If they used Imidacloprid, perhaps the most prevalent termite poison in the world, there's good news and bad news. The bad news is it has a buried half life of up to 3 years. The good news is two fold. First, it doesn't travel well in the soil, so digging-out can help you a lot. Secondly, it breaks down into "lesser" poisonous stuff quickly in the sun. Within hours if it gets good exposure. You could do a dig-out and spread the dirt around where there's lesser chance of having meaningful contact with the poison. Like the dump or a dirt driveway.

As for the organic-ness of the site, there's a combination of functional opinions and of political ones. You won't get a clear answer but digging a lot can help. Having Hubby dig a lot can help even more!

Fanatic, call the company and find out what they used.....get the exact chemical name. Then ask about planting your grape plant; hopefully, you will get an honest answer.

Ants, even fire ants, can be controlled in a much more responsible way.

First find out what was actually spayed so you can determine what your working against.

Most synthetic insecticides can be removed from soils, with proper care, in 3 to 5 years so it could be that long before anything harvested from that grape plant could be considered organic, but it could take that long before there is any harvest.

Prepare the soil for these Muscadine grapes. Different grapes need different soil, eating grapes need soils different than do wine grapes although some soil characteristics are very similar. Muscadines prefer a soil with a slightly acidic pH, 5.8 to 6.5 range. Drainage is important, check that. how much organic matter to add depends, a goodly amount can help eliminate the insecticide but may not be good for that grape.

kimmq is kimmsr

If you really want to be an organic gardener, you might want to rethink some of the practices you engage in around the house more generally. What is Terminex spraying for? Do you actually have termites that are being treated or is this one of those (expensive) "preventative" contracts that may well be unnecessary? What are they spraying around your house? How often? Even if you have an active termite problem on your house, why are they spraying the ants out in the garden? Assuming that anything had to be done to the ants at all (a big assumption), there are options other than having a insect control company nuke 'em. You might want to ponder a bit not just about what they sprayed once in that particular hole in the past, but what they spray on your property period going forward.