March 28th marks the 36th anniversary of the partial meltdown of one of the reactors at the Three Mile Island nuclear plant in Pennsylvania.

Here are three things you may not have known about the Three Mile Island accident:

One: Property damage and cleanup cost nearly $3.5 billion. The cleanup process took 14 years.

Two: There is another reactor at Three Mile Island that continues to run today.

Three: The accident rated as a five on International Nuclear Event Scale, which runs from zero to seven.