The fixation of CCA-C preservative was investigated in red maple sawdust (Acer rubrum L.) at target retentions of 4.0, 6.4, 9.6 and 30.0 kg/m3. The effect of water-soluble extractives on the course of fixation was evaluated comparing the non-extracted with pre-extracted samples treated to 6.4 and 30 kg/m3. Leaching of the CCA components was monitored after complete fixation for all retentions. Fixation results show rapid chromium reduction, with the formation of a significant amount of water-soluble chromium complexes at lower retentions. Copper fixation was extremely fast while a substantial amount of arsenic remained unreacted. Leaching at the lower retentions was characterized by exceptionally high losses of arsenic and moderate losses of copper and chromium. Increase in the strength of the CCA solution consistently improved fixation and leaching of CCA in red maple. The observed anomalies were more pronounced for low retention levels. The presence of water-soluble low molecular weight carbohydrates, phenolic, and other extractives is likely the prominent factor responsible for the observed irregularities.

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