Construction of the Unit 1 reactor began on Three Mile Island in May 1968, with the production of commercial electricity beginning in 1974. Approval for the construction of the Unit 2 reactor was granted in November 1969, and it was only producing commercial electricity for less than 90 days when on March 28, 1979, a loud roar erupted from the nuclear power plant that shook windows and awakened residents in the communities on both sides of the Susquehanna River. This loud warning was the result ...