I would personally just leave the area as a giant nature reserve (including the Zone of Obligatory Resettlement). We have more than enough high quality arable land.
I visited the zone back in 2007. It was pretty clear that on some level, nature was doing very well in the zone. We saw deer in Pripyat and large groups of wild horses on the meadows.
https://www.unep.org/news-and-stories/story/how-chernobyl-has-become-unexpected-haven-wildlife
Not to mention there will always be a level of stigma with produce from the zone (including the Zone of Obligatory Resettlement).