Active and used nuclear fuel worldwide is securely contained and safely transported by rail.
Nuclear reactors at power plants utilize fissile radioactive isotopes to generate heat, which powers turbines for electricity generation. Once the nuclear fuel is depleted and cannot sustain fission reactions, it becomes waste, despite its high radioactivity. Both active and used nuclear fuel is transported between power plants and storage or reprocessing facilities in large containers known as nuclear casks. These casks must be extremely robust to prevent leaks that could threaten the environment and lead to harmful consequences.
Nuclear cask (painted white) on a freight car, ready for transport. (Photo: TrainBoard).
In the UK, nuclear casks are primarily transported by rail. For over 40 years, the UK Nuclear Fuel company has safely transported these casks across the country without any major accidents. However, pressure from anti-nuclear organizations has compelled the UK government to conduct public tests to ensure the safety of nuclear casks. These experiments aim to demonstrate that the casks are designed to withstand extreme conditions and help instill public confidence in the safety measures surrounding the transportation of nuclear materials.
On July 17, 1984, a safety test was conducted in which a 140-ton locomotive crashed into a derailed freight car containing a nuclear cask at a speed of 160 km/h. The cask contained 3 tons of steel rods to simulate nuclear fuel and was filled with water at a pressure of 689,475.7 N/m2. Despite the intense impact, the nuclear cask sustained only minor external damage and experienced very little pressure reduction. The collision occurred on a test track from Edwalton to Melton Mowbray, utilized by the British Rail Research Agency, near Old Dalby station.
The freight car, named “Flatrol”, carrying the nuclear cask was tilted on its side, appearing to have derailed. Consequently, the nuclear cask also leaned to one side while remaining inside the freight car, with the lid facing the oncoming train at the angle where the locomotive would strike its weakest point, the junction between the lid and the body of the cask. The locomotive used in the collision had been in operation since 1961 and had ceased service the year prior. During the test, the locomotive pulled three cars behind it.
The test train departed from Edwalton, located 12.9 km from the collision site, gradually increasing to the required speed. The maximum speed of the locomotive was 145 km/h, but to conduct the test, it was specially adjusted to reach 160 km/h. The locomotive was started from a distance using a switch. Additionally, magnets placed on the track could be activated to work with the train’s brakes. Upon impact, the train derailed while the nuclear cask was dragged a short distance before rolling away. The Central Electricity Generating Board noted the test was successful and believed the results would help alleviate public concerns regarding the safety of transporting radioactive fuel.
