The Los Alamos facility in New Mexico was one of those detailed
A document providing confidential details of US civilian nuclear sites was accidentally posted on the internet, the government has admitted.
The 266-page document included the precise location of stockpiles of fuel for nuclear weapons, the Obama administration said.
The Government Printing Office website took down the posting on Tuesday after experts expressed concern.
US officials insisted the information detailed was not a security threat.
The document, which lists itself as "sensitive but unclassified", contains maps and information on hundreds of US civilian nuclear sites.
No military installations are included but the document does cover the nuclear weapons laboratories at Los Alamos, Livermore and Sandia.
An internet site of the Federation of American Scientists in Washington had highlighted the document's existence on Sunday, saying it was "a one-stop shop for information on US nuclear programs".
A spokesman for the printing office told the New York Times the document had been gathered "under normal operating procedures" and was removed on Tuesday pending a review.
US analysts said although much of the information was already available to the public, the disclosure, particularly of the location of the fuel stockpiles, was embarrassing for the government.
The Times said the document was collated as part of a US drive to make its civilian nuclear programme more transparent in the hope that other nations, particularly Iran, would follow suit.
It said the most serious disclosure was on the Oak Ridge National Laboratory in Tennessee, known as the Fort Knox of highly enriched uranium, the leading fuel for nuclear weapons.
Damien LaVera, a spokesman for the National Nuclear Security Administration, confirmed the material should not have been released.
But he said: "The departments of energy, defence and commerce and the [Nuclear Regulatory Commission] all thoroughly reviewed it to ensure that no information of direct national security significance would be compromised."