activity is 2.6% of the initial atl activity. Because the present
241
Pu activity in the
soil is about seven times that of 2??+240 Pu, the final 241A soil activity resulting from
the decay of 7+! pu will be 0.18 that of
concentrations are 0.7 that of
241
Am resulting from
24)
23942405
2394240
Pu.
The currently observed 241 Ay soil
Thus, the final total soil concentration of
241
Am now present and that resulting from
0.88 (0.7 + 0.18) that of the existing 727*2#0 Pu
soil concentrations.
Pu decay will be
For estimates of
dose via inhalation, the eventual 241 Am soil concentrations can be considered equal to the
23942405, concentrations.
As a result, the doses calculated for 239+240p, can be
doubled to account for the 24! am,
102
T
7
T
TT
F \
ba
L
Zz
=
10-¢
F
2
C
=
T
TFT
“Ty
T
T
T
7
241 by activity
7
\
4
\\
\
4
\
\\
sfL
2
\
z4
a
\
‘\
& 26 — poe
eof
1
:
241 am activity _
\
\
1
\
z
\
q
241 Puactivity ..
4
1 241 Am activity
0.1
pop gt
0
4
tt a
40
80
7
S
f \
120
Time (y)
Figure 2. Relationship between parent aul Pu activity and daughter 241 amy activity.
1D