mr fish (#28),
..."question...how is mustard gas safely disposed of?"...
In wartime, the advice was to "wash off at once with copious quantities of water" (a drop of liquid mustard, left on the skin for 20 mins, will inflict a third degree burn).
On that basis, dumping at sea is the best way, as it will quickly dilute into harmlessness. So that is what I did.
We knew nothing about nerve agents - somebody else here may have an idea.
Danny.