variations in radiation levels,

little can be said about the

characteristics of areas where high or low levels might be
found.

Field gamma spectral measurements, at two locations
(see Figure 6) are summarized below.

SPECTROMETER AND IONIZATION CHAMBER EXPOSURE RATES

(ur/hr )

Total

Location

187 a5

$°Co

*25 co,

Total

.4(10%)

4.0

4.1

. 3 (6%)

4.8

5.1

Aircraft hangar

3.1(78%)

-5(12%)

1200

3.0 (63%)

1.5 (31%)

ft.

north

exposure

rate

The exposure rates at these two locations were representative

of the average levels of radiation for the island.
The radioisotopes, which were present, were in proportions similar to

locations on Bikini, though in much less quantity with the

major contributor to the total dose rate still **°’cs (60 to
80%) .

With the HASL TLD units placed on Eneu, we obtained
exposure rate estimates consistent with the other measurements.
At four locations along the lagoon road, the TLD results were

6.7 ur/hr, 4.6 pr/hr,

13.2 ur/hr, and 5.7 wr/hr.

The NRDL

TLD measurements did not show non-zero readings due probably
to the larger uncertainty in the background subtraction.
No soil samples were taken on Eneu in 1967 due to the

very low gamma radiation levels which are in the range of

the natural exposure rates commonly found in the Continental
uU. s.7'?,
However, the 1964 soil data confirm that 187 ag
is the major contributor to the total exposure rate.

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