My dad was in hazardous waste abatement (see: US Superfund cleanups), and I talked to a guy at a corp party years ago who was researching plants growing on slag. But he was looking at the plants that were sucking up the abundant toxins present in slag with an eye towards environmental cleanup (slowly). Slag is often very nasty stuff, and certain plants (no, I don't know which) were really good at sucking up and sequestering the nastiness.

I've driven past some of those areas on the way home from Chicago. I just assumed they were swaps that hadn't been drained for some reason. It's interesting to know that they were once dumps for the millions of tons of slag that got produced along with the steel the region is known for.

The Calumet region has it's share of environmental dumpster fires. In fact, there were areas in East Chicago, Indiana (which doesn't actually border Chicago, btw) where the topsoil was 0.1% lead.

Growing up, my neighbor told me of his youth near the refineries in Whiting when he and his friends hit the GASOLINE Table digging a hole in back yard, which was used for fueling cars until Standard Oil found out about it, and bought up the neighborhood.

I'm a proud Region Rat.

all that to say: “Nature, uh, finds a way."