Use Murray's Aboriginal Ball Form to destroy six tar drums.
After the cutscene, press to go into Ball Form and roll into the vent pipe. The pressure build-up will shoot you high in the air. Press on each impact to keep your bounces high. If you stop bouncing, the covers on each tar drum will close up and you will have to return to the vent pipe to shoot yourself up again. Keep bouncing around town until you destroy all six tar drums. After that, what the short cutscene and the job is complete.