[en] There are 103 commercial nuclear power stations currently operating in the United States, generating a total of about 2000 t of spent fuel each year. Over 40000 t of spent fuel have accumulated since these plants began operation, with the fuel being stored first in at-reactor spent fuel storage pools and later in independent spent fuel storage installations and dry cask storage facilities. The Congress of the United States recently authorised the construction of a deep geologic repository for the storage of high-level radioactive waste at the Yucca Mountain site in the state of Nevada. The total cost of this repository, including construction, waste emplacement and closure, is approximately USD 58 billion. The Nuclear Waste Policy Act as amended in 1987 limits the Yucca Mountain repository to the storage of 63 000 t of spent nuclear fuel and 7000 t of other high-level wastes, although the practical capacity of the site is estimated to be about 120 000 t of spent fuel. At the current rate of spent fuel generation, the U.S. inventory of spent fuel will reach the 63 000 t level at about the same time that the repository is prepared to begin receiving spent fuel. Accordingly, it is necessary to take actions that will limit the rate of accumulation of spent fuel while permitting the expansion of nuclear power, a course of action that may be an essential element of a national strategy for energy supply in the 21 century. The alternative is to being the search for a second repository site in the very near future; this option faces significant political obstacles. (author)