Improbable Rescue of 'Los 33', Chilean Miners Trapped 2,300 Feet Underground

In 2010, the entire world came together to rescue 33 Chilean miners who were trapped underground for 69 days.
Marcia Wendorf

At the moment, we could all use some good news, so let's revisit the improbable rescue of "Los 33".

50 miles (80 km) northwest of the town of Copiapó, Chile, in the midst of the Atacama Desert, lies the San Jose gold and copper mine. Chile is the world's top producer of copper, and for decades prior to 2010, the country had a relatively high incidence of deaths due to mining accidents, and the San Jose mine had a particularly high number of incidents.

Location of San Jose Mine
Location of San Jose Mine. Source: NordNordWest/Wikimedia Commons

Mine owner Compañía Minera San Esteban (CMSE) (English: San Esteban Mining Company), was fined 42 times between the years 2004 and 2010 for ignoring safety regulations. To attract workers, CMSE offered higher than normal wages to Chile's already well-paid copper miners.

August 5, 2010 collapse

The various levels of the San Jose mine were accessed by a helical-shaped road that wound its way down to a depth of 2,625 feet (800 m). At 2:00 p.m. on August 5, 2010, the mine catastrophically collapsed. A group of miners working at a higher level managed to escape, however, a second group comprised of 33 men was trapped 2,300 feet (701 m) below ground.


San Jose Mine schematic
San Jose Mine schematic Source: Wikimedia Commons

Led by the duty shift supervisor, Luis Urzúa, the 33 men retreated to an underground room of around 540 square feet (50 m2) designated as a refuge. Urzúa organized teams of men to search for a way out while others took stock of how much food and water was available in the shelter.


When the roadway was found to be blocked by the collapse, the men attempted to escape via ventilation shafts, however, these were found to be missing the ladders that were required by safety codes.

The 33 men settled in to await rescue, and while the safe room was small, there were an additional 1.2 miles (2 km) of adjacent tunnels that the men could access. The main issues facing the men were a lack of food and the intense heat.

The food stocked in the shelter was only intended to last for two or three days, but the men began careful rationing, and they managed to make it last for two weeks. Their food intake was so low that each man lost on average 18 pounds (8 kg). They obtained water from an underground spring and by draining the radiators of mining equipment.

The heat of 95 °F (35 °C) and humidity at that depth meant that even after stripping off, the men were covered in sweat, and the heat caused fungal infections, and eye and respiratory problems.

To make decisions, the 33 men adopted a one-man, one-vote rule, and supervisor Luis Urzúa kept the men performing daily tasks, such as looking for an escape route. Their situation took a particular toll on the younger miners who had the rest of their lives to look forward to, and the older miners stepped in to comfort them.

The rescue begins

The day after the collapse, rescuers attempted to go down various passages but found each one blocked. Their efforts might have caused a second collapse on August 7, 2010, and attempts to reach the trapped miners through a ventilation shaft were abandoned.

Rescuers next began drilling exploratory boreholes of about 6.3 inches (16 cm) in diameter, but out of date maps caused several boreholes to miss the mine entirely. Then, on August 19th, two weeks after the collapse, one of the boreholes reached the space where the trapped miners were thought to be, but there were no signs of life.

President Piñera holds note
President Piñera holds note Source: Gobierno de Chile/Wikimedia Commons

During the two weeks since the collapse, a tent city had grown at the edge of the mine property. Called Campamento Esperanza, or Camp Hope, it housed the families of the trapped men, rescue and construction workers, and members of the media. The attempt to rescue the miners was being watched by the entire world.

Improbable Rescue of 'Los 33', Chilean Miners Trapped 2,300 Feet Underground
"Los 33" note. Source: Jose Ojeda/Wikimedia Commons

On August 22, 2010, an eighth borehole broke through into a space located at a depth of 2,257 feet (688 m). When the drill bit was brought back up to the surface, attached to it was a note which read: "Estamos bien en el refugio los 33", or in English: "All 33 of us are fine in the shelter."

Those seven words became the motto of the miners' rescue, and they were reproduced on banners and T-shirts worldwide.

Making life bearable

Authorities sent a video camera down borehole number 8, and for the first time in almost three weeks, the authorities and the families got a glimpse of their loved ones. The next day, August 23rd, the first voice contact was made with the miners.

Authorities next sent down a 5% glucose solution for the men to drink before they could begin eating solid food, along with medicine to prevent ulcers caused by lack of food. Letters from family members soon followed, and each delivery took over an hour to reach the miners.

Psychologists and doctors soon arrived at the mine site. When the Chilean Health Minister, Jaime Mañalich, described the trapped miners' situation as being similar to that experienced by astronauts onboard the International Space Station, NASA responded by sending a team comprised of two doctors, a psychologist, and an engineer.

Most of the miners were Roman Catholics, and Pope Benedict XVI sent each trapped miner a rosary, while the eldest miner, Mario Gómez, set up a chapel deep underground and led daily prayers.

The rescue plans

The Chilean government developed a rescue plan that was modeled on the Quecreek mine rescue that took place in 2002 in the U.S. state of Pennsylvania. That rescue was itself based on the 1963 Wunder von Lengede mine rescue in Germany. Both rescues made use of a rescue pod, or capsule, that winched trapped miners to the surface one at a time through an enlarged borehole.

The rescue of the Chilean miners became an international effort, involving companies and individuals from Latin America, South Africa, Australia, the U.S., and Canada. Three separate teams using three different types of equipment would bore three different holes. These included:

  • Plan A - begun on August 31st, it used an Australian-built Strata 950 raise bore machine usually used for drilling mine ventilation shafts, which would reach a target depth of 2,300 feet (702 meters) at an angle of 90 degrees
  • Plan B - begun on September 5th, it was a Schramm T130XD usually used for boring water holes, which would reach a target depth of 2,093 feet (638 meters) at an angle of 82 degrees
  • Plan C - begun on September 19th, it was a Rig 421 usually used for oil drilling, which would reach a target depth of 1,958 feet (597 meters) at an angle of 85 degrees.

Rescuers couldn't drill vertically because that would mean placing a heavy drilling rig on what was already unstable ground, so the hole drilled had to be both curved and deep. The Strata 950 was provided by the South African mining company Murray & Roberts, and it was close by, having been recently used to create a shaft for another copper mine in Chile. Weighing 28 tons, it was shipped in pieces on a large truck convoy. Plan A eventually had to be scrapped due to rock falling down the hole.

The 7-inch (18 cm) Schramm Inc. T130XD air core drill was owned by a Chilean-American joint venture, and it dug an extraordinary 130 feet (40 m) per day. A team of American drillers from the Layne Christensen Company ran the drill for 33 days straight, and additional equipment was flown in from the U.S. by UPS.

The RIG-421 was operated by Calgary, Canada Precision Drilling Corporation. At 141 feet (43 m) in height, it required 40 trucks just to bring it to the mine site. It soon ran into trouble because its size made it hard to aim at such a small target.

Fénix 2
Fénix 2. Source: Lufke/Wikimedia Commons

While the drilling was taking place, the Chilean Navy, with design input from NASA, was building three escape capsules named Fénix (English: Phoenix) 1, 2, and 3. Fénix 2, which was 21-inches (54 cm) in diameter, was finally selected. It had an oxygen supply, lighting, video and voice communications, a reinforced roof to protect against rock falls, and an escape hatch that would allow a passenger to lower himself back down should the capsule become stuck. Fénix 2 arrived at the mine site on September 25, 2010.

The rescue begins

At 8:05 on the morning of October 9, 2010, Plan B's Schramm T130XD reached the trapped miners. The rescuers next needed to inspect the borehole to determine if any parts of the shaft needed a casing to prevent rockfalls. A large concrete platform that had been built to support the winching rig needed to harden and the winching rig had to be assembled.

Rescuer Manuel González
Rescuer Manuel González. Source: Gobierno de Chile/Wikimedia Commons

At 11:00 p.m. on October 12th, with over 1 billion people around the world watching on television, rescuer Manuel González was lowered into the shaft, and he landed at the bottom at 11:36 p.m. The first four men raised were those best suited to respond to any problems they encountered and report on their journeys, and the first man out was 31-year-old Florencio Silva. He reached the surface at 12:11 a.m. on October 13, 2010. It took between 9 and 18 minutes for each man to be raised to the surface.

Supervisor Luis Urzúa
Supervisor Luis Urzúa. Source: Gobierno de Chile/Wikimedia Commons

Next raised were those in the worst physical condition, and the last raised were those with the mental toughness to endure the wait. Over the course of the next 22.5 hours, all of the remaining miners were raised. Last out was shift foreman Luis Urzúa, who upon emerging told Chilean President Sebastián Piñera, "I've delivered to you this shift of workers, as we agreed I would."

After spending 25 hours 14 minutes inside the mine, rescuer Manuel González, along with other rescuers, unfurled a banner reading, "Misión cumplida Chile" (English: "Mission accomplished Chile") before riding the last capsule up to the surface. President Piñera then sealed the rescue shaft with a metal lid.

Rescuers hold
Rescuers hold "Mission Complete" banner. Source: Wikimedia Commons

The aftermath of the rescue

After being released from the hospital, "Los 33" visited President Piñera at the "La Moneda" presidential palace in Santiago. They posed for photographs next to their Fénix rescue capsule which was on display in Santiago's Plaza de la Constitución.

Improbable Rescue of 'Los 33', Chilean Miners Trapped 2,300 Feet Underground
"Los 33" in the hospital. Source: Gobierno de Chile/Wikimedia Commons

In November 2010, "Los 33" traveled to Los Angeles to appear on CNN's "Heroes" program. The following month, 26 of the miners participated in a Manchester United soccer training session in the UK, and in February 2011, 31 of the 33 miners traveled to Israel for an eight-day tour of Christian and Jewish holy sites.

The total cost of the rescue added up to $20 million, not including costs related to Camp Hope. Private companies had donated services worth over $5 million.

Following the rescue, Chile's mining regulatory agency undertook an overhaul of its procedures, and relatives of "Los 33" filed a lawsuit against the San Esteban Mining Company. On August 4, 2013, the San Esteban Mining Company sold the San Jose mine, with some of the proceeds going to the miners, and the rest going to the Chilean government to reimburse it for the cost of the rescue.

"Los 33" collectively contracted with Los Angeles Times author Héctor Tobar who wrote the book, Deep Down Dark: The Untold Stories of 33 Men Buried in a Chilean Mine, and the Miracle That Set Them Free. In 2015 the film "The 33" was released, starring Antonio Banderas as miner Mario Sepúlveda.

During those fateful hours on October 13, 2010, the peoples of the world set aside their differences and came together as one in a celebration of life. Viva "Los 33".

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