I suspect ROI will be negative (especially given sky-high cost of US infrastructure projects) - lead is safe if not consumed inside. And AFAIK it happens mostly

I suspect ROI will be negative (especially given sky-high cost of US infrastructure projects) - lead is safe if not consumed inside. And AFAIK it happens mostly in two situations - old chipping paint and lead pipes. Even chipping paint should be a problem either when paint dust is everywhere or when children are playing with paint chips. Lead pipes are more dangerous and should be replaced but even lead pipes leak significant lead amounts only if pH is high (or water flow is high). In comments to this thread I see what looks to me like a moral panic - people leaving in safe conditions are full of fear (and who are really unsafe are not represented on HN). Lead is not something which can kill you at a distance, or if you consume 1 μg of it.