What lies beneath?

We finally moved, and the adjustment was seamless for all of us. Except the dog. He’s a freak. Wouldn’t walk in the kitchen or foyer. Won’t run through his new, giant back yard. My spouse wonders what he senses…Radon seeping upstairs from the basement? Toxic waste in our groundwater from the gas station ¾ of a mile away? Me? I’m thinking ghosts.