rbt
Senior Member
nfitz did bring up the possibility of gas stations. Aside from that, I think the likelihood of contamination here to be improbable and unlikely, but that's just a guess.
You would be wise to assume the opposite. A little bit of heavy metal fallout from leaded gasoline usage nearby several decades ago can be enough. 60+ years of frequent passenger aircraft flying low overhead would likely have left an impact as well.
It may not be deep but the surface layer will certainly qualify as requiring remediation.