Leaching of radionuclides produced in soil and rock by high energy proton-induced radiation was studied for the SSC site. Comparison was made with predictions of a Monte Carlo code CASIM and previous results for the Fermilab site. The principal long-lived radionuclides were 3H and 22Na in agreement with Fermilab results. A few other radionuclides were present at lower concentrations in a subset of the samples. For example, 134Cs was detected in a few SSC water samples. Leaching from SSC chalk was dependent on previous weathering and on leaching time. The more soil-like marl and shale were leached more rapidly. Results of this study, in conjunction with the SSC groundwater model, show that adequate groundwater protection would have been maintained for an accidental loss of the entire proton beam at a point in the SSC Collider tunnel. Early warning techniques developed are directly applicable to soil activation monitoring at other facilities.

The application of ALARA (as low as reasonably achievable) principles to the design of new radiological facilities at Argonne National Laboratory provides a consistent radiation safety basis for future facility operations. This paper discusses the criteria for controlling radiation exposure and the techniques applied to meet those criteria for two new facilities. Argonne is a US Department of Energy (US DOE) laboratory, and the criteria are specified in the DOE Rule found at 10 CFR 835. The worst case radionuclides and their source strengths are chosen. Local shielding is specified to reduce dose rates to less than 50 μSv h−1at 30 cm from the shielding, thus avoiding the creation of a radiation area. Version 6 of the Los Alamos National Laboratory radiation transport code MCNP is then used to calculate the dose rates elsewhere. Based on the results of the calculations, design modifications are made to meet the design objectives criteria.

The Argonne National Laboratory-East (ANL-E) Environmental Radiation Monitoring System measures and records ambient radiation levels and provides detection capability for radon decay products in rain clouds. These decay products in rainwater tracked into a facility on the shoes of workers can cause false alarms from hand and shoe monitors. The monitors at ANL-E can easily detect the radon decay products, and the 19.6 and 26.8 min half-lives of the beta-particle emitters are long enough in many cases for sufficient activity to still be present to initiate a contamination alarm when the shoes are checked for radioactivity. The Environmental Radiation Monitoring System provides a warning when precipitation contains elevated levels of radon decay products. It is based on a prototype developed at the Super Collider Laboratory. During its first year of operation there were nine alarms from radon decay products with an alarm trigger point set at 30% greater than background. The alarms occurred at both monitoring stations, which are approximately 1,000 m apart, indicating large diameter radon clouds. The increases in background were associated with low atmospheric pressure. There was no correlation with radon released from the coal-burning steam plant on the site. Alarms also occurred when short-lived accelerator-produced radioactivity in the exhaust stack plume passed over the NaI(Tl) detector in one of the stations. The 450 MeV proton accelerator near the station produced 12C, 13N, and 15O by spallation of air nuclei. The gamma-ray spectrum from the plume from the accelerator exhaust stack was dominated by the 511 keV annihilation gamma rays from decay of these radionuclides. These gamma rays were easily distinguished from the 609 keV, 1,120 keV, and 1,764 keV gamma rays emitted by the radon decay products.

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