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Meltdown at Three Mile Island | Timeline

Timeline of Nuclear Technology

December — Dr. Enrico Fermi achieves the first controlled nuclear chain reaction, with a natural uranium device moderated with graphite. Fermi conducted the process using the first demonstration reactor, known as Chicago Pile 1.

Dr. Enrico Fermi

August — The United States, at the order of President Harry S. Truman, drops two atomic bombs on Japan. The first is dropped on Hiroshima on August 6, a second is dropped three days later on Nagasaki. Together, the two bombs kill over 130,000 people and kill thousands more from radiation poisoning over the subsequent months. Japan surrendered to the U.S. on August 14.

August — President Harry S. Truman signs The Atomic Energy Act of 1946. The act places the newly devised nuclear energy industry under civilian control. The Joint Congressional Committee on Atomic Energy is also established at this time to monitor the growth and actions of the industry.

October — The Atomic Energy Commission begins work on a report investigating peaceful uses of nuclear energy.

December — The Atoms For Peace program is unveiled by President Dwight Eisenhower. Eisenhower proposed the creation of an international agency devoted to developing peaceful nuclear technologies. Eisenhower spoke of taking nuclear materials "out of the hands of soldiers...(and placing them) into the hands of those who will...adapt (them) to the arts of peace."

August — The first major amendment to the 1946 Atomic Energy Act is made when President Eisenhower gives the civilian nuclear energy program further access to nuclear technology.

January — The Atomic Energy Commission announces a cooperative program between the federal governement and the nuclear power industry to develop power plants. 

July — Arco, Idaho, with a population of 1,000, is the first U.S. town powered by nuclear energy. The town's energy was supplied by an experimental boiling-water reactor called the Borax III. 

November — An experimental breeder reactor about 50 miles west of Idaho Falls, Idaho, partially melts down during a test. The cause of the partial meltdown was attributed to operator error.

July — The Sodium Reactor Experiment at Santa Susana, California becomes the first civilian nuclear power unit to go on-line. The unit continued to generate power until 1966. 

September — President Eisenhower signs the Price-Anderson Act, which will protect private citizens, public utilities, and contractors from incurring financial hardship in the event of an accident at a nuclear power plant. 

October — The Windscale plutonium production reactor catches fire spreading approximately 20,000 curies of radioactive iodine across Great Britain and northern Europe. 

December — Shippingport, Pennsylvania is the site of the first full-scale nuclear power plant in the U.S. The plant was able to generate 60 megawatts of electricity after reaching full power 21 days after going on-line.

October — The first nuclear power plant in the U.S. to be built without any government funding -- the Dresden 1 Nuclear Power Station in Illinois -- achieves a self-sustaining nuclear reaction.

January — The SL-1 reactor, located at Idaho Falls, goes out of control causing a rupture of the building. The damaged core was reported to have emitted radiation at a rate of more than 500 rems per hour.

December — The Jersey Central Power and Light Company announces its plans to construct a nuclear power plant at Oyster Creek as an economic alternative to a fossil-fuel plant. The company contended that its research indicated that nuclear power would generate energy less expensively than fossil fuels.

December — The Atomic Energy Commission issues Jersey Central Power and Light Company a construction permit to begin building the Oyster Creek nuclear power plant.

November -- A major electrical power outage in the northeastern U.S. prompts proponents of nuclear power to push it as a necessary alternative energy source.

October — The Enrico Fermi experimental breeder near Detroit, Michigan is the site of what is considered an "uncomfortably close call," as its core partially melts. Although a runaway reaction was prevented, the reactor was permanently disabled.

October — The Organization of Petroleum Exporting Countries (OPEC) votes to cut oil exports by five percent until Israel agrees to withdraw from all Arab territories it occupied during the Yom Kippur War. Failing to achieve that result, Saudi Arabia decided days later to cut oil production by 25 percent and joined with other oil-producing nations in an embargo of oil shipments to the United States. An "Energy Crisis" gripped the U.S. resulting in price gouging, gas lines and rationing.

October -- President Gerald Ford abolishes The Atomic Energy Commission and replaces it with two new agencies: the Energy Research and Development Administration and the Nuclear Regulatory Commission. The two new bodies were charged with the task of regulating the nuclear industry.

April — President Jimmy Carter announces a policy banning the reprocessing of used nuclear fuel.

September — Dedication ceremonies for Three Mile Island Unit 2 are held in Harrisburg, Pennsylvania. Deputy Secretary of Energy for the Carter Administration, John F. Oน Leary called the plant a "scintillating success," and added that "it is fair to conclude...that nuclear power is a bright and shining option for this country."

March — Equipment failures and human error contribute to an accident at the Three Mile Island nuclear reactor at Harrisburg, Pennsylvania. A series of events led to the worst nuclear accident in U.S. history. 

October — Reacting to public and political outrage over events at Three Mile Island, the U.S. nuclear energy industry creates the Institute of Nuclear Power Operations to address issues of safety and performance

October — Reversing a decision made by President Carter in 1977, President Ronald Reagan's administration decides to lift the ban on reprocessing used nuclear fuel. The Reagan administration went on to introduce a policy calling for the need for a high-level radioactive waste storage facility.

January — The Nuclear Waste Policy Act is signed into law by President Ronald Reagan. The act established a timetable for designating permanent underground facilities for the storage of nuclear waste. 

April — The Atomic Industrial Forum, a pro-nuclear power group, publishes a statement that the 1979 accident at Three Mile Island did not fundamentally change its otherwise unblemished safety record. In its bulletin, the AIF contended that, "No member of the public has been injured or killed from a reactor accident at a commercial nuclear power plant. ...No plant employee ever has exhibited clinical evidence of serious injury from radiation. ...The nation's most serious commercial nuclear plant accident...did not alter this unparalleled record of safety." 

October — Congress votes to kill funding for the Clinch River Breeder Reactor project in Tennessee.

May -- A report made by Oak Ridge Associated Universities and the University of North Carolina links incidents of cancer in workers at the Savannah River nuclear power plant, located near Aiken, South Carolina to exposure to radiation.


April — Runaway reactions during a test at the Chernobyl nuclear reactor near Kiev, located in the what was then the Soviet Union, causes a series of explosions that rupture the containment structure and send massive amounts of radiation through the Northern Hemisphere. Soviet troops were dispatched to help fight the fire and contain the reactions in the melted core. The incident at Chernobyl was the worst nuclear accident in history and resulted in over 75 million people being exposed to dangerously high levels of radiation. 

August — Soviet medical experts predict an increase of nearly 30,000 cancer-related deaths over a 50 year period due to fall-out from the accident at Chernobyl.

May -- New York State, led by Governor Mario Cuomo and the Long Island Lighting Company (LILCO) reach an agreement to close and dismantle the Shoreham nuclear power plant. The $5.3 billion loss was absorbed by the utility's investors, electricity customers on Long Island, and federal taxpayers.

August — Uniform nuclear plant designs are submitted to the Nuclear Regulatory Commission for certification and approval. The designs were drawn up in the hopes of establishing a single standard for nuclear power plant construction in the U.S. 

October — President George Bush signs into law the Energy Policy Act, setting the U.S. on course for planning its energy needs. The act also reformed the licensing process for advanced, standardized nuclear power plants. The updated process was designed to afford the public more timely opportunities to participate in decisions concerning the construction of nuclear power plants. It was also drawn up to provide investors with a more stable financial environment.

April — The Comanche Peak Unit 2 nuclear power plant in Glen Rose, Texas, goes on-line. The plant went on to provide 1,150 megawatts of electricity to consumers.

January — The United States purchases uranium from the Russian Federation, planning to blend it down into power plant fuel. The U.S. made the purchase to keep the uranium from being used for missile warheads. 

July — The Nuclear Regulatory Commission issues its final design approval of the first two of four advanced nuclear power plant designs for General Electric's Advanced Boiling Water Reactor and ABB Combustion Engineering's System 80+. The two plants were the first to obtain final design approval under the NRC's regulations for licensing standardized plant designs.

February — The Tennessee Valley Authority (TVA) is granted a full-power license by the Nuclear Regulatory Commission for its Watts Bar 1 nuclear power plant. The licensing brought the number of operating nuclear units in the U.S. to 110. 

June — District Court Judge Sylvia Rambo dismisses a class action lawsuit filed against the Metropolitan Edison Company, on behalf of individuals and businesses said to have been exposed to and injured by gamma radiation exposure during the 1979 Three Mile Island accident. The judge cited a "scarcity of evidence" in dismissing the case.

January — President Bill Clinton announces that China has issued support of international nuclear proliferation efforts. The announcement paved the way for the sale of U.S. nuclear technology to China, a move protested by many members of Congress.

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