Sooo much!Here are the stats for cleared UXO in 2019, only for North-Rhine Westphalia, the state were i (and von Marwitz) live.
Bombs (all kinds): 2.160 pcs., Weight: approx 80 tons, thereof approx. 38 tons explosives.
Grenades: 11.061 pcs, Weight: approx 30 tons, thereof approx. 2.5 tons explosives.
Mines: 29 pcs., Weight. approx. 150 kg, thereof approx. 90 kg explosives.
Handgrenades: 689 pcs., Weight: approx 0.6 tons, thereof approx 0.2 tons explosives.
Other explosives, small arms ammunition etc.: Not counted, Weight: approx. 12 tons, thereof approx 0.9 tons explosives.
656 UXOs had to be detonated in the place where they were found, because they couldn´t be defused or the transport would have been too dangerous.
It is quite a lot taking into account that munitions are not systematically searched for.Sooo much!