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Frequent Questions about the Identification of Non-hazardous Secondary Materials that are Solid Wastes

On this page: 

  1. What are the main differences between the proposed and final rule?
  2. What does EPA consider to be a non-hazardous secondary material?
  3. Why is EPA differentiating which non-hazardous secondary materials are or are not solid wastes under RCRA?
  4. Does the final rule address whether secondary materials are or are not a solid waste for other non-combustion types of end use (for example, applying materials to the land as a fertilizer)?
  5. What were the key factors the Agency considered in determining whether a non-hazardous secondary material is or is not a solid waste?
  6. What are examples of non-hazardous secondary materials that EPA considers solid waste when burned in combustion units?
  7. What are examples of non-hazardous secondary materials that EPA considers not to be solid waste when burned in combustion units?
  8. Why did EPA decide to regulate the burning of whole tires under CAA section 112?
  9. Do resonated wood residuals have to be processed before it is used as a fuel outside the control of the generator?
  10. How does EPA determine whether abandoned coal refuse has been processed enough to be equal to current standards?
  11. Is manure determined to be a solid waste when burned in combustion units?
  12. How are space heaters that burn used oil addressed by today’s rules?
  13. What difference does it make whether a non-hazardous secondary material is burned in a combustion unit that is subject to the CAA section 129 standards as opposed to CAA section 112 standards?
  14. How will this decision affect Environmental Justice communities?
  15. Is there a process for requesting from EPA a case-specific determination with respect to whether or not a specific non-hazardous secondary material is a solid waste?
  16. Some commenters have argued that any secondary material that is burned for energy recovery is a solid waste. Has EPA considered this alternative, and if so, why is EPA not including that approach in the final rule?

 What are the main differences between the proposed and final rule?

This rule is being issued in conjunction with three Clean Air Act (CAA) rules. The rule identifies under the Resource Conservation and Recovery Act (RCRA), which non-hazardous secondary materials when used in a combustion unit are or are not solid wastes. The major differences between the proposed rule and today’s final rule are:

What was in the proposed rule? What changed in the final rule?
Scrap tires were considered to be solid waste when combusted unless they were sufficiently processed into a non-waste fuel product. Scrap tires are also a non-waste fuel if removed from vehicles and managed under the oversight of established tire collection programs
Resinated wood residuals are a solid waste if transferred off-site to someone else. Material is a non-waste fuel if burned in a combustion unit within the control of the generator. Resinated wood residuals burned in a combustion unit (whether within the control of the generator or outside the control of the generator) would not be a solid waste, provided the legitimacy criteria are met.
Coal refuse that has been abandoned and then processed, even if such processing was the same as the way coal is processed today, was considered a solid waste. Abandoned coal refuse that is processed the same way as coal is today to lower contaminants and increase energy value is considered a non-waste fuel.
Traditional fuels were defined as historically managed fuels, such as coal, oil, natural gas, and their derivatives, and clean cellulosic biomass. In addition to historically managed traditional fuels, added an “alternative fuels” category to the definition of traditional fuels. Examples include coal refuse, on-spec used oil, and clean cellulosic biomass. The new definition clarifies that “traditional fuels” are not secondary materials and are not solid wastes unless “discarded.”

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What does EPA consider to be a non-hazardous secondary material?

Non-hazardous secondary materials are any materials that are not the primary product of a manufacturing or commercial process, and can include post-consumer material, post-industrial material, and scrap. Many types of these materials have British Thermal Unit (BTU) or material value, and can be reclaimed or reused in industrial processes.

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Why is EPA differentiating which non-hazardous secondary materials are or are not solid wastes under RCRA?

A wide and diverse range of non-hazardous secondary materials exists and we know that some percentage of the approximately 200,000 boilers or industrial furnaces use these secondary materials as a substitute for primary fuels or as ingredients. Previously, EPA promulgated a rule pursuant to CAA section 129 that excluded units used to recover energy for a useful purpose from the definition of solid waste incinerator, and instead these units were subject to the applicable CAA section 112 requirements. This rule was subject to judicial challenge and vacated by the U.S. Court of Appeals for the District of Columbia. In its decision, the court stated that the CAA requires any unit that burns "any solid waste material at all," regardless of whether the material is being burned as fuel, to be regulated under CAA section 129 as a "solid waste incineration unit.Thus, in response to the court's decision, EPA is issuing criteria which identify those non-hazardous secondary materials used as fuel or ingredients in combustion units, such that:

  • Units that burn non-hazardous secondary materials that are solid waste under RCRA would be subject to the section 129 CAA requirements
  • Units that burn non-hazardous secondary materials that are not solid waste under RCRA would be subject to the section 112 CAA requirements

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Does the final rule address whether secondary materials are or are not a solid waste for other non-combustion types of end uses (for example, applying materials to the land as a fertilizer)?

No. In the final rule, EPA is identifying which non-hazardous secondary materials are solid wastes under RCRA Subtitle D when combusted so that EPA can establish appropriate standards under CAA sections 112 and 129. The final rule does not address the question of which non-hazardous secondary materials are or are not solid wastes in any other beneficial use or recycling situation (for example, land application). States fully implement the RCRA Subtitle D program and have promulgated their own laws and regulations regarding what constitutes a solid waste, some within established beneficial use programs. EPA will continue to look to the states to make these determinations.

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What were the key factors the Agency considered in determining whether a non-hazardous secondary material is or is not a solid waste?

The key factors the Agency considered are:

  1. Whether the material has been discarded—that is, whether it has been abandoned, disposed of, or thrown away, and
  2. If material has been discarded, whether it has been sufficiently processed to produce a new non-waste fuel or ingredient product—sufficiently processed means operations that transform discarded non-hazardous secondary materials into a legitimate non-waste fuel or ingredient, including operations that: remove or destroy contaminants, significantly improve the fuel characteristics of the material, e.g., sizing or drying the material in combination with other operations, chemically improve the as-fired energy content, and improve the ingredient characteristics. Minimal operations, such as operations that result only in modifying the size of the material by shredding, would not be considered processing under this rule.

In addition, to ensure that non-hazardous secondary materials that are burned in a combustion unit are done so legitimately—that is actually used as a fuel or ingredient and not a sham, the Agency has developed legitimacy criteria. Specifically, for non-hazardous secondary materials used as a fuel, the legitimacy criteria are that the secondary material must:

  1. Be managed as a valuable commodity;
  2. Have meaningful heating value and be burned in units that recover energy; and
  3. Contain contaminants that are comparable to or lower than in traditional fuel products

For non-hazardous secondary materials used as an ingredient, the legitimacy criteria are that the secondary material must:

  1. Be managed as a valuable commodity;
  2. Provide a useful contribution;
  3. Be used to make a valuable product; and
  4. Contain contaminants that are comparable to or lower than in traditional products.

Secondary materials burned in combustion units that do not satisfy these legitimacy criteria would be considered a solid waste.

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What are examples of non-hazardous secondary materials that EPA considers solid waste when burned in combustion units?

Under the final rule, examples of non-hazardous secondary materials designated as solid wastes when burned include:

  • Whole scrap tires from waste tire piles;
  • Off-specification used oil;
  • Sewage/wastewater treatment sludge;
  • Contaminated construction and demolition material;
  • Chromate copper arsenate treated wood.

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What are examples of non-hazardous secondary materials that EPA considers not to be solid waste when burned in combustion units?

Under the final rule, examples of secondary materials designated not to be solid wastes (if they meet the legitimacy criteria) when burned in combustion units include:

Clean biofuels/biogas processed from solid waste;
Scrap tires removed from vehicles and managed under established tire collection programs and tire-derived fuel from the processing of scrap tires removed from tire piles (shredded with the steel belts and wire have been removed);
Materials, such as cement kiln dust, coal ash, and foundry sand that are used as ingredients in manufacturing processes (e.g., in cement kilns).

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Why did EPA decide to regulate the burning of whole tires under CAA section 112?

In determining whether or not a non-hazardous secondary material is or is not a solid waste, including scrap tires, the primary issue is whether or not the material has been “discarded.” We have concluded that scrap tires that are removed from vehicles and managed under established tire collection programs have not been discarded and thus, are a non-waste fuel and can be combusted in units meeting the CAA section 112 standards. The Agency has determined that these programs ensure that scrap tires are not discarded en route to the combustor for use as a fuel and are handled as a valuable commodity as required under the legitimacy criteria. As under the proposed rule, whole tires retrieved from waste tire piles clearly have been discarded, and thus, must still be sufficiently processed in order to be combusted as a non-waste fuel.

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Do resonated wood residuals have to be processed before it is used as a fuel outside the control of the generator?

No. Resinated wood residuals do not have to be processed before it is used as a non-waste fuel outside the control of the generator. Information has been provided that demonstrates that the transfer of this secondary material outside the control of the generator would not constitute discard and is used as either “furnish” (i.e., raw materials) or fuel at the receiving facilities. This material when transferred outside the control of the generator is used and handled in the same manner that resinated wood residuals are used when generated within the control of the generator, such that it is impossible to distinguish between materials that are being used as a raw material and those that are being used as a fuel.

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How does EPA determine whether abandoned coal refuse has been processed enough to be equal to current standards?

Coal refuse is distinctive from the other non-hazardous secondary materials in today’s rule, as it is raw material coal (even if it has been previously been abandoned) generated as a result of coal mining operations whose primary product is a fuel. Thus, to the extent that this coal refuse is processed the same as coal is today, we believe that level of processing is sufficient. This processing comprises of grizzlies, screens and blending to improve quality, removal of metal objects, reduction of ash and sulfur content, and the concentration of various constituents, serving to both increase its energy value, as well as reduce the level of contaminants in coal refuse, (Prior to such processing, the coal refuse that has been abandoned is a solid waste and would be subject to appropriate federal, state and local laws and regulations).

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Is manure determined to be a solid waste when burned in combustion units?

Upon reviewing the comments and data received, we conclude, in general, that animal manure that is used as a fuel “as generated” does not satisfy the legitimacy criteria, and thus is a solid waste. However, there are circumstances where manure would not be considered a solid waste when burned as a fuel for energy recovery. For example, manure that has been “sufficiently processed” to produce a legitimate non-waste fuel and meets the legitimacy criteria would not be considered a solid waste when burned as a fuel, In addition, we recognize that manure can have other beneficial uses and emphasize that we are not making a solid waste determination on those other uses through this rulemaking.

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How are space heaters that burn used oil addressed by today’s rules?

Today’s final rules do not impact the regulation of used oil burned in space heaters. Specifically, EPA is clarifying that regulation of used oil combusted in oil fired space heaters that meets the provisions of 40 CFR 279.23 would not in any way change the current regulatory scheme or operations for burning of used oil in space heaters. This includes used oil generated by small facilities, such as auto repair shops and machine shops that have such units, and used oil generated by homeowners who change their own oil (referred to as “do-it-yourself” or “DIY” oil) that are burned in such units. This is because the CISWI regulations promulgated under the Clean Air Act do not establish emissions limits for such units.

We would also note that data provided in the comments to the proposed rule indicates that a very small portion of used oil is off-spec. Assuming the data is representative of used oil, most used oil will be an alternative fuel (within the definition of traditional fuel), including used oil obtained from small, private automobiles serviced by “do-it-yourselfers” and auto repair shops.

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What difference does it make whether a non-hazardous secondary material is burned in a combustion unit that is subject to the CAA section 129 standards as opposed to CAA section 112 standards?

To learn about the different requirements of Clean Air Act section 112 and Clean Air Act section 129, please visit Basic Information about Emissions Standards for Boilers and Process Heaters and Commercial / Industrial Solid Waste Incinerators.

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How will this decision affect Environmental Justice communities?

EPA has determined that the final rule will not have a disproportionately high and adverse human health or environmental effects on minority or low income populations because emissions reductions from facilities burning such non-hazardous secondary materials are expected to be significantly reduced, such that the populations near these facilities are expected to experience reduced incidence of adverse health effects. EPA’s environmental justice analysis is described in the document, Summary of Environmental Justice Impacts for the Non-Hazardous Secondary Material (NHSM) Rule, the 2010 Commercial and Industrial Solid Waste Incinerator (CISWI) Standards, the 2010 Major Source Boiler NESHAP, and the 2010 Area Source Boiler NESHAP.EPA will continue to work with state and local environmental agencies and Environmental Justice communities on how the rule will be implemented in those communities.

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Is there a process for requesting from EPA a case-specific determination with respect to whether or not a specific non-hazardous secondary material is a solid waste?

Yes. The final rule establishes a non-waste determination petition process that provides a formal mechanism by which a person can petition EPA that a non-hazardous secondary material that has been transferred to a third party, has not been discarded and is indistinguishable in all relevant aspects from a product fuel is not a solid waste. Any petition that is submitted to EPA that requests that the non-hazardous secondary material be considered a non-waste would need to describe how the secondary material satisfies the legitimacy criteria discussed in Question 5. The non-waste determinations will be further based on the following five criteria:

  1. Whether market participants treat the non-hazardous secondary material as a fuel rather than a waste;
  2. Whether the chemical and physical identity of the non-hazardous secondary material is comparable to commercial fuel;
  3. Whether the capacity of the market would use the non-hazardous secondary material in a reasonable time frame;
  4. Whether the constituents in the non-hazardous secondary material are released to the air, water or land from the point of generation to just prior to the point of combustion of the secondary material at levels comparable to what would otherwise be released from traditional fuels; and
  5. Other relevant factors that demonstrate the non-hazardous secondary material is not discarded.

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Some commenters have argued that any secondary material that is burned for energy recovery is a solid waste. Has EPA considered this alternative, and if so, why is EPA not including that approach in the final rule?

It is EPA’s judgment that this approach would go beyond EPA’s authority under RCRA in defining “solid waste” in light of the RCRA case law. Specifically, the RCRA definition of solid waste does not extend to secondary materials beneficially used in a continuous industrial process, as that material has not been discarded and is not a solid waste.

EPA also considered in the proposed rule a different alternative option which is broader than the proposed solid waste definition that EPA believed could be constructed in a manner consistent with RCRA and relevant case law. Under this alternative, traditional fuels that have been burned historically as fuels and managed as valuable products would not be solid wastes. In addition, non-hazardous secondary materials used as fuels or ingredients would not be solid wastes when burned in a combustion unit if they both remain within the control of the generator and meet the legitimacy criteria. However, all materials that are derived from processing of discarded non-hazardous secondary materials would be considered solid wastes, as would all materials that are burned in a combustion unit that are not under the control of the generator. Also, no petition process was offered under this alternative.

Comments were specifically requested on the alternative option related to the potential impact this alternative may have on traditional non-combustion recycling activities, potential changes in the quantity of secondary materials that may be landfilled, and any collateral regulatory impacts, such as the impact on the MACT floors proposed in the Commercial and Industrial Solid Waste Incinerators rule if a significant number of additional sources are subject to that rule. No public comments were received that favored this alternative approach.

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