Radioactive waste management covers everything from the moment a material is no longer useful (or no longer expected to be reused) up to its final disposal. The regulatory aim is to protect people and the environment, today and in the long term, without imposing undue burdens on future generations.

Classification

The IAEA general scheme (Safety Guide GSG-1) recognises six classes by activity content and disposal pathway:

  • Exempt waste (EW) — below clearance levels; can leave regulatory control.
  • Very short-lived waste (VSLW) — can be stored for decay and then cleared (typical half-life < 100 days).
  • Very low-level waste (VLLW) — typically disposed in near-surface engineered facilities.
  • Low-level waste (LLW) — engineered near-surface disposal.
  • Intermediate-level waste (ILW) — significant radionuclide content, may need shielding; deeper-engineered disposal.
  • High-level waste (HLW) — heat-generating; vitrified reprocessing waste or spent nuclear fuel. Deep geological disposal.

National classification systems vary in cutoffs and naming. The Swedish scheme uses operational categories (driftavfall, rivningsavfall, kärnavfall, kärnämne) that map but are not identical to the IAEA scheme.

Conditioning and packaging

Conditioning means turning waste into a form suitable for handling, storage, transport and disposal. Common processes:

  • Compaction — for solid LLW: super-compactors that reduce volume by factor 4-10.
  • Cementation — solidifying sludge, resins or evaporator concentrates in cement matrix.
  • Vitrification — borosilicate glass for HLW from reprocessing (PIVER, AVM, R7/T7 in France; WVDP in US; Sellafield WVP in UK).
  • Bituminisation — for some sludges (historic; less used now).

Packages must meet the IAEA Transport Regulations (SSR-6) for any movement off-site. Disposal packages additionally must satisfy waste acceptance criteria (WAC) at the receiving facility, covering activity, fissile content, leachability, gas generation, criticality and structural integrity.

Storage versus disposal

Storage and disposal are different concepts in the IAEA framework:

  • Storage — retention of waste with intention of later retrieval. Engineered facilities with active institutional control.
  • Disposal — emplacement with no intention of retrieval. Passive safety must be demonstrated for a defined timeframe (10,000 to 100,000+ years for HLW).

Several national programmes deliberately design retrievability into early-stage disposal to give future generations decision flexibility.

Facility types

  • Near-surface engineered facility — for VLLW, LLW: El Cabril (ES), Centre de l'Aube (FR), Vaalputs (ZA), Drigg (UK).
  • Intermediate-depth or short-lived ILW facility — SFR Forsmark (SE), Olkiluoto VLJ (FI).
  • Deep geological repository (DGR) — Onkalo (FI, under construction), planned SKB Forsmark KBS-3 (SE), Bure Cigéo (FR, in licensing), planned DGRs in CH (NAGRA), CA, DE, JP, KR, US (WIPP for defense TRU only, currently no commercial-HLW DGR).

Long-term safety case

The safety case for a disposal facility is the integrated argument that the system will perform within regulatory criteria over the assessment period. It includes:

  • Site characterisation and geological framework.
  • Engineered-barrier design (containers, buffer, backfill, seals).
  • Operational safety analysis (during the operational phase, often 50-100 years).
  • Post-closure safety analysis (centuries to millions of years).
  • Uncertainty analysis: scenarios (probable evolution, climate, intrusion), parameter variability, conceptual model uncertainty.
  • Reversibility and retrievability considerations.

Polluter pays and financial assurance

International practice requires advance financial provision for waste management and decommissioning so that the present generation pays for its own disposal. National financing mechanisms include trust funds (US), state-owned waste companies (SKB-SE, Posiva-FI, ENRESA-ES, ONDRAF/NIRAS-BE), and producer levies.