East Palestine, Ohio, is not the same place it was a year ago. Last February, a Norfolk Southern train carrying hazardous materials derailed there, near the Pennsylvania border, close to people's homes and businesses. Then, a few days later, 900,000 lbs of vinyl chloride was intentionally vented from 5 railcars and burned, leading to an explosion and a dark plume seen for miles around.

Over the next three weeks, we'll explore what happened and what the fallout has been for residents. First, we hear from a mother who evacuated the town with her son, who was experiencing horrific symptoms, and why they haven't gone back. We examine the decision by health officials not to test residents for chemical exposure. We'll also hear from a researcher who thinks environmental regulators were too hasty in their assessment that the town was safe. And finally, we visit businesses trying to keep their shops open, some more successfully than others.