Or if you have half a brain just minesweep it.
S-mines are already complete cancer in the hands of a wehr player that knows how to use them. They take years to remove with pioneers -epecially if the pios are under fire-, you often lose the pios if an explosive type of weapon shoots at them while clearing, and cheeky players love to put a teller mine in the middle of the s-mine field to screw over players that wanna clear them with tanks or to increase the chance for a pioneer oneshot.
If the signs would be removed, they would turn from "cancer but somewhat balanced" to completely broken. A squad that walks into the field is dead if you dont retreat instantly after the first explosion.