Ft. 100,000 F777 F oT ToT ales Zs 166 “162 175 187 i 73 Ines 162 102 0476 | 60,000 al63 172 89 iT2 102 83 “77 Oe 179 O NRL SURFACE STATION \7 150 59 48 5 40,000} 023 1} ~* J hor [73 |68 pols 229||175 | 4 67 _TROPOPATISE 64 a&F a 0.4 4- ae 32 15 0 0.06 25 - 20 221 0100 1S 560 ~ O17 15 4 "39 ral ~ | _ 1g O,7 0.4 a03 0.8 20,000}- res 4 330 gl? MEAN eA 6.9 L 30 & SAN ANGELO BALLOON STATION ots ~ TTF ]Q AIRCRAFT OBSERVATION 156 80,000/- Km. noe ‘if O Og 012 . 53 O48 - 0 Of 09 - 10 0 0.04 0.07 ao 0-4 - 5 0.2 °o 02 OUod 90° | 0.3 60° yw 0.5 0.5 ii gy 30° 0.05 Ib. 003 lo O° O30; tg 0.05 it 8 NORTH 30° SOUTH Sr°° d/m/1000 scf Fig. 2 -- Strontium-90 distribution 28 005 0.05 Oe 60° uo 30°