LIMA, Peru (AP) -- The long-contested expansion of Peru's main natural gas field has won final regulatory approval despite U.N. concerns that it could endanger Amazon tribes living in voluntary isolation in pristine jungles.
The Camisea project, located just 60 miles (100 kilometers) from Peru's famed Machu Picchu ruins, has faced fierce opposition from environmental groups since it began in 2003, but strong backing from Peru's political leaders as a vital economic lifeline.
The approved expansion overlaps with an indigenous reserve populated by about 1,100 people, including an estimated 100 who avoid contact with the outside world.
Peru's Ministry of Mining and Energy gave the expansion a green light Monday, approving an environmental impact statement as the nation was focused on a World Court verdict that resolved a maritime dispute with Chile.
Environmentalists, anthropologists and the U.N.'s Committee on the Elimination of Racial Discrimination had objected that the project could threaten indigenous groups by exposing them to diseases for which they have no natural defenses.
In December, the U.N.'s special rapporteur for indigenous rights, James Anaya, visited Camisea, which is run by a consortium led by Argentina's Pluspetrol S.A. and that includes the U.S. company Hunt Oil Co. and the Spanish concern Repsol YPF S.A.
Anaya urged an exhaustive study of the expansion's effect on indigenous communities in the concession as well as consultation with them before proceeding with a $480 million exploration phase.
"None of this was done. There has not even been a serious study about the health of the population in the area since 2003," said Vanessa Cueto, a lawyer for the environmental group Environmental Law and Natural Resources.
The expanded Camisea project will now overlap with about 400 square miles (1,036 square kilometers) of the indigenous reserve in one of the world's most biologically diverse rainforests, where the natives live primarily off fishing and hunting.
The environmental impact study says there could be Indians living in voluntary isolation in an area comprising just 30 square miles (8,000 hectares) of the overlapping area and says no drilling will occur there.
But Paulo Vilca, who resigned as deputy culture minister for indigenous rights in July over the issue, says that claim has no basis because the government has never done a study to determine where the Indians live. Vilca was one of three ministry officials to step down or be forced out over objections to the expansion, which President Ollanta Humala has firmly supported.
Peru has an estimated 12 trillion cubic feet (340 billion cubic meters) of proven natural gas reserves in two concessions held by the Pluspetrol-led group.
Most of it lies within the 5,500-square-mile concession where the expansion is occurring. The concession, known as Lot 88, already supplies Peru with half its electricity as well as gas for industry, motor vehicles and some homes. The gas from Camisea's other lot is exported.
A Pluspetrol spokesman in Lima, Carlos Naveda, said the company had no immediate comment on its expansion plants. The consortium has said exploration could take at least 15 months.
The Associated Press sought an interview with the current deputy minister for indigenous rights, Patricia Balbuena, but she had not responded to email and telephone requests.
The project is meant to include 13 wells, 1,800 workers, more than 3,000 underground seismic blasts and 90 helicopter landing sites, according to the environmental impact statement.
Prior to his resignation last year, Vilca produced a highly critical report that said the expansion would "severely affect the life and health of the population in isolation, which is especially vulnerable" in its ability to resist disease. The report was almost immediately removed from his ministry's website.
Flu and diahrrea have killed at least 37 people of the Machiguenga tribe over the past decade in the reserve, according to official figures, and in the 1980s, Royal Dutch Shell workers caused an epidemic there that killed some 300 Nahua natives. The other main indigenous group in the reserve is the Nanti.
The estimated 100 people in voluntary isolation are from the Nanti and Kirineri people. In the Americas, Peru, Ecuador, Colombia, Venezuela, Brazil and Paraguay all are known to have such groups.
Anthropologist Beatriz Huertas, Peru's top expert in the field, says it takes about 150 years for indigenous groups, after they have made "initial contact" with outside societies, to develop immune responses adequate to resist introduced diseases.
"A simple flu can lead them to extinction," she said.
Associated Press Writer Frank Bajak contributed to this report.
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