Six-legged robotic bugs, armed with metal detectors that scan the ground marking possible land mine locations. Radar machines that can go over an area and find out what lurks beneath the ground. Infrared imaging devices that use temperature variations to find mines. Hot-air balloons that detect inaccessible minefields from the air.
All of these have been touted in recent years as the ultimate breakthrough in land mine detection. The only problem is, they don’t work.
None of the various high-tech solutions has changed the basic routine of finding land mines: A worker, crawling along the ground, prodding the soil with a long rod.
The process is laborious and time-consuming, but it’s the only way, say land mine experts.
“With the technology we have, we can put a man on the moon, we can map the human genome—but a person with a detector is still the most reliable way [to clear land mines],” said Jay Steed, regional general manager for the private US-based company UXB International.
The basic reason, Steed said, is simple: “Technology cannot identify what’s in the ground without someone digging it up and looking at it.”
Cambodia has one of the highest levels of land mine contamination in the world—some estimates put the number of mines here as high as six million.
In recent years, land mines have been brought into the international spotlight. In 1997, US citizen Jody Williams and her International Campaign to Ban Land mines won the Nobel Peace Prize, and 122 countries have now ratified the Ottawa Convention, which prohibits manufacture or use of the deadly weapons.
Once thought to be a necessary component of military strategy—they were laid chiefly to protect anti-tank mines from removal—anti-personnel mines are now seen as a lethal scourge.
They can be purchased cheaply and can even be handmade fairly easily. They target human beings with the goal of maiming or killing. And long after a conflict, they remain in the soil to threaten the civilian population.
The land mines liberally laid to defend territory in decades of conflict in Cambodia are predominantly in the old Khmer Rouge strongholds of the northwest. Now that the various wars are over, they inhibit efforts to resettle and develop the country.
Removing them is an agonizingly slow process. Standard manual demining involves a worker crawling along on his stomach with a metal detector, which will pick up anything metallic, not just mines. If the detector senses something, the deminer uses a long rod to cautiously prod into the ground at an angle, to avoid setting off a mine.
Most of the time, it’s an innocuous scrap of metal, a piece of shrapnel or an empty cartridge. Because of all the false alarms, because any trees or brush in the way must be cut before the ground can be scanned, and because deminers must proceed so cautiously, it can take hours to clear just one square meter manually.
“In heavy vegetation or heavy scrap metal-contaminated areas, you may only clear three to five square meters per man per day,” Steed said.
So land mine activists and scientists the world over have been racking their brains for ways to use technology to speed the process. But so far no magical device has appeared to clear vast swaths of mined land in one fell swoop.
The basic problem, experts say, is that there are simply too many variables. “There are too many different kinds of land mines, environmental factors, physical factors,” said Massoud Hedeshi, program manager for mine action for the UN Development Program in Cambodia.
“Some territories lend themselves to [sophisticated] technology,” Hedeshi explained. “You can have a high-tech digital unmanned scanner—people have even talked about doing it from the satellite level—but you need the right terrain. You can’t do it with trees in the way.”
In heavily mined Afghanistan, where much of the country is dry and rocky, ground scanning might work. But in Cambodia, trees and heavy brush are usually in the way.
In addition, human judgment just can’t be imitated by even the smartest computer. “Even after you scan with a machine, you still need someone to identify the object, see if it contains explosives and dig it up,” Steed said.
If a piece of equipment could make this judgment, demining would be vastly easier. “The big breakthrough would be a true mine detector,” said Hemi Morete, a UNDP mine action specialist who first did demining work in Cambodia a decade ago as an Untac peacekeeper with the New Zealand Army.
Well-funded researchers in the US, Canada and Europe are all trying to find this Holy Grail. But the problems associated with it are so complex that a “true mine detector” looks to be a long way off.
“I don’t think there’s going to be a silver bullet, a magic machine,” Morete said. “It’ll be a lot of little steps.”
Little steps certainly have been made in land mine detection, but they are largely crude and low-tech. Perhaps the most significant is the use of explosive-sniffing dogs. The dogs’ noses are so sensitive that they can detect just a few grams of TNT.
Dogs imported from Sweden have been working in Cambodia since 1999. (Their Cambodian handlers learn the Swedish language to give them commands.) They walk slowly in a straight line, doubling back and forth. If they smell something, they stop and sit down.
The dogs are especially valuable for eliminating the large areas of a suspected minefield that are not actually contaminated. Because they detect the presence of explosives, they can find plastic mines that a metal detector can’t. They also detect unexploded ordnance.
In some areas, especially roads, armored vehicles can ride across a minefield, setting off whatever mines they run over. Flail machines, which use spinning chains to beat the ground and set off mines, can also work in vegetation-free areas. These vehicles may be manned or remote-controlled.
But in Cambodia, where most mines are in vegetated areas, the biggest boon has been