Here's Memphis Commercial Appeal coverage of the Toyota decision to build a new assembly plant in Mississippi. Not much mention of clean air as a determinant. Note that Toyota is contributing $50 million (not receiving) for workforce training in schools. And I note this passage, for whatever it may be worth:
"There was a lot of tough competition," said Ray Tanguay, executive vice president of Toyota Motor Engineering and Manufacturing North America Inc. "This (site) was best because manufacturing is about systems and people.
"We have Toyota production systems and we need people that are very compatible with the 'Toyota Way' and Toyota production systems and we found Mississippi to be our No. 1 choice."
The "Toyota Way" refers to the company's pursuit of constant improvement through experimentation, employee empowerment and analysis.
Toyota officials were not convinced northern Mississippi was the ideal site on their first visit, but on subsequent visits, they determined that the area's workforce was "educated, ethical and friendly."
Tanguay said the jobs can pay about $20 per hour plus benefits.