Nuclear Reactor Laboratory
The Nuclear Reactor Laboratory (NRL) is an interdepartmental center that operates a 5 MW research reactor in support of MIT's educational and research missions. This reactor, which is designated as the MITR, is a heavy-water reflected, light-water cooled and moderated nuclear reactor that utilizes flat, plate-type, finned, aluminum-clad fuel elements. The average core power density is about 70 kW per liter. The maximum thermal neutron flux available to experimenters is 5 x 1013 neutrons/cm2s. The reactor is the NRL's principal experimental facility.
The past year has been a very active one for the NRL. The relicensing of the MITR with a concomitant upgrade in power is in progress. The Nuclear Regulatory Commission (NRC) has authorized the continued operation of the MITR pending its review of the application that was filed in 1999. That process remains ongoing. In conjunction with the relicensing effort, reactor systems are being upgraded. Upgrades to electrical distribution systems were initiated in 2000. New control blades and control blade drives will be installed in 2001. In addition, in order to support the future of the MITR and university research reactors in general, John A. Bernard, Director of the MITR, worked closely with members of the MIT Administration, the U.S. Department of Energy (DOE), and the university research reactor community. As a result of these actions, additional funding has been promised to the MIT Administration by the DOE in support of the MITR and certain government funding options are being established as a means of strengthening university research reactor programs around the United States.
There were also several especially noteworthy developments concerning the continued program in joint research with Beth Israel-Deaconess Medical Center (BIDMC) on the treatment of cancer utilizing the boron neutron capture method during the past year. These include the characterization of the Fission Converter Epithermal Beam Medical Facility which is now ready for BNCT Clinical Trials. After more than a decade of research, design, and construction, MIT now has the best epithermal beam for neutron capture therapy in the world. Major initiatives were undertaken last year by both BIDMC and the MIT Staff to explore funding opportunities through the National Institutes of Health (NIH), and the National Cancer Institute (NCI) as well as other sources. This initiative included several grant proposals that were submitted to NIH and NCI. As a result of these efforts, funding for a phase I/II study of tumor response and normal brain was approved by the NIH. The DOE, which funded the fission converter beam and facility, has also indicated that it will cover MIT costs (labor and neutron charges) related to BNCT trials. It is anticipated that the NIH will also fund a phase II study on melanoma of the extremities.
As in past years, the NRL continued its joint interdisciplinary activities with both MIT and non-MIT collaborators, including academic departments and interdepartmental laboratories and a number of other universities, schools, and nonprofit research institutions such as teaching hospitals. These joint research or teaching and training activities cover a wide spectrum in the life and physical sciences and in engineering, including development of cancer therapy, nuclear engineering, computer control of reactors, training in reactor operations, dose reduction and materials performance in power reactors, radiochemistry and trace analysis applied to the health effects from energy use, nutrition, earth and planetary sciences, environmental studies, and nuclear medicine.
The prompt gamma neutron activation analysis facility was used both for research and in support of the neutron capture therapy clinical trials.
Professor Frederick A. Frey, Department of Earth, Atmospheric and Planetary Sciences, and Dr. Pillalamarri Ila supervise operation of the Neutron Activation Analysis Laboratory which is part of the Center for Geochemical Analysis within the Earth, Atmospheric and Planetary Sciences Department. Trace element abundances are determined in a wide range of natural materials. Currently the laboratory is focused on analyses of volcanic rocks recovered during the ongoing Hawaiian Scientific Drilling Project and the recently completed Leg 183 of the Ocean Drilling program which focused on sampling the very large igneous province that forms the Kerguelen Plateau.
The NRL also operates its own Trace Analysis Laboratory and made its neutron activation analysis (NAA) facilities and expertise available to industry, other universities, private and governmental laboratories, and hospitals. Research and/or service-oriented collaborations were continued with several MIT research laboratories as well as with other educational and research institutions including: Harvard, California Institute of Technology, Tufts University, University of Utah, University of Connecticut, and the Woods Hole Oceanographic Institute.
Within MIT, research support has been provided to several departments. This research support includes analysis of various environmental and biological samples for trace and toxic metals for Professor William G. Thilly (Center for Environmental Health Sciences) as well as for faculty in both the Department of Civil and Environmental Engineering and the Department of Chemical Engineering.
A number of other research applications of NAA are summarized in a subsequent section, Reactor Irradiations for Research Groups outside MIT.
A fission converter based epithermal neutron beam irradiation facility for BNCT was constructed over a period of 2.5 years and was successfully put into operation during this year. The intensity of this beam has been measured and it is the highest intensity beam available anywhere in the world. The beam quality has also been experimentally verified and it is of near theoretical purity. Irradiation times will be as short as a few minutes and therapeutic ratios (dose to tumor/dose to normal tissue) will be 4-5, a doubling over the therapeutic ratio available with the previous MIT epithermal neutron beam. In addition, the Fission Converter Epithermal Neutron Beam Medical Facility was also completed. This facility is now available and will provide a high intensity and high purity epithermal neutron beam for BNCT irradiations of human cancers. This new facility will be the key component in future clinical tests of the efficacy of BNCT for cancer. It will also assure that MIT will maintain its leadership role in this research area.
A contract has been continued with the DOE for the reconstruction of the medical irradiation beam in the basement of the MITR. When completed this facility will provide a high intensity and high purity thermal neutron beam for BNCT irradiations of small animals and superficial human cancers.
BNCT research at the MIT Research Reactor is under the direction of Professor Otto K. Harling and is carried out in collaboration with the medical staff at the Beth Israel-Deaconess Medical Center. Several MIT graduate students are completing their theses on these projects.
The NRL supports a subdiscipline in the Nuclear Engineering Department (NED), Radiation Health Physics, by providing relevant research opportunities. The NRL also contributes to a specially designed laboratory and demonstration course. This course, 22.09/22.104, Principles of Nuclear Radiation Measurement and Protection, is appropriate for all students in NED. Research topics and support for health physics students were provided by NRL projects, especially the BNCT and Dose Reduction projects of Professor Otto K. Harling.
Dr. John A. Bernard, who is certified as a Health Physicist by the American Board of Health Physics, continued to teach course 22.581, Introduction to Health Physics. This course uses the MIT Research Reactor to provide practical examples of health physics issues.
A new in-core autoclave facility was successfully built to study the effect of radiation on candidate ceramic clads. The benefit to the use of such clads is the elimination of the potential for a steam-zircaloy reaction that now exists with the zirconium-based clads that are currently in use. The program was funded by Gamma Engineering Corporation under a DOE Nuclear Engineering Research Initiative Grant.
An in-core loop to study the causes of "shadow corrosion" is now being designed and installation is expected late in 2001.
Dr. Bernard continued to teach course 22.921 Reactor Dynamics and Control and to offer review classes on engineering fundamentals for NED students in the radiological sciences. Both activities make use of the reactor for illustrating theoretical concepts. The program on the digital control of nuclear reactors continued with thesis activity in the area of automated diagnostics. One student completed a Ph.D. in this area during the past year.
The relicensing of the MITR with a concomitant upgrade in power is in progress. It was previously identified that the MITR could operate at a maximum power of 6-7 MW with the existing heat removal equipment. A decision was subsequently made to submit the licensing documents for a power increase from 5 MW to 6 MW. On July 8, 1999, a formal application was submitted to the U.S. Nuclear Regulatory Commission (NRC) to relicense the reactor for an additional twenty years and to upgrade the power level to 6 MW. The relicensing package included a complete rewrite of the Safety Analysis Report and the Technical Specifications. The NRC has authorized the continued operation of the MITR pending its review of the application. That process remains ongoing. In conjunction with the relicensing effort, reactor systems are being upgraded. Upgrades to electrical distribution systems were initiated in 2000.
In nuclear medicine, the development and/or continuing production of radioisotopes for use by researchers at hospitals and other universities included investigations using track etching techniques by Dr. David Slaughter of the University of Utah to determine the uptake pattern of heavy metals by humans as well as the environment, and evaluation of copper and gold for arthritis treatments by Dr. Alan B. Packard of Children's Hospital.
In a number of other areas reactor irradiations and services were also performed for research groups outside MIT. Most of these represent continuations of previous research. Examples include Dr. Alan P. Fleer of Woods Hole Oceanographic Institute who used irradiation to determine natural actinides and plutonium in marine sediments and Dr. Rebecca Chamberlain of the Los Alamos National Laboratory who is investigating calibration of ultra-sensitive neutron monitoring devices by thermal neutron fission of uranium foils, as well as isotope production for cardiovascular research by both Best Industries, Inc. (Springfield, VA) and Implant Sciences (Wakefield, MA).
Whereas most of the outside users pay for irradiation services at the reactor, educational institutions needing such services for their own academic or research purposes are assisted in this regard by the DOE through its "Reactor Sharing Program." A grant to MIT NRL reimburses us for the costs of providing irradiation services and facilities to other not-for-profit institutions (including teaching hospitals and middle and high schools). Under this program, 500 students and 50 faculty and staff from over 30 other educational institutions benefited from visits to and use of the MITR during the past year.
Research utilization of the MITR by other institutions under the Reactor Sharing Program during the past year has included: use by Professors J. Christopher Hepburn and Rudolph Hon of Boston College to activate geological specimens and standards for the neutron activation analysis of rare earth and other trace elements in studies of the geological development of the northeastern United States; irradiation of coal ash samples for research being conducted by Professor JoAnne Lighty at the University of Utah, gamma irradiation of plant seeds for several area high school students participating in science fair projects; measurements of boron concentration and work on high resolution track etch autoradiography for Professor Robert Zamenhof of Beth Israel - Deaconess Medical Center; participation in several special high school student projects; neutron activation analysis of subsurface water supplies by Professor Jack Beal at Fairfield University; neutron time-of-flight and Bragg angle measurements by Professor Martin Posner's group at the University of Massachusetts; NaOH irradiation for Professor Clayton French of UMass-Lowell; and use of neutron activation analysis for Bromine measurements by Professor Joseph Kehayias (Tufts) and Senior Research Scientist Richard Lanza (MIT NED) to evaluate intra/extra-cellular water as an indicator of overall human health.
For education of the general public and students at all levels in local and other New England schools, the reactor staff provides lectures and tours periodically throughout the year.
The MITR produces about $1.2 million worth of neutron transmutation doped (NTD) silicon per year. This is commercial income and the funds are used to offset operating costs. The market for NTD silicon remains strong despite improvements in the chemical production of the material. At present, demand exceeds the MITR's capacity.
A major project to neutron transmutation dope semiconductor grade silicon single crystals continued for a successful eighth year. Approximately 10 metric tons of Si crystals were accurately irradiated in shielded, automated irradiation facilities at the MITR. This project is under the technical direction of Professor Otto K. Harling.
The NRL supports the affirmative action goals of the Massachusetts Institute of Technology. Of a staff of 37 there are currently five engineering and management positions held by minorities and women. The NRL participated in the U.S. DOE's program for minority training in reactor operations, and one of our current senior reactor operators is a graduate of this program.
The MIT Reactor completed its 43rd year of operation, its 27th since the 1974-75 shutdown for upgrading and overhaul. The reactor operated continuously (seven days per week) to support major experiments. On average, the MIT Reactor was operated 134 hours per week at its design power level of 5 MW. Energy output for the MITR-II, as the upgraded reactor is now called, totaled 512,000 megawatt-hours as of June 30, 2001. The MITR-I generated 250,445 MW in the sixteen years from 1958 to 1974.
The senior reactor staff continued to be active in the nuclear field. Dr. Bernard completed his term on the Board of Directors of the American Nuclear Society (ANS) and Dr. Hu was elected Chair of the Isotopes and Radiation Division of ANS with her term scheduled to start in June 2002.
To summarize briefly the reactor was well utilized during the year, although still more experiments and irradiations can be accommodated because of the number and versatility of the many experimental facilities. The number of specimen irradiations was 370. There were 78 irradiations in the medical rooms, many in support of the neutron capture therapy program for the treatment of brain cancer and subcutaneous melanoma. Theses and publications on research supported by the reactor are running at about 5 and 20 per year, respectively. A total of 1172 people toured the MIT Research Reactor from July 1, 2000 through June 30, 2001.