NEDHO - Members

Nuclear Engineering In Transition: A Vision for the 21st Century

J. Feidberg and M. Kazimi (Editors)
G.Emmert, W. Kastenberg, J. Poston, V. Ransome, J.Tulenko, G. Was and D. Woodall

December 1, 1998

A publication by the Nuclear Engineering Department Heads Organization

Warning: The web version of this document is under construction.

This report describes the current status and future directions of hte nuclear engineering profession in the United States as viewed by the nuclear academic community. It surveys the contributions of nuclear engineering to enhancing the well being of society, now and in the futrue, and the steps that the university community and the U.S. government can take to ensure that our national needs are met. The report also presents several recommendations to the government and academia for proceeding to implement these steps in the future.

The main conclusion of this report is that the nuclear engineering profession is essential to the well being of the country since it brings great benefits to society in terms of energy security, national defense, medical health, and industrial competitiveness. We further recognize that the nuclear engineering profession is in a period of transition from one encompassing a much broader range of applications of nuclear science and radiation technologies. The country has a persistent demand for nuclear engineers that will almost certainly increase in the future, notably in non-traditional areas of nuclear engineering.

In contrast, data from the U.S. Department of Energy indicates that the number of new nuclear engineers being educated in our academic institutions is diminishing. This apparently contradictory state of affairs is largely due to the uncertainty about the future of nuclear power technology in the United States. The lack of new plant orders for the past twenty years, coupled with the lack of governmental support for future technology research and development, has let to a reduction in interest in nuclear engineering as a career path among the university student population. Hence, universities are educating fewer students today than they were ten years ago, in spite of the fact that there is a growing demand for such skills.

There are a number of important steps that the university and the federal government can take to correct the situation. Some of the steps are quite bold. They involve a major rethinking of nuclear engineering education, recognition of the rapidly growing area of bionuclear research, and a determination to reevaluate and reinvigorate the role of nuclear power. The main recommendations are summarized as follows:

• The university community needs to make a major cultural shift in its thinking about nuclear engineering education. In essence it has to make a transition from a curriculum dominated by a single technology, nuclear power, to a unified curriculum characterized by a common educational core from which flows a multitude of diverse applications. This core is to be centered on applied nuclear sciences and encompasses low energy nuclear physics, the interaction of ionizing radiation with matter, and plasma science and technology.

• The government should reinvigorate the research and development effort in nuclear energy. In order to truly advance the science and engineering of nuclear energy a new flagship experimental facility, or perhaps a set of several intermediate size facilities, is recommended, presumably built at one or several of our national laboratories. Its The mission should focus on advanced approaches to achieving nuclear energy with maximal safety, minimum proliferation, and minimum waste disposal problems. The specific detailed mission and corresponding device or devices should be determined through a national debate during the coming year involving DOE, universities, and industry, with DOE taking the lead as organizer and facilitator. This new program should be viewed as an investment in our national energy security and national and global environmental quality. Nuclear energy, which already supplies 20% of our electricity today, is the only technology available to economically supply vast amounts of energy should affordable gas and oil fuel supplies be disrupted due to unforeseen world events or the environmental problems resulting from the burning of fossil fuels, particularly as those associated with greenhouse gasses become more critical.

• In order to satisfy increasing societal demands for nuclear engineers with training in radiation science and technology it is recommended that the DOE establish a separately designated, clearly distinguished, program for bionuclear and radiological research similar to basic energy sciences or high energy physics. Bionuclear technology and radiological engineering are applications of nuclear engineering of particular importance to the medical health of the country. Currently, governmental funding of such research is dispersed in many small segments over many different programs.

This report describes the current status of the nuclear engineering profession in the United States as perceived by the nuclear academic community. Its purpose is to describe the importance of nuclear engineers to the well being of society now and in the future, and the roles that the university community and the U.S. government can play to insure that our national needs are met. The report also presents several constructive recommendations for proceeding into the future.

In brief, those of us in academia have come to recognize that the nuclear engineering profession is in a period of transition, from one focusing primarily on nuclear power to one encompassing a much broader range of applications. A compelling case is made in the report that a strong nuclear engineering community is necessary for the well being of the country in terms of energy security, national defense, medical health, and industrial competitiveness. The case is made by presenting a description of a broad range of nuclear applications, many of which are known by some but, we suspect, all of which are known by few. The conclusion is that the country has a strong need for nuclear engineers that will almost certainly grow in the future.

In contrast, an equally compelling case is made that the number of new nuclear engineers being trained educated in our academic institutions is diminishing. This data comes directly from the U.S. Department of Energy (DOE) studies. The trends are quite obvious.

It is worth stating that this apparent contradictory state of affairs is largely due to the uncertainty in demand for new nuclear power technology in the United States. The lack of new plant orders for the past twenty years, coupled with the lack of governmental support for future technology development, has led to a reduction in interest in nuclear engineering as a career path among the university student population. Hence, universities are educating fewer students today than they were ten years ago in spite of the fact that there is a growing demand for such skills.

It would be a mistake, a serious mistake, not to correct this problem. Quite bluntly, for the well being of the country, nuclear engineering applications are just too important and just too plentiful to ignore. Even so, the nuclear engineering community cannot simply claim immunity and sit back and wait for nuclear power to be rejuvenated.

There are a number of important steps that the university community and the federal government can take to correct the situation. These are described in the recommendation section at the end of the report. Some of the steps are quite bold. They involve a major rethinking of the nuclear engineering educational disciplinary focus, recognition of the rapidly growing area of bionuclear technology, and a determination to reevaluate and to reinvigorate the role of nuclear power in society.

The link between energy availability and quality of life in our society, even though undisputed, is only casually considered by the public and the policy makers. Nowhere is this link more evident than in the U.S. which accounts for 25% of the world economy and 25% of the world energy consumption. Our Gross Domestic Product (GDP), productivity, and quality of life have all grown steadily during the past century and so has our energy consumption. Similar trends are true of the rest of the world that generally admires our standard of living. The quest for prosperity will continue to increase demand for energy all over the world. A second factor that will cause growth in energy needs is population growth. The world population grew in this century from about 1 billion to nearly 6 billion people. During this same period energy use has grown by a factor of 11, about double the rate of population growth.

The societal changes that have taken place in the U.S. and the world during this century have been fueled by an energy cycle that was initially based on biomass at the turn of the century but has transitioned to be based on fossil fuels at present. The current U.S. energy sources are 80% fossil fuel, 10% nuclear, 5% hydro, 4% biomass, and 1% other renewables, primarily geothermal, and wind. The largest fossil fuel source is coal but most new electrical capacity needs are being met with natural gas. However, this process cannot continue ad infinitum for two reasons: first, the finite nature of the fossil fuel source and second, the effect of continued burning of fossil fuels on the atmosphere. A sustainable society must plan for the eventual transition to non-fossil energy sources that are more plentiful and environmentally more attractive.

Nuclear power is the second largest energy source, after fossil fuels, at present. Given the considerable difficulties that must be overcome in order to achieve economically competitive renewable energy sources, it is important that U.S. energy policy pursue a more aggressive effort to exploit nuclear energy options that are more widely acceptable in society. In this regard the Japanese energy R&D budget is in stark contrast to the U.S. energy R&D budget. Japan is focusing on nuclear energy while the U.S. is focusing on efficiency, renewables, and fossil fuels. In December of 1997 the committee of scientific advisors to the president (known as PCAST) recognized nuclear energy as a source of value for production of electricity that emits no greenhouse gases. However, PCAST recommended much less funding for it than all other sources of energy. Yet, if we are to take global warming and political vulnerability of energy supplies seriously, no energy source is as ready for wider use than nuclear energy.

Therefore, it is important to investigate how to extend the life of the existing nuclear power plants if they are to remain economically competitive. This involves an effort to determine the lifetime of the critical components and to extend that lifetime if necessary. It may also involve the use of improved information technology for monitoring and improving plant performance in the extended life.

It is equally important to vigorously investigate technology options for future plant designs that can provide the U.S. with a desirable economic source of nuclear energy in the next century. Plants with natural safety, reduced waste burden, reduced proliferation potential, improved thermal efficiency, reduced capital cost, reduced construction time, and more automated control, maintenance and inspections will be needed. The government should directly invest in advanced nuclear technology as a major research and development program and, at an appropriate future time, provide an economic incentive to nuclear energy providers. This will help ensure the availability of nuclear energy as a non-greenhouse gas-emitting source of energy.

It is occasionally perceived that civilian nuclear power technology is coupled with nuclear weapons technology. Since the Carter administration, there has been a de facto moratorium on the development of the nuclear fuel cycle technology in the United States. In contrast, European and Japanese programs continued their search for a fuel cycle that recovers the fissionable materials from spent nuclear fuel and disposes of the fission products from the fuel as waste. Recent testing of nuclear weapons by India and Pakistan has demonstrated the impotence of this nonproliferation strategy of the U.S. Not only has this policy been unsuccessful, it has led to a degradation of nuclear engineering capability in the United States. Rather than pursuing a fuel cycle that has stronger nonproliferation attributes, research on nuclear fuel technology was completely stopped and the production of new graduates in the area of nuclear fuel cycle essentially nonexistent for almost twenty years. The U.S. has retreated from the leadership role that it once held in the field of nuclear engineering. Instead of pursuing new and novel ideas that could provide the breakthroughs of the future, the U.S. has taken a negative approach in which economic sanctions have been used to pressure non-nuclear countries to refrain from development of a nuclear capability including nuclear power. Not only has this policy not worked, it has also discouraged development of new nuclear technology in the United States. Even very promising research on advanced fuel cycles has been curtailed or terminated at the national laboratories and the universities.

There are several opportunities to improve the fuel cycle either by demanding a waste minimizing approach to the once-through fuel cycle or by allowing recycling in a non-proliferating technology.

The idea of using the fusion reaction to produce commercial electricity was conceived over four decades ago. The promises then, as now, remain spectacular: unlimited fuel easily accessible to all and power plants that are virtually pollution free with very low radioactivity. In short, commercially produced fusion power would have an enormous impact on the world's energy supply.

As we now know, the problems involved in achieving this dream have proven to be extraordinarily more difficult than originally imagined. Even so, remarkable progress has been made. On the scientific frontier fusion grade plasmas have been produced in the laboratory generating over 10 MW of power for short periods of time. The next generation experimental facility should achieve ignition, the critical situation where a certain fraction of the fusion energy released is sufficient to overcome inherent energy losses in the plasma; that is, the experiment becomes self-sustaining.

In spite of this progress commercial fusion power is still 30-50 years in the future. Additional plasma physics problems and very difficult engineering problems remain. Researchers in the field are confident that these technical problems can be overcome. However, in terms of present day energy costs it is likely that fusion power, as currently envisaged, will be more expensive. This situation could change. Eventual scarcity of fossil fuels and concerns about the environment may make fusion power economically competitive in the future.

Fusion research thus represents a high risk (economically), high payoff endeavor. In terms of our national energy portfolio it makes prudent sense to maintain fusion as a long term insurance policy supported at a steady, appropriately realistic level.

Energy availability is very important to the continued success of the U.S. in terms of economic competitiveness and quality of life. The 21st century will bring the need for great change in the energy sources for the U.S. as well as the rest of the world. We will need to exploit all energy sources to meet these needs. By any rational standard the current U.S. policy toward nuclear energy research and development needs to be reexamined. This energy source is proven, has high potential for improvement, has little impact on the environment (and can be made even cleaner), and can be economically competitive. Nuclear energy, having an indigenous fuel source, provides increased energy security by offering an option to avoid dependence on foreign energy sources. Nuclear technology can also be a basis for new commerce with areas in the world, such as China, that have contributed to a large negative U.S. trade balance in recent years.

In the distant future (the second half of the next century), fission breeders and fusion are the only energy sources on the horizon that can meet the energy needs of the U.S. and the world on a limitless basis. While breeding reactors of many types have been proposed over the years, only sodium-cooled reactors have been investigated and demonstrated. Other coolants may prove to offer operating advantages and should also be investigated. Lead bismuth reactors and gas-cooled reactors have certain advantages. Additionally, we must continue to pursue fusion until technical success is achieved and economic viability assessed.

The U.S. Navy relies heavily on the use of nuclear power in its submarine and aircraft carrier fleets. In particular, the demands on mobile nuclear power plants in navy submarines are high. The Naval Reactor (NR) program operates two key research laboratories whose mission is to provide analysis, design and support technology for the construction, operation and maintenance of the U.S. Navy nuclear fleets. These laboratories are Knolls Atomic Power (KAPL) in Schenectady, New York and Bettis Atomic Power Laboratory in West Mifflin, Pennsylvania. Together they provide capabilities in core design, reactor physics, fuel management, reactor engineering, fuels and materials performance and other supporting technologies. In addition to these two laboratories the DOE operates the Advanced Test Reactor (ATR) at the Idaho National Engineering and Environmental Laboratory (INEEL) which tests the prototype fuels and materials for all naval reactors. These laboratories are critical to the success of the navy nuclear program and have historically drawn on nuclear engineers for the technical expertise to carry out their missions.

The laboratories employ a significant number of nuclear engineers from all of the different subdisciplines indicated above. At the same time the NR program is also continually looking for large reductions in the cost of operations, improvements in the efficiency of fuel, and in increased safety. It is interested in the development of new and novel reactor systems, new fuel cycles, and new power conversion systems. Thus, the success of their mission is highly dependent on a continuous supply of nuclear engineers from the nation's nuclear engineering departments. The skills and technical base that these engineers bring to KAPL and Bettis cannot be replaced by other technical disciplines in either engineering or science. In fact the loss of a supply of nuclear engineers would create much difficulty for the nation's nuclear naval fleet. Because this fleet is a cornerstone of the nation's national security, this is one example where the front lines of national security could be jeopardized without a vibrant and healthy nuclear engineering academic infrastructure in the United States.

Providing security and continued effectiveness for strategic materialsnuclear weapons is often referred to as stockpile stewardship. Additionally, continued security of and is of concern for hundreds of metric tons of strategic materials produced during the cold war is of concern. The most important of these are the relatively long-lived fissile materials; namely, uranium-233, uranium-235, plutonium-249, plutonium-241, and plutonium-242. One aspect of this concern is the disposition of excess weapons plutonium in both the U.S. and in the former Soviet Union, particularly Russia. At the moment the DOE has announced dual track options for plutonium disposition: (1) conversion to Mixed Oxide Fuel (MOX) for use in current light water reactors (LWRs) and (2) vitrification in a ceramic form followed by disposal in a geological repository such as Yucca Mountain. Ultimate decisions regarding these options will be based on both institutional and technical considerations. A broad range of nuclear engineering activities such as reactor core physics, fuel cycle and burn-up analyses, nuclear materials and fuel performance assessments, reactor engineering, and safety assessments are elements of the technical considerations. Institutional considerations will involve strong linkages to social science departments and public policy schools. Russia on the other hand is focusing on the MOX option and is seeking financial aid from a variety of international monetary sources. Nuclear engineering expertise will also be required to assess Russia's plans and activities.

Activities regarding these strategic materials will be long term. Vitrification in ceramic form, as well as MOX fuel fabrication, requires research and development programs. Deployment of MOX fuel will require both regulatory considerations and technical considerations as noted above. Moreover, there will be much public debate and nuclear engineering faculty members and students can play a vital role in informing that dialogue.

Through various international treaties that are now in place, the countries with nuclear weapons are engaged in the process of reducing nuclear stockpiles and dealing with weapons materials that result from their decommissioning. This reduction in weapons inventories will certainly be a positive factor in long term easing of world tensions but presents challenges with regard to the technology needed to monitor stockpile reduction activities. There is also a need for methods to detect nuclear weapons related activities that might be attempted by terrorist groups or rogue states throughout the world. A common requirement is for sensitive radiation detection instrumentation that may also incorporate the ability to image sources from a distance. Future developments in radiation detection instrumentation will certainly contribute in a vital way to this very important national priority.

The subject of arms control and nonproliferation technologies is based on the detection of nuclear material and the characterization of material using nuclear-radiation techniques. The signatures of nuclear weapons are as important to our safety and security today as they were at the dawn of the nuclear age. Research and development in materials science, electronics and computer systems will help to make detection and measurements possible that could not have been made a decade ago. Specifically, improvements are needed in fundamental sensor technology, the heart of any detection system. This includes a search for new scintillation materials and semiconductors suitable for detector applications. For example, there is a need for a scintillator with the excellent light yield of sodium iodide, but incorporating higher atomic number elements to enhance detection efficiency, and also a faster decay time for timing purposes. There is also a need for a semiconductor detector that retains the excellent energy resolution of germanium while permitting room-temperature operation. The requirement of operation at liquid nitrogen temperatures for current devices renders such devices cumbersome and inappropriate for many field applications. Alternatively, the development of compact, low-power electromechanical coolers will allow high-resolution gamma ray detectors to be used in applications where liquid nitrogen is inconvenient.

Beyond these more obvious needs, there are developments that apply completely new principles in radiation measurement. For example, observing the effects of radiation interactions in superconductors has proven to be a fruitful area of research that may well lead to practical radiation detectors in the future. Nevertheless, whether addressing the issue of treaty verification, transparency, law enforcement, nuclear safeguards, or any other aspect of national security involving nuclear materials, the pace of new developments will continue to open new areas of application in the years ahead. The critical element in continuing to make progress is the availability of talented individuals who are educated in the basics of nuclear radiation detection. For without an educated pool of nuclear engineers, progress in this ever-increasingly important field will quickly grind to a halt.

Nuclear engineering has made vast contributions to the advanced medical technology applied daily to improve the human conditions. From production of radioisotopes to advanced imaging techniques and therapy facilities, the role of nuclear engineering in health care has grown steadily in the past decades and will continue to do so in the foreseeable future. Use of Radionuclides in Medicine

The use of radionuclides in medicine has grown into a specialized, well-established field of medicine. However, even today physicians, scientists and engineers in the field of nuclear medicine are constantly striving to improve and advance the technology. Radionuclides are widely used in medical research, diagnosis and therapy, and represent an indispensable part of the nation's health care system. The International Atomic Energy Agency (IAEA) has estimated that between 100 and 300 radiopharmaceuticals are in routine use and most are commercially available. The use of radionuclides in medicine improves the quality of patient care and, in many ways, reduces the cost of health care. Approximately one of every three patients entering a hospital in the U.S. and other industrialized countries will undergo some sort of medical procedure involving the use of radionuclides. It is estimated that just in our country alone more than 13 million diagnostic procedures, 50,000 treatment procedures, and 100 million laboratory tests are conducted annually, all of which take advantage of the unique characteristics of radionuclides. It is difficult to estimate the impact radionuclides have on biomedical research but the use of radionuclides such as 3H (tritium), 14C, 35S and 32P is extensive. Practically every medical center and university involved in biomedical research uses such radionuclides. Radionuclides are used in the development and investigation of new drugs. Essentially every new drug that comes to market has been tested using techniques employing radioactivity as tracers to better understand uptake, metabolism, distribution, and elimination of these materials from the body. Radionuclides are used in many tests as "tracers," i.e., tests in which materials of biological significance are "tagged" with a radioactive substance so that their movement through the body can be followed easily. To understand tracers consider a specific example: the use of a radionuclide in the measurement of blood volume. Actually two measurements must be made, one of the plasma volume and the other of the red cell volume. Iodinated Human Serum Albumin (IHSA) is used to measure the plasma volume. IHSA is available commercially and is obtained by treating albumin extracted from blood with 125I. Estimates of the red cell volume are accomplished by removing some of the patient's blood, labeling the red cells with 51Cr, and reinjecting the blood into the patient. The value of radionuclides in medicine can also be appreciated by understanding the uses of radiopharmaceuticals in the care of cancer patients. A summary of these nuclear medicine procedures includes: (1) detecting an unknown primary site of cancer in a patient found to have metastases, (2) differentiating benign from malignant lesions, (3) grading the degree of malignancy, (4) understanding the extent of the disease, (5) assessing the response to treatment, and (6) detecting recurrent disease. Studies conducted by oncologists, cardiologists, and neurologists using radionuclides include diagnostic evaluations of the brain, heart, lungs, liver, breast, kidneys, and thyroid gland. Patients with bone or joint disorders, along with spinal disorders, benefit directly from the routine use of radionuclides not only for diagnosis but sometimes simply for pain relief. For example, 89Sr recently has been approved for use in the U.S. to alleviate the pain associated with bone cancer.

Common approaches to nuclear tomography include the use of the Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET). Radionuclides used in SPECT procedures are produced in nuclear reactors whereas those used in PET procedures are normally produced in linear accelerators or cyclotrons located at the hospital. Currently, SPECT is more widely used for routine clinical studies because of the availability of radionuclides, less expensive imaging equipment, and lower operational costs. This technique uses a radionuclide that emits a single gamma ray and a rotating gamma camera to produce data on the location of the radionuclide in the patient. The radionuclide 99mTc is widely used in SPECT but other useful radionuclides include 131I, 67Ga, and 210Tl. PET is more suitable for special investigative studies or more detailed diagnoses. This diagnostic technique is based on the coincidence detection of each pair of photons emitted in the annihilation of positrons. These photons are emitted in opposite directions and special detection and imaging devices can be used to produce a cross-sectional image of the distribution of the radionuclide in the patient. PET is the method of choice in many situations due to the high image quality, better quantification, and wider variety of available radionuclides. Radionuclides used in PET include 11C, 13N, 15O, and 18F. All of these radionuclides have short radioactive half-lives (i.e., minutes) and often are produced in the hospital through the use of an accelerator. Another advanced imaging technique is Nuclear Magnetic Resonance (NMR). The application of NMR for medical imaging has grown substantially in recent years. This technique relies on detecting the radiation emitted as atoms respond to magnetic field gradients created in specific ways to influence their spin. Given its ability to identify the density of atomic spins this technique has become the imaging device used for diagnosis in the radiology departments of all large hospitals. In addition it is used in research to identify the particular chemical forms of chemical activities of materials by measuring radiation from the spins of several elements.

The field of nuclear medicine is entering a renaissance period as physicians and scientists are learning how to use all the "tools" available to them for better diagnosis and treatment of disease. Modern diagnostic devices are being combined with advanced treatment techniques to better locate the tumor and deliver doses of radiation directly to the target tissue with minimal impact on healthy tissue. The technology is moving away from massive doses of radiation delivered externally (teletherapy) and has focused on implanting the radioactivity more effectively in the affected tissue (brachytherapy). In addition considerations are now being given to radionuclides emitting less penetrating radiations. A recent example of this is the treatment of arterio-venous malformation (AVM). This condition is a malformation of blood vessels characterized by a mass of unwanted arteries in the brain. A mixture of hydrogel polymer of polyacrylonitrile (PAN) containing a radioactive powder is injected into the artery causing an arterial occlusion, stopping the blood flow into the unwanted vessels. The dose to region must be precisely controlled; otherwise a large lesion could be introduced in the arterial wall causing an internal hemorrhage. Another approach to cancer treatment is called "cell-directed radiation therapy." In this protocol a radionuclide is attached to monoclonal antibodies that are injected into the patient's blood stream. The antibodies seek out and attach themselves to the cancer cells and kill the cells as the radiation energy is delivered directly to the target cells. The use of monoclonal antibodies spares the patient many side effects that accompany conventional external-beam radiation or chemotherapy. Radionuclides used in this application typically are beta-emitters such as iodine-131 and yttrium-90. Radionuclides that emit alpha-radiation are better choices for "cell-directed radiation therapy." Alpha radiation travels a very short distance in tissue and therefore deposits all the radiation energy more effectively in the cancerous cells. The first known clinical trials using an alpha-emitting radionuclide have been conducted successfully at the Memorial Sloan-Kettering Cancer Center in New York. In this study the radionuclide 213Bi was attached to a specially designed antibody for treating leukemia. Initial positive results were reported at the April, 1997 Society of Nuclear Medicine Conference in Seattle, WA.

In another recent development the application of Boron Neutron Capture Therapy (BNCT) using epithermal neutrons for treatment of certain cancers of the brain has entered the stage of clinical trials at Brookhaven National Laboratory and the Massachusetts Institute of Technology. If successful this approach could save the lives of several thousand people in the U.S. who suffer from deep seated tumor growth in their brains.

Contrary to popular belief the irradiation of foodstuffs to disinfect food, delays ripening, inhibit sprouting, and/or extend shelf life is not a new conception. The use of radiation for these purposes has been studied since about 1945. Even though much of the initial interest and early research in this area originated in the U.S., this country has fallen behind the rest of the world in the application of this important technology for the benefit of our citizens. The American Council on Science and Health reports that irradiation is used to treat food in more than 40 countries around the world. These foods include onions, fish, wheat, cereal grains, spices and many other food products. For example, it is estimated that each year Japan treats 15,000 to 20,000 tons of potatoes with radiation to inhibit sprouting and thus reduce spoilage.

The use of radiation to improve food safety has been essentially a neglected technology in the U.S. even though it has been more thoroughly studied than any other food technology. Research conducted over more than 50 years has shown conclusively that there are no adverse health effects from the consumption of irradiated foods. The benefits of food irradiation are obvious. It can eliminate health risks in the food, enhance the quality of fresh produce, improve the economy of food production and distribution, reduce losses during storage and transportation, and disinfect stored products such as grain, beans, dried fruit and dried fish.

There are two types of facilities to irradiate food on a commercial scale: gamma irradiators using a radionuclide such as 60Co or 137Cs or accelerators. Gamma irradiators have the advantage of employing intrinsically natural processes in the irradiator itself. There are few electronic or mechanical parts and the radionuclide supply radiation for the processing whenever it is exposed. The radiation source is usually stored in a water shield when not in use and in the past the solubility of cesium in water was a concern. However, new designs are becoming available to circumvent this problem so cesium is expected to be a major competitor in the future. These irradiators are typically used for bulky items due to the higher penetrating power of the radiation.

Electron beam accelerators can use the direct beam for irradiation. However, the low penetrating power of these beams requires that the foodstuffs be moved through the beam in a relatively thin layer. For example, at 10 MeV the electron beam will provide uniform irradiation only to a depth of about 4 cm. Electron beam irradiation is suitable for products such as wheat or other grains that can be moved through the radiation field in a thin layer on a conveyor belt. A second approach is to use the bremsstrahlung produced by impinging the beam on a target assembly as the radiation source. This allows sufficient penetration to successfully irradiate bulk products. Accelerators have the advantage of being easily controlled allowing easy access to the irradiation chamber.

Regardless of the approach taken technology exists today, with further opportunities for improvement, to allow the construction of irradiators to meet any foreseeable demand. The major issue is creating the demand for safer food products in the minds of a still skeptical public and food infrastructure system.

In the last decade exciting advances have been made in processing materials with radiation. These developments have found their way into numerous material classes including electronic materials, optical materials and structural materials. Both ionizing and non-ionizing radiation have been used but in very different ways. Perhaps the best known example is the use of ion implantation for doping of silicon in the synthesis of integrated circuits. Microprocessors in modern desktop computers are made today using some 13 distinct ion implantations. The outstanding performance of these devices is largely due to the success of ion implantation in achieving the proper dopant profiles but newer applications involve the formation of buried layers and the synthesis of layered structures with well defined phases and interfaces with near atomic-level sharpness. Examples include the formation of buried SiO2 layers in Si which exhibit characteristics that are superior to those of devices formed in bulk Si, and the formation of single crystal, metal silicides such as CoSi2 or NiSi2. Ion implantation has been used to process optical materials where implantation of titanium and nitrogen result in the formation of a buried polycrystalline layer of stoichiometric TiN in amorphous glass. TiN reflects infrared radiation preferentially resulting in a reduction of solar load by over 80% while the transmitted visible light is reduced by only 20%, making it an ideal infrared filter for applications on automobiles or buildings where solar load reduction means significant cost savings in air conditioning. Yet because it is present in the glass as a buried layer rather than a coating or film, durability is dramatically increased.

A more recent development is the synthesis of films and multilayers using a technique called ion beam assisted deposition. This technique involves the deposition of a film simultaneously with bombardment by a directed beam of relatively low energy (1-5 keV) ions. This energy is considerably lower than the 100 keV ions usually used in direct ion implantation. The bombardment with ions during deposition of film material affords control over a number of film properties such as grain size and shape, film density, crystal orientation (texture), residual stress, phase structure, etc. Synthesis of TiN using ion beam deposition results in a hard TiN film similar to films deposited in a conventional manner, but without porosity, providing much better resistance to corrosion of the underlying substrate. Ion bombardment during deposition can be used to control the crystallographic texture of the film which is being used to control mechanical properties, transport properties and solve such problems as hillocking in metallization used in aluminum interconnects in integrated circuits used in flat panel displays. This technique is also being used to create metal-ceramic multilayered or microlaminate materials for use as tough, crack resistant coatings on structural components. Another example is soft x-ray mirrors. In this application, multilayer structures of SiO2/Ni, C/Ni or C/W are fabricated with modulated layer thickness which vary from 1-20 nm and each film consists of hundreds of layers. The optical requirements are such that interface sharpness must approach atomic level dimensions.

Operated in a pulsed mode, lasers have been used for the deposition of films for some time. All PLD techniques have three basic stages: striking a multicomponent target with a laser pulse to create a plasma/vapor plume, the transport of the plume through a vacuum or a background gas and the deposition of the ablated material as a condensate on a suitable substrate where the thin film is nucleated and grown. However, due to the relatively long length of the pulse in typical nanosecond pulselength laser systems, phase separation or preferential ablations often occurs resulting in an undesirable film structure. As a result of the development of the femtosecond pulsed laser, energy can be deposited into a film so quickly that there is no time for such processes to occur. This type of laser provides a maximum peak power of approximately 1 terawatt which, if focused into a 100 nm diameter beam spot, will provide in excess of 1016 watts/cm2 for the ablation plume. Such power densities represent an entirely new regime for the study of thin film fabrication in reactive gases or vacuum environment. It also produces nearly complete ionization of the target material introducing the potential for a new ion source.

These examples represent only a few of the uses of radiation in materials processing. As the need for more specialized materials with unique properties increases, the use of radiation in processing will continue to expand providing new materials and new structures that are unattainable through conventional processing methods.

Nuclear processes and radiation have found extensive application in industry in the past forty years. The attenuation of radiation passing through matter produces a signature of density or thickness. Thus radiation sources have found numerous industrial applications in quality control. The decay of a radionuclide produces radiation with a unique signature providing an ideal process monitor with applications of trace quantities of materials to large-scale processes, including oil and gas pipeline and surface wear of working materials. An application of energetic plasmas to materials processing is growing dramatically because the energetic particles and radiation produced by plasma provides a novel processing environment. More than a quarter of all processing steps used in the production of modern microelectronics materials uses plasmas. Neutrons and x-rays interact differently with the constituents of matter providing a spectrum of information of material properties, including details on components and their microscopic structure.

Previous sections of this report discussed the use of radiation for sterilization of health products and for improving the shelf life of fresh food products. Another important application of radiation sterilization is in the area of sewage sludge irradiation for destruction of harmful pathogens. The production and disposition of sewage sludge is a major environmental problem for the industrialized world. Such sludge can be sterilized by radiation at a fraction of the cost of heat or chemical treatment with none of the potentially harmful by-products of chemical treatment. Sterilized sludge can be used as a beneficial product for fertilization of public parks. An additional application being explored for such irradiators is in agriculture to mitigate insect predation without the harmful side effects of insecticide residue. Systems to use radioisotopes or portable accelerators for irradiation require continued engineering development.

There are numerous applications of radiation from nuclear process in common commercial products. Smoke detectors use alpha sources to produce ionization in a sample of room air. Airport runway lighting systems use radionuclides. Much emergency lighting in industry application uses radionuclides. Many watches use radionuclides for fluorescent watch face figures. All of these applications require manufacturing processes that safely handle radioactive sources as well as the low-level radioactive wastes produced in processes.

Neutron irradiation of samples is now commonly used to detect trace quantities of chemicals in a sample. Neutron Activation Analysis (NAA) has found application in diverse fields such as geology, anthropology, and forensic science. The continued use of these techniques relies on the availability of neutron sources often managed by those engaged in nuclear engineering. For the reasons outlined in the previous paragraph and others, nuclear engineering is an essential discipline for the future success of American industry. It is important that we have engineers trained in the applications of nuclear processes including the interaction of radiation with matter, shielding, chemical and biological effects of radiation, and the measurement of nuclear and radiological phenomena and processes. The following paragraphs expand on these concepts for four of the high impact areas of research and development for nuclear engineering.

Production quality control through applications of radiation typically includes monitoring of product density in a given volume. There are currently extensive applications of this technology in diverse industries. The inclusion of air into an ice cream mix is monitored by the attenuation of radiation for process control. The oil and gas industry uses radioactive tracers for economical determination of leakage. Weld integrity is monitored efficiently by this technique in manufacturing sites throughout the country.

All of these applications require the engineering of radiation systems that can be safely operated by skilled labor without major life safety hazards. Expanded use of such systems can be anticipated providing employment opportunities for nuclear engineers.

Semiconductor manufacturing includes a number of radiation and plasma technologies. This trillion-dollar industry's continued technology development has led to the production of smaller and smaller components requiring the development of new production technologies. Optical laser systems used for imaging component elements have reached a fundamental physical barrier due to wavelength effects. The technology is moving to ultraviolet light sources and soft x-ray sources as a replacement. Many of these technologies are under development by nuclear engineering programs.

Similarly plasma processing steps are replacing chemical processing steps in many microelectronic material manufacturing environments. Plasma technologies have been developed in nuclear engineering programs because of the initial interest in plasma physics for controlled fusion. The diagnostic techniques and plasma production techniques used in fusion research are now finding application in the plasma processing environment of microelectronics. Plasma-surface interactions produce a fundamentally different morphology than gas-surface interactions due to much different energy distribution of the processing gas and different kinetics in the particle-surface interactions.

Modeling of low temperature plasma behavior during interaction with surfaces is an active field of research for nuclear engineering programs. Continued advances in this field will have major impacts on the production of microelectronic devices.

Photons and neutrons interact with fundamentally different components of a material. Photons have a larger interaction probability with the electronic clouds surrounding atoms. Thus, photons tend to interact preferentially with higher atomic weight materials. Neutrons interact with the nucleus; hence the response is determined by characteristic nuclear properties. Neutrons tend to interact preferentially with lower atomic weight atoms. Very low energy neutrons (cold neutrons) have unique character in that they interact with the microstructure of matter providing a unique probe of material structure.

Research into the structure of condensed matter relies on the availability of cold neutron beams from a nuclear reactor. The nuclear and radiological engineering of high brightness, cold neutron beams includes the engineering of high intensity neutron sources, filtering of high energy components and gamma radiation, guiding cold neutrons to a target region and the development of novel spatial monitors of neutron scattering in a target. Detector device and materials are a continuing area of technology development.

The continued development of cold neutron sources and detection systems will have a major impact on the basic understanding of condensed matter. The nuclear and radiological engineering community will continue to provide the core technology needed for this area of endeavor.

High-performance computing is one of the most powerful technology drivers in the foreseeable future. Numerical methods development and applications, a traditional cornerstone of cutting-edge research in nuclear engineering, can play an even more important role in pushing the frontiers of nuclear technologies from radiation transport to materials modeling to complex phenomena simulation. In the context of the preceding challenges and opportunities simulation and modeling emerge as essential components of an enabling technology with its own unique capabilities and as an indispensable partner to many experiments. The highly multidisciplinary nature of the scientific endeavor of simulation provides a nurturing environment for the education and training of a new breed of nuclear engineers and scientists, young men and women who can cross freely disciplinary boundaries to exploit the emerging technologies in a holistic fashion. A particular area of promise is the integrated simulation of multi-scale phenomena from the nuclear reaction scale to the engineering scale of the component/material where the nuclear reaction is taking place.

The U.S. faces the enormous task of cleaning up the legacy of 50 years of nuclear weapons production. The remediation and waste management challenges within the DOE complex require the development of innovative technologies to allow the cleanup to proceed in a safe and economical fashion. The university nuclear engineering departments and programs represent an extremely important resource for the nation to develop both the educated work force and the innovative technologies to carry out the environmental cleanup in a faster, safer and cheaper way. Current methods available for cleaning up the waste are often ineffective or very expensive. Utilizing the innovative technical resources of the nation's nuclear engineering programs achieves the double benefit of funding the development of the future work force while developing innovative cleanup technologies. The Environmental Restoration and Waste Management (EM) part of DOE funds a large research program, almost $400 million. While the largest portion of the contamination of the defense sites are non-nuclear in nature (gasoline, oils, and chemicals), the overall educational and research needs of the nuclear defense program would mandate a larger participation by the nuclear engineering academic community.

The defense cleanup program offers a wide variety of research challenges for nuclear engineering with its need for innovation in safe storage and eventual disposal of low level waste, mixed waste, transuranic waste, and high level waste. The cleanup of uranium enrichment plants, fuel reprocessing plants, buried waste sites, and the need to develop environmentally attractive processes for future use are compelling reasons for EM to utilize the resources of the nuclear engineering community in its research effort.

The single most challenging problem for nuclear power from a political and technology standpoint is the disposal of spent nuclear fuel. The requirement to quantify the level of isolation of the spent fuel for a period of up to 10,000 years has made this a challenging technical problem. For the success of nuclear power it is imperative that the fuel cycle be closed and that an acceptable disposal program for spent fuel be adopted. While the spent fuel quantities are small due to the fact that a 50 million times smaller volume of nuclear fuel compared to fossil fuel is required to produce the same amount of energy, the high initial level of radiation and the long life of some of the radioactive components makes the disposal an emotional and technically challenging problem. This has resulted in stringent isolation standards that are more demanding than any other isolation of hazardous materials that do not decay in time. A risk-based approach to isolation standards might help resolve the current perceptions about nuclear wastes and their isolation requirements.

The federal government has been responsible for the permanent disposal of high level radioactive waste and spent fuel since the beginning of the nuclear power program when all uranium essentially was government controlled. This responsibility was formalized in the Nuclear Waste Policy Act (NWPA) of 1982 that designated the DOE as the government agency to carry out this federal responsibility. All the other nuclear nations are similarly engaged in setting up disposal programs. There is an international consensus that high level radioactive material can be disposed of safely in geological repositories. It is believed that the geological structure, combined with engineered barriers, can be utilized to isolate the spent fuel from human contact. In 1987 the NWPA was amended to focus site characterization on Yucca Mountain in Nevada. Mine tunnels have been constructed which allow access to the eventual spent fuel emplacement area for geological and performance testing. The technical work on the design, analysis and construction of the spent fuel and high level waste storage site is carried out by the DOE Office of Civilian Radioactive Waste Management (DOE-OCRWM). The funding for the office's activities comes from a combination of a one mil per kilowatt hour levy on commercial nuclear power and congressional appropriations to cover the expense of disposing of defense high level wastes. Congress approves all yearly appropriations amounts. Currently Congress and the Clinton administration differ on the need for a prompt solution. In the interim before the construction of the permanent repository there is a strong push by Congress and the utility industry to construct a Monitored Retrieval Storage (MRS) facility to allow DOE to take possession of spent nuclear fuel and safely store it prior to its permanent emplacement in the repository. The construction and operation of a MRS would alleviate the burden of finding space to accommodate the growing spent fuel quantities at each nuclear plant site.

From the examples cited it is apparent that there are many applications beneficial to society requiring the skills and expertise of nuclear engineers. The applications are quite diverse involving energy, national security, medical health, materials research, industrial technology, and waste management. It should be noted that the examples presented are by no means inclusive and that there are many others not described in detail for the sake of brevity. These include space nuclear power, accelerator neutron sources, weapon effects, nuclear intelligence, inertial confinement fusion (ICF), and regulatory review. Nuclear engineers are required for these applications as well.

The overall conclusion of this section is that nuclear engineers make important contributions to the well being of society through a wide variety of applications. The need for such skills is strong today and will likely grow in the future.

The discussion just presented shows, by a series of specific examples, that societal needs for nuclear engineers are strong and growing. In this section it is shown by examination of various data that the number of new nuclear engineers being trained, as well as the number of academic nuclear programs, are decreasing in spite of the growing needs.

Consider first the training of new nuclear engineers. The DOE maintains a yearly record of the number of undergraduate and graduate students enrolled in nuclear engineering programs in the United States. An evaluation of this data shows a clear decreasing trend in the number of new graduates. This is shown in detail in Appendix A. The data shows large decreases in enrollments across the board from the early 90's to the present: undergraduate students reduced by 62%, MS students reduced by 44%, and Ph.D. students reduced by 29 percent.

This reduction in enrollments has put intense pressure on nuclear engineering departments throughout the country. Some have survived reasonably well but a substantial number have been seriously affected by either being asked to merge with a larger department or in certain cases even being abolished. A list of departments recently undergoing such transitions follows.

Georgia Institute of Technology (merged into the Dept. of Mechanical Engineering)

Rensselaer Institute of Technology (merged into the Dept. of Energy and the Environment)

University of California at Los Angeles (program in nuclear engineering eliminated)

University of California at Santa Barbara (program in nuclear engineering eliminated)

University of Massachusetts, Lowell (merged into the Department of Chemical Engineering)

A final point concerning nuclear engineering education concerns university reactors. Since the number of nuclear engineering students is declining, the educational usage of such reactors is also declining. The larger reactors, which can be effective research tools for a variety of experiments, are also facing difficult times. The DOE policy of funding operations only of national laboratory reactors puts university research reactors at a strong disadvantage in competing for research funds. The net result is that virtually all university reactors must be subsidized by academic funding sources, a situation that becomes increasingly difficult to justify in the face of declining enrollments. Some reactors reduce the subsidy through service contracts for industries that need neutron irradiation products. This helps but is usually insufficient to fully cover the deficit. More importantly this is not a satisfactory long-term use of university reactors whose primary mission is to serve as a center for learning and research. Because of these pressures university reactors are being shut down, usually when re-licensing time occurs. Just within the last year the reactors at the Georgia Institute of Technology, the University of Virginia and the University of Illinois have suffered such a fate.

The conclusion is clear. There is a significant imbalance between society's need for new nuclear engineers and the academic community's abilities to educate them. The reason is quite fundamental and is related to the negative student perception of nuclear engineering as a profession upon which to base a career.

The challenge facing the nuclear engineering academic community is to develop a strategy that will attract substantial numbers of new engineering students and train educate them to meet the demands of the country during a period in which interest in nuclear power remains in hibernation during the near future. The solution lies in a reevaluation of the needs of the profession and the foundations of a nuclear engineering education. Such an evaluation leads to a new vision and corresponding strategy to carry nuclear engineering into the future.

To appreciate these new visions consider nuclear engineering from the academic perspective. Note that the basic mission of a nuclear engineering education remains unchanged from its origin. What has changed is the vision to achieve this mission. The mission remains as follows:

1. Educate students in state-of-the-art nuclear engineering and radiation science.

2. Advance the frontiers of nuclear engineering and radiation science knowledge through research.

For the past quarter of a century a nuclear engineering curriculum, at both the undergraduate and graduate levels, has been focused around and dominated by a single technology, nuclear power. This was almost universally true at the undergraduate level. In some graduate programs separate tracks existed, not always in the same department, in three other areas: fusion, radiation science and technology, and energy systems. Each of these tracks was too small to be self-sufficient and almost completely independent of the other tracks. This "designer choice" approach to education worked very well because of the strong student demand for nuclear power which acted as an anchor allowing the smaller tracks to develop separately along widely different paths as new opportunities arose. It is primarily the reduced student interest in nuclear power that has necessitated a large change in the academic vision.

The main thrust of the new vision is to make a transition from a nuclear education curriculum dominated by nuclear power to a unified curriculum characterized by a common educational core from which flows a multitude of diverse applications.

Essentially all successful engineering disciplines have made a similar transition; that is, from a single technology to a core discipline. For example, mechanical engineering was initially founded on the steam engine, electrical engineering on electric power machinery for illumination, and chemical engineering on the petroleum industry. As their industries matured these departments diversified into new areas, building on a common disciplinary core of knowledge. Their diversity is now so great that they cannot any longer be associated with a single industry. It is now time for nuclear engineering, a relatively new engineering discipline, to make the same transition.

To make the transition it is necessary to define the basic core of knowledge that is common to all applications that students and faculty are likely to encounter. This core is defined as Applied Nuclear Science encompassing low energy nuclear physics, the interaction of ionizing radiation with matter, and plasma science and technology.

This vision represents a major cultural shift in the view of nuclear engineering education and the profession. It should allow nuclear engineering departments to remain vital and healthy even if no new nuclear power plants are ordered in the near future. However, when the need for nuclear power is again awakened, as we believe it will be, the academic community and existing programs will be ready to meet the challenge. The recommendation to the nuclear engineering educational community is thus to embrace this new vision at both the undergraduate and graduate levels and reformulate their curricula along the suggested guidelines. Several programs have already initiated such transitions but much more work needs to be carried out in the future.

The U.S. government can play a major role in correcting the problem of increasing societal demand for nuclear engineers versus the decreasing supply of nuclear engineers trained by universities. It is tempting, but not really correct, to recommend that "if only the government would provide more funds to universities" the problems would be solved. The recommendations listed below do call for more funds although most of these are not directed to universities.

Equally, if not more important, is the recommendation that both the executive and legislative branches of the government adopt a more positive public view of the nuclear engineering profession as related to the well being of society. Public statements acknowledging the vital role that nuclear engineering has played, is playing, and will continue to play far into the future, would go a long way towards improving the perception of the profession. Indeed, such statements would acknowledge that nuclear engineering is an intellectually challenging, exciting, worthwhile, and fulfilling career for students to pursue.

Listed below are several specific recommendations that we hope will receive serious consideration by the government.

1. The U.S. government should reinvigorate the national research and development effort in nuclear energy science and technology in order to ensure the energy security of the U.S. in the 21st century, to recapture the leadership in the international nuclear energy technology market, and to attain the environmental goals of reducing the global emissions of carbon dioxide. The FY'99 $19M appropriation for the Nuclear Energy Research Initiative (NERI), which was recently approved in the budget, is a good first step. However, it is much too limited when compared to the PCAST recommendation of $100M. Even if the DOE request attains the level recommended in the 1997 PCAST report this can only be a vehicle for initial exploration of ideas for advanced nuclear power systems and fuel cycles. It would not allow, for instance, the building of any large new facility for testing some of the most promising ideas for technology development.

This in fact is what we believe is needed: the investment in a new, large scale experimental research facility or perhaps a set of several intermediate size experimental research facilities to address the basic issues of increased safety, reduced proliferation, and improved waste disposal. Such a flagship facility or set of facilities, built at one or several of our national laboratories, is crucial if we are serious about keeping nuclear power as a viable option for the future. It would also generate sufficient national interest to attract new nuclear engineers to the energy field so that the country does not lose this vital technical expertise due to attrition in the near term future. Such a facility or facilities and the associated research program will require funding at a much higher level than the currently requested funding, closer to $250M to $300M per year.

In order to decide upon the specific mission and corresponding facility or facilities, a national debate is required during the coming year involving DOE, universities, and industries, with DOE taking the lead as organizer and facilitator. A number of new concepts aimed at exploring the scientific foundations of nuclear energy production would have to be considered and peer reviewed before deciding on the scope of the mission and the design of the experiment or experiments. Several of the specific issues that might be considered solely or in combination within the mission of the experiment program include the following:

2. DOE should reaffirm its commitment for plasma science and fusion engineering. It should commit to a long-term research program funded at a stable, realistic level commensurate with the long-term nature of the project. A stable program would again attract a substantial number of excellent students enticed by the dream of fusion and the difficult intellectual challenges.

3. DOE should enhance the funding of radiation science applications in the biomedical fields under a newly designated program within DOE similar to basic energy sciences and high energy physics. The program can be responsible for science and technology development in the areas of:

5. For the success of the spent fuel disposal program and the maintenance of our nuclear engineering infrastructure it is imperative that OCRWM the DOE-OCRWM restore its educational program to its former levels of activity. The technical challenges of spent fuel, ranging from criticality studies to heat transfer, to cask design and performance, to shipping, receiving and final packaging, present outstanding opportunities for the nations nuclear engineering educational programs to develop innovative solutions while educating the workforce and future leaders for DOE who will successfully close the nuclear fuel cycle. 6. Similarly, it is imperative that a portion of the massive sums involved in the cleanup activities of former sites for production of strategic material be directed to nuclear engineering programs. This will help DOE-EM achieve its objectives of creating a better prepared workforce for the EM programs as well as tap into the university resources for innovative solutions to the cleanup problems.

7. DOE should encourage the university community to advance radiation applications in medicine and other fields by supporting the establishment of a number of university based centers or consortia consisting of universities, hospitals and national laboratories. These centers should be able to support the operation of university research reactors and other radiation production facilities to enable students and faculty from several universities to experiment with advanced technologies prior to their implementation for routine use.

8. DOE should enhance the existing support for the educational programs and infrastructure in nuclear engineering and university reactors through (a) direct funding of competitive single investigator proposals for research and research equipment, (b) supporting an appropriately sized scholarship and fellowship program which also covers postdoctoral fellowships, (c) providing the fuel needed to operate university reactors, (d) upgrading several university research reactors and (e) providing wider support for young faculty initiatives. A doubling of the funding in the university support budget to $25M can be justified given the new vision for a unified nuclear engineering curriculum that prepares the students for careers in nuclear energy and a wide range of radiation science applications.

This document was formally approved by the entire Nuclear Engineering Heads Organization.