If anyone has been having problems solving this achievement, I tried to figure out what the 2 gamers were explaining, I had youtube what Mouse Chording is..
What it means is by pressing 2 buttons or holding 2 buttons in at the same time.
So this achievement is a 2 button press although it is all about the mouse which in this achievements case is Left and Right Clickers, If you have a flag with no numbers nearby you can use the 2 clickers to do this achievement, You should see your character spin around the area of dirt, The dirt will be removed.
Note* If you have 2 or more numbers shown be careful of how you approach the area.