Sources, types and classification of wastes

15.1.1 Waste sources and categories

The various types of RAW are classified according to the half-lives and radioactivity levels of the main radionuclides they contain, to their physical and chemical characteristics, as well as to their origins. Half-lives are divided into very-short (less than 100 days), short (between 100 days and 31 years) and long (over 31 years).

In France, there are six major waste categories depending on their radio­active content (activity level and half-life), as follows:

• High-level waste (HLW) consists mainly of vitrified-waste packages in the form of stainless-steel containers, which contain the vast majority of radionuclides, whether in the form of fission products or of minor acti­nides. Radionuclides contained in spent fuel are separated from pluto­nium and uranium during fuel reprocessing at the La Hague plant. The activity level of vitrified waste is on the order of several billions of Bec — querels per gram.

• Long-lived intermediate-level waste (LL-ILW) originates mostly from the reprocessing of spent fuel and consists of structural residues from nuclear fuel (i. e., hulls (sheath sections) and ends, which were condi­tioned initially into cemented waste packages, but are now compacted into stainless-steel containers). It also includes technological waste (e. g., used tools, equipment, etc.) and residues resulting from the processing of effluents, such as bituminized sludge. The activity of these residues ranges between 1 million and 1 billion Becquerels per gram. There is either no or a negligible heat release.

• Long-lived low-level waste (LL-LLW) consists mainly of graphite and radium-bearing waste. The activity of graphite waste lies between 10,000 and 100,000 Becquerels per gram. Its long-term activity arises from long-lived beta-emitting radionuclides. Radium-bearing waste contains long-lived alpha-emitting radionuclides and their activity lies between a few tens to a few thousands of Becquerels per gram.

• Short-lived low — and intermediate-level waste (SL-LILW) results mainly from the operation and dismantling of nuclear power plants (NPP), fuel cycle facilities and research establishments, as well as, for a small amount, from activities relating to biological and academic studies. Most residues in this category were disposed of in a surface facility at the Centre de la Manche disposal facility (CSM) up until 1994 and at Centre de l’Aube disposal facility for LILW (CSFMA) since 1992.

• Very-low-level waste (VLLW) is mostly from the operation, mainte­nance and dismantling of NPPs, fuel cycle facilities and research estab­lishments. Its activity level is generally lower than 100 Becquerels per gram. All residues of this category are disposed of at the Centre de l’Aube disposal facility for VLLW (CSTFA).

• Very-short-lived waste includes residues that result notably from medical uses.

For practical purposes, the acronyms listed in Table 15.1 are often used.

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