Enterprise was overbuilt for her design. She was the first thus kind of a “demo”. She had EIGHT nuclear reactors... EIGHT. They essentially have to slice into the ship in order to defuel and remove them. This all needs be done before a scrapping yard will even touch her.
They used smaller submarine reactors instead of the larger ones they developed for later surface ships. (The earlier N.S. Savannah used a completely different commercial design and the reactor, defueled, is still on the ship.)