A HIGHER-than-permitted amount of radioactive liquid material was pumped into a South African river last year, the South African Nuclear Energy Corporation has admitted. The liquid was released from the corporation’s Pelindaba facility, 30 kilometres west of the capital Pretoria, into the Crocodile River, the corporation said in a statement. The incident was the result of “an unfortunate error…” it said. The National Nuclear Regulator — which monitors South Africa’s nuclear industry — has given Necsa 24 hours to show that all measures necessary to correct the situation were implemented. The NNR has rated the incident “as a level one on the International Nuclear Event Scale.” The scale, used to classify accidents at nuclear plants around the world, has seven levels. Level one is considered an “anomaly beyond the authorised operating regime, which may be due to equipment failure, human error or procedural inadequacies.” The 1986 disaster at Chernobyl in the former Soviet Union was a level seven event.