BL
EL
E44
E6
£8
EO
El
=
w2
SANDB4SR BUILDUP SINCE I972
LAGOON
APPROXIMATE HIGH TIDE LINE 1972
DAISY - LOUJ
—
50m
FIGURE 7-22. ISOPLETHS ON FINAL ESTIMATED SURFACE TRU ACTIVITY IN pCi/g FOR ISLAND DAISY
1972 Survey Results
Soil samples were taken at eight locations on Edna during the 1972 survey; two of these were profile
samples to 35 em and the others were 0-15 cm core samples. One area of vegetation was also
sampled.
The results for 0-15 em data for 137g, 90sr and 289,240pu are summarized in Tables 7-1, 7-2, and
7-3, respectively. For all four isotopes, the activity was relatively homogeneous, both across the
surface of the island and with depth. This is probably a result of mixing and dilution from wave and
wind effects on Edna, which is frequently completely under water during tropical storms,
Surface Characterization and Fission Product Sampling
Edna is too small for IMP measurements to have been useful, so only soil samples were taken during
the cleanup.
Fifteen locations were sampled, with four composites at twelve locations and two
composites at the other three. Only surface samples were taken, so there were a total of 54
samples. (This was a modification of the usual procedure deseribed in Section 4.2.1.) No ratio of
TRU to 241 Am was estimated because there were no IMP data. Tech Notes 2.19 and 2.19A describe
the results of the soil sampling, which are also shown in Figure 7-23, along with the sampling
locations. The maximum TRU activity in any soil sample was less than 40 pCi/g, so no soil removal
was required on Edna. Table 7-5 summarizes the soil sample results of the TRU activity.
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