Copper, Chromium, and Arsenic in Estuarine Sediments Adjacent to Wood Treated with Chromated-Copper-Arsenate (CCA)

Sediments adjacent to and at varying distances from bulkheads made of wood treated with chromated copper arsenate (CCA) were analysed for content of these three elements. Sediments immediately adjacent to the bulkheads had very low percentages of the fine-grained particle fraction (silts and clays), but very high concentrations of the three metals associated with the fine particles. Copper was always much higher than chromium or arsenic. Sediments further away from the bulkheads had higher percentages of silts and clays with lower concentrations of the three contaminants in this fraction. This indicates that Cu, Cr, and As leached from the wooden structures can be accumulated in fine-grained sediments nearby. Higher metal concentrations were retained in sediments in poorly flushed areas than in more open water environments. The highest concentrations were found adjacent to the newest bulkhead.