Hope somebody can help me! I have a lot of air in my water lines. (I have a well with submersible pump). The house is a slab. I thought my pressure tank was bad. But, it is o.k. A plumber came out and said I have a leak in the water line somewhere from the well to the house. He said to dig down to the level of the pitless adapter by the well. I did. No leak there. Then I dug down to where the black pipe goes into the foundation of the house. It was a little muddy, but didn't find the leak. It seems to be coming from under the house! . There are no wet areas (on the ground)from the well to the house. So, I'm thinking the leak is probably under the house. What should I do next???