A method for sealing a wellbore, comprising the following steps: closing to fluid flow from within a wellbore tubing a plurality of longitudinally spaced apart openings in the wellbore tubing, the wellbore tubing disposed within a wellbore casing or within a wellbore liner, the plurality of longitudinally spaced apart openings in fluid communication with an annular space between the wellbore tubing and the wellbore casing or wellbore liner, the closing performed on all the plurality of openings above a lowermost one of the plurality of openings, wherein the closing to fluid flow comprises: inserting an intervention tubing into the wellbore tubing, the wellbore tubing comprising a sealing plug in its interior proximate a bottom end of the wellbore tubing; sealing a longitudinal end of the intervention tubing disposed in the wellbore tubing, the sealing comprising dropping a sealing ball or sealing dart into the intervention tubing to cause the sealing ball or sealing dart to close the longitudinal end of the intervention tubing at its lower end; actuating a seal to hydraulically close an annular space between the intervention tubing and the wellbore tubing at a position above the lowermost one of the plurality of openings and below a first one of the plurality of openings above the lowermost opening; and placing a barrier material into the intervention tubing and displacing the barrier material through the intervention tubing, through ports in the intervention tubing and placed below the seal, and then through the openings in the wellbore tubing that are exposed below the ports and into the annular space between the wellbore tubing and the wellbore casing or wellbore liner; displacing the barrier material through the lowermost opening into the annular space to a level below the first one of the plurality of openings above the lowermost opening; exposing to fluid flow the first opening above the lowermost opening by the intervention tubing being pulled upwardly, the exposing comprising maintaining closure of all of the plurality of openings above the first exposed opening; and placing a barrier material in the wellbore tubing and displacing the barrier material through the first exposed opening into the annular space. inserting an intervention tubing into the wellbore tubing, the wellbore tubing comprising a sealing plug in its interior proximate a bottom end of the wellbore tubing; sealing a longitudinal end of the intervention tubing disposed in the wellbore tubing, the sealing comprising dropping a sealing ball or sealing dart into the intervention tubing to cause the sealing ball or sealing dart to close the longitudinal end of the intervention tubing at its lower end; actuating a seal to hydraulically close an annular space between the intervention tubing and the wellbore tubing at a position above the lowermost one of the plurality of openings and below a first one of the plurality of openings above the lowermost opening; and placing a barrier material into the intervention tubing and displacing the barrier material through the intervention tubing, through ports in the intervention tubing and placed below the seal, and then through the openings in the wellbore tubing that are exposed below the ports and into the annular space between the wellbore tubing and the wellbore casing or wellbore liner; displacing the barrier material through the lowermost opening into the annular space to a level below the first one of the plurality of openings above the lowermost opening; exposing to fluid flow the first opening above the lowermost opening by the intervention tubing being pulled upwardly, the exposing comprising maintaining closure of all of the plurality of openings above the first exposed opening; and placing a barrier material in the wellbore tubing and displacing the barrier material through the first exposed opening into the annular space.