A requirement of a generator’s hazardous waste determination is to determine if their waste is listed at 40 CFR 261, Subpart D.  The four lists that make up the hazardous waste listing are:

• F-List for generic industrial sources.
• K-List for specific industrial processes.
• P or U-List for unprocessed commercial chemical products.

Any solid waste that isn’t excluded elsewhere and matches the description of a hazardous waste listing is a hazardous waste and subject to full regulation under RCRA.

The US EPA uses three (3) different criteria to determine whether or not to include a process or chemical in one of the four hazardous waste listings, the three criteria are:

1. The waste typically contains toxic chemicals at levels that could pose a threat to human health and the environment if improperly managed.  If this criteria is the basis for listing a waste it is assigned a hazard code of T for Toxic Waste.
2. The waste contains such dangerous chemicals that it could pose a threat to human health and the environment even when properly managed.  These wastes are fatal to humans and animals in low doses.  If this criteria is the basis for listing a waste it is assigned a hazard code of A for Acute Hazardous Waste.
3. The waste typically exhibits one of the four characteristics of hazardous waste:  Ignitability, Corrosivity, Reactivity, Toxicity.  If this criteria is the basis for listing a waste it is assigned a hazard code according to its characteristic:  Ignitable Waste (I), Corrosive Waste (C), Reactive Waste (R), Toxicity Characteristic Waste (E).

Note the following:

• The reference to “hazard code” should not be confused with “hazardous waste codes”.  The “hazard code” is an indication of the US EPA’s reasoning for listing the waste.  A “hazardous waste code” is assigned to all wastes determined to be hazardous (either characteristic or listed).
• A Toxic Waste (T) differs from a Toxicity Characteristic Waste (E).  The Toxic Waste meets the first of the three criteria, that is it typically contains toxic chemicals that could pose a threat if improperly managed.  The Toxicity Characteristic Waste exhibits the characteristic for Toxicity which is a basis for listing a waste identified in the third criteria.
• The four characteristics of hazardous waste – Ignitable, Corrosive, Reactive, & Toxic – are described in §261, Subpart C.
• A waste that is determined to be a listed hazardous waste solely because it exhibits one or more characteristics of Ignitability, Corrosivity, or Reactivity is known as an ICR-Only Listed Waste.
• There are 29 ICR-Only Listed Wastes:

• A waste that matches the description of an ICR-Only Listed Waste is not assigned the listed hazardous waste code if it does not exhibit the applicable hazardous waste characteristic at the point of generation.  Example:  Spent acetone used as a solvent matches the listing description for F003 (non-halogenated spent solvent).  F003 has a Hazard Code of I for the characteristic of Ignitability.  If the spent solvent does not exhibit the characteristic of Ignitability at the point of generation, then the F003 hazardous waste code would not apply.
• Additionally, if an ICR-Only Listed Waste is mixed with a solid waste the resulting mixture does not retain the listed hazardous waste code if the mixture does not exhibit the applicable hazardous waste characteristic [40 CFR 261.3(g)(2)(i)].  Example:  Spent acetone used as a solvent matches the listing description for F003 (non-halogenated spent solvent).  F003 has a Hazard Code of I for the characteristic of Ignitability.  If the spent solvent is mixed with a non-hazardous waste so that the resulting mixture does not exhibit the characteristic of Ignitability, then the F003 hazardous waste code would not apply.
• Read more about F-Listed Spent Solvents.

The fact that an ICR-Only Listed Waste retains its listed hazardous waste code only if the applicable characteristic hazardous waste is exhibited may play a crucial role in your hazardous waste determination.  This then will impact your hazardous waste generator status and all subsequent regulations with which you must comply.  Make certain you have conducted the hazardous waste determination correctly and documented the outcome.  As always check with your state regulatory agency on issues such as these and please don’t hesitate to contact me with any questions.