Timber Preservation Chemicals Volume 1b - Field Investigations
Report No DWI0447

Oct 1988

SUMMARY

In summary the following observations can be made;

  1. undercover storage of timbers following treatment results in lower masses of preservative being leached from the timber;

  2. for CCA treated timbers, large amounts of preservative salts are leached on the first day following treatment;

  3. arsenic followed by copper precipitate out at the fastest rates in timbers treated with CCA preservative. Chromium becomes insoluble at a slower rate than arsenic or copper and is therefore leached more readily from timber over a longer period of time;

  4. phenols and PAHs are readily leached from wood treated with creosote (applied by hand) . This is especially so immediately after treatment and following heavy rainfall;

  5. heavy rainfall events cause higher masses of water-soluble preservative chemicals to be leached from timber.

Copies of this report may be available as an Acrobat pdf download under the 'Find Completed Research' heading on the DWI website.