at the tip of the pump tool to rotate the pump nozzle as is shown in fig6 in this embodiment an electric motor 60 is positioned in the ct 62 near the nozzle 64 the nozzle 64 is provided with a wire brush or mill 66 operation of the motor 60 rotates the nozzle 64 and brush or mill 66 to mobilise the fill features can be added at or around the pump nozzle to mechanically agitate the fill as the nozzle is rotated fig7 11 show examples of such features in fig7 blades scallops and threads 70 are formed around the outside and inside respectively of the nozzle 72 serving to accelerate the fill as the nozzle 72 is rotated in fig8 hard buttons 74 are provided around the nozzle 72 for the same purpose in fig9 a brush 76 is connected to the pump rotor not shown and projects through the nozzle 72 into the fill as the rotor rotates the brush 76 rotates to mobilise the fill these and or other features can be used alone or in combination to improve mobilisation of the fill in another embodiment pump hydraulic power can be used to create a slow reciprocating motion of the nozzle via a low power turbine for example that can assist mobilisation of the.