54+
beef and sea foods.
HW-80991
This total body exposure may be compared with the
FRC guide of 170 mrems for the average of suitable sample of an exposed
population. Exposure from natural background sources in this region is
estimated at about 150 mrems per year (excluded from the FRC guide).
IV.
CONCLUSIONS
Comprehensive environmental surveillance of the Hanford environs
during 1963 showed that the amounts of radioactive materials present were
well within nationally accepted limits at all times and, thus, that the releases of radioactive wastes were adequately controlled.
The most significant source of exposure from the Hanford plants continued to be the p*2 released to the Columbia River inthe reactor effluent
and subsequently concentrated by local fish.
Individuals who ate such fish
as a major part of their diet throughout the year and who also ate large quantities of produce grown on farmsirrigated with Columbia River water could
conceivably have taken in as much as 50% of the annual permissible amount
of bone-seeking radionuclides.
One unusual release ofI 131 occurred from one of the separations
plants in September.
Extensive surveillance at the time showed that the tem-
porary increase in the yist content of milk and other foods did not substan-
tially alter the annual radiation dose to thyroids of people living in the vicinity
of the plant.
More gr from world-wide fallout was noted in 1963 than in
1962 and consequently the exposure from this source was slightly higher.
V.
ACKNOWLEDGEMENTS
The cooperation of many General Electric Company personnel who
collected samples, performed the many tedious radioassays, prepared and
provided data and reviewed this documentis gratefully acknowledged. °
The cooperation and contributions of the several City, State and Fed-
eral Agencies listed below is gratefully acknowledged.
Kennewick Water Department
Kennewick, Washington