On Level 1, go to your Work. Go straight to the Mines. There are three Jackhammer to find in the area. Go find a Jackhammer (press B to run in this area. You need to take the drink from the vending machine to be able to run in this area.). Activate it and then go to the back of it to pick up a Stone. Come back to the initial starting area to recharge your oxygen. Do this three times, and then exit out. Go back and feed to finish the job.
Watch the video for the full game walkthrough: