|Fig. 1: Satellite image map of Mayak Production Association site location. (Source: Wikimedia Commons) |
The Kyshtym nuclear energy complex lies approximately 15 kilometers east of the city of Kyshtym in the eastern foothills of the south-central Ural Mountains and on the south shore of Lake Kyzyltash (see Fig. 1).  Originally known as Chelyabinsk-40, the complex was later renamed to the Mayak Production Association and served as the location for the emerging Soviet nuclear program in the years immediately following World War II.  Specifically, the facility produced plutonium for Soviet nuclear weapons from 1948 onwards. 
In April 1958, a Copenhagen newspaper reported a "catastrophic accident" involving Soviet nuclear weapons tests and linked it to the Soviet unilateral suspension of nuclear weapons tests in March 1958.  One year later in 1959, accounts of a serious accident in a "Soviet Atomic Plant" appeared in an Austrian newspaper.  Furthermore, in 1962 the incident was mentioned in "Review of Nuclear Incidents" as an "unconfirmed report of a major reactor incident."  These reports were systematically denied by Soviet Government officials.
|Fig. 2: Map of the East Urals Radioactive Trace (EURT): area contaminated by the Kyshtym disaster. (Source: Wikimedia Commons) |
After years of painstakingly researching the explosion and deducing its details from minor clues contained in published Soviet data, Zhores Medvedev, a Soviet biologist and political dissident, brought the incident to the attention of the scientific community by publishing his book "Nuclear Disaster in the Urals" in 1980.  Researchers at Oak Ridge National Laboratory in Tennessee confirmed Medvedev's findings, as they discovered that 30 villages and towns in the suspect area had vanished from current Soviet maps.  They also noted that an elaborate canal system was built to bypass 15 miles of river valley below the site.  Nine years later, the Soviet Government finally acknowledged that an explosion at a nuclear weapons factory devastated a swath of land in the Urals in 1957 and led to the evacuation of thousands of residents. 
On September 29th of 1957, the cooling system for one of the waste storage tanks failed, causing evaporation of the tank's cooling liquid and combustion of the tank's 70 to 80 tons of radioactive waste.  The chemical explosion produced an aerosol plume that attained an altitude of some 1000 meters and resulted in wide ranging dispersal of ejected radioactive material.  Approximately 90% of the 740 PBq of mixed fission products released were deposited as particulate material within 5 kilometers of the tank whilst the remaining 74 PBq of radioactive material was deposited as dry fallout over an area some 30-50 kilometers in width and some 300 kilometers in length, stretching north-north east of the Mayak facility. 
|Fig. 3: EURT territory warning sign. (Source: Wikimedia Commons)|
Some 15,000 to 20,000 square kilometers received contamination levels higher than 3.7 kBq/m2 of Sr-90.  This delineated an area of approximately 1000 square kilometers that became known as the East Urals Radioactive Trace (EURT).  A map of this region is displayed in Fig. 2. At the time of the accident, 63% of the area was used for agricultural purposes, 20% was forested and 23 rural communities existed in the area.  These populations were evacuated, amounting to some 10,700 people in total over a 22-month period after the accident.  Further utilization of the EURT territory was temporarily banned, but in 1961, reclamation of the area was initiated.  As of today, some 180 square kilometers near the site of the explosion are still officially off-limits and marked by warning signs as depicted in Fig. 3. 
© Scott Buttinger. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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