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Fund providers	Waste		Segregated
					Government
	producers		fund

Fund disbursers/	Waste		Regulators/
Researchers	management		local
	agency		authorities

			National
Researchers	Commercial
					Universities
	companies		research
			agencies

Fig. 8.2. Example of funding arrangements for R&D on radioactive waste disposal – note that this is only one of many funding models. For an overview of regulatory arrangements, see Table 7.1.

may include the research arm of a power utility, or even international agencies with specialised facilities. ‘‘National research agencies’’ includes institutes/laboratories for nuclear research with specialised facilities for handling radioactive materials. They may also include the national geological survey (where this exists) and institutes/laboratories for environmental research.

As indicated by Fig. 8.2, funds flow to the three kinds of R&D organisations from the waste producers and the regulator. National research agencies (often established on a non-profit basis) and universities will also receive government funding, which gives them the ability to pursue their own R&D and, hence, a degree of independence. To avoid conflicts of interest, research organisations (or, alternatively, individual researchers) are usually prevented from working for the implementers and the regulator at the same time, but this is by no means universal (see, e.g., www.jaea.go.jp).

Although there are obviously differences in the main areas of concern to most national radwaste R&D programmes (dependent, e.g., on local geological conditions or repository design), there are several common themes and these will now be examined.

8.2. R&D in specialised (nuclear) facilities

8.2.1. Introduction

One difference between radwaste R&D and ‘‘standard’’ industrial R&D is the focus on radioactive materials. Due to the unique hazards involved, it is common to use specialised facilities to allow the work to be conducted safely. Usually these facilities consist of shielded ‘‘hot cells’’ (see Fig. 8.3) for work on highly radioactive materials – e.g., significant quantities of alpha-emitting radionuclides (e.g., actinides). For less active

Research and development infrastructure

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Fig. 8.3. A so-called ‘‘hot cell’’ – a heavily shielded box for working on highly radioactive material. The operator can work on the box contents by means of the remotely controlled manipulators (note that the window at bottom right is made of very thick lead glass) (image courtesy of Nirex).

materials, purpose-built glove-boxes are often sufficient to both protect the operators and to provide atmosphere control for working on, e.g., the sorption of radionuclides on a reducing host rock (Fig. 8.4). Such facilities are expensive to build, operate and maintain, not least because of the need for safety and the rigorous regulatory regime that applies. The use of radioactive materials in experiments allows the application of specialised radioanalytical techniques that enable minute quantities of radioactivity to be detected. It is only by the application of such techniques, for instance, that it is possible to measure plutonium solubility values of the order of 10 10 mole dm 3.

R&D that is done in this type of facility is described in the following two sub-sections.

8.2.2. Inventory

As noted in Chapter 2, adequate knowledge of the inventory of radionuclides in the waste is essential for all phases of radioactive waste management. Many countries with significant quantities of radioactive wastes now have well developed and publicly accessible national radioactive waste inventories (e.g., Alder and McGinnes, 1994; Nirex, 2002; Andra, 2004). Usually, these have been developed and improved over many

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Fig. 8.4. Sealed glove-boxes in a radiochemistry laboratory. These are used for working on less radioactive material than is used in hot cells and have the added advantage that it is also possible to work under a controlled atmosphere (e.g., very low oxygen content for working on reducing groundwaters and rock) (image courtesy of JAEA).

years using detailed radionuclide assays in facilities at the site of origin of the waste. Where there are special requirements, samples may be sent away for analysis at specially equipped centres.

The radionuclide inventory in HLW and SF is usually derived by calculations using well-tested and validated computer programs. For other types of waste (with the exception of disused sealed sources), the diversity of the waste streams makes the task more difficult and some wastes may need to be subjected to detailed radioanalysis to measure the type and quantity of radionuclides that are present. It is a constant feature of postclosure safety assessments (key drivers for R&D – see details in Chapter 6) that the radionuclides that come closest to the regulatory targets are not ones that would be considered important for any other aspect of radioactive waste management. An example is 129I which is important to post-closure safety because of its long half-life, its mobility in the environment and its high toxicity. Conversely, radionuclides that are all-important for operational and transport safety (e.g., 60Co, 137Cs) are significantly less important as far as post-closure safety is concerned – a consequence of their relatively short half-life.

From this it can be seen that, in addition to driving the R&D programme in general, safety assessments may also drive a programme of investigation into the inventory. Furthermore it is clear that post-closure SAs may introduce a need for inventory information about radionuclides that, in other circumstances, might be given relatively little attention. As noted in Chapters 2 and 6, a consideration for the future is that changes to public policy – such as a commitment to near-zero releases of radioactivity to the environment – will also change the areas of interest in the inventory and may produce a need for additional R&D.