Baldwin TD and Hicks TW, Assessment Calculations for Human ...

0977-6Version 1Table 2.1Exposure pathways modelled for each human intrusion event.Event/Exposure PathwayDescriptionEvent B1a: Geotechnical investigations – borehole drilling.Inhalation ofcontaminated dustIngestion ofcontaminatedmaterialExternal irradiationEvent B1b: Geotechnical investigations – trial pit excavation.Inhalation ofcontaminated dustIngestion ofcontaminatedmaterialExternal irradiationEvent B1c: Geotechnical investigations – laboratory analysis.Inhalation ofcontaminated dustIngestion ofcontaminatedmaterialExternal irradiationRadon and thoroninhalationEvent B3a: Housing development – construction.Inhalation ofcontaminated dustIngestion ofcontaminatedmaterialExternal irradiationEvent B3a: Housing development – occupancy.Inhalation ofcontaminated dustIngestion ofcontaminatedmaterialDust generated by a borehole intrusion into waste includes radioactivematerial. A worker inhales the dust during drilling activities.During drilling activities a worker ingests contaminated material as a resultof, for example, hand-to-mouth contact and licking of the lips.Contaminated material is left on the ground during drilling activities and aworker in proximity to this material is exposed to external irradiation.Dust generated by a trial pit excavation that intersects waste includesradioactive material. A worker inhales the dust during excavationactivities.During excavation activities a worker ingests contaminated material (e.g.through hand-to-mouth contact and licking of the lips).Contaminated material is left on the ground during excavation activitiesand a worker in proximity to this material is exposed to externalirradiation.Inspection of contaminated soil samples generates dust. The technicianinhales the dust during the analysis.During the analysis, the technician ingests contaminated material (e.g.through hand-to-mouth contact and licking of the lips).The analyst is exposed to external irradiation while inspectingcontaminated samples.The analyst is exposed to radon and thoron emanating from the sample.Concentrations of radon and thoron inhaled by the analyst depend on thelaboratory volume and ventilation rate.Excavations for a housing development intersect waste and generate dustthat includes radioactive material. A worker inhales the dust during theexcavation activities.During excavation activities a worker ingests contaminated material (e.g.through hand-to-mouth contact and licking of the lips).Contaminated material is left on the ground during excavation activitiesand a worker in proximity to this material is exposed to externalirradiation.Contaminated material is left on the ground at the site after construction ofa housing development. Wind action generates contaminated dust and asite occupant is exposed to the dust while outside.While outside (e.g. gardening), a site occupant ingests contaminatedmaterial (e.g. through hand-to-mouth contact and licking of the lips).Galson Sciences Ltd 5 21 March 2011