Constructing Predictive Estimates for Worker Exposure to Radioactivity During Decommissioning: Analysis of Completed Decommissioning Projects - Master Thesis

Abstract

An analysis of completed decommissioning projects is used to construct predictive estimates for worker exposure to radioactivity during decommissioning activities. The preferred organizational method for the completed decommissioning project data is to divide the data by type of facility, whether decommissioning was performed on part of the facility or the complete facility, and the level of radiation within the facility prior to decommissioning (low, medium, or high). Additional data analysis shows that there is not a downward trend in worker exposure data over time. Also, the use of a standard estimate for worker exposure to radioactivity may be a best estimate for low complete storage, high partial storage, and medium reactor facilities; a conservative estimate for some low level of facility radiation facilities (reactor complete, research complete, pits/ponds, other), medium partial process facilities, and high complete research facilities; and an underestimate for the remaining facilities. Limited data are available to compare different decommissioning alternatives, so the available data are reported and no conclusions can been drawn. It is recommended that all DOE sites and the NRC use a similar method to document worker hours, worker exposure to radiation (person-rem), and standard industrial accidents, injuries, and deaths for all completed decommissioning activities. iv ACKNOWLEDGEMENTS

Environment, Safety, and Health Risk Assessment Program (ESHRAP)

“…For D&D activities, the numbers of involved workers associated with large facilities and the times to complete the activities were estimated from information presented in Dettmers (2002). In general, information from that source is limited and was presented for combinations of activities.…”

“…For those activities, a large facility was defined based on the building footprint (2000 m 3 ) and number of stories (1), and the processing rate unit is 2000 or 5000 m 2 /y, except for characterization, which is 25,000 m 2 /y. Again, information was obtained from Dettmers (2002).…”