Table 7.3. Classification based on long-lived radionuclides

DOE-STD-6003-96

TABLE 7.3. Classification based on long-lived radionuclides

Concentration (Ci/m3)

Radionuclide

Column 1

Column 2

Column 3

Total of all nuclides with

700

<5 yr half-life

H-3

Co-60

700

Ni-63

3.5

700

Ni-63 in activated metal

700

7000

Sr-90

0.04

150

7000

Cs-137

4600

aThere

are no limits established for these radionuclides in Class B or C wastes. Practical con-

siderations such as the effects of external radiation and internal heat generation on trans-

portation, handling, and disposal will limit the concentration for these wastes. These wastes

will be Class B unless the concentrations of other nuclides in Table 7.3 determine the waste

to be Class C independent of these nuclides.

If the concentration does not exceed the value in Column 1, the waste is Class A. If the

concentration exceeds the value in Column 1, but does not exceed the value in Column 2, the

waste is Class B. If the concentration exceeds the value in Column 2, but does not exceed the

value in Column 3, the waste is Class C. If the concentration exceeds the value in Column 3, the

waste is not generally acceptable for near-surface disposal.

Again, the limits for mixtures of nuclides are listed in Table 7.3; the total concentration

shall be determined by the sum-of-fractions rule.

No limits are specifically given for heat generation with a waste package, aside from the

requirement that the package must be shown to be capable of removing the decay heat.

7.4.2 Methodology of 10 CFR 61 Extended to Fusion-Specific Isotopes

10 CFR 61 gives specific activity limits for only a dozen radionuclides, many of which are

fission products or transuranics and thus of little relevance in fusion materials selection. Fetter et

al. have used the NRC's intruder scenario to calculate Class C limits for other long-lived

radionuclides (Fetter 1988). The specific activity limits in Table 7.4 are those for Class C waste

that is activated metal. The limits in Table 7.4 should be compared with those in column 3 of

Table 7.3. Differences between Tables 7.3 and 7.4 result from (a) the fact that the waste is

assumed to be an activated metal and (b) corrections made to the dose conversion factors

made by Fetter et al. Footnotes to the table indicate specific activity limits derived by other

authors.

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