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HW-80991
The thyroid dose shown in Table VII for Pasco residents includes an
increment accrued from fission products released by an unusually severe
failure of a fuel element in one of the reactors that occurred on May 12,
1963.
Fuel element failures are not unusual but the quantities of fission products
released to the river from them is ordinarily small.
During 1963, only the
one on May 12 released enough fission products to warrant special evaiuation.
For estimating thyroid dose,
a small child was considered to have consumed
1 liter of water from the Pasco supply during the time when the maximum
concentration of 33! was present.
The resulting dose to the child's thyroid
would have been approximately 8 mrems.
This would have increased his dose
from about 6% of the FRC Radiation Protection Guide for an exposed population
group to about 8%.
Phe) to the GI tract, bone and total body from this
incident was negligible.
The relative contribution of several radionuclides in the Pasco and
Richland sanitary water to the calculated annual dose to the GI tract is shown
in Figure 7.
Short-term variations and long-term trends in the GI tract dose
at Pasco are shown in Figure 8.
The dose received by the GI tract of Pasco residents continued at about
the same level as experienced in 1962.
water for reduction of As 5, Np239 ,
1963.
Treatment of the reactor cooling
and other nuclides was continued during
This modification consisted mainly of increased addition of alum in the
clarifying process which reduced the amount of parent materials from which
As’ 6
C.
and Np
239
are formed.
Radionuclides in Fish and Waterfowl
Fish and waterfowl that feed in the Columbia River downstream from
the reactors acquire some radionuclides that enter the river with the reactor
effluent water.
The concentration of several radionuclides in the flesh of
different kinds of fish from several locations on the river are reported in
Appendix A, Table 10.
Except for suckers, whitefish usually contain the
greatest concentration of radioactive rnaterials and pe? is the radionuclide
of greatest significance.
The concentrations of p?? in whitefish caught