Three Mile Island 
Three Mile Island is a nuclear Power Plant located in Middletown, Pennsylvenia, five miles south of Harrisburg. On March 28, 1997 a minor malfunction occured in the system which feeds water to the steam generators. The plant was automatically shut down, and pressure and temperature in the reactor increased, causing the pressure relief valve to open. The valve got stuck and did not close as conditions returned to normal. This went unnoticed for several hours, in which time, water that cooled the core evaporated into the atmosphere and 90% of the reactor core was damaged. This was the most serious, and most publicized, commercial nuclear accident in US history.
The cause of the accident was officialy reported as operational errors and the result of an inadequate plant design. The health effects of the incident are generally believed to be very small. Almost all of the gasses released are reported to be harmless and the radiation is said to be harmless. The psychological effect the incident had on the public was, however, severe. Despite these findings, a study done by Dr. Earnest J. Sternglass, profesor of radiation physics at the University of Pittsburg) showed that the accident led to a minimum of 430 infant deaths.
The general conception is that this accident set an example for the nuclear industry. It is said that becasue of the accident at Three Mile Island, US power plants are now operated more safely than ever.

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