I heard in one documentary following the defusing/safe detonation of one of these that the "KBD" (one of the shorthands for the civilian ordinance disposal services) is estimated to have to work in this field for at least several decades considering the (potential) amount of explosives still hidden in the ground and water. Especially the water is another hot topic since after WW2 the Allies just dumped huge amounts of explosive ordinance and chemical weapons into the North and Baltic Seas which are slowly corroding under the water and releasing their toxic innards into the ecosystem(s).
A bunch of people employed by the ordinance disposal service have died doing their work over the years (relevant portion cited):
"Despite a professional and extremely cautious approach, deadly accidents caused by uncontrolled explosions occur time and again when defusing bombs. In the years 2000 to 2010, eight explosive ordnance clearance personnel were killed in action, [11] three of them alone in the detonation of a 500 kg Allied bomb on June 2, 2010 in Göttingen." -- https://de-m-wikipedia-org.translate.goog/wiki/Kampfmittelr%...