If you have a compost heap then it is safe to reuse it there. Vine weevil grubs are an issue in pots as there are no predators, it is warm and loose and can generally feast off of the plant roots with abandon and I have had plants wit literally no roots left. In the ground it is cooler, more predators and they tend to nibble on a few plant roots - so are less of a problem, so you can put the soil into a border if you pick out the grubs and pour over boiling water first.

The birds love the grubs if you can be bothered to put them on the bird feeder.