How can I kill the bacteria in the dirt from a compost?

I have a small compost pile that was in my backyard when I bought my house, its just dirt now so I've ignored it, but my German Shepherd has recently been getting GI infections and the most likely source I can find is the compost dirt, which he loves to stand in and poke his nose into. I'm steadily removing the dirt every trash day, and I'm keeping him away from it now, but is there a simple way I can kill the bacteria in the dirt?