In Ningyo-toge, an outcropping of uranium ore was found for the first time in Japan.

After the discovery of the outcropping, “Ningyo-toge Office” of Atomic Fuel Corporation (presently “Ningyo-toge Environmental Engineering Center” of JAEA) newly opened for uranium exploration in 1957. Since then, research and development of technology have been carried out for uranium exploration, mining, milling and refining and so on. After uranium exploration was terminated in 1987 around Ningyo-toge, the main activities of the Ningyo-toge Environmental Engineering Center have shifted to maintenance and management of facilities, including reclamation activities at the waste rock pile site and mill-tailings dam.

In the meantime, technology for uranium enrichment, refining and conversion for the production of UF6 had been developed since the late 1970’s.

As for the uranium enrichment technology, it is worth mentioning that the Uranium Enrichment Demonstration Plant (DP) operated continuously for 13 years from 1988 to 2001. This plant, developed and put into practical use by our country from scratch, terminated its operation with its reliability confirmed. The accumulated expertise obtained during its operation has been transferred to and utilized by the uranium enrichment facility run by Japan Nuclear Fuel Limited (JNFL) at Rokkasho-mura, Aomori Prefecture.

In recent years, development of technologies has been carried out for related fields. Included among the fields are, recovery of uranium remaining in piping or in the interior of the uranium enrichment equipment, decontamination, volume reduction and recycling of radioactive waste. Also, the “Decommissioning Engineering System” has been developed to organize above-mentioned technologies systematically.

Our projects have proceeded for as long as half a century since the discovery of the uranium outcrop in November 1955, thanks to the support and cooperation of local citizens and authorities. We, Ningyo-toge Environmental Engineering Center, give safety our highest priority and work hand in hand with the local citizens as in the past.

Also, information disclosure is actively promoted for the transparency of our projects.