My version of Atlanta basically had them scrapping the ground free of all fallout and planting on the now 2-inch lower ground. Mostly they used plants that were rad-resistant, but they also planted perennials grown in a grow house in clean soil.

I was thinking about Hiroshima and Nagasaki when I wrote it. You can actually live there now, but cancer and birth defects, etc are far more common than the rest of Japan.