The Accident:
The fire at the Windscale nuclear facility in 1957 still remains as one of the most serious disasters in the history of atomic energy, and whilst now it has been overshadowed in fame by Chernobyl, Three Mile Island and Fukushima Daiichi it stands as easily the worst nuclear catastrophe in the United Kingdom and Western Europe as a whole. The first of the two graphite-moderated reactors (or 'piles') - which were being used recklessly in a last-ditch attempt to shore up the struggling British atomic weapons programme - came close to utter disaster when a fire in one of the reactor core channels was misinterpreted and the plant workers inadvertently fed the conflagration using the fans ironically used to keep the reactor cool. Despite trying to create a firebreak in the reactor by forcing out fuel rods and trying to use carbon dioxide to quell the flames, it seemed that the fire would seemingly burn out of control.
The Reactor Manager, Tom Tuohy (who lived to the ripe old-age of 90 despite his significant radiation exposure), was then faced with a do-or-die situation; with eleven tonnes of uranium ablaze inside the reactor and temperatures stretching into the extreme limits of the reactor building itself (one thermocouple registering 1300 °C above the 'white hot' reactor channels), he suggested that water be flooded into the reactor. The possibility of the molten metal oxidizing with the water, creating free hydrogen, left the risk of a colossal explosion and the complete detonation of the reactor building. When this did not happen (but the flames continued to burn), Tuohy ordered everybody out of the reactor building and turned off the huge fans that continued to push oxygen into the fire. It stopped almost immediately.
According to Wikipedia, the fire released an estimated 740 terabecquerels of iodine-131, as well as sizeable amounts of caesium-137, xenon-133 and other radionuclides. Later reworkings of affected areas have shown the amounts released may have been higher. Iodine-131 was of particular concern as whilst it has a half-life of barely more than week it can be absorbed by the body and trigger the formation of thyroid cancers - estimates of those affected are controversial and varied. Milk from the surrounding area was ditched into the Irish Sea for a month, and nowadays there are generally acknowledged to have been minimal health effects even upon those with the highest exposure rates.
The Worst-Case Scenarios
I think it can be stated comfortably that whilst the Fire was a very serious event, it generally was a near-miss. However, I am keen to find out any potential information I can about the consequences of the situation in Cumbria going disastrously wrong. I have a few circumstances in which this could have happened.
There are a wide array of political consequences from the Fire, even in our timeline, so the ramifications for the British and Western Europe geopolitical situation could - and likely will be - very significant. I would be very interested to hear your thoughts and hopefully gain some more precise statistics as to predicted radiation levels across Europe.
The fire at the Windscale nuclear facility in 1957 still remains as one of the most serious disasters in the history of atomic energy, and whilst now it has been overshadowed in fame by Chernobyl, Three Mile Island and Fukushima Daiichi it stands as easily the worst nuclear catastrophe in the United Kingdom and Western Europe as a whole. The first of the two graphite-moderated reactors (or 'piles') - which were being used recklessly in a last-ditch attempt to shore up the struggling British atomic weapons programme - came close to utter disaster when a fire in one of the reactor core channels was misinterpreted and the plant workers inadvertently fed the conflagration using the fans ironically used to keep the reactor cool. Despite trying to create a firebreak in the reactor by forcing out fuel rods and trying to use carbon dioxide to quell the flames, it seemed that the fire would seemingly burn out of control.
The Reactor Manager, Tom Tuohy (who lived to the ripe old-age of 90 despite his significant radiation exposure), was then faced with a do-or-die situation; with eleven tonnes of uranium ablaze inside the reactor and temperatures stretching into the extreme limits of the reactor building itself (one thermocouple registering 1300 °C above the 'white hot' reactor channels), he suggested that water be flooded into the reactor. The possibility of the molten metal oxidizing with the water, creating free hydrogen, left the risk of a colossal explosion and the complete detonation of the reactor building. When this did not happen (but the flames continued to burn), Tuohy ordered everybody out of the reactor building and turned off the huge fans that continued to push oxygen into the fire. It stopped almost immediately.
According to Wikipedia, the fire released an estimated 740 terabecquerels of iodine-131, as well as sizeable amounts of caesium-137, xenon-133 and other radionuclides. Later reworkings of affected areas have shown the amounts released may have been higher. Iodine-131 was of particular concern as whilst it has a half-life of barely more than week it can be absorbed by the body and trigger the formation of thyroid cancers - estimates of those affected are controversial and varied. Milk from the surrounding area was ditched into the Irish Sea for a month, and nowadays there are generally acknowledged to have been minimal health effects even upon those with the highest exposure rates.
The Worst-Case Scenarios
I think it can be stated comfortably that whilst the Fire was a very serious event, it generally was a near-miss. However, I am keen to find out any potential information I can about the consequences of the situation in Cumbria going disastrously wrong. I have a few circumstances in which this could have happened.
- What if the chimney filter - known as 'Cockcroft's Folly' - had not been installed? What would have been the levels of radiation release if the material had been able to shoot straight out of the chimney as a result of the fire? (For my own purposes, this is less useful as it requires a PoD somewhere during the construction of the plant).
- In my opinion, the greatest scope for disaster stems from a potential explosion as a result from the flooding of the reactor with water. If the molten metal in the core did react to create free hydrogen and detonated, the weakened reactor building would have simply ceased to exist. Poor Tom Tuohy, standing on the top of the reactor, would have been vaporized. If the reactor exploded in such a dramatic way, what would be the extent of the physical damage on the ground and what would have been the radiation consequences for Western Europe? In the well-known BBC documentary, Lorna Arnold (from the UKAEA) suggested the whole plant and most of Seascale would have been completely flattened. Is this game over for Cumbria at least?
- Finally, what would the consequences be if the fire simply was left to burn? For whatever reason the flames continue to be fed by the fans, and with no other option evacuation efforts are conducted. How long would the fire last and what would happen to the plant?
There are a wide array of political consequences from the Fire, even in our timeline, so the ramifications for the British and Western Europe geopolitical situation could - and likely will be - very significant. I would be very interested to hear your thoughts and hopefully gain some more precise statistics as to predicted radiation levels across Europe.