10 Places Humans SEALED SHUT

Main Ideas

The video counts down ten places that were deliberately closed, sealed, or removed from use. The reasons range from protecting people from contamination to preserving fragile historical sites—and, in some cases, protecting the future from hazards that may last for millennia.

A central theme is that sealing a place does not always solve the problem. Many sites still depend on institutions, monitoring, funding, or maintenance.

10. Wittenoom, Australia — A Town Erased Because of Asbestos

• Wittenoom grew around a blue-asbestos mine. Mining ended in 1966, but asbestos waste remained near homes and other buildings.
• Asbestos fibers can become airborne and lodge in lung tissue. The contamination cannot simply be neutralized or safely removed.
• Over several decades, Western Australia demolished buildings, closed the airport, disconnected power, and revoked the town’s official status. The site was later declared contaminated.
• The narrator distinguishes Wittenoom from an ordinary abandoned town: it was actively dismantled and removed from official maps and records. Asbestos-related illnesses may continue to emerge because of their long latency.

9. Lascaux Cave, France — Closed to Preserve Its Prehistoric Paintings

• The paintings survived for thousands of years in a stable, dark environment. After the cave opened to visitors in 1948, people introduced heat, moisture, carbon dioxide, bacteria, and light.
• Heavy visitation was followed by algae growth and calcite deposits on the paintings. France closed the original cave to the public in 1963.
• Replicas were created so visitors could experience the art without entering the original. Today, access to the cave is highly restricted and carefully monitored.
• Closure did not end the threats: a black-fungus outbreak began in 2001 and was linked to the climate-control system installed to protect the cave. Lascaux illustrates how preservation efforts can themselves create risks.

8. Kola Superdeep Well, Russia — A Scientific Borehole Sealed After Drilling Stopped

• Soviet scientists began drilling in 1970 to investigate the continental crust. The well reached 12,262 meters, the deepest point humans have drilled, before work ended in 1992.
• Temperatures at that depth were far higher than expected. The heat and pressure altered the rock’s behavior and made further drilling impractical.
• The well yielded unexpected findings, including water in crystalline rock and microscopic fossils at great depth. It also challenged assumptions about the structure of the crust.
• The widely circulated recording said to capture screams from underground is a hoax; the borehole is only about 23 centimeters wide.
• The site was eventually abandoned because funding ran out, not because the well was judged dangerous.

7. Crypt of Civilization, United States — A Time Capsule Intended to Open in 8113

• Thornwell Jacobs planned the crypt after reflecting on how little evidence of everyday life survives from ancient civilizations.
• Its opening date was calculated by extending the span between an ancient date and Jacobs’s own era. It is scheduled to open on May 28, 8113.
• The sealed room contains texts and recordings, as well as ordinary objects meant to show daily life. It also includes equipment for accessing microfilm and a device intended to help future visitors learn English.
• Jacobs avoided placing valuables inside, reasoning that treasure might encourage someone to break in early.
• The crypt’s vulnerability is not just its steel door: the university must preserve the building and remember its purpose for thousands of years.

6. Giant Mine, Canada — Arsenic Waste Kept Frozen Underground

• Gold processing at Giant Mine produced arsenic trioxide, which accumulated in 14 underground chambers. The mine closed in 2004.
• Because arsenic trioxide dissolves readily in water, groundwater could carry it beyond the chambers.
• The chosen containment method uses passive thermosyphons to remove heat in winter, freezing the surrounding rock and forming a barrier intended to keep water out.
• The approach requires continuing maintenance. A major Canadian cleanup budget has been approved, while researchers continue to seek a more permanent solution.
• The video also mentions the Britannia Mine in British Columbia, where wastewater treatment must operate continuously to limit pollution. Both examples show how containment can create an ongoing obligation.

5. Qin Shi Huang’s Tomb, China — Left Unopened to Avoid Damage

• The tomb of China’s first emperor remains sealed, although the Terracotta Army was found in separate pits nearby.
• Surveys indicate a large burial chamber, and soil tests found unusually high mercury concentrations around the mound. The historian Sima Qian described rivers of mercury in the tomb, though the video cautions that his account is not eyewitness testimony.
• One reason for restraint is the damage caused when the Terracotta Army was first excavated: its painted surfaces began to deteriorate rapidly when exposed to air.
• The archaeological position described in the video is to wait until the tomb can be excavated without unacceptable loss. Unlike most sites on the list, this one remains closed by deliberate choice rather than lack of options.

4. Runit Dome, Marshall Islands — Nuclear Waste Covered by a Concrete Lid

• The United States conducted nuclear tests in the Marshall Islands from 1948 to 1958. During a later cleanup, contaminated soil and debris from multiple islands were placed in a crater on Runit Island and covered with concrete.
• The dome has no concrete base: the waste rests on porous, cracked coral, through which seawater can pass.
• Department of Energy assessments cited in the video found cracks but no immediate risk of collapse. The narrator emphasizes that the wider atoll remains contaminated and that the dome is only one part of the problem.
• Marshall Islands officials continue to seek fuller information and accountability from the United States, including for contamination beyond the dome.

3. Asse II, Germany — Radioactive Waste Being Retrieved from a Failing Mine

• About 126,000 barrels of radioactive waste were placed in the Asse II salt mine. Salt was considered suitable because it is impermeable and can gradually seal openings.
• The mine had already been extensively excavated, leaving large voids and weakened supports. The structure deformed, and groundwater began entering, undermining the assumptions behind its use as a repository.
• German authorities considered three options: fill the site with concrete, move the waste deeper into the salt, or retrieve it. They chose retrieval, despite the risks and scale of the work.
• The task involves opening chambers in a deteriorating mine, locating and inspecting corroded barrels, and bringing them to the surface over many years.
• The video’s lesson is that geology alone does not guarantee safety: prior mining and poor site assumptions can compromise a repository.

2. WIPP, United States — Salt That Gradually Seals the Waste

• The Waste Isolation Pilot Plant stores transuranic waste from U.S. defense programs in deep salt formations near Carlsbad, New Mexico.
• Salt slowly creeps inward under pressure. The plan is for each excavated chamber to close around its waste, eventually enclosing it in impermeable rock without ongoing mechanical systems.
• A 2014 radiation release followed an improper change in the packing material used for a waste barrel. The incident shut the facility for nearly three years, but the video says the salt geology itself performed as intended.
• WIPP also raises the challenge of warning people far in the future. Proposed measures include:
  • A large earthen rampart and surface monuments.
  • Thirty-two granite markers, with some buried as backups.
  • Messages in multiple languages, including Navajo, plus pictograms.
  • Information stored underground for people who might dig at the site.
• The video notes a dilemma: markers may communicate danger, but they may also attract attention. Some expert groups therefore argued that no markers could be safer.

1. Onkalo, Finland — A Repository Designed to Be Safe Without Being Remembered

• Finland’s Onkalo project is intended to store spent nuclear fuel about 430 meters underground for around 100,000 years.
• Its safety strategy uses several barriers:
  1. Place the fuel in a cast-iron insert.
  2. Enclose the insert in a copper canister, chosen for its slow corrosion in oxygen-free groundwater.
  3. Lower the canister into a vertical hole in the tunnel floor.
  4. Surround it with bentonite clay, which swells when wet and helps seal the space while accommodating rock movement.
  5. Fill and close the tunnel with clay and a concrete plug.
• Finland has tested the process using empty canisters, including the ability to retrieve a damaged one.
• In contrast to WIPP’s emphasis on warning markers, Onkalo prioritizes passive safety: the repository is meant to remain safe without maintenance, funding, supervision, or future understanding of its location.
• The video presents Onkalo as a structure deliberately designed to be forgotten.

Overall Takeaway

Most sealed sites depend on someone continuing to maintain, monitor, document, or protect them. Wittenoom needs access controls; Lascaux needs conservation; Giant Mine needs a functioning freezing system; and other sites depend on long-term institutions or cleanup programs.

Onkalo represents a different goal: safety that does not rely on future people remembering the site or continuing to care for it.

Speakers and Sources Featured

• Speaker: One unnamed narrator; the subtitles do not identify any interviewees or additional speakers.
• Sources, people, and institutions mentioned: Thornwell Jacobs; Scientific American; Sima Qian; Western Australian state data and authorities; the U.S. Department of Energy; Canada’s Giant Mine Oversight Board and Treasury Board; Germany’s Federal Office for Radiation Protection; Sandia National Laboratories; Posiva; and an unnamed filmmaker whose documentary about Onkalo is referenced.