Terrible noxious smell in Northwest Columbus

Hey y'all, last year or so there was a post about a strange chemical smell that would come every morning. There were lots of theories as to who was off gasing the chemicals, and I know a lot of people contacted the EPA, myself include. It seemed to go away for awhile but know I feel like it is back and even worse. Any thoughts on where it is coming from? One theory was as asphalt plant, and when the EPA checked it out they found it was "clean." After the EPA visited the smell did seem to decrease. Maybe we need to re mobilize and get them back on the case? The air is unbreathable.