There were no injuries or detectable health impacts from the accident, beyond the initial stress. This incident remains the worst accident in the history of U.S. commercial nuclear power. Decontamination may be accomplished by (1) treating the surface to remove or decrease the contamination; (2) letting the material stand so that the radioactivity is decreased by natural decay; and (3) covering the contamination to shield the radiation emitted. A clean-up plan was developed and carried out safely and successfully by a team of more than 1000 skilled workers. All are reduced, that is, improved substantially, from 1980. Usually turned by water or steam. (That run was also the longest at any steam-driven plant in the U.S., including plants powered by fossil fuels.) TheThree Mile Island accident caused concerns about the possibility of radiation-induced health effects, principally cancer,in the area surrounding the plant. This caused the plant's turbine-generator (4) and then the reactor itself to automatically shut down. The reactor vessel head (top) was removed. Pressure Vessel – A strong walled container housing the core of most types of power reactors. TMI-2 clean-up operations produced over 10.6 megalitres of accident-generated water that was processed, stored and ultimately evaporated. The accident began about 4 a.m. on Wednesday, March 28, 1979, when the plant experienced a failure in the secondary, non-nuclear section of the plant (one of two reactors on the site). Feedwater – Water supplied to the steam generator that removes heat from the fuel rods by boiling and becoming steam. Training became centred on protecting a plant's cooling capacity, whatever the triggering problem might be. Three Mile Island Accident The accident at the Three Mile Island Unit 2 (TMI-2) nuclear power plant near Middletown, Pa., on March 28, 1979, was the most serious in U.S. commercial nuclear power plant operating history, even though it led to no deaths or injuries to plant workers or members of the nearby community. Careful analysis of the accident's events identified problems and led to permanent and sweeping changes in how NRC regulates its licensees – which, in turn, has reduced the risk to public health and safety. Cladding – The thin-walled metal tube that forms the outer jacket of a nuclear fuel rod. Executive Summary An accident at the Three Mile Island-Unit with past and present Advisory Panel 2 facility (TMI-2) on March 28, 1979, participants including Panel members, involved a loss of reactor coolant and NRC staff, licensee staff, general public, resulted in serious damage to the reactor and media representatives. Disciplines in training, operations and event reporting that grew from the lessons of the TMI-2 accident have made the nuclear power industry demonstrably safer and more reliable. In 1988 a 1.3% (11 MWe) uprate was licensed. The NRC website has a factsheet on Three Mile Island. This includes fire protection, piping systems, auxiliary feedwater systems, containment building isolation, reliability of individual components (pressure relief valves and electrical circuit breakers), and the ability of plants to shut down automatically; Identifying the critical role of human performance in plant safety led to revamping operator training and staffing requirements, followed by improved instrumentation and controls for operating the plant, and establishment of fitness-for-duty programs for plant workers to guard against alcohol or drug abuse; Enhancing emergency preparedness, including requirements for plants to immediately notify NRC of significant events and an NRC Operations Center staffed 24 hours a day. Operations produced over 10.6 megalitres of accident-generated water that was processed, stored and ultimately evaporated itself. From background radiation is 300 millirem per year number of significant events from! 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