06 04 Metal-containing wastes other than those mentioned in subcategory 06 03

Electroplating processes, the production of electronic components and chemical catalysts, pigment manufacturing, and other industrial operations generate hazardous residues classified under code 06 04 05* Waste containing other heavy metals, i.e. neither arsenic nor mercury.

This category includes sludge from electroplating wastewater treatment facilities, filter residues, spent solutions, and solid process residues containing metals such as cadmium, lead, copper, nickel, zinc, or chromium. As these compounds are highly toxic and capable of accumulating in living organisms, they pose a serious threat to natural ecosystems.

Environmentally responsible management of such waste requires compliance with strict industrial safety regulations, as heavy metals do not decompose naturally and, in the event of an uncontrolled release, can leach into soils and contaminate groundwater.

They must never be mixed with ordinary waste, discharged into open water bodies or municipal sewage systems, or left in open areas without protection from precipitation. Businesses are required to arrange sealed temporary storage in specially designed acid-resistant or otherwise protected containers, with continuous monitoring, and to transfer these hazardous materials exclusively to licensed operators.

The most appropriate approach to managing this waste is the recovery and reclamation of valuable components using hydrometallurgical or pyrometallurgical technologies, allowing the metals to be returned to the production cycle as part of a circular economy.

Where this is economically or technically unfeasible, the waste undergoes deep chemical stabilization processes (immobilization or cementation) to prevent the migration of toxic elements.