I believe with proper documentation remediation is tax deductible in that you can raise your cost basis when you sell.

Further, your mortgage interest up to $750K is also tax deductible, and you have to index the whole thing to inflation. Once you do all that the costs are either nominal or negative on a 3.5% 30 year fixed deducted from a Bay Area income. Until Donny took us for a ride property taxes were deductible too.

This is what it looks like when owners vote.