[2021] Tailings question

Wet Tailings stay wet and should be dealt with like other tailings. In the future they'll need to be contained in leak-proof pits, like with clay, but that is not the case yet. Slag should only pollute minorly.

I don't have the exact values available, but yes, Slag should be minorly polluting like garbage and hence more than normal building blocks. Trample isn't pollution, by the way, just - trample.

The minor pollution is not on asphalt using treated and recycled slag, but on pure slag itself
(and thats what I understood AnLambdy to want to use) that still contains minorly damaging substances. I don't know how stuff in Houston works, I'm from far over the pond - but here slag is treated before such usage. Asphalt is not polluting in the game.