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Categories of Waste to Consider When Determining a RCRA Recycling Exclusion From Solid Waste

Categories of Waste to Consider When Determining a RCRA Recycling Exclusion From Solid Waste

The definition of a solid waste at 40 CFR 261.2(a)(1) includes any discarded material that is not excluded from regulation by:

  • The conditional exclusions for certain solid waste at §261.4(a).
  • A variance granted under §260.30 and §260.31.
  • A non-waste determination under §260.30 and §260.34

Unless you can find an exclusion from regulation, everything you “throw away” (ie. discard) is a solid waste.  So, what then does it mean to “discard” something?

Pursuant to 40 CFR 261.2(a)(2)(i), a discarded material is anything that is:

If you generate a solid waste – and you know that you do – it may be excluded from regulation if it is recycled in a manner prescribed by USEPA regulation.  Table 1 of 40 CFR 261.2 identifies five categories of solid wastes (two categories – Sludges and By-Products – are further subdivided into two sub-categories each, making a total of seven entries in Table 1) and identifies their regulatory status (solid waste or no solid waste) based on how they are recycled.  Not included in Table 1, but essential to its complete understanding is a Co-Product, which is referenced in the explanation of a By-Product.

Categories of solid waste listed in Table 1 of 40 CFR 261.2 are…

1.  Solvents used in a degreasing operation that can no longer perform the function for which they were intended and are now Spent Materials.

A “spent material” is any material that has been used and as a result of contamination can no longer serve the purpose for which it was produced without processing;

2.  Grit, dust, and metal fines accumulated in a dust collector functioning as an air pollution control device for a metal grinding operation.


Filter cake generated at a wastewater treatment process or a drinking water filtration system.  Both are a Sludge.

Sludge means any solid, semi-solid, or liquid waste generated from a municipal, commercial, or industrial wastewater treatment plant, water supply treatment plant, or air pollution control facility exclusive of the treated effluent from a wastewater treatment plant.

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The term sludge is further divided into two sub-categories in Table 1:

  • Sludge listed in 40 CFR Part 261.31 or 261.32 (ie. a listed hazardous waste).
  • Sludges exhibiting a characteristic of hazardous waste (eg. ignitable, corrosive, toxic, reactive).

3.  Distillation or fractionation column bottoms from the production of Chlorobenzene where the column bottoms are not the primary product of the production process and typically cannot be used without further processing and are therefore a By-Product.  A By-Product differs from a Co-Product in that a Co-Product typically can be used by a final consumer without further processing.

A “by-product” is a material that is not one of the primary products of a production process and is not solely or separately produced by the production process. Examples are process residues such as slags or distillation column bottoms. The term does not include a co-product that is produced for the general public’s use and is ordinarily used in the form it is produced by the process.

Like the term sludge earlier, the term By-Product is divided into two categories in Table 1:

  • By-products listed in 40 CFR Part 261.31 or 261.32 (ie. a listed hazardous waste).
  • By-products exhibiting a characteristic of hazardous waste (eg. ignitable, corrosive, toxic, reactive).

4.  Chemicals listed by their technical name at 40 CFR 261.33 and all types of commercial products – chemical or not – if they exhibit one or more characteristics of a hazardous waste including:  scrap circuit boards, mercury thermometers, batteries, railroad ties, and more (RO 14012).  These belong to a category of solid waste referred to as Commercial Chemical Products Listed in 40 CFR 261.33.  Not clearly defined by regulation, commercial chemical products are clarified by a comment from USEPA included at 40 CFR 261.33(a):

 Comment: The phrase “commercial chemical product or manufacturing chemical intermediate having the generic name listed in . . .” refers to a chemical substance which is manufactured or formulated for commercial or manufacturing use which consists of the commercially pure grade of the chemical, any technical grades of the chemical that are produced or marketed, and all formulations in which the chemical is the sole active ingredient. It does not refer to a material, such as a manufacturing process waste, that contains any of the substances listed in paragraph (e) or (f). Where a manufacturing process waste is deemed to be a hazardous waste because it contains a substance listed in paragraph (e) or (f), such waste will be listed in either § 261.31 or § 261.32 or will be identified as a hazardous waste by the characteristics set forth in subpart C of this part.]

5.  Scrap metal is essentially a product made of metal that has become worn out or is off-specification and is recycled to recover its metal content, or metal pieces generated from machining operations and recycled to recover their metal content.  Materials not covered by this term include residues generated from smelting and refining operations (i.e., drosses, slags, and sludges), liquid wastes containing metals (i.e., spent acids, spent caustics, or other liquid wastes with metals in solution), liquid metal wastes (i.e. liquid mercury), or metal-containing wastes with a significant liquid component, such as spent batteries.

“Scrap metal” is bits and pieces of metal parts (e.g.,) bars, turnings, rods, sheets, wire) or metal pieces that may be combined together with bolts or soldering (e.g., radiators, scrap automobiles, railroad box cars), which when worn or superfluous can be recycled.

Note that the entry in Table 1 reads:  “Scrap metal that is not excluded under §261.4(a)(13)

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Once you’ve identified the category of the waste generated you may look at the recycling options identified in Table 1 as well:

And then, well…Good luck!  You’ve got your work cut out for you.  But knowing the terms used is an important first step to determining if your material is a solid waste or if, perhaps, it is excluded from regulation due to recycling.  Also, be sure to check with your state.

The best way to understand the regulations and to comply with the training requirements for hazardous waste generators is to attend one of my Training Seminars.  It’s everything you need to know about hazardous waste management and HazMat transportation in one day.