The rock-melting-capsule concept utilizes decay heat from high-level radioactive wastes in a container to melt rock. Descent by gravity achieves deep disposal. Molten rock resolidifies in the wake of the capsule, providing permanent isolation from the environment. Results calculated for:

  1. waste categories of fission products, actinides, and Sr + Cs
  2. spherical capsule radii of 25, 50, and 100 cm
  3. waste oxide volume fractions of 0.15, 0.30, and 0.50
  4. basalt and granite rock types
indicate adequate heat generation for rock melting, maximum depth increases with capsule size and waste concentration, with depths greater than 10 km obtainable by each waste category. Further work is recommended to investigate corrosion and erosion of refractory container materials in contact with waste oxide melts and molten rock.