The Eufaula Tunnel

"Now that the Portia Bridge is complete, we're moving on to phase two of the project. Mint has planned for us to drill a tunnel through the Eufaula Range to connect with the road on the other side. This will take a while. We'll be in need of some materials for the ceiling and walls for the tunnel, I'll be posting these at the Commerce Guild starting tomorrow."

- Letter from Albert

Once the mission The Portia Bridge is complete, Albert will send you a letter in the mail requesting your help with the development of the Eufaula Tunnel. He needs you to complete several commissions. Accept as many as you can and get to work. Note: These commissions unlock new diagrams for new assembled items and provide respectable rewards upon completion:

When all of the commissions are finished, head to the tunnel in the Eufaula Desert. There have been mini-earthquakes in the tunnel when they drill, and Mint wants a second opinion on what's causing it. As you start to enter the tunnel, a small quake will cause it to collapse, trapping Arlo, Sam, and Mint inside. When you're ready, follow Remington to start the rescue mission.