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It may be noted that z is defined as the ratio of the fraction of the
nuclide contained in the particles to that not contained in the particle
(i.e. lost from the particle) assuming r, for the reference nuclide
(usually Mo99 ) is unity. With this definition, Eq. 31 has no real significance except for the cases where all rj are either 1 or O or where

2% is taken to be proportional to the average value of z,(j) for the
mixture. With the latter of the two views of 22, the data of Table 1
and Fig. 1 were used to obtain values of k, forShots Zuni, Tewa, and
Coulomb C, and z2 for Shots Shasta, Tewa and Zand, for applicstion at

H+lhr.

The respective k, values are 8.1 x 10°, 9.6 x 10, and

4.5 x 1079; the respective 22

values are 0.41, 0.65, anf 0.73. Since

Shot Tewa was detonated in 2>°feet of water, the values of
for only
the Zuni and Coulomb C Shots were used for obtaining constants for an

assumed dependence of k, on weapon yield and the z2, values for Shasta
(Diablo) and Zuni were used for a scaling function’for Zo The two
assumed empirical functions are

k, = 4.1 x 1079 wor®

(32)

and

o

_

Ze, = 0.32 wo

086

(33)

in which the respective values apply only to determining ep at H +1 br
where

oe
Kk
+z
tp
By Eq. 34 rp,

(34)
por/NW

can approach unity as the distance increases.

Equation 32

indicates that Tey approaches unity at shorter distances as the yield

decreases, and Eq. 33 indicates that the fractionation decreases as the
yield increases. These trends in fractionation correspond to the observed data. The constants are adjusted to rp,
values with respect to
and assume no difference between coral and
NTS soil.
The values of zp,

devices are given in

and k, for the fallout from some of the test

Table 9.

The fallout from the surface water (barge)

shots of yield 5 MT and larger is assumed to be unfractionated.

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