Unexploded ordnance
Unexploded ordnance and unexploded bombs are explosive weapons that did not explode when they were deployed and remain at risk for detonation, sometimes many decades after they were used or discarded. When unwanted munitions are found, they are sometimes destroyed in controlled explosions, but accidental detonation of even very old explosives might also occur, sometimes with fatal consequences.
For example, UXO from World War I continues to be a hazard, with poisonous gas filled munitions still a problem. UXO does not always originate from conflict; areas such as military training bases can also hold significant numbers, even after the area has been abandoned.
Seventy-eight countries are contaminated by land mines, which kill or maim 15,000–20,000 people every year. Approximately 80% of casualties are civilian, with children being the most affected age group. An average estimate of 50% of deaths occur within hours of the blast. In recent years, mines have been used increasingly as weapons of terror; especially against local populations, such as in the Syrian civil war.
In addition to the obvious danger of explosion, buried UXO can cause environmental contamination. In some heavily used military training areas, munitions-related chemicals such as explosives and perchlorate may enter soil and groundwater, thereby contaminating the water supply, likewise with preventing agrarian uses such as farming and food distribution.
Risks and problems
Unexploded ordnance, no matter how old, may explode. It might seem that the dangers of UXO decrease over time, but this is not always the case. Corrosion and damages sustained on impact pose significant difficulties to defuse UXO safely and also make the consequences of defusion harder to predict. Mixed explosive agents might separate or migrate over time and leave contact explosives like nitroglycerine at random places in the shell. Sometimes components of the original explosives, in the presence of moisture, can form new explosive compounds with the metals in the shells like picrates that can leave a shell highly explosive, even when it is defused and the detonator destroyed or removed.Even if unexploded ordnance does not explode, environmental pollutants are released as it degrades. The toxic compounds and heavy metals can contaminate water and soil over time. Recovery, particularly of deeply-buried projectiles, is difficult and hazardous—jarring may detonate the charge. Once uncovered, explosives can often be transported safely to a site where they can be destroyed; if this is not possible, they must be detonated on site which might require evacuation of the surrounding area.
Unexploded ordnance dating as far back as the mid-19th century still poses a hazard worldwide, both in current and former combat areas and at military firing ranges. A major problem with unexploded ordnance is that over the years, the detonator and main charge deteriorate to such an extent that they frequently become more sensitive to disturbance and therefore more dangerous to handle. Construction works may disturb unsuspected unexploded bombs, which may then explode. Forest fires may be aggravated if buried ordnance explodes. Heat waves, causing the water level to drop severely, may increase the danger of immersed ordnance. There are countless examples of people tampering with unexploded ordnance that is many years old, often with fatal results. For this reason, it is universally recommended that unexploded ordnance should not be touched or handled by unqualified persons. Instead, the location should be reported to the local police so that bomb disposal or Explosive Ordnance Disposal professionals can render it safe.
Although professional EOD personnel have expert knowledge, skills and equipment, they are not immune to misfortune because of the inherent dangers: in June 2010, construction workers in Göttingen, Germany discovered an Allied bomb dating from World War II buried approximately below the ground. German EOD experts were notified and attended the scene. Whilst residents living nearby were being evacuated and the EOD personnel were preparing to disarm the bomb, it detonated, killing three of them and severely injuring six others. The dead and injured each had over 20 years of hands-on experience, and had previously rendered safe between 600 and 700 unexploded bombs. The bomb which killed and injured the EOD personnel was of a particularly dangerous type because it was fitted with a delayed-action chemical fuze which had not operated as designed, but had become highly unstable after over 65 years underground. The type of delayed-action fuze in the Göttingen bomb was commonly used: a glass vial containing acetone was smashed after the bomb was released; the acetone was intended, as it dripped downwards, to disintegrate celluloid discs holding back a spring-loaded trigger that would strike a detonator when the discs degraded sufficiently after some minutes or hours. These bombs, when striking soft earth at an angle, often end their trajectory not pointing downwards, so that the acetone did not drip onto and weaken the celluloid; but over many years the discs degraded until the trigger was released and the bomb detonated spontaneously, or when weakened by being jarred.
In November 2013, four US Marines were killed by an explosion whilst clearing unexploded ordnance from a firing range at Camp Pendleton. The exact cause is not known, although the Marines had been handing grenades they were collecting to each other, a practice permitted but discouraged. It is thought that a grenade may have exploded after being kicked or bumped, setting off hundreds of other grenades and shells.
A dramatic example of munitions and explosives of concern threat is the wreck of the SS Richard Montgomery, which was sunk in shallow water about from the town of Sheerness and from Southend. The wreckage still contains 1,400 tons of explosives. In comparison with the World War II wreck of the SS Kielce which rests at a higher depth, with a smaller load of explosives, it still exploded after a salvaging operation in 1967 and produced a tremor measuring 4.5 on the Richter scale.
Around the world
Africa
Effects of the North African campaign of World War II
During the fighting in North Africa between the Axis and Allied forces, much of North Africa was heavily mined to prevent military advances. During the conflict, in addition to the millions of mines that were placed, some of the millions of shells which were fired did not explode, and remain deadly to this day. Algeria, Egypt, Libya and Tunisia are all affected by this issue, with civilians being injured and killed every year. UXO also slows progress, with areas having to be demined before being developed.Algeria
Algeria has been contaminated with large numbers of mines and UXO throughout several wars, starting from World War II. During the Algerian war for independence, French forces laid up to 10 million mines on the Morice and Challe lines, on the eastern and western sides of the country. In 2007, France officially handed over maps to Algerian authorities showing the locations of minefields. The lack of these maps had previously severely hampered Algerian demining efforts.Further mines were laid in the Algerian civil war by both warring parties, requiring further demining efforts. However, these mining operations were not on nearly as large a scale as French operations.
By July 2016, Algeria reported that it had cleared all major minefields it had identified to clear. Thereafter, Algeria called on French authorities to provide compensation to the families of the 4000 people who are estimated to have been killed by mines, and thousands who have been left disabled from French ordnance.
Chad
Chad has been dealing with contamination issues stemming from its numerous conflicts between the 1960s and the 1980s. A significant portion of this contamination comes from the presence of anti-personnel mines, many of which are believed to have originated from Libyan sources during that period. As of 2020, estimates provided by the Mine Action Review indicated that approximately 10 square kilometers of Chadian territory remained contaminated with these dangerous antipersonnel mines. Additionally, a smaller portion of unexploded ordnance related to cluster munitions continues to affect some regions in the northern part of the country.In recent years, the ongoing jihadist insurgency led by Boko Haram has further complicated the situation. According to the Chadian government, Boko Haram and similar insurgent groups are likely responsible for laying additional mines. These groups are also known for scavenging explosives from pre-existing UXO in order to manufacture improvised explosive devices, making the clearance of these remnants of war even more critical for national security. Effective mine clearance and UXO removal are essential not only to reduce the threat of accidental detonation, but also to limit the availability of materials that insurgents might use for their attacks.