Newmont Mining Corporation

Adapted from Beyondthemine.com

Water quality and supply have been the primary issues of concern for nearby communities of the Minera Yanacocha operation, as they rely on water for farming and agriculture. To address this, our operation built a reverse-osmosis plant and upgraded the existing acid-water treatment plants to ensure that only high-quality water leaves the property.

Additionally, Yanacocha transformed the mined-out San Jose pit into a $25 million reservoir that stores 1.3 billion gallons (5.9 million cubic meters) of water. Today, the San José Reservoir provides a long-term supply of clean water for local agricultural users.

According to mine closure plans, the pit was slated to be filled and re-vegetated. However, recognizing the potential to address local water needs, Yanacocha consulted surrounding communities and developed a plan to convert the pit into a reservoir to store water in the rainy season and make it available to agricultural users during the dry season.

"The San José reservoir is another example of how Yanacocha is working with local communities to creatively leverage our operations to deliver sustainable benefits to our neighbors," said Carlos Santa Cruz, vice president, South American operations. "We've taken what many would have considered an environmental liability and turned it into a valuable environmental asset."

Adapted from Beyondthemine.com
Yanacocha is examining the reclamation covers it uses to prevent rainwater from infiltrating into waste rock storage areas and heap leach facilities. Reclamation covers are comprised of topsoil, re-compacted waste rock, subsoil, limestone, geosynthetics or a combination of these materials.

Over time, plants grow on the surface of these covers, creating an additional barrier. Water that permeates the cover and contacts waste rock and heap leach areas requires treatment before it can be discharged safely back into the environment. Therefore, reducing the amount of water that penetrates the covers can reduce both the amount and expense of treated water.

Rather than relying solely on mathematical modeling to make these predictions, the team is using a technology known as a lysimeter to measure water runoff and infiltration. The team installed a 250-meter by 350-meter lysimeter device on the top of a reclaimed waste rock storage facility to continuously measure water runoff and seepage. Collecting more accurate and real-life data greatly enhances the mine's ability to design reliable water management systems, and more accurately communicate with nearby ranchers and farmers about the impacts to local water supplies and water quality after mine closure.

Last results indicate the water infiltration models tend to over-predict the amount of water that penetrates our reclamation covers, and that infiltration rates are between 5 percent to 22 percent. As a result, it may be possible to further optimize the design and construction of reclamation covers while still effectively limiting water infiltration.
By proactively looking at these issues while the mine is operational, the site will be better positioned to prepare for closure. As more data becomes available from the Yanacocha study, other Newmont sites in high rainfall areas, such as Batu Hijau and Ahafo, could use the information to adjust estimates of water infiltration and the associated reclamation costs to effectively manage impacted water from reclaimed facilities.

Adapted from Beyondthemine.com

Thousands of acres (hectares) of land around Minera Yanacocha's operations have been planted with trees under a program to reverse historical, widespread deforestation in this area of northern Peru. The mountainous region has suffered from centuries of subsistence agriculture. Traditional land practices and overgrazing of animals have significantly changed the rolling landscape, leaving the land unproductive and virtually barren of trees. Some 14.8 million acres (6 million hectares) of land stretching north from Lima were impacted as well as nearly 2.5 million acres (1 million hectares) in the Cajamarca region.

Newmont is working with the Cajamarca-based Association for Forest Research and Development, aid agencies and academic institutions to develop and execute ambitious reforestation programs. Reforestation has clear environmental benefits. The young trees will support biodiversity by providing habitats for animals and protect against soil erosion. They also will absorb carbon dioxide from the atmosphere, helping to offset climate change.

Tree planting also can have important economic consequences. It can provide sustainable employment in planting, tending, harvesting and manufacturing, providing valuable jobs beyond the lifespan of the mine. To date, Minera Yanacocha has reforested 13,296 acres (5,381 hectares).

Yanacocha is examining the reclamation covers we use to prevent rain water from infiltrating into waste rock storage areas and heap leach facilities. Reclamation covers are comprised of topsoil, re-compacted waste rock, subsoil, limestone, geosynthetics, or a combination of these materials.

Over time, plants grow on the surface of these covers, creating an additional barrier. Water that permeates the cover and comes in contact with waste rock and heap leach areas requires treatment before it can be discharged safely back into the environment. Therefore, reducing the amount of water that penetrates the covers can reduce both the amount and expense of treated water.

Rather than relying solely on mathematical modeling to make these predictions, the mine team is using a technology known as a lysimeter to measure water runoff and infiltration. The team installed a 250-by-350 meter lysimeter device on the top of a reclaimed waste rock storage facility to continuously measure water runoff and seepage. Collecting more accurate and real-life data greatly enhances our ability to design reliable water management systems and more accurately communicate with nearby ranchers and farmers about the impacts to local water supplies and water quality after mine closure.

Early results show the water infiltration models tend to over-predict the amount of water that penetrates our reclamation covers.Less infiltration through these covers than predicted means that it may be possible to further optimize the design and construction reclamation covers while still effectively limiting water infiltration.

By proactively looking at these issues while the mine is operational, we will be in a better position to prepare for closure. As more data becomes available from the Yanacocha study, other Newmont sites in high rainfall areas, such as Batu Hijau and Ahafo, could use the information to adjust estimates of water infiltration and the associated reclamation costs to effectively manage impacted water from reclaimed facilities.

Newmont's Minera Yanacocha became the first large-scale gold company to obtain ISO 14001 international certification of its operations as part of our commitment to responsible environmental stewardship.

Most companies only certify specific processes or portions of their operations. To certify the entire operation, Yanacocha staff worked diligently during the two-month certification process to comply with necessary requirements, which included thoroughly analyzing each of our processes and training our work force of 10,000.

To maintain compliance, the mine will be audited four times during the next two years.

"We are proud of our complete ISO certification because it demonstrates our commitment to leadership in environmental management," said Luis "Tito" Campos, environmental and social responsibility manager. "The certification verifies that Yanacocha has complied with the most rigorous international levels of environmental stewardship."

The International Cyanide Management Institute certified Newmont's Yanacocha mine in Peru as being compliant with the International Cyanide Management Code (Code). The Code is a voluntary industry program for companies involved in the production of gold using cyanide and companies producing and transporting this cyanide. The operation must be re-audited every three years hereafter to maintain compliance.