Chernobyl Exclusion Zone surface area of Chernobyl-2 is a large underground complex that was used for anti-missile defense, space surveillance and communication, and research. Military units were stationed there. Chernobyl Exclusion Zone The Chernobyl Nuclear Power Plant Zone of Alienation (, ) is an officially designated exclusion zone around the site of the Chernobyl nuclear reactor disaster. It is also commonly known as the Chernobyl Exclusion Zone, the 30 Kilometre Zone, or simply The Zone (, ). Established by the Soviet Armed Forces soon after the 1986 disaster, it initially existed as an area of radius from the Chernobyl Nuclear Power Plant designated
Chernobyl disaster phase" and would not dissolve for 800–1000 years. Guidelines for levels of radioiodine in drinking water were temporarily raised to 3,700 Bq/L, allowing most water to be reported as safe, and a year after the accident it was announced that even the water of the Chernobyl plant's cooling pond was within acceptable norms. Despite this, two months after the disaster the Kiev water supply was abruptly switched from the Dnieper to the Desna River. Meanwhile, massive silt traps were constructed, along with an enormous 30m-deep underground barrier to prevent groundwater from the destroyed reactor entering the Pripyat River. Bio-accumulation of