[en] A comprehensive radiological survey was conducted at Building 55 of the Chemicals Group, Olin Corporation, Joliet, Illinois. The survey included measurements of alpha and beta-gamma contamination, both fixed and removable; beta-gamma exposure readings at contact and at 1 m (3 ft) above the floor or ground level; estimates of radon-daughter concentrations in the air as airborne contaminants; and determinations of concentrations of ₁₃₇Cs, the ₂₃₂Th decay chain, the ₂₂₆Ra decay chain, and uranium in the soil on the site. Thirty-three spots or localized areas and three larger general areas within Building 55 exceeded the allowable limits as given in the Draft ANSI Standard N13.12 for uranium, and the general roof area exceeded the acceptable limits for radium-226. Additionally, two spots or localized areas on the roof substantially exceeded those limits. In 15 instances, the contamination was found to be removable from surfaces and readily available for transfer to other locations. Concentrations of radon daughters in the air of the building, as measured by grab-sampling techniques, were below the limit of 0.01 WL above background as given in the Surgeon General's Guidelines. Analyses of ten soil samples from the site indicated significantly elevated concentrations of uranium and radium at two sampling locations near Building 55. Based on a hypothetical exposure scenario, the maximum potential dose equivalent to an individual for external penetrating radiation resulting from exposure to radioactivity at this site was calculated to be 340 mrem per year. The internal radiation 50-year dose commitments from potential inhalation/ingestion of radioactive material were calculated to be 8300 mrem to the lung, 120 mrem to the bone, 26 mrem to the kidney, and 250 mrem whole body. Few individuals are expected to acquire such doses or dose commitments annually