On April 26, 1986, while a systems test was being carried out at reactor 4 of Chernobyl Nuclear Power Plant near Pripyat – now a ghost town in Northern Ukraine, a power surge happened and it ended in a major blast that caused hundreds of deaths due to the lethal exposure to radiation. This accident is considered one of the two worst nuclear incidents in the history, reaching level 7, the other one being Fukushima accident in 2011 – the same year Chernobyl officially became a tourist attraction.

Since the nuclear blast happened, the world remembers Chernobyl as one of the most dangerous and scariest places on earth. The plant and towns surrounding it have been abandoned. But, did you know there is actually another place in Russia that is more dangerous than Chernobyl? It is Lake Karachay, located in central Russia to the south of Ural Mountains.

When you think of a lake, you might have beautiful images about it; sparkling water surface hit by the morning sun, swimming swans, or the romantic mirrored sunset. But, in Lake Karachay, spending an hour on its bank could mean death. Not exactly like the lakes you have visited, right? So, what exactly makes Karachay so dangerous? It is the most polluted lake on earth. The Soviet Union started to use Karachay as a dumping site in 1951 for radioactive waste from the Mayak Production Association, one of the biggest nuclear facilities in Russia. Although today the lake is completely infilled, almost the whole bed of the lake is composed of high level of radioactive waste. Considering the size of Karachay that is not so big, only about 45 hectares, the level of exabecquerels reaches 4.44 with 3.6 EBq of caesium-137. That number is way higher than Chernobyl that released only 0.085 of EBq caesium-137.

What is caesium-137? It is a radioactive isotope used in nuclear reactors and nuclear weapons. It is water-soluble and once it enters the blood can easily be distributed to the whole body and can cause death. You can imagine how much of the compound you can possibly inhale while staying around the lake and endanger your health.

The Mayak plant was built quietly between 1946 and 1948 by the Soviet Union to create plutonium for the Soviet atomic bomb project to match America’s nuclear superiority. To cool down the radioactive waste stored in the facility’s underground vat, Mayak needed a lake to cycle the waste. The initial plan was to let the water lower the waste’s temperature before it can be transferred back into the vat. But the plan failed since the waste proved to be lethal and impossible to be brought up after getting dumped into the lake. And so, that was how Karachay – which means Black Water – became very, very polluted and toxic.

In 1957, a disaster happened in Mayak. The underground vat exploded because of an error in the cooling system and contaminated the whole Mayak area. That was the year when Karachay quit being used as a dumping site. In 1960, the lake started to dry out and when the drought swept the whole area in 1968, the dried lake released radioactive dust that exposed half a million people in the surrounding area to radiation. This raised people’s protest which made the authorities agreed to cover the bed of the lake with ten thousand concrete blocks to prevent the toxic elements from getting flown by the wind.

Maybe you wonder how it is doing today. Is it safe to be visited? Has it turned into a tourist attraction? The answer is: no. Not yet, or perhaps never will be. Although the experts say it is safe after being sealed with concrete, but a continuous monitoring still has to be done. This monitoring will take years considering the amoun of waste “sleeping” under the floor of the lake. The experts will make sure no radiation leak happens, no movement of ground, and no more contamination to any of the nearby water sources that the people use for their daily needs. In the future, layers of rubble and solid will be added above the concrete so bushes and grass can be grown there to cover the whole area of Karachay. Planting of trees will be prohibited because the growth of the root can ruin the concrete layer and may cause a leak. You can see how serious the pollution of Karachay is from all the treatment plans and how careful the experts handle the site.

Can you find Lake Karachay on the map? Definitely! Well, Mayak was a secret until it started to appear on the map in the 1990’s. But Karachay can clearly be located if you try and look it up. What happened to the people who lived around the lake and Mayak plant when the radioactive waste dumping started to take place? They clearly got poisoned. Besides Karachay, the waste was also thrown into Techa River that became the water source to majority of the people there. After consuming the water for some time before the warning turned up, sickness started to spread. Cancer increased by 21%, birth defect by 25%, and leukemia by 41% – all because of the nuclear waste. Some people tried to move upward to the Ural Mountains, but a lot of them didn’t survive for too long because the pollutant already made way into their system. Under tight observation, though, the water of Techa River is now safe to be consumed.

Learning from what happened in Lake Karachay, Russia, that is proven to be more dangerous than Chernobyl, the issue of nuclear as source of energy is still gaining pros and cons until today. Environmentalists believe that there are a lot more eco-friendly and safe renewable power source to use other than nuclear. But the industrialists are holding on to the fact that incidents like Chernobyl, Fukushima, and Mayak very rarely happen and, with today technology and regulations, the nuclear plants can be securely handled and monitored so they can benefit the world without endangering the population.