The USS Independence was one of the important aircraft carriers in the US fleet during the World War II and was actively involved in the Pacific campaign against the Japanese at the end of the war. Shortly after the war, the Cold War started between the United States and the Soviet Union and both of them had tested nuclear bombs and were swiftly moving towards ballistic missiles and space programs. Now that the USA wasn’t worried about its Western Coast, it wanted to use it to undertake some military experiments that have always remained shrouded in secrecy.
One of these was a very dangerous experiment called Operation Crossroads in which more than 90 big and small vessels of the US Navy were attached to the operation. In this project, several nuclear blast were exploded within a 1700 feet radius around the ships to test their endurance in an actual war-like situation. Now the military knew what was going to happen but they needed to know in a practical demonstration so they commissioned this operation and watched as a whole fleet of ships was sank and they recorded all the data they needed to know. More than 14 ships were sunk and the rest of them were damaged beyond recognition and were left unfit for further operations. Two blasts caused this much destruction and the third one planned was eventually scrapped.
Now the Independence was one of those ships that were severely damaged and were later taken back to the San Francisco docks for further experiments. James Delgado, a maritime archeologist who recently studied about the ship in detail has concluded that it was about a level that you get with an average X-ray. But, its close exposure to radiation meant that it was dangerous to keep such a ship around for a long time and since it was obsolete anyway, it was eventually sunk by the Navy right in the middle of the Pacific and now resides at the bottom of the deepest ocean in the world. It also had drums full of nuclear waste as well so good riddance I guess.
The mission was largely classified till last year when the Naval Radiological Defense Laboratory confirmed last year and provided access to civilians on it. The reason was because of the Fukushima disaster and how its radiation leaked into the ocean. Now the sunken aircraft carrier is also being monitored for potential leaks. It does seem pretty stupid to sink it an ocean from where it could get anywhere else!