The bulldozer driver smiled and shouted "Come back again!" as his machine pushed more dirt onto the new embankment.
But in Maili Sai, where the bulldozer was shoring up a radioactive waste storage site which was almost swept into a nearby river by recent mudslides, coming back again hardly seemed like a sensible idea.Down the hill in a shabby factory where uranium was once processed, Soviet-era propaganda boards featuring broadchested men and strapping women still exhort workers to greater productivity.
Maili Sai, a town of 30,000, lies in Kyrgyzstan in former Soviet Central Asia. Set amidst foothills of the Tien Shan mountains, it was once considered a wonderful place to live, with supplies specially shipped from Moscow.
"When I came in the 1970s, we had theater and the shops were full," recalls Dr. Valentina Roslyakova, head doctor at the Maili Sai hospital. "There was black caviar, red caviar and 20 types of cookies. We had excellent education and health care."
All that vanished with the demise of the Soviet Union, and now Maili Sai has to come to terms with the reason for its once-favored status: The town was built after World War II as a center for uranium mining and processing. The town's population was mostly Russian and Soviet German.
Uranium mining and processing began here in 1947 and continued until 1967, by which time the mines had been closed. But radioactive waste remained, buried in 23 sites around the town or even left in the open. When the town was struck by a huge mudslide this spring, people began to wake up to the potential disaster here.
The former uranium processing plant narrowly escaped being hit by the mudslide, which occurred when a vast section slid off the opposite hillside, cutting the town in two and damming the river so that hundreds of people had to be evacuated.
"Everybody's afraid it's only a matter of time before mudslides upset the waste sites," says Wakhidzhan Ergashev, the regional official responsible for emergencies. "Then it will all go into the river and that flows straight down into Uzbekistan."
The Ferghana valley, one of the most densely populated areas of the former Soviet Union, lies in the Republic of Uzbekistan, just downriver from Maili Sai. There the Maili Sai river joins the Syr Darya, one of Central Asia's chief rivers, whose water is used extensively for irrigation and drinking.
International organizations have become concerned about the problem since impoverished Kyrgyzstan simply has no money to spare for nuclear cleanup operations.
In Soviet days everything about Maili Sai was a closely guarded secret. Documents relating to the uranium industry there were kept in Moscow or in Leninabad, which now lies in another former Soviet republic, Tajikistan.
Getting access to this crucial information has proved difficult. As a result, no one in Maili Sai is sure just what's buried in the waste sites or how dangerous it is.
If the uranium processing plant produced enriched uranium, the buried waste could be "yellow cake," highly radioactive and soluble in water - the worst possibility if any is washed into the river.
Red Cross employees who visited the area recently found radiation levels, according to Ruybuk Abdyldayev, deputy director of the Institute of Oncology and Radiology in the Kyrgyz capital, Bishkek.