This is a nightmare scenario in a permissive environment. The safety of the workers is imperative. Building an incinerator would be the best thing to do. That’d cost over a billion dollars. Ideally, this will someday be done, but that should happen in a reasonably benign environment if there is any hope of these chemicals being completely destroyed.
I’m not going to hold my breath until any WMD gets destroyed. If anything does, it will be for show, IMO, to be “in compliance” with some agreement.