Thanks for the comments, I feel a little better. I didn't notice the super wide ledge until it was really too late... they put up the wires right before they shot it. I was thinking that the inside of the vault would be much bigger. They told me it needed to be 13" to force the cover to roll up tighter. I'm not sure if they left room for the plaster or if they plaster inside the vault. It's definitely too rough as is. I don't believe they intended the ledge to be that large, just the rebar guy set it up wrong. I think worst case the ledge will have to stick out under the vault covers. The ledge is 17" wide with 32" and 10" extra on the ends of the vault. They put the edge of the ledge at the water line and said the tiles/plaster will raise it to 1" above the water line.
bmoreswim... it is the reallly expensive one.. at least to me. It is the latest from coverpools with stainless steel cables instead of ropes. Do you loose much water over the dam? 1' doesn't seem like a lot. I'm guessing i'll have an exposed ledge... unless they can cover 31" I'm guessing that with plaster it will be 18" so 3 tiles wide. I'm not sure how stable the lids are anyway so it might not be bad to have a 10 or 12" lege for the kids to sit on. (might be a slip hazard)
Trvbm.... thanks for the pic, I had only seen small ledges online so far. The shotcrete is sloped down away from the water... may be a difference in brands. They did mention trying to get 'edge' style tiles, but i like the bullnose that you have. It is plumbed with a "side" drain and we didn't get the leaf catch... figured we wouldn't need it with the cover. I read many forum issues with the leaf catcher and the release pumps so we didn't get those.
In my favor they ended up making the free standing wall 14" thick to hide the end of the vault sticking out of the exposed wall.