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6 Modernization of the Complex Most of the physical plant of the nuclear weapons complex is, in a word, old; many of the processes employed, generally dating from the 1940s and 1950s, are old-fashioned. Consequently, opportunities and challengesexist not only for refurbishing the plant but also for introducing alternative processes that could improve overall efficiency and facilitate the attainment of health, safety, environmental, and production goals. In this chapter, we review selected modernization issues and describe some technological opportunities for improving current and future operations, including remediation of existing waste sites. We recognize, however, that modernization explants and methods costs money. Decisions to decommission existing buildings, to build new production facilities, to rebuild existing ones or to take advantage of new technologies must take account of the benefits to be gained for the costs incurred, including opportunity costs. THE DOE MODERNIZATION REPORT At the request of Congress, DOE (1988) prepared a report on the modernization of the complex, projecting its configuration to the year 2010. Congress asked that the study consider '`. . . the overall size, productive capacity, technology base, and investment strategy necessary to support long-term national security objectives." The DOE study emphasizes that the mission of the complex is to supply the DOD stockpile requirements and, at the same time, to maintain technological superiority and comply with health, safety, and environmental requirements. The Department 81
82 THE NUCLEAR WEAPONS COMPLEX also considers flexibility in the production capability of the complex to be another important requirement. The Department's report, while not necessarily adopted as guidance by the current administration, is the only available planning document with a long-term focus. The report recommends changes for the complex in three categories, in order of phony (see Figure 6.1~. The first category includes acii`'iDes considered essential that must be accomplished in the near term. In this category are remediation of existing inactive waste sites, as well as compliance with applicable regulations at currently active waste disposal sites, refurbishment of plutonium recovery capacity in Building 371 at the Rocky Flats Plant, construction of new production reactors and processing facilities at the SRS and INEL, and construction of an SIS facility at DUEL for the enrichment of fuel-grade plutonium into weapons-grade plutonium. The second category~eemed essential but not urgent includes upgrading facilities for processing virgin plutonium at SRS; upgrading the Y-12 Plant facilities for processing uraniums; upgrading, renovating, and modernizing facilities and laboratories throughout the complex; and establishing facilities at SRS, INEL, and the Hanford Nuclear Reservation for vitrifying mixed hazardous and radioactive wastes for eventual permanent storage. The third priority includes objectives considered optimal for the future, although their phasing would have to depend on the availability of funds. This category includes permanently closing the Feed Materials Production Center (FMPC) at Fernald; eliminating the weapons programs at Hanford; relocating the activities currently performed at Rocky Flats; and relocating the materials operations at the Mound Facility. Without specifically commenting on each of the proposed changes in the renovation and modernization report, we focus on two broad issues: the capacity for processing plutonium and the need for maintenance. Capacity for Processing Plutonium Most of the activities of the complex focus on the production, separation, and preparation of plutonium and tritium. Obviously, the expected future demand for the production of these materials thus must be evaluated in order to guide the modernization of the complex. Indeed, because the projection of demand provides the foundation for long-term planning, it is important that DOE and the Congress obtain the best and most objective advice that is available on this point. We have no special information or expertise that enables us to assess the content or future requirements that are or might be imposed by the President's Stockpile Memorandum. Nonetheless, some general observations can be made. Given a level of demand for new or refurbished weapons, the production capacity for tritium is the more problematic because tritium is a highly perishable isotope (i.e., it has a short half-life, 12.3 years). The situation is different regarding
MODERNIZATION OF THE COMPlEX Note: Lines indicate ti TO from Project start to completion Priority 1 Time Critical & Essential: Environmental, Satety and Health Corrective Action Upgrade Plutonium Recovery (Rocky Flats) New Production Reactor Capability Special Isotope Separation for Weapon-Grade Plutonium Priority 2 Essential: Upgrade Virgin Plutonium Infrastructure at Savannah River Upgrade Uranium Facilities at Y-12 Nuclear Weapons Production Complex - Existing Plant Modernization Nuclear Materials Production Complex - Upgrade and Renovate Facilities Research, Development and Testing Complex - Modernization Vitrification Facilities for Waste Packaging: Savannah Hanford · Idaho National Engineering Laboratory Priority 3 Optimal Funding for the Future: (Phasing Dependent on Funding) Close Out Feed Materials Production Center (Fernald) Phase Out Weapons Programs at Hanford Relocate Activities of Rocky Flats Plant Relocate Mound Nuclear Materials Operations HWR - Heavy-Water Reactor HTGR - High- Temperature Gas Cooled Reactor 83 199: ·,~ ~:0 :~ ~, ~ Ongoing Ongoing Ongoing OR ~ odub ~ n~ob'ed To Common FIGURE 6.1 Priority and schedule of key moderTiizaiion actions.
84 THE NUCI~:AR WEAPONS COMPLEX plutonium; its current supply in the stockpile of weapons, scrap, and spent reactor fuel is large and its half-life is very long, about 24,000 years. Conclusion The current supply of plutonium and the current capacity to process both virgin and recycled plutonium from retired weapons or scrap are adequate to meet the dernandfor maintaining a stockpile sinular to the current one. The national stockpile currently contains several tens of thousands of nuclear weapons. The plutonium in these devices, plus that in the supply chain, is obviously sufficient to supply a nuclear deterrent of the existing size or even greater. Because plutonium is long-lived and toxic and must be carefully safeguarded for reasons of national security, the production of additional, virgin plutonium implies additional costs to society for maintaining safeguards and protecting public health and the environment. These costs must be borne for an indefinite time, and hence, other things being equal, it is not sensible to produce more plutonium than we need. The Department plans to obtain additional capacity to process weapons-grade plutonium by using both chemical and isotope separation methods to recover it from scrap and recycled weapons and by laser isotope separation of reactor-grade plutonium produced in the N-Reactor at Hanford (see Appendix B). The Department proposes to add to its capacity to process plutonium scrap by renovating Building 371 at Rocky Flats at an estimated cost of $400 million. Serious questions exist about the cost-effectiveness of this renovation if DOE concludes, as the modernization report urges, that all operations now at Rocky Flats should be moved elsewhere. Moreover, the need for additional scrap recovery capacity is doubtful. The $90 million New Special Recovery (NSR) facility, also designed for plutonium scrap processing, is already in an advanced stage of construction at SRS. And the Plutonium Facility (Building TA-55) at LANL is an efficient and productive operation for scrap recovery. This facility, operating for the most part on a one-shift, 5^y schedule, can process almost half as much plutonium as Rocky Flats can (even if Building 371 were to be renovated) and turn out a purer product. If additional capacity beyond NSR is desired, institution of a three- or four-shift operation at the LANL facility should be more than adequate to handle the complex's plutonium recycling needs. Although there may be resistance at LANL to converting Building TA-55 into a full-scale production facility, an administrative solution should be possible. In any case, more extensive use could be made of this efficient operation with its exemplary operating history and its strong technical staff. The development of isotope separation technology is approaching the pilot plant stage at LLNL. DOE proposes to construct a production-scale SIS facility at INEL at an estimated cost of $600 million. Plutonium containing concentrations of plutonium-240 greater than 7 percent is undesirable for use in weapons (see Appendix E). Plutonium containing more than 7 percent but less Han 13 percent
MODERNIZATION OF THE COMPI=X 85 plutonium-240 can be converted to weapons-grade material by blending it with plutonium containing much smaller concentrations of plutonium-240 obtained from Savannah River. Thus SIS would be used to process plutonium having more than 13 percent plutonium-240 to obtain purer material to be used in blending. The weapons complex inventory of reactor-grade plutonium containing more than 13 percent plutonium-240 is located at Hanford and amounts to about 7 or 8 tonnes. But, to our knowledge, no compelling need for this material has been demonstrated, nor are there currently forseen uses for the SIS facility after the reactor-grade plutonium has been processed. Special isotope separation also introduces important new considerations relating to safety and safeguards. First, SIS is the first process that involves the vaporization of plutonium in a high-vacuum system. We have no reason to believe that this process will create a major new hazard that cannot be managed; but the new technology raises environmental controversies, and considerable effort is required to demonstrate that concerns about human health and the environment can be satisfied. Second, SIS introduces a potentially undesirable precedent with respect to nonproliferation goals (NAS 1985~. By introducing technology for converting reactor-grade to weapons-grade plutonium, it forms a potential bridge between the civilian fuel cycle and weapons production. Spent civilian power reactor fuel contains substantial quantities of plutonium, but this fuel contains concentrations of plutonium-240 sufficiently high that, in the absence of SIS, it would be undesirable for use in weapons. Federal law prohibits the use of spent civilian reactor fuel for nuclear explosive purposes (42 U.S.C. 2077~. Once developed, the SIS technology could be applied in other countnes, including those not now possessing such weapons, greatly increasing the quantity and improving the quality of materials from which nuclear weapons could be built (NAS 1985~. Any decision to proceed with the SIS facility should explicitly consider the implications of the technology for nuclear proliferation. Recommendation The Department of Energy should concentrate on malting better use of the existing plutonium processing capacity as required and postpone plans to construct additional capabilities. Renovation and Modernization The Deparanent's modernization report calls for an annual outlay of 4 percent of the replacement value of the physical plant per year for renovation and modernization. The allocation is evidently based on a rule of thumb that is applied in industry to estimate maintenance expenses. Without clearer understanding of how the renovation and modernization activities envisioned in the report relate to maintenance, we find it difficult to comment on the adequacy or the basis of this allocation. As discussed in Chapter 2, we found the level of attention paid ~ maintenance
86 T~ENUCl~AR WEAPONS COMPLEX in the past to have Men generally inadequate, and we support the improvement of efforts in this area. We also noted that, given the special nature of the complex, common rules of thumb may not apply. Determining the level of funding needed for maintenance and the allocation of resources for the purpose varies wad circumstances and should be determined as the result of the usual budgeting process. Although increased maintenance does impose costs, the benefits can include greater safer, as well as improved reliability and availability of equipment OPPORTUNITIES FOR ADVANCED TECHNOLOGY The Department's 5-year plan for environmental remedial action and waste minimization includes a research and development program that is aimed at the demonstration of new technology for these purposes. We strongly concur with the emphasis in this plan on the need for advanced technology in waste management and remediation, and we agree that the research and development necessary to achieve it is vitally important The Department and its contractors should also be alert to opportunities from other sources to introduce new technology or to employ more benign materials, thereby improving the effectiveness of the complex in meeting production goals in a way that is consistent with health, safety, and environmental objectives. Over the past decade or two, private industry has increasingly recognized the importance of using technology that meets these multiple objectives, particularly in minimizing the generation of wastes. Developing or taking advantage of advanced technology is an essential ingredient in the success of private industry, and it can be no less valuable in improving the efficiency of the complex. For example, the complex generally employs costly, old-fashioned metal- forming processes typical of foundries and machine shops, perhaps because these were the only processes available when the complex was originally designed. Unfortunately, foundry and machine-shop processes typically create significant quantities of scrap and substantial problems of waste management. Indeed, a substantial portion of DOE's processing efforts is dedicated to recycling the scrap materials generated in these processes. Moreover, the scrap and waste problems are exacerbated in the case of weapons production by requirements for safeguards and by the hazards of radioactive and toxic materials. Perhaps alternative processes exist that could increase both efficiency and safety in the use of special nuclear materials and, at the same time, minimize problems of maintaining safeguards and managing waste. Perhaps significant long-term savings might in fact be realized by using more modern and efficient processing technologies. We have not made a comprehensive survey of the technology opportunities that are available to the complex. That task is a daunting one, particularly if undertaken from the outside and from the top down. In the course of our review, however, we considered several particularly important opportunities that can serve as examples.
l~ODERNIZATlON OF THE COMPl=X Upgrading the Chemical Processing of Plutonium 87 Conclusion When the weapons complex was originally designed, chemical processes for the separation of plutonium were based on fluoride cherrustry. These processes create substaniial problems of toxicity, corrosion of equipment, and exposure of workers to radiation hazards. Safer alternative processes are now available. Historically, the conversion of plutonium solutions to metal has involved a multistep process based on fluoride chemistry (see Appendix D). The process, which is based on extractive metallurgical procedures in use for many years, has been used to recover plutonium since the days of the Manhattan Project in World War II. It has the advantages of reliability and relative ease of operation. Unfortunately, it also has disadvantages. Gaseous hydrogen fluoride and aqueous hydrofluoric acid are exceptionally corrosive. Both are also highly toxic and have properties that exacerbate the problem: hydrogen fluoride, being a gas, is readily mobile, and hydrofluoric acid has the ability to penetrate the skin, causing systemic poisoning. Moreover, plutonium fluorides emit copious neurons from alpha-e reactions approximately 200 times as much as is emitted from plutonium oxides. Neutron exposure can be reduced by shielding enclosures and equipment, but effective shielding often impedes operations because of its clumsiness. It is better to remove the source of radiation than to try to shield against it. Viable alternatives to fluoride-based plutonium processing exist Frequently, for example, plutonium in recycled weapons can be subjected to molten-salt extraction to remove americium (the main contaminant of concern) and then refabricated for reuse. Less pure plutonium requires more extensive chemical processing, but the fluorination step can be bypassed by direct oxide reduction (DOR), in which plutonium oxide (PuO2) is reduced directly to metal with calcium. Yields from DOR are lower than those from plutonium fluoride (PuF4) reduction (but in either case the sludge must be reprocessed), and the product may require electrorefining to achieve the desired purity. The reduced yields, however, may be offset by the lower costs associated with reduced herds and lower maintenance requirements so that the net result may be a the lower total cost per unit of plutonium produced. Even if not all the steps in its multistep production are replaced, the total use of fluoride processing can be reduced. Specifically, replacement of the fluonnanon steps in existing peroxide and oxalate precipitation-based processes appears to offer net advantages. Such a drastic process modification would take time and money to introduce at some facilities in the complex, and alternative processes may require additional development effort before they can be made suitable for full-scale application to production. Nevertheless, there is little doubt that these processes can become
88 TIlENUCl~AR WEAPONS COMPLEX effective replacements for the existing fluonde-based technology. The capability already exists at LANL. Recommendation As it proceeds in its modernization Forts, DOE should give priority to replacing any needed capacity for plutonium conversion processing that currently is based on fluoride chemistry with technology based on safer, less corrosive materials that may offer lower total costs when proper maintenance, health, safety, and environmentalfactors are taken into account. Computing and Communications Technology Conclusion The Department ~ Energy nuclear weapons complex can make better use of computing and communication technologies to improve performance, particularly in operational areas like training, safety, process control, and management. Within the weapons complex, computing and communication technologies are actively used in a diversity of applications, although such use is inconsistent and less than optimal when viewed across the complex as a whole. Some of the best expertise in scientific computing in the world resides in the laboratones. Notable examples of success imported from outside sources exist at the facilities in obvious areas such as accounting, management, inventory control, and documentation. Successes are less visible in operational areas such as process control, training, and event or status logging. The potential for application of computer technology spans virtually all aspects and levels of operations across the complex and constitutes an opportunity for significant, sustained improvement in performance and safety. The world's base of computing technology continues to grow, driven by advances in very large scale integration, data storage and systems, and most significantly, accessible computers, networking, and application software. While the DOE laboratories are among the leaders in scientific computing, which they pioneered for studies in such areas as reaction physics, thermomechanical behavior, and scientific data analysis, the production facilities lag behind the state of the art in applying computing tools to field operations. Opportunities for broad exploitation include the following. · Simulators for training operators. Training resources and techniques vary widely across the complex: most of the installations rely on classroom training and operations manuals. At SRS, training of chemical process operators, as well as reactor operators, incorporates computers, simulators, and full-scale replicas. These advanced techniques are extremely effective in giving operators detailed
MODERNIZAT70N OF THE COMPLY 89 understanding of processes and operations and should be adopted across the complex. · Operational monitoring of tank transfers. The use of computers has significantly reduced errors that occur in this common operation at some facilities, but the use is not widespread in the complex. · Event logging. Records ranging from shift activities to logging of field status reports are now prepared mechanically for the most part. Such logging could be extensively computerized with obvious benefits for identifying outliers immediately, reconstructing events, establishing trends, and other tasks. · Schedules and planning. Using- computers to optimize factory processing would allow flexibility in production practices in a modernized complex. The Y- 12 Plant has apparently been applying computers for such tasks successfully. · Medical data. Collection of data on the health of workers and records of exposure using automated data systems that are available commercially would facilitate data access and analysis. Some groups within the complex have in fact been developing software applications to improve the performance of the weapons complex, and we envision that computing will inevitably play an ever more critical role in its safe and environmentally sound operation. Recommendation The Deparonent of Energy should encourage and facilitate computer use as it Affects operations, health, safety, and the environment throughout the complex. The Department should promote local aru' complexwide networking to archive and disseminate successful practices. Specifically, DOE should develop and apply computing technologies of critical and specific relevance to the weapons complex, such as training simulators, process controllers, and event loggers. Robotics Conclusion The Department of Energy can make better use of robotics and remote technology in perforrrung the work of the weapons complex. Robots refer here to electronically controlled mechanisms that perform useful work. The weapons complex has special needs for robotic devices of many types. They include mobile work systems of the kind used at Chernobyl and Three Mile Island, stationary devices that service hot cells and package waste, automated excavators that can exhume buried waste, matenal-handling robots for repositories, and automated machining and processing robots of the kind appropriate for the modernized complex of the year 2010. The application of robots within the complex should depend on the nature of the task, risk, robotic competence, and cost. While the most universal motivation
go THE NUCI~AR WEAPONS COMPLEX behind the use of robots is the escalating cost of manual operations, another impetus is the effort to cope with conditions that are threatening to humans, such as acute exposure to radiation during emergencies, exposure to contamination in waste-handling operations, and activities in constricted work spaces. In such circumstances, robots can have great advantages over manual alternatives. Robots are also obviously useful for repetitive tasks that demand high precision but that workers may find boring. The application of robotics or even an awareness of the robotics state of the art varies significantly throughout DOE. Most of the sins have at least fledgling programs in robotics or experience with components that could become the building blocks for more complicated applications. But overall, the weapons complex has generally not taken advantage of more recent advances in robotics. Although the earliest remote manipulators were pioneered for nuclear hot-cell work, subsequent technological evolution was driven more by advances in subsea activities and by missions of the military, the manufacturing community, and most recently, the space program. Numerous opportunities exist now for applying robotics throughout the complex, but certain targets emerge at specific sites. Of course, successful demonstrations anywhere can always be made more broadly applicable. Examples of opportunities include the following. · Emergency response. To our knowledge, the complex does not have a viable fast-response force with expertise, devices, personnel, and transportation at the ready in the event of emergencies that limit human response. The responses at Three Mile Island and Chernobyl were hampered by just such a lack of remote equipment, and they focused the world's attention on the need for it. · Buried tanks (single- and double-walled). Aged, faulty, and contaminated tanks are a generic problem throughout the complex. Robots could play a significant role here in inspection, remedial action, and as necessary, decommissioning. Constricted spaces like the annulus of double-walled tanks also preclude human entry and call for the use of robots. · Excavation. Buried wastes, such as those in trenches at the Y-12 Plant, are candidates for unmanned excavation, but the most visible, voluminous, and imminent application is the exhumation of acres of transuranic and mixed wastes at INEL. Robotics is clearly the technology of choice in such applications. Other opportunities include inspection; characterization and cleanup of ductwork; subsurface mapping, particularly prior to excavation; maintenance of hot cells and repositories without human entry; facility decontamination and decommissioning; and unmanned production processing. Robotics has the potential to reduce costs and risks significantly, but cost projections must be examined with care: the use of robots involves large front investments in engineering and equipment Opportunities may exist for DOE to
MODERNIZATION OF THE COMPLEX 91 incorporate existing robotic capabilities developed for other applications, but in certain cases, the conditions under which robots might work in the complex may place special requirements on the systems. Examples affecting design include the need for radiation-tolerant components and consideration of decontamination for · ~ servicing or replacement. Recommendation The Department of Energy should expand its use of robotics technologies wherever they can be applied to fulfilling the critical and specific needs of the mission of the weapons complex cost electively.
