Abstract: An aggregate slinger for an underground void stabilization system, the aggregate slinger comprising a vertically extending shaft and a number of dispersing members. The vertically extending shaft is inserted through a ground hole into an underground void and rotated about a vertical axis in the ground hole. The dispersing members are configured to extend radially from a lower end of the vertically extending shaft in the underground void so that the dispersing members radially spread aggregate descending into the underground void from the ground hole to form a radially enlarged support column of aggregate in the underground void.