Exempt waste, determination

Exempt waste Determined on case-by-case basis No radiological restrictions... 

Waste that exceeds concentration limits for exempt waste would be classified as low-hazard if it poses no more than an acceptable (i.e., barely tolerable) risk to a hypothetical inadvertent intruder at a dedicated near-surface disposal facility for hazardous wastes, with the important condition that an acceptable risk or dose used to determine low-hazard waste should be substantially higher than a negligible risk or dose used to determine exempt waste. 

The classification system lacks a set of principles for determining when a waste contains sufficiently small amounts of radionuclides that it can be exempted from regulatory control as radioactive material. The lack of a general class of exempt waste increases in importance as the resources required for management and disposal of radioactive waste increase compared with the resources required for management and disposal of these materials as nonradioactive waste, and it may foreclose possible beneficial uses of slightly contaminated materials. 

Exempt Waste. Waste classified as exempt would be regulated as if it were nonhazardous, and would be generally acceptable for disposition as nonhazardous material (e.g., disposal in a municipal/ industrial landfill). As noted in Section 1.4.1, disposal is the only disposition of exempt materials considered in this Report. Limits on concentrations of hazardous substances in exempt waste would be derived based on an assumption that the risk or dose to a hypothetical inadvertent intruder at a disposal site should not exceed negligible levels. The use of a negligible risk or dose to determine exempt waste is based on an assumption that a disposal facility for nonhazardous waste could be released for unrestricted use by the public soon after the facility is closed. 

Disposal facilities for nonhazardous waste (e.g., municipal/indus-trial landfills) normally are constructed without substantial engineered barriers, such as a rock cover or cement waste forms, that would deter inadvertent intrusion into waste, and the waste itself often is in a readily accessible physical form. Therefore, in determining exempt waste, scenarios for inadvertent intrusion involving permanent occupancy of disposal sites and normal human activities that could access waste would be appropriate. Examples include excavation in the construction of homes and permanent residence on... 

Exposure Scenarios for Classifying Exempt Waste. Based on the definition of exempt waste as any waste that would be generally acceptable for disposal in a municipal/industrial landfill for non-hazardous waste, scenarios for inadvertent intrusion appropriate to this type of facility should be used in determining whether a waste would be classified as exempt. 

The following list provides examples of commonly exempted wastes. It is by no means comprehensive. It s up to you to make a determination on each waste stream at your site. The exemptions only apply to waste generated by E P operations. Similar wastes generated by other activities are not covered by the exemption ... 

Materials that are recycled are a special subset of the solid waste universe. When recycled, some materials are not solid wastes, and therefore not hazardous wastes, but others are solid and hazardous waste, but are subject to less-stringent regulatory controls. The level of regulation that applies to recycled materials depends on the material and the type of recycling (Figure 13.2). Because some types of recycling pose threats to human health and the environment, RCRA does not exempt all recycled materials from the definition of solid waste. As a result, the manner in which a material is recycled will determine whether or not the material is a solid waste, and therefore whether it is... 

However, there is one exception to using the TCLP to identify a waste as hazardous. The DC Circuit Court, in Association of Battery Recyclers vs. U.S. EPA, vacated the use of the TCLP to determine whether manufactured gas plant (MGP) wastes exhibit the characteristic of toxicity. As previously stated, the TCLP replicates the leaching process in municipal landfills. The court found that U.S. EPA did not produce sufficient evidence that co-disposal of MGP wastes from remediation sites with municipal solid waste (MSW) has happened or is likely to happen. On March 13, 2002, in response to the court vacatur, U.S. EPA codified language exempting MGP waste from the toxicity characteristic regulation. 

On April 8, 2003, U.S. EPA proposed to add benzene and 2-ethoxyethanol to the list of solvents whose mixtures with wastewater are exempted from the definition of hazardous waste.23 U.S. EPA is proposing to provide flexibility in the way compliance with the rule is determined by adding the option of directly measuring solvent chemical levels at the headworks of the wastewater treatment system. In addition, U.S. EPA is proposing to include scrubber waters derived from the combustion of spent solvents to the headworks exemption. Finally, U.S. EPA is finalizing the Headworks Rule, as follows24 ... 

To determine whether the character of a residue has been significantly affected by the burning or processing of hazardous waste, and thus whether the Bevill exemption can be claimed, one of two criteria must be met. As long as the residue meets either criterion, it will qualify for the Bevill exclusion. 

Management and disposal of hazardous chemical waste under RCRA is based on detailed and prescriptive technical requirements that apply to any facility for waste treatment, storage, or disposal, whereas management and disposal of low-level radioactive waste is more flexible because AEA allows consideration of waste- and site-specific factors. As a consequence, acceptable approaches to management and disposal of mixed low-level waste probably will be determined primarily by RCRA requirements, unless exempt levels of hazardous chemicals are established that render the waste nonhazardous under RCRA. 

In developing generic scenarios for inadvertent intrusion into near-surface disposal facilities used to determine limits on concentrations of hazardous substances in exempt and low-hazard waste, consideration must be given to the question of how far into the future the scenarios should be applied, as well as the earliest time at which the scenarios could occur. This issue arises because the potential risk posed by some radionuclides e.g., uranium) increases with time, due to the long-term buildup of radiologically significant decay products, and some hazardous chemicals could be transformed over time into more hazardous forms. NCRP believes that scenarios for inadvertent intrusion used to classify waste should be applied over a time period consistent with the time period for applying standards for protection of members of the public beyond the boundaries of waste disposal sites. 

In its recommendations, IAEA emphasizes that waste classification, even if it focuses on waste disposal, does not provide an adequate substitute for site-specific safety assessments of particular disposal systems to ensure the acceptability of waste disposal. IAEA also recognizes the role of national authorities in implementing waste classification systems and ensuring the safety of waste disposal, and that different countries may choose to classify waste in different ways depending on their particular situations. However, IAEA believes that, if for no other reason than to facilitate communication, it would be desirable to achieve some level of uniformity of waste classification systems in different countries. IAEA recommends that it is particularly important to obtain an international consensus on the boundary for determining unconditionally exempt material that may be transferred from one country to another, especially for purposes of recycle/reuse. 

In assessing risks based on scenarios for exposure of hypothetical inadvertent intruders at municipal/industrial landfills for non-hazardous waste (i.e., in determining whether a waste would be classified as exempt or nonexempt), scenarios involving permanent occupancy of a disposal site should be assumed to occur beginning at the time of facility closure, based on the expectation that institutional control will not be maintained over this type of facility for a significant period of time after closure. 

Use of the risk index in classifying waste is illustrated in Figure 6.2. Classification of waste essentially is a two-step process. The first step involves a determination of whether a waste can be classified as exempt, based on an assumed negligible risk and an exposure scenario for inadvertent intruders appropriate to disposal of waste in a municipal/industrial landfill for nonhazardous waste. If the waste is not exempt, the second step involves a determination of whether a waste can be classified as low-hazard, based on an assumed acceptable (barely tolerable) risk and an exposure scenario for inadvertent intruders appropriate to disposal in a dedicated nearsurface facility for hazardous wastes. 

As discussed in Sections 3.2.3, 3.3, and 6.1, RfDs and slope factors are intended to provide conservative estimates of risk. Therefore, they are most suitable for use in establishing a negligible dose, i.e., in determining whether a waste could be classified as exempt. To reduce the amount of conservatism to a degree appropriate to establishing an acceptable risk for the purpose of evaluating whether a particular waste would be classified as low-hazard or high-hazard, RfDs are multiplied by a factor of 10 and the slope factors are divided by a factor of 10. 

All waste batteries are considered RCRA solid waste except those that are returned to the manufacturer for regeneration, reused as an ingredient without reclamation, reused as a substitute, or returned as raw material. The largest percentage of disposed batteries are part of household waste and therefore exempt from regulation. The remaining waste batteries must be determined by the... 

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