Discussion of Example Analyses

The example analyses for electric arc furnace dust in Section 7.1.7 and a hazardous chemical waste in Section 7.1.8 lead to an important conclusion about these particular wastes. The concentrations of heavy metals, especially lead, in the electric arc furnace waste clearly are sufficiently high that long-term exposure to the waste by an inadvertent intruder may need to be precluded in order to ensure that deterministic effects would not occur. In addition, for either waste, the stochastic risk that could result from unrestricted release of a disposal site might exceed acceptable levels, due to the concentrations of heavy metals that induce stochastic effects. Both of these factors indicate that these wastes may be classifiable as low-hazard only if perpetual control would be maintained over near-surface disposal sites to prevent long-term exposures of inadvertent intruders. Such a conclusion also was obtained in the example of uranium mill tailings discussed in Section 7.1.5. 

It is not NCRP s intent to develop specific recommendations concerning classification of wastes based on the example analyses discussed in Sections 7.1.3 through 7.1.8. This is especially the case when wastes contain high concentrations of heavy metals (NCRP 

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