Mercury occurs naturally in the earth’s crust. It is particularly concentrated in areas associated with relatively recent volcanic activity, high heat flows, and plate tectonic boundaries. For example the western United States, particularly the basin and range province, which includes portions of California, Arizona, Nevada, Utah and Idaho, includes significant areas of natural mercury occurrence.

Natural processes such as weathering of rock, vaporization from soil, wildfires and off-gassing of the world’s oceans, emit mercury into the atmosphere. According to the U.S. Environmental Protection Agency (USEPA) and other scientific sources, one-half of the mercury emitted into the environment each year is from natural processes. Combustion of coal is the largest single human-generated source of mercury air emissions. Mining is a relatively minor source of mercury air emissions on a global and a national level.

Once released into the atmosphere, mercury may be transported great distances from its original source. For example, according to USEPA, half of the human-generated mercury that is deposited in the western U.S. comes from industrial sources in Asia.

Mining operations in the state of Nevada account for about one percent of U.S. mercury air emissions. According to USEPA’s TRI data, which includes gold mining data, Nevada ranks eighth among the states in mercury air emissions, behind California. Many gold mines do not emit mercury to the air.

Efforts, To Date, In Voluntary Mercury Reduction

In 2001, the USEPA and the Nevada Division of Environmental Protection began a dialogue with major gold mining companies that operate mines in Nevada, concerning mercury emissions controls. Rather than engage in a lengthy and costly rule-making process to achieve Maximum Achievable Control Technology (MACT), all parties, including Barrick agreed to a Voluntary Mercury Reduction Program (VMRP). The voluntary program has achieved an overall reduction of about 70 percent in mercury emissions by the group of participating companies.

The Barrick Commitment

Even prior to the commencement of the Voluntary Mercury Reduction Program, Barrick had installed state-of-the-art mercury reduction controls on most of its mercury emission sources. For example, the mercury controls on Goldstrike’s new $330 million roaster, are more than 99.5 percent efficient. Barrick has also installed a new mercury scrubbing system on the mine’s carbon kiln circuit.

At other locations, such as the Barrick and Newmont Mining Corporation’s jointly operated Super Pit in Kalgoorlie, Australia, we have committed to reducing mercury emissions. Mercury sources include the carbon kiln, where controls were installed before the end of 2005, and the Gidji roaster, where studies are still underway to determine how to best implement mercury controls.

Barrick and other industry peers are working with regulators around the world to improve mercury control technology and strengthen regulatory oversight relative to this important issue.

Summary

Barrick is committed to state-of-the-art emissions control equipment at all of its operations. Solutions will come sooner and more dramatically if industries voluntarily curtail emissions, rather than wait for governmental mandates. Along with its strong support for voluntary measures, Barrick also supports the development of regulatory programs based on sound science.

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