A sure way to deter termites or carpenter ants is to use Taurus SC , which the active incredient is fipronil. There's also a product called Termidor that is also fipronil but higher priced. There's also lower priced fipronil under the brand name of Combat, but its 1% fipronil. Taurus and Termidor are 9% fipronil and this is the strength used by exterminators, which can be purchased by us consumers.
I had a carpenter ant infestation in my wood pile. And even though it was 60 foot from the house, they spread to my house. I talked to an exterminator and he told me he would use Taurus SC. I had been using a bait called Optigard, which would've eventually eliminated the ant colony, but Taurus SC got rid of them immediately.
Taurus is not cheap, something like $50 for a 12 oz bottle. But it does not take much and is very effective. Its a bait that the ants/termites carry back to the colony and spreads it to the queens and male workers. Most baits are gels. This one being a spray can cover a lot more space. It works.
After treating my house ( there's a lot of YT vids on how to use termidor to treat your house ) I took it to my wood pile. I put my wood up on blocks, just as you've done, but before putting wood on the rack I sprayed the ground below the rack and the rack with Taurus. I then put my smoker wood on the rack. It got rid of the carpenter ants without spraying my smoker wood.
I also had termites in the area of my wood pile and I've not seen any trace of them since spraying with Taurus.
Actually, carpenter ants and other wood boring bugs, are helpful to seasoning the wood and don't really do any harm to the wood for smoking purposes. But the problem is they will spread to the house. In the spring, when the weather is right which is low wind and the right temperature, some of the queens of a carpenter ant colony will leave and fly off to start a new colony elsewhere. I watched this happen with the colony in my house. They can easily spread from a wood pile to the house.