Finding the Olympus settlement at <2N 112W> isn't hard. Getting in is.
T)alk to the gate guard, and get a note.
This note must be signed by the three explorers, who are at Syrtis Major.
To find the explorers, do the following:
Cross the bridge north of Olympus.
Follow the northern bank of the northern most canal westward.
You should arrive at <10N 71E>, where the mine is.