of the cisterns, causing an increase in the radionuclide concentration in the
cistern water.
When the Bikini
people return and live in
the houses,
the
vegetation growth around the cisterns will be eliminated, and screens can be
placed over the openings to prevent vegetation from going into the cisterns.
It is also possible to design the cisterns into the walls of the house, as was
done at Enewetak.
In either case,
the
radionuclide concentrations
in
the
cistern water ‘would be lower as a result.
ANNUAL RAINFALL
4
The annual rainfall at Bikini Atoll since 1982 is listed in Table 37.
These data have been collected continuously using tipping-bucket rain gages.
The data are collected in 20-second intervals, integrated over 20-minute time
periods, stored on magnetic tape, and transmitted to a National Weather Bureau
satellite for subsequent transmission to LLNL.
We have a continuous 5-year
record of rainfall, with a 20-minute resolution, from one station on Eneu
Island and a continuous 3-year record from two stations on Bikini Island.
The annual rainfall] has varied from a low in 1984 of about 32 inches to a
high in 1986 of about 77 inches.
The monthly 5-year-average rainfall at
Bikini Atoll] is shown in Fig. 32.
The dry season begins in December and runs
usually through April.
The rainfall increases usually in May through: August;
August and September are usually the peak months.
The significance of the
annual rainfall and the rainfall pattern will be considered in the discussion.
RESUSPENSION
We have made detailed measurements of resuspension of particulate matter
at both Bikini and Enewetak Atolls; a thorough discussion of our resuspension
studies is given in Shinn et al. (1980).
Under normal conditions, the mass
loading in the air is about 21 yg/m>? of dust and organic particles and about
34 yg/m> of salt from the continual sea spray from wave interaction on the
ocean reef.
Ouring the process of clearing vegetation and surface groundcover
by bulldozers, the mass loading from surface resuspension was 140 ug/ms,
The
cleared soil surface stabilized very rapidly over 3 to 4 days to a point where
the mass loading was essentially back to normal (see Table 38).
60