Focus on Classification of Waste

This Report is concerned with classification of waste. However, NCRP s assumption that hazardous waste should be classified based on considerations of health risks posed by its constituents also could be used in classifying hazardous materials for such other purposes as transportation or their beneficial use in commerce. 

The waste classification system developed in this Report includes a general class of exempt waste. Waste in this class would contain sufficiently small amounts of hazardous substances that it could be managed in all respects as if it were nonhazardous (e.g., as household trash). NCRP intends that exempt materials could be used or disposed of in any manner allowed by laws and regulations addressing disposition of nonhazardous materials. However, exempt waste would not necessarily be exempt for purposes of beneficial use without further analysis of the risks associated with anticipated uses. Materials could be exempted for purposes of disposal or beneficial use based on similar considerations of acceptable risk. However, based on differences in exposure scenarios for the two dispositions, limits on the amounts of hazardous substances that could be present in exempt materials intended for beneficial use could be substantially lower than the limits for disposal as exempt waste. Thus, disposal may be the only allowable disposition for some exempt materials based on considerations of risk. In addition, some exempt materials may consist of trash, rubble, and residues from industrial processes that would have no beneficial uses and must be managed as waste. 

Based on these considerations and the purpose of this study, the recommended approach to defining an exempt class of waste that contains low levels of hazardous substances focuses on disposal as the intended disposition of exempt material. Consideration of other dispositions of exempt material e.g., recycling, reuse in commerce) is beyond the scope of this study. However, the principles used to exempt waste for purposes of disposal based on risk could be used to exempt such materials for any other purpose. 

The classification system for hazardous wastes developed in this Report is intended to be applied to waste prior to disposal. It is not 

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This Section develops NCRP s recommendations on the principles and framework for a comprehensive and risk-based hazardous waste classification system. Implementation of the system also is discussed. These recommendations focus on classification of waste that contains hazardous substances for purposes of permanent disposal. The proposed waste classification system was developed to address deficiencies in the existing waste classification systems discussed in Sections 2, 4 and 5. 

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