There should be no rebar anywhere near the plaster layer. They should have seen this after the gunnite went in. I would think that they will have to chisel out that area, grind down the rebar then patch and reapply plaster and pebble. You cannot have exposed rebar in a pool. The chemicals will eat away at it. Rust is just the first sign of that.

..Doyle

I had a friend have something similar happen....only it wasnt rebar, but a nail. How did the nail get in there, who knows....must have happened in the pebble process. The pebble tec company came back and repaired the spot. Hopefully, your problem is an easy fix.

Of course it can be rust and rebar related. Rust spots will brush off and then come back in a few days. It is quite a normal process. The fact that it is there is not normal. It is most likely a tie wire on the rebar that did not get cut. Almost impossible to see unless to have a good QC guy prior to plaster. Many pools are plastered with exposed rebar. They simply paint it and plaster over it. The result is a piece of steel only an inch or two below the surface and if there is an imperfection in the surface, which pebble tec can easily have, you can get a spot.

Yes, nails are all over the pool in construction. Concrete nails are used to secure bender board for tile and coping installation. Could be that too. If it's a tie wire, and you catch it early, it will not hit your rebar, but once it does, it will start corrosion there and it can get ugly.

Have the plaster company check it out. They can usually chip it out and patch.

repair_guy - There is no tie wire poking through, just rebar.

Thanks everyone. I'll definitely be calling the pool builder and have it taken care of. I just hope they can patch it without it looking different from the rest of the pool.

How much would a repair job for exposed rebar be? The pool is one and a half years old.