Another interesting finding from MS-2 was that the estimate of Pu mound +
desert pavement inventory at Area 13 was somewhat lower than the 46 + 9
curies reported by Gilbert (1977b)
for just surface soil at Area 13.
("Surface soil" excluded the interior of mounds below 5-cm depth.
portion of the mound was included, however,
in MS-2.)
Gilbert and
This
Essington (1977) discuss the possibility that the differences in estimates
are due to sampling variability arising from the skewed nature of Pu
soil concentrations, particularly near ground zero.
Much of our analyses of these mound data were accomplished during 1977
after the March, 1977, NAEG Pu Information Conference.
The statistical
analyses of these data are now essentially complete.
While inventory
estimates meet certain DOE requirements, we feel that particle-size
studies at different depths of mounds would provide urgently needed
information on potential hazards to man from inhalation or ingestion of
Pu particles, if future mound studies are performed.
CLEANUP STUDIES
Initial Efforts
Sampling studies dealing with possible cleanup efforts at NTS and/or TTR
study sites have been under discussion by NAEG scientists for several
years.
Wallace and Romey (1975) presented cleanup procedures and
experience gained at a number of locations and gave an extensive reference list.
A companion reference is that of Rhoads (1976), who gives a
position paper on treatment of certain Pu-contaminated areas on NTS.
Gilbert and Eberhardt (1976b) mention some planning needs for cleanup
experiments, and Wallace and Romney (1977b) discuss what is known thus
far on initial land reclamation procedures following a possible Pucleanup activity at TTR.
Some possible approaches to the statistical
analyses of data for deciding whether some type of cleanup or other
remedial action is required at a particular site are considered by
Gilbert and Eberhardt (1977) and Gilbert* (1977a).
The design of sampling
plans for cleanup purposes is discussed briefly by Eberhardt and Gilbert
(1972).
Wide-ranging discussions on the design of cleanup treatment and trial
experiments were conducted at NAEG meetings in Boulder City, Nevada, in
March, 1975, and at Battelle-Northwest Laboratories in Richland, Washington, in October,
1975.
The design of cleanup sampling plans was discussed
*Work funded by Division of Biomedical and Environmental Research,
Department of Energy.
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