After more than two decades of drilling in Antarctica, Russian scientists have reached a gigantic freshwater lake hidden under miles of ice for about 20 million years - a pristine body of water that may hold life from the distant past and clues to the search for life on other planets.

Finally touching the surface of Lake Vostok, the largest of nearly 400 subglacial lakes in Antarctica, is a major discovery avidly anticipated by scientists around the world.

Controversy

The drilling project has been opposed by some environmental groups and scientists who have argued that hot-water drilling would do less environmental damage. The Russians explained that hot-water drilling required more power than they could generate at their remote camp.

Scientists of the United States National Research Council have taken the position that it should be assumed that microbial life exists in Lake Vostok and that after such a long isolation, any life forms in the lake require strict protection from contamination.

Sediments on its floor should give clues to its long-term climate, and isotopes in its water are expected to help geologists determine how and when subglacial lakes such as Lake Vostok form. Meticulously documented decontamination procedures will be required to establish the credibility of the scientific data obtained.
The original drilling technique employed by the Russians involved the use of Freon and kerosene to lubricate the borehole and prevent it from collapsing and freezing over; 60 tons of these chemicals have been used thus far on the ice above Lake Vostok.

Other countries, particularly the United States and Britain, have failed to persuade the Russians not to pierce to the lake until cleaner technologies such as hot-water drilling are available.
Though the Russians claim to have improved their operations, they continue to use the same borehole, which has already been filled with kerosene. According to the head of Russian Antarctic Expeditions, Valery Lukin, new equipment was developed by researchers at the St. Petersburg Nuclear Physics Institute that would ensure the lake remains uncontaminated upon intrusion.

Lukin has repeatedly reassured other signatory nations to the Antarctic Treaty System that the drilling will not affect the lake, arguing that on breakthrough, water will rush up the borehole, freeze, and seal the chemical fluids out.

Environmentalist pressure groups remain unconvinced by these arguments.

The Antarctic and Southern Ocean Coalition has argued that this manner of drilling is a profoundly misguided step which endangers Lake Vostok itself and also other subglacial lakes in Antarctica (which some scientists are convinced are inter-linked with Lake Vostok).

The coalition has asserted that "it would be far preferable to join with other countries to penetrate a smaller and more isolated lake before re-examining whether penetration of Lake Vostok is environmentally defensible. If we are wise, the Lake will be allowed to reveal its secrets in due course."