Dirk Schoenen moves slowly down into the darkness. The silence is compact. The only thing that can be heard is his own compressed breaths through the diving helmet.
On the muddy bottom off the German Boltenhagen lies a giant pile of scrap, writes the news agency AP, which has visited the area. Dirk Schoenen carefully lifts the top pieces and puts them in a basket: shotgun cartridges, grenade fragments, projectiles. It is a precision work performed with triple layers of diving gloves. The skin must not come into contact with the crumbling ammunition.
From a platform on the surface, a group of engineers and sailors follow every move carefully via a camera on Schoenen's helmet. The work is not risk-free. Mines and undetonated bombs become more sensitive over time and can – in the worst case – explode.
This is not routine work. The challenge is, of course, that you never know what you find, says 60-year-old volunteer Schoenen, who has been diving since 1986, to AP when he is winched up after an hour's work.
Dumped for payment
At the same time as tensions in the Baltic Sea region are growing again, with almost daily incidents between Russia and NATO's allies, Germany is still struggling to clean up after World War II. The government in Berlin has allocated 100 million euros to projects that will study how the seas can be cleared of war debris.
The work may seem futile. Remaining on the bottom is around 1.6 million tons of old ammunition, according to the German Environment Ministry. Most of it was deliberately sunk after World War II, as the Allies were concerned that the Germans would resume arms production at some point. In 1946, trains were sent from all over Germany to the coast, and for payment, fishermen drove out the scrap and dumped it in the sea.
The project off Boltenhagen began this summer. Only in this area, around six kilometers north of the white beaches of the resort, a field with around 900 tons of ammunition has been discovered.
Global problem
Here, two diving teams work in 12-hour shifts, day and night. It is a race against the clock – with 80 years on its neck, the shells begin to erode and poison the marine environment. Fragments of explosives such as TNT, which are considered carcinogenic, have been found near old ammunition on the bottom. The substances accumulate in marine life such as mussels and fish, according to the Environment Ministry in Berlin.
The levels are still below the threshold value for drinking water, but in a study published in February, researchers found that the concentration in some cases "approaches critical levels".
The conclusions of the ongoing project are not only important for the Baltic Sea and the North Sea. Among other things, the Black Sea faces the same challenges as a result of Russia's war against Ukraine.
This is definitely a global problem, says marine engineer Volker Hesse to AP.
In the North Sea and the Baltic Sea, there are around 1.6 million tons of undetonated ammunition from the First and Second World Wars.
This includes bombs, mines, grenades, cartridges, rockets, depth charges, and ammunition boxes. Also, a smaller proportion of chemical warfare agents – mustard gas and the nerve gases sarin and tabun – lie on the seabed.
The amount is large enough to fill a 100-mile-long freight train – a distance as long as the road between Berlin and Paris.
Most of the ammunition was sunk by the Allies after World War II, as part of the disarmament of Germany after 1945.
Some mines and undetonated bombs, however, originate from direct battles in the coastal area during the war.
Source: German Environment Ministry