title: Shawnee

text: Some Shawnee occupied areas in central Pennsylvania. Long without a chief, in 1714 they asked Carondawana, an Oneida war chief, to represent them to the Pennsylvania provincial council. About 1727 Carondawana and his wife, a prominent interpreter known as Madame Montour, settled at Otstonwakin, on the west bank at the confluence of Loyalsock Creek and the West Branch Susquehanna River.


title: Shawnee

text: By 1730, European-American settlers began to arrive in the Shenandoah Valley of Virginia, where the Shawnee predominated in the northern part of the valley. They were claimed as tributaries by the "Haudenosaunee" or Six Nations of the Iroquois to the north. The Iroquois had helped some of the Tuscarora people from North Carolina, who were also Iroquoian speaking and distant relations, to resettle in the vicinity of what is now Martinsburg, West Virginia. Most of the Tuscarora migrated to New York and settled near the Oneida people, becoming the sixth nation of the Iroquois Confederacy; they declared their migration finished in 1722. Also at this time, Seneca (an Iroquois nation) and Lenape war parties from the north often fought pitched battles with pursuing bands of Catawba from Virginia, who would overtake them in the Shawnee-inhabited regions of the Valley.


title: Shawnee

text: By the late 1730s pressure from colonial expansion produced repeated conflicts. Shawnee communities were also impacted by the fur trade. While they gained arms and European goods, they also traded for rum or brandy, leading to serious social problems related to alcohol abuse by their members. Several Shawnee communities in the Province of Pennsylvania, led by Peter Chartier, a métis trader, opposed the sale of alcohol in their communities. This resulted in a conflict with colonial Governor Patrick Gordon, who was under pressure from traders to allow rum and brandy in trade. Unable to protect themselves, in 1745 some 400 Shawnee migrated from Pennsylvania to Ohio, Kentucky, Alabama and Illinois, hoping to escape the traders' influence.


title: Shawnee

text: Prior to 1754, the Shawnee had a headquarters at Shawnee Springs at modern-day Cross Junction, Virginia. The father of the later chief Cornstalk held his council there. Several other Shawnee villages were located in the northern Shenandoah Valley: at Moorefield, West Virginia, on the North River; and on the Potomac at Cumberland, Maryland. In 1753, the Shawnee on the Scioto River in the Ohio Country sent messengers to those still in the Shenandoah Valley, suggesting that they cross the Alleghenies to join the people further west, which they did the following year. The community known as "Shannoah" (Lower Shawneetown) on the Ohio River increased to around 1,200 people by 1750.


title: Shawnee

text: Ever since the Beaver Wars, the Haudenosaunee Confederacy had claimed the Ohio Country as their hunting ground by right of conquest, and treated the Shawnee and Lenape who resettled there as dependent tribes. Some independent Iroquois bands from various tribes also migrated westward, where they became known in Ohio as the Mingo. These three tribes—the Shawnee, the Delaware (Lenape), and the Mingo—became closely associated with one another, despite the differences in their languages. The first two spoke Algonquian languages and the third an Iroquoian language.


title: Shawnee

text: After taking part in the first phase of the French and Indian War (also known as "Braddock's War") as allies of the French, the Shawnee switched sides in 1758. They made formal peace with the British colonies at the Treaty of Easton, which recognized the Allegheny Ridge (the Eastern Divide) as their mutual border. This peace lasted only until Pontiac's War erupted in 1763, following Britain's defeat of France and takeover of its territory east of the Mississippi River in North America. Later that year, the Crown issued the Proclamation of 1763, legally confirming the 1758 border as the limits of British colonization. They reserved the land beyond for Native Americans. But the Crown had difficulty enforcing the boundary, as Anglo-European colonists continued to move westward.


title: Shawnee

text: The Treaty of Fort Stanwix in 1768 extended the colonial boundary to the west, giving British colonists a claim to lands in what are now the states of West Virginia and Kentucky. The Shawnee did not agree to this treaty: it was negotiated between British officials and the Haudenosaunee Confederacy, who claimed sovereignty over the land. While they predominated, the Shawnee and other Native American tribes also hunted there. After the Stanwix treaty, Anglo-Americans began pouring into the Ohio River Valley for settlement, frequently traveling by boats and barges along the Ohio River. Violent incidents between settlers and Indians escalated into Lord Dunmore's War in 1774. British diplomats managed to isolate the Shawnee during the conflict: the Iroquois and the Lenape stayed neutral. The Shawnee faced the British colony of Virginia with only a few Mingo allies. Lord Dunmore, royal governor of Virginia, launched a two-pronged invasion into the Ohio Country. The Shawnee chief Cornstalk attacked one wing but fought to a draw in the only major battle of the war, the Battle of Point Pleasant. In the Treaty of Camp Charlotte ending the war (1774), Cornstalk and the Shawnee were compelled by the British to recognize the Ohio River as their southern border, which had been established by the Fort Stanwix treaty. By this treaty, the Shawnee ceded all claims to the "hunting grounds" of West Virginia and Kentucky south of the Ohio River. But many other Shawnee leaders refused to recognize this boundary. The Shawnee and most other tribes were highly decentralized, and bands and towns typically made their own decisions about alliances.


title: Shawnee

text: When the United States declared independence from the British crown in 1776, the Shawnee were divided. They did not support the American rebel cause. Cornstalk led the minority who wished to remain neutral. The Shawnee north of the Ohio River were unhappy about the American settlement of Kentucky. Colin Calloway reports that most Shawnees allied with the British against the Americans, hoping to be able to expel the settlers from west of the mountains.


title: Shawnee

text: War leaders such as Blackfish and Blue Jacket joined Dragging Canoe and a band of Cherokee along the lower Tennessee River and Chickamauga Creek against the colonists in that area. Some colonists called this group of Cherokee the Chickamauga, because they lived along that river at the time of what became known as the Cherokee–American wars, during and after the American Revolution. But they were never a separate tribe, as some accounts suggested.


title: Shawnee

text: After the Revolution and during the Northwest Indian War, the Shawnee collaborated with the Miami to form a great fighting force in the Ohio Valley. They led a confederation of warriors of Native American tribes in an effort to expel U.S. settlers from that territory. After being defeated by U.S. forces at the Battle of Fallen Timbers in 1794, most of the Shawnee bands signed the Treaty of Greenville the next year. They were forced to cede large parts of their homeland to the new United States. Other Shawnee groups rejected this treaty, migrating independently to Missouri west of the Mississippi River, where they settled along Apple Creek. The French called their settlement "Le Grand Village Sauvage."


title: Shawnee

text: In the early 19th century, the Shawnee leader Tecumseh gained renown for organizing his namesake confederacy to oppose American expansion in Native American lands. The resulting conflict came to be known as Tecumseh's War. The two principal adversaries in the conflict, chief Tecumseh and General William Henry Harrison, had both been junior participants in the Battle of Fallen Timbers in 1794. Tecumseh was not among the Native American signers of the Treaty of Greenville. However, many Indian leaders in the region accepted the Greenville terms, and for the next ten years pan-tribal resistance to American hegemony faded.


title: Shawnee

text: In September 1809 Harrison, as governor of the Indiana Territory, invited the Potawatomi, Lenape, Eel River people, and the Miami to a meeting at Fort Wayne. In the negotiations, Harrison promised large subsidies to the tribes if they would cede the lands he was asking for. After two weeks of negotiating, the Potawatomi leaders convinced the Miami to accept the treaty as reciprocity, because the Potawatomi had earlier accepted treaties less advantageous to them at the request of the Miami. Finally the tribes signed the Treaty of Fort Wayne on September 30, 1809, thereby selling the United States over 3,000,000 acres (approximately 12,000 km), chiefly along the Wabash River north of Vincennes, Indiana.


title: Shawnee

text: Tecumseh was outraged by the Treaty of Fort Wayne, believing that American Indian land was owned in common by all tribes, an idea advocated in previous years by the Shawnee leader Blue Jacket and the Mohawk leader Joseph Brant. In response, Tecumseh began to expand on the teachings of his brother Tenskwatawa, a spiritual leader known as The Prophet who called for the tribes to return to their ancestral ways. He began to associate these teachings with the idea of a pan-tribal alliance. Tecumseh traveled widely, urging warriors to abandon accommodationist chiefs and to join the resistance at Prophetstown. In August 1810, Tecumseh led 400 armed warriors to confront Governor Harrison in Vincennes. Tecumseh demanded that Harrison nullify the Fort Wayne treaty, threatening to kill the chiefs who had signed it. Harrison refused, saying that the Miami were the owners of the land and could sell it if they so chose. Tecumseh left peacefully but warned Harrison that he would seek an alliance with the British unless the treaty was nullified.


title: Shawnee

text: In March the Great Comet of 1811 appeared. During the next year, tensions between American colonists and Native Americans rose quickly. Four settlers were murdered along the Missouri River and, in another incident, natives seized a boatload of supplies from a group of traders. Harrison summoned Tecumseh to Vincennes to explain the actions of his allies. In August 1811, the two leaders met, with Tecumseh assuring Harrison that the Shawnee intended to remain at peace with the United States.


title: Shawnee

text: Afterward Tecumseh traveled to the Southeast on a mission to recruit allies against the United States from among the "Five Civilized Tribes." His name "Tekoomsē" meant "Shooting Star" or "Panther Across The Sky."


title: Shawnee

text: Tecumseh told the Choctaw, Chickasaw, Muscogee, and many others that the comet of March 1811 had signaled his coming. He also said that the people would see a sign proving that the Great Spirit had sent him.


title: Shawnee

text: While Tecumseh was traveling, both sides readied for the Battle of Tippecanoe. Harrison assembled a small force of army regulars and militia to combat the Native forces. On November 6, 1811, Harrison led this army of about 1,000 men to Prophetstown, Indiana, hoping to disperse Tecumseh's confederacy. Early next morning, forces under The Prophet prematurely attacked Harrison's army at the Tippecanoe River near the Wabash. Though outnumbered, Harrison repulsed the attack, forcing the Natives to retreat and abandon Prophetstown. Harrison's men burned the village and returned home.


title: Shawnee

text: On December 11, 1811, the New Madrid earthquake shook the Muscogee lands and the Midwest. While the interpretation of this event varied from tribe to tribe, they agreed that the powerful earthquake had to have spiritual significance. The earthquake and its aftershocks helped the Tecumseh resistance movement as the Muscogee and other Native American tribes believed it was a sign that the Shawnee must be supported and that Tecumseh had prophesied such an event and sign.


title: Shawnee

text: The Muscogee (Creek) who joined Tecumseh's confederation were known as the Red Sticks. They were the more conservative and traditional part of the people, as their communities in the Upper Towns were more isolated from European-American settlements. They did not want to assimilate. The Red Sticks rose in resisting the Lower Creek, and the bands became involved in civil war, known as the Creek War. This became part of the War of 1812 when open conflict broke out between American soldiers and the Red Sticks of the Creek.


title: Shawnee

text: After William Hull's surrender of Detroit to the British during the War of 1812, General William Henry Harrison was given command of the U.S. Army of the Northwest. He set out to retake the city, which was defended by British Colonel Henry Procter, together with Tecumseh and his forces. A detachment of Harrison's army was defeated at Frenchtown along the River Raisin on January 22, 1813. Some prisoners were taken to Detroit, but Procter left those too injured to travel with an inadequate guard. His Native American allies attacked and killed perhaps as many as 60 wounded Americans, many of whom were Kentucky militiamen. The Americans called the incident the "River Raisin Massacre." The defeat ended Harrison's campaign against Detroit, and the phrase "Remember the River Raisin!" became a rallying cry for the Americans.


title: Shawnee

text: In May 1813, Procter and Tecumseh besieged Fort Meigs in northern Ohio. American reinforcements arriving during the siege were defeated by the Natives, but the garrison in the fort held out. The Indians eventually began to disperse, forcing Procter and Tecumseh to return to Canada. Their second offensive in July against Fort Meigs also failed. To improve Indian morale, Procter and Tecumseh attempted to storm Fort Stephenson, a small American post on the Sandusky River. After they were repulsed with serious losses, the British and Tecumseh ended their Ohio campaign.


title: Shawnee

text: On Lake Erie, the American commander Captain Oliver Hazard Perry fought the Battle of Lake Erie on September 10, 1813. His decisive victory against the British ensured American control of the lake, improved American morale after a series of defeats, and compelled the British to fall back from Detroit. General Harrison launched another invasion of Upper Canada (Ontario), which culminated in the U.S. victory at the Battle of the Thames on October 5, 1813. Tecumseh was killed there, and his death effectively ended the North American indigenous alliance with the British in the Detroit region. American control of Lake Erie meant the British could no longer provide essential military supplies to their aboriginal allies, who dropped out of the war. The Americans controlled the area during the remainder of the conflict.


title: Shawnee

text: The Shawnee in Missouri migrated from the United States south into Mexico, in the eastern part of Spanish Texas. They became known as the "Absentee Shawnee." They were joined in the migration by some Delaware (Lenape). Although they were closely allied with the Cherokee led by The Bowl, their chief John Linney remained neutral during the 1839 Cherokee War.


title: Shawnee

text: Texas achieved independence from Mexico under American leaders. It decided to force removal of the Shawnee from the new republic. But in appreciation of their earlier neutrality, Texan President Mirabeau Lamar fully compensated the Shawnee for their improvements and crops. They were forced out to Arkansas Territory. The Shawnee settled close to present-day Shawnee, Oklahoma. They were joined by Shawnee pushed out of Kansas (see below), who shared their traditionalist views and beliefs.


title: Shawnee

text: In 1817, the Ohio Shawnee had signed the Treaty of Fort Meigs, ceding their remaining lands in exchange for three reservations in Wapaughkonetta, Hog Creek (near Lima), and Lewistown, Ohio. They shared these lands with some Seneca people who had migrated west from New York.


title: Shawnee

text: In a series of treaties, including the Treaty of Lewistown of 1825, Shawnee and Seneca people agreed to exchange land in western Ohio with the United States for land west of the Mississippi River in what became Indian Territory. In July 1831, the Lewistown group of Seneca–Shawnee departed for the Indian Territory (in present-day Kansas and Oklahoma).


title: Shawnee

text: The main body of Shawnee in Ohio followed Black Hoof, who fought every effort to force his people to give up their homeland. After the death of Black Hoof, the remaining 400 Ohio Shawnee in Wapaughkonetta and Hog Creek surrendered their land and moved to the Shawnee Reserve in Kansas. This movement was largely under terms negotiated by Joseph Parks (1793-1859). He had been raised in the household of Lewis Cass and had been a leading interpreter for the Shawnee.<ref name="Society https://archive.org/details/collectionskans00socigoog/page/n421 399"></ref>


title: Shawnee

text: Missouri joined the Union in 1821. After the Treaty of St. Louis in 1825, the 1,400 Missouri Shawnee were forcibly relocated from Cape Girardeau, along the west bank of the Mississippi River, to southeastern Kansas, close to the Neosho River.


title: Shawnee

text: During 1833, only Black Bob's band of Shawnee resisted removal. They settled in northeastern Kansas near Olathe and along the Kansas (Kaw) River in Monticello near Gum Springs. The Shawnee Methodist Mission was built nearby to minister to the tribe. About 200 of the Ohio Shawnee followed the prophet Tenskwatawa and had joined their Kansas brothers and sisters here in 1826.


title: Shawnee

text: In the mid-1830s two companies of Shawnee soldiers were recruited into United States service to fight in the Seminole War in Florida. One of these was led by Joseph Parks, who had earlier helped negotiate the cession treaty. He was commissioned as captain. Parks was a major landholder in both Westport, Missouri and in Shawnee, Kansas. He was also a Freemason and a member of the Methodist Episcopal Church. In Shawnee, Kansas, a Shawnee cemetery was started in the 1830s and remained in use until the 1870s. Parks was among the most prominent men buried there.


title: Shawnee

text: In the 1853 Indian Appropriations Bill, Congress appropriated $64,366 for treaty obligations to the Shawnee, such as annuities, education, and other services. An additional $2,000 was appropriated for the Seneca and the Shawnee together.


title: Shawnee

text: During the American Civil War, Black Bob's band fled from Kansas and joined the "Absentee Shawnee" in Indian Territory to escape the war. After the Civil War, the Shawnee in Kansas were expelled and forced to move to northeastern Oklahoma. The Shawnee members of the former Lewistown group became known as the "Eastern Shawnee".


title: Shawnee

text: The former Kansas Shawnee became known as the "Loyal Shawnee" (some say this is because of their allegiance with the Union during the war; others say this is because they were the last group to leave their Ohio homelands). The latter group appeared to be regarded as part of the Cherokee Nation by the United States. They were also known as the "Cherokee Shawnee" and were settled on some of the Cherokee land in Indian Territory.


title: Shawnee

text: In the late 20th century, the "Loyal" or "Cherokee" Shawnee began a movement to be federally recognized as a tribe independent of the Cherokee Nation. They received this action by a Congressional bill and are now known as the "Shawnee Tribe". Today, most members of the three federally recognized tribes of the Shawnee nation reside in Oklahoma.


title: Shawnee

text: Before contact with Europeans, the Shawnee tribe had a patrilineal system, by which descent and inheritance went through paternal lines. This was different from many of the Native American tribes, who had matrilineal kinship systems. In that alternative, children were considered born to the mother's family and clan, and inheritance and property was passed through the female line.


title: Shawnee

text: According to mid-19th century historian Henry Harvey, the Shawnee were ruled by kings, whom they called "sachema" [or sachems], who reigned by succession in the matrilineal line. For instance, the children of a king would not inherit the position. The sons of his brother, by the mother, or the sons of his sister (and after them, the sons of her daughter) would reign. Women did not inherit such a position directly. Harvey suggested that the Shawnee relied on this system of descent because a woman's sons would always be considered legitimate.


title: Shawnee

text: The war chiefs were also hereditary. They descended from their maternal line in the Kispoko division.


title: Shawnee

text: A 1935 study noted that the Shawnee had five septs, and that they were also divided among six clans or subdivisions, according to kinship. Each clan represented spiritual values and had a recognized role in the overall confederacy. Each name group or clan is found among each of the five divisions, and each Shawnee belongs to a clan or name group.


title: Shawnee

text: Each sept or division had a primary village where the chief of the division lived. This village was usually named after the division. By tradition, each Shawnee division and clan had certain roles it performed on behalf of the entire tribe. By the time these kinship elements were recorded in writing by European Americans, these strong social traditions were fading. They are poorly understood. Because of the disruption and scattering of the Shawnee people from the 17th century through the 19th century, the roles of the divisions changed.


title: Shawnee

text: Today the United States government recognizes three Shawnee tribes, all of which are located in Oklahoma:


title: Shawnee

text: The state of Alabama recognizes an organization, the Piqua Shawnee Tribe, as a state-recognized tribe under the Davis-Strong Act.


title: Yucca Mountain nuclear waste repository

text: The Yucca Mountain Nuclear Waste Repository, as designated by the Nuclear Waste Policy Act amendments of 1987, is a proposed deep geological repository storage facility within Yucca Mountain for spent nuclear fuel and other high-level radioactive waste in the United States. The site is on federal land adjacent to the Nevada Test Site in Nye County, Nevada, about northwest of the Las Vegas Valley.


title: Yucca Mountain nuclear waste repository

text: The project was approved in 2002 by the 107th United States Congress, but the 112th Congress ended federal funding for the site via amendment to the Department of Defense and Full-Year Continuing Appropriations Act, passed on April 14, 2011, during the Obama Administration. The project has encountered many difficulties and was highly contested by the public, the Western Shoshone peoples, and many politicians. The project also faces strong state and regional opposition. The Government Accountability Office stated that the closure was for political, not technical or safety reasons.


title: Yucca Mountain nuclear waste repository

text: This leaves the United States government (which disposes of its transuranic waste from nuclear weapons production below the surface at the Waste Isolation Pilot Plant in New Mexico) and American nuclear power plants without any designated long-term storage for their high-level radioactive waste (spent fuel) stored on-site in steel and concrete casks (dry cask storage) at 76 reactor sites in 34 states.


title: Yucca Mountain nuclear waste repository

text: Under President Barack Obama, the Department of Energy (DOE) reviewed options other than Yucca Mountain for a high-level waste repository. The Blue Ribbon Commission on America's Nuclear Future, established by the Secretary of Energy, released its final report in January 2012. It detailed an urgent need to find a site suitable for constructing a consolidated geological repository, stating that any future facility should be developed by a new independent organization with direct access to the Nuclear Waste Fund, which is not subject to political and financial control as the Cabinet-level DOE is. But the site met with strong opposition in Nevada, including from then-Senate leader Harry Reid.


title: Yucca Mountain nuclear waste repository

text: Under President Donald Trump, the DOE ceased deep borehole and other non–Yucca Mountain waste disposition research activities. For FY18, the DOE requested $120 million and the NRC $30 million from Congress to continue licensing activities for the Yucca Mountain Repository. For FY19, the DOE again requested $120 million but the NRC increased its request to $47.7 million. Congress decided to provide no funding for the remainder of FY18. In May 2019, Representative John Shimkus reintroduced a bill in the House for the site, but the Appropriation Committee killed an amendment by Representative Mike Simpson to add $74 million in Yucca Mountain funding to a DOE appropriations bill. On May 20, 2020, Under Secretary of Energy Mark W. Menezes testified in front of the Senate Energy and Natural Resources Committee that Trump strongly opposes proceeding with Yucca Mountain Repository.


title: Yucca Mountain nuclear waste repository

text: In May 2021, Energy Secretary Jennifer Granholm said that Yucca Mountain would not be part of the Biden administration's plans for nuclear-waste disposal. She anticipated announcing the department's next steps "in the coming months".


title: Yucca Mountain nuclear waste repository

text: Spent nuclear fuel is the radioactive by-product of electricity generation at commercial nuclear power plants, and high-level radioactive waste is the by-product of reprocessing spent fuel to produce fissile material for nuclear weapons. In 1982, Congress established a national policy to solve the problem of nuclear waste disposal. This policy is a federal law called the Nuclear Waste Policy Act, which made the U.S. Department of Energy (DOE) responsible for finding a site, building, and operating an underground disposal facility called a geologic repository. The recommendation to use a geologic repository dates to 1957, when the National Academy of Sciences recommended that the best way to protect the environment and public health and safety is to dispose of the waste in rock deep underground.


title: Yucca Mountain nuclear waste repository

text: The DOE began studying Yucca Mountain in 1978 to determine whether it would be suitable for the nation's first long-term geologic repository for over (150 million pounds) of spent nuclear fuel and high-level radioactive waste as of 2015 stored at 121 sites around the nation. An estimated of the waste would be from America's military nuclear programs.


title: Yucca Mountain nuclear waste repository

text: On December 19, 1984, the DOE selected ten locations in six states for consideration as potential repository sites, based on data collected for nearly ten years. The ten sites were studied and results of these preliminary studies were reported in 1985. Based on these reports, President Ronald Reagan approved three sites for intensive scientific study called site characterization. The three sites were Hanford, Washington; Deaf Smith County, Texas; and Yucca Mountain.


title: Yucca Mountain nuclear waste repository

text: In 1987, Congress amended the Nuclear Waste Policy Act and directed DOE to study only Yucca Mountain, which is adjacent to the former nuclear test site. The Act provided that if during site characterization Yucca Mountain was found unsuitable, studies would stop immediately. This option expired when Reagan actually recommended the site.


title: Yucca Mountain nuclear waste repository

text: On July 23, 2002, President George W. Bush signed House Joint Resolution 87, () allowing the DOE to take the next step in establishing a safe repository in which to store nuclear waste. The DOE was to begin accepting spent fuel at the Yucca Mountain Repository by January 31, 1998, but did not do so because of a series of delays due to legal challenges, concerns over how to transport nuclear waste to the facility, and political pressure resulting in underfunding of the construction.


title: Yucca Mountain nuclear waste repository

text: On July 18, 2006, the DOE proposed March 31, 2017, as the date to open the facility and begin accepting waste based on full funding. On September 8, 2006, Bush nominated Ward (Edward) Sproat, a nuclear industry executive formerly of PECO energy in Pennsylvania, to lead the Yucca Mountain Project. Following the 2006 midterm Congressional elections, Harry Reid, a longtime opponent of the repository, became the Senate Majority Leader, putting him in a position to greatly affect the future of the project. Reid said he would continue to work to block completion of the project, and is quoted as having said, "Yucca Mountain is dead. It'll never happen."


title: Yucca Mountain nuclear waste repository

text: In the 2008 Omnibus Spending Bill, the Yucca Mountain Project's budget was reduced to $390 million. The project was able to reallocate resources and delay transportation expenditures to complete the License Application for submission on June 3, 2008. During his 2008 presidential campaign, Barack Obama promised to abandon the project. After his election, the Nuclear Regulatory Commission told Obama he did not have the ability to do so. On April 23, 2009, Lindsey Graham and eight other senators introduced legislation to provide "rebates" from a $30 billion federally managed fund into which nuclear power plants had been paying, so as to refund all collected funds if Congress canceled the project.


title: Yucca Mountain nuclear waste repository

text: In November 2013, in response to a lawsuit filed by the National Association of Regulatory Utility Commissioners and the Nuclear Energy Institute, the US court of appeals ruled that nuclear utilities may stop paying into the nuclear waste recovery fund until either the DOE follows the Nuclear Waste Policy Act, which designates Yucca Mountain as the repository, or Congress changes the law. The fee ended May 16, 2014.


title: Yucca Mountain nuclear waste repository

text: Lacking an operating repository, the federal government initially paid utility companies somewhere between $300 and $500 million per year in compensation for failing to comply with the contract it signed to take the spent nuclear fuel by 1998. For the ten years after 2015 it is estimated to cost taxpayers $24 billion in payments from the Judgment Fund. The Judgment Fund is not subject to budget rules and allows Congress to ignore the nuclear waste issue since payments therefrom do not have any impact on yearly spending for other programs.


title: Yucca Mountain nuclear waste repository

text: The purpose of the Yucca Mountain project is to comply with the Nuclear Waste Policy Act of 1982 and develop a national site for spent nuclear fuel and high-level radioactive waste storage. The management and operating contractor as of April 1, 2009 for the project is USA Repository Services (USA-RS), a wholly owned subsidiary of URS Corporation (now part of AECOM) with supporting principal subcontractors Shaw Corporation (now part of McDermott International Inc.) and Areva Federal Services LLC (now Orano federal services business).


title: Yucca Mountain nuclear waste repository

text: After the layoff of 800 employees on March 31, 2009, about 100 employees remained on the project until all technical staff were laid off by the end of FY 2010 due to zero funding in the 2011 budget for the Office of Civilian Radioactive Waste Management. Sandia National Laboratories was responsible for post-closure analysis and ensuring compliance with the NWPA. The main tunnel of the Exploratory Studies Facility is U-shaped, long and wide.


title: Yucca Mountain nuclear waste repository

text: There are also several cathedral-like alcoves that branch from the main tunnel. Most of the scientific experiments were conducted in these alcoves. The emplacement drifts (smaller-diameter tunnels branching off the main tunnel) where waste would have been stored were not constructed since they required authorization from the Nuclear Regulatory Commission. The repository has a statutory limit of .


title: Yucca Mountain nuclear waste repository

text: To store that much waste would have required of tunnels. The Nuclear Waste Policy Act further limits the capacity of the repository to of initial heavy metal in commercial spent fuel. The 104 U.S. commercial reactors currently operating will produce this quantity of spent fuel by 2014, assuming that the spent fuel rods are not reprocessed. Currently, the US has no civil reprocessing plant.


title: Yucca Mountain nuclear waste repository

text: By 2008, Yucca Mountain was one of the most studied pieces of geology in the world; between geologic studies and materials science, the United States had invested US$9 billion on the project. This site studied by the Nevada Bureau of Mines and Geology (NBMG) differs substantially from other potential repositories due to the finding of natural analogues of nuclear material that are currently being studied. The DOE estimates that it has over 100 million U.S. gallons of highly radioactive waste and of spent fuel from the production of nuclear weapons and from research activities in temporary storage.


title: Yucca Mountain nuclear waste repository

text: The cost of the facility is being paid for by a combination of a tax on each kilowatt hour of nuclear power and by the taxpayers for disposal of weapons and naval nuclear waste. Based on the 2001 cost estimate, about 73% is funded by consumers of nuclear-powered electricity and 27% by the taxpayers.


title: Yucca Mountain nuclear waste repository

text: The Total System Life Cycle Cost Director Sproat presented to Congress on July 15, 2008, was $90 billion. This cost could not be compared to previous estimates since it included a repository capacity about twice as large as previously estimated over a much longer period of time (100 years vs. 30 years). Additionally, the cost of the project continued to escalate because of insufficient funding to most efficiently move forward and complete the project. By 2007, the DOE announced it was seeking to double the size of the Yucca Mountain repository to a capacity of , or 300 million pounds.


title: Yucca Mountain nuclear waste repository

text: The tunnel boring machine (TBM) that excavated the main tunnel cost $13 million and was long when in operation. It now sits at its exit point at the South Portal (south entrance) of the facility. The short side tunnel alcoves were excavated using explosives.


title: Yucca Mountain nuclear waste repository

text: The DOE was scheduled to begin accepting spent fuel at the Yucca Mountain repository by . By 2010, years after this deadline, the future status of the repository at Yucca Mountain was still unknown due to ongoing litigation, and opposition by Harry Reid.


title: Yucca Mountain nuclear waste repository

text: Because of construction delays, a number of nuclear power plants in the United States have resorted to dry cask storage of waste on-site indefinitely in steel and concrete casks.


title: Yucca Mountain nuclear waste repository

text: The project is widely opposed in Nevada and is a hotly debated national topic. A two-thirds majority of Nevadans feel it is unfair for their state to have to store nuclear waste when there are no nuclear power plants in Nevada. Many Nevadans' opposition stemmed from the so-called "Screw Nevada Bill," the 1987 legislation halting study of Hanford and Texas as potential sites for the waste before conclusions could be made. The county containing the proposed facility, Nye County, supports the repository's development, as do six adjoining counties. A 2015 survey of Nevadans found 55% agreeing that the state should be open to discussion of what benefits could be received.


title: Yucca Mountain nuclear waste repository

text: One point of concern has been the standard of radiation emission in 10,000 to 1,000,000 years. On August 9, 2005, the United States Environmental Protection Agency (EPA) proposed a limit of 350 millirem per year for that period. In October 2007, the DOE issued a draft of the Supplemental Environmental Impact Statement showing that for the first 10,000 years mean public dose would be 0.24 mrem/year and that thereafter the median public dose would be 0.98 mrem/year, both of which are substantially below the proposed EPA limit. For comparison, a hip X-ray results in a dose around 83 mrem and a CT head or chest scan results in around 1,110 mrem. Annually, in the United States, an individual's dose from background radiation is about 350 mrem, though some places get more than twice that.


title: Yucca Mountain nuclear waste repository

text: On February 12, 2002, Secretary of Energy Spencer Abraham decided that this site was suitable to be the nation's nuclear repository. The governor of Nevada had 90 days to object and did so, but Congress overrode the objection. If the governor's objection had stood, the project would have been abandoned and a new site chosen. In August 2004, the repository became an election issue when Senator John Kerry said he would abandon the plans if elected.


title: Yucca Mountain nuclear waste repository

text: In March 2005, the Energy and Interior departments revealed that several U.S. Geological Survey hydrologists had exchanged emails discussing possible falsification of quality assurance documents on water infiltration research. On February 17, 2006, the DOE's Office of Civilian Radioactive Waste Management (OCRWM) released a report confirming the technical soundness of infiltration modeling work performed by U.S. Geological Survey (USGS) employees. In March 2006, the U.S. Senate Committee on Environment and Public Works Majority Staff issued a 25-page white paper, "Yucca Mountain: The Most Studied Real Estate on the Planet." The conclusions were:


title: Yucca Mountain nuclear waste repository

text: On January 18, 2006, DOE OCRWM announced that it would designate Sandia National Laboratories as its lead laboratory to integrate repository science work for the Yucca Mountain Project. "We believe that establishing Sandia as our lead laboratory is an important step in our new path forward. The independent, expert review that the scientists at Sandia will perform will help ensure that the technical and scientific basis for the Yucca Mountain repository is without question," OCRWM's Acting Director Paul Golan said. "Sandia has unique experience in managing scientific investigations in support of a federally licensed geologic disposal facility, having served in that role as the scientific advisor to the Waste Isolation Pilot Plant in Carlsbad, New Mexico." Sandia began acting as the lead laboratory on October 1, 2006.


title: Yucca Mountain nuclear waste repository

text: Because of questions raised by the State of Nevada and Congressional members about the quality of the science behind Yucca Mountain, the DOE announced on March 31, 2006, the selection of Oak Ridge Associated Universities/Oak Ridge Institute for Science and Education (a not-for-profit consortium that includes 96 doctoral degree-granting institutions and 11 associate member universities) to provide expert reviews of scientific and technical work on the Yucca Mountain Project. DOE stated that the project "will be based on sound science. By bringing in Oak Ridge for review of technical work, DOE will seek to present a high level of expertise and credibility as they move the project forward ... This award gives DOE access to academic and research institutions to help DOE meet their mission and legal obligation to license, construct, and open Yucca Mountain as the nation's repository for spent nuclear fuel."


title: Yucca Mountain nuclear waste repository

text: There was significant public and political opposition to the project in Nevada. An attempt was made to push ahead with it and override the opposition. But for large projects that would take decades to complete, there is every chance that sustained local opposition will prevail, and this happened with the Yucca Mountain project. Successful nuclear waste storage siting efforts in Scandinavia have involved local communities in the decision-making process and given them a veto at each stage, but this did not happen with Yucca Mountain. Local communities at potential storage and repository sites "should have early and continued involvement in the process, including funding that would allow them to retain technical experts".


title: Yucca Mountain nuclear waste repository

text: On March 5, 2009, Energy Secretary Steven Chu reiterated in a Senate hearing that the Yucca Mountain site was no longer considered an option for storing reactor waste.


title: Yucca Mountain nuclear waste repository

text: On March 3, 2010, the DOE filed a motion with the NRC to withdraw its license application, but multiple lawsuits to stop this action have been filed by states, counties, and individuals across the country as being unauthorized by the NWPA.


title: Yucca Mountain nuclear waste repository

text: The costly nuclear accident in 2014 at New Mexico's Waste Isolation Pilot Plant in which a nuclear waste container exploded has caused doubt that it could serve as an alternative for Yucca.


title: Yucca Mountain nuclear waste repository

text: In January 2019, Governor Steve Silolak vowed that "not one ounce" of nuclear waste would be allowed at Yucca Mountain, and a May funding bill did not include funding for the site. In May 2019, the Reno Gazette-Journal published a long-form essay cataloging opposition to the Yucca Mountain project. According to a tribal elder, the Western Shoshone view Yucca Mountain as sacred and a nuclear storage facility "will poison everything. It's people's life, our Mother Earth's life, all the living things here, all the creatures; whatever's crawling around, it's their life too." The tribes say they lack funds to discredit federal safety claims, but will be directly affected by a potential disaster.


title: Yucca Mountain nuclear waste repository

text: The EPA established its Yucca Mountain standards in June 2001. The storage standard set a dose limit of 15 millirem per year for the public outside the Yucca Mountain site. The disposal standards consisted of three components: an individual dose standard, a standard evaluating the impacts of human intrusion into the repository, and a groundwater protection standard. The individual-protection and human intrusion standards set a limit of 15 millirem per year to a reasonably maximally exposed individual, who would be among the most highly exposed members of the public.


title: Yucca Mountain nuclear waste repository

text: The groundwater protection standard is consistent with EPA's Safe Drinking Water Act standards, which the Agency applies in many situations as a pollution prevention measure. The disposal standards were to apply for 10,000 years after the facility is closed. Dose assessments were to continue beyond 10,000 years and be placed in DOE's Environmental Impact Statement, but were not subject to a compliance standard.


title: Yucca Mountain nuclear waste repository

text: The 10,000-year period for compliance assessment is consistent with EPA's generally applicable standards developed under the Nuclear Waste Policy Act. It also reflects international guidance regarding the level of confidence that can be placed in numerical projections over very long periods of time.


title: Yucca Mountain nuclear waste repository

text: Shortly after the EPA first established these standards in 2001, the nuclear industry, several environmental and public interest groups, and the State of Nevada challenged the standards in court. In July 2004, the Court of Appeals for the District of Columbia Circuit found in favor of the Agency on all counts except one: the 10,000 year regulatory time frame. The court ruled that EPA's 10,000-year compliance period for isolation of radioactive waste was not consistent with National Academy of Sciences (NAS) recommendations and was too short.


title: Yucca Mountain nuclear waste repository

text: The NAS report had recommended standards be set for the time of peak risk, which might approach a period of one million years. By limiting the compliance time to 10,000 years, EPA did not respect a statutory requirement that it develop standards consistent with NAS recommendations.


title: Yucca Mountain nuclear waste repository

text: EPA published in the Federal Register a final rule in 2009. The new rule limits radiation doses from Yucca Mountain for up to 1,000,000 years after it closes. Within that regulatory time frame, the EPA has two dose standards that would apply based on the number of years from the time the facility is closed.


title: Yucca Mountain nuclear waste repository

text: For the first 10,000 years, the EPA would retain the 2001 final rule's dose limit of 15 millirem per year. This is protection at the level of the most stringent radiation regulations in the U.S. today. From 10,000 to one million years, EPA established a dose limit of 100 millirem per year. EPA's rule requires DOE to show that Yucca Mountain can safely contain wastes, considering the effects of earthquakes, volcanic activity, climate change, and container corrosion, over one million years. The current analysis indicates that the repository will cause less than 1 mrem/year public dose for 1,000,000 years.


title: Yucca Mountain nuclear waste repository

text: The formation that makes up Yucca Mountain was created by several large eruptions from a caldera volcano and is composed of alternating layers of ignimbrite (welded tuff), non-welded tuff, and semi-welded tuff. The tuff surrounding the burial sites is expected to protect human health as it provides a natural barrier to the radiation. It lies along the transition between the Mojave and the Great Basin Deserts.


title: Yucca Mountain nuclear waste repository

text: The volcanic tuff at Yucca Mountain is appreciably fractured and movement of water through an aquifer below the waste repository is primarily through fractures. While the fractures are usually confined to individual layers of tuff, the faults extend from the planned storage area all the way to the water table below the surface. Future water transport from the surface to waste containers is likely to be dominated by fractures. There is evidence that surface water has been transported down through the of overburden to the exploratory tunnel at Yucca Mountain in less than 50 years.


title: Yucca Mountain nuclear waste repository

text: The aquifer of Yucca Mountain drains to Amargosa Valley, home to over 1400 people and a number of endangered species.


title: Yucca Mountain nuclear waste repository

text: Some site opponents assert that, after the predicted containment failure of the waste containers, these cracks may provide a route for movement of radioactive waste that dissolves in the water flowing downward from the desert surface. Officials state that the waste containers will be stored in such a way as to minimize or even nearly eliminate this possibility.


title: Yucca Mountain nuclear waste repository

text: The area around Yucca Mountain received much more rain in the geologic past and the water table was consequently much higher than it is today, though well below the level of the repository.


title: Yucca Mountain nuclear waste repository

text: DOE has stated that seismic and tectonic effects on the natural systems at Yucca Mountain will not significantly affect repository performance. Yucca Mountain lies in a region of ongoing tectonic deformation, but the deformation rates are too slow to significantly affect the mountain during the 10,000-year regulatory compliance period. Rises in the water table caused by seismic activity would be, at most, a few tens of meters and would not reach the repository. The fractured and faulted volcanic tuff that Yucca Mountain comprises reflects the occurrence of many earthquake-faulting and strong ground motion events during the last several million years, and the hydrological characteristics of the rock would not be changed significantly by seismic events that may occur in the next 10,000 years. The engineered barrier system components will reportedly provide substantial protection of the waste from seepage water, even under severe seismic loading.


title: Yucca Mountain nuclear waste repository

text: In September 2007, it was discovered that the Bow Ridge fault line ran underneath the facility, hundreds of feet east of where it was originally thought to be located, beneath a storage pad where spent radioactive fuel canisters would be cooled before being sealed in a maze of tunnels. The discovery required several structures to be moved several hundred feet further to the east, and drew criticism from Robert R. Loux, then head of the Nevada Agency for Nuclear Projects, who argues that Yucca administrators should have known about the fault line's location years prior, and called the movement of the structures "just-in-time engineering."


title: Yucca Mountain nuclear waste repository

text: In June 2008, a major nuclear equipment supplier, Holtec International, criticized DOE's safety plan for handling containers of radioactive waste before they are buried at the proposed Yucca Mountain dump. The concern is that, in an earthquake, the unanchored casks of nuclear waste material awaiting burial at Yucca Mountain could be sent into a "chaotic melee of bouncing and rolling juggernauts".


title: Yucca Mountain nuclear waste repository

text: The nuclear waste was planned to be shipped to the site by rail and/or truck in robust containers known as spent nuclear fuel shipping casks, approved by the Nuclear Regulatory Commission. While the routes in Nevada would have been public, in the other states the planned routes, dates and times of transport would have been secret for security reasons. State and tribal representatives would have been notified before shipments of spent nuclear fuel entered their jurisdictions.


title: Yucca Mountain nuclear waste repository

text: Within Nevada, the planned primary mode of transportation was via rail through the Caliente Corridor. This corridor starts in Caliente, Nevada, traveling along the northern and western borders of the Nevada Test Site for approximately . At this point, it turns south.


title: Yucca Mountain nuclear waste repository

text: Other options that were being considered included a rail route along the Mina corridor. This rail route would have originated at the Fort Churchill Siding rail line, near Wabuska. The proposed corridor would have proceeded southeast through Hawthorne, Blair Junction, Lida Junction and Oasis Valley. At Oasis Valley, the rail line would have turned north-northeast towards Yucca Mountain. Use of this rail corridor by DOE would have required permission from the Walker River Paiute Tribe in order to cross their land. As the first of the proposed corridor was owned by the Department of Defense (DoD), additional permission from the DoD would have to have been granted.


title: Yucca Mountain nuclear waste repository

text: The Nevada Center for Biological Diversity and the Nevada Attorney General both have expressed concern about the transportation routes, "through any number of sensitive habitats."


title: Yucca Mountain nuclear waste repository

text: Since the early 1960s, the U.S. has safely conducted more than 3,000 shipments of spent nuclear fuel without any harmful release of radioactive material. This safety record is comparable to the worldwide experience where more than 70,000 metric tons of spent nuclear fuel have been transported since 1970 – an amount approximately equal to the total amount of spent nuclear fuel that would have been shipped to Yucca Mountain.


title: Yucca Mountain nuclear waste repository

text: But cities were still concerned about the transport of radioactive waste on highways and railroads that may have passed through heavily populated areas. Dr. Robert Halstead, a transportation adviser to the state of Nevada since 1988, said of transportation of the high-level waste, "They would heavily affect cities like Buffalo, Cleveland, Pittsburgh, in the Chicago metropolitan area, in Omaha." "Coming out of the south, the heaviest impacts would be in Atlanta, in Nashville, St. Louis, Kansas City, moving across through Salt Lake City, through downtown Las Vegas, up to Yucca Mountain. And the same cities would be affected by rail shipments as well." Spencer Abraham (DOE) said, "I think there's a general understanding that we move hazardous materials in this country, an understanding that the federal government knows how to do it safely."


title: Yucca Mountain nuclear waste repository

text: In October 2018, a state senator from Utah argued that transferring nuclear waste from other states to Yucca Mountain on state highways and railways could be a health hazard.


title: Yucca Mountain nuclear waste repository

text: Archaeological surveys have found evidence that Native Americans used the immediate vicinity of Yucca Mountain on a temporary or seasonal basis. Some Native Americans disagree with the conclusions of archaeological investigators that their ancestors were highly mobile groups of hunter-gatherers who occupied the Yucca Mountain area before Euroamericans began using the area for prospecting, surveying, and ranching. They believe that these conclusions overlook traditional accounts of farming that occurred before European contact.


title: Yucca Mountain nuclear waste repository

text: Yucca Mountain and surrounding lands were central in the lives of the Southern Paiute, Western Shoshone, and Owens Valley Paiute and Shoshone peoples, who shared them for religious ceremonies, resource uses, and social events.


title: Yucca Mountain nuclear waste repository

text: Starting in 2009, the Obama administration attempted to close the Yucca Mountain repository, despite current US law that designates Yucca Mountain as the nation's nuclear waste repository. The administration agency, DOE, began implementation of the President's plan in May 2009. The Nuclear Regulatory Commission also went along with the administration's closure plan. Various state and Congressional entities attempted to challenge the administration's closure plans, by statute and in court.


title: Yucca Mountain nuclear waste repository

text: Most recently, in August 2013, a US Court of Appeals decision told the NRC and the Obama administration that they must either "approve or reject [DOE's] application for [the] never-completed waste storage site at Nevada's Yucca Mountain." They cannot simply make plans for its closure in violation of US law.


title: Yucca Mountain nuclear waste repository

text: In 2008, the U.S. Senate Committee on Environmental and Public Works found that failure to perform to contractual requirements could cost taxpayers up to $11 billion by 2020. In 2013 this estimate of taxpayer liability was raised to $21 billion. In July 2009, the House of Representatives voted 388 to 30 on amendments to HHR3183 () to not defund the Yucca Mountain repository in the FY2010 budget. In 2013, the House of Representatives voted twice during the 2014 Energy and Water Appropriations debate by over 80% majority to reject elimination of Yucca Mountain as the nation's only nuclear waste solution.


title: Yucca Mountain nuclear waste repository

text: On April 13, 2010, the state of Washington filed suit to prevent the closing of Yucca Mountain, since this would slow efforts to clean up Hanford Nuclear Reservation. South Carolina, Aiken County (the location of Savannah River site) and others joined Washington. The United States Court of Appeals for the District of Columbia Circuit dismissed the suit in July 2011, saying the Nuclear Regulatory Commission had not ruled on the withdrawal of the license application. Washington and South Carolina filed another lawsuit on July 29.


title: Yucca Mountain nuclear waste repository

text: With $32 billion received from power companies to fund the project, and $12 billion spent to study and build it, the federal government had $27 billion left, including interest. In March 2012, Senator Lindsey Graham introduced a bill requiring three-fourths of that money to be given back to customers, and the remainder to the companies for storage improvements.


title: Yucca Mountain nuclear waste repository

text: In August 2013, the U.S. Court of Appeals for the District of Columbia ordered the Nuclear Regulatory Commission to either "approve or reject [DOE's] application for [the] never-completed waste storage site at Nevada's Yucca Mountain." The court opinion said that the NRC was "simply flouting the law" in its previous action to allow the Obama administration to continue plans to close the proposed waste site since a federal law designating Yucca Mountain as the nation's nuclear waste repository remains in effect. The court opinion stated that "The president may not decline to follow a statutory mandate or prohibition simply because of policy objections."


title: Yucca Mountain nuclear waste repository

text: In response, NRC issued the final volumes of the Yucca Mountain Safety Evaluation Report (SER), which included the NRC staff's statement that the site would meet all applicable standards. At the same time, the staff also stated that NRC should not authorize construction of the repository until the requirements for land and water rights were met and a supplement to DOE's environmental impact statement (EIS) was finished. On March 3, 2015, NRC ordered the staff to complete the supplemental EIS and make the Yucca Mountain licensing document database publicly available, using all the remaining previously appropriated licensing funds.


title: Yucca Mountain nuclear waste repository

text: In March 2015, Senator Lamar Alexander introduced the Nuclear Waste Administration Act of 2015 (S854) in the U.S. Senate. It was intended to establish a fully independent Nuclear Waste Administration (NWA) that would develop nuclear waste storage and disposal facilities. Construction of such facilities would require the consent of the state, local, and tribal governments that may be affected. The NWA would be required to complete a mission plan to open a pilot storage facility by 2021 for nuclear waste from non-operating reactors and other "emergency" deliveries (called "priority waste").


title: Yucca Mountain nuclear waste repository

text: The goal would be to have a storage facility for waste from operating reactors or other "non-priority waste" available by 2025, and an actual permanent repository by the end of 2048. The current disposal limit of 70,000 metric tons for the nation's initial permanent repository would be repealed. Any nuclear waste fees collected after S854 was enacted would be held in a newly established Working Capital Fund. The Nuclear Waste Administration would be allowed to draw from that fund any amounts needed to carry out S.854, unless limited by annual appropriations or authorizations. S854 died in committee.


title: Yucca Mountain nuclear waste repository

text: On March 15, 2017, the Trump Administration announced it would request Congressional approval for $120 million to restart licensing activity at the Yucca Mountain repository, with funding also to be used to create an interim storage program. The project would consolidate nuclear waste across the United States in Yucca Mountain, which had been stockpiled in local locations since 2010. The federal budget proposal was refused by Senate. Although his administration had allocated money to the project, in October 2018, President Donald Trump stated he opposed the use of Yucca mountain for dumping, saying he agreed "with the people of Nevada."


title: Yucca Mountain nuclear waste repository

text: On May 11, 2018, the bill H.R. 3053 was approved in a 340–72 vote in the House of Representatives. The bill directed the DOE to resume the licensing process for Yucca Mountain, with licensing for a permanent site at the mountain to "take up to five years." The Nuclear Waste Policy Amendments Act was sponsored by John Shimkus. "The Hill" clarified that the bill would "set a path forward for the DOE to resume the process of planning for and building the southern Nevada site, transfer land to the DOE for it, ease the federal funding mechanism and allow DOE to build or license a temporary site to store waste while the Yucca project is being planned and built."


title: Yucca Mountain nuclear waste repository

text: The bill would "direct [DOE] to revive the licensing process for Yucca Mountain to be designated as the country’s permanent site for nuclear waste." The bill would bring together waste from 121 locations in 39 states. All Nevada representatives opposed the bill. The measure was scheduled to go to the Senate next, and if passed there, would require the Nuclear Regulatory Commission to decide on the matter within 30 months.


title: Yucca Mountain nuclear waste repository

text: "The Hill" noted that the bill received widespread support from lawmakers arguing that nuclear waste was best transferred out of their districts to Yucca, a concept opposed by Nevada representatives, with politicians such as Dina Titus dubbing it the "Screw Nevada 2.0" bill. Titus proposed an amendment that would have required long-term storage to be kept in locales that consented, which the House rejected, 332–80. In their opposition to the use of Yucca Mountain as a nuclear repository, Nevada representatives were supported by Dianne Feinstein of California and other politicians.


title: Yucca Mountain nuclear waste repository

text: In June 2018, the Trump administration and some members of Congress again began proposing using Yucca Mountain, with Nevada Senators raising opposition. By early 2019, use of Yucca Mountain was in "political limbo" as opposition to the site led to an impasse. In January 2019, a panel of scientists introduced to Congress a 126-page report, "Reset of America’s Nuclear Waste Management", which proposed including Yucca Mountain as a potential repository with "development of a consensus-based siting process, but one that would still include Yucca Mountain as a candidate."


title: Yucca Mountain nuclear waste repository

text: Nevada National Security Site officials in April 2019 assured the public that the Device Assembly Facility on the Nevada security site was safe from earthquake threats. In contrast, Nevada officials claimed seismic activity in the region made it unsafe for the storage of nuclear waste. On April 1, 2019, the "Las Vegas Review-Journal" noted that "Nevada Democrats in the House" were seeking to block transfers of plutonium from DOE into the state by the use of the appropriations process.


title: Equidae

text: Equidae (sometimes known as the horse family) is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. All extant species are in the genus "Equus", which originated in North America. Equidae belongs to the order Perissodactyla, which includes the extant tapirs and rhinoceros, and several extinct families.


title: Equidae

text: The oldest known fossils assigned to Equidae were found in North America, and date from the early Eocene epoch, 54 million years ago. They were once assigned to the genus "Hyracotherium", but the type species of that genus is now regarded as a palaeothere. The other species have been split off into different genera. These early equids were fox-sized animals with three toes on the hind feet, and four on the front feet. They were herbivorous browsers on relatively soft plants, and already adapted for running. The complexity of their brains suggest that they already were alert and intelligent animals. Later species reduced the number of toes, and developed teeth more suited for grinding up grasses and other tough plant food.


title: Equidae

text: The equids, like other perissodactyls, are hindgut fermenters. They have evolved specialized teeth that cut and shear tough plant matter to accommodate their fibrous diet. Their seemingly inefficient digestion strategy is a result of their size at the time of its evolution, as they would have already had to be relatively large mammals to be supported on such a strategy.


title: Equidae

text: The family became relatively diverse during the Miocene epoch, with many new species appearing. By this time, equids were more truly horse like, having developed the typical body shape of the modern animals. Many of these species bore the main weight of their bodies on their central third toe, with the others becoming reduced and barely touching the ground, if at all. The sole surviving genus, "Equus", had evolved by the early Pleistocene epoch, and spread rapidly through the world.


title: Jophiel

text: The angel Jophiel (Heb. "Yōp̄īʾēl", "God is my beauty"), also called "Iophiel", "Iofiel", "Jofiel", "Yofiel", "Youfiel", Zophiel ( "Ṣōp̄īʾēl", "God is my watchman") and Zuriel ( "Ṣūrīʾēl", "God is my rock"), is a non-canonical archangel of wisdom, understanding, and judgment, art and beauty. She is listed as one of the Seven Archangels in Pseudo-Dionysian teachings. Due to the association with beauty, Jophiel is one of very few angels to be sometimes portrayed as female. However, many angels have no canonical gender, and are most commonly referred to by male pronouns.


title: Jophiel

text: According to the pseudepigraphal Revelation of Moses, another name for Jophiel is Dina (Hebrew: דִּינָה "Dīnā", "Judgement"). In the text, Jophiel/Dina is described as an angel of the seventh heaven, a Cabalistic guardian of the Torah (and wisdom itself), who taught 70 languages to souls at the dawn of creation. The Zohar lists her as a Great Angel Chief in charge of 53 legions who superintend Torah-readings on the Sabbath. Jophiel is said to be a companion to the angel Metatron.


title: Jophiel

text: C.E. Clement, in her book "Angels in Art", names Jophiel as the teacher of Ham, Japheth, and Shem. Heinrich Cornelius Agrippa and Thomas Rudd likewise name Jophiel as the teacher of Shem.


title: Jophiel

text: In the Anglican tradition, Jophiel is recognized as an archangel. She is often depicted in iconography holding a flaming sword, such as the stained glasses at St Michael's Church in Brighton, St Peter and St John's Church in Kirkley, Holy Trinity Church in Coventry and a mural at St. John's Episcopal Church in Memphis, Tennessee.


title: Jophiel

text: Jophiel is an Archangel of the Kabbalah (though some systems put Raziel in her place) and in several listings including that of the early medieval theologian Pseudo-Dionysus. The Calendarium Naturale Magicum Perpetuum lists Jophiel as the angel of the Sephira Chokhmah, as do the Key of Solomon variant "The Veritable Clavicles of Solomon," and the Sixth and Seventh Books of Moses, both latter works derived from the "Calendarium". Agrippa attributes Jophiel to Saturn, while Paracelsus assigns her to Jupiter. Rudd attributes the Zodiac to Jophiel along with the Sephira Binah instead of Zaphkiel. Athanasius Kircher names Jophiel as , "angel of beauty". According to Robert Ambelain, Jophiel is in charge of the Cherubim, particularly the Shemhamphorasch angels Haziel, Aladiah, Lauviah, Hahaiah, Iezalel, Mehahel, Hariel, and Hakamiah.


title: Jophiel

text: "Angels of Love and Light" describes her as "the Archangel of Paradise and the Patron of Artists and Illumination. She teaches the outer consciousness the Power of Light within oneself. She is also described as "the Yellow Ray of Wisdom, Illumination, and Constancy", and lists her "Archeia" as Christine also says


title: Jophiel

text: John Milton, in his poem Paradise Lost, mentions that Zophiel is "of cherubim the swiftest wing" ("Paradise Lost" VI, 535).


title: Operation Ten-Go

text: , also known as Operation Heaven One (or Ten-ichi-gō 天一号), was the last major Japanese naval operation in the Pacific Theater of World War II. The resulting engagement is also known as the Battle of the East China Sea.


title: Operation Ten-Go

text: In April 1945, the , the largest battleship in the world, and nine other Japanese warships, embarked from Japan for a suicide attack on Allied forces engaged in the Battle of Okinawa. The Japanese force was attacked by U.S. carrier-borne aircraft before it could reach Okinawa. "Yamato" and five other Japanese warships were sunk.


title: Operation Ten-Go

text: The battle demonstrated U.S. air supremacy in the Asiatic-Pacific Theater and the vulnerability of surface ships without air cover to aerial attack. The battle also exhibited Japan's willingness to make extreme sacrifices in "kamikaze" attacks aimed at slowing the Allied advance on the Japanese home islands.


title: Operation Ten-Go

text: By early 1945, following the Solomon Islands campaign, the Battle of the Philippine Sea and the Battle of Leyte Gulf, the once-formidable Imperial Japanese Navy's Combined Fleet was reduced to just a handful of operational warships and a few remaining aircraft and aircrew. Most of the remaining Japanese warships in the Combined Fleet were stationed at ports in Japan, with most of the large ships at the port of Kure in the Hiroshima Prefecture on the main Japanese island of Honshu.


title: Operation Ten-Go

text: As a final step before the planned invasion of the Japanese home islands, Allied forces invaded Okinawa on 1 April 1945. In March, when briefing Emperor Hirohito on Japan's response to the expected invasion of Okinawa, Japanese military leaders explained that the Imperial Japanese Army was planning extensive air attacks, including the use of "kamikaze" tactics. The emperor then reportedly asked, "But what about the Navy? What are they doing to assist in defending Okinawa? Have we no more ships?" Now feeling pressured by the emperor to also mount some kind of attack, Japanese Navy commanders conceived a "kamikaze"-type mission for their remaining operational large ships, which included the battleship .


title: Operation Ten-Go

text: The resulting plan—drafted under the direction of the Commander-in-Chief of the Combined Fleet, Admiral Soemu Toyoda,—called for "Yamato" and her escorts to attack the U.S. fleet supporting the U.S. troops landing on the western coast of Okinawa. "Yamato" and her escorts were to fight their way to Okinawa and then beach themselves between Higashi and Yomitan and fight as shore batteries until they were destroyed. Once the ships were destroyed, their surviving crew members were supposed to abandon ship and fight U.S. forces on land. Very little, if any, air cover could be provided for the ships, which would render them almost helpless to concentrated attacks from U.S. carrier-based aircraft. In preparation for executing the plan, on 29 March the assigned ships left Kure for Tokuyama, off the port of Mitajiri on the southern coast of Honshu. Despite obeying orders to prepare for the mission, the commander of the "Ten-Go" force, Vice-Admiral Seiichi Itō, still refused to actually order his ships to carry it out, believing the plan to be futile and wasteful.


title: Operation Ten-Go

text: Other officers of the Imperial Japanese Navy also had very negative views about the operation, believing that it was a waste of human life and fuel. Captain Atsushi Ōi, an operations officer at Grand Escort Command, was critical as fuel and resources were diverted from other operations. As he was told that the aim of this operation was "the tradition and the glory of the Navy," he shouted: "this war is of our nation and why should the honor of our 'surface fleet' be more respected? Who cares about their glory? Damn fools!".


title: Operation Ten-Go

text: Vice Admiral Ryūnosuke Kusaka flew from Tokyo to Tokuyama on 5 April in a final attempt to convince Itō and the assembled commanders of the Combined Fleet to accept the plan. Upon hearing of the proposed operation—which had been kept secret from most of them—the Combined Fleet commanders and captains unanimously joined Itō in rejecting it for the same reasons that he had expressed. Kusaka then explained that the Navy's attack would help divert U.S. aircraft away from the Army's planned kamikaze attacks on the U.S. fleet at Okinawa. He also explained that Japan's national leadership, including the emperor, were expecting the Navy to make their best effort to support the defense of Okinawa.


title: Operation Ten-Go

text: Upon hearing this, the Combined Fleet commanders relented and accepted the proposed plan. The ships' crews were briefed on the nature of the mission and given the opportunity to stay behind if desired; none did. However, approximately 80 crew members who were new, sick, or infirm, were ordered off the ships, including sixty-seven naval cadets of Etajima Naval Academy Class No. 74 who had arrived on the battleship three days earlier. The ships' crews now engaged in some last-minute intense drills to prepare for the mission, mostly practicing damage control procedures. At midnight, the ships were fueled. Reportedly, in secret defiance of orders to provide the ships with only just enough fuel to reach Okinawa, the Tokuyama personnel actually gave "Yamato" and the other ships almost all of the remaining fuel in the port, although this probably still was not enough to allow the force to return to Japan from Okinawa. "Yamato"s executive officer organised a party for the crew for the evening of 5 April, during which many of the officers and sailors drank heavily.


title: Operation Ten-Go

text: The United States Navy was able to monitor preparations for Operation Ten-Go by decoding Japanese radio signals. Through this source, the Americans received conclusive intelligence on 5 and 6 April that the attack was to be attempted. The commander of the United States Fifth Fleet, Admiral Raymond Spruance, ordered his forces to prepare to attack the Japanese at 12:30 am on 6 April, before "Yamato" and her consorts sailed.


title: Operation Ten-Go

text: At 16:00 on 6 April, "Yamato" (with Admiral Itō on board), the light cruiser , and eight destroyers "(Asashimo, Hamakaze, Isokaze, Suzutsuki, Hatsushimo, Yukikaze, Fuyutsuki," and "Kasumi") departed Tokuyama to begin the mission. Two American submarines, and , sighted the Japanese force as it proceeded south through the Bungo Channel. Although they were unable to attack due to the ships' speed, they did spend several hours shadowing the Japanese sortie and sending updates on its course to the U.S. fleet. The submarines' messages, which were reportedly sent uncoded, were also picked up by radio operators on the Japanese ships.


title: Operation Ten-Go

text: At dawn on 7 April, the Japanese force passed the Ōsumi Peninsula into the open ocean heading south from Kyūshū toward Okinawa. They shifted into a defensive formation, with "Yahagi" leading "Yamato" and the eight destroyers deployed in a ring around the two larger ships, with each ship from each other and proceeding at . One of the Japanese destroyers, "Asashimo", developed engine trouble and turned back. U.S. reconnaissance aircraft began to shadow the main force of ships. At 10:00, the Japanese force turned west to make it look like they were withdrawing, but at 11:30, after being detected by two American PBM Mariner flying boats, the "Yamato" fired a salvo with her bow guns using special , but could not prevent the two planes from shadowing the Japanese force. Then they turned back towards Okinawa.


title: Operation Ten-Go

text: Upon receiving contact reports early on 7 April, Spruance ordered Task Force 54, which consisted mostly of modernized Standard-type battleships under the command of Rear Admiral Morton Deyo (which were engaged in shore bombardment), to intercept and destroy the Japanese sortie. Deyo moved to execute his orders, but Vice Admiral Marc A. Mitscher, who commanded Task Force 58, preempted Spruance and Deyo by launching a massive air strike from his carriers, without informing Spruance until after the launches were completed. As a senior naval aviation officer, "Mitscher had spent a career fighting the battleship admirals who had steered the navy’s thinking for most of the current century. One of those was his immediate superior, Raymond Spruance. Mitscher felt a stirring of battleship versus aircraft carrier rivalry. Though the carriers had mostly fought the great battles of the Pacific, whether air power alone could prevail over a surface force had not been proven beyond all doubt. Here was an opportunity to end the debate forever".


title: Operation Ten-Go

text: Around 10:00 on 7 April, Task Groups 58.1 and 58.3 began launching 280 aircraft from their carriers to attack the Japanese force. Task Group 58.4 launched a further 106 aircraft. The aircraft consisted of F6F Hellcat and F4U Corsair fighters, SB2C Helldiver dive bombers, and TBF Avenger torpedo bombers. Overall, 15 carriers launched aircraft. The air groups launched from five carriers became lost in bad weather and were not able to attack. As a contingency, Spruance ordered Admiral Deyo to assemble a force of six fast battleships, seven cruisers and 21 destroyers to prepare for a surface engagement with "Yamato" should the airstrikes prove unsuccessful.


title: Operation Ten-Go

text: Around noon, the first American aircraft arrived over "Yamato"; these were F6F Hellcat and F4U Corsair fighters, under orders to deal with any Japanese aircraft that might appear to defend the below-mentioned ships, but none appeared. Once it became obvious that the Japanese force had no air cover, the U.S. aircraft could set up for their attacks without fear of opposition from Japanese aircraft. U.S. bomber and torpedo aircraft arriving over the "Yamato" group—after their two-hour flight from Okinawa— could circle the Japanese ship formation just out of anti-aircraft range to set up their attacks on the warships below methodically. The first wave of U.S. carrier planes was spotted by a Japanese lookout on the bridge at 12:32. Two minutes later, at 12:34, "Yamato" opened fire with her 460  mm main batteries. The Japanese ships stopped zigzagging and increased speed to , began taking evasive maneuvers, and opened fire with their anti-aircraft guns. "Yamato" carried almost 150 anti-aircraft guns, including her massive 460  mm main guns that fired San Shiki anti-aircraft shells. The U.S. pilots deduced that the use of San Shiki and colored gunfire meant that "Yamato's" gunners relied on visual aiming and range, rather than being radar directed, and as a result "were missing with great consistency" despite the storm of fire that they put up.


title: Operation Ten-Go

text: The American F6F Hellcat and F4U Corsair fighters "were supposed to go first, to strafe, to rocket, to drop light ordnance, distracting the enemy gunners while the SB2C Helldivers plunged almost straight down with their heavy [armor piercing] bombs". This was because the TBM Avenger torpedo bombers "needed all the distraction and diversion they could get when they made their dangerous low altitude runs straight at the enemy ships." The Avengers mainly attacked from the port side so that if the torpedoes hit that side, it would increase the likelihood of the target ship capsizing.


title: Operation Ten-Go

text: At 12:46, a torpedo hit "Yahagi" directly in her engine room, killing the entire engineering room crew and bringing her to a complete stop. "Yahagi" was hit by at least six more torpedoes and 12 bombs by succeeding waves of air attacks. The Japanese destroyer "Isokaze" attempted to come to "Yahagi"s aid but was attacked and heavily damaged and sank sometime later. "Yahagi" capsized and sank at 14:05.


title: Operation Ten-Go

text: During the first attack wave, despite evasive maneuvers that caused most of the bombs and torpedoes aimed at her to miss, "Yamato" was hit by two armor-piercing bombs and one torpedo. Her speed was not affected, but one of the bombs started a fire aft of the superstructure that was not extinguished. Also, during the first attack wave, Japanese destroyers "Hamakaze" and "Suzutsuki" were heavily damaged and taken out of the battle. "Hamakaze" sank later.


title: Operation Ten-Go

text: Between 13:20 and 14:15, the second and third waves of U.S. aircraft attacked, concentrating on "Yamato". During this time, "Yamato" was hit by at least eight torpedoes and up to 15 bombs. The bombs did extensive damage to the topside of the ship, including knocking out power to the gun directors and forcing the anti-aircraft guns to be individually and manually aimed and fired, greatly reducing their effectiveness. The torpedo hits—almost all on the port side—caused "Yamato" to list enough that capsizing was now an imminent danger.


title: Operation Ten-Go

text: At 13:33, in a desperate attempt to keep the ship from capsizing, "Yamato"s damage control team counter-flooded both starboard engine and boiler rooms. This mitigated the danger but also drowned the several hundred crew members crewing those stations, who were given no notice that their compartments were about to fill with water. The loss of the starboard engines, plus the weight of the water, caused "Yamato" to slow to about . At that same moment, the Americans launched another 110 aircraft from Task Group 58. Twenty Avengers made a new torpedo run from 60 degrees to port. Yamato started a sharp turn to port, but three torpedoes ripped into her port side amidships, jamming her auxiliary rudder in position hard port.


title: Operation Ten-Go

text: With "Yamato" proceeding more slowly and therefore being more accessible to target, U.S. torpedo aircraft concentrated on hitting her rudder and stern with torpedoes to affect her steering ability, which they succeeded in doing. At 14:02, after being informed that the ship could no longer steer and was sinking, Admiral Itō ordered the mission canceled, the crew to abandon the ship and the remaining ships to begin rescuing survivors. "Yamato" communicated this message to the other surviving ships by signal flag because her radios had been destroyed.


title: Operation Ten-Go

text: Aruga and Admiral Itō refused to abandon ship, with Itō retiring to the flag cabin while Aruga tied himself to the binnacle. As the order to abandon the ship was issued after the ship began to capsize, many of her crew were trapped. American aircraft continued to attack "Yamato" during this period, and she suffered several more torpedo hits. At 14:20, "Yamato" capsized completely and began to sink (). At 14:23, she suddenly blew up with an explosion so large that it was reportedly heard and seen away in Kagoshima and sent up a mushroom-shaped cloud almost into the air. Japanese survivor Mitsuru Yoshida said that her large explosion downed several U.S. planes observing her end. The explosion is believed to have occurred when the fires ignited by bomb hits reached the main magazines.


title: Operation Ten-Go

text: Attempting to make it back to port, Japanese destroyer was bombed and sunk with no survivors by U.S. aircraft. The Japanese destroyer was also crippled by a U.S. carrier aircraft attack during the battle and had to be scuttled by other, relatively undamaged Japanese destroyers. "Suzutsuki" was able to make it to Sasebo, Japan, despite her bow being blown off by steaming in reverse the entire way.


title: Operation Ten-Go

text: The remaining three less-damaged Japanese destroyers ("Fuyutsuki", "Yukikaze", and "Hatsushimo") were able to rescue 280 survivors from "Yamato" (sources differ on the size of "Yamato"s crew, giving it as between 2,750 and 3,300 men), plus 555 survivors from "Yahagi" (out of a crew of 1,000) and just over 800 survivors from "Isokaze", "Hamakaze", and "Kasumi". Between 3,700 and 4,250 Japanese naval personnel perished in the battle. The ships took the survivors to Sasebo.


title: Operation Ten-Go

text: A total of 10 U.S. aircraft were shot down by anti-aircraft fire from the Japanese ships; some aircrews were rescued by seaplane or submarine. In total, the U.S. lost 12 men. Some of the Japanese survivors reported that U.S. fighter aircraft strafed Japanese survivors floating in the water. Japanese survivors also reported that U.S. aircraft temporarily halted their attacks on the Japanese destroyers during the time that the destroyers were busy picking up survivors from the water.


title: Operation Ten-Go

text: During the battle, as promised, the Japanese Army conducted an air attack on the U.S. naval fleet at Okinawa, but they failed to sink any ships. Around 115 aircraft—many of them "kamikaze"—attacked the U.S. ships throughout April 7. "Kamikaze" aircraft hit the aircraft carrier , battleship , and destroyer , causing moderate damage to "Hancock" and "Maryland" and severe damage to "Bennett". About 100 Japanese aircraft were lost in the attack.


title: Operation Ten-Go

text: "Ten-Go" was the last major Japanese naval operation of the war, and the remaining Japanese warships had little involvement in combat operations for the rest of the conflict. "Suzutsuki" was never repaired. "Fuyutsuki" was repaired but hit a U.S. air-dropped mine at Moji, Japan, on 20 August 1945, and was not subsequently repaired. "Yukikaze" survived the war almost undamaged. "Hatsushimo" hit a U.S. air-dropped mine on 30 July 1945, near Maizuru, Japan, and was the 129th, and last, Japanese destroyer sunk in the war.


title: Operation Ten-Go

text: "Maryland" was kept out of the war following the "kamikaze" attacks. Okinawa was declared secure by Allied forces on 21 June 1945, after an intense and costly battle. Japan surrendered 15 August 1945, after being bombed twice with atomic weapons. The apparent willingness of Japan to sacrifice so many of its people using suicidal tactics such as Operation Ten-Go and in the Battle of Okinawa was reportedly a factor in the American decision to employ atomic weapons against Japan.


title: Operation Ten-Go

text: "Yamato" remains fairly prominent in modern Japanese culture, where she is often portrayed as a symbol of Japanese nationalism. The academic Robert Farley has written that popular depictions of the battleship portray her destruction as a "heroic, but also pointless and futile, sacrifice". One of the reasons the event may have such significance in Japanese culture is that the word "Yamato" was often used as a poetic name for Japan. Thus, the end of the battleship "Yamato" could serve as a metaphor for the end of the Japanese empire.


title: Glenn Morshower

text: Glenn Morshower is an American character actor. He is best known for playing Secret Service Agent Aaron Pierce in "24" and Colonel (later General) Sharp Morshower in the "Transformers" film series. He has also appeared in many feature films and television series.


title: Glenn Morshower

text: Morshower was raised Jewish, studied with a Jehovah's Witness, went to a Religious Science church, and taught at a Baptist church.


title: Heat engine

text: In thermodynamics and engineering, a heat engine is a system that converts heat to mechanical energy, which can then be used to do mechanical work. It does this by bringing a working substance from a higher state temperature to a lower state temperature. A heat source generates thermal energy that brings the working substance to the higher temperature state. The working substance generates work in the working body of the engine while transferring heat to the colder sink until it reaches a lower temperature state. During this process some of the thermal energy is converted into work by exploiting the properties of the working substance. The working substance can be any system with a non-zero heat capacity, but it usually is a gas or liquid. During this process, some heat is normally lost to the surroundings and is not converted to work. Also, some energy is unusable because of friction and drag.


title: Heat engine

text: In general, an engine is any machine that converts energy to mechanical work. Heat engines distinguish themselves from other types of engines by the fact that their efficiency is fundamentally limited by Carnot's theorem. Although this efficiency limitation can be a drawback, an advantage of heat engines is that most forms of energy can be easily converted to heat by processes like exothermic reactions (such as combustion), nuclear fission, absorption of light or energetic particles, friction, dissipation and resistance. Since the heat source that supplies thermal energy to the engine can thus be powered by virtually any kind of energy, heat engines cover a wide range of applications.


title: Heat engine

text: Heat engines are often confused with the cycles they attempt to implement. Typically, the term "engine" is used for a physical device and "cycle" for the models.


title: Heat engine

text: In thermodynamics, heat engines are often modeled using a standard engineering model such as the Otto cycle. The theoretical model can be refined and augmented with actual data from an operating engine, using tools such as an indicator diagram. Since very few actual implementations of heat engines exactly match their underlying thermodynamic cycles, one could say that a thermodynamic cycle is an ideal case of a mechanical engine. In any case, fully understanding an engine and its efficiency requires a good understanding of the (possibly simplified or idealised) theoretical model, the practical nuances of an actual mechanical engine and the discrepancies between the two.


title: Heat engine

text: In general terms, the larger the difference in temperature between the hot source and the cold sink, the larger is the potential thermal efficiency of the cycle. On Earth, the cold side of any heat engine is limited to being close to the ambient temperature of the environment, or not much lower than 300 kelvin, so most efforts to improve the thermodynamic efficiencies of various heat engines focus on increasing the temperature of the source, within material limits. The maximum theoretical efficiency of a heat engine (which no engine ever attains) is equal to the temperature difference between the hot and cold ends divided by the temperature at the hot end, each expressed in absolute temperature.


title: Heat engine

text: The efficiency of these processes is roughly proportional to the temperature drop across them. Significant energy may be consumed by auxiliary equipment, such as pumps, which effectively reduces efficiency.


title: Heat engine

text: It is important to note that although some cycles have a typical combustion location (internal or external), they often can be implemented with the other. For example, John Ericsson developed an external heated engine running on a cycle very much like the earlier Diesel cycle. In addition, externally heated engines can often be implemented in open or closed cycles. In a closed cycle the working fluid is retained within the engine at the completion of the cycle whereas is an open cycle the working fluid is either exchanged with the environment together with the products of combustion in the case of the internal combustion engine or simply vented to the environment in the case of external combustion engines like steam engines and turbines.


title: Heat engine

text: Everyday examples of heat engines include the thermal power station, internal combustion engine, firearms , refrigerators and heat pumps. Power stations are examples of heat engines run in a forward direction in which heat flows from a hot reservoir and flows into a cool reservoir to produce work as the desired product. Refrigerators, air conditioners and heat pumps are examples of heat engines that are run in reverse, i.e. they use work to take heat energy at a low temperature and raise its temperature in a more efficient way than the simple conversion of work into heat (either through friction or electrical resistance). Refrigerators remove heat from within a thermally sealed chamber at low temperature and vent waste heat at a higher temperature to the environment and heat pumps take heat from the low temperature environment and 'vent' it into a thermally sealed chamber (a house) at higher temperature.


title: Heat engine

text: In general heat engines exploit the thermal properties associated with the expansion and compression of gases according to the gas laws or the properties associated with phase changes between gas and liquid states.


title: Heat engine

text: Earth's atmosphere and hydrosphere—Earth's heat engine—are coupled processes that constantly even out solar heating imbalances through evaporation of surface water, convection, rainfall, winds and ocean circulation, when distributing heat around the globe.


title: Heat engine

text: A Hadley cell is an example of a heat engine. It involves the rising of warm and moist air in the earth's equatorial region and the descent of colder air in the subtropics creating a thermally driven direct circulation, with consequent net production of kinetic energy.


title: Heat engine

text: In these cycles and engines, the working fluids are gases and liquids. The engine converts the working fluid from a gas to a liquid, from liquid to gas, or both, generating work from the fluid expansion or compression.


title: Heat engine

text: A domestic refrigerator is an example of a heat pump: a heat engine in reverse. Work is used to create a heat differential. Many cycles can run in reverse to move heat from the cold side to the hot side, making the cold side cooler and the hot side hotter. Internal combustion engine versions of these cycles are, by their nature, not reversible.


title: Heat engine

text: The Barton evaporation engine is a heat engine based on a cycle producing power and cooled moist air from the evaporation of water into hot dry air.


title: Heat engine

text: Mesoscopic heat engines are nanoscale devices that may serve the goal of processing heat fluxes and perform useful work at small scales. Potential applications include e.g. electric cooling devices. In such mesoscopic heat engines, work per cycle of operation fluctuates due to thermal noise. There is exact equality that relates average of exponents of work performed by any heat engine and the heat transfer from the hotter heat bath. This relation transforms the Carnot's inequality into exact equality. This relation is also a Carnot cycle equality


title: Heat engine

text: The efficiency of a heat engine relates how much useful work is output for a given amount of heat energy input.


title: Heat engine

text: In other words, a heat engine absorbs heat energy from the high temperature heat source, converting part of it to useful work and giving off the rest as waste heat to the cold temperature heat sink.


title: Heat engine

text: In general, the efficiency of a given heat transfer process is defined by the ratio of "what is taken out" to "what is put in". (For a refrigerator or heat pump, which can be considered as a heat engine run in reverse, this is the coefficient of performance and it is ≥ 1.) In the case of an engine, one desires to extract work and has to put in heat formula_6, for instance from combustion of a fuel, so the engine efficiency is reasonably defined as


title: Heat engine

text: The efficiency is less than 100% because of the waste heat formula_8 unavoidably lost to the cold sink (and corresponding compression work put in) during the required recompression at the cold temperature before the power stroke of the engine can occur again.


title: Heat engine

text: The "theoretical" maximum efficiency of any heat engine depends only on the temperatures it operates between. This efficiency is usually derived using an ideal imaginary heat engine such as the Carnot heat engine, although other engines using different cycles can also attain maximum efficiency. Mathematically, after a full cycle, the overall change of entropy is zero:


title: Heat engine

text: Note that formula_10 is positive because isothermal expansion in the power stroke increases the multiplicity of the working fluid while formula_11 is negative since recompression decreases the multiplicity. If the engine is ideal and runs reversibly, formula_12 and formula_13, and thus


title: Heat engine

text: where formula_17 is the absolute temperature of the hot source and formula_18 that of the cold sink, usually measured in kelvins.


title: Heat engine

text: The reasoning behind this being the maximal efficiency goes as follows. It is first assumed that if a more efficient heat engine than a Carnot engine is possible, then it could be driven in reverse as a heat pump. Mathematical analysis can be used to show that this assumed combination would result in a net decrease in entropy. Since, by the second law of thermodynamics, this is statistically improbable to the point of exclusion, the Carnot efficiency is a theoretical upper bound on the reliable efficiency of "any" thermodynamic cycle.


title: Heat engine

text: Empirically, no heat engine has ever been shown to run at a greater efficiency than a Carnot cycle heat engine.


title: Heat engine

text: Figure 2 and Figure 3 show variations on Carnot cycle efficiency with temperature. Figure 2 indicates how efficiency changes with an increase in the heat addition temperature for a constant compressor inlet temperature. Figure 3 indicates how the efficiency changes with an increase in the heat rejection temperature for a constant turbine inlet temperature.


title: Heat engine

text: By its nature, any maximally efficient Carnot cycle must operate at an infinitesimal temperature gradient; this is because any transfer of heat between two bodies of differing temperatures is irreversible, therefore the Carnot efficiency expression applies only to the infinitesimal limit. The major problem is that the objective of most heat-engines is to output power, and infinitesimal power is seldom desired.


title: Heat engine

text: A different measure of ideal heat-engine efficiency is given by considerations of endoreversible thermodynamics, where the system is broken into reversible subsystems, but with non reversible interactions between them. A classical example is the Curzon–Ahlborn engine, very similar to a Carnot engine, but where the thermal reservoirs at temperature formula_17 and formula_18 are allowed to be different from the temperatures of the substance going through the reversible Carnot cycle: formula_21 and formula_22. The heat transfers between the reservoirs and the substance are considered as conductive (and irreversible) in the form formula_23. In this case, a tradeoff has to be made between power output and efficiency. If the engine is operated very slowly, the heat flux is low, formula_24 and the classical Carnot result is found


title: Heat engine

text: but at the price of a vanishing power output. If instead one choses to operate the engine at its maximum output power, the efficiency becomes


title: Heat engine

text: This model does a better job of predicting how well real-world heat-engines can do (Callen 1985, see also endoreversible thermodynamics):