Legal Question in Real Estate Law in California

What is the issue you are having? Did the seller fail to disclose this, if so when and how did you find out? Is there a health hazard that requires remediation (fixing)?

It depends on the exact problem. Former meth labs usually involve CERCLA clean ups.

You might want to have at least an initial conference with someone who specializes in criminal defense. I assume you aren't accused of anything and therefore don't need criminal defense per se, but the gouys and gals that do criminal defense work would probably be most familiar with the issues likely involved here. Based on my three years' experience in a county public defender's office, I'd say that more than 50% of criminal defense involves illegal drugs in some way or another, so these folks have plenty of experience in that area.