"Undok Salt" produced there tells about the devoted efforts made by the peerlessly great men for the development of the country's salt industry.

In April Juche 99 (2010) Chairman Kim Jong Il visited the education science exhibition at Kim Il Sung University. There he examined an illustration for developing underground ultra-saline water resources and expressed his great satisfaction, saying that it is a good idea for realizing his plan.

Later, he took a step to confirm the deposits of underground ultra-saline water and its positions on the west coast and other parts of the country.

Supreme Leader Kim Jong Un acquainted himself with the development of underground ultra-saline water on several occasions and gave precious instructions.

In 2013, the Supreme Leader dispatched a powerful sci-tech group to speed up the development work and provided an example in establishing the method of salt production based on underground ultra-saline water.

In May 2016, he went round the salt production site and expressed his great pleasure over the heaps of salt produced from underground ultra-saline water, saying he felt as if they were a mountain of white gold. And he added that it would be good to call it "Undok Salt" in the meaning of the Chairman's benefit.