Management of Radioactive Waste. Jean-Claude Amiard
Читать онлайн книгу.1.3.3.3. Hospital radioactive waste
With respect to hospital radioactive effluents, French legislation is very strict and requires the intervention of official institutions, in particular ANDRA, for the conditioning, elimination, transport and storage of this waste [FRE 01, ACR 12]. This statement must be moderated, however, in view of the increase in practices involving radionuclides. The next radionuclides to be used will be beta and especially alpha emitters, which have a limited range in living matter. Recently, research is therefore exploring a number of products under development using isotopes such as lutetium-177, promethium-149, bismuth-212, bismuth-213, astatine-211, radium-223 and polonium-210.
1.3.3.4. Harmfulness of radioactive waste
For France, the IRSN [IRS 18b] proposes a methodology and possible criteria for assessing the harmfulness of radioactive materials and waste. In order to make the indicators understandable to a wide audience, the situations are defined to respect a minimum degree of realism. Their choice also aims to cover the main exposure routes and a diversity of contexts.
Four situations are considered, the first two of which involve the presence of an individual in a room containing a package of radioactive waste or radioactive material, whether intact or damaged. The last two situations concern the dispersion of the package in the environment and the impact on an entire local human population or the impact on an aquatic ecosystem.
The report also provides an example of the application of the method for three families of waste (vitrified HA, bituminous MAVL and FAVL 14C). The annual impacts after 100 or 1,000 years are provided and proposals are made for broader deployment, making it possible in the long-term to have an indication of the harmfulness of each of the families defined in the national inventory of radioactive materials and waste [IRS 18b].
1.3.4. American classification
The American classification of radioactive waste has three classes (A, B and C) based on the maximum activity of a given radionuclide (Table 1.2).
Table 1.2. Excerpt from the US NRC classification of radioactive waste based on maximum concentrations of radionuclides and expressed in Ci.m-3 (source: [BLA 01]). MC: maximum concentration (no limit for this class)
Radionuclide | Class A | Class B | Class C |
3H | 40 | MC | MC |
14C | 0.8 | – | 8 |
60Co | 700 | MC | MC |
90Sr | 0.04 | 150 | 7,000 |
99Tc | 0.3 | – | 3 |
129I | 0.008 | – | 0.08 |
137Cs | 1 | 44 | 4,600 |
All radionuclides with half-life <5 years | 700 | MC | MC |
α emitters with a half-life >5 years | 10 | 100 | |
241Pu | 350 | 3,500 | |
242Cm | 2,000 | 20,000 |
1.3.5. British classification
The British classification of radioactive waste adopts the IAEA classification into five categories by defining its own criteria for activity levels (Table 1.3).
Table 1.3. The British nuclear waste classification system (source: [OJO 14, RAH 15])
Waste classes | Characteristics of this class |
VLLW, small volume | Waste of 0.1 m3 that can be disposed of with regular garbage if it contains less than 400 kBq of activity, as well as hospital and university waste. For waste containing carbon-14 and tritium, the activity limit is 4,000 kBq |
VLLW, large volume | Radioactive waste with an upper limit of 4 MBq per ton (not including tritium) is disposed of in specified landfills. For waste containing tritium, the upper limit is 40 MBq per ton |
LLW | Containing radioactive material other than that suitable for disposal with ordinary waste, but not exceeding 4 GBq per ton of waste or 12 GBq per ton of β and γ activity |
ILW | Waste with radioactivity levels above the upper limits for LLW, but which does not generate heat |
HLW | Wastes in which the temperature can increase significantly due to their radioactivity, so this factor must be taken into account in the design of storage or disposal facilities |
1.3.6. Russian classification
The Russian classification of radioactive waste is based on a division into three classes according to the specific activity of various categories of radionuclides (Table 1.4). The limits of the categories are high.
Table 1.4. Practical classification of radioactive waste in Russia (source: [OJO 14])
Category | Specific activity (Bq.g-1) | |||
Tritium | Beta (except 3H) | Alpha (except transuranium elements) | Transuranium elements | |
Low activity | 106–107 | <103 | <102 | <10 |
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