wow you guys need to come here to Taiwan where you see the air you breath, and they have like a gazillion Scooters all pumping out polution, then ya burn fake money so dead people can pay thier way, and of course you burn the rice fields off. but you can pump air into retracts, It might not have too much dirt to work .if you can find a place big enough to fly without hitting a building.
but freon is cheap!!!!