The construction of linear underground installations with horizontal directional drilling (HDD) technology creates certain problems, i.e. the generation of large quantities of drilling cuttings – a problem that has not yet been fully solved. Moreover, the annular space formed between the wall of the borehole and the driven pipe is not additionally filled out. Only drilling mud and small quantities of cuttings are left there, which may later result in subsidence and collapsing of the ground over the installed pipeline. The authors present an innovative method for disposing of drilling wastes, i.e. treating the wastes and using them as mineral additives of industrial Puzzolan character to cement slurries for filling out the annular space in horizontal directional drilling.