Iyo NPD yakatevedzana pombi jacking muchina inonyanya kukodzera mamiriro eiyo geological ane yakakwira pasi pemvura kudzvanywa uye yakakwirira ivhu permeability coefficient. Iyo slag yakacherwa inoputirwa kunze kwemugero nenzira yematope kuburikidza nepombi yematope, saka ine maitiro ekushanda kwepamusoro uye nzvimbo yekushanda yakachena.