cop fee r= - ga +r .siete (continuad) - “ER radioactivity stay in the sir. I have here an RRL acme of you have already seen published in the Journal physical Research. The ERL pecple made studies ou the chnosr tration of naturel radioactive decay products in the at making certain assusptions about the rate at which they produced, that the "mean life of each substance due te ndz radioactive loss," that is due to sume sort of removal process, “vas about ten days." I think that the question of how long radioactivity, once itgot into lower layers, would last. WEILM: Bow levi KELIOGGs Well, thelr observations vere made at the ground, but p: VOICE: Don't thesethings oome from the ground? KELICOG: This is nt a cloud, thene are natural ratonctve ; VOICE: Tan't this radon fromthe ground, going wt KELLOGG: (7) Tete KELLOGG s Radon from the soil and it's decay products. MW ee) co oS (ca —<_, ny Ln ema rndingn ware than Mo cme wth «otha oA, | : like that? 4 -EREESIAN: (7) - a7