Externe | rnLOSE Concentration(nlcroeuries Theoretical Maxirux per milliliter extrapolat- Whole-body Garma ed to 3 days after detonaInfinity Dose (reantzens) Virgin River Irrigation Canal, Bev 8.7 x 1079 6. Irrigation Ditch, 56 mi.no. of Pioche, Kev 4.5 x 10-5 0.15 lover Pahranagst Lake, Bev 3.2 x 10-6 2. Virgin River at Mesquite, Rev 2.6 x 107 Bunkerville, Nev (tap water) 1.2 x 10-6 2.5 7.0 . 1.1 x 10-6 Crystal Springs, Bev (tap water) 0.15 - Dae to veather and to attenuation of the gamua rays by buildings, the whole-body gana dose estizated to have been actually delivered was probably @loser to one-half of the values show. The xaximm permissible concentration of fission products in drinking water is § x 10-3 po/ul extrapolated to three days after detonation, This is considered a safe concentration for continuous consueption. Whereas, the monitoring of vater sources is of value for docusentary purposes it should be recognised that the concentrations found may vary widely vithin snall geographical areas and even at the same loeation at different tines (taking into account radioactive decay), Thus, eonfidence eannot be placed {fn precise values. Table ¥i.a. suggests that even if one were to have stored up the water listed at Virgin River Irrigation Canal and subsisted entirely on this for a lifetine, the concentration vould be ~ m7 / n . we t