The effect of water-repellent additives on the leaching of CCA from simulated southern Yellow pine decks
F Cui, P J Walcheski
End-matched SYP boards were pressure-treated with CCA or CCA in combination with commercial water repellent additives. After fixation and drying, the boards were placed in plastic boxes and exposed outside in Harrisburg, NC. Plastic supports were used to keep the boards above the water collected. Over a period of five months, rain run-off water from 14 natural rainfalls were collected and analyzed by ICP. Metal leachate level was related to the type and level of water repellent additive present. Two commercial water repellents, which had much better water repellency than the third product, were found to be effective in reducing CCA leaching. Arsenic leaching can be reduced by over 35% in the presence of 1.2% of the two effective water repellents.
Keywords: CCA; LEACHING; WATER REPELLENT; WATER REPELLENCY