Nearly 1,600 meters below the surface of South Dakota, workers removed 800,000 tons of rock and built two giant caverns without a single serious accident — inside them, scientists will install the world’s largest underground cryogenic detector

Nearly 1,600 meters below the surface, workers excavated 800,000 tons of rock in South Dakota and built two colossal caverns without a single serious accident — all to house the world’s largest neutrino detector In the heart of an old gold mine in South Dakota, United States, workers spent years removing rock at 1,520 meters deep — almost twice the height of the Burj Khalifa, but downwards. According to the Underground Construction Association, which awarded the project the 2026 Project of the Year award, teams removed over 800,000 tons of rock from this extreme depth. The result is two gigantic caverns, each 20 meters wide, 28 meters high, and 150 meters long. Inside them, scientists will install the world’s largest underground cryogenic system to detect ghost particles called neutrinos. ARTICLE CONTINUES BELOW See also Germany surprises the world by demonstrating quantum teleportation over 30 km of commercial optical fiber using entangled photons, bringing quantum internet closer to existing infrastructure. Scientists analyze two-finger marks in rocks from China and find giant footprints up to 36 cm, preserved so unusually that a new type of trace fossil had to be created. During space missions, NASA confirms that astronauts’ skin ages faster and wounds heal worse. The disposal of trash in wrong places could face new consequences in Brazil: The Chamber of Deputies approves a fine proportional to volume and income, and the text now goes to the Senate for a final decision. Most impressively: throughout the entire excavation, workers accumulated 1,135,105 hours without any lost-time accident. Particles that pass through everything — even the entire Earth — without stopping Neutrinos are the most elusive particles in the universe. Every second, trillions of them pass through your body without you noticing. They have no electric charge, almost no mass, and rarely interact with matter. A neutrino can pass through the entire Earth from end to end without hitting anything. To detect them, scientists need absolute silence. Any cosmic radiation reaching the surface produces false signals. Therefore, the detector needs to be protected by 1,520 meters of rock — a natural shield against the noise of the cosmos. That’s why the caverns were excavated at the Sanford Underground Research Facility (SURF), a deactivated gold mine in Lead, South Dakota. Workers removed 800,000 tons of rock at 1,520 meters deep — accumulating over 1.1 million hours without a serious accident. Two caverns the size of a jumbo jet — almost 2 km deep Each excavated cavern measures 65 feet wide (20 meters), 92 feet high (28 meters), and 495 feet long (150 meters). To give you an idea, a Boeing 747 is 70 meters long — each cavern can fit more than two jumbo jets end-to-end. The scale is even more impressive when considering that everything was done almost 1.6 kilometers below the surface. The removed material had to be brought up through vertical shafts to the surface. The rock handling system was restored and expanded from the historical infrastructure of the old Homestake gold mine, which operated from 1876 to 2002. 800,000 tons of rock is equivalent to about 100,000 full concrete mixer trucks — a line that would stretch from São Paulo to Rio de Janeiro. What goes inside the caverns: the planet’s largest underground cryogenic system The caverns will house the detectors for the DUNE — Deep Underground Neutrino Experiment project, led by Fermilab, the United States’ premier particle physics laboratory. Inside each cavern, gigantic tanks will be filled with liquid argon at -186°C. When a neutrino interacts with an argon atom — a very rare event — the detector will register the resulting flash of energy. The complete system will be the world’s largest underground cryogenic detector. No previous experiment has attempted something on this scale underground. Gigantic tanks of liquid argon at -186°C will be installed inside the caverns to detect neutrinos — particles that pass through the entire Earth without stopping. 1.1 million hours without an accident: the silent record In underground construction projects at this depth, accidents are common. The heat of the rock, pressure, limited ventilation, and confined space create a hostile environment. But the LBNF/DUNE teams accumulated 1,135,105 hours worked without any lost-time accident — a record that impressed the underground engineering community. This performance was one of the factors that led the Underground Construction Association to award the project as 2026 Project of the Year. Workers faced shifts in extreme conditions: high temperatures from the rock’s geothermal heat, constant dust, and the psychological isolation of operating almost 2 kilometers from sunlight. Why hunting ghost particles matters for the real world Neutrinos may seem abstract, but understanding them could solve some of physics’ greatest mysteries. Scientists want to know why the universe is made of matter and not antimatter. If neutrinos and antineutrinos behave differently — something DUNE can measure — this would explain why we exist. Neutrinos are also produced in supernova explosions. Detecting them would give astronomers an early warning system for these cosmic events. DUNE will fire a beam of neutrinos from Fermilab, in Illinois, to the caverns in South Dakota — a distance of 1,300 kilometers through the Earth’s crust. No tunnel, no cable, nothing. The neutrinos simply pass through the rock. The Homestake gold mine, which operated from 1876 to 2002, was transformed into the Sanford Underground Research Facility to house the DUNE neutrino detector. From gold mine to future laboratory: the second act of a century-old mine The Homestake mine produced gold for 126 years. When it closed in 2002, it seemed destined for abandonment. But the same depth that made it a productive mine — 1,520 meters of solid rock above — transformed it into the perfect location for a particle physics laboratory. This second life shows how abandoned infrastructure can be repurposed for cutting-edge science. The knowledge accumulated over more than a century of mining was essential for planning the excavation. Ventilation, water pumping, and rock transport systems were restored and modernized. The experience of local miners was incorporated into the scientific project. Sometimes, the most important discoveries of the future happen in the most unlikely places — like at the bottom of an abandoned gold mine in the middle of South Dakota. The question is: what other mines in the world could have a similar second act? Sign up Connect with Access I allow you to create an account. When you first accessed our site using a Social Access button, we collected your public profile information shared by the Social Access provider, based on your privacy settings. We also obtained your email address to automatically create an account for you on our website. Once your account is created, you will be logged into that account. I disagreeI agree Notify of new follow-up comments new responses to my comments Label Name* E-mail* Save my data for the next time I comment. Save my name, email, and website in this browser's cookies for the next time I comment. ONESIGNAL ID ONESIGNAL ID I allow you to create an account. When you first accessed our site using a Social Access button, we collected your public profile information shared by the Social Access provider, based on your privacy settings. We also obtained your email address to automatically create an account for you on our website. Once your account is created, you will be logged into that account. I disagreeI agree Label Name* E-mail* Save my data for the next time I comment. Save my name, email, and website in this browser's cookies for the next time I comment. ONESIGNAL ID ONESIGNAL ID 0 Comments most recent older Most voted Built-in feedback View all comments