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CH3041
NUCLEAR WASTES II
• After 1000 years the radioactivity is from heavy elements such as 239Pu (t½ 24 000y).
• The lighter nuclides in solution are stored in stainless steel & concrete containers as
medium-level waste for long periods (>5y).
• The heavy nuclides are extracted to form high-level waste which must be stored.
• Synroc (CSIRO), a synthetic heat & leach resistant  black rock (hollandite, zirconolite, perovskite), incorporates the radioactive elements in high-level waste for burial.
• Permanent commercial burial sites are being looked at in W.A. and S.A.
• US uses sites at the WIPP repository in New Mexico in stable salt formations.
Waste Isolation Pilot Plant