The 266-page document was published on May 6 as a transmission from President Barack Obama to the U.S. Congress. According to the document, the list was required by law and will be provided to the International Atomic Energy Agency.
Some of the pages are marked "highly confidential safeguards sensitive."
While there is security at the facilities, the list could presumably be useful for terrorists or anyone else who would like to harm the United States.
The publication of the list was first reported in an online secrecy newsletter Monday.
The document details the location of the nuclear sites and what is being done there.
For instance, there are nuclear reactors at the Westinghouse Electric Company in Pittsburgh, Pa. This facility is currently working on research into what happens when there are accidents with the nuclear reactors. The project started in 2006 and is expected to end in 2012, according to the document.
The document was posted on the Government Printing Office Web site, and has since been removed.