, the major constituent of lifeforms. Oxygen in Earth's atmosphere is produced by biotic photosynthesis , in which photon energy in sunlight is captured by chlorophyll to split water molecules and then react with carbon dioxide to produce carbohydrates and oxygen is released as a byproduct . Oxygen is too chemically reactive to remain a free element in air without being continuously replenished by
5966-417: Is partially economically recoverable. Coal refuse is distinct from the byproducts of burning coal, such as fly ash . Piles of coal refuse can have significant negative environmental consequences, including the leaching of iron, manganese, and aluminum residues into waterways and acid mine drainage . The runoff can create both surface and groundwater contamination. The piles also create a fire hazard, with
6123-593: Is placed at the head of a narrow, steep-sided valley or hollow. In preparation for filling this area, vegetation and soil are removed and a rock drain constructed down the middle of the area to be filled, where a natural drainage course previously existed. When the fill is completed, this underdrain will form a continuous water runoff system from the upper end of the valley to the lower end of the fill. Typical head-of-hollow fills are graded and terraced to create permanently stable slopes. Most coal seams are too deep underground for opencast mining and require underground mining,
6280-441: Is produced when N (made abundant from CNO burning) captures a He nucleus, making O common in the helium-rich zones of evolved, massive stars . Fifteen radioisotopes have been characterized, ranging from O to O. The most stable are O with a half-life of 122.24 seconds and O with a half-life of 70.606 seconds. All of the remaining radioactive isotopes have half-lives that are less than 27 seconds and
6437-408: Is reasonably and simply described as a covalent double bond that results from the filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atoms, the filling of which results in a bond order of two. More specifically, the double bond is the result of sequential, low-to-high energy, or Aufbau , filling of orbitals, and the resulting cancellation of contributions from
Quecreek Mine rescue - Misplaced Pages Continue
6594-436: Is referred to as 'overburden' and is removed in long strips. The overburden from the first strip is deposited in an area outside the planned mining area and referred to as out-of-pit dumping. Overburden from subsequent strips is deposited in the void left from mining the coal and overburden from the previous strip. This is referred to as in-pit dumping. It is often necessary to fragment the overburden by use of explosives. This
6751-515: Is removed and overburden dumped to the side. Dust, vibration, and diesel exhaust odors are created (affecting sight, sound, and smell). Residents of local communities often find such impacts disturbing or unpleasant. In case of mountaintop removal , tops are removed from mountains or hills to expose thick coal seams underneath. The soil and rock removed is deposited in nearby valleys, hollows and depressions, resulting in blocked (and contaminated) waterways. Removal of soil and rock overburden covering
6908-712: Is still common, with 4,000 new cases of black lung every year in the US (4 percent of workers annually) and 10,000 new cases every year in China (0.2 percent of workers). The use of water sprays in mining equipment reduces the risk to miners' lungs. Build-ups of a hazardous gas are known as damps, possibly from the German word Dampf which means steam or vapor: Noise is also a contributing factor to potential adverse effects on coal miners' health. Exposure to excessive noise can lead to noise-induced hearing loss . Hearing loss developed as
7065-712: Is temperature-dependent, and about twice as much ( 14.6 mg/L ) dissolves at 0 °C than at 20 °C ( 7.6 mg/L ). At 25 °C and 1 standard atmosphere (101.3 kPa ) of air, freshwater can dissolve about 6.04 milliliters (mL) of oxygen per liter , and seawater contains about 4.95 mL per liter. At 5 °C the solubility increases to 9.0 mL (50% more than at 25 °C) per liter for freshwater and 7.2 mL (45% more) per liter for sea water. Oxygen condenses at 90.20 K (−182.95 °C, −297.31 °F) and freezes at 54.36 K (−218.79 °C, −361.82 °F). Both liquid and solid O 2 are clear substances with
7222-435: Is the result of the oxygen cycle . This biogeochemical cycle describes the movement of oxygen within and between its three main reservoirs on Earth: the atmosphere, the biosphere, and the lithosphere . The main driving factor of the oxygen cycle is photosynthesis , which is responsible for modern Earth's atmosphere. Photosynthesis releases oxygen into the atmosphere, while respiration , decay , and combustion remove it from
7379-463: Is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O 2 by volume) and Venus have much less. The O 2 surrounding those planets is produced solely by the action of ultraviolet radiation on oxygen-containing molecules such as carbon dioxide. The unusually high concentration of oxygen gas on Earth
7536-435: Is used for both thermal and metallurgical coals . In New South Wales open casting for steam coal and anthracite is practiced. Surface mining accounts for around 80 percent of production in Australia, while in the US it is used for about 67 percent of production. Globally, about 40 percent of coal production involves surface mining. Strip mining exposes coal by removing earth above each coal seam. This earth to be removed
7693-522: Is usually given priority in the discovery. The French chemist Antoine Laurent Lavoisier later claimed to have discovered the new substance independently. Priestley visited Lavoisier in October 1774 and told him about his experiment and how he liberated the new gas. Scheele had also dispatched a letter to Lavoisier on September 30, 1774, which described his discovery of the previously unknown substance, but Lavoisier never acknowledged receiving it (a copy of
7850-669: The Earth , the Moon , Mars , and meteorites , but were long unable to obtain reference values for the isotope ratios in the Sun , believed to be the same as those of the primordial solar nebula . Analysis of a silicon wafer exposed to the solar wind in space and returned by the crashed Genesis spacecraft has shown that the Sun has a higher proportion of oxygen-16 than does the Earth. The measurement implies that an unknown process depleted oxygen-16 from
8007-463: The Earth's crust in the form of various oxides such as water , carbon dioxide , iron oxides and silicates . All eukaryotic organisms , including plants , animals , fungi , algae and most protists , need oxygen for cellular respiration , which extracts chemical energy by the reaction of oxygen with organic molecules derived from food and releases carbon dioxide as a waste product. In aquatic animals , dissolved oxygen in water
SECTION 50
#17327979865298164-565: The Greek roots ὀξύς (oxys) ( acid , literally 'sharp', from the taste of acids) and -γενής (-genēs) (producer, literally begetter), because he mistakenly believed that oxygen was a constituent of all acids. Chemists (such as Sir Humphry Davy in 1812) eventually determined that Lavoisier was wrong in this regard, but by then the name was too well established. Oxygen entered the English language despite opposition by English scientists and
8321-503: The global energy economy . The major coal producing countries, though, such as China , Indonesia, India and Australia , have not reached peak production, with production increases replacing falls in Europe and the United States and proposed mines under development. The coal mining industry employs almost 2.7 million workers. The History of coal mining goes back thousands of years, with early mines documented in ancient China,
8478-470: The shells and skeletons of marine organisms to determine the climate millions of years ago (see oxygen isotope ratio cycle ). Seawater molecules that contain the lighter isotope , oxygen-16, evaporate at a slightly faster rate than water molecules containing the 12% heavier oxygen-18, and this disparity increases at lower temperatures. During periods of lower global temperatures, snow and rain from that evaporated water tends to be higher in oxygen-16, and
8635-430: The thermal decomposition of potassium nitrate . In Bugaj's view, the isolation of oxygen and the proper association of the substance to that part of air which is required for life, provides sufficient evidence for the discovery of oxygen by Sendivogius. This discovery of Sendivogius was however frequently denied by the generations of scientists and chemists which succeeded him. It is also commonly claimed that oxygen
8792-582: The 1-Left panel. The 1-Left panel was driven up dip from the Mains for approximately 3,100 feet (940 m). The flooded abandoned mine was located immediately up-dip of the Quecreek #1 mine permit boundary in the Upper Kittanning coal seam. At approximately 9 p.m. on Wednesday, July 24, the eighteen miners were in danger 240 feet (73 m) underground, below the fields of Dormel Farm when
8949-504: The 17th and the 18th century but none of them recognized it as a chemical element . This may have been in part due to the prevalence of the philosophy of combustion and corrosion called the phlogiston theory , which was then the favored explanation of those processes. Established in 1667 by the German alchemist J. J. Becher , and modified by the chemist Georg Ernst Stahl by 1731, phlogiston theory stated that all combustible materials were made of two parts. One part, called phlogiston,
9106-400: The 1860s onward. By the late 20th century, coal was, for the most part, replaced in domestic as well as industrial and transportation usage by oil , natural gas or electricity produced from oil, gas, nuclear power or renewable energy sources. By 2010, coal produced over a fourth of the world's energy. Coal extraction methods vary depending on whether the mine is an underground mine or
9263-476: The 25th and briefed on the rescue effort. Governor Mark Schweiker visited the site that night, said at a news briefing later that they "are in a very fragile state. We may need a little help from the Almighty." He also stated that "We are bringing every asset that is necessary to complete this rescue operation", and that anything less than the rescue of all nine of the men would be unacceptable. Many from around
9420-531: The 2s electrons, after sequential filling of the low σ and σ orbitals; σ overlap of the two atomic 2p orbitals that lie along the O–O molecular axis and π overlap of two pairs of atomic 2p orbitals perpendicular to the O–O molecular axis, and then cancellation of contributions from the remaining two 2p electrons after their partial filling of the π orbitals. This combination of cancellations and σ and π overlaps results in dioxygen's double-bond character and reactivity, and
9577-413: The 30-inch Rescue Hole No. 1 at 6:45 p.m., Thursday, July 25, to intersect 1-Left section. It was located approximately 20 feet (6.1 m) away from the 6.5-inch (170 mm) ventilation hole, and was drilled to a 105-foot (32 m) depth by 1:12 a.m., Friday, July 26, when the drill bit broke. The distance from this point to the mine was estimated at 139 feet (42 m). At 3:45 a.m.
SECTION 60
#17327979865299734-410: The 6-inch (150 mm) drill steel with a hammer, and a faint response was heard. The miners had been taking turns walking every 10 or 15 minutes 250 feet (76 m) down the passageway from their high ground location to check the area where the drilling sounds were coming from. When Hileman and Foy made the trek on Saturday at about 10:15 p.m. their cap lamps were dim, but that is when they found
9891-402: The 6-inch (150 mm) hole. At 10:53 p.m. a special pen-shaped, two-way communication device was lowered into the 6-inch air pipe, with a child's glow stick attached to it for visibility in the dark mine. Communication was established with the miners who confirmed that all nine were alive and well, except for the foreman who was experiencing chest pains. At 12:30 a.m. on July 28,
10048-414: The 8½-foot high steel mesh escape capsule, with supplies, descended into Rescue Hole No. 1, into the void where the men had languished in fear and hope for 77 hours. Due to recurring chest pains, foreman Randy Fogle was chosen to be the first rescued miner, and arrived on the surface at approximately 1:00 a.m. The removal order of the rest of the crew was based upon weight, the heaviest to lightest, as
10205-536: The American scientist Robert H. Goddard became the first person to develop a rocket engine that burned liquid fuel; the engine used gasoline for fuel and liquid oxygen as the oxidizer . Goddard successfully flew a small liquid-fueled rocket 56 m at 97 km/h on March 16, 1926, in Auburn, Massachusetts , US. In academic laboratories, oxygen can be prepared by heating together potassium chlorate mixed with
10362-484: The Philosopher's Stone drawn from the source of nature and manual experience"] (1604) described a substance contained in air, referring to it as 'cibus vitae' (food of life, ) and according to Polish historian Roman Bugaj, this substance is identical with oxygen. Sendivogius, during his experiments performed between 1598 and 1604, properly recognized that the substance is equivalent to the gaseous byproduct released by
10519-579: The Roman Empire and other early historical economies. It became important in the Industrial Revolution of the 19th and 20th centuries, when it was primarily used to power steam engines, heat buildings and generate electricity. Coal mining continues as an important economic activity today, but has begun to decline due to the strong contribution coal plays in global warming and environmental issues, which result in decreasing demand and in some geographies, peak coal . Compared to wood fuels , coal yields
10676-474: The Saxman mine was breached. A four-member team started working about 3:15 a.m. Thursday, and its drill cracked through what turned out to be 240 feet (73 m) of rock, and into the mine shaft 1 hour and 45 minutes later. On July 25, at 5:06 a.m., approximately 8 hours after the breakthrough, the 6.5-inch (170 mm) hole was drilled into the mine. The drilling rig's air compressor pushed air into
10833-438: The Sun's disk of protoplanetary material prior to the coalescence of dust grains that formed the Earth. Oxygen presents two spectrophotometric absorption bands peaking at the wavelengths 687 and 760 nm . Some remote sensing scientists have proposed using the measurement of the radiance coming from vegetation canopies in those bands to characterize plant health status from a satellite platform. This approach exploits
10990-812: The U.S., Examples include the Sago Mine disaster of 2006, and the 2007 mine accident in Utah 's Crandall Canyon Mine , where nine miners were killed and six entombed. In the decade 2005–2014, US coal mining fatalities averaged 28 per year. The most fatalities during the 2005–2014 decade were 48 in 2010, the year of the Upper Big Branch Mine disaster in West Virginia, which killed 29 miners. Chronic lung diseases, such as pneumoconiosis (black lung) were once common in miners, leading to reduced life expectancy . In some mining countries black lung
11147-624: The US Department of Labor's Mine Safety and Health Administration (MSHA) show that between 1990 and 2004, the industry cut the rate of injuries by more than half and fatalities by two-thirds. But according to the Bureau of Labor Statistics , even in 2006, mining remained the second most dangerous occupation in America, when measured by fatality rate . These numbers, however, include all mining activities, and oil and gas mining contribute to
11304-400: The Upper Kittanning coal seam. The Upper Kittanning seam locally ranges in thickness from 38 to 62 inches (970–1,570 mm) and dips 1.7 to 2.3 degrees (3 to 4 percent) to the northwest. The structural geology of the area caused the flooded mine void of the shallower Saxman Mine to be at a higher elevation than the active Quecreek Mine. The Saxman mine was located along the axis of
11461-547: The accident was the unavailability of a certified final mine map for Harrison No. 2 mine in Pennsylvania's mine map repository. Governor Mark Schweiker convened an investigation committee in the days after the rescue was completed, paying particular attention to the actions of the Black Wolf Coal Company, which had been previously cited 25 times for violations. The MSHA report concluded: "The rescue of
11618-604: The airshaft, near Entry No. 1. With water rising 70 feet (21 m) away, miner Randy Fogle estimated that they had about an hour left to live. Notes were written, prayers were said, and most of the miners roped themselves together, to die as a family. However, as dewatering continued, they noticed and confirmed the water had ceased to rise. Switching to survival mode, the drenched miners sought to conserve resources and sat back to back to fight hypothermia in their 50 °F (10 °C) environment. Crew chief Fogle in particular encouraged them, confident of rescue. Dennis Hall's lunch pail
11775-422: The anticlinal Boswell Dome and the Quecreek Mine on the western flank of the anticline . The mine was opened by Quemahoning Creek Coal Company in 1913 as Quecreek No. 2 mine. Saxman Coal and Coke Company purchased the mine in 1925 and mined it until 1963 with an idle period from 1934 through 1941. The mine had also been named Saxman, Harrison, and most recently, Harrison No. 2. The miners were working on July 24 in
11932-482: The area where the miners had taken refuge would be under water. Mine ventilation expert John Urosek, of the U.S. Mine Safety and Health Administration (MSHA), proposed creating a pressurized air pocket for the miners. Urosek's plan had never been tested in the United States, but despite some skepticism, calculations were made, and the hole was sealed around the air supply. The drill operator then used his rig's air compressor to pump and maintain 920 cubic feet per minute at
12089-493: The atmosphere. In the present equilibrium, production and consumption occur at the same rate. Free oxygen also occurs in solution in the world's water bodies. The increased solubility of O 2 at lower temperatures (see Physical properties ) has important implications for ocean life, as polar oceans support a much higher density of life due to their higher oxygen content. Water polluted with plant nutrients such as nitrates or phosphates may stimulate growth of algae by
12246-412: The bond order from three to two. Because of its unpaired electrons, triplet oxygen reacts only slowly with most organic molecules, which have paired electron spins; this prevents spontaneous combustion. In the triplet form, O 2 molecules are paramagnetic . That is, they impart magnetic character to oxygen when it is in the presence of a magnetic field, because of the spin magnetic moments of
12403-581: The coal mining jobs as part of a just transition ; however, renewable energy was not suitable in some of the geographies with high concentrations of miners, such as in China, which is far and away the leading coal-mining nation. Coal refuse (also described as coal waste, rock, slag, coal tailings, waste material, rock bank, culm, boney, or gob ) is the material left over from coal mining, usually as tailings piles or spoil tips . For every tonne of hard coal generated by mining, 400 kg (880 lb) of waste material remains, which includes some lost coal that
12560-497: The coal preparation (or wash) plant. Once this strip is empty of coal, the process is repeated with a new strip being created next to it. This method is most suitable for areas with flat terrain. Equipment to be used depends on geological conditions. For example, to remove overburden that is loose or unconsolidated, a bucket wheel excavator might be the most productive. The life of some area mines may be more than 50 years. The contour mining method consists of removing overburden from
12717-863: The coal resource may cause burial and loss of topsoil, exposes parent material, and creates large infertile wastelands. Soil disturbance and associated compaction result in conditions conducive to erosion. Soil removal from the area to be surface-mined alters or destroys many natural soil characteristics, and reduces its biodiversity and productivity for agriculture. Soil structure may be disturbed by pulverization or aggregate breakdown. Top 10 hard and brown coal producers in 2012 were (in million metric tons): China 3,621, United States 922, India 629, Australia 432, Indonesia 410, Russia 351, South Africa 261, Germany 196, Poland 144, and Kazakhstan 122. Coal has been mined in every state of Australia, but mainly in Queensland, New South Wales and Victoria. It
12874-429: The developed world. Modern coal mining in the US has an average 23 deaths per year due to mine accidents (2001–2020). However, in lesser developed countries and some developing countries, many miners continue to die annually, either through direct accidents in coal mines or through adverse health consequences from working under poor conditions. China , in particular, has the highest number of coal mining related deaths in
13031-444: The diatomic elemental molecules in those gases. The first commercial method of producing oxygen was chemical, the so-called Brin process involving a reversible reaction of barium oxide . It was invented in 1852 and commercialized in 1884, but was displaced by newer methods in early 20th century. By the late 19th century scientists realized that air could be liquefied and its components isolated by compressing and cooling it. Using
13188-455: The disruptive activities of blasting, ripping, and excavating coal. Stripping of overburden eliminates and destroys archeological and historic features, unless they are removed beforehand. The removal of vegetative cover and activities associated with the construction of haul roads, stockpiling of topsoil, displacement of overburden and hauling of soil and coal increase the quantity of dust around mining operations. Dust degrades air quality in
13345-535: The documentary, Get Out Alive on the Discovery Channel Dennis Hall died on May 13, 2022. The Dropkick Murphys song "Buried Alive" on their 2003 album Blackout is a tribute to the Quecreek Mine rescue. Singer–songwriter Anaïs Mitchell recorded a song entitled "Quecreek Flood" on her 2004 album Hymns for the Exiled . The song explores the political and personal implications of
13502-421: The drill opening and Hileman alerted the others. Immediately after the rescue hole penetrated the mine, all equipment was shut down in order to take an accurate relative air pressure reading between the mine and surface atmospheres. The pressure reading was zero, indicating that the pressures were equal and that the airlock would not be required. The compressor was turned off and the drill steels were removed from
13659-431: The drilling site. Drilling continued until 1:38 p.m. on July 27, when it was stopped to install the air lock and wait for the water to be pumped down to an elevation of 1,829 feet (557 m) mean sea level (MSL), approximately 10 feet (3.0 m) below the portal elevation. Drilling started again at 4:45 p.m., but at 8:11 p.m. the rings in the airlock failed and had to be repaired. At 8:58 p.m.
13816-466: The electron spins are paired. It is much more reactive with common organic molecules than is normal (triplet) molecular oxygen. In nature, singlet oxygen is commonly formed from water during photosynthesis, using the energy of sunlight. It is also produced in the troposphere by the photolysis of ozone by light of short wavelength and by the immune system as a source of active oxygen. Carotenoids in photosynthetic organisms (and possibly animals) play
13973-572: The fact that the Englishman Priestley had first isolated the gas and written about it. This is partly due to a poem praising the gas titled "Oxygen" in the popular book The Botanic Garden (1791) by Erasmus Darwin , grandfather of Charles Darwin . John Dalton 's original atomic hypothesis presumed that all elements were monatomic and that the atoms in compounds would normally have the simplest atomic ratios with respect to one another. For example, Dalton assumed that water's formula
14130-571: The fatalities occurring in the first half of the 20th century. 3,242 died in 1907, the worst year ever; in 2020 there were five. Open cut hazards are principally mine wall failures and vehicle collisions; underground mining hazards include suffocation, gas poisoning, roof collapse, rock burst , outbursts , and gas explosions. Firedamp explosions can trigger the far more dangerous coal dust explosions, which can engulf an entire mine. Most of these risks are greatly reduced in modern mines, and multiple fatality incidents are now rare in most parts of
14287-399: The first known experiments on the relationship between combustion and air was conducted by the 2nd century BCE Greek writer on mechanics, Philo of Byzantium . In his work Pneumatica , Philo observed that inverting a vessel over a burning candle and surrounding the vessel's neck with water resulted in some water rising into the neck. Philo incorrectly surmised that parts of the air in
14444-428: The flooded Saxman mine was breached as the mining progressed eastward. Water had broken through the face and was inundating the entry, and the nine miners in the 1-Left panel area used the mine's phone system to notify the other group of nine miners in the 2-Left panel to evacuate immediately. These miners were able to escape at around 9:45 p.m. and alert others, and a 911 call was made at 9:53 p.m. However,
14601-457: The genetic soil profile, displaces or destroys wildlife and habitat, alters current land uses, and to some extent permanently changes the general topography of the area mined. Adverse impacts on geological features of human interest may occur in a coal strip mine. Geomorphic and geophysical features and outstanding scenic resources may be sacrificed by indiscriminate mining. Paleontological, cultural, and other historic values may be endangered due to
14758-414: The hole had to be enlarged from the surface. This operation started at approximately 8:40 p.m. on Friday. Enlarging the first rescue hole with the new 30-inch (760 mm) bit began at 1 a.m. on July 27, but later stopped to replace the sleeve . At 2:30 p.m. drilling was stopped again as the operation damaged the outer cutting bits and a new bit assembly was needed. At 3:30 a.m.
14915-399: The idea; instead, it was based on observations of what happens when something burns, that most common objects appear to become lighter and seem to lose something in the process. Polish alchemist , philosopher , and physician Michael Sendivogius (Michał Sędziwój) in his work De Lapide Philosophorum Tractatus duodecim e naturae fonte et manuali experientia depromti ["Twelve Treatises on
15072-450: The immediate area, has an adverse impact on vegetative life, and constitutes health and safety hazards for mine workers and nearby residents. Surface mining disrupts virtually all aesthetic elements of the landscape. Alteration of land forms often imposes unfamiliar and discontinuous configurations. New linear patterns appear as material is extracted and waste piles are developed. Different colors and textures are exposed as vegetative cover
15229-457: The inrush of water made similarly good decisions. Their knowledge of escape ways and escape procedures aided their escape. The fast actions of company officials in calling for assistance of expert personnel and appropriate equipment, and the rapid response of those contacted played a major role in the success of this rescue." A memorial park was created at the farm field where the drilling rescue operations occurred. The park at Dormel Farms lies to
15386-416: The last would have no assistance getting into the capsule. The miners were brought up in 15-minute intervals, and all nine miners were on the surface by 2:45 a.m. None of the miners suffered from decompression sickness, and they were transferred either by helicopter (flying at low altitudes) or by ambulance to hospitals. However, because the drill shaft had gone through an aquifer, in their final exits
15543-504: The letter was found in Scheele's belongings after his death). Lavoisier conducted the first adequate quantitative experiments on oxidation and gave the first correct explanation of how combustion works. He used these and similar experiments, all started in 1774, to discredit the phlogiston theory and to prove that the substance discovered by Priestley and Scheele was a chemical element . In one experiment, Lavoisier observed that there
15700-443: The lowest area in the mine. Additional dewater holes were drilled to accelerate dewatering. Back underground, rising water covered the air shaft, preventing the miners from tapping on the pipe, though for a time they used a hammer to bang on the rock ceiling, detectable by seismic equipment which was brought in by Federal mining officials. By noon Thursday, the miners had to retreat to the highest ground, about 300 feet (91 m) from
15857-552: The main source of primary energy for industry and transportation in industrial areas from the 18th century to the 1950s. Coal remains an important energy source. Coal is also mined today on a large scale by open pit methods wherever the coal strata strike the surface or are relatively shallow. Britain developed the main techniques of underground coal mining from the late 18th century onward, with further progress being driven by 19th-century and early 20th-century progress. However, oil and gas were increasingly used as alternatives from
16014-404: The majority of fatalities. Coal mining resulted in 47 fatalities that year. One study, though, has suggested that hazards of modern mining are now more accretive with workers facing long-term health impacts, such as sleep deprivation, that build up over time. Strip mining severely alters the landscape, which reduces the value of the natural environment in the surrounding land. The land surface
16171-428: The majority of these have half-lives that are less than 83 milliseconds. The most common decay mode of the isotopes lighter than O is β decay to yield nitrogen, and the most common mode for the isotopes heavier than O is beta decay to yield fluorine . Oxygen is the most abundant chemical element by mass in the Earth's biosphere , air, sea and land. Oxygen is the third most abundant chemical element in
16328-461: The method of extraction. For example, a study has found that among surface coal mine operations, dragline equipment produced the loudest sound at a range of 88–112 dBA. Within longwall sections, stageloaders used to transport coal from the mining face and shearers used for extraction represent some of the highest noise exposures. Auxiliary fans (up to 120 dBA), continuous mining machines (up to 109 dBA), and roof bolters (up to 103 dBA) represent some of
16485-415: The mine rescue first focused on getting air to the trapped miners. With the help of Bob Long, an engineer technician for Civil Mining Environmental Engineering, GPS measurements were made and a 6.5-inch-diameter (170 mm) borehole was begun at 2:05 a.m. The borehole was drilled to allow air to be pumped into the mineshaft where the miners were presumed to be, at the most up dip location near where
16642-458: The mine rushing upward and drowning the miners. An additional and possibly fatal danger was that of the miners being afflicted with decompression sickness , due to their breathing air which was at a higher pressure than the surface pressure, due to the pressure of the surrounding water. In preparation for these possibilities, an airlock was fashioned to go on top of the escape shaft, and on Thursday evening, 10 portable hyperbaric chambers arrived at
16799-412: The mine was flooding too rapidly for the miners in the 1-Left panel area to evacuate. Twice they tried to travel in the four-foot-high tunnels over 3,000 feet (910 m) to a shaft that would lead them to the surface, but these were also flooded. Back on the surface, Pennsylvania State Police were guarding the Quecreek mine site by 10:30 p.m., and instructed reporters to go to the local church for
16956-507: The mine, and the air returns from the borehole showed a marginal air quality of 19.3 percent oxygen. Rescue workers tapped on the inserted air pipe, and at 5:12 a.m. received three strong bangs in response, followed by nine taps at 11:40 a.m. However, while the drilling rig's compressed air rapidly increased the oxygen content of the mine air, monitors showed the rising water was approaching 1,825 feet (556 m) above sea level, and rescuers feared they had perhaps an hour before
17113-529: The miners had been drenched in yet another torrent of cold water. Extremities were purple and mottled from immersion, and trauma surgeon Dr. Russell Dumire stated that "They were freezing cold... It looked like if you rubbed real hard against their feet, you could rub the skin right off." The lowest body temperature among the miners was about 92.5 °F (33.6 °C) degrees, the warmest at 96.8 °F (36.0 °C), versus normal body temperature of 98.6 °F (37.0 °C). In order of rescue: Randall Fogle
17270-469: The mining disaster. Books Coal mine Coal mining is the process of extracting coal from the ground or from a mine. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production. In the United Kingdom and South Africa ,
17427-465: The mining workforce. in 2015 US coal mines had 65,971 employees, the lowest figure since EIA began collecting data in 1978. However, a 2016 study reported that a relatively minor investment would allow most coal workers to retrain for the solar energy industry. Coal mining has been a very dangerous activity and the list of historical coal mining disasters is long. In the U.S., 104,895 coal miners were killed in mine accidents since 1900, 90 percent of
17584-418: The most successful and biodiverse terrestrial clade , oxygen is directly conducted to the internal tissues via a deep network of airways . Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins , nucleic acids , carbohydrates and fats , as do the major constituent inorganic compounds of animal shells, teeth, and bone. Most of the mass of living organisms
17741-494: The nitroaereus must have combined with it. He also thought that the lungs separate nitroaereus from air and pass it into the blood and that animal heat and muscle movement result from the reaction of nitroaereus with certain substances in the body. Accounts of these and other experiments and ideas were published in 1668 in his work Tractatus duo in the tract "De respiratione". Robert Hooke , Ole Borch , Mikhail Lomonosov , and Pierre Bayen all produced oxygen in experiments in
17898-469: The noisiest equipment within continuous mining sections. Exposures to noise exceeding 90 dBA can lead to adverse effects on workers' hearing. The use of administrative controls and engineering controls can be used to reduce noise exposures. Improvements in mining methods (e.g. longwall mining), hazardous gas monitoring (such as safety-lamps or more modern electronic gas monitors), gas drainage, electrical equipment , and ventilation have reduced many of
18055-555: The north of the Somerset County Historical Society on Pennsylvania Route 985 . A few books were written about the account. The miners themselves wrote a book about their ordeal. In 2002, the story was dramatized by ABC in a television movie , The Pennsylvania Miners' Story . In 2003, rescuer Bob Long died from suicide, a reminder that depression often follows the event among those involved in high-profile rescues. In 2004, Bill and Lori Arnold,
18212-590: The open pit methods, due to thickness of the seam 20–25 metres (60–90 feet). Coals occurring below 90 m (300 ft) are usually deep mined. However, there are open pit mining operations working on coal seams up to 300–460 metres (1,000–1,500 feet) below ground level, for instance Tagebau Hambach in Germany. When coal seams are near the surface, it may be economical to extract the coal using open-cut , also referred to as open-cast, open-pit, mountaintop removal or strip, mining methods. Opencast coal mining recovers
18369-421: The operation reaches a predetermined stripping ratio (tons of overburden/tons of coal), it is not profitable to continue. Depending on the equipment available, it may not be technically feasible to exceed a certain height of highwall. At this point, it is possible to produce more coal with the augering method in which spiral drills bore tunnels into a highwall laterally from the bench to extract coal without removing
18526-408: The overburden. Mountaintop coal mining is a surface mining practice involving removal of mountaintops to expose coal seams, and disposing of associated mining overburden in adjacent "valley fills." Valley fills occur in steep terrain where there are limited disposal alternatives. Mountaintop removal mining combines area and contour strip mining methods. In areas with rolling or steep terrain with
18683-476: The owners of Dormel Farms where the rescue took place, wrote their memories of the rescue in a book coauthored by Joyann Dwire entitled Miracle at Dormel Farms . It purports to describe a "series of smaller miracles which culminated in the Miracle Of Quecreek—the rescue of nine miners". In 2010, the rescue was featured on the documentary, I Survived... on Bio . In 2010, the rescue was featured on
18840-454: The photosynthetic activities of autotrophs such as cyanobacteria , chloroplast -bearing algae and plants. A much rarer triatomic allotrope of oxygen , ozone ( O 3 ), strongly absorbs the UVB and UVC wavelengths and forms a protective ozone layer at the lower stratosphere , which shields the biosphere from ionizing ultraviolet radiation . However, ozone present at the surface
18997-405: The pit and put into operation in the afternoon. A 6-inch (150 mm) drop in the water level was reported between 4:00 and 6:00 p.m. The pumping discharge rate fluctuated constantly as new pumps arrived and changes were made. The maximum pumping rate achieved was approximately 27,000 gpm at the mine pit. Additional borehole locations were surveyed on the surface for holes to be drilled into
19154-473: The pit as they arrived. At 8:33 a.m. Thursday, the first of several diesel pumps arrived at the mine site. Before this pump arrived, only two submersible pumps were operating in the sump area of the pit. At 11:05 a.m., water was four to five feet deep in the mine pit entrance. Water in the pit reached a maximum elevation of 1,856.8 feet (566.0 m) at approximately 4:00 p.m., Thursday, July 25. High-capacity diesel pumps were installed in
19311-425: The potential to spontaneously ignite. Because most coal refuse harbors toxic components, it is not easily reclaimed by replanting with plants like beach grasses. The use of sophisticated sensing equipment to monitor air quality is common and has replaced the use of small animals such as canaries, often referred to as " miner's canaries ". In the United States, the increase in technology has significantly decreased
19468-458: The remainder of this article. Trioxygen ( O 3 ) is usually known as ozone and is a very reactive allotrope of oxygen that is damaging to lung tissue. Ozone is produced in the upper atmosphere when O 2 combines with atomic oxygen made by the splitting of O 2 by ultraviolet (UV) radiation. Since ozone absorbs strongly in the UV region of the spectrum , the ozone layer of
19625-472: The repairs were completed on the No. 1 drill air lock and drilling resumed. At 10 p.m. the water elevation was 1827.92 MSL. The No. 1 drill cut through into the mine at 10:16 p.m. at a depth of 239.6 feet (73.0 m), which was then lower than the elevation of the mine’s portal. Drilling of a second escape hole had also been underway, in case it would be needed. At 7 a.m. on July 27, this hole
19782-399: The risks of rock falls, explosions, and unhealthy air quality. Gases released during the mining process can be recovered to generate electricity and improve worker safety with gas engines . Another innovation in recent years is the use of closed circuit escape respirators , respirators that contain oxygen for situations where mine ventilation is compromised. Statistical analyses performed by
19939-565: The seam in a pattern following the contours along a ridge or around the hillside. This method is most commonly used in areas with rolling to steep terrain. It was once common to deposit the spoil on the downslope side of the bench thus created, but this method of spoil disposal consumed much additional land and created severe landslide and erosion problems. To alleviate these problems, a variety of methods were devised to use freshly cut overburden to refill mined-out areas. These haul-back or lateral movement methods generally consist of an initial cut with
20096-414: The seawater left behind tends to be higher in oxygen-18. Marine organisms then incorporate more oxygen-18 into their skeletons and shells than they would in a warmer climate. Paleoclimatologists also directly measure this ratio in the water molecules of ice core samples as old as hundreds of thousands of years. Planetary geologists have measured the relative quantities of oxygen isotopes in samples from
20253-432: The spoil deposited downslope or at some other site and spoil from the second cut refilling the first. A ridge of undisturbed natural material 15 to 20 ft (5 to 6 m) wide is often intentionally left at the outer edge of the mined area. This barrier adds stability to the reclaimed slope by preventing spoil from slumping or sliding downhill. The limitations of contour strip mining are both economic and technical. When
20410-476: The surface or overburden, of the mining area. The overburden is then removed by draglines or by shovel and truck. Once the coal seam is exposed, it is drilled, fractured and thoroughly mined in strips. The coal is then loaded onto large trucks or conveyors for transport to either the coal preparation plant or directly to where it will be used. Most open cast mines in the United States extract bituminous coal . In Canada, Australia, and South Africa, open cast mining
20567-414: The tool in, and the bit was retrieved from Rescue Hole No. 1 at 4:09 p.m. on July 26. The failure of drilling equipment stopped progress at this borehole for about 18 hours. The miners were concerned. Foley opined that they might have plugged up or might have broken a bit, and reassured the others that drilling would surely begin again. The miners' relatives were taken to the mine on the afternoon of
20724-422: The trapped miners was a major success. Fogle’s decision and Hall’s persistence to immediately notify the miners in 2-Left section was life saving because of the rapid inflow of water. Without that timely warning they would not have been able to escape. Additionally, the 1-Left section crew’s decisions to stay together, work as a team, and go to the highest ground were crucial for their survival. The miners who escaped
20881-524: The two basic methods of mining. The choice of mining method depends primarily on depth, density, overburden, and thickness of the coal seam; seams relatively close to the surface, at depths less than approximately 55 m (180 ft), are usually surface mined. Coal that occurs at depths of 55 to 90 m (180 to 300 ft) are usually deep mined, but in some cases surface mining techniques can be used. For example, some western U.S. coal that occur at depths in excess of 60 m (200 ft) are mined by
21038-440: The universe after hydrogen and helium . At standard temperature and pressure , two oxygen atoms will bind covalently to form dioxygen , a colorless and odorless diatomic gas with the chemical formula O 2 . Dioxygen gas currently constitutes 20.95% molar fraction of the Earth's atmosphere , though this has changed considerably over long periods of time in Earth's history . Oxygen makes up almost half of
21195-486: The universe, after hydrogen and helium. About 0.9% of the Sun 's mass is oxygen. Oxygen constitutes 49.2% of the Earth's crust by mass as part of oxide compounds such as silicon dioxide and is the most abundant element by mass in the Earth's crust . It is also the major component of the world's oceans (88.8% by mass). Oxygen gas is the second most common component of the Earth's atmosphere , taking up 20.8% of its volume and 23.1% of its mass (some 10 tonnes). Earth
21352-401: The unpaired electrons in the molecule, and the negative exchange energy between neighboring O 2 molecules. Liquid oxygen is so magnetic that, in laboratory demonstrations, a bridge of liquid oxygen may be supported against its own weight between the poles of a powerful magnet. Singlet oxygen is a name given to several higher-energy species of molecular O 2 in which all
21509-435: The upper atmosphere functions as a protective radiation shield for the planet. Near the Earth's surface, it is a pollutant formed as a by-product of automobile exhaust . At low earth orbit altitudes, sufficient atomic oxygen is present to cause corrosion of spacecraft . The metastable molecule tetraoxygen ( O 4 ) was discovered in 2001, and was assumed to exist in one of the six phases of solid oxygen . It
21666-452: The use of draglines , trucks, conveyors , hydraulic jacks , and shearers. The coal mining industry has a long history of significant negative environmental impacts on local ecosystems, health impacts on local communities and workers, and contributes heavily to the global environmental crises, such as poor air quality and climate change . For these reasons, coal has been one of the first fossil fuels to be phased out of various parts of
21823-451: The vessel were converted into the classical element fire and thus were able to escape through pores in the glass. Many centuries later Leonardo da Vinci built on Philo's work by observing that a portion of air is consumed during combustion and respiration . In the late 17th century, Robert Boyle proved that air is necessary for combustion. English chemist John Mayow (1641–1679) refined this work by showing that fire requires only
21980-528: The water inundation was the use of an undated and uncertified mine map of the Harrison No. 2 mine that did not show the complete and final mine workings. Using this map led to an inaccurate depiction of the Harrison No. 2 mine workings on the Quecreek #1 mine map required by MSHA and on the certified mine map submitted to the Commonwealth of Pennsylvania during the permitting process. The root cause of
22137-434: The water level needed to be lowered to prevent the loss of the air pocket in the mine area where the nine miners would congregate. Should a rescue hole penetrate the mine, the air pocket could escape and the air filled void area become flooded, and the miners would drown. The second grave concern was the quality of the air in the mine. Pumps were set up as they became available. Work proceeded immediately to install pumps in
22294-531: The world called, emailed, and prayed in support of the rescue. The news media covered the story with optimistic reporting. Many were returning to stay at the same Somerset hotels they had previously occupied while covering the United Airlines Flight 93 crash site, located ten miles (16 km) away, less than a year earlier. A new 30-inch (760 mm) bit arrived from West Virginia at 7:00 p.m. Friday, but due to its nominally larger size,
22451-441: The world, with official statistics claiming that 6,027 deaths occurred in 2004. To compare, 28 deaths were reported in the U.S. in the same year. Coal production in China is twice that in the US, while the number of coal miners is around 50 times that of the US, making deaths in coal mines in China 4 times as common per worker (108 times as common per unit output) as in the US. Mine disasters have still occurred in recent years in
22608-428: Was HO, leading to the conclusion that the atomic mass of oxygen was 8 times that of hydrogen, instead of the modern value of about 16. In 1805, Joseph Louis Gay-Lussac and Alexander von Humboldt showed that water is formed of two volumes of hydrogen and one volume of oxygen; and by 1811 Amedeo Avogadro had arrived at the correct interpretation of water's composition, based on what is now called Avogadro's law and
22765-406: Was at a depth of 160 feet (49 m) when drilling became very hard, and at 1:31 p.m. the No. 2 drill lost its bit, hammer, and reamer in the borehole at approximately 204 feet (62 m). Repairs were being made when Rescue Hole No. 1 broke through into the mine, and drilling then ceased. After Rescue Hole No. 1 broke through into the mine, rescuers signaled the trapped miners by tapping on
22922-530: Was discovered floating and was retrieved, with the still dry corned beef sandwich his wife had made him, and a bottle of Pepsi , while Thomas Foy found two Mountain Dews on one of their machines. The miners at this point could hear the drilling getting nearer, but at 1:50 a.m. Friday it stopped. A "super drill", capable of drilling a 30-inch (760 mm) hole, had been sent with police escort up from West Virginia. Once oxygen purging began, drillers had begun
23079-408: Was first discovered by Swedish pharmacist Carl Wilhelm Scheele . He had produced oxygen gas by heating mercuric oxide (HgO) and various nitrates in 1771–72. Scheele called the gas "fire air" because it was then the only known agent to support combustion. He wrote an account of this discovery in a manuscript titled Treatise on Air and Fire , which he sent to his publisher in 1775. That document
23236-451: Was given off when the substance containing it was burned, while the dephlogisticated part was thought to be its true form, or calx . Highly combustible materials that leave little residue , such as wood or coal, were thought to be made mostly of phlogiston; non-combustible substances that corrode, such as iron, contained very little. Air did not play a role in phlogiston theory, nor were any initial quantitative experiments conducted to test
23393-491: Was independently developed in 1895 by German engineer Carl von Linde and British engineer William Hampson . Both men lowered the temperature of air until it liquefied and then distilled the component gases by boiling them off one at a time and capturing them separately. Later, in 1901, oxyacetylene welding was demonstrated for the first time by burning a mixture of acetylene and compressed O 2 . This method of welding and cutting metal later became common. In 1923,
23550-531: Was mined, and 375.1 million tonnes was exported. In 2013/14, coal provided about 69% of Australia's electricity production. In 2013, Australia was the world's fifth-largest coal producer, after China, the United States, India, and Indonesia. However, in terms of proportion of production exported, Australia is the world's second largest coal exporter, as it exports roughly 73% of its coal production. Indonesia exports about 87% of its coal production. A court in Australia has cited climate change in ruling against
23707-445: Was no overall increase in weight when tin and air were heated in a closed container. He noted that air rushed in when he opened the container, which indicated that part of the trapped air had been consumed. He also noted that the tin had increased in weight and that increase was the same as the weight of the air that rushed back in. This and other experiments on combustion were documented in his book Sur la combustion en général , which
23864-465: Was not sensibly different from that of common air , but I fancied that my breast felt peculiarly light and easy for some time afterwards." Priestley published his findings in 1775 in a paper titled "An Account of Further Discoveries in Air", which was included in the second volume of his book titled Experiments and Observations on Different Kinds of Air . Because he published his findings first, Priestley
24021-408: Was proven in 2006 that this phase, created by pressurizing O 2 to 20 GPa , is in fact a rhombohedral O 8 cluster . This cluster has the potential to be a much more powerful oxidizer than either O 2 or O 3 and may therefore be used in rocket fuel . A metallic phase was discovered in 1990 when solid oxygen is subjected to a pressure of above 96 GPa and it
24178-504: Was published in 1777. In the meantime, on August 1, 1774, an experiment conducted by the British clergyman Joseph Priestley focused sunlight on mercuric oxide contained in a glass tube, which liberated a gas he named "dephlogisticated air". He noted that candles burned brighter in the gas and that a mouse was more active and lived longer while breathing it. After breathing the gas himself, Priestley wrote: "The feeling of it to my lungs
24335-462: Was published in 1777. In that work, he proved that air is a mixture of two gases; 'vital air', which is essential to combustion and respiration, and azote (Gk. ἄζωτον "lifeless"), which did not support either. Azote later became nitrogen in English, although it has kept the earlier name in French and several other European languages. Lavoisier renamed 'vital air' to oxygène in 1777 from
24492-420: Was shown in 1998 that at very low temperatures, this phase becomes superconducting . Oxygen dissolves more readily in water than nitrogen, and in freshwater more readily than in seawater. Water in equilibrium with air contains approximately 1 molecule of dissolved O 2 for every 2 molecules of N 2 (1:2), compared with an atmospheric ratio of approximately 1:4. The solubility of oxygen in water
24649-461: Was the most seriously affected of the nine miners and complained of chest pains upon his rescue; he was also suffering through the rescue. All have since made full recoveries. While some are still in the industry, Fogle is the only member of the group who still works underground. Dennis Hall retired from the industry and vowed never to mine again. An investigation was completed by the U.S. Mine Safety and Health Administration . The primary cause of
#528471