The amount of LLW existing at present in Scotland and that which is esti­mated to arise during the operational and decommissioning lifetimes of the

nuclear facilities is given in Table 17.2. This amount of LLW is around 6% of the UK predicted total of LLW to arise (NDA, 2011a). The LLW volume estimated to arise and require disposal is dominated by the decommissioning activities on the NDA estate, being 90% of the Scottish total. A large percent­age of the LLW arising from NDA sites’ decommissioning activities, and that which will arise when the operating nuclear power stations undergo decom­missioning, is in the form of concrete, rubble and lightly contaminated metals. This often has radioactivity levels significantly below the maximum limits for LLW of 4 GBq/te alpha and 12 GBq/te beta/gamma. There is opportunity for decommissioning sites to explore routes other than to LLWR for disposal of this type of LLW rather than using up valuable space in the LLWR.

LLW of similarly low radioactivity, but generated in very small quantities from hospitals and universities is termed very low level waste (VLLW). It is able to be disposed of safely along with municipal waste.

The regulatory system for SNF and radioactive waste management in the United States involves several agencies: the Nuclear Regulatory Commis­sion (NRC), regulating the commercial nuclear sector; the Environmental Protection Agency (EPA), establishing environmental standards; and the DOE, regulating government programs. Some NRC regulatory authority — excluding SNF, special nuclear material sufficient to form a critical mass, and HLW — can be delegated to the 50 states of the United States and the territories Puerto Rico and the District of Columbia under the Agreement State Program. This authority includes regulating commercial LLW disposal sites and uranium mill tailings sites, and regulatory authority over the dis­posal of mill tailings. Some states also have regulatory authority delegated to them by the EPA, such as for discharges from some industrial or mining practices.

Table 18.1 Key US laws governing RAW management

Atomic Energy Act of 1954, as amended, established the Atomic Energy Commission, the predecessor to the Nuclear Regulatory Commission and the Department of Energy, with federal responsibility to regulate the use of nuclear materials including the regulation of civilian nuclear reactors. Under Reorganization Plan No. 3 of 1970, which created the US Environmental Protection Agency (EPA), authority to establish generally applicable environmental standards was transferred to the EPA along with authority to provide federal guidance on radiation protection matters affecting public health.

The Price-Anderson Act (1957) was enacted to encourage development of the nuclear industry and ensure prompt and equitable compensation in the event of a nuclear incident. The Act provides a system of financial protection for persons who may be liable for, and persons who may be injured by, such an incident.

Solid Waste Disposal Act of 1965, as amended, requires environmentally sound methods for disposal of household, municipal, commercial, and industrial waste. The Resource Conservation and Recovery Act is an amendment to the Solid Waste Disposal Act.

National Environmental Policy Act of 1969, as amended, requires federal agencies to consider environmental values and factors in agency planning and decision making.

Clean Air Act of 1970 is the comprehensive federal law that regulates air emissions from stationary and mobile sources.

The Marine Protection, Research, and Sanctuaries Act of 1972, also known as the Ocean Dumping Act, prohibits the dumping of material into the ocean unreasonably degrading or endangering human health or the marine environment.

Safe Drinking Water Act of 1972, as amended, protects public health by regulating the nation’s public drinking water supply; it requires actions to protect drinking water and its sources: rivers, lakes, reservoirs, springs, and groundwater wells.

Energy Reorganization Act of 1974, as amended, abolished the Atomic Energy Commission and established the Nuclear Regulatory Commission and the Energy Research and Development Administration — the predecessor of the DOE.

Resource Conservation and Recovery Act of 1976, as amended, regulates the handling and disposal of hazardous wastes, which are generated mainly by industry, also requires that open dumping of all solid wastes be brought to an end throughout the country by 1983.

Department of Energy Organization Act (1977) brought together most of the Government’s energy programs, as well as defense responsibilities that included the design, construction, and testing of nuclear weapons into the new Department of Energy. The Department was established on 1 October 1977, assuming the responsibilities of the Federal Energy Administration, Energy Research and Development Administration, the Federal Power Commission, and parts and programs of several other federal agencies.

Uranium Mill Tailings and Radiation Control Act of 1978, as amended, vested the EPA with overall responsibility for establishing health and environmental cleanup standards for uranium milling sites and contaminated vicinity properties, the Nuclear Regulatory Commission with responsibility for licensing and regulating uranium production and related activities, including decommissioning, and the Department of Energy with responsibility for remediating inactive milling sites and long-term monitoring of the decommissioned sites.

Table 18.1 Continued

Comprehensive Environmental Response, Compensation, and Liability Act of 1980 as amended, also known as Superfund, provided the EPA with authority to address abandoned hazardous waste sites and outlined the process to be followed in identifying and remediating sites, including determination of cleanup levels and pursuit of contribution to the cleanup or cost recovery against parties deemed to have contributed to the contamination. It includes radionuclides as a hazardous substance.

Low-Level Radioactive Waste Policy Act of 1980 and Low-Level Radioactive Waste Policy Amendments Act of 1985 gave individual states — rather than the federal government — responsibility to provide disposal capacity for commercial Class A, B, and C low-level waste; authorized the formation of regional compacts (groups of states) for the safe disposal of such low-level waste; and allowed compacts to decide whether to exclude waste generated outside the compact. The acts gave the federal government responsibility for the disposal of greater-than-class C low-level waste that results from activities licensed by the NRC or Agreement States.

National Security and Military Applications of Nuclear Energy Authorization Act of 1980. Section 213 (a) of the Act authorizes Waste Isolation Pilot Plant ‘for the express purpose of providing a research and development facility to demonstrate the safe disposal of radioactive wastes resulting from defense activities and programs of the U. S. exempted from regulation by the US Nuclear Regulatory Commission.’

West Valley Demonstration Project Act of 1980 authorized the DOE to conduct a technology demonstration project for solidifying high-level waste, disposing of waste created by the solidification, and decommissioning the facilities used in the process. The Act required the DOE to enter into an agreement with the State of New York for carrying out the project.

Nuclear Waste Policy Act of 1982 as amended by the Nuclear Waste Policy Amendments Act of 1987 establishes the federal responsibility for disposal of spent nuclear fuel and high-level waste.

Waste Isolation Pilot Plant Land Withdrawal Act of 1992, as amended, withdraws land from the public domain for operation of the facility; defines operational limitations and the role of the EPA and the US Mine Safety and Health Administration; exempts transuranic mixed waste destined for disposal at the facility from treatment requirements and land disposal prohibitions under the Solid Waste Disposal Act. The Act provides for a continuing EPA oversight role, including recertification that the facility meets EPA standards.

Energy Policy Act of 1992 mandated site-specific public health and safety standards and site-specific licensing requirements for the proposed repository at Yucca Mountain, Nevada. Among other things, it also authorized the DOE to reimburse certain ‘active’ uranium and thorium milling owners for a portion of their remedial action costs.

Energy Policy Act of 2005 sets forth an energy and development program and includes specific provisions addressing, among other things, disposal of greater — than-class C low-level waste (including certain sealed sources), naturally occurring radioactive materials, and accelerator-produced waste.

Title 10 (for NRC and DOE) and Title 40 (for EPA) of the US Code of Federal Regulations (CFR) contain the general requirements for the three federal agencies responsible for regulating radioactive waste. US govern­ment regulations are developed through an open process, including the opportunity for public comment. New regulations are published in the Federal Register in proposed and final forms.

The separation between the EPA standard-setting function and the NRC ’s implementing function reflects a nearly 40-year-old congressional policy of centralizing environmental standard-setting in a single agency. When the EPA was established, it was given environmental authorities previously scattered among several older agencies, including the NRC pred­ecessor, the Atomic Energy Commission (AEC). There are advantages to having an agency both set and implement standards, and the NRC does so in many subject areas, especially in reactor design and operation. Nonethe­less, there are also advantages to having environmental standards set on a national basis by a single agency whose jurisdiction is wide enough to permit the agency to rank risks from many sources, including nuclear.

LLW is radioactively contaminated material that is not HLW, SNF, TRU, byproduct material, or naturally occurring radioactive material (DOE, 2009). Under the AEA, the DOE is self-regulating with regard to LLW. Mixed low-level waste (MLLW) is LLW that also contains a hazardous component and is, therefore, subject to a dual regulatory framework, under the AEA, including DOE Order 435.1, Radioactive Waste Management, as well as federal or state hazardous waste requirements promulgated under RCRA (DOE, 1999 ).

The strategy to deal with LLW and MLLW is:

• continue to utilize a combination of DOE onsite, DOE regional, and commercial disposal facilities

• complete an Environmental Impact Statement (EIS) for commercial GTCC waste and issue ROD for GTCC disposal facility

• reuse/disposition contaminated nickel

• build new onsite CERCLA cells

• continue to pursue treatment alternatives for wastes currently inciner­ated at the Toxic Substances Control Act Incinerator at the Oak Ridge Reservation in Tennessee

• continue to develop disposition plans for remaining legacy MLLW and LLW, eliminating waste acceptance and/or transportation barriers.

The DOE produced the Final Waste Management Programmatic Environ­mental Impact Statement (EIS) for Management, Treatment, Storage, and Disposal of Hazardous Waste in 1997 (DOE, 1997). The associated complex­wide decisions for treatment and disposal of LLW and MLLW were issued in 2000. These documents described the approach EM would use to elimi­nate the inventory of legacy LLW and MLLW, the latter in accordance with applicable regulatory agreements. As Table 18.5 illustrates, the DOE has an estimated 1.2 million m3 of LLW and MLLW.

While treatment and disposal of most LLW and MLLW are now routine, the DOE has inventories of both that lack readily available disposition options. The DOE is focusing on developing pathways for this waste. One category of waste for which a disposal solution has been developed is ‘silo material’, generated at the Fernald Site in Ohio. This waste was a byproduct of uranium processing, and the radium it contained emitted large amounts of radon. As a result, it was stored in heavily shielded concrete silos. Because of the nature of this material and the regulatory framework surrounding it, it required a specialized license.

The DOE worked closely with a vendor and state regulators in Texas to allow storage of the Fernald silo material at a Texas commercial facility. Removal of the silo material allowed the DOE to close the Fernald site on schedule in 2006 and greatly reduce the environmental risk of continued storage there. The vendor subsequently applied for a disposal license for this type of material and received the requested permit from Texas regula-

tors in 2008. The disposition path for the Fernald silo material is now final­ized and approved.

To complete cleanup of the Rocky Flats Plant in Colorado, the DOE supported technology development to decontaminate 1,500 gloveboxes suf­ficiently to allow equipment to be disposed of as MLLW or LLW. Glove — boxes are sealed chambers in which workers handle plutonium using long rubber gloves that extend through portholes. They range in size and can be as large as a bus. Previous disposition plans called for the gloveboxes to be reduced in size (cut into smaller pieces), packaged, characterized, and certi­fied for disposal at WIPP. This revised approach significantly reduced work exposure to contamination, workplace hazards, and associated costs.

DOE EM has the lead for developing the EIS for the disposal of GTCC low-level radioactive waste and GTCC-like waste. GTCC waste is LLW resulting from US NRC-licensed activities with radionuclides that would be dangerous to humans beyond 500 years. This waste stream comprises materials such as radioactive sources commonly used to sterilize medical products, detect flaws and failures in pipelines and metal welds, and serve other industrial and medical purposes. These materials were generated, owned, or managed by commercial entities rather than the DOE. However, the Low-level Radioactive Waste Policy Amendments Act of 1985 assigned the federal government responsibility for the disposal of certain GTCC radioactive waste resulting from US NRC-licensed activities.

GTCC waste is the highest radiological activity waste with no planned disposition path. The DOE is preparing an EIS to evaluate disposal options for commercial GTCC LLW as well as LLW similar in character to GTCC generated by the DOE. The DOE issued a Notice of Intent to prepare the EIS in July 2007. A draft EIS was issued by the DOE in February 2011, and a final EIS is expected to be released in 2013. By law, before the DOE makes a final decision on the disposal alternative(s) to be implemented, the agency must submit a report to Congress and await Congressional action before making a final disposal decision.

Contaminated nickel from the shutdown of gaseous diffusion plants is a potentially valuable asset. The DOE is evaluating the feasibility of recover­ing the nickel for potential sale to an end user rather than disposing of it as LLW.

LLW is waste with low long-lived radionuclide concentrations and interme­diate short-lived radionuclide concentrations. LLW consists of waste con­taminated with unirradiated uranium from the NFC and waste contaminated with irradiated uranium in the form of activation and fission products from isotope production and the operation of the SAFARI research reactor and short-lived sealed sources with limited activity levels (sealed sources that would not exceed the inherent intrusion dose of 10 mSv/a after the institu­tional control period).

The long-lived radionuclide (Ti/2 > 30.2 years) concentrations are limited to 400 Bq/g and 4,000 Bq/g for a and в у emitters, respectively. Factor of ten higher concentration levels are allowed per waste package. Deviation from the above long-lived radionuclide concentration criteria is justifiable in the case of a specific repository if the inherent intrusion dose is less than 10 mSv/a after the institutional control period. For LLW with higher con­centrations of short-lived activation and fission products, containers are shielded to ensure surface dose rates of <2 mSv/h. LLW could be pre-treated in unshielded containers in case the surface dose is <2 mSv/h or if the surface dose rate will be <2 mSv/h after waste treatment (e. g., decay). LLW shall be processed to ensure a solid waste form and a waste package that is in compliance with the approved waste acceptance criteria (WAC) of the national near-surface repository of South Africa (Vaalputs) that is suitable for handling, transport and storage for a period of 10 years. LLW shall be disposed of at Vaalputs near-surface repository.

To ensure its safe discharge into the environment, liquid radioactive waste has to fulfill very strict requirements connected with the limits of radioac­tive substances and other impurities (suspended particulates, chemical, bio­logical, heavy metals, etc.). To achieve the standards described in national

regulations, radioactive waste has to be treated, including volume reduction and reduction of radioactive compounds and other solutes in the effluent.

NPPs currently in operation in Korea have their own gaseous, liquid, and solid waste treatment facility and on-site storage facilities to ensure the safe management of RAW generated in the process of operation. The gaseous waste treatment system comprises gas decay tanks and/or charcoal delay beds. The liquid waste treatment system is equipped with either liquid waste evaporators or selective ion exchangers. The solid waste treatment facility has spent resin drying systems, spent filter processing and packaging systems, concentrated waste drying systems, and dry waste compactors. The RI waste generated from domestic medical research, industrial RI users, and research institutes is collected and stored at the Central Research Institute (CRI) of KHNP in Daejeon. Around 90% of LILW comes from NPP and the rest arises from industry, medicine, and research institutes.

Generally, the type of LILW is classified as follows:

• power plants: dry active waste, spent resin, spent filter, and concentrated waste

• non-power plant sources (RI waste): dry active waste (combustible or non-combustible), hepatitis waste, organic liquid waste, spent sealed source, spent resin, spent filters, and concentrated waste.

Figure 21.3 summarizes the process steps for treatment of solid, liquid and

gaseous wastes in Korea.

Radioactive waste (RAW) is generated by the research, development and utilization of nuclear energy at NPPs, nuclear fuel cycle facilities, test and research reactors, universities, institutes, and medical facilities, using accelera­tors, radioactive isotopes (RI) and nuclear fuel materials. It is essential that activities associated with research, development and utilization of nuclear energy also process and dispose of the RAW in such a way as to prevent any significant effects on the human environment now and in the future.

The generation that has enjoyed the convenience and benefits of nuclear energy assumes the responsibility to expend all efforts for safe disposal of RAW for the next generation. There are four principles for the treatment and disposal of RAW:

1. The liability of generators,

2. Minimization of radioactive waste,

3. Rational treatment and disposal,

4. Implementation based on mutual understanding with the people.

Under these principles, it is important to appropriately classify the wastes and treat and dispose of each classification safely based on the recognition that the wastes may include materials with characteristics that take an extraordinarily long time for the radioactivity to drop to insignificant levels2.

A near-surface disposal facility already operates for most of the low-level radioactive waste (LLW) generated at NPPs and is operated in Rokkasyo, Aomori-Ken by Japan Nuclear Fuel Limited (JNFL), as a private business, excluding part of the LLW. With regard to near-surface disposal of RI and research wastes, the Japan Atomic Energy Agency (JAEA) will conduct and promote disposal activity in cooperation with the government and other waste generators. As for the remaining LLW, JNFL plans to construct an intermediate depth disposal facility for NPPs and the Nuclear Waste Man­agement Organization of Japan (NUMO) will geologically dispose of transuranic (TRU) wastes. Funds from the owner of the reprocessing plant and mixed oxide (MOX) fuel fabricator, etc., have been accumulating via a levy to pay for geological disposal of TRU wastes since 2009. However, the implementing body for subsurface disposal of LLW, RI and research wastes has yet to be decided.

High-level radioactive waste (HLW), generated during reprocessing spent fuel (SF), is being vitrified and packaged prior to disposal in a geo­logical repository. Research and development for that purpose had been conducted mainly by what was the Power Reactor and Nuclear Fuel Devel­opment Corporation (PNC), which was restructured as the JAEA in October 2005 through the Japan Nuclear Cycle Development Institute. The government worked to develop a disposal system taking into consideration these policy guidelines and scientific evidence, and enacted the Specified Radioactive Waste Final Disposal Act in June 2000. NUMO was created in October 2002 as an implementing body for disposal, as specified in the Act. In December 2002, NUMO started ‘open solicitation’, which encouraged municipalities to consider investigating the suitability of their local area for developing a deep repository for HLW. Meanwhile, electric utilities and others have been accumulating funds for the disposal of HLW.

Radioactive noble gases (e. g., krypton and xenon) and volatile fission prod­ucts (e. g., iodine and cesium) were the main constituents of the radioactive materials released into the atmosphere during the Fukushima accident [24]. Of all the noble gases, krypton-85 has the longest half-life (10.8 years) and

24.2 Potential migration of radionuclides in atmospheric, terrestrial, and aquatic systems [23]. Used with permission from The American Association for the Advancement of Science.

will remain in the atmosphere for a very long time due to its high chemical stability. In general, the inhalation of krypton-85 by animals or humans adversely affects the organs of the respiratory system. However, taking into account that we are naturally exposed to much extensive inhalation of radon and daughter nuclides, and that a considerable amount of krypton-85 has already been accumulated in the air by artificial activity, the effect of krypton-85 by this accident is considered to be limited. Radioactive materi­als containing iodine, cesium and other radionuclides are often carried by air particles and subsequently introduced by wet and dry deposition into the terrestrial environment. Radionuclides behave differently in the ter­restrial environment. Some of them (such as cesium and iodine) are mobile in the environment and can easily be transferred into the water supply and food chain [25] . Other radionuclides have low solubility (such as the acti­nides) and can largely be retained in the soil [26] . The main transfer path­ways of radionuclides in the terrestrial system are shown in Fig. 24.3.

The marine environment was affected by aerosols emitted into the atmos­phere and then deposited on the ocean, as well as by the direct release of seawater used for cooling the reactors. In the future, leaching from contami­nated soils will be the main source of pollution into the marine environ­ment. The mobility of radionuclides transferring between atmospheric, terrestrial, and aquatic systems increases the scope of their adverse influ­ences to a wide variety of living organisms and ecological processes.

During surveys of the territories of Semipalatinsk nuclear test site by Amer­ican satellites NOAA-14 and NOAA-15, experts at the National Nuclear Centre of Kazakhstan detected large-scale surface temperature changes (Zakarin et al., 1997; Sultangazov et al., 1997). Their findings indicated the presence of a regional thermal anomaly with a surplus temperature of about 10°C in an area which was over 20,000 km2, i. e., the entire area of the landfill including the sites of Degelen and Balapan. The presence of such a thermal anomaly was assured to be associated with increased activity of the earth surface and the active mechanism of ‘smoldering’ reactions of nuclear fission. It is hypothesized that, under the influence of gamma radiation in the atmospheric boundary layer, reactions occur that result in a certain part of the oxygen being converted into ozone (Melent’ev and Velikhanov, 2003). Since ozone is heavier than air, it is concentrated at the surface of the Earth and, having been an active oxygenator, produces detrimental effects on biological systems. This effect is confirmed by the images obtained from satellites: there is practically no vegetation in the places that experi­enced these higher temperatures. Publications on this issue are the subject of much scientific debate. It is clear that the parts of the Earth’ s surface exposed to nuclear explosions should be looked at in more detail to examine the structure of the thermal field at the landfill, in order to draw attention to the complex combination of natural conditions and radiation effects, taking into account the low spatial resolution of the apparatus of NOAA satellites.

In addition, these influences are manifested at the ground surface (under certain conditions they can be observed visually, such as when snow melts in the warmer parts of the area). However, all processes associated prima­rily with the underground migration of radioactive products in the aqueous and hydrocarbon layers (including the partitioning of radioactive products in the area of the boiler cavity from a melt solution, and their contamination of surface and groundwater) and changes in the hydrological regime of aquifers are hidden from the naked eye.

The articles by Kiryukhina and Shahidzhanov (2003) and Bakharev et al. ( 2002 ) specifically note the possible effects of long-term exposure of ele­ments of the cavity to radionuclides and the post-explosion collapse of aquifers after different times. In this case, additional man-made caverns and aquifers contaminated with radionuclides may produce an ever-expanding contaminated area in concert with the natural aquifer system. It is noted that the radiation risk can increase substantially if the boiler starts to accu­mulate karst cavities or other water, that interacts with calcium oxide which can serve as a basis for the formation of liquid radioactive brine (calcium hydroxide), which is able to penetrate sufficiently large distances, up to the upper layers of aquifers. With technological processes occurring near such cavities, the removal of radioactive material to the surface should not be excluded. In limestone-containing rocks, these processes can be exacer­bated by the fact that it is likely that the crushed pile containing calcium oxide and carbon dioxide will expand and will be distributed through per­meable systems and brought to the surface through increased fracturing.

Observations on the migration of radioactive products from underground nuclear explosions carried out in permafrost conditions have been described by Golubov et al. (2003) and Kozhukhov and Kukushkin (2003). The distri­bution of radon, tritium, strontium and other radionuclide contents in the water, and gamma radiation in the vicinity of the explosion ‘Crystal’, carried out in 1974 in Yakutia near the diamond-mining quarry known as ‘Udachnyi’, were studied. Measurements were carried out from the epicenter to the quarry (about 5 km) and showed the following:

1. The level of gamma radiation ranged from 9 to 14 micro-R/h, i. e. it did not exceed natural background levels when the whole area was surveyed.

2. The volume of the radon activity in the epicenter, at a distance of 2.5 km, ranged from 400-500 to 1,300-1,400 Bq/m3.

3. In the area of the quarry, the radon content was 200-700 Bq/m3, suggest­ing that the rate of migration of radon in the local soil is low.

4. There is increased concentration of tritium to 220 Bq/l in the epicenter of the explosion.

5. Concentrations of radioactive carbon and strontium in the drained brines on the side quarry of ‘Udachnyi’ are on average 2-3 times higher than the corresponding concentrations in groundwater from technologi­cal wells close to the background level.

6. It cannot be excluded that the permeability of permafrost rocks in this area caused the working quarry horizons to drop to a much greater depth than that of the cavity created by the nuclear explosion, thereby promoting the drainage of underground brines in the vicinity of the cavity wall of a quarry with the formation of the network of flooded cracks with dissolved radioactive products.

Thus, according to Bakharev et al. (2002), each underground nuclear explo­sion site creates a self-generating uncontrolled dumping of radioactive products into the environment that can have a permanent impact on nature and mankind and, therefore, should be regarded as a functioning ‘radiation — dangerous’ object. Evaluation of radiation and ecological safety in this case is connected with the prediction of the secondary impacts of the residual effects of an explosion on the environment and should be based analysis of situations that could lead to further dissemination and redistribution of the radioactive products.

Table 15.2 presents each waste category along with the current identified

long-term management solution. For some categories, the corresponding

long-term management solution is still under study and this issue is addressed in the 2013 National Plan for the Management of Radioactive Materials and Waste (‘Plan National pour la Gestion des Matieres et Dechets Radioactifs’ or PNGMDR), which is a three yearly plan stating, for all radioactive materials and waste in France, the chosen long-term management option, either operational or being researched.

There is no simple and single criterion to classify RAW. There is no overall activity level, for instance, to determine whether a given residue belongs to the SL-LILW category. It is necessary to examine the radioactiv­ity of the different radionuclides present in the waste in order to rank it according to the classification. More particularly, in order to be considered as SL-LILW, the specific activity of each radionuclide in the waste must be lower than the prescribed thresholds in the waste acceptance specifications for the SL-LILW disposal facility (‘Centre de Stockage de dechets de Faible et Moyenne Activite’ or CSFMA; see Fig. 15.1 for the different facilities

Centre de stockage FMA

Siege

Centre de stockage TFA

Centre de stockage de la Manche

Centre de

Meuse/Haute-Marne

15.1 Map of French facilities managed by ANDRA.

managed by ANDRA). In that category, the activity of long-lived radionu­clides is particularly limited.

However, it is possible to indicate a range of specific activities within which each waste category generally belongs. It may be that a specific waste pertaining to one of the above-mentioned categories is not acceptable within the corresponding management system due to other chemical, physical or other characteristics. Such is the case for residues containing significant quantities of tritium (a radionuclide that is difficult to confine or retain) or of sealed sources for medical uses.

A special case also concerns the waste generated by uranium enrichment facilities and fabrication plants of nuclear fuel containing uranium oxide. Their waste residues contain uranium and are compatible with the accept­ance criteria of the CSFMA or, if their activity is very low, with those of the VLLW repository (‘Centre de Stockage de dechets de Tres Faible Activite’, or CSTFA). In the first case, the waste is disposed of at the CSFMA and, by convention, registered as SL-LILW, notably in the national inventory. In the second case, the waste is disposed of at the CSTFA and included in the VLLW category.

In 2009, UK government published a revised UK Discharge Strategy, which updates government policy and describes how the UK will continue to implement the agreements reached at the 1998 OSPAR Convention, and subsequent OSPAR meetings on radioactive substances, particularly the radioactive substances strategy. This builds on the initial UK Strategy, pub­lished in 2002, and expands its scope to include aerial, as well as liquid discharges, from decommissioning as well as operational activities, and from the non-nuclear as well as the nuclear industry sectors. The objectives of the strategy are:

• to implement the UK’s obligations, rigorously and transparently, in respect of the OSPAR Radioactive Substances Strategy (RSS) interme­diate objective for 2020; and

• to provide a clear statement of government policy and a strategic frame­work for discharge reductions, sector by sector, to inform decision making by industry and regulators.

The expected outcomes by 2020 are:

• progressive and substantial reductions in radioactive discharges (to the extent described in the strategy);

• progressive reductions in concentrations of radionuclides in the marine environment resulting from radioactive discharges, such that by 2020 they add close to zero to historical levels; and

• progressive reductions in human exposures to ionising radiation result­ing from radioactive discharges, as a result of planned reductions in discharges.