Yeah I'm aware they do, but it's outdated, inaccessible, and lacking, which is why I guess I want to do a better job at it, and ideally host many more sensors.
I live on the southern shoreline of Lake Michigan, the rest of Gary, Whiting, Hammond is directly south of the Gary Works, BP, etc. There should be way more hyper-localised air quality monitoring, 1-2 isn't enough, the air I breathe, isn't what school kids in Gary/Whiting breathe.
https://www.epa.gov/outdoor-air-quality-data/interactive-map...
(from there, click through to the map and then turn on layers of interest)