Unexploded munitions

Unexploded ordnance (UXO, sometimes abbreviated as UO), unexploded bombs (UXBs), or explosive remnants of war (ERW) are explosive weapons (bombs, shells, grenades, land mines, naval mines, cluster munition, etc.) that did not explode when they were employed and still pose a risk of detonation, sometimes many decades after they were used or discarded. UXO does not always originate from wars; areas such as military training grounds can also hold significant numbers, even after the area has been abandoned. UXO from World War I continue to be a hazard, with poisonous gas filled munitions still a problem. When unwanted munitions are found, they are sometimes destroyed in controlled explosions, but accidental detonation of even very old explosives also occurs, sometimes with fatal results.

Regarding land mines, 78 countries are contaminated and they kill 15–20,000 people every year while severely maiming countless more. Approximately 80% of casualties are civilian, with children as the most affected age group. An estimated average of 50% of deaths occurs within hours of the blast. In recent years, mines have been used increasingly as weapons of terror against local civilian populations specifically.

In addition to the obvious danger of explosion, buried UXO entails can cause environmental contamination. In some heavily used military training areas, munitions-related chemicals such as explosives and perchlorate (a component of pyrotechnics and rocket fuel) can enter soil and groundwater.

Unexploded ordnance, however old, may explode. Even if it does not explode, environmental pollutants are released as it degrades. Recovery, particularly of deeply-buried projectiles, is difficult and hazardous—jarring may detonate the charge. Once recovered, explosives must either be detonated in place—sometimes requiring hundreds of homes to be evacuated—or transported safely to a site where they can be destroyed.

Unexploded ordnance from at least as far back as the American Civil War still poses a hazard worldwide, both in current and former combat areas and on military firing ranges. A major problem with unexploded ordnance is that over the years the detonator and main charge deteriorate, frequently making them more sensitive to disturbance, and therefore more dangerous to handle. Construction work may disturb unsuspected unexploded bombs, which may then explode. There are countless examples of people tampering with unexploded ordnance that is many years old, often with fatal results. Believing it to be harmless they handle the device and it explodes, causing deaths, injuries, and damage. 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 (EOD) professionals can render it safe.

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Wikipedia