So battle area clearance is generally what needs to be done in Laos. Laos' problem is not minefields. In fact, there are very few minefields in Laos. What Laos has is unexploded bombs (small cluster munitions that are used for anti-personnel stuff up to unexploded 750 lb bombs used to blow up stuff). As such, the detection and removal techniques are different. For mines, they have to slowly and methodically sweep over the entire area, and access to the area is very restricted. With UXO, you can generally walk over the area safely. It's not until a plow, or shovel, or whatever dislodges an unexploded bomb that it becomes very dangerous. Or, as happens in Laos, when a scrap metal scavenger purposely looks for unexploded bombs to get and sell the scrap metal to Vietnamese dealers. So anyway, battle area clearance goes like this: First, they can use a large loop detector like the one in this picture. It picks up larger pieces of metal, but will generally overlook small shrapnel pieces that would litter an area where some bombs exploded but others didn't. So the large loop detects a larger piece of metal, and they mark the area. However, the large loop cannot pinpoint, so when some metal is detected, they need to bring in a more sensitive detector.