The term submerged munitions refers to situations where munitions have been lost or deliberately dumped into marine, freshwater, or brackish waters, sometimes continental or underground. These are generally effects of war or military activities. Regarding the issues, there is a dual risk: sometimes of explosion and, in all cases, in the long term, of pollution caused by munitions as well as chemical contamination of food chains (in the short or medium term). More than a century after the 1918 armistice, and over seventy years after the defeat of Nazi Germany, hundreds of thousands of tons of these submerged weapons (conventional or chemical) still rest in lakes or on the seabed and remain dangerous. In the event of leaks due to corrosion, they can poison or contaminate animals (fish, shellfish, crustaceans) consumed by humans or farm animals (in the form of fishmeal and oils). Given the high costs of addressing the problem and the lack of consensus on solutions. and risk measurement, its consideration seems to have been postponed until the 2000s.
Nature and origin of submerged munitions
These can be chemical or conventional munitions. Often, they were deliberately submerged to dispose of them at lower cost, to prevent them from falling into enemy hands, or because they risked exploding or leaking due to their degraded state. Another portion, which is not the most significant, was simply accidentally lost at sea following battles, shipwrecks, scuttlings, or beachings. Some areas distributed somewhat everywhere in the world were reserved for dropping heavy munitions (bombs, torpedoes, land mines) not used during aborted missions due to weather or counter-orders. It was too dangerous for aircraft to land with their munitions, or these would have excessively increased their fuel consumption, preventing them from returning safely. These munitions were therefore dropped into the sea before returning to base, sometimes quite close to the coasts. These jettison zones are theoretically prohibited for navigation (air or sea). They mainly date from World War II, which inaugurated the method of massive aerial bombings. In the OSPAR or Channel/North Sea zone, there are at least three: near the English coast, in the Thames estuary, and another in the Strait of Dover. For example, approximately 100,000 incendiary projectiles and nearly two hundred "Cookies" were reportedly dropped by a fleet of 138 Lancaster bombers of the RAF on December 15, 1944, in the Channel, following the attack on Siegen (east of Cologne), aborted due to fog. A significant portion of these munitions did not explode and likely still rest on the bottom, at −35 m in this "Southern Jettison Area" ("jettison" in English refers to the act of throwing an object or waste overboard from a boat, submarine, plane, or helicopter; it can also refer to an aircraft dumping unconsumed fuel before a safe or emergency landing. In this case, predetermined jettison zones (called FJA "Fuel Jettison Area" by English speakers). The "Southern Jettison Area" lies under the current ascending lane of Channel maritime traffic, according to Michel Dehon. Its center is at 50°15 N and 0°15 E, with a radius of 9 km. These three RAF aerial jettison zones were not taken into account in the inventory made for OSPAR, notes Michel Dehon. Some marine and lake sites have been regularly used as target practice areas or for testing, including the special case of nuclear tests. Many unexploded ordnance have thus been lost during military tests or exercises and, in the case of misfires, not all have been recovered. Some countries (maritime or not, such as Switzerland) have used lakes and wetlands as exercise and dumping sites for obsolete munitions. In water (lake, sea, or closed wetland ...), even conventional munitions that exploded on impact can be a source of pollution by lead, mercury, or other metals.
Submerged explosives The mention "Explosives submerged" on some nautical charts refers to underwater dump sites established since the end of World War I, but many deposits seem not to have been indicated on these charts. Since then, some deposits have also been partially dispersed by currents, tsunamis, and fishing trawls. These particular "objects" seem legally assimilable to "toxic or hazardous waste" likely to release into the environment many pollutants, including eutrophying agents and some very toxic products, in dispersed quantities (DTQD), most often and initially in low doses, but chronically. The risks of explosion or sudden and significant leakage are still poorly assessed and could vary depending on depth, salinity, currents, oxygen levels, and water temperature. The consequences encompass the domains of economy, environment, public health, civil protection, military affairs, and foresight. The impacts feared by experts in demining and ecotoxicology are mainly medium and long term and concern the entire food pyramid.
Freshwater Few data are published, but ancient munitions have been massively found, for example, in Lac de Gérardmer in France or in the Jardel sinkhole (120 m vertically) from which the springs of the Loue flow, in the Doubs. In Switzerland, one lake in two has reportedly received them, including large lakes such as Lake Thun, Lake Brienz, and Lake Lucerne.
Risks and dangers
Risks of direct contact A first, direct risk is that of death or injury following the spontaneous or accidentally triggered explosion of a munition. Thus, recently in 2005, 3 fishermen were killed in the southern part of the North Sea by the explosion, on their fishing boat, of a World War II bomb caught in their nets. According to the OSPAR Commission, "The pressure exerted by the loud noise produced by spontaneous or controlled munition explosions can injure or kill certain marine mammals and fish. It has been reported that porpoises have been killed within a 4 km radius of explosions and others have suffered permanent hearing damage within a 30 km radius". A second risk is that of exposure to mustard gas, the war toxicant that has been most massively dumped at sea. According to Andrulewicz (1996), cases of capturing mustard gas in the form of viscous lumps or contamination of nets during bottom trawling have been recorded, particularly in the western part of the Polish coast, which is consistent with available data on dump sites and sea dumping routes. Some cases have been reported by the press:
Doyle (2004) quotes Danish fisherman Walther Holm Thorsen: "It was terrifying. The pain was unbearable, and my hands were blistered all over"; He was 15 years old (in 1969) when he threw back into the Baltic Sea a pierced gray canister caught in the meshes of his trawl (...), the pain came in the middle of the night, a few hours after he and another crew member had rinsed the oily substance off the fish. They had no idea it could be mustard gas. Thorsen spent three months in the hospital, and his hands are still heavily marked, despite a skin graft. "Working as a fisherman is difficult today – I often feel like my hands are frozen", he says. According to the NGO Lietuvos, in Denmark, where financial incentives reward fishermen who report munitions to the army for recovery, more than 400 such incidents have been recorded in the last two decades. According to Mitretek Systems, accidents due to contact with submerged chemical weapons have been reported in the Baltic Sea, the Adriatic Sea, the Pacific Ocean, and Japanese coastal waters. In the United States, where chemical munitions were also submerged before the 1970s, for example, from 2004 to 2012, three cases of exposure to mustard gas were reported to the CDC during dredging of seashells intended to decorate a driveway, and twice during commercial clam fishing (cases that could therefore have also affected final consumers if they had not been detected). Most often, these are fishermen who have inadvertently touched objects contaminated with mustard gas in their nets. Often, accidents recur in the same areas. In cold water, mustard gas hydrolyzes on the surface but forms a viscous mass that can persist for decades or longer. Some forms of mustard gas are particularly insoluble in water, including, according to Professor Paka, mustard gas improved for use in extreme cold ("winter mustard", intended for use in Russia, among others) with a formulation containing 37% arsenic as an additive; 20% of the mustard gas produced in Germany by the Nazis was of this type.
Toxic leaks It takes about 80 years for a munition to start leaking. The corrosion of munitions is a source of delayed toxic leaks in time and space, still poorly assessed, first because the situation is somewhat "new" in environmental history, but also because in Europe, secrecy has long surrounded marine munitions dumps; it was not until 2005 that the English public learned that the Beaufort's Dyke contained more than a million tons of munitions submerged there over more than 40 years. Concerning France, which seems to be one of the countries most affected in the world by munitions immersions, it was only in 2005 that a first official map, imprecise and without quantitative data, was published (with a five-year delay since these maps were to be published before 2000, in application of the London Convention and in accordance with the commitments of the member countries of the OSPAR Commission). The authorities responsible for these immersions seem to have long thought that there would be degradation followed by dilution of chemical toxins. However, at least in cold waters, most of the toxins from munitions have remained perfectly active after 80 years, some are neither degradable nor biodegradable (mercury, for example), and they can be quickly reconcentrated by filter-feeding organisms and the food chain. Several types of indirect risks must be taken into account, sometimes adding their effects in the form of contaminations of the ecosystem and/or marine materials (gravel pits, sand extraction) likely to be used.
Chronic leaks Recent studies (in the Baltic Sea where about sixty immersion sites were identified in 2009 but where previously undocumented munitions dumps have recently been discovered (in the Gdansk Deep), Belgium) and many indications suggest that lead, mercury, and toxic gases or liquids, as well as explosives from 1914 munitions (or later), and nitrate (propellant) or phosphorus and metals that make up the casings, shells, or linings of submerged munitions have begun to leak into the environment and could significantly affect terrestrial and aquatic ecosystems, our food, and our health. The water of the Baltic is less salty (and therefore supposed to be less corrosive), but the CHEMSEA project has shown that chemical weapons have started to leak there and pollute the sediments around the deposit sites more than theoretical models predicted, perhaps due to bottom currents strong enough to resuspend fine and polluted sediments and disperse them at a distance. Around deposit sites, biodiversity and the density of faunal communities are "poor" compared to the reference area. Cod and mussels placed in cages near the munitions show "significantly elevated molecular and cellular level responses". Isotopic analyses show that environmental contamination and that of some fish indeed come from munitions that have started to leak. These toxins could also contribute to large phenomena of dystrophication and dead zones (marine dead zones) identified by the UN. Products leaking from corroded munitions can begin or are already beginning to disperse into the waters and on the seabed. However, sands, gravels, polymetallic nodules, maerl are the subject of increasingly numerous requests for authorization to open underwater aggregate quarries. A research project (CHEMSEA, for Chemical Munitions Search & Assessment) recently (2011–2013) explored three trenches (more than 70 m deep) in the Baltic Sea where chemical munitions were submerged: Bornholm Deep, Gotland Deep and Gdansk Deep. Compared to other similar sites but without munitions, these three trenches have lost all their macrozoobenthos, and only nematodes survived among the meiofauna. The latter were therefore used as a key taxonomic group to explore the only faunal community that still tolerates this pollution: 42 genera of nematodes (belonging to 18 families) were identified there. One genus dominated: Sabatieria of the family Comesomatidae, a genus that constituted 37.6% of the global nematode community, which is not structured as in the reference sites (in terms of abundance and composition in taxons) between the dumping areas. Nematode assemblages could perhaps be used in the future as bioindicators of pollution by submerged munitions. Risks of direct or indirect contact with marine organisms; dump sites are sometimes banks that are also spawning areas or close to fishing grounds for fish, shellfish, or crustaceans. Consumers of seafood, sailors, fishermen, amateur anglers, and some boaters are at a risk that is still low but increasing, of being exposed to toxic substances, possibly gaseous. Some dump sites are very close to oyster and mussel farming areas. Toxicologists note that bacteria, fish, crustaceans, mussels, oysters, coral, sponges, and other filter-feeding organisms can – years or centuries after conflicts – reabsorb and bioaccumulate non-degradable mercury, lead, arsenic, and cadmium. Cancers and tumors are observed on fish in these areas, as well as severe damage to DNA in the Baltic Sea, but also in the Mediterranean (notably in the Adriatic Sea in congers which, due to their behavior, tend to be the first fish in contact with corroded munitions; around submerged munitions, some congers exhibit severe small or large lesions along the body, and degradation by-products of mustard gas are found in the sediment). It is known that some fish, but also some marine mammals (dolphins, belugas, whales), rub against hard objects to rid themselves of parasites or exfoliate their skin. At the end of the 20th century, notably pushed by the OSPAR Commission, some countries, as well as certain NGOs or members of the fishing industry, began to worry about the fate of submerged munition stocks in the sea or freshwater. The longer time passes, the closer these munitions are (or have already locally exceeded) a state of corrosion likely to cause significant and toxic leaks, at depths where many fish and shellfish put on the market could be affected; Cascading effects: Some immersion sites are close to industrial sites (Zeebrugge deposit in particular), major tourist sites, or even water intakes for thalassotherapy, fish farming, or shellfish farming (e.g., Cancale, Quiberon...), or near entrances to commercial or fishing ports, or nuclear power plants. Radioactive waste has been sunk on or near munitions deposits in the Hurd's Deep or the Beaufort's Dyke. Some of the pollutants released by munitions are genotoxic and therefore sources of genetic mutations that can affect generations of organisms, and the phenomenon is likely to worsen: thus, for 660 herring (Clupea harengus) captured from 2009 to 2014 in 65 study stations mainly located along the transport and immersion routes of chemical munitions in the Baltic Sea, DNA anomalies have increased in herring captured at four stations near chemical munitions immersion sites or sediments polluted by their components. And the phenomenon significantly worsened between 2010 and 2013 compared to 2009. The Bornholm sector was the most affected. The authors also note a similar problem around oil and gas platforms. Seismic risk: In Western Europe, some submerged munitions were placed where the seabed deepens, i.e., on the edge of the continental shelf, before it was learned that this is where the seismic risk is highest at sea (it is, in fact, in these regions that the epicenters of small and medium "underwater" earthquakes have been recorded, around Scotland after a seismic detection and monitoring system was gradually developed there in the 1960s and 1970s); Risk of spontaneous explosion (movements induced by earthquakes, underwater works, or passage of fishing trawls...). Noises of underwater explosions are periodically reported by fishermen at sea. Risk of dispersion of chemical toxins by water and/or air. Some deposits contain tens of thousands of tons of shells, but tonnages are cited or estimated for less than 50% of known sites. In the event of a sudden and significant release of toxins, even at a great distance, large quantities of marine organisms, including filter feeders (mussels, oysters, razor clams, cockles, and other shellfish, etc.), sea urchins or other "seafood" or carnivorous fish and marine mammals (including cetaceans) could be severely and massively affected, as well as human populations living nearby, or even farther away if a toxic cloud were to form. This is particularly a concern for the Baltic Sea, which is almost enclosed, unlike the Atlantic or Pacific. Ecotoxicological risk: This is probably the least well assessed. For a long time, mines or other unexploded ordnance were "detonated" at sea without knowing what by-products resulted from their explosion in water. It is still unknown how the toxins from munitions interact with each other and with the environment, depending on the varied conditions of pressure, temperature, salinity, current, etc. An environmental assessment and concerning maritime safety is in Germany followed by the Ministry of Agriculture, Environment, and Rural Areas of Schleswig-Holstein where, for reconstruction needs, significant quantities of munitions had already been recovered (in the 1950s and 1960s). A study in 1996 focused on products released in this region or in the Baltic Sea by the spontaneous or induced underwater explosion of explosives or submerged munitions. Two explosions of naval mines placed on the bottom were studied: the first placed at −15 m contained 100 kg of explosive (trinitrotoluene) and the other placed at −17 m contained 500 kg (TNT + RDX + aluminum). The water was sampled immediately after the explosion, in the water clouded by it up to 20 m and beyond this zone, with double sampling at three depths (at the surface, at 7.5 meters, and at 15 meters depth). In this case, the analysis (high-performance liquid chromatography) focused on the parameters TNT, (cyclotrimethylenetrinitramine or RDX), compounds of dinitrotoluene (2-amino-4,6-dinitrotoluene and 4-amino-2,6-dinitrotoluene). Tests following the DIN 32645 standard gave the following precision values:
Detection limit of TNT (2,4,6-Trinitrotoluene): 0.05 μg/l with a quantification limit of 0.16 μg/l Detection limit of Hexogen (= RDX): 0.06 μg/l with a quantification limit of 0.20 μg/l Detection limit of 2-Amino-4,6-dinitrotoluene: 0.07 μg/l with a quantification limit of 0.22 μg/l Detection limit of 4-Amino-2,6-dinitrotoluene: 0.07 μg/l with a quantification limit of 0.22 μg/l In this case (TNT explosion), none of the molecules sought were found in the water samples taken, suggesting that TNT-based explosives decompose almost completely during the explosion. When there is no explosion but slow degradation underwater, it is unknown what processes are at work. It is known that TNT (which is almost insoluble in water) can nevertheless contaminate sediments (in 2007, up to 7.1 mg of trinitrotoluene (TNT) per kg of sediment was measured in this area, although TNT levels are usually undetectable). But there are no standards or consensus on a threshold not to be exceeded in seawater or sediments. (As an indication, the German standard for soil of children's playgrounds requires not to exceed 20 mg/kg of soil). In 2007, other water samples were taken one meter below the surface and one meter above the bottom and entrusted to independent laboratories in munitions immersion areas in the regions of Kolberg, Heide, and the Kiel Fjord; they did not contain solubilized explosive molecules above the detection limit. Similarly, levels in sediments were often below the detection threshold (0.02 mg/kg). In one sample, TNT reached 7.1 mg/kg of sediment.
France In France thousands of tons of munitions were recovered after World War 1914–18. Some were dismantled, others were brought to ports from the eleven departments of the "Red Zone" or from arsenals located further south, to be dumped at sea, despite a major risk of local and global pollution of marine and coastal ecosystems. Some lakes are also affected. It also seems that wells, old mines and galleries, old wetlands, or sinkholes (e.g., Jardel sinkhole) are locally concerned. Overseas, many World War II munitions still rest, including mines, for example in the Nouméa lagoon where nearly 1,600 Mk. XIV mines (from World War II) are still present in the lagoon. Trawlers often bring up shells or other types of munitions, sometimes requiring the intervention of deminers (91 contacts were declared in 2004). They sometimes bring up rare objects; thus, 3 shells of 280 mm, 50 cm long, and weighing about 100 kg were brought up on November 30, 2007, by the Breton trawler l'Alcatraz from Lorient, 11 km from Groix island, which justified the displacement of 4 diver-deminers. The latter re-submerged these shells to destroy them underwater 2.5 kilometers east of the Gâvres point where there is a test center of the General Delegation for Armament (former Ballistics, Weapons, and Munitions Research and Study Group (GERBAM)). This type of munition, unusual, was only used by small German "pocket battleships" (Deutschland, Sheer, and Admiral Graf Spee) and the battlecruisers Scharnhorst and Gneisenau which stayed in Brest from March 22, 1941, to February 11, 1942, before returning to Germany via the Strait of Dover (Operation Cerberus). In France, the neutralization of submerged explosive devices on the maritime domain (up to the high tide mark) is the responsibility of the Navy. Thus, each year since the end of World War II, diver-deminers neutralize nearly 2,000 devices found at sea by fishermen or on beaches by walkers. The Agence des aires marines protégées and the NGO Robin des Bois alerted the Grenelle de la mer in 2009 and proposed that inventories of underwater dumps of chemical munitions and nuclear waste be completed, with an assessment of possible impacts on sedentary fauna and flora and sediments. This proposal was accepted.
United Kingdom Munitions were probably submerged as early as 1920 in Beaufort's Dyke, and about one million tons were submerged there after World War II, including munitions containing phosphorus. Under the authority of Douglas Haig, the United Kingdom (with the United States) also supervised the destruction or elimination of unexploded munitions collected in northern France at the time of reconstruction after the Armistice of 1918, while Andrew Weir (1st Baron Inverforth) was Minister of Munitions in Great Britain.
Norway According to Doyle in 2004, in areas appreciated by fishermen, Norway was still trying to locate or assess the state of 15 or even 36 wrecks of ships sunk at sea after being loaded with more than 168,000 tons of German army munitions
Problems Used, stored, or lost, munitions (including chemical shells) or their contents constitute a lasting threat.
Before the very recent appearance of munitions qualified as “green” or “non-toxic” (i.e., without lead, bismuth, antimony, arsenic, or mercury), since musket balls, practically all munitions contained toxic or very toxic components (mercury, lead, arsenic, antimony for projectiles), and chemicals or metals classified as "pollutants" or "undesirable substances" in air, water, soils, organisms, and food from certain thresholds.
Those who ordered, invented, and industrially produced (or sold) billions of toxic and polluting munitions did not plan for their end of life, and today the polluter pays principle seems impossible to apply to this type of problem. Ancient conventional munitions contain at least lead (most often enriched with arsenic and antimony to give it the desired ductility and hardness). The primers of bullets, shells, cartridges long contained mercury (in the form of fulminate), very toxic when inhaled as vapor (80% of inhaled mercury vapor passes into the blood), or transformed into methylmercury (very bioaccumulable). Since mercury fulminate is unstable, it was mixed with varnishes and gradually replaced by other products such as lead azide Pb N6, diazodinitrophenol, or nitromannite (powerful explosive with high brisance), often used as amplification charges between the detonator and the main explosive charge, in large shells and bombs. The basic component of gunpowder and propellants (charge of the casing that must propel the wounding projectile, bullet, or shell head, for example) since its discovery in China is generally nitrate, whose environmental impact and danger have been recalled by the Toulouse chemical factory explosion and the collision of a gas train with a train loaded with nitrate in Korea. Nitrates and phosphorus could be slowly purified by the environment, but they are already present in excess in the air, water, and soils of almost all of Europe, in the Channel/North Sea, and in the Baltic Sea due to intensive agriculture and other sources of pollution. Less ancient munitions also contain diphenylamine (DPA) and dibutyl phthalate (DBP). Incendiary or tracer munitions contain toxic pyrotechnic components (barium and strontium non-biodegradable, salts of hexachloroethane). Heavy metals, on the other hand, are simply not biodegradable, and their toxicity can be exacerbated in certain contexts (acid, or the ocean is acidifying) and more or less depending on their speciation (chemical form; oxides, picrates, sulfates, methylated or dimethylated form, etc.).
Responsibilities It seems accepted that in the case of the legacies of world wars, once negotiations on war damage are closed and peace agreements signed, the search for responsibility is no longer to be done, and it is then up to the States to subsidiarily manage the issue of legacies on their territories (which does not exclude subsequent cooperation agreements). Reflection has been underway on a European and global scale for a few years but has not led to a global cooperation program or common financing. An international convention commits its signatory countries to produce an inventory for the year 2000 and to have destroyed their stocks (of chemical weapons) by 2007. Few countries are up to date with their commitments.
Speed of degradation of munition casings Leaks occur after a very variable delay depending on the initial state of the munition, and depending on the conditions of the environment (the danger will then be linked to the level of toxicity, and bioavailability of the compounds of the munition, and their quantity. In cold water, nitrate cords degrade only slowly. In a stable environment (in the absence of current and passage of fishing trawl and in an undisturbed, non-bioturbated mud), the mustard gas lost by a corroded shell submerged after World War II remains "within a 3 cm radius around the shell". It is different if this shell is moved or brought up in a trawl or by the current. It is generally estimated that shells submerged from World War I must have started to leak after about 80 years, but theoretical models do not always prove reliable (perhaps due to the acidity of certain components, such as picric acid). Thus, in Hawaii, munitions have corroded faster than expected according to an American study (published in 2009). Researchers used ROVs and manned vehicles to assess in situ the integrity or state of degradation of military munitions (conventional and chemical) sunk by the Department of Defense off Hawaii (over 69 km²) south of Pearl Harbor. 1,842 non-chemical munitions were inspected on this occasion: only 5% were slightly modified, and most (66%) were heavily corroded although apparently intact; 29% were already heavily corroded and breached (contents exposed). In addition, "unusual" forms of corrosion were reported (flows that seem to have been subsequently cemented with sediment, probably due to chemical or biochemical reactions involving microbes, which could not be proven as there were no samples taken during this study); a "trapping of certain corrosion products" seems to occur in these cases. Chemical weapons are supposed to be generally stronger and made with thicker casings; they should therefore leak later. In the Baltic, where many dumps (of mustard gas in particular) were made, fishermen are already frequently burned by mustard gas brought up in their nets, and one can wonder if contaminated fish have not already been marketed. But, except for an accident or terrorist act, the potential major problems are mainly medium and long term. Because if the deliberate immersion at sea or in lakes of military waste and unexploded ordnance began massively in the years 1919–1920, with a second wave after 1945, it is around the years 2000/2005 that the shells, naval mines, torpedoes, etc. submerged at sea should – due to their corrosion – begin to leak. Those that were submerged in freshwater or in soft, oxygen-poor sediments should leak much later. Indeed, the cast iron steel that constitutes the casing of shells is on average 5 to 6 millimeters thick; it corrodes at an average rate of 0.1 to 0.5 mm/year. Moreover, picric acid, the most common explosive in 1914–1918 shells, can accelerate this corrosion and give rise to "picrates", likely to explode at the slightest shock. In addition, since shells are often stacked in thick piles, and sometimes with other types of munitions (grenades, torpedoes, mines, cartridges, etc.), the weight of those on top can crush those that have prematurely weakened below, causing sudden and significant leaks of toxins and/or eutrophying agents. The impacts of water pressure are poorly known. Some combat toxins were protected by lead packaging or in a hermetically sealed glass bottle (e.g., arsines), whose behavior at great depth is unknown.
Quantities
A first problem is that, depending on the countries and periods, the tonnages cited may concern the weight of toxins or the weight of toxins and their containers. Theoretically, since 1993, we should now clearly differentiate these two notions; in 1993, the meeting of the parties to the Chemical Weapons Convention (CWC) requested that reference be made only to the weight of chemical agents, unless expressly mentioned that it also includes the total weight of munitions or other containers (munitions and devices). Among the countries or regions that have quickly acknowledged having submerged chemical weapons are at least: Ireland, Great Britain, Scotland (Beaufort's Dyke), the Isle of Man, Australia (with notably, according to a 2003 government report, more than 21,000 tons of chemical weapons submerged off the coasts at the end of the 1940s), Russia, the United States, Japan, Canada. Belgium, in the 1980s, became aware again of the famous Zeebrugge deposit (35,000 tons), and France remained very discreet about its immersion activities but, although archives are scarce, historians had traces or indications of immersion of old munition stocks in the Mediterranean and the Bay of Biscay as well as in the Casquets Trench located between Brittany and the United Kingdom. The nautical charts of the SHOM also include some marks "explosives submerged" on the Atlantic coast and that of the Channel/North Sea. Controversies exist. For example, according to a documentary broadcast (2010/01/03) by the Swedish channel SVT, dangerous military waste (including perhaps radioactive waste) was evacuated from a former Soviet military base in Latvia and dumped at sea by Soviet ships, at night, near the island of Gotland (Sweden's economic zone), between 1989 and 1992. Vil Mirzayanov (former Russian military chemist who once worked in a secret weapons laboratory, arrested for writing articles on new chemical agents, then released) believes that immersions were a common practice at that time; to get rid of toxic materials or to hide illegal chemical weapons. Swedish politicians have called for an official investigation as a pipeline is to pass through this area. A trench near the island received a large quantity of munitions, which are starting to leak.
Millions of tons of submerged munitions are often forgotten According to French demining specialists, questioned by a commission on demining (chaired by Jacques Larché, senator), a quarter of the billion shells fired during World War I and a tenth of the shells fired during World War II did not explode during these conflicts. Moreover, it is known, from finding them, that large shells from World War I penetrated at least 15 m deep into relatively hard soils without exploding. It is feared that in marshes, peat bogs, mudflats, forest ponds, rivers, and canals, shells have penetrated much deeper. It is known that when falling on soft sediments, up to eight out of ten shells did not explode. Finally, according to some experts, about half of the munitions and incendiary materials used during the two world wars did not function on impact.
Since 1945 (the time when demining was organized, with archives in France only exploitable from 1950, and computerized from 2000), more than 660,000 tons of bombs have been cleared, as well as 13.5 million mines and 24 million shells or other explosives. France is the country most affected in Europe for the period 1914–1918 and, with Germany, for the period 1939–1945. In 56 years, 617 deminers have died in service in France where, far from slowing down, more than 80 years after the end of the 1914–1918 war, the activity of the demining service has recently been relaunched, with deminers benefiting from high-level training, but not taking into account ecotoxicological aspects or the evaluation of environmental impacts. These problems have, in France, motivated a resolution proposal (No. 331, 2000–2001), aimed at creating an inquiry commission on the presence on national territory of munition deposits from the two world wars, the storage conditions of these munitions, and their destruction (presented by MM. Jacques Machet, Philippe Arnaud, Jacques Baudot, and Rémi Herment, senators), and there is a study group on civil security and defense in the Senate. According to available data and recently provided by the respective States to the European Union and the OSPAR Commission or HELCOM, etc. Since the 1920s, more than 1 million tons of munitions (mainly conventional) have been deliberately sunk just in Beaufort's Dyke, 200 to 300 m (656 to 984 feet) deep between Scotland and Northern Ireland. A 1996 study showed no contamination of fish, but nothing guarantees the long-term harmlessness of this solution or that the fauna will not concentrate the toxins thus stored. In this region, Scottish and Irish fishermen are, by derogation, authorized to throw back into the sea munitions brought up in their nets, although the law invites them to bring them back for elimination on land when it can be done safely. Just in the Baltic, and after World War II, it would be 30,000 to 40,000 tons of chemical weapons that were submerged. At sea, dozens of major sites for immersion of waste and munitions and hundreds (thousands?) of other smaller sites exist. Many of them seem to have been forgotten or recently rediscovered by local and national elected officials. Several tens of thousands of tons (including chemical shells) are stored in each of the largest of these sites. They can sometimes be located at shallow depths (Frisian Islands) and a few cables from a coast or an industrial port (for example, for the Paardenmarkt bank where tens of thousands of tons of old munitions rest in Zeebrugge in Belgium, where a recent administrative report concluded that it was better for now not to touch this deposit), and where a pentagon is prohibited for fishing and any anchoring, but partly in an SPA (special protection area for birds) and close to fishing areas or spawning grounds or marine currents irrigating areas of essential biological productivity... Some ships during battles sank with their toxic cargo without being located. There does not seem to be a map listing these risks and dangers.
Management by country Under the auspices of the UN or other bodies, the immersion of munitions was banned in the last quarter of the 20th century by the laws of countries that ratified certain agreements and conventions. Operations for sharing information and environmental assessment are underway, including under the aegis of conventions (OSPAR, HELCOM, European directives, or resolutions of networks of communities (e.g., KIMO).
NATO On April 27, 1995, a NATO study on "Cross-border environmental problems caused by defense-related facilities or activities" was presented at the annual meeting of the CCMS (Committee on the Challenges of Modern Society) of NATO, opened for the first time to observers from PfP countries (Austria, Finland, Slovenia, and Sweden). Regarding radioactive and chemical contamination of the environment, this study notably concludes that:
Radioactive and chemical products submerged in the Barents and Kara seas, as well as the Baltic Sea, should be closely monitored (…) Submerged chemical munitions do not currently pose a threat to humans or the marine environment; however, their long-term effects should be studied. The Centre for Maritime Research and Experimentation (CMRE) has set up an underwater laboratory and test site at the SACLANT Undersea Research Centre (SACLANTCEN, SACLANT being the acronym for Supreme Allied Commander Atlantic) in La Spezia, Italy, allowing work on submerged unexploded munitions. This military research center, led by Stefano Biagini (2019), offers its users the possibility to compare various robotic systems and algorithms on site, to test, in a known environment, robotic interventions intended to protect divers in potentially dangerous or contaminated environments, among other things. The CMRE considers itself one of the world leaders in oceanography, anti-mine countermeasures, underwater autonomy, acoustic signal processing, and automatic target recognition, and it had a site in La Spezia. Experiments lasting several weeks can be conducted there, benefiting from CMRE's experience as well as services (engineering specialized, laboratory spaces, mechanical workshops, and deployment support). These services will be open to external participants and end-users, encouraging international collaboration. The CMRE claims to be impartial and "independent of NATO". It says it wants to build a "transatlantic American-European UXO Hub" in La Spezia and "establish itself as a provider of controlled experiments in the Mediterranean Sea". It says (in 2021) that it is preparing a workshop on the first feedback from the use of the CMRE UXO test bench; then a conference on the detection, classification, and identification of UXO. But the CMRE announces that it will distribute the proceedings only within NATO and the military community.
United States Through its SERDP (Strategic Environmental Research and Development Program), the Department of Defense (DoD) financially supports, in a more targeted manner, advanced technologies and research (fundamental and applied) that can improve the treatment of the problem of submerged unexploded military munitions (UXO). The objective is to reduce costs, environmental risks, and the time required to address these war waste, via three paths:
better characterize (inventory, including detection, location, and classification of munitions on the bottom or in the sediment), better repair (dismantling/’remediation‘ of submerged munitions, depollution...), better manage, scientifically, the sites concerned by these munitions. Within the Naval Research Laboratory, Dr. Shaw