Three Mile Island, Pennsylvania

Releases of radioactive materials from nuclear power plants have occurred, as at Three-Mile Island, Pennsylvania. In such situations, releases may be sufficient to require evacuation of residents. 

Two accidents of vastly differing severity have occurred at nuclear power plants. On 28 March 1979, an accident occurred in the nuclear power plant at Three Mile Island, Pennsylvania, USA. The radiation was contained and the small amount released had negligible effects on the health of individuals at the plant. On 26 April 1986 an accident occurred in the nuclear power plant 10 miles from the city of Chernobyl, then part of the Soviet Union. The chain reaction in the radioactive core of one of the four reactors became uncontrolled. Steam pressure rose to dangerous levels there were several explosions and a subsequent fire took several hours to extinguish. Large amounts of radioactive material were scattered over a wide area and into the atmosphere (later descending in a dilute form in rain all over the world). 

The world use of nuclear power to supply a nation s electricity varies widely by country. France, for example, gets around 75% of its electricity from nuclear power, and several other European countries get over half of their energy from this source. Approximately 20% of the electricity in the United States comes from 103 operating nuclear power plants. Nuclear is second only to coal, 50%, and ahead of natural gas, 15%, hydropower, 8%, and oil, 3%, as a source of electrical energy. Although once hailed by President Eisenhower in the 1950s as a safe, clean, and economical source of power, the US. nuclear industry has fallen on hard times in the last twenty-five years. Nuclear accidents at Three Mile Island, Pennsylvania,... 

Several accidents in nuclear facilities have been extensively analyzed and reported. The three most widely publicized accidents were at Windscale (now known as Sellafield), United Kingdom, in 1957 Three Mile Island, Pennsylvania, in 1979 and Chernobyl, Ukraine, in 1986 (UNSCEAR 1988 Severn and Bar 1991 Eisler 1995). From the accident at Windscale about 750 trillion (T)Bq 22 TBq Cs, 3 TBq Sr, and 0.33 TBq °Sr were released and twice the amount of noble gases that were released at Chernobyl, but 2000 times less and Cs. From the Three Mile Island accident, about 2% as much noble gases and 50,000 times less than from the Chernobyl accident were released. The most abundant released radionuclides at Three Mile Island were Xe, Xe, and but the collective dose equivalent to the population during the first post-accident days was <1% of the dose accumulated from natural background radiation in a year. 

Los Alfaques Three Mile Island, Pennsylvania Propylene transfer Nuclear reactor accident 216 200... 

Even if terrorists succeeded in detonating an explosive at a reactor site, the health consequences would be limited. The reactor accident at the Three Mile Island, Pennsylvania nuclear power plant caused a small release of radiation, insufficient to cause any radiation injuries. Bypassing several safety systems caused the Chernobyl reactor incident, involving two explosions, fires and reactor core meltdown. This accident caused the following early phase health effects (1) ... 

Nuclear power plant accidents at Three Mile Island, Pennsylvania, and Chernobyl, Ukraine, focus world attention on the dangers associated with nuclear power. 

The potential dangers of nuclear power were tragically demonstrated by the accidents at Three Mile Island, Pennsylvania (1979), and Chernobyl in the former U.S.S.R. (1986). Both accidents resulted from the loss of coolant to the reactor core. The reactors at Three Mile Island were covered by concrete containment buildings and therefore released a relatively small amount of radioactive material into the atmosphere. But because the Soviet Union did not require containment structures on nuclear power plants, the Chernobyl accident resulted in 31 deaths and the resettlement of 135,000 people. The release of large quantities of 1-131, Cs-134, and Cs-137 appears to be causing long-term health problems in that exposed population. 

Nuclear accidents at Three Mile Island, Pennsylvania, in 1979 and Chernobyl, Ukraine, in 1986 had a devastating effect on public opinion in the United States and, to a smaller degree, elsewhere in the world. At Three Mile Island only about 50 curies of radiation were released to the environment and there were no casualties. The explosion at Chernobyl was a very different story. About 100 million curies were released, leading to at least 31 fatalities. Moreover, 135,000 people were permanently evacuated from the region surrounding the reactor. Since then, all the other reactors at Chernobyl—three, in addition to the one that exploded—have been permanently shut down. 

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