[en] Neutron radiation from the JANUS reactor at Argonne National Laboratory is being used with increasing frequency for major biological experiments. The fast neutron spectrum has a kerma-weighted mean energy of 0.8 MeV and low gamma ray contamination. In 1984 the JANUS fission converter plate of highly enriched uranium was replaced by one made of low enriched uranium. Microdosimetric spectra were recorded at several different positions in the high flux irradiation room of JANUS before the change of the converter plate. Each set of measurements consisted of spectra taken at a simulated site diameter of 1''mu''m in both ''attenuator up'' and ''attenuator down'' configurations. At two conventional dosimetry reference positions, two sets of measurements were recorded. At three biological reference positions, measurements simulating several biological irradiation conditions were taken. The dose rate at each position was estimated and compared with dose rates obtained previously by conventional dosimetry. Comparison of the different measurements showed no major change in spectra as a function of position or irradiation condition. First results from similar sets of measurements recorded after the installation of the new converter plate indicate no major change in the spectra. (author)

[en] Argonne National Laboratory has begun the decontamination and decommissioning (D ampersand D) of the JANUS Reactor Facility. The project is managed by the Technology Development Division's D ampersand D Program personnel. D ampersand D procedures are performed by sub-contractor personnel. Specific activities involving the removal, size reduction, and packaging of radioactive components and facilities are discussed

[en] This paper focuses on the lessons learned during the decontamination and decommissioning (D and D) of two reactors at Argonne National Laboratory-East (ANL-E). The Experimental Boiling Water Reactor (EBWR) was a 100 MW(t), 5 MSV(e) proof-of-concept facility. The Janus Reactor was a 200 kW(t) reactor located at the Biological Irradiation Facility and was used to study the effects of neutron radiation on animals

[en] A research reactor for exclusive use in experimental radiobiology was designed and built at Argonne National Laboratory in the 1960's. It was located in a special addition to Building 202, which housed the Division of Biological and Medical Research. Its location assured easy access for all users to the animal facilities, and it was also near the existing gamma-irradiation facilities. The water-cooled, heterogeneous 200-kW(th) reactor, named JANUS, became the focal point for a range of radiobiological studies gathered under the rubic of open-quotes the JANUS programclose quotes. The program ran from about 1969 to 1992 and included research at all levels of biological organization, from subcellular to organism. More than a dozen moderate- to large-scale studies with the B6CF₁ mouse were carried out; these focused on the late effects of whole-body exposure to gamma rays or fission neutrons, in matching exposure regimes. In broad terms, these studies collected data on survival and on the pathology observed at death. A deliberate effort was made to establish the cause of death. This archieve describes these late-effects studies and their general findings. The database includes exposure parameters, time of death, and the gross pathology and histopathology in codified form. A series of appendices describes all pathology procedures and codes, treatment or irradiation codes, and the manner in which the data can be accessed in the ORACLE database management system. A series of tables also presents summaries of the individual experiments in terms of radiation quality, sample sizes at entry, mean survival times by sex, and number of gross pathology and histopathology records

[en] Neutron radiation from the JANUS reactor at Argonne National Laboratory is being used with increasing frequency for major biological experiments. The fast neutron spectrum has a Kerma-weighted mean energy of 0.8 MeV and low gamma-ray contamination. In 1984 the JANUS fission converter plate of highly enriched uranium was replaced by one made of low-enriched uranium. We recorded microdosimetric spectra at several different positions in the high-flux irradiation room of JANUS before the change of the converter plate. Each set of measurements consisted of spectra taken at three different site diameters (0.5, 1.0, and 5.0 μm) and in both ''attenuator up'' and ''attenuator down'' configurations. At two conventional dosimetry reference positions, two sets of measurements were recorded. At three biological reference positions, measurements simulating several biological irradiation conditions, were taken. The dose rate at each position was estimated and compared with dose rates obtained previously by conventional dosimetry. Comparison of the different measurements showed no major change in spectra as a function of position or irradiation condition. First results from similar sets of measurements recorded after the installment of the new converter plate indicate no major change in the spectra. 11 refs., 4 figs., 5 tabs

[en] The performance and fuel cycle costs for a 25 MW, JANUS 30 reactor conceptual design by INTERATOM, Federal Republic of Germany, for BATAN, Republic of Indonesia have been studied using 19.75% enriched uranium in four fuel element design options. All of these fuel element designs have either been proposed by INTERATOM for various reactors or are currently in use with 93% enriched uranium in reactors in the Federal Republic of Germany. Aluminide, oxide, and silicide fuels were studied for selected designs using the range of uranium densities that are either currently qualified or are being developed and demonstrated internationally. To assess the long-term fuel adaptation strategy as well as the present fuel acceptance, reactor performance and annual fuel cycle costs were computed for seventeen cases based on a representative end-of-cycle excess reactivity and duty factor. In addition, a study was made to provide data for evaluating the trade-off between the increased safety associated with thicker cladding and the economic penalty due to increased fuel consumption

No abstract available

[en] Fission-spectrum neutrons from the Janus reactor at Argonne National Laboratory were compared with γ-rays in terms of their relative biological effectiveness (RBE) for embryolethal and teratogenic effects in mice. No evidence was found of any processes that were abnormally sensitive to neutrons. The RBE for killing embryos and producing abnormal embryos or specific abnormalities was between 2 and 3. This is close to the values found in other systems for processes involving cell killing. (U.S.)

[en] The US Department of Energy (DOE) Chicago Operations Office and the Federal Energy Technology Center (FETC) jointly sponsored a Large-Scale Demonstration Project (LSDP) at Argonne National Laboratory-East (ANL). The objective of the LSDP is to demonstrate potentially beneficial Deactivation and Decommissioning (D and D) technologies in comparison to current baseline technologies. The objective of remotely removing and packaging radioactively contaminated concrete during the D and D process is to reduce worker exposure rates, heat stress and injury to personnel. To achieve this objective, the Brokk Remotely Operated Concrete Demolition System was demonstrated in August and September, 1997 at the Janus Research Reactor located in Building 202 of ANL. The Brokk BM 150, manufactured by Holmhed Systems AB of Sweden and supplied by Duane Equipment Corp., uses a remote operated articulated hydraulic boom with various tool head attachments to perform the work. The machine is designed primarily to drive a hammer and has a reach of fifteen feet. The Brokk can be operated by someone 400 feet away or in a different room with a TV monitor. The machine can be operated up to a 30-degree gradient. The unit requires a 480-volt, 50-amp circuit for its power source. Two attachments were used in this demonstration. The hydraulic hammer and the excavating bucket. The hammer operates at 600 foot pounds and has outputs of 1000 to 1500 beats per minute. The bucket has a capacity of 1/4 cubic yard and has a smooth cutting edge. Other attachments available include a concrete crusher, a La Bounty shear, and a 1/4 yard clamshell bucket. Smaller and larger sizes of the Brokk are available from Duane Equipment Corporation

[en] Argonne National Laboratory (ANL-E) has recently completed the decontamination and decommissioning (D and D) of the JANUS Reactor Facility located in Building 202. The 200 KW reactor operated from August 1963 to March 1992. The facility was used to study the effects of both high and low doses of fission neutrons in animals. There were two exposure rooms on opposite sides of the reactor and the reactor was therefore named after the two-faced Roman god. The High Dose Room was capable of specimen exposure at a dose rate of 3,600 rads per hour. During calendar year 1996 a detailed characterization of the facility was performed by ANL-E Health Physics personnel. ANL-E Analytical Services performed the required sample analysis. An Auditable Safety Analysis and an Environmental Assessment were completed. D and D plans, procedures and procurement documents were prepared and approved. A D and D subcontractor was selected and a firm, fixed price contract awarded for the field work and final survey effort. The D and D subcontractor was mobilized to ANL-E in January 1997. Electrical isolation of all reactor equipment and control panels was accomplished and the equipment removed. A total of 207,230 pounds (94,082 Kg) of lead shielding was removed, surveyed and sampled, and free-released for recycle. All primary and secondary piping was removed, size reduced and packaged for disposal or recycled as appropriate. The reactor vessel was removed, sized reduced and packaged as radioactive waste in April. The activated graphite block reflector was removed next, followed by the bioshield concrete and steel. All of this material was packaged as low level waste. Total low level radioactive waste generation was 4002.1 cubic feet (113.3 cubic meters). Mixed waste generation was 538 cubic feet (15.2 cubic meters). The Final Release Survey was completed in September. The project field work was completed in 38 weeks without any lost-time accidents, personnel contaminations or unplanned exposures. The project was managed by the ANL-E Technology Development Division's D and D Program personnel. Total cost of the project was $2,095,000.00. Total project exposure was 0.482 person rem (4.82 mSv). Detailed information on D and D methods and lessons learned are presented