Yup Sao Paolo is 2459ft up and has one Runway of 3700m and one of 3000m. Usually the longer one is used for departures but the shorter one should be fine for all but longest flights and hottest days.
3100m is a longish runway but you need to take into account Temperature and how far the flight is going. 1500m is enough if you only want to go for an hour or 2.