After a constant increase of neutron levels, Chernobyl researchers work on a plan to prevent a new explosion.
A couple of years ago, HBO’s acclaimed series Chernobyl shed light on a devastating historical event that most of us had heard of through oral history or even through the morbid tourist trend that has put it under the spotlight in the past decades. For many of us, the magnitude of the nuclear explosion of Chernobyl seemed like ancient history and far from being a threat nowadays.
However, it seems that in the past years, the nuclear fuel of the old plant is registering increased neutron levels once again, and it doesn’t seem to be stopping any time soon. What’s happening is that the fuel-containing materials, best known as FCMs, are having fission reactions. These reactions make the neutrons strike, dividing the nuclei of uranium atoms remaining on the plant. These create energy, so if they keep increasing they can actually cause a new explosion.
“There are many uncertainties, but we can’t rule out the possibility of [an] accident,” said Maxim Saveliev, a researcher at the Institute for Safety Problems of Nuclear Power Plants (ISPNPP) in Kyiv, Ukraine.
Now, let’s not panic. According to Neil Hyatt, a renowned chemist from the University of Sheffield, the radioactive waste that is smoldering underneath the rubble looks “like the embers in a barbecue pit.” However, it’s possible that if the levels continue to rise they could end up igniting fully and result in another explosion. This explosion wouldn’t be as lethal as the original of 1986, but it’s still considered a huge hazard due to its radioactive properties.
One of the main reasons an explosion wouldn’t be that massive is because the site of the Chernobyl plant has had some maintenance since the nuclear incident. One of the measurements is a cage made of concrete and steel called the Shelter built in 1987 (one year after the tragic explosion). If an explosion were to happen again, most of the nuclear material would be contained by this Shelter.
Due to the age of the Shelter and the materials contained underneath the unit, the risk of crumbling due to the force of the explosion is still high, and if it were to happen, the threats of debris being moved and generating radioactive dust can still be extremely dangerous.
Now, what’s the problem at the moment? The neutron levels have been rising in a specific unit of the abandoned plant for the past four years. According to Maxim Saveliev, it’s likely these levels will continue to rise for more years without causing a major incident. Moreover, the nuclear materials that are smoldering at the moment will likely fizzle out on their own. However, if these neutron levels experience an uneven uprising, there will be a need to intervene immediately. The problem is that the place is not safe for humans to do something manually.
At the moment, scientists and researchers of the plant are still figuring out how to access these radioactive materials lying dangerously underneath the debris. One possibility is using robots resistant to radiation to drill exactly where the high levels are being registered. Once they go through the rubble, they can install neutron-absorbing equipment to reduce these levels. Of course, it’s easier said than done.
Two years ago, in 2019, a new protective shelter called the New Safe Confinement was built to prevent radioactive contamination on Chernobyl. But it won’t be enough if the neutron levels continue rising. Due to the emergency risk, it’s expected that the ISPNPP will present a thorough plan by September detailing the possible steps to remove or control the fuel-containing materials at the plant.
Also, scientists like Hyatt suggest that this plan should be considered or even copied by the Japanese government and scientists to apply at the site of the Fukushima nuclear disaster that happened a decade ago since it has a “similar magnitude of hazard.”