8

100 0 200400
foO

Pacific ocean

Fig.

7.

Meters

<A map of Bikini Island showing specific areas of interest for the
dose calculations.
Existing houses are situated within area l.
Areas 2 and 3 are proposed village sites for future housing units.

The interior portion of the island is denoted by area 4.

the radioactivity from those
islands.

Since the islanders spend a

Gamma exposure rate data

considerable fraction of their time

reported by Bennett and Beck, > He1d,°

in the immediate vicinity of their

Lynch etal.,’ Gustafson, ° Smith and

homes, it may be feasible to take

Moore,” and Robison et a.?° were

certain remedial actions

used for this purpose.

the exposure rates in this area.

Their

to reduce

results, in conjunction with a

For instance, placing 5 cm of clean

simplified area weighting scheme,

coral gravel around the houses out

yielded the values presented in

to a distance of 10 m, a common

Table 3.

practice in the Marshall Islands,

Note that these are rough

estimates since the data are scarce

will reduce the exposure rates by a

and were collected over a span of

factor of two.

almost 10 years.

with clean soil the top 20 cm of soil

The exposure rate

Removing and replacing

over the lagoon was estimated to be

out to a distance of 10 m from the

3.3 uR/h due to the cosmic ray

houses will reduce the exposure

contribution and an additional 0.2

rates by a factor of eight.

uR/h due to naturally occurring

addition, the shielding provided by

radionuclides in the sea water.

the houses themselves will reduce the

-18-

In

Select target paragraph3