SLIDE 27
Estimated activity intake from cistern water.
radioiodine activity per unit area estimates,
activity from fallout
Based on 1) Bikini Ash
2) a 20% release of iodine
granules to cistern water and, 3) an average cistern
water volume of 0.15 m’, the radioiodine activity concentrations were
estimated for cisterns located at Rongelap Island.
These concentrations were
in agreement with gross beta analysis of cistern water.
Prior to evaculation of Rongelap, many weeks of drought were reported by
Sharp (Sh57).
In the weeks preceding the BRAVO contamination, water from
cisterns was rationed to one pint cup per person eagh day (Sh57).
Assuming
this wording implies US liquid measure, then 470 cm” of water per person per
day were distributed and regulated by village officials.
This water was used
to. make tea and coffee and was directly ingested (Sh57).
cm
of water were assumed to be taken with each meal.
One hundred fifty
At Rongelap Island,
this was assumed to occur at 5.5 (lunch), 12 (dinner), 24 (breakfast), 30
(lunch), 38 (dinner) and 50 (breakfast) hours post detonation.
These assumed cistern water intakes led us to estimate the ingested
activity tabulated here.
This was a conservative estimate of radioiodine
activity intake from this pathway because all the activity in the liquid phase
in the cistern was assumed to be due only to the iodine isotopes.
ESTIMATED ACTIVITY INTAKE FROM
CISTERN WATER
Rongelap Island
Nuclide
Activity Intake", M Bq
val
0.75
has
0.14
132!
1.0
aie
0.41
I
0.078
“Normalized to exposure rate and fallout
composition.
29