American officials said privately that the responsibility belonged to the Central Asian countries. The United Nations has not given Maili Suu the priority necessary to provoke a coordinated response. The place looks benign. The waste is kept in large reservoirs that were covered with a layer of clay and two feet of sand and gravel as they were filled. Those buried reservoirs now form gently rolling mounds and slopes, with a fuzz of grass.
Cattle sometimes graze on the hills, and children play there.
Most of the barbed-wire fencing put up to keep out people and animals has been dismantled by locals for use in penning their livestock. The city of Maili Suu has 24,000 residents and stretches for seven miles along the river. Dr. Nemat Mambetov, the region's epidemiologist, said that he had tracked increased incidences of cancer and blood diseases in Maili Suu since 1982, but that no direct relationship to the waste had been established. Tons of material spilled into the river and washed down in 1958 when a wall at one reservoir gave way. The Soviets tried to keep the breach secret, but Dr. Mambetov said he believed that the radioactivity in town had come from that incident and smaller spills over the years.