Unfortunately, Lake Karachay isn't a great place to relax or sunbathe. In the 1990s, anyone standing on land for just one hour could be exposed to 600 roentgens of radiation, which was considered safe. Located in the Chelyabinsk region of the southern Urals, the lake has been known since the 18th century. It often dries up and sometimes even disappears from the map. Since 1951, the Mayak Production Association, one of the largest nuclear facilities in the Soviet Union, has dumped radioactive waste into Karachay, which was renamed Reservoir V-9.
In this article, we'll tell you everything you need to know about Lake Karachay, its characteristics, and why it's the most polluted lake in the world.
The most polluted lake in the world
Lake Karachay , covering approximately 1,5 square kilometers, receives radioactive discharges each year. It is believed that the lakebed contains radioactive waste in deeper layers of sediment, up to 3,4 meters deep.
In 1967, a strong wind blew through the area, scattering caesium-137 and strontium-90 (both dangerous elements exposed by the sun during the drought of the 1960s). The weather caused the elements to spread over approximately 2.700 square kilometers, putting the health of thousands of people at risk. Parts of the lake dried up during the 1960s drought, exposing dangerous elements to the sun.
Several concrete blocks and rocks were used to seal off Lake Karachay after authorities were forced to take action. The project took more than 40 years and was completed on November 26, 2015. The lake accumulated so many hazardous substances over the years that the water released more than 120 million curies, more than double the amount released into the air by the Chernobyl nuclear disaster.
Hundreds or even thousands of years from now, the lake will still be radioactive waste. It's safer to leave the lake alone rather than try to move the debris elsewhere, according to the researchers.
Lake Karachay Monitoring
Yuri Mokrov, assistant to the general manager of Mayar Productions, says that no country has the experience to maintain a stockpile of a dangerous substance like V-9. Therefore, Karachay's work will be monitored for a long time to come.
There are many traditional methods of checking water quality, including measuring gamma radiation, the amount of air near the water, and any radionuclides near the water supply. Different seasons exert different pressures on the ground, and geodetic issues are carefully considered during the design process.
Future plans for the lake include adding layers of soil and rubble to the area, and then planting grass and shrubs. Trees are not permitted because their roots could damage the concrete blocks used to create the lake. The nuclear reserve on the site cannot be affected even by a tornado, according to experts who have been monitoring the area.
palliative measures
The first steps to clean up the radiation contamination of the lake may have been taken quite late, according to some sources. Between 1978 and 1986, 10.000 concrete blocks were added to the lake to prevent the spread of contaminated sediment. These efforts ended in 2016, but the site is still considered highly contaminated. Some buildings in the area have been abandoned due to high levels of radiation in the groundwater. National Geographic reports that some of the contaminated areas are uninhabitable.
During the 1990s, spending an hour on the lake shore could generate a radiation dose of 600 roentgens, the Daily Mail reported. This is 200.000 times higher than normal radiation levels.
Other polluted rivers
Next to the Mayak power station, there is a larger lake called Lake Kyzyltash. Its water has become polluted very quickly because it is used to cool the plant's reactors. Phytoplankton in the lake have altered their rate of development and have grown faster than normal due to nuclear contamination of the water.
The Techa River originates near the city of Ozyorsk and flows through Lake Karaganda and several other lakes containing radioactive material. The Techa River merges with the Iset River, which then flows into the Tobol River in Siberia, making it one of the largest rivers in Siberia. Lakes do not exist as isolated bodies of water. They can be connected to aquifers and rivers, including the 240-kilometer-long Techa River.
In 1949, the Kyzyltash River (which flows into this lake) was the main source of water for the area because the nearby nuclear power plant was discharging contaminated water into it. Just two years later, in 1951, major flooding occurred in the region, leading to radioactive contamination of the soil near the river. Although radioactivity is believed to decrease with distance, there is no evidence that the contamination affected the entire ecosystem.
The Techa River has been contaminated with radioactivity for about 50 years. The National Cancer Institute studied 30.000 people living in the area to determine how many cancer cases were linked to the water contamination. They found that 65% of the people in the region had health problems caused by the radioactivity in the water. Specifically, there was a 21% increase in cancer cases, a 25% increase in birth defects, a 41% increase in leukemia cases, and an increase in infertility.
Accidents at Lake Karachay
In 1967, during a prolonged summer, Lake Karachay dried up so much that nuclear waste from the lakebed was blown by the winds over an area of ​​1.800 square kilometers, exposing some 400.000 people to radiation. Only 180.000 of these people were evacuated.
All accidents related to the Mayak nuclear power plant were kept secret (or at least downplayed, if not secret) by top government officials so as not to reveal their nuclear weapons programs. A curious fact is that the CIA was aware of the accidents and the Mayak nuclear power plant, but also kept it private for fear that it would put their own nuclear program at risk.
In 1987, plutonium production finally ceased when two of Mayak's five nuclear reactors shut down. Overall, more than 500.000 people were exposed to radiation after years of operation at the plant, levels approaching those caused by the Chernobyl accident.
Pollution in Lake Karachay continues to this day, and spending an hour by the lake could mean deadly radiation exposure.