Here is the full list of all 22 CropDuster Supreme achievements.
Complete the 'Shart' Difficulty
Gas 5000 civilians
Munch 100 burritos
Collect 100 Clocks
Complete the 'Fart' Difficulty
Munch 25 burritos
Gas 1000 civilians
Collect 25 Clocks
Clear the Wedding
Complete the 'Toot' Difficulty
Clear the Gym
Clear the Elevator
Clear the Hotel
Gas 500 civilians
Clear the Airplane
Clear the Airport
Munch 5 burritos
Clear the Gas Station
Collect 5 Clocks
Gas 100 civilians
Clear the Parking Lot
Clear Burrito Hut