Here is the full list of all 12 40 Days achievements.
Complete Easy Mode
Complete Normal Mode
Complete Hard Mode
Complete before Day 20
Complete on Day 40
Complete when Secret and City less than 10%
Complete game without kill any vigilante
Complete game without preasure any vigilante
Complete game without turn off any facilities
Complete game without remove any virus mutant effect
Full upgrade the Base
Complete game without take any action on random events