Int. J. Environ. Res. Public Health 2009, 6 175 Union – Russian collaboration “South Ural Contamination” (SUCON, 1996-1999). This paper strives to present an overview of activities at the Mayak Production Association (Mayak PA) and the subsequent quantification of health effects on specific local populations caused by discharges of radioactive waste into the environment. Research into the radiological consequences of activities at the Mayak PA has been a focus area for cooperation between scientists from the Russian Federation and scientists from Europe, the USA and Japan. Citations made in the paper are intended to give a comprehensive, though not exhaustive, basis for further reading about this topic. Construction of the Mayak PA started in the Chelyabinsk province, close to the town of Ozyorsk (Chelyabinsk-65), in May 1946. The site lies between Yekaterinburg (Sverdlovsk) and Chelyabinsk, east of the Ural Mountains: 55º44′ N 60º54′ E. The Mayak Production Association covers about 200 km2 and incorporates the Mayak Chemical Combine, the Chelyabinsk-60 Research Facility and the unfinished South Urals Nuclear Power Plant (NPP). The Mayak PA lies in South Ural, about 1,400 km east of Moscow, close to the River Techa, which forms part of the Techa-Iset-Tobol-Irtysh-Ob river system that eventually drains into the Kara Sea (Figure 1). Today, the Mayak PA facilities include two reactors used for plutonium (238Pu) and tritium production; fuel reprocessing facilities; a plutonium processing, finishing, and component manufacturing plant (Plant 20); mixed-oxide (MOX) fuel fabrication plants; fissile material storage and nuclear waste treatment facilities. The Mayak PA had some 15,000 employees in 2000 according to Russian media. Two heavy water reactors (OK-190 and OK-190M) were shut down in 1965 and 1986, respectively. Weapons-grade plutonium production was stopped in 1987. All five of the plant's uranium-graphite plutonium production reactors (A, IR, AV-1, AV-2 and AV-3) were permanently shut down between 1987 and 1991. Mayak’s activities are currently believed to include reprocessing spent nuclear fuel (SNF), conversion of weapons-grade plutonium into MOX fuel, production of PuO2 and UO2, production of radioisotopes and the manufacture of electrical devices as well as control and monitoring equipment for pipelines. 1.1. The Mayak Facilities The first uranium graphite reactor (“A-plant”) at the plant became operational in June, 1948; the first batch of plutonium concentrate being produced by the radiochemical facility (“B-plant”) in February, 1949. As of August, 1949, the on-site chemical/ metallurgical facility (“V-plant”) had converted the concentrate into weapons’ grade plutonium. The facility then expanded, consisting of seven military nuclear reactors by 1987, at which time weapons’ grade plutonium production ceased. Creation of a nuclear weapon industry raised the problem of radiation safety for the workforce and people living in the vicinity of the plant and general sanitary standards and regulations were adopted in 1948. The Mayak PA was the first production reactor complex built in Russia and has historically been responsible for significant radioactive contamination of the surrounding region. One important contemporary activity at the Mayak PA is the production of radioisotopes for industrial and medical purposes. Two tritium-producing reactors (Ruslan and Lyudmila: Plant 37) are still in operation; the heavy-water moderated reactor Ruslan was put into operation at the end of 1940s to produce tritium and isotopes for nuclear weapons. It was redesigned towards the end of 80s to a light-water reactor with a capacity of ~1,000 MW. Lyudmila (LF-2) is a ~1,000 MW heavy-water reactor that also produces tritium and various isotopes. Both these reactors have cooling systems