Chromated copper arsenate containing hazardous materials is generated from the manufacture, treatment of the wood, and from the wood itself, after its life cycle. Laboratory treating of these wastes has resulted in materials suitable for recycle or disposal as non-hazardous residues. The extraction, by both acidic and ammoniacal routes, of CCA production and treating plant waste materials has been done. Complete extraction of the CCA components is found for strongly acidic reagents. For the ammoniacal systems with various chelating compounds, a variety of results are obtained, ranging from no extraction to nearly complete. Fixative techniques for residues generated from the production of arsenic acid were developed such that the treated wastes pass the U.S. Environmental Protection Agency's Toxic Characteristic Leaching Procedure (TCLP). The burning of CCA treated wood was also investigated. The laboratory experiments show no copper and chromium loss. Experiments with low air flows indicate conditions for which arsenic volatilization approaches zero, i.e., in excess of 1100°C. The resulting ash made of chromium, copper and arsenic compounds offers a feed stream for obtaining these materials.

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