Your situation will be a good test of the E-Trac's ability to handle iron and still find coins. What you are calling reo we call rebar here in the states. First switching to ironmask and raising the level will only make the detector null more. What I would try would be hunting in the Jewelry Mode and if anything lowering the Sensitivity a little. We have heard from people and seen videos of how the E-Trac can detect coins when they are surrounded by iron and I have found coins when they are above the iron. So since the iron you are talking about will be off to the side of the coil I would think that even though the E_Trac is nulling it should still be able to detect coins and jewelry until you get close to the wall where the iron may just overwhelm the machine. It should be a good test to see how close you can hunt to that wall and still find targets. JMHO
HH
Beachcomber