Classification and Characterization of Hazardous, Radioactive, and Mixed Wastes - Stabilization and Solidification of Hazardous, Radioactive, and Mixed Wastes - page 43

TABLE 3.5
Radionuclides and Concentrations for LLW
Classification (2)

Concentration (Ci/m 3 )
Column 1 Radionuclide Column 2 Column 3

Total of all nuclides with less
than 5-year half-life

700 (*) (*)

H-3 40 (*) (*)

Co-60 700 (*) (*)

Ni-63 3.5 70 700

Ni-63 in activated metal 35 700 7000

Sr-90 0.04 150 7000

Cs-137 1 44 4600

Source: 10 CFR 61.55
* = There are no limits established for these radionuclides in Class B or C
wastes. Practical considerations such as the effects of external radiation
and internal heat generation on transportation, handling, and disposal will
limit the concentrations for these wastes. These wastes shall be Class B
unless the concentrations of other nuclides in Table 3.2 determine the waste
is Class C independent of these nuclides.

in Table 3.5, the waste shall be Class C, provided the concentration of nuclides listed
in Table 3.5 does not exceed the value shown in Column 3 of Table 3.5.

3.3.2 R ADIOACTIVE W ASTE C HARACTERIZATION

The definition of Radioactive Waste Characterization can be described as the deter-
mination of the radiological, chemical, and physical properties of the waste to
establish the need for further adjustment, treatment, conditioning, or its suitability
for further handling, processing, storage, or disposal.
Radiological waste characterization involves detecting the presence of individual
radionuclides and quantifying their inventories in the waste. This detection and
inventory can be done by a variety of techniques, depending on the waste form,
radionuclides involved, and level of detail required. For instance, a simple radiation
dose rate measurement will give an indication of the total quantity of gamma-
emitting radionuclides in a waste package, but will not identify individual radionu-
clides or their concentrations. Gamma spectroscopy will identify the individual
radionuclides and their quantities as well. Other techniques, such as active or passive
neutron interrogation, alpha spectroscopy, and liquid scintillation counting, are used
for other classes of radionuclides. The preferred methods are often referred to as
“nondestructive” or “noninvasive,” since they do not involve opening a waste package
to take samples. The terms most frequently used are NDA (nondestructive assay),
NDE (nondestructive examination), and NDT (nondestructive testing).