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Hazardous Waste

Memorandum about Treatment of Underlying Hazardous Constituents in Toxicity Characteristic Metal Wastes

This memorandum discusses the treatment of underlying hazardous constituents (UHCs) in toxicity characteristic metal wastes or those with waste codes D004-D011. EPA’s review of the treatment data on toxicity characteristic (TC) metal and mineral processing wastes shows that universal treatment standards (UTS) are achievable for the UHCs in TC metal wastes (including mineral processing wastes).

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