RONGELAP REASSESSMENT
This reassessment
visit to Rongelap.
is prompted by information obtained during a February 1986
Considerable
quantities of “Yap variety” coconuts are being
grown on Rongelap even though the majority of the coconuts on the island appear
to be of the “old variety.”
Why is this a concern?
1.
The reasons are the following:
The external gamma exposure and the soil concentration
of 137CS is
higher by about a factor of 2 at Rongelap than at Eneu.
Decay corrected
to 1987
Soil 137Cs Concentration
External Gamma
pCi/g
r/h
0.5cm
O-40cm
12
4.1
Rongelap
4.5
Eneu
2.3
5.9
2.9
ratio
2
2.0
1.4
2.
The 137CS concentration
“
in coconut meat and fluid, however,
15 pCi/g wet weight at Eneu and about 5.5 pCi/gwet
The ratio of the 137CS concentration
is about
weight at Rongelap.
in coconut on Rongelap to that
on Eneu is thus about 0.4.
3.
This difference was assumed to be due to the two different varieties
of coconuts on the island; i.e., “Old Variety” on Rongelap and “Yap
Variety” on Eneu.
Age of the trees and 137CS distribution
soil column could not be discounted,
4.
however.
.
This result has been confirmed by evaluating both varieties
that are near neighbors at Eneu and Bikini Islands.
effect of age cannot be discounted
in the
of trees
However, the
in this observed difference.
19
.