Chapter 5
HAZARDS ASSOCIATED WITH THE DOME
5.1 Function of the Dome
The function of the dome ig to prevent people from being
to harmful amounts of radioactivity from the debris buried within.
In
practical terms, the dome will perform this function if it prevegts
people from having direct physical access to the contents and if
radionuclides exchanged betwcen the contents and the environment [do not
create an unacceptable hazard.
Before addressing how well the
dome
can be expected to fulfill these goals, certain background mater
will be reviewed (sections 5.2-5.5).
5.2 Radionuclides in the Dome
The total amount of transuranics contained within the dome i
estimated to be 12.6 Ci (U.S. Gepartment of Energy 1979). Measu
of the fission product content are not available, but a crude es
of a maxiuum of 50 Ci of °"Sr and '*’Cs may be made using Atomic
Energy Commission (1973) survey data.
The average transuranic
of the material within the dome can be calculated to be about 87
pCi/g, about twice the permissible soil content of 40 pCi/g for
islands designated for residential use.
The average value measured
from the drilling samples from the dome was 21 pCi/g, but this ddes not
take account of contaminated debris that was encased in concrete fin the
center “donut hole” of the dome.
Similarly, the average total value
of **sr and '*’cs from the drilling samples was 29.3 pCi/g.
In addition, an estimated 380 Ci of activation and fission p
ucts
Plus an unknown amount of transuranics are contained in the fall
ck
debris in the true crater bottom and in the water beneath the material
in the dome (Air Force Weapons Laboratory TR-77-242 1978).
Prior
to
*Direct radiation from the contents is net of concern.
Radiation
from the fission products cannot penetrate the dome cap and have falflives of less than 30 years.
External exposures from transurani
are
not significant because the principle emissions are alpha partic
‘the external dose from the ?7*'Am gamma radiation is negligible f
the concentrations present in the dome.
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