greater than 400 pCi/g contamination levels, both in the ejecta and below the
pre-detonation surface.
Disposal would be by spreading, for levels less than
400 pCi/g, or crater containment for higher levels.
10.
The method of analysis of samples was discussed.
It was agreed that a
gross alpha count was probably the fastest and simplest method to obtain the
AAPA ee semen ee
yes-no enswer sought.
This would not define the isotopic contamination content
but would provide a base to be supplemented by radio-chemistry analysis which
would provide the isotopic content and should be correlatable to gross alpha
count for any specific area.
11.
Discussion turned to sampling increment to be utilized.
Increments
discussed included the averaged 10 centimeter depth used for most of the available
data; averaged 20 centimeter depth, based on a nominal 6-inch cut capability
for a dozer; and 20 centimeter increments with a specific 5 centimeter sample
from each increment.
The operations plan specifies 5 cm sample depth because
tn eee
past experience at Nevada Test Site has indicated that averaging samples of
greater depth leads to ancmolous data output.
will be the bases for certification of the condition of the islands upon
completicn of cleanup,
ate
Five centimeter depth samples
Discussion included the advantages and disadvantages
of horizontal averaging versus vertical averaging for sampling.
favored vertical averaging.
Consensus
Discussion also included the capability of the
laboratory to analyze the samples produced.
Maximum capability would be about
150 samples per day for gamma scan and gross alpha count plus about five percent
radiochemical analysis.
This level would not permit support of other operations.
Other operations could be supported at levels of 50 samples per day input.
It
was agreed that gamma scan of samples at the laboratory could be used to select
samples for analysis.
Only the "hot" samples would be analyzed.
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Other