Fifty-two CCA treated poles removed from service after 1 - 50 years were sampled at different depths from their below ground and above ground zones and the preservative levels and mass balances related to the location in the pole and pole age. Generally CCA retentions were still well above the toxic threshold for decay in even the oldest poles. This confirms the good leach resistance of CCA and that surface remedial treatments may not be necessary for CCA treated poles and that round wood products made from CCA treated poles removed from service may be re-used without the need for re-treatment. Comparisons of CCA retentions and mass balances above and below ground show that some poles have high copper leaching from the below ground area, probably as a result of wet sites and some arsenic leaching occurs from all depths in the poles. The significant disproportioning effect, whereby chromium is concentrated on the surface relative to copper and arsenic must be considered when using mass balances to infer differential leaching of CCA components.

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