onceapilot (#21),
..."From what little I know, huge amounts of CW were dumped at sea around UK"...
Dumped the remaining stocks of mustard (in 65lb cans) from CDRE Cannanore around March 1946 myself. Position: roughly 20 mi out to sea from W coast of India, about 11 degrees N latitude.
Vengeance could carry 4 tins per trip (2 tins per 500lb bombrack) internally (could not use 250lb wing racks as tins too flimsy). Dropped on ranges would burst on impact. We also had spray tanks which were carried on the wing racks, but the filling them from the cans was too nasty and dangerous a job to ask the armourers to do when it was not "operationally" required.
Tanks were cleaned out and used later for anti-malarial DDT spraying experiments.
Danny.