P- & U-Listed Wastes

P-listed and U-listed wastes are discarded commercial chemical products. The chemicals being disposed of may be unused chemicals that have spilled or been discarded because they no longer are of use. To be P- or U-listed, a waste must meet all of the following conditions:

• The waste contains one of the chemicals on the P or U list.
• The chemical in the waste is unused.
• The chemical in the waste is the form of a commercial chemical product.

In the RCRA regulations, a commercial chemical product is defined precisely as a chemical that meets all of the following criteria:

• 100 percent pure (which means the chemical is the only chemical constituent in the product)
• Technical grade (which means that the formulation, although not pure, contains a grade of purity that is in general usage)
• The sole active ingredient in a chemical formulation (which means that the chemical is the only active ingredient accomplishing the purpose of the formulation)

For example, an herbicide made for killing weeds may contain glyphosate, the active ingredient, along with inactive chemical ingredients. An inactive chemical might help the product to flow easily when sprayed, or the chemical might be a dye used to color the product. However, it is the glyphosate that accomplishes the task of killing weeds. Thus, glyphosate would be considered the sole active ingredient.

To learn more about RCRA visit our RCRA Hazardous Waste Safety Online Training web page.