Computerized Methodology for Evaluating the Long-Range Radiological Impact of Shallow-Land Burial

摘要

A computerized methodology has been implemented to calculate the risk to local and intermediate-range (up to 80 km distant) populations resulting from water- and air-borne transport of radionuclides present in low-level wastes buried in shallow trenches such as those used at Oak Ridge. Our computer code, PRESTO (Prediction of Radiation Effects from Shallow Trench Operations), was developed under United States Environmental Protection Agency funding to evaluate possible health effects resulting from shallow burial operations. Sources of contamination include radionuclide releases from the trenches and from areas contaminated with operational spillage. The model is intended to predict radionuclide transport and the ensuing exposure and health impact to at-risk populations for a 1000-year period following cessation of burial ground operations. Several classes of submodels are used in PRESTO to represent scheduled event, unit system response, and risk evaluation processes. Examples of scheduled events are trench cap failure, stabilization of insoluble surface contaminant, the onset of farming or reclamation practices, and human intrusion. Unit system response submodels simulate processes such as infiltration of rainwater into the trench and erosion of soil overburden from the trench cover. System response submodels generate parameters used repeatedly in the 1000-year simulation loop. (ERA citation 06:019900)