Near the close of the symposium, participants were asked to summarize important ideas that had been mentioned over the preceding three days and to identify potential future opportunities for both the United States and Russia on the conversion of research reactors from HEU to LEU fuel. During this discussion, many key points were brought up by individuals in attendance at the symposium. These points include the following:

• Many symposium participants from both the United States and Russia emphasized the importance of reducing and, where possible, elimi­nating the use of HEU in research reactor fuel. Over the past few decades, the trend in research reactor development—as well as in civilian applica­tions as a whole—has been to reduce the use of HEU.

• Research reactors currently serve important purposes for research and industry, and they will to continue to serve important purposes into the future. In some cases, accelerators or other sources of neutrons could be used to replace research reactors for medical isotope production and other applications. However, for scientific research, some types of irradiation phenomena, and advanced fuel cycle work, research reactors will continue to be invaluable into the foreseeable future. Several workshop participants stated that these reactors must continue to operate safely and cost effec­tively and fulfill their missions in ways that meet the needs of customers.

• Collaboration between the United States and Russia on conver­sion of research reactors will continue to be essential and fruitful. Daniel Wachs observed that past collaborative U. S.-Russian work on fuel develop­ment has provided opportunities to advance conversion of both countries’ reactors; he stated that the cross-fertilization of ideas, lessons learned, and technological advances has been helpful and should continue to be encour­aged. In addition to technical collaboration, one participant observed that there is significant potential for collaboration on the regulatory aspects of conversion as well. Alexander Adams and V. Bezzubtev noted that Russia will face many challenges in regulating its to-be-converted reactors; the United States has previously faced many similar challenges and may have helpful advice for Russia on this issue.

• The United States and other nations have been able to convert re­search reactors to LEU fuel while maintaining performance required for key missions, e. g., research as well as medical and industrial applications. H.-J. Roegler observed that prior to conversion of many research reactors in Eu­rope there were a number of concerns about maintaining needed functional­ity after conversion. However, in the end, the performance of many research reactors was improved as a result of the conversion process through design changes and better understanding of reactor behavior. P. Adelfang added that an analogy might be made to molybdenum-99 production. In 2001, Argentina’s Comision Nacional de Energia Atomica (CNEA) made the deci­sion to convert its domestic production from HEU targets to LEU targets. At that time, it was considered to be infeasible to produce molybdenum-99 in significant quantities using LEU; however, CNEA showed that it could be done. After nine years it has become abundantly clear that high-quality molybdenum-99 production is possible with LEU targets.

• The economic and performance challenges associated with conver­sion are likely to be surmountable, particularly with government assistance and the involvement of reactor operators and customers. Research reactor conversions have been successfully completed in many countries, but many of these efforts would have been unlikely to occur without U. S. government support. B. Myasoedov and Jeffrey Chamberlin agreed that government in­volvement is critical to future conversion successes in Russia and the United States. Jordi Roglans noted that governments’ decisions regarding future HEU use would likely be influenced by the potential for economic and other upheavals if a terrorist event involving HEU occurred related to research reactors or otherwise.

• Some facilities may not be easily convertible to LEU fuel, includ­ing fast reactors, fast critical assemblies, reactors with small core volumes, and reactors with high specific power per unit volume of active core. The

feasibility of conversion depends to some extent on policy choices by the host nation’s government. Several workshop participants suggested that one way of minimizing the use of HEU for essential or unique missions would be to create major international nuclear centers to house the few reactors needed for these missions and to ensure that those facilities have strong se­curity and safeguards protection. A. Zrodnikov observed that international centers would complement conversion, because a large international facility would allow research to be done that would be more challenging than at a smaller facility. In addition, he observed that at such facilities it would be easier to manage high-quality MPC&A as well as physical protection because of the international attention that such facilities would receive, especially if such facilities were placed in nations with well-developed nu­clear infrastructures. The suggestion regarding major international centers received support from several Russian participants.