The 37th Street SEPTA station at the University of Pennsylvania was planning to perform caisson drilling as part of a construction project but needed to locate all of the underground utilities before starting. Master Locators provided private utility locating services to the outside edge of the SEPTA subway station tunnel walls.
How We Did It
We entered the subway tunnel with a super sonde, transmitting a signal upward adjacent to the tunnel wall. We located the signal above the surface and marked out the tunnel at ground level. After the tunnel was located, we used hydro vacuum excavation to confirm the exact location of the outside edge of the SEPTA tunnel wall.
After confirming the location of the tunnel wall, the area was cleared for caisson drilling to begin at the subway station.