Depleted uranium hexafluoride, or uranium tailings are a side produce to the uranium enrichment process in making fuel for nuclear power stations. Several thousand tons of depleted uranium hexafluoride has piled up in Russia and in other countries and there are no long term plans for their further use, meaning uranium tailings are classifiable as radioactive waste. According to the Russian law On Atomic Energy Use (November 21st 1995 No. 170 – FZ) radioactive waste is defined as those nuclear and radioactive substances for which no further use is envisioned.
Russian legislation forbids the import of pure radioactive waste. Nevertheless, uranium tailings are imported to Russia via a variety of contracts between Russian atomic energy agency Rosatom and the German-British-Dutch enrichment giant Urenco, the French Eurodif enrichment concern, and others. The waste is delivered to Russia via the Port of St. Petersburg and is sent for storage to Seversk, near Tomsk, Angarsk, near Irkutsk, Zelenogorsk, near Krasnoyarsk and Novouralsk, near Yekatrinburg.
As per the contract between Urenco and Tekhsnabexport (Tenex) - Russia’s nuclear fuel producing giant – a portion of the tailings are re-enriched. But some 90 percent of them remain behind in Russia, meaning only 10 percent of them are sent back to their countries of origin in enriched form.
However, if western European experts’ assessments are accurate, there are also contracts dictating that 100 percent of the radioactive waste remains in Russia.
For the past 10 years as a result of re-enrichment of uranium tailings in Russia, some 560,000 to 720,000 tons of new radioactive waste resulting from Urenco enrichment have been shipped to Russia.
The storage costs for such radioactive waste in various countries ranges from 2 million to 22 million dollars per thousand tons. Were Urenco and Eurodif to store their tailings in their respective countries, their production costs would consequently increase by five times.
The current contracts between Rosatom and the western enrichment firms are valid until 2009 for Urenco and 2014 for Eurodif.
Russia is the only country in the world that accepts depleted uranium hexaflouride from abroad on an industrial scale.