Like busy moles, we humans dig an awful lot of holes to get things done, in the ground, in our oceans, and even in our bathrooms! We dig holes in sandboxes to play games with friends, on ancient sites to discover awesome treasure and fossils, and on farms to plant the food we eat. Unfortunately, we also dig holes that aren't so wholesome--holes that rip apart the ground, spill dangerous chemicals, and permanently damage the earth. Going on this way...