Answer: You're right in that various insects will be found in the compost pile. They are actually doing the work of decomposing the organic matter, whether they are microorganisms that you can't see with the naked eye, or larger things, such as grubs.
Ants are excellent soil builders and although unusual in a compost pile, not harmful. It sounds as if your pile has "cooled off" or they wouldn't be there, but there's no reason to start over. If you turn the pile (which adds oxygen) and moisten everything, the decomposition process will heat up again and the ants will probably go elsewhere. Compost Happens!
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