Here is the full list of all 32 The Sapper achievements.
Complete easy mission
Find a mine with the first click
Run out of time
Go to the paid mission
Win a 13x13 quick game
Win a 20x20 quick game
Win a 25x25 quick game
Complete normal mission
Complete hard mission
Fail the paid mission
Use helper to open some fields
Collect $50
Collect $1000
Collect $10000