In exploitation of deep open-pit one of the main problems is increasing stability pit wall during making it in final position. As is generally known, to provide over contour massive in safety is used one of widespread blasting method – the pre-split blasting. In given work is proposed to use gel explosive Gelpor GP-2У to make a quality reflection crack for Kostomuksha ore open pit geological structure. Were made a calculation of basic parameters in pre-blasting method with using gel explosive Gelpor GP-2У and given estimation of calculation result with experimental data, using on Kostomuksha ore open pi in pre-split blasting.
