The accident at Fukushima nuclear power plant occurred on 20 1 1. Accidents caused by earthquakes and tsunamis caused damage to nuclear reactors, resulting in the leakage of a large number of radioactive materials. Due to the damage of nuclear power plant infrastructure, groundwater and rainfall water infiltrated into the damaged nuclear reactor and contacted with radioactive substances, forming wastewater containing radioactive substances.
Fukushima nuclear power plant continued its cooling work, using water to cool the damaged nuclear reactor. After the cooling water comes into contact with radioactive substances in nuclear reactors, it becomes waste water containing radioactive substances. In order to reduce the volume of nuclear waste water and the concentration of radioactive substances, the Japanese government treats nuclear waste water through different treatment methods, such as ion exchange, reverse osmosis and evaporation concentration. However, even after treatment, by-product wastewater containing radioactive substances will still be produced.
Influence of nuclear sewage
Under the action of equatorial current, pollutants spread rapidly along the coast of America to the South Pacific, and also transferred to the Indian Ocean through the northern waters of Australia. Although the nuclear waste water is discharged near Fukushima, with the passage of time, the area with high pollutant concentration will extend eastward along the 35 N line and spread from the sea near East Asia to the sea near North America.
On the 2400th day, the concentration of pollutants in the southeast coast of China was low, and the concentration of pollutants in the west coast of North America was high. In the early stage of nuclear wastewater discharge, the main concern is its impact on the Asian coast. However, in the later period, the concentration of pollutants in the coastal waters of North America will continue to be higher than that in most coastal waters of East Asia, so it is necessary to pay special attention to the affected situation in the coastal waters of North America.