of tailings. However, it is typically impossible to restore groundwater quality to its initial state when uranium recovery is done in situ or to totally contain all of the leachate material (Davis and Curtis, 2007). However, most uranium mining wastes in the United States have come from conventional mining operations, both surface and underground, from 1957 to 1989 (World Nuclear Association, 2007).
Uranium recovery in Russia and the former Soviet Union is done through both ISL and conventional mining. In the early 1990s, approximately 38 percent of uranium mined in the former Soviet Union came from ISL (Bradley, 1997).
For the Russian Federation, on the basis of metric tons of uranium in the concentrate, the distribution of the 3,281 metric tons of uranium obtained from conventional mining and ISL in 2004 was as follows (OECD-IAEA, 2005):
Open-pit and underground mining: 2,880 metric tons
ISL: 200 metric tons
Heap leaching: approximately 190 metric tons
In-place leaching (slope or block): 11 metric tons
During the workshop, it was stated that Russia intends to increase its production of uranium from 4,900 metric tons in 2010 to 18,000 metric tons by 2020 (Shatalov, 2007). Conventional mining of uranium has left large areas (several square kilometers) of land contaminated with mill tailings. For example, Uzbekistan has 2.8 km2 of such land; Tajikistan, 3 km2; Kyrgyzstan, 6.5 km2; Kazakhstan, 2.5 km2; and Russia, 2 km2 (Karamushka and Ostroborodov, 2008). As of 1990 the former Soviet Union had generated approximately 5 billion metric tons of mill tailings (Bradley, 1997).
The major source of uranium for the Soviet Union was the mines, collectively now known as Wismut, in Saxony and Thuringia in the German Democratic Republic (GDR). More than 400,000 people have worked at Wismut, with peak employment reaching 130,000 people in 1950. The total output of the mines was 231,000 metric tons, with peak production of 7,100 metric tons in 1967. During the Cold War, very little was known about uranium mining in the Soviet Union. However, in 1954 a joint Soviet-GDR company, Wismut, was formed. After German reunification, production ceased and Wismut became the property of the Federal Republic of Germany. When this transfer occurred, much previously unavailable data became public. Wismut is responsible for the remediation