I don't think there is a way to check if a mine gone up or not. At least I can't think of a command to check that.
# Nightrain :
I don't thinik you can check if the mine has gone off but you could do this.
Assuming the tanks are Opfor follow these steps:
1. Place a tirgger over the area you are supposed to have the tanks run over the mines (adjust it so it is big enough)
2. Set the presence to Opfor>Not Present.
3. Give an effect or a hint like this in the OnAct of the trigger: hint "Tanks destroyed";
That way if all the tanks are destroyed, you will receive a hint. The only problem with this solution is you can't account for crews that have bailed out. I'll have to think about some more.
Works but not that good, because tanks could have missed the mines and left the area unharmed. In that case the hint "tanks destroyed" is just a false assumption.
A better solution for the problem would be to check if the tanks still can move. For that do the following:
Give each of the tanks a name, here we use etank1 - etank4
Then use a trigger to check if they still can move:
Condition: !canMove etank1 AND !canMove etank2 AND !canMove etank3 AND !canMove etank4
OnActivation: hint "Tanks disabled"
However, if only one of the tanks passed the minefield the trigger gets not activated. If you want to get the hint when one of the tanks is disabled, replace AND with OR.