Interim Baseline Radiological Investigation Report
November 14, 2012
Bear Lodge Project, for Rare Element Resources, Ltd.
Rev.1
26
Table 4.5. Statistical Summary of Radium-226 Concentrations Predicted from Gamma
Count Rates
Estimator/Endpoint
Radium-226, predicted
(pCi/g)
a
Mean (arithmetic)
1.9
Standard Deviation
1.1
Median
1.6
1
st
quartile
1.3
3
rd
quartile
2.2
IQR
0.9
Minimum
0.6
Maximum
20.1
Count (n)
141,958
Notes:
a
Measurements only within the Project.
IQR = interquartile range
The median of the predicted concentrations of Ra-226 is 1.6 pCi/g and IQR is 0.9 pCi/g (2.2 less
1.3 pCi/g). The median of the predicted concentration of Ra-226 is in good agreement with the
median of the laboratory results. This indicates that gamma surveys are an effective tool to
predict Ra-226 concentrations in soil at the Project.
