The International Olympic Committee praised construction work for the Sochi Winter Games after an inspection of the site Wednesday, and Prime Minister Vladimir Putin promised to respect the environment.
But environmental groups complained that their advice was being ignored and warned of dangerous consequences.
"Progress is very significant," said Jean-Claude Killy, chairman of the IOC commission that is monitoring the work in Sochi.
He said IOC inspectors were "on most accounts very satisfied" with what they saw on the visit.
The committee was "deeply impressed" by attention to the environment, the 24-hour workdays, the government's focus on the project, and "everything we have seen," he said.
Putin, speaking during a teleconference call, touted the Olympic project for giving "unprecedented development" to southern Russia and assured Killy that Russia was ready to listen to outside advice and comply with recommendations.
"Protection of the environment is one of our priorities," Putin added. "We are trying to not only conserve nature, but to restore what has been lost because of human activity."
While Putin stressed the government's environmental awareness, conservation groups said their advice has been ignored in Sochi, leading to the complete loss of important nature areas. Greenpeace and the World Wildlife Fund have stopped working with the Sochi 2014 Organizing Committee and Olimpstroi, the state corporation overseeing construction, "until there is a dialog at the highest level with the authorities" to guarantee the thorough monitoring of all sites and adequate compensation measures, said WWF deputy director Pyotr Gorbunenko.
He said IOC inspectors might appreciate seeing truck tires washed, but they do not see that dirty construction water simply flows into the nearby Mzymta River.
"Of course there are things to show on these commission visits, but at what cost do these things come?" Gorbunenko said.
Last month, the WWF paid for laboratory tests of water fr om the Mzymta River and found that concentrations of arsenic, phenols and oil exceeded maximum permissible levels by 300 percent, 3,500 percent, and 6,000 percent, respectively, he said.
"Nobody is monitoring the sources of this pollution," Gorbunenko said, adding that monitoring was needed to fulfill the environmental goals announced by Putin.
He warned that water from the Mzymta River could run into drinking water supplies.
Mountain tests were taken around Krasnaya Polyana and Esto Sadok, wh ere Rosa Khutor and Gazprom are building hotels and sports venues.
Rosa Khutor, a major resort developed by Vladimir Potanin's Interros, is one of the projects that will be completed this year, Putin said. Others include the new airport and seaport, both built by Oleg Deripaska's Basic Element, and two power stations, he said.
Olimpstroi, meanwhile, is considering suing Basic Element subsidiary BasEl Aero for 5 million rubles ($173,000) for not finishing the airport on time, Interfax reported late Tuesday. The airport was supposed to be finished by March 31.
The federal budget is allocating 29.7 billion rubles to Olympic development, while private investment is to amount to 29.1 billion rubles.