-5they arrive at the lower tropospheric levels.
.- Ultimate Br’? soil concentration, if present tropospheric activity levels
are maintained>
7
(= Ga x 207) e207) = 2x20! ayn/te.? -
or, by miltiplying by 2.8 x 107 £t2/mt® = 5.6 x 102La/ms®
¥
| and, by dividing by 2.2 x10? d/m/me := 2.5 x0 ne/mi®
. ir the present level has beena existence for 3 years and if negligible
a”1
levels were encountered prior to thie:
-
.
- _presdnt a? soillevel at Woshington,De.
yee.
* (2.5.x: 10° mo/mi? )x (1.eat)
oo
.
|
vhere x) =BB
|
and +t
“ 3 yr.
= 0.07 (2.5 x 10” m¢/mt?)
| z= 17
mC/mt2
-
|
These calculatias consider only that rein is the principle mechanism of
ex’? end BaD deposition and that similar efficiencies are obtained.
for either RaD or gr’? would serve ag @ check on these values.
Soil analysis
|
_ Libbey, in an address defore the American Physical Society, Philadelphia, Pa.
April 20, 1956, reported average total deposit of Br’. in US to be about 13 me/mi*,Ww
which is in reasonable agreemrit with the 17 me/mi= we estimated for a year leer. ny