"Galvanised" - or to be more correct- zink plated steel is not very welcome in the average steel killn, only a certain amount can be added to the mixture if at all. The problem is of two natures: first the oxidation is hindered due to the zink cover (scrap mills prefer the rusty quality) and secondly there are more and tighter emission laws limiting the zink fumes which are extreme toxic. Welding a piece of zink coated steel demands a good mechanical ventilation, many workshops simply won't touch the job. But left in peace it's considered harmless, steel pipes designed to transport drinking water are equipped with it.
Here in Cork I know of two county council yards where these barriers are simply dumped/dugged in.The reward for the scrap doesn't seem to be very atractive, not even the travellers (who are frequently engaged in the scrap metall trade) camping next to one site I know seem to be interested in it.