A public hearing was held Tuesday night on an "exploratory" well at an idled Mosaic processing plant north of Plant City. But it is unknown what exactly would eventually be sent underground.

The troubled plant in Manatee County has caused environmental problems for Tampa Bay since the 1970s. We take a tour of the site, where workers are within months of shutting it down.

Center for Biological Diversity, an environmentalist group, claims the use of phosphogypsum in the road would increase levels of radon gas, posing a cancer risk to workers and residents.