Typical raw wastes from a 1,300 MWe nuclear power plant are combustible and compactable waste. The raw waste is pre-sorted into combustible and non-combustible substances. The non-combustible but compactable waste is compacted. The volume reduction factor is about 2 to 5. The combustible waste is burnt. The ash volumes amount to as little as 1/50 of the raw waste volumes. The ash volumes may be reduced further by the factor of two using a high-pressure press.