I had two 5 gallon buckets I used to grow eggplant and pepper last season. I just got them up from the basement to amend the soil and put eggplant seedlings in. One of the bucket has depleted soil and a lot of what I think are millipedes. What should I do with it now? do I have to dump the soil? Are they harmful to the plants. Can I just scoop out some soil and hope not all of the five gallon is infested?
Photo attached so that somebody can confirm those are millipedes.

Both the buckets were next to each other, but only one has the infestation. This one had another small planter upside down in it was the only difference.

As I recall, millipedes eat other insects, so no they are not harmful to the plants. Beneficial, in fact. Still, I'd refresh that soil before planting your new plants, adding at least half new potting soil to the mix. A healthy population of millipedes might mean there's somebody else living in there as well. Otherwise what have they been feeding on?

Or, you could dump those containers into your new raised bed, and start completely fresh.

It depends on the species. I know a few species are omnivorous and some are even carnivorous. They feed on insects, earthworms, snails, centipedes, etc. Some species have mouth parts that allow them to feed on plant juices.

But are they millipedes?
Yesterday's heavy rain or the sun before that seems to have killed them all. Well at least they are not moving anymore. sigh.

Those are millipedes. Millipedes feed mostly on decaying matter, but as Tee said some feed on other things.

Thank you. I dumped some soil out. Refreshed it and planted eggplants. My outdoor planting season begins