This study evaluates the copper (Cu), chromium (Cr) and arsenic (As) removal from CCA treated wood using boron compounds such as boric acid, borax (sodium tetraborate), and Timbor (DOT, disodium octaborate tetrahydrate) at varying (3 and 5%) concentrations. Remediation processes were taken at 1, 5 and 10 day intervals. Metals in remediated chips or sawdust were then analyzed using ICP and XRF. Results showed that, higher level of Cu was removed followed by As and Cr. The percentage removal of metals was higher in saw dust then chips. Borax at lower concentration (3%) removed 41.4%, 18.3% and 44.9% of Cu, Cr and As, respectively, in 10 days while at higher concentration (5%) 65.8%, 55% and 55.8% of Cu, Cr, As, respectively, were removed for the same period. Boric acid removed 39.7%, 15.5% and 35.6% at lower and 50.7%, 48.9% and 50.9% of Cu, Cr, and As at higher concentration, respectively, while DOT was not an effective extractant. Distilled water extraction removed 27.3%, 23.7% and 22.8% of Cu, Cr and As respectively. In case of chips, borax removed 30.3%, 19.7% and 24.9% of Cu, Cr, and As; boric acid removed 25.5%, 12.2% and 19.5%; DOT removed 22.8%, 10.8%, 14.2% and distilled water 17.7%, 11.1% and 10.2% of Cu, Cr, and As, respectively. Increasing the concentration of solution has greater effect on elements removal. Among the three compounds tested, borax removed higher levels of metals compared to boric acid and DOT.

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