Results

Outside the subsurface deposits, the average TRU concentration before any excision was 131 pCi/g,
and after all lifts the average was 31.8 pCi/g. Therefore,

k
ky

ecd
ed

1
ed

=
=

131
31.8

=

31.8 = 0.2427

T3

=

In (0.2427) = 1.4158

=

0.7063

and the average concentration in soil removed was

131 x 0.7063(1 - 0.2427) = 70.1 pCi/g.
Then the total activity removed is

70.1 pCi/g x eubie yards excised x 1.185 10-6(Ci/yd3)(pCi/g).
In the areas with subsurface contamination, the assumption was made that the total soil depth lifted
was approximately 50 em. The top 20 em, or 0.4 of the total volume for these areas, was soil having
a linear gradient, and the remaining 30 em (0.6 of the total) was soil with an exponential gradient.
Thus, for the top 20 em, the before-excision average was 203 pCi/g TRU, and the after-excision (one
lift only) value was 194 pCi/g TRU. So the average for the top 20 cm was

0.5(203 + 194) = 198.5 pCi/g.
For the remaining soil the "before" excision value is the value after one lift, 194 pCi/g, and the
average after all excision was 85.4 pCi/g. Then, for the remaining 30 em,
= 194
ay

k

ky = 85.4

ky

ke" 0.4402

1 = 1.2187
ed

and the average was

- 0.4402) = 132.4 pCi/g.

The average concentration for the entire profile was therefore
0.4(198.5)

+ 0.6(132.4)

~

194 x 1.2187(1

= 158.8 pCi/g TRU.

Then the total activity removed from these areas was
158.8 x total volume removed from these areas x 1.185 x 10-6,

arm

The total activity removed from Kickapoo is the sum of the activity removed from the "without
subsurface contamination" and "with subsurface contamination" areas.

B-10-3

Select target paragraph3