A huge effort went into finding wartime (and post-war) nasties all over the UK in the late 1990s, led by the now defunct RAF Infrastructure Orgnisation. Old, and allegedly clean, sites were reopened and remediated at considerable cost. Where is the corporate knowledge management?
I had great delight, on being invited to visit Chimark during the remediation phase (site of 14 MU), going to Clothing Stores and drawing a 'proper' NBC suite and requesting 'war use' cannisters and not training ones. Up until the early 1990s, the management of munitions at that site was remarkably lax (especially around the proofing house) and at the end of the war, the Mustard Pots were simply filled with chlorine bleach, and then all sorts of other material was simply dumped in with it. Chlorine, of course, can also be a war gas...