Sampling The Elephant’s Foot And Chornobyl’s Tedious Corium Clean-up

September 15, 2026 by Maya Posch 26 Comments

The site of the Chornobyl Nuclear Power Plant (ChNPP) remains a unique location, as what’s left of the No. 4 reactor is the only place in the world where you can find significant amounts of what is called corium. An amalgamation of nuclear fuel, fuel rod cladding and whatever materials like concrete that the molten mass came into contact with, Soviet scientists initially struggled to make sense of this material, leading them to even have it shot at to get samples.

In this video documentary by [That Chernobyl Guy] these struggles by scientists both in and outside the USSR to comprehend this wholly new material are detailed. Much like trinitite – created by a US nuclear weapons test – these are amalgamations of material combined under extreme conditions. In the case of the ChNPP accident, the botched turbine spin-up test and disabling of all safeties by the operators allowed the bottom core chain reaction to run unconstrained, producing the massive steam explosion that flipped the biosafety lid of the RBMK reactor, while also fully melting the core material that then melted through the concrete below the reactor.

Although this Elephant’s Foot is only a tiny fraction of the total mass of corium inside the No. 4 reactor, it got rather infamous for supposedly being highly radioactive and lethal. In reality it’s one of the least dangerous parts of the exposed corium, and repeated sampling attempts along with internal degradation due to radioactive decay and weathering before the NSC shelter was installed have led to it mostly turning into slightly radioactive, rusty-looking dust at this point.

Also covered in the video is how the corium in the destroyed reactor is likely to be retrieved for final disposal, with robots cutting into the sides of the reactor building rather than trying to navigate destroyed corridors and staircases. This way it might be possible to remove most of the material without the issues that stymied Soviet engineers in the 1980s during their sampling attempts.

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Reviewing Nuclear Accidents: Separating Fact From Fiction

July 22, 2024 by Maya Posch 94 Comments

Few types of accidents speak as much to the imagination as those involving nuclear fission. From the unimaginable horrors of the nuclear bombs on Nagasaki and Hiroshima, to the fever-pitch reporting about the accidents at Three Mile Island, Chernobyl and Fukushima, all of these have resulted in many descriptions and visualizations which are merely imaginative flights of fancy, with no connection to physical reality. Due to radiation being invisible with the naked eye and the interpretation of radiation measurements in popular media generally restricted to the harrowing noise from a Geiger counter, the reality of nuclear power accidents in said media has become diluted and often replaced with half-truths and outright lies that feed strongly into fear, uncertainty, and doubt.

Why is it that people are drawn more to nuclear accidents than a disaster like that at Bhopal? What is it that makes the one nuclear bomb on Hiroshima so much more interesting than the firebombing of Tokyo or the flattening of Dresden? Why do we fear nuclear power more than dam failures and the heavy toll of air pollution? If we honestly look at nuclear accidents, it’s clear that invariably the panic afterwards did more damage than the event itself. One might postulate that this is partially due to the sensationalist vibe created around these events, and largely due to a poorly informed public when it comes to topics like nuclear fission and radiation. A situation which is worsened by harmful government policies pertaining to things like disaster response, often inspired by scientifically discredited theories like the Linear No-Threshold (LNT) model which killed so many in the USSR and Japan.

In light of a likely restart of Unit 1 of the Three Mile Island nuclear plant in the near future, it might behoove us to wonder what we might learn from the world’s worst commercial nuclear power disasters. All from the difficult perspective of a world where ideology and hidden agendas do not play a role, as we ask ourselves whether we really should fear the atom.

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Fast Paper Tape For The Nuclear Family

December 10, 2023 by Al Williams 8 Comments

We’ve enjoyed several videos from [Chornobyl Family] about the computers that controlled the ill-fated nuclear reactor in Chornobyl (or Chernobyl, as it was spelled at the time of the accident). This time (see the video below) they are looking at a high-speed data storage device. You don’t normally think of high-speed and paper tape as going together, but this paper tape reader runs an astonishing 1,500 data units per second. Ok, so that’s not especially fast by today’s standards, but an ASR33, for example, did about 10 characters per second.

An IBM2400 tape drive, for reference, could transfer at least 10 times that amount of data in a second, and a 3400 could do even better. But this is paper tape. Magnetic tape had much higher density and used special tricks to get higher speeds mechanically using vacuum columns. It was still a pretty good trick to move 4 meters of paper tape a second through the machine.

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The Many Robots That Ventured Into The Chernobyl NPP #4 Reactor

June 22, 2023 by Maya Posch 14 Comments

Before the Chernobyl Nuclear Power Plant (ChNPP, spelled ‘Chornobyl’ in Ukrainian) disaster in 1986, there had been little need for radiation-resistant robots to venture into high-risk zones.

Yet in the aftermath of the massive steam explosion at the #4 reactor that ripped the building apart — and spread radioactive material across the USSR and Europe — such robots were badly needed to explore and provide clean-up services. The robots which were developed and deployed in a rush are the subject of a recent video by [The Chornobyl Family].

While some robots were more successful than others, with the MF-2 remote mine handling robot suffering electronic breakdowns, gradually the robots became more refined. As over the years the tasks shifted from disaster management to clean-up and management of the now entombed #4 reactor, so too did the robots. TR-4 and TR-5 were two of the later robots that were developed to take samples of material within the stricken reactor, with many more generations to follow.

The video also reveals the fate of many of these robots. Some are buried in a radioactive disposal site, others are found on the Pripyat terrain, whether set up as a tourist piece, or buried in shrubbery. What’s beyond doubt is that it are these robots that provided invaluable help and saved countless lives, thanks to the engineers behind them.

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The CCTV Cameras That Recorded The Chernobyl Disaster And Aftermath

May 29, 2023 by Maya Posch 9 Comments

The Soviet KTP-63-based remote controlled camera system, including switch and control panel. (Credit: Chernobyl Family on YouTube) — The Soviet KTP-63-based remote-controlled camera system, including switch and control panel. (Credit: Chernobyl Family on YouTube)

When we picture the Chernobyl Nuclear Power Plant disaster and its aftermath, we tend to recall just the commonly shared video recorded by television crews, but the unsung heroes were definitely the robotic cameras that served to keep an eye on not only the stricken reactor itself but also the sites holding contaminated equipment and debris. These camera systems are the subject of a recent video by the [Chernobyl Family] channel on YouTube, as they tear down, as well as plug in these pinnacles of 1980s vidicon-based Soviet engineering.

When the accident occurred at the #4 reactor at the Chernobyl Nuclear Power Plant (ChNPP) in 1986, engineers not only scrambled to find ways to deal with the immediate aftermath but also to monitor and enter radioactive areas without exposing squishy human tissues. This is where the KTP-63 and KTP-64 cameras come into play. One is reminiscent of your typical security camera, while the other is a special model that uses a mirror instead of directly exposing the lens and tube to radiation. As a result, the latter type was quite hardy. Using a central control panel, multiple cameras could be controlled.

When mounted to remotely controlled robots, these cameras were connected to an umbilical cord that gave operators eyes on the site without risking any lives, making these cameras both literally life-savers and providing a solid template for remote-controlled vehicles in future disaster zones.

Editor’s note: Historically, the site was called Чернобыль, which is romanized to Chernobyl, but as a part of Ukraine, it is now Чорнобиль or Chornobyl. Because the disaster and the power plant occurred in 1986, we’ve used the original name Chernobyl here, as does the YouTube channel.

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