If you're really worried, moving it is the only real solution.
You COULD spray the ground between the wood stack and the house, but ants and termites will likely tunnel anyway, so that won't really help much. This is why termite control injects the ground around the building foundation because bugs don't usually like light so they tunnel or even BUILD tunnels (termites do this).
Looks like you're in for some sweat soon.
Depending on how big the gap is between the house and stack, you COULD go to a home improvement store and get the "do it yourself termite kit" and apply as directed.
18.5", 22.5" OTS
Large BGE (chambersuac's)
The Fiery Furnace (chambersuac's)
Big JT's Smokin' BBQ Competition Team