 There is an "international consensus on the advisability of storing nuclear waste in deep underground repositories", but no country in the world has yet opened such a site.The Obama administration has disallowed reprocessing of nuclear waste, citing nuclear proliferation concerns.Horizontal drillhole disposal describes proposals to drill over one kilometer vertically, and two kilometers horizontally in the earth’s crust, for the purpose of disposing of high-level waste forms such as spent nuclear fuel, Caesium-137, or Strontium-90.