I actually am trying to research what has happened to clean things up in Trona. I'm pretty sure the smelting plant there is as productive as ever. They just are able to employ far fewer people due to technology. I'm guessing it's a mix of newer high-tech smokestack scrubbers, an EPA crackdown and even Erin Brockovich. She won a massive lawsuit in a desert town not too far from Trona and I think she also took on Kerr-McGee's Trona plant. But again, I need to do some more research. But looking back, it was insane running a mile at race pace in stinky dirty air that you could cut with a knife. Good times.