Ours was back filled and dewatered so chipping it out would be risky as well. We measured after it was shot because I wasn't sure how concrete thickness would vary etc. I dot want a free deck just maybe at cost. I just really notice the off measurements and the bubbler isn't at the furthest point of shelf. It's about 2.5 feet off, what do you guys suggest we do? I don't want to be greedy but this really is bothering us. What would be reasonable to ask for off etc. I really don't feel this Is at all our fault I went over these plans with pb about centering quite a few times. With fencing rebar pumps I wasn't sure measuring would reflect the same measurement afte being shot.