HPA is exclusive to Cap-chat as was mentioned...don't remember exactly where I read it.
My idea is
The main mission for Veolia is to get rid of Red MUd by treating and presume these eventual plants will be startegically located in countries where bauxite is processed and stockpiled and the subsequent output sold back to third parties or the smelters.
I see this as having the same type of logistics that recyclers of used tires, glass and plastics or paper have where the recyclers, such as metals have to pay something for the raw material.
I have no idea why anyone would want to pay for RED MUD other than to take care of the transportation to get it to the plant for processing but who knows depending on the output expected.
That's just my guess on how this might work out.