This article is from the April 2010 issue of Beyond Borders: A Barrick Gold Report on Responsible Mining.
At the Pueblo Viejo project in the Dominican Republic, one of the most ambitious environmental clean-up efforts in recent mining history is underway. When the former Rosario Dominicana mine shut down its operations in 1999, proper closure and reclamation was not undertaken. The result has been a legacy of polluted soil and water and contaminated infrastructure.
Barrick acquired the property in 2006 as part of the Placer Dome acquisition. Today, what was once a hazardous area has been transformed into a safe and busy construction site, as some 4,500 employees and contractors converge to build the new Pueblo Viejo.
The clean-up is also creating a healthier living environment for nearby residential communities that have also been affected.
A Partnership Approach
Responsibility for the clean-up is shared between Pueblo Viejo Dominicana Corp. (PVDC), a company jointly owned by Barrick (60%) and Goldcorp (40%), and the Dominican government. A special lease agreement (SLA), which set out the terms for both parties, was ratified by the Dominican National Congress and President Leonel Fernandez in November 2009. The agreement stipulates that environmental remediation within the mine site and its area of influence is the responsibility of the company; the Dominican government is responsible for historic impacts outside the project development area.
Earlier in 2009, President Fernandez and Barrick’s president and CEO, Aaron Regent, met in Santo Domingo to discuss the estimated $3 billion project, which represents the largest foreign investment in the country’s history. They expressed a shared desire to significantly improve local living conditions and conduct the clean up to international standards. It was agreed that Barrick’s experts would manage the clean-up effort on the government’s behalf.
Extensive expert studies of the area documented the effects of years of unchecked acid rock drainage (ARD ) at the site and in the surrounding area. The findings included heavy metal concentrations, acidity and sediment in local waterways. The primary sources of soil and water contamination were the historic open mine pits, waste rock piles and tailings storage areas.
The Arroyo Margajita River winds through the hills near the site. Dubbed the “coca-cola river” by locals because of its dark hue, this waterway absorbed the brunt of the acid rock drainage from the former mine. Remediation of the waterways that surround the site and the stabilization of historic tailings dams have been key concerns for the company and the government.
Financing the Clean-up
While the company bears responsibility for remediation within the mine development area, sources of ARD from small pits and rock waste dumps exist outside these boundaries and continue to affect water systems. Although financial responsibility for these areas resides with the government, the company agreed to donate up to $37.5 million, or half of the government’s total estimated cost of $75 million for their clean-up responsibilities. PVDC will also finance the remaining amount, allowing the government to repay the debt with revenues generated by the mine.
Acting as agents for the government, the company is implementing an action plan to install infrastructure for capturing ARD water and to reinforce the Mejita dam. PVDC will also build a state-of-the-art water treatment plant at Pueblo Viejo, larger than would otherwise be required for mining operations. This will make it possible for the plant to capture and process water in both the company’s and the government’s areas of responsibility. Currently, company environmental experts are conducting regular sampling of surface and ground water to gauge acidity levels. The goal is to reduce acidity levels and allow streams to recover, giving nearby communities access to better quality water.
Today, construction of Pueblo Viejo is proceeding on schedule and is over 20% completed. However, before the building phase could commence, the land had to cleared and restored. In 2008, the complex, laborious task began.
A team was created comprising Barrick employees, hazardous materials experts and new employees hired locally and specially trained for the operation. Their task was to dispose of hazardous materials and waste and reclaim the contaminated soil. Over a thousand samples were taken to define soil in the area into different categories and determine future treatment and landfill options.
Buildings on the property contained different types of hazardous waste that had to be categorized and disposed of in a safe manner.
“We have now torn down all the old buildings and cleaned up all the waste materials inside our project area,” explains Méjico Angeles-Lithgow, Pueblo Viejo’s director of government and regulatory affairs. “Contaminated waste which couldn’t be reclaimed will be taken to special depots in the United States and Canada.” To date, more than 130,000 m3 of soil have been removed to rid the ground of contaminants.
Bioremediation, a process that uses microorganisms to return altered land to the natural environment, was successfully introduced at the site. To date, 70,000 m3 of hydrocarbon contaminated soils have been successfully treated.
Local residents were hired and trained to identify and transplant thousands of plants from the impacted area. A reforestation program around mine property has also been underway, planting about 20,000 native trees a month.
Construction Now Underway
With construction of the mine proceeding full steam ahead, the once toxic site is now unrecognizable. Structural steelwork for new mine infrastructure is underway, the grinding mill has been built, and a new mine camp for 2,500 employees is operational. Construction is expected to be completed in the last quarter of 2011, when mineral extraction will begin.
For Bill Williams, Barrick’s vice president environment, restoring the disturbed environment at Pueblo Viejo back to health is the first step toward industry-leading environmental management over the life of the mine. Pueblo Viejo will operate to Barrick’s environmental standards, consistent with ISO 14000, the international environmental management standard.
“Going forward, we aim to make Pueblo Viejo a model of environmental responsibility within the mining industry,” says Williams.
Local Employment and Training
A bout 4,500 employees and contractors are working at the site today. More than 80% of the workforce is Dominican. Approximately 3,000 people have taken part in training programs.
Investments to date include education, nutrition, health and infrastructure programs, as well as initiatives to improve the productivity of local farmers and economic prospects for women.
Nancy White is Barrick’s director of communications for responsible mining. She may be reached at 416-309-2143.