If your not using CCA lumber the problems from leaching are near zero. Almost all leaching occurs from surface or near surface residue and early on. After the initial period very little occurs. Hose off your wood in the driveway and let air dry before using and you'll remove most. After air dry some seal before construction and apply another quick coat after. Others just seal after finished.
Plus the impact of newer preservatives are very little compared to treated lumbers of past
Your from CA with strict wood regulations and it won't be a problem but rotting out prematurely in a wet environment will be.
Last edited by batman; 10-07-2020 at 08:19 AM.
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