Problem is that elevated nickel can mean just about anything. If it's a visual identifation instead of assay you'd suspect fairly high just to show up. If it's an assay then it could be very low. Elevated has to be compared to something. Look at Probe's recent MMI survey where they are identifying increadibly small concentrations and comparing to background stuff found almost everywhere. It's elevated but only compared to any other handful of dirt your pick up.

Sure hope elevated means greater than 1% but wouldn't bet the bank on it.