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

0977-6Version 16.1.3 B1c – Geotechnical Investigations: Laboratory AnalystFigure 6.11 and Figure 6.12 show the total dose to a technician examining a sample inthe year 2230 and in the year 7000, respectively, for investigations at differentlocations across the facility.The results are similar in form to those for the trial pit digger, with the wastes inVault 15 (grid cell C10) generating the highest doses during sample analysis. Thehighest calculated dose at 2230 at grid cell C10 is 2.3 x 10 -5 mSv and the mostsignificant radionuclides in terms of contribution to dose are 239 Pu and 240 Pu,following 137 Cs and 241 Am decay (Figure 6.13). The key dose pathway is dustinhalation (Figure 6.14).As discussed in Sections 2 and 5.2, it has been assumed that one technician could beinvolved in the examination of 25 samples during a site investigation. If the 25samples were taken from grid cell C10, the dose received by the technician would beabout 5.9 x 10 -4 mSv. Realistically, the dose received would be lower than thisbecause samples would be taken from across the site; the calculated dose ranges from1.2 x 10 -5 mSv in grid cell E10 (Vault 17) to 2.3 x 10 -5 mSv in cell C10 (Vault 15) at2230.0.0000250.000020Dose (mSv)0.0000150.0000100.0000050.000000A & B10C & D11E & FFigure 6.11Total dose from laboratory analysis (B1c) of a sample taken fromgeotechnical investigations at different locations in the year 2230(Case A).Galson Sciences Ltd 28 21 March 2011