Largest Open Pit Mine in North America Cause for Investor Concerns - Investors Representing $170 Billion Urge EPA to Safeguard Alaska's Bristol Bay

Trillium and Calvert-Led Investor Coalition Asks EPA for Clean Water Act (CWA) Review for Pebble Copper and Gold Mine, Sited for the Headwaters of the Bristol Bay Fishery Reserve

BOSTON, April 12, 2011 /PRNewswire-USNewswire/ -- Nearly 30 investor organizations representing over $170 billion in assets are urging the U.S. Environmental Protection Agency (EPA) to initiate a review process under the Clean Water Act to evaluate the mine waste impacts of the proposed Pebble Mine on Alaska's Bristol Bay watershed, which produces roughly half of the world's commercial supply of wild sockeye salmon.

Led by Trillium Asset Management Corp. (Trillium) and Calvert Investments (Calvert), the organizations hold over 13 million shares in Anglo American plc, the UK-based mining company behind the proposed mine.

"This proposed mine has potentially devastating consequences for the people and the ecosystem of Bristol Bay," said Jonas Kron, vice president at Trillium. "The potential impact of this project and the national importance of Bristol Bay means review under Section 404(c) of the Clean Water Act is warranted."

"Ecosystem degradation is of serious concern to investors," said Stu Dalheim, director of shareholder advocacy at Calvert. "A recent United Nations report showed environmental costs from global human activity equate to an estimated US$ 6.6 trillion - approximately 11 percent of global GDP in 2008. Responsible resource development is critical to all economic, environmental and cultural stakeholders."

The Bristol Bay region of Alaska is the site of the largest remaining runs of wild sockeye salmon and is the home of Alaska Native people who continue the subsistence fishing and hunting traditions of their ancestors. Bristol Bay is an important economic driver for the commercial fishing, sport hunting and sport fishing industries of North America, generating $450 million in annual revenue and providing some 10,000 jobs.

Pebble Mine is a copper, gold and molybdenum mine proposed at the headwaters of the Bristol Bay Fishery Reserve by U.K.-based Anglo-American and Northern Dynasty Minerals Ltd of Canada. The combined impact and risks associated with a proposed mine in this region are unprecedented. Under current plans, the project would involve the largest open pit mine in North America, enormous toxic tailing ponds and a significant infrastructure footprint in critically important habitat. A peer reviewed 2010 risk assessment by The Nature Conservancy studied the impacts of such large-scale mining in the Bristol Bay region, and concluded that the risks to wild salmon populations are "very high," and that it is cause for significant concern regarding the long-term abundance and sustainability of salmon in the region.

This investor statement comes on the heels of the EPA's announcement in February in response to petitions by Bristol Bay native tribes and corporations, commercial fishermen, businesses, and others that the Agency would conduct a scientific assessment of the Bristol Bay watershed to evaluate the suitability of large-scale development in the region. Many observers see the assessment as a precursor to a full EPA 404(c) review.

Section 404(c) authorizes EPA to "prohibit, restrict, or deny the discharge of dredged or fill material at defined sites in waters of the United States (including wetlands) whenever it determines, after notice and opportunity for public hearing, that use of such sites for disposal would have an unacceptable adverse impact on one or more of various resources, including fisheries, wildlife, municipal water supplies, or recreational areas."

ABOUT TRILLIUM AND CALVERT

Trillium Asset Management Corporation is the oldest and largest independent advisor devoted exclusively to sustainable and responsible investing.

Calvert Investments has been a leader in the field of sustainable and responsible investing (SRI) for over 25 years, demonstrating that investors may manage risk and enhance long-term portfolio performance by investing in well-governed, sustainable and responsible companies.

SOURCE Trillium Asset Management Corp. and Calvert Investments