Demining
Demining or mine clearance is the process of removing land mines from an area. In military operations, the object is to rapidly clear a path through a minefield, and this is often done with devices such as mine plows and blast waves. By contrast, the goal of humanitarian demining is to remove all of the landmines to a given depth and make the land safe for human use. Specially trained dogs are also used to narrow down the search and verify that an area is cleared. Mechanical devices such as flails and excavators are sometimes used to clear mines.
This article is about the removal of land mines. For the removal of naval mines, see Minesweeping.
A great variety of methods for detecting landmines have been studied. These include electromagnetic methods, one of which (ground penetrating radar) has been employed in tandem with metal detectors. Acoustic methods can sense the cavity created by mine casings. Sensors have been developed to detect vapor leaking from landmines. Animals such as rats and mongooses can safely move over a minefield and detect mines, and animals can also be used to screen air samples over potential minefields. Bees, plants, and bacteria are also potentially useful. Explosives in landmines can also be detected directly using nuclear quadrupole resonance and neutron probes.
Detection and removal of landmines is a dangerous activity, and personal protective equipment does not protect against all types of landmine. Once found, mines are generally defused or blown up with more explosives, but it is possible to destroy them with certain chemicals or extreme heat without making them explode.
Contamination and clearance[edit]
As of 2017, antipersonnel mines are known to contaminate 61 states and suspected in another 10. The most heavily contaminated (with more than 100 square kilometres of minefield each) are Afghanistan, Angola, Azerbaijan, Bosnia and Herzegovina, Cambodia, Chad, Iraq, Thailand, Turkey, and Ukraine.[25] Parties to the Mine Ban Treaty are required to clear all mines within 10 years of joining the treaty, and as of 2017, 28 countries had succeeded. However, several countries were not on track to meet their deadline or had requested extensions.[26]
A 2003 RAND Corporation report estimated that there are 45–50 million mines and 100,000 are cleared each year, so at present rates it would take about 500 years to clear them all. Another 1.9 million (19 more years of clearance) are added each year.[7] However, there is a large uncertainty in the total number and the area affected. Records by armed forces are often incomplete or nonexistent, and many mines were dropped by airplane. Various natural events such as floods can move mines around and new mines continue to be laid.[27] When minefields are cleared, the actual number of mines tends to be far smaller than the initial estimate; for example, early estimates for Mozambique were several million, but after most of the clearing had been done only 140,000 mines had been found. Thus, it may be more accurate to say that there are millions of landmines, not tens of millions.[28]
Before minefields can be cleared, they need to be located. This begins with non-technical survey, gathering records of mine placement and accidents from mines, interviewing former combatants and locals, noting locations of warning signs and unused agricultural land, and going to look at possible sites. This is supplemented by technical survey, where potentially hazardous areas are physically explored to improve knowledge of their boundaries.[29] A good survey can greatly reduce the time required to clear an area; in one study of 15 countries, less than 3 percent of the area cleared actually contained mines.[30]
Economics[edit]
By one United Nations estimate, the cost to produce a landmine is between $3 and $75 while the cost of removing it is between $300 and $1000.[31] However, such estimates may be misleading. The cost of clearance can vary considerably since it depends on the terrain, the ground cover (dense foliage makes it more difficult) and the method; and some areas that are checked for mines turn out to have none.[32]
Although the Mine Ban Treaty gives each state the primary responsibility to clear its own mines, other states that can help are required to do so.[33]
In 2016, 31 donors (led by the United States with $152.1 million and the European Union with $73.8 million) contributed a total of $479.5 million to mine action, of which $343.2 million went to clearance and risk education. The top 5 recipient states (Iraq, Afghanistan, Croatia, Cambodia and Laos) received 54% of this support.[34]
![Hydrema mine clearing vehicles use flails.[61]](http://upload.wikimedia.org/wikipedia/commons/thumb/4/48/Hydrema_mine_cleaning_vehicle.jpg/368px-Hydrema_mine_cleaning_vehicle.jpg)
Removal methods[edit]
Humanitarian[edit]
Once a mine is found, the most common methods of removing it are to manually defuse it (a slow and dangerous process) or blow it up with more explosives (dangerous and costly).[135] Research programs have explored alternatives that destroy the mine without exploding it, using chemicals or heat.[136]
The most common explosive material, TNT, is very stable, not burnable with a match and highly resistant to acids or common oxidizing agents. However, some chemicals use an autocatalytic reaction to destroy it. Diethylenetriamine (DETA) and TNT spontaneously ignite when they come in contact with each other. One delivery system involves a bottle of DETA placed over a mine; a bullet shot through both brings them in contact and the TNT is consumed within minutes. Other chemicals that can be used for this purpose include pyridine, diethylamine and pyrole. They do not have the same effect on explosives such as RDX and PETN.[136]
Thermal destruction methods generate enough heat to burn TNT. One uses leftover rocket propellant from the NASA Space Shuttle missions.[137] Thiokol, the company that built the engines for the shuttles, developed a flare with the propellant. Placed next to a mine and activated remotely, it reaches temperatures exceeding 1,927 °C (3,501 °F), burning a hole through the landmine casing and consuming the explosive.[137] These flares have been used by the US Navy in Kosovo and Jordan.[138] Another device uses a solid state reaction to create a liquid that penetrates the case and starts the explosive burning.[136]