Why not devise a self-inerting weapon?
Many of the more modern cluster munitions are equipped with munitions that can be remotely detonated or made inert. A large problem however, comes from devices that have a fuze that fails when it was supposed to function and leaves the munition unstable and unable to be remotely dealt with.
Another alternative would be a radioactive mine (say a dab of Tritium) to aid detection and clearance, but laid in sufficient numbers to be practically unclearable in battle.
If the weapon used is an area denial weapon then "battle" is not an issue and therefore anything that assists in locating them is counterintuitive.