In this study, laboratory long-term leaching studies were conducted to characterize the leaching behavior of arsenic, chromium, and copper from CCA-treated wood samples (block, chip, and sawdust) and CCA-wood ash and to determine the rate of release of the metals from the CCA wood products. The leaching solutions were periodically collected and analyzed for the concentrations of arsenic, chromium, and copper. Results of the leaching studies showed that the flux rates of arsenic from CCA-treated wood samples were consistently much higher than those of chromium and copper throughout the 60-day leaching period. Increased leaching time significantly reduced leaching rates of all CCA elements. The particle size of CCA-treated wood used also affected the leaching rates of the elements. Relatively large surface area unit weight of CCA-treated wood allowed more wood available for leaching. In case of CCA wood ash, the rate of chromium release from CCA wood ash specimens was much greater than that of arsenic for the first 12 h flux. However, the steady-state release rate of arsenic from the ash was greater than that of chromium. Much of the chromium was present in the hexavalent form, which is more toxic and mobile than trivalent chromium

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