A downhole placement tool includes an actuation (122) and a placement assembly. The actuation assembly includes a housing (226a) having a fluid pathway therethrough and an actuation piston seated in the housing to block the fluid pathway. The actuation piston is movable by fluid applied thereto to open the fluid pathway and allow the fluid to pass therethrough. The placement assembly is connected to the actuation assembly (122), and includes a housing (226b) having a pressure chamber (217b) to store the wellbore material (103) therein, a door (219), and a placement piston. The placement piston includes a piston head (264a) slidably movable in the housing, and a rod (264b) connected between the piston head (264a) and to the door (219). The piston head (264a) is movable in response to the flow of the fluid from the actuation assembly (122) into the placement assembly to advance the placement piston and open the door (219) whereby the wellbore material (103) is selectively released into the wellbore.