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The U.S. Environmental Protection Agency (EPA) has been criticized after disclosing that it had spent $2.4 million on reviewing the proposed open-pit copper and gold Pebble Mine in southwest Alaska.

This figure was published as part of the agency's draft watershed assessment released for public comment last year and represents only the amount of money spent on external projects, with internal agency costs not factored in.

One of the reasons for the criticism over the EPA's assessment is the fact that plans for Pebble Mine could be blocked even before the start of the permit process. The issue was debated at a Senate hearing earlier this week, as Republicans attacked Ken Kopocis, a nominee for assistant administrator to the EPA's water office, over the expenses. Kopocis was nominated for the post by President Obama and the senate had to discuss his appointment.

The EPA has the right to ban mining operations under the Clean Water Act if there is evidence that they are likely to cause adverse effects on the environment. The review of the Pebble Mine plans examined the potential impact on salmon ecosystems in Bristol Bay and concluded that the mine would significantly impact fish populations in waterways near to the site where mining operations are to take place.

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A Louisiana Republican senator stated that the EPA's assessment was "completely unnecessary", because the companies that are expected to share the rights over the mine — Northern Dynasty Minerals, Anglo American and Rio Tinto — have not formally announced any plans for the mine, nor have they applied for a Clean Water Act permit. The partnership explained that it was still reviewing various design options and would apply for a permit later, but critics believe this has taken too long. According to a letter sent to the partnership by Rep. Sen. Lisa Mukrowski, the process was started almost 10 years ago. Mukrowski, who claims to be an EPA critic, argued that this delay had "created a vacuum that the EPA has now filled with… three hypothetical mine scenarios."

If plans for the Pebble Mine are eventually approved, it will be the biggest open-pit copper and gold mine in the world. It is predicted that annual operating costs will reach about $1 billion and the partnership estimates it could bring up to $180 million in annual taxes and royalties to Alaska.

Meanwhile, the Daily Caller noted that this is not the first time the EPA has come under fire over expenses for project assessments. Earlier this year, the Daily Caller News Foundation reported that the federal agency had spent $169,381 on sending a group of 16 officials, or $10,586 per person, to carry out a peer review meeting on the watershed assessment. By contrast, the cost per person of the General Services Administration Las Vegas trip came in at $2,740 per person, highlighting the disproportionate expenses of the EPA, the news source pointed out.