Abstract: The system and method to inject grout into a borehole uses a leader comprising opposite fore and aft portions, a pressure-bearing member between the fore and aft portions, and a leader passage extending from a fore opening at the leader fore portion to an aft opening in the leader aft portion. A tube is attached to the leader and connected to the leader aft opening. The leader is inserted into the borehole with the fore portion first. An impelling fluid is injected in the borehole downstream of the pressure-bearing member and exteriorly of the tube, resulting in pressure being applied on the pressure-bearing member and the leader consequently advancing towards the borehole bottom end, the leader carrying the tube with it to deploy the tube in the borehole. Upstream fluid located in the borehole upstream of the pressure-bearing member is evacuated out of the borehole through the leader passage and the tube.