Table B-2-3. Post-Cleanup TRU/Am Ratios on Irene
Location
TRU/Am
13-N-2
12-N-2
9-5-3
12-N-1
14-N-1
8.48
6.57
7.70
7.34
9.36
10-N-1
7-8-3
10.23
11.39
§-S-2
6.06
DETERMINATION OF THE PLUTONIUM TO AMERICIUM
RATIO IN SOIL SAMPLES FROM ISLAND VERA
DOE/ERSP TECH NOTE NO. 2.2
DATED: 21 November 1977
AUTHOR: B. Friesen, DRI
Reference Tech Note 2.0 for introductory remarks.
Determination of
one
mean
ratio
for
Vera
was
made
including
238,239,240py
and
24lam,
Laboratory results of eight soil samples taken from four locations on the island were used to
compute a ratio for each sample. The weighted mean of these eight numbers was 1.55 with a
coefficient of variation of 17.7%. The range in values was 1.26 to 2.09.
Determination of the error term to associate with the mean ratio was accomplished as described in
Tech Note 2.0. The Vera data has a weighted mean ratio and error term of 1.572+0.415, as
presented below, and these were used in the computations to derive total plutonium estimates and
upper bounds.
"A" Samples
Ratio No.
1
3
5
7
Simple Mean
Weighted Mean
Weighted Mean
(all samples)
"B" Samples
Ratio
Ratio No.
Ratio
2.09
1.73
1.62
1.60
2
4
6
8
1.26
1.32
1.33
1.45
1.76
1.34
1.77
1.34
1.572
B-2-11