The depleted uranium waste from nuclear reactors can be with us for thousands years. Yucca Mountain was going to be the US repository for spent nuclear reactor fuel and other radioactive waste, but as of 2009 that project has been killed.
From the United States Department of Energy
Some next generation nuclear reactor technologies, such as the Traveling-Wave Reactor, or the Fast-Neutron Reactor might be able to solve two problems. One, consume our stockpiles of depleted uranium waste, and second use this waste to generate clean power.
I am not an expert in these technologies, but I am putting together this page with videos and links to more information for those who might be interested in this subject. These are not the only solutions that are currently available there several others (e.g. Thorium reactors), but these are ones that I am following.
"A traveling-wave reactor, or TWR, is a kind of nuclear reactor that can convert fertile material into fissile fuel as it runs using the process of nuclear transmutation. TWRs differ from other kinds of fast-neutron and breeder reactors in their ability to, once started, reach a state whereafter they can achieve very high fuel utilization while using no enriched uranium and no reprocessing, instead burning fuel made from depleted uranium, natural uranium, thorium, spent fuel removed from light water reactors, or some combination of these materials. The name refers to the design characteristic that fission does not happen in the entire TWR core, but takes place in a fairly localized zone that advances through the core over time." - Wikipedia
At TED2010, Bill Gates unveils his vision for the world's energy future, describing the need for "miracles" to avoid planetary catastrophe and explaining why he's backing a dramatically different type of nuclear reactor. The necessary goal? Zero carbon emissions globally by 2050.
A fast neutron reactor or simply a fast reactor is a category of nuclear reactor in which the fission chain reaction is sustained by fast neutrons. Such a reactor needs no neutron moderator, but must use fuel that is relatively rich in fissile material when compared to that required for a thermal reactor. - Wikipedia
Barry Brook, Director of Climate Science at The University of Adelaide Environment Institute, discusses the potential impact of fast nuclear reactors. He explains that by recycling and reusing nuclear waste, these plants are capable of turning a golf ball-sized piece of uranium into a lifetime's worth of energy. "The U.S. has mined enough uranium already, to power all of its energy needs for about a thousand years," explains Brook.
Small Nuclear Fission Reactors
Taylor Wilson was 14 when he built a nuclear fusion reactor in his parents' garage. Now 19, he returns to the TED stage to present a new take on an old topic: fission. Wilson, who has won backing to create a company to realize his vision, explains why he's so excited about his innovative design for small modular fission reactors -- and why it could be the next big step in solving the global energy crisis.