Japan stores 50,000 tons of ultra-pure water 1 km deep underground, what is the purpose for more than 20 years?

Although more than 70% of the earth’s surface is covered by water, but the actual water for human use is very little, more importantly, in various resources, water is a resource that can not be replaced, so water scarcity has become one of the world’s attention important issues.

Water scarcity | SIWI

Since the water for human use are so little, why Japan still has to store 50,000 tons of ultra-pure water in the underground 1000 meters, a deposit is still stored for more than 20 years, this is why? Japan has some ulterior motive?

Extremely high purity of water – ultra-pure water.
In our daily lives, we often come into contact with water, basically have impurities, such as mineral water, spring water, etc., which has minerals, and tap water and water rust, chloroform after the residual impurities, and we believe that the more pure distilled water, in fact, there is air dissolved in it, there are impurities, so in our perception of water can conduct electricity.

But in fact, pure water should be insulated body, according to the conductivity of water can come to determine whether the water is pure, because at room temperature, the more insulated water is pure, according to this judgment standard, we require ultra-pure water resistance at room temperature to be greater than 18 megohm-cm.

Compared with other water, ultra-pure water is very clean, can be understood as no impurities, even the various molecules in the air are not, only water molecules, so ultra-pure water need to go through distillation, deionization, reverse osmosis technology and other technical depth treatment, the general process is very difficult to achieve, is mainly used in the industrial field and the field of medicine and optical field.

Japan will be 50,000 tons of ultrapure water stored in the ground, some people first thought of the storage of water, this idea is certainly not right, if only for drinking, direct storage of water on the line, why do we have to go to great lengths to create ultrapure water and then stored?

In addition, the purity of ultra-pure water is very high, does not contain substances beneficial to the human body, but also does not contain substances harmful to the human body, but into the human body, it may cause a decrease in extracellular fluid permeation pressure, the human body is harmful, not conducive to drinking.

Japan has stored 50,000 tons of ultrapure water at a depth of 1,000 meters  underground. What is its purpose? | Luju Bar

Ultra-pure water is for the detection of neutrinos.
Neutrino is one of the most fundamental particles in nature, the speed of this particle is close to the speed of light, and any material interaction is extremely weak, it is considered almost no effect, so the detection of neutrinos is a very difficult thing.

But then scientists gradually found that neutrinos and water will rub a different spark, when neutrinos pass through ultra-pure water will emit a shorter wavelength of electromagnetic radiation and be observed by existing technology, so ultra-pure water has become a sign of detecting neutrinos.

This explains why Japan wants to store neutrinos, and the reason for choosing 1000 meters underground is because there are many particles in the cosmic rays, underground can be isolated from the interference of particles on the ground.

The Japanese team conducted the “Kamioka Nuclear Decay Experiment” at 1000 meters underground until February 1987, when the Japanese Kamioka detector detected neutrinos generated by the supernova 1987A explosion in the Large Magellanic Cloud, which gave Japan great encouragement.

Neutrinos Suggest Solution to Mystery of Universe's Existence | Quanta  Magazine

So Japan has increased the research on neutrino, the ultra-pure water storage capacity from a few thousand tons to 50,000 tons, which 50,000 tons of ultra-pure water in 1996 officially put into use, the results of the detection of Japan won two Nobel Prizes.

The study of neutrinos is of great significance.
Neutrinos have a very small mass, almost zero, and can pass freely through any material without reacting with it, but this does not affect the penetrating power of neutrinos at all.

Not only that, but neutrinos can easily pass through rocky planets like Earth. Since its discovery, the neutrino has been considered one of the most fundamental particles in the vast universe. Throughout the universe, neutrinos are usually produced by nuclear reactions in stars, supernovae or cosmic rays hitting atoms.

Therefore, neutrinos may contain the mysteries of the universe, and the study of neutrinos is of great importance to the origin and evolution of the universe and the formation of the grand structure of the universe, but neutrinos are difficult to detect and we know very little about this particle at present.

Neutrinos could shed light on why the Universe has so much more matter than  antimatter

Nowadays, neutrino research is one of the hottest directions in physics. Neutrinos can be used not only in astronomical research, but their powerful penetrating power and speed close to the speed of light determine that they can improve the speed and efficiency of communication propagation nowadays.