Maptek technology, expertise key to Chilean mine rescue

The rescue of 33 trapped miners at the San Jose copper-gold mine near Copiapó, Chile, relied on the latest mapping technology and expertise to succeed.
Entombed over 700 metres below the surface and 5 km from the mine’s entrance, the miners managed to survive 17 days before they were initially contacted.
After many attempts, a drill hole entered a work area close to the refuge where the miners had looked for shelter, and contact was made. This was the start of an amazing rescue operation which took almost two months and the combined efforts of many people.
Mining software and solutions company Maptek became involved after receiving a call on Aug. 11, 2010, from the rescue team working at the San Jose mine. It was six days into the rescue operation and the team needed help to create a 3D model of the mine and to design and visualize the deviation measurements of the drill holes.
By this time six holes had been drilled. Using the I-Site laser system, Maptek’s Estíbaliz Echevarría surveyed the area to create an accurate topographic surface.
The scanned surface information along with the 3D underground data in Vulcan model (see image) allowed the development of the first 3D video of the situation, which was used to three-dimensionally explain the relativity of the workings and the efforts being undertaken.
This data provided the rescuers with the confidence to plan and control the correct design of drill holes, and better understand the location of the 33 miners.
Drilling proceeded slowly, stopping every 100 metres to check progress. A gyroscope was lowered into the hole to capture accurate readings of the direction and orientation of the hole.
The result was that the first two drill holes intersecting the underground workings showed a distance of 1.12 metres between them. The people underground measured a distance of 1.45 metres, which means a difference of only 0.052% in 629 metres.
This data was fed back to the database established by Maptek mining engineer Alvaro Quezada. He and Maptek geologist Sandra Jara, along with Nicolás Cruz from Minera La Escondida reviewed the available data against the 3D model, projecting the drilling lines to the target to adjust the direction and orientation of the drill hole as required by the geologists and drilling personnel on site.
This information was conveyed to the drilling team who used their experience to correct the drilling rig accordingly. This process was repeated every 100 metres of the 700-metre deep hole to ensure the hole would intersect the tunnel at the targeted position.
The accuracy of the Vulcan 3D model and subsequent control of each of the three drill holes were critical factors in the success of the operation.
The first drill hole which discovered the miners was named Esperanza (Hope). The first and second drill holes were used for communications and delivery of supplies to the trapped miners. The third hole was enlarged to 71 cm to enable the Fenix rescue capsule to access the trapped miners and bring them to safety.
Maptek South American vice-president Marcelo Arancibia said Vulcan was used to design various other scenarios where holes could be drilled to potential locations. “We were using our technology while the drill rigs were drilling to depth,” he said.
The third drill hole was surveyed every 30 metres to subsequently analyze the deviation experienced by the trajectory and determine where the drilling would intercept the target. This allowed the specialists to take the necessary action during drilling.