Science Diplomacy at the International Atomic Energy Agency: Isotope Hydrology,Development,and the Establishment of a Technique

Tracing isotope hydrology

When isotope tracer techniques for analysis of global waters came to the attention of IAEA administrators, isotope hydrology was not yet a consolidated field, though its potential utility was increasingly recognized. The first review article examining isotope tracer techniques in hydrology appeared in 1954. By September 1957, at a conference concerning radioisotopes in scientific research arranged in Paris by UNESCO, a section on tracers in hydrology was organized, including work presented by future Nobel laureate Willard Libby. ¹⁶ However, the principal audience for this conference consisted of specialists who had come to radioisotope use through the nuclear sciences, not the community of practicing hydrologists. This condition—isotope hydrology as a set of techniques not initially wielded by the hydrologists themselves—might explain why reviews of the field have sometimes overlooked these techniques, all while highlighting other major changes to hydrology in the twentieth century such as computer-driven quantification or highly integrated stochastic modeling incorporating hydrosphere, atmosphere, and pedosphere. ¹⁷

New instrumentation was central to the development of isotope hydrology. To investigate direction, velocity, and extent of movement of various waters, hydrologists had long sought tracers: salts and dyes such as fluorescein, with chemical, fluorometric and colorimetric techniques for their detection. As tracers, radioisotopes appeared to have the same if not greater potential to function effectively without absorption into the environment. Furthermore, given the discovery shortly before Second World War of isotopes of oxygen and hydrogen, and Harold Urey’s work in the late 1940s to detail the isotope ratios in all the lighter elements, naturally occurring isotopes offered the possibility of measuring ages of various waters, recharge rates and re-evaporation rates of aquifers, as well as stream and aquifer mixing characteristics. These sorts of potentialities required mass spectroscopy, including the Nier-Johnson mass spectrometer (with double inlet and double collector) for discerning differences in isotopic ratios. ¹⁸

The few research groups in the 1950s investigating isotopic tracers in streams and groundwaters were often associated with the new ‘nuclear geology’ involving application of radioisotopes and radiometric techniques in the geophysical study of the earth. The most important of these groups was centered around Willard Libby, inventor of radiocarbon dating, for which he won the Nobel Prize in Chemistry in 1960. ¹⁹ Libby and his colleagues were among the first scientists to show that not only Carbon-14 but the rare hydrogen isotope tritium—accumulating in the atmosphere due to thermonuclear weapons testing—could be used for geological dating. Several geochemists and geophysicists who would go on to play important roles in isotope hydrology cycled through Libby’s University of Chicago research group during the mid-1950s. ²⁰

Tritium was an especially interesting case. Its advent as a tracer was an artefact of the nuclear age. Libby had with Freidrich Begemann, a young German geophysicist, pioneered its use to answer hydrological questions. By 1958, the United States Geological Survey had followed his lead and begun the study of aquifer recharge time in a field project near Batsto, New Jersey, correcting some of Libby and Begemann’s earliest conclusions while showing the enormous potential of the technique. Another pioneering effort, this one in Israel, used injected Iodine-131 to measure movement of groundwater between wells. While it would ultimately be of importance in the new field, it showed the difficulties of experimental work involving sensitive instrumentation and delicate radiation concentration measurements: the Israeli field team was afflicted by equipment failures and leaks of active water containing injected Iodine-131, confounding measurements of background activity. ²¹

From these varying pioneering efforts came three scientists who brought isotope hydrology to the attention of the IAEA in the form of a proposal for a global tritium survey. The first of the three was Begemann, whose work under Libby in Chicago included the measure of tritium levels in rainfalls after hydrogen bomb tests in 1954 and 1956. The other two scientists involved in the proposal also had a Chicago connection. Hans Suess, another geophysicist, came to Chicago in the mid-1950s to study Cabon-14 dating with Libby, taking up the demanding problem of measuring Carbon-14 levels in gases. He pioneered the field of C-14 geochemistry, examining among other things the increased global levels of C-14 which were also a by-product of hydrogen bomb testing. Erik Eriksson, Swedish geochemist, also found his way to Chicago, developing a method of tritium analysis at the University’s Department of Meteorology. Notably, it was Eriksson who proposed tritium-level analysis for detecting the extent and recharge rates of aquifers. ²²

In the second half of 1958, Begemann, Suess, and Eriksson together finalized an ambitious proposal to globalize isotope hydrology. In it, the three scientists argued that the time had come for a worldwide survey of isotopes in water. This meant examining the ratios of the stable isotopes of hydrogen and oxygen in rain, river, and ocean samples. More urgently, it meant gathering global readings of tritium levels in various waters—the 12.3-year half-life of tritium implied that, if and when atmospheric thermonuclear weapons testing ceased, the window for such hydrological work would also close. Tritium analysis in water systems had already suggested its applicability as a tool for determining the age and size of aquifers, the storage time and flow rates of ground water for the drainage systems of rivers, and the mixing times of ocean water. The three scientists thought that many of these applications could be ‘increasingly valuable for many countries with limited water supplies’. However, the techniques involved were probably out of reach for many countries ‘because measurements of the isotopic composition of water require great technical skill and scientific knowledge’. Furthermore, even with such skill and knowledge, proper interpretation of any data gained would require regional and even global sets of data. The data collection network Begemann, Suess, and Erikkson proposed was correspondingly vast: 100 stations for collection of rainwater, 40 stations on 20 major rivers for river water, and 50 stations for ocean surface waters. ²³

Nuclear enough? The debate over isotope hydrology in the IAEA

At the end of summer 1959, Begemann, Suess, and Eriksson sat down with Henry Seligman in Vienna. Seligman was the IAEA’s newly appointed Deputy Director General (with particular responsibility for Research and Isotopes) as well as the Secretary of the IAEA’s Scientific Advisory Committee (SAC). With radioisotopes Seligman had made his name: previously the head of the Isotope Division at the British nuclear research center at Harwell, he had a reputation as the energetic driver behind an efficient radioisotope production and delivery service. Known alternatively as ‘Mr. Isotope’ and ‘Mr. EuroIsotope,’ it was Seligman who Begemann, Suess, and Eriksson hoped would stir the IAEA to take up their proposal to organize a worldwide network of sample-collecting stations for tritium as well as stable isotopes in water. ²⁴

In fact, with their presentation of the proposal to Seligman, the three scientists stirred something more: institutional reflection on the global aspirations of the Agency. Ultimately, that reflection—what areas of research and applications the IAEA should foster—was a diplomatic one. The IAEA’s preparatory committee (‘Prepcom’), working from the opening of the IAEA treaty for signature to the first meeting of the Board of Governors, had started to emphasize immediately realizable applications of nuclear science rather than nuclear energy. ²⁵ However, the first IAEA Preliminary Assistance Missions, organized to send a team of scientists and engineers to a number of countries in order to evaluate the needs and interests of member states as well as stimulate those interests, had not included any mention of isotope hydrology techniques. ²⁶ Therefore, when Seligman reported the proposal to his colleagues in the IAEA’s SAC, it was the first time that administrators and consultants in the Agency considered the question of whether the IAEA’s purview should include isotope hydrology.

Though only a consultative body, under Seligman’s leadership, the SAC had considerable influence in the early IAEA. The IAEA’s Board of Governors tended to accept its recommendations, especially when seconded by the Director General. Its original membership included several of nuclear science’s most prestigious names, including Nobel laureates I.I. Rabi and John Cockcroft, and Homi Bhabha, president of the 1955 Atoms for Peace conference in Geneva. All of these members had many years’ experience in both the scientific and diplomatic worlds. In fact, three of them (Bhabha, French radiochemist Bertrand Goldschmidt, and Soviet metallurgist Vasily Emelyanov) served on both the SAC and the IAEA Board of Governors, meaning their views of the Agency’s technical difficulties and political disputes were particularly extensive and their influence deep in multiple Agency forums. Which is to say, in the first years of the IAEA, the fusion of science and diplomacy came not only from the nature of the matters with which the Agency dealt—matters in which science and diplomacy were insoluble—but also with the position of some of its key figures in both nominally technical (SAC) and diplomatic (Board of Governors) bodies.

In the SAC’s first meeting held at UN headquarters in New York on the late morning of 14 November 1959, the conversation quickly advanced to a discussion of what principles should guide the topics selected for IAEA-organized panels, symposia, and seminars. Soviet metallurgist Vasily Emelyanov proposed three criteria: subjects adding to the IAEA’s prestige, subjects of interest to the majority of member states, and subjects not covered by other UN organizations. In response, Indian physicist Homi Bhabha argued that it was the maturity of a subject of field that mattered: if there was not yet sufficient data in a given field, then the IAEA should not be involved. The Committee worked through several topics: medical scanning techniques, waste disposal at sea, application of ionizing radiations to chemical problems, small and medium power reactors, use of radioisotopes in industry, and radioactive metrology. French radiochemist Bertrand Goldschmidt suggested that the Committee consider topics ‘helpful to the smaller countries’. This first evocation of a diplomatic criterion was not taken up, however, and the meeting adjourned for the day. ²⁷

When the SAC reconvened the next day, several topics had in fact won endorsement. Notably, it was decided that three of the proposed seminars and conferences should be held in cooperation with other international agencies: medical radioisotope scanning techniques with the World Health Organization, radioactive metrology with the International Commission of Radiation Units (ICSU) and International Organization for Standardization, and training of nuclear specialists with UNESCO. The SAC recommended that two large events be the IAEA’s own, reserving for itself conferences on application of radioisotopes in industry and disposal of radioactive waste. ²⁸ Committee secretary Henry Seligman then opened the day’s principal discussion: a suggestion put forth ‘by three experts who had met in Vienna’ for a worldwide survey of the distribution of hydrogen and oxygen isotopes—Begemann, Suess, and Eriksson’s proposal. Goldschmidt immediately sensed the utility of it and jumped in, stating that ‘a programme of tritium measurement might be useful in providing a general idea of water needs throughout the world’. ²⁹

Goldschmidt’s fellow committee members, however, fought to keep isotope hydrology at arm’s length. Bhabha thought the IAEA should not carry out such a survey, but ‘merely try to encourage interest in the subject’. Rabi grumbled, expressing ‘considerable misgivings about the proposal; its purpose was not clear to him and he could not see who would benefit by it’. He thought the US, the USSR, India, and the countries of Western Europe capable of making the measurements themselves. Emelyanov shared Rabi’s scepticism: ‘The proposal merely showed that certain countries were interested in the use of tritium as a means for measuring changes in water movements. That interest was not shared by the Soviet Union’.

Rabi then added a second, more incisive point. While he did not doubt the proposal’s utility, he could find virtually no link to the IAEA’s mission, just ‘use of isotopes’. When Seligman defended the proposal by appealing to its potential benefit to ‘under-developed countries’ which was, after all, written into the Agency’s charter, Bhabha rejoindered that the problem was more general than this particular ‘use of isotopes’. Otherwise, virtually any use of isotopes could be construed as an Agency project. In the case of the proposal to analyze hydrogen and oxygen isotopes, Bhabha thought it viable only if it could be linked to the world’s nuclear infrastructure, as a means of improving nuclear waste disposal. ³⁰ British chemist Robert Spence (sitting in for John Cockcroft) defended the proposal by alluding not only to its utility to countries ‘with water problems’ but to the Agency’s charge to share new scientific knowledge. Goldschmidt’s reiteration of the proposal’s utility to improving irrigation in ‘less advanced countries’ was not enough to save it. Sterling Cole, chair of the SAC and Director General of the IAEA, expressed personal support for the proposal but declared that the committee as a whole needed more convincing. Any proposal revision should provide more detail about the link between the survey and the work of the IAEA. ³¹

That opportunity came, in Vienna, in early June 1959. In the meantime, Begemann, Suess, and Eriksson, likely with Seligman’s input, revised their proposal for the SAC’s consumption. Two changes were most evident. First, language was added concerning ‘the disposal of radioactive wastes’, claiming that the survey would ultimately inform waste disposal on land and in the sea. Second, collection and even analysis of samples should be done ‘by institutions best fitted for the purpose’. Even in the original proposal, the three had suggested that the UN World Meteorological Organization (WMO) be involved. Here was more specific instruction that collection and analysis be in non-IAEA hands. Begemann, Suess, and Eriksson continued to emphasize the new knowledge to come about the global water cycle as well as groundwater storage. ³²

When it met again in late June 1959, the IAEA SAC had warmed to the revised proposal. Because of changes to IAEA record-keeping, we lose track of individual arguments, but we can continue to observe the fault lines of discussion. ³³ Although there was still objection that ‘a large-scale technical operation of that nature had little connexion with the peaceful uses of atomic energy’, all but one of the SAC members agreed to it. In fact, in the meantime, various member states had begun to express explicit interest in isotope hydrology techniques, and one committee member wondered whether the IAEA should start its efforts in a single location, in order to ‘demonstrate its capabilities in that type of survey’. In a concession to previous worries that the isotope hydrology work had nothing to do with the world nuclear complex, in its final recommendations the SAC added language explaining how the survey would better understanding of the pathways of radioactive waste seepage. The SAC insisted such a global survey be carried out in participation with the WMO as well as various national laboratories and that the Agency’s role be seen as ‘establishing a technique’. The latter was crucial. In its role as coordinator, the IAEA would need to gather experts to agree on the standardization of ‘techniques and measurement’ before extensive fieldwork in isotope hydrology could begin. ³⁴

IAEA Director General Sterling Cole had to hurry to convert the SAC’s recommendation into an item for consideration by the IAEA Board of Governors, who were meeting less than two weeks later. His 17 June 1959 cover letter for the SAC recommendation made two principal arguments for a worldwide survey of tritium and stable isotopes in water. First, coordination of a global project would shed a positive light on the IAEA. In Cole’s summary, several members of the SAC agreed that ‘it was extremely important for the Agency to co-ordinate international activities involving the use of the radioactive substances. It was felt that such a large-scale programme would attract the interest of both Governments and individual scientists to the Agency’. The global survey, that is, might net global allies for the IAEA. Second, oversight of the survey would give credit to the Agency for ‘establishing a technique’. As the SAC had noted, the IAEA would have to standardize techniques and measurements before widespread fieldwork could be accomplished. Positioned at a technoscientific focus, the IAEA would benefit from increased diplomatic clout. ³⁵

Two days after the Director General’s memo, the IAEA Board of Governors convened. Begemann, Suess, and Eriksson’s global survey, transformed by the SAC and the Director General into proposed IAEA project, contained technical and diplomatic promise, but arrived at an unpropitious moment. The IAEA General Conference had already determined the 1960 annual budget, without allocating anything for such a survey. Any funding would have to come from the Agency Operating Fund. For some of the 23 members of the Board, that constituted a considerable difficulty. The Australian governor thought it ‘something tacked on and impossible to fund, despite its merits. The UK governor similarly thought that broaching the survey now constituted ‘a tactical error’, while his US counterpart, assuming the same, resigned himself to hoping it would be reconsidered for the 1961 budget. The Soviet governor, Leonid Zamyatin, declared himself opposed to the ‘large and unjustified expenditure’ and the Romanian governor followed suit. Others echoed previously voiced concerns that the General Conference had not had occasion to approve funding for the proposal. Only the Indian governor, Milton scholar-turned-diplomat Balachandra Rajan, stood unreservedly behind the SAC to affirm that he supported the proposal for worldwide survey of isotopes in rainwater and thought it should be ‘considered on its merits’. ³⁶

Fearing that the Zamyatin and his Romanian counterpart were rejecting the proposal for political reasons, UK governor M.I. Michaels articulated his understanding of those merits:

Judging the merits of the project involved a question of principle. The project was one which could a help a large number of countries which were short of water. It involved research which it would be difficult for any one country to carry out on its own, and some countries to which it would be of assistance might not appreciate the fact that such projects could, in the long run, be more valuable to them than short-term technical assistance with its immediate advantages.

Besides the ‘tactical error’ of untimely submission spotted by M.I. Michaels, the reservations with the worldwide water isotope survey voiced in the Board of Governors as well as the fault lines of debate in the SAC indicated the paradoxes of the IAEA as a new international organization. Bhabha’s point in the SAC about isotope use and Agency activity spelled out one paradox neatly. Virtually any activity with some instrument, material, or data tracing back to various nuclear complexes or simply involving radiation could be construed as ‘atomic’ and therefore considered the IAEA’s business. The United Nations, however, did not intend the IAEA to adjudicate or organize all of humanity’s technology. And while the IAEA statute compelled the Agency’s governors to consider the needs of ‘under-developed areas’ of the world, there was no mention of technical assistance, when, visibly, a definition of IAEA technical assistance would be crucial in considering and meeting those needs. In the General Assembly, the Soviet delegate had already articulated his fear that Western countries might in the name of technical assistance be scheming to dominate or even appropriate embryonic atomic industries ³⁸ —background to the unease Zamyatin manifested with the isotope hydrology proposal. This was not to mention that in forums like the SAC and the Board of Governors, when discussion about techniques like isotope hydrology turned to how those techniques might benefit developing countries, the governors and committee members discussing them were largely, almost exclusively, from more developed ones.

Establishing the technique

The establishment of isotope hydrology as an IAEA concern did not resolve these paradoxes. Rather, these paradoxes themselves suggest the degree to which the development of the IAEA—its isotope hydrology capacity included—was contingent on political, economic, and scientific currents and events. What the SAC and BOG had done in the second half of 1959 was to give isotope hydrology an institutional foothold, meaning further development was possible—but not certain. That it was at least possible was visible elsewhere. By September 1959, UN offices in Southeast Asia had requested a specialist in isotope hydrology join a Preliminary Assistance Mission to the countries of the Mekong River Basin. A month later, the IAEA Bulletin chose to announce the global survey of water isotopes, despite the incomplete support delivered by the Board of Governors. Well that it might. It was increasingly clear that the other techniques the IAEA might provide, such as nuclear power plants, were many years from reality for most of the world. ³⁹

In the coming year, tritium—its potential as a tracer having drawn Begemann, Suess, and Eriksson to approach the IAEA in the first place—worked to force the Agency’s hand. As the tritium deposited by the hydrogen bomb tests of the 1950s continued to decay, Seligman gathered a panel of isotope specialists including not only Begemann, Suess, and Eriksson, but Willard Libby himself, to recommend what the IAEA should do in light of the situation. Besides pushing forward the global survey with the WMO, the specialists recommended the study of particular basins where tritium measurements might immediately contribute to the solution of existing problems, the demonstration of such techniques for interested national agencies, and, crucially, the establishment of an Agency isotope hydrology laboratory in Vienna. ⁴⁰

By then, despite hesitation from Western European countries and opposition from the Soviet Union, the Board of Governors had approved an independent laboratory for the IAEA. By 1961, with substantial assistance from the US, in Seibersdorf, not far from Vienna, the laboratory was up and running, carrying out measurements for standardization, calibration, quality control, and sample analysis. Given the significance of radioisotopes in its daily operations, the addition of an isotope hydrology capacity was not a stretch. This was especially important for tritium measurements, as there were only a few national laboratories worldwide capable of making tritium analyses and none focused on standardization of samples and measurements. Demand for water-tracing services put such a strain on the laboratory’s resources that by mid-year 1961, the Board of Governors agreed to add an additional specialist specifically for isotope hydrology work. ⁴¹

That year—as the worldwide survey of isotopes in precipitation, now approved in full by the Board of Governors, got underway—the IAEA staked a claim on tritium analysis. The IAEA’s major scientific symposium for the year, held in May in Vienna, concerned the uses of tritium in the physical and biological sciences. Held jointly by the Agency and the ICSU Joint Commission on Applied Radioactivity, isotope hydrology featured among the major topics. As organizers highlighted Willard Libby’s role in the origins of the discipline, the 270 scientists present learned about detection of water seepage in canals, tracing of waters in underground systems, and the IAEA-WMO global survey of tritium (and oxygen isotope) levels in rainwater. ⁴²

By the time of the 1961 symposium, the SAC, once ambivalent on the place of isotope hydrology in the Agency, was now fully behind it. Not only had the SAC put its support behind the 1961 symposium on tritium analysis as well as the addition of isotope hydrology to the Seibersdorf laboratory work. It endorsed an international symposium specifically on isotope hydrology for 1964 (in fact, the symposium took place in 1963, in Tokyo), signalling that it viewed the discipline as sufficiently mature. And it recognized isotope hydrology as a key form of technical assistance. ⁴³

Strictly speaking, in 1961 there was only one IAEA technical assistance mission involving isotope hydrology, to Iceland, where analysis was made of hot spring waters. However, ‘the technique’, carried forth by IAEA experts, circulated farther and wider than that. The Mekong Committee, managing a long-term UN special fund project to study and develop the resources of the Mekong River basin, requested two IAEA experts to analyze bed-load movements in the river’s lower reaches. Similar requests had sent Agency experts to central Africa. ⁴⁴

IAEA isotope hydrology’s real proving ground, however, was in Greece. Joining an FAO project already underway, the Agency received $17,000 to explore underground water connections in karstic limestones between the high plateau of Tripolis and the Gulf of Argos, in the Peloponnese. The work began in March 1961, when 1000 cc of tritiated water were injected into a sinkhole at Partheni followed by measurements of the tritium closer to the sea at the spring at Binikovi. The IAEA scientists, making tritium analyses in the Seibersdorf laboratory, were able to ascertain a connection between the springs as well as to get a sense of the storage time of the aquifer being studied. While scientists questioned the use of injected tritium, the experiment demonstrated (and a subsequent test nearby early the next year confirmed) the principle: tritium tracers could provide otherwise unattainable information about aquifer extent, flow, and storage time. ⁴⁵

By that time, the FAO had reached an agreement with the IAEA to include isotope hydrology in all UNDP-funded large-scale groundwater programs. It was one indicator that a feedback loop had started to function. As isotope hydrology techniques and uses were refined, as the IAEA’s own isotope hydrology section became more central to their standardization, and as IAEA experts circulated with more regularity, more international agencies and member states called upon those increasingly visible capacities. (The action in Greece also happened to bring the Seibersdorf laboratory its first payment for services.) The change this brought was audible in the Board of Governors. In March 1962, when the Australian governor called into question the place of isotope hydrology in the IAEA, the Tunisian governor shot back that the developing countries stood to gain from the technique, with the Director General (now Sigvard Eklund) adding that he ‘could not agree with [the Australian representative] that problems relating to the use of radioisotopes in hydrology lay outside the scope of the Agency’s activities: considerable service had already been rendered to some Member States in that field’. The convening of the IAEA’s first official panel dedicated to isotope hydrology in November 1961 also drove home the point. As hydrologists and isotope specialists strove to bridge the gap between their disciplines, the superiority of isotope tracers to dyes or salt tracers appeared equally clear, and tritium’s use in estimating the age and recharge rate of groundwaters exploitable. As the Panel’s conclusion noted, the expense involved in such analysis was minor compared to ‘the rather large capital investment required for full scale utilization of groundwater’. ⁴⁶

By the early 1960s, Begemann, Suess, and Eriksson’s intervention that led to the Global Network of Isotopes in Precipitation (GNIP), too, echoed into the future. The GNIP grew considerably, from 100 detection stations in 1961 to over 200 in the next two years. The Isotope Hydrology section of the Seibersdorf laboratory was the central fulcrum of this greatly dispersed IAEA-WMO effort.

Technical and Diplomatic Tensions

Meanwhile, IAEA technical assistance work in isotope hydrology continued to unfold, not only in Greece, but elsewhere. A short mission in Iceland in early 1963 featured construction of a mass spectrometer for the examination of the stable isotope ratios in geyser waters. A mission beginning later that year in Kenya tacked closer to the diplomatic aims of the SAC and Board of Governors. Next to Lake Chala, within sight of Mount Kilimanjaro, IAEA experts took tritium measurements as well as evaluated stable oxygen and hydrogen isotopes, with the goal of evaluating the lake waters for use in the local Kenyan irrigation system. In fact, this work would continue for five years, ultimately demonstrating that waters of Lake Chala, well off the global meteor line, were not contributing to the recharge of nearby springs. ⁴⁷

Early the following year, in Tunisia, another IAEA technical assistance mission in isotope hydrology took place. It was characteristic of many to come. For two weeks, J.G. Guizerix and B. Gaillard organized radiotracing techniques to measure the flow of waters. In Tunisia, the goal was not site specific. Rather, working with technicians from the Tunisian atomic energy commission and the office of hydraulic research and record-keeping, the two French isotope specialists hoped to create the seed of a long-term isotope hydrology capacity in the Tunisian administration. With that in mind, Guizerix recommended continued training of Tunisian technicians and reliance on tritium to minimize radiation risks. (He thought it particularly important that tritium’s low-energy beta activity posed less risk than other injected radioisotopes.) ⁴⁸

When the IAEA’s working group on hydrology programs met later that spring, the difficulty involved in extending isotope hydrology to developing countries was visible. Part of that difficulty was a matter of techniques and disciplines: the great majority of participants were isotope specialists, not hydrologists. National atomic establishments and nuclear geology institutes still supplied most specialists in the field, and a gap persisted between them and ‘conventional’ hydrologists. That was one cause of another, related difficulty. As of 1964, there were still no developed countries represented in the IAEA working group. This contrasted with the healthy representation from East and West, the former including scientists from Czechoslovakia, Romania, and Yugoslavia. ⁴⁹

The meeting served as an opportunity to build on the Tokyo symposium and to continue to define and discuss the most important problems in isotope hydrology: evaluation of water flows, groundwater dating, measurement of evaporation and suspended sediments, and selection of isotopic tracers. ⁵⁰ The range of practical problems the solution of these problems could lend themselves to was equally fascinating: tracing sewage and irrigation channels, measuring the flow of water to power-generating turbines, evaluating more generally the flow of streams large and small (especially for large flows, isotopic tracers proved superior to chemical or other tracers), judging the stability of sands serving as a lighthouse foundation (Denmark), or, as in France, tracing the likely path of effluents from a plutonium processing plant (the future plant at La Hague). ⁵¹

Perhaps most interesting for developing countries was a technique described by J.G. Guizerix, who earlier that year had represented that IAEA in Tunisia: ‘There are leakage problems which can only be solved with radioisotopes…[in] reservoirs, tanks, hydro-electrical barrages, irrigation, grand canals’. Guizerix himself had carried out such studies for Electricité de France, downstream of its hydroelectric dams. However, he lamented, ‘Not many people are interested in this problem’. That ‘problem’ just as Guizerix described had the potential to involve dozens of developing countries. In North Africa alone, Tunisia and especially Morocco undertook massive dam-building efforts in the 1960s and 1970s, as did many other countries worldwide, all aiming to increase agricultural and municipal water supplies as well as to add hydropower to their energy profiles. ⁵² The scientists in the working group did not show immediate evidence of awareness of the potential of their techniques in this regard. ⁵³

Nevertheless, they did evidence awareness of the diplomatic potential of their field. When one of the scientists suggested coordinating observations worldwide to test major theories, Brian Payne, who was after all head of the IAEA hydrology section and closest to international science diplomacy currents, burst out, ‘[it] could be done with the Hydrological Decade!’ He then proceeded to describe the opportunity that the coming International Hydrological Decade (IHD) provided for adding isotopic data to the mass of other data which the UNESCO-coordinated program would produce. The opportunity was at once scientific and diplomatic, moving the IAEA onto the world stage in a key UN plan. ⁵⁴

Conclusion

Indirectly, of course, Payne’s suggestion transformed into a signal to developing countries that isotope hydrology could serve their purposes. While UNESCO sponsored the IHD (1965–75), within that program, it was the IAEA who took leadership of isotope hydrology research and applications. The IHD stated that it put equal emphasis on research and techniques to benefit developed and developing countries, but when listing the IHD’s accomplishments the latter projects, often in coordination with the UNDP, predominated. ⁵⁵ Institutionally, the IAEA came gradually to grasp the weight isotope hydrology carried in the developing world. As IAEA historian David Fischer put it 30 years later, there were two Agency programs that assuredly benefited developing countries: isotope hydrology work and the IAEA sterile insect program. ⁵⁶

IAEA technical assistance, isotope hydrology included, played a unique role in the IAEA’s diplomatic profile, as this essay has shown. From the beginning, the IAEA struggled to define itself, caught between two seemingly opposing missions: (in the words of a Romanian representative in 1959) ‘a control organ’ and ‘a body specializing in assistance’. ⁵⁷ Given that other UN bodies also provided assistance of various sorts, David Fischer asks a ripe question. Since, after all, the World Health Organization, the Food and Agricultural Organization, the WMO, and other UN agencies could have assumed the technical assistance work taken on by the IAEA, why weren’t all of those areas of technical assistance lopped off it, leaving the Agency with a clear, narrow mission of nuclear safeguards? Fischer’s answer is political:

[I]f the IAEA’s only role were to administer safeguards it would be regarded chiefly as an instrument that the nuclear weapons States use to deny other States the possession of nuclear weapons … in the meantime [before all nuclear weapons are eliminated] the assistance that the IAEA has given to the developing world has softened the image of a guardian …

There are two brief final points. First, it is clear that the process that brought isotope hydrology firmly into the suite of IAEA technical assistance techniques and extended it to developing countries was a gradual and contingent one that merits more study. Such technical assistance missions following the 1964 working group meeting (Chile, 1964–5; Morocco, 1969–70) suggest such missions often required extension of the original time allotted. Training of specialists in isotope hydrology was not easier. While IAEA symposia began to attract an increasing number of scientists from developing countries, ⁵⁹ actual training courses were exercises in learning for teachers and students alike. Organizers of the 1967 Interregional Training course in Ankara discovered that they had frontloaded the program with basic hydrology and isotope instruction and left too little time for lab and field work. The sole archived participant’s report from the meeting suggests the IAEA’s forte—isotopic tracers—deserved all the attention. In it a hydrological engineer from Taiwan reported that ‘the trainees were all hydrologists’ and did not require the several days spent on hydrology. All of which suggests that historically tracing the integration of the use radioisotopes into hydrological practice requires research of the local contexts in which it took place. ⁶⁰

Second, this brief analysis ignores other powerful factors that deserve attention. The IAEA’s assumption of authority in the area of isotope hydrology soon also became one way by which the Agency could claim relevance in discourses concerning the planetary environment and its preservation—yet there is little historical analysis of the IAEA’s position in environmental history. And, the IAEA’s assumption of technical authority in this case must be understood in the context of the IAEA’s work in the field with UNESCO, the FAO, the WMO, the UN Water Resources Development Centre, and the UNDP. Further research will be necessary to better appreciate what role isotope hydrology had in navigating those relationships, which likely involved competition and cooperation. Further research will be needed, too, to consider the place of isotope hydrology in larger diplomatic initiatives: as we increasingly comprehend science diplomacy as not simply a benign alternative to other diplomatic tools but as an integrated part of diplomatic relations, then certainly we must take another look at the diplomacy of isotope hydrology, which after all carries with it hard economic and social implications regarding water resources and availability.

One thing is certain: any study of the further development of IAEA isotope hydrology must admit that contingency, contestation, and diplomatic necessity will continue to displace any notion of technological inevitability.