A method puts into operation a clearing apparatus suitable for picking up ballast and is disposed in an endless configuration during employment so as to encircle a railroad track. The clearing apparatus has a horizontal cross-duct which, prior to a start of the employment, is intended to be positioned below the railroad track and connected, on the one hand, to a rising duct and, on the other hand, to a return duct of the clearing apparatus. The method includes displacing ties of the railroad track in a longitudinal direction of the railroad track to create a tie gap; lowering the cross-duct through the tie gap between two rails of the railroad track and transferred, below the ties, into a working position extending crosswise to the longitudinal direction of the railroad track; and connecting the cross-duct to the rising duct and to the return duct.