- Three Mile Island
an island in the Susquehanna River, near Middletown, Pennsylvania, SE of Harrisburg: scene of a near-disastrous accident at a nuclear plant in 1979 that raised the issue of nuclear-energy safety.
* * *Nuclear power station near Harrisburg, Pa., site of the most serious accident in the history of the U.S. nuclear power industry (March 28, 1979). Mechanical failures and human errors caused a partial meltdown of the nuclear core and the release of radioactive gases. Despite assurances that there had been little risk to people's health, the accident increased public fears about the safety of nuclear power and strengthened public opposition to its use, effectively stopping construction of nuclear reactors and further development of U.S. nuclear power plants.
* * *nuclear power (nuclear energy) station and the island on which it is situated, in the Susquehanna River near Harrisburg, Pennsylvania, U.S. The most serious accident in the history of the American nuclear power industry occurred there in 1979. At 4:00 AM on March 28, an automatically operated valve in the Unit 2 reactor mistakenly closed, shutting off the water supply to the main feedwater system (the system that transfers heat from the water actually circulating in the reactor core). This caused the reactor core to shut down automatically, but a series of equipment and instrument malfunctions, human errors in operating procedures, and mistaken decisions in the ensuing hours led to a serious loss of water coolant from the reactor core. As a result, the core was partially exposed, and the zirconium cladding of its fuel reacted with the surrounding superheated steam to form a large accumulation of hydrogen gas, some of which escaped from the core into the containment vessel of the reactor building. Very little of this and other radioactive gases actually escaped into the atmosphere, and they did not constitute a threat to the health of the surrounding population. In the following days adequate coolant water circulation in the core was restored.The accident at Three Mile Island, though minuscule in its health consequences, had widespread and profound effects on the American nuclear power industry. It resulted in the immediate (though temporary) closing of seven operating reactors like those at Three Mile Island. A moratorium on the licensing of all new reactors was also temporarily imposed, and the whole process of approval for new plants by the Nuclear Regulatory Commission was significantly slowed for years after the accident. No new reactors were ordered by utility companies in the United States from 1979 through the mid-1980s. The accident increased public fears about the safety of nuclear reactors and strengthened public opposition to the construction of new plants. The unharmed Unit 1 reactor at Three Mile Island did not resume operation until 1985. The cleanup of Unit 2 continued until 1990; damage to the unit was so severe, however (52 percent of the core melted down), that it remained unusable.
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Three Mile Island — Centrale nucléaire de Three Mile Island avec ses 4 tours de réfrigération. Les réacteurs nucléaires sont contenus dans les deux dômes en béton … Wikipédia en Français
Three Mile Island — es una isla en el río Susquehanna cerca de Harrisburg, Pensilvania, del área el km² 3,29. El nombre de la isla es comúnmente asociado con un accidente de generación nuclear de la estación del mismo nombre que ocurrió el 28 de marzo de 1979 cuando … Enciclopedia Universal
Three Mile Island — [θriː maɪl aɪlənd], Kernkraftwerk bei Harrisburg (Pa.), USA. Im Druckwasserreaktor des Kraftwerkblocks TMI 2 (960 MW Leistung) ereignete sich am 28. 3. 1979 der bis dahin schwerste bekannte Unfall in einem Kernkraftwerk. Dabei wurde nach… … Universal-Lexikon
Three Mile Island — f1 Kernkraftwerk Three Mile Island Kernkraftwerk von Three Mile Island, in dem es 1979 zur Kernschmelze kam … Deutsch Wikipedia
Three Mile Island — АЭС «Три Майл Айленд». В центре два энергоблока в бетонных контейнментах (TMI 2 дальний). На заднем плане градирни Три Майл Айленд (англ. Three Mile Island трёхмильный остров) название места, в котором расположена атомная электростанция, на… … Википедия
Three Mile Island — an island in the Susquehanna River, near Middletown, Pennsylvania, SE of Harrisburg: scene of a near disastrous accident at a nuclear plant in 1979 that raised the issue of nuclear energy safety. * * * Three Mile Island [Three Mile Island] a US… … Useful english dictionary
Three Mile Island — Sp Trijų Mỹlių salà Ap Three Mile Island L Saskvehanos u., JAV (Pensilvanija) … Pasaulio vietovardžiai. Internetinė duomenų bazė
Three Mile Island — Three′ Mile Is′land n. geg an island in the Susquehanna River, SE of Harrisburg, Pennsylvania: nuclear plant accident in 1979 … From formal English to slang
Three Mile Island — Three Mile Is|land a nuclear power station in Pennsylvania in the US, where there was a serious accident in 1979. The people in charge managed to prevent a ↑meltdown (=when the nuclear material melts and burns through its containers) , but the… … Dictionary of contemporary English
Three Mile Island — island in Pennsylvania (USA), site of a nuclear meltdown in 1979 … English contemporary dictionary