The Pyhäsalmi mine, located in Northern Ostrobothnia, is the deepest base metal mine in Europe, primarily producing copper and zinc. At its deepest point, the inclined tunnel extends 1,445 meters underground, with a total length of approximately 11 kilometers. Although actual mining operations have been halted by the Canadian company First Quantum Minerals, other forms of active operations continue at the mine today.
Pyhäjärvi’s Callio offers a unique underground laboratory and testing environment, which has been utilized for diverse research, testing, and product development for decades. Activities at the mine include material testing services, energy and circular economy projects, and training. The unique humid climate of the underground environment is even suitable for cultivating edible crickets.
A traffic automation system and component placement are currently being planned for the inclined tunnel. To aid in this, a 500-meter section of the tunnel was selected for laser scanning, as the system design can be done more effectively with a precise point cloud model as the reference.
The mine has its own established coordinate system, to which the point cloud data was linked. Along the 500-meter laser-scanned section, several visually marked points were present, with X, Y, and Z coordinates previously measured with a total station. During the post-processing phase, it was straightforward to assign the pre-known coordinates to these visual markers, linking the point cloud to the established coordinate system.
The tunnel, approximately 5–15 meters wide, was scanned from the center at intervals of around 7 meters, yielding a total of 76 scan points. A 360-degree panoramic image was taken from each scan point. The laser scanning was completed in one day, with another day allocated for post-processing.
Pyhäjärvi Callio’s project manager, Nelli Hautamäki, comments on the project:
Mertala Innovations responded to our needs with a very quick turnaround, and we received the data for use extremely fast. The service was professional, and it was a pleasure to work with them. We will definitely use their services again if needed in the future.