Here is the full list of all 39 Arid achievements.
Survive 50 days in the game (any difficulty).
Read all 36 letters, notes and journals.
Repair all 84 facilities (including story related).
You escaped the atacama desert alive!
Complete the game on Tourist or harder difficulties.
Complete the game on Explorer or harder difficulties.
Complete the game on Survivalist or harder difficulties.
Complete the game on Dead Man Walking.
You discovered the secret of the waterfall.
Find the Bath Tub.
Find the curious mural.
Find the unfinished art.
Survive 10 days in the game (any difficulty).
Fix the bridge to get access to the refuge.
Found an old acquaintance.
Find where the kid has gone.
Run away from the bees! Maybe it's safer at night..
Obtained the Flare Gun.
Got access to the Saltpeter Plant.
Reach the Moon Valley.
Opened the way in the Canyon.
A sane mad man in a world of sane madness.
Discover what happened to the miners.
Encounter a sandstorm.
Find the Pool.
Find out the fate of the couple of lovers.
Read 10 letters, notes or journals.
Reach the Mining Town.
Something lurks in the darkness...
Hopefully the last one.
You unlocked access to the mines.
Repair 10 facilities.
Open your first shortcut.
Craft a herbs poultice.
Survive 1 day in the game (any difficulty)
Find a Dead Viscacha
Move on from the crashsite.
Find or craft an high quality tool.
Wake up in the Atacama desert.