An Andean woman drinks water from the Perol lake using her hat during a protest against Newmont Mining's Conga project at Peru's Cajamarca region June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY) 

Andean people protest against Newmont Mining's Conga project during a march along the Perol lake in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Picture taken June 17, 2013. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY BUSINESS) 

An Andean man talks to a police officer (L) during a march against Newmont Mining's Conga project in Peru's Cajamarca region June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY) 

An Andean man smokes a cigarette while resting during a march against Newmont Mining's Conga project, along Perol lake in Peru's Cajamarca region June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT BUSINESS) 

Police officers stand guard near one of the entrances to Newmont Mining's Conga project before a protest in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT BUSINESS) 

Andean people remove rocks from reservoirs near a dam, built by Newmont Mining's Conga project near Perol lake, during a protest in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT BUSINESS) 

Andean people set fire to areas surrounding a dam, built by Newmont Mining's Conga project near the Perol lake, during a protest in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT BUSINESS) 

A destroyed sign, which indicated the location of Newmont Mining's Conga project, is seen in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT BUSINESS) 

An Andean woman drinks water from the Perol lake using her hat during a protest against Newmont Mining's Conga project at Peru's Cajamarca region June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY) 

Andean people march during a protest against Newmont Mining's Conga project, along the Perol lake in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY) 

An Andean woman sits on a horse as she takes a break during a march against Newmont Mining's Conga project in Peru's Cajamarca region June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY) 

Jose Rojas, an Andean man, flavours coca leaves with lime as he chews on the leaves while resting during a march against Newmont Mining's Conga project, along the Perol lake in Peru's Cajamarca region June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY) 

Andean people march during a protest against Newmont Mining's Conga project, along the Perol lake in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY BUSINESS) 

Andean people march during a protest against Newmont Mining's Conga project, along the Perol lake in Peru's region of Cajamarca June 17, 2013. Thousands of opponents of a $5 billion gold project of Newmont Mining circled a lake high in the Andes on Monday, vowing to stop the company from eventually draining it to make way for Peru's most expensive mine. Lake Perol is one of several lakes that would eventually be displaced to mine ore from the Conga project. Water from the lakes would be transferred to four reservoirs that the U.S. company and its Peruvian partner, Buenaventura, are building or planning to build. REUTERS/Enrique Castro-Mendivil (PERU - Tags: CIVIL UNREST ENVIRONMENT SOCIETY BUSINESS)