CCA wood remains hot topic.The fate of scrap wood treated with chromated copper arsenate Chromated copper arsenate (CCA) is a wood preservative used for timber treatment, in use since the mid-1930's. It is a mix of copper, chromium, and arsenic formulated as oxides or salts. (CCA (1) (Common Cryptographic Architecture) Cryptography software from IBM for MVS and DOS applications. (2) (Compatible Communications A ) in Florida is being debated by the state's Department of Environmental Protection (DEP DEP Deposit DEP Deputy DEP Department of Environmental Protection DEP Dependent DEP Departure DEP Depot DEP Deposition DEP deployed (US DoD) DEP Data Execution Prevention (computer security) ). The agency is currently asking the recycling and solid waste industries to suggest best management practices to separate the CCA-laced material from the rest of the C&D stream. A November meeting in Orlando between the DEP, academic researchers and representatives from the recycling and solid waste industries yielded the call for information. The DEP's intention is to develop the best management practices, evaluate alternatives for the identification of CCA wood and determine the options for and the issues of handling CCA wood after it is separated from the solid waste stream. Because its semi-tropical climate requires significant pest control measures, Florida may have more CCA-treated wood than any other state. A study headed by Helena Solo-Gabriel of the University of Miami This article is about the university in Coral Gables, Florida. For the university in Oxford, Ohio, see Miami University. The University of Miami (also known as Miami of Florida,[2] UM,[3] or just The U reports that currently about 5 million cubic feet of CCA wood is disposed of annually in the Sunshine State. Additionally, her study shows that between now and 2024 a steep rise in disposal is forecasted to occur, perhaps to as much as 30 million cubic feet annually. DEP information shows that currently some of this material is making it into unlined landfills; some goes into lined landfills; and some makes it into C&D recycling centers. Unlined landfills can leach the CCA, the DEP says, while C&D recycling centers can contaminate con·tam·i·nate v. 1. To make impure or unclean by contact or mixture. 2. To expose to or permeate with radioactivity. con·tam·i·nant n. products such as colored mulch and boiler fuel with CCA wood, though they strive to keep the material out of infeed stocks. Attendees at the November meeting noted difficulty identifying CCA-treated wood. Especially if weathered, it looks remarkably similar to non-treated wood. Technology is available to detect CCA wood, but most or all have serious drawbacks, says William Turley, executive director of the Construction Materials Recycling Association (CMRA CMRA Commercial Mail Receiving Agency CMRA Construction Materials Recycling Association CMRA Central Motorcycle Roadracing Association CMRA Capital Market Risk Advisors, Inc. ), Lisle, III. For example, Turley notes, a chemical stain put on all the incoming wood can tell which is CCA tainted, but this is a labor-intensive process that does not sort material as it identifies it. Mechanical systems that detect and sort out CCA wood use X-rays or lasers to detect the contaminant contaminant /con·tam·i·nant/ (kon-tam´in-int) something that causes contamination. contaminant something that causes contamination. and then rely on mechanical sorting to jettison jettison (jĕt`əsən, –zən) [O.Fr.,=throwing], in maritime law, casting all or part of a ship's cargo overboard to lighten the vessel or to meet some danger, such as fire. the offending pieces. These systems show promise, says Turley, but require very cost-prohibitive capital investments. Neither method has proven itself yet in a high-production setting, he adds. |
|
||||||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion