Source: https://www.mccoyseminars.com/newsletter/article.cfm?artnum=201
Timestamp: 2019-04-24 23:45:45+00:00

Document:
Scrap tantalum anodes, wire, pellets, and pins meet the definition of “scrap metal” found at §261.1(c)(6). (Tantalum is a highly corrosion-resistant transition metal that is widely used as a component in metal alloys.) Thus, if these materials are legitimately recycled (i.e., meeting the factors in §260.43), they are exempt from RCRA hazardous waste regulation under §261.6(a)(3)(ii), even if they exhibit a characteristic or have become contaminated with a listed waste.
Tantalum powders would meet the definition of scrap metal in §261.1(c)(6) only if they are agglomerated in such a way that the agglomerated material physically resembles other types of scrap metal (i.e., bits and pieces of metal parts). For example, tantalum powder that has been mixed with a binder and then sintered at high temperature to cause the particles to form a structure of high mechanical strength and density would meet the definition of “fines, drosses and related materials which have been agglomerated” and would therefore be considered “processed scrap metal” per §261.1(c)(10). Per §261.4(a)(13), “processed scrap metal” is excluded from the definition of solid waste if legitimately recycled (i.e., meeting the factors in §260.43).
Non-agglomerated tantalum powders would not meet the definition of scrap metal in §261.1(c)(6). Thus, non-agglomerated tantalum powders that exhibit a hazardous waste characteristic per Part 261, Subpart C would be considered a hazardous waste, even when sent for recycling.

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