Update from your link:
UPDATE @ 7:58PM:
Dale Petry, the emergency services director for Kanawha County, says emergency response teams are setting up at different places around the county to monitor the haze & smell. He’s hoping special equipment on the response trucks will be able to help identify what is causing it.
Petry also confirms that county emergency officials went up in a helicopter Friday with DEP officials to see if the source of the haze cand be pinpointed — but they didn’t find anything conclusive.
According to Petry, firefighters went to chemical plants in the valley and set up monitoring systems — and no traces of any leaks were detected.
Right now: Petry says there is almost no wind, causing the cloud to stay put. He adds, though, that it is moving north slightly toward Sissonville.
Initially it was reported that the local emergency administrator was fuming with anger that Bayer had not reported the extent of a Thiodicarb leak. It was reported that firemen had spray 1 ‘barrel’ of leaking Thiodicarb, then it was revealed that at least 3 ‘barrels’ had released Thiodicarb.
Then this story was removed, and no record of it is available to my search.
Here is haz mat info on Thiodicarb....pretty nasty?
http://www.agrian.com/pdfs/Larvin_Brand_32_Thiodicarb_InsecticideOvicide_(52201)_Label.pdf