Find and turn the valve in the tunnels under Spaceport

How do you complete "Find and turn the valve in the tunnels under Spaceport"?

This is step 2 of 2 in Switching the Supply, given by Celeste. It is completed on The Spaceport. The exact location is marked on the The Spaceport map.

• Switching the Supply
• The Spaceport

What are the other objectives in Switching the Supply?

Switching the Supply has 2 objectives in total: Find the tunnels under the Spaceport and Find and turn the valve in the tunnels under Spaceport.