U.S. EPA this week finalized new air pollution control requirements for seven iron ore processing facilities in Minnesota and Michigan.

At issue are taconite facilities owned by companies including U.S. Steel Corp. and ArcelorMittal S.A.. Taconite is a type of iron deposit that helps fuel the economies in the region around Lake Superior.

EPA's rule, which has caused some controversy within the industry and among lawmakers on Capitol Hill, promises to reduce nitrogen oxide emissions by about 22,000 tons per year and sulfur dioxide emissions by about 2,000 tons per year. Plants must also install continuous emissions monitors.

"This is a terrific first step at regulating an industry that for too long has been allowed to escape pollution controls, thus negatively impacting treasured places like Voyageurs and Isle Royale national parks and the Boundary Waters Canoe Area Wilderness," said Christine Goepfert, a regional program manager for the National Parks Conservation Association.

"These wild places attract hundreds of thousands of visitors each year, helping spur the nearly $22 billion that tourism contributes to local economies," Goepfert added.

Former Minnesota Republican Rep. Chip Cravaack pushed for legislation to roll back EPA's ability to promulgate the so-called regional haze regulations, meant to improve visibility at national parks and wilderness areas. He wanted the agency to approve his state's best available retrofit technology (BART) plan rather than craft its own (Greenwire, Oct. 10, 2012).

EPA said it made changes to the final rule, including compliance deadlines, based on feedback from taconite companies. The agency reported more than 1,000 comments and hosted a public hearing because of the high interest in the issue.

Democratic Rep. Rick Nolan, who unseated Cravaack to represent northeastern Minnesota but promised to continue supporting the taconite industry, is taking a measured approach. A spokesman said Nolan is studying the rule and discussing it with industry leaders.

Navajo Generating Station

EPA's regional haze guidelines have caused unease among critics for tightening controls at power plants around the country. Proposals concerning the Navajo Generating Station near the Grand Canyon in Arizona have been among the more controversial.

As with taconite, House lawmakers passed legislation limiting EPA oversight of regional haze issues and included a rider to protect the Navajo plant.

Now EPA is proposing a compromise for reducing emissions at what it calls one of the nation's top nitrogen oxide polluters. It would give the plant until 2023 to install new controls under an "alternative BART" scenario.

EPA said the proposal, which would reduce emissions by 84 percent or more than 28,000 tons per year, would give credit to the plant for installing low NOx burners.

"This alternative also recognizes the importance of NGS to numerous Indian tribes located in Arizona and the federal government's reliance on NGS to meet the requirements of water settlements with several Indian tribes," the agency said.

Earlier this month the heads of EPA, the Interior Department and the Department of Energy released a joint statement promising closer cooperation to reduce pollution from the Navajo Generating Station while also protecting economic development.

Local leaders are worried that the plant's closure would jeopardize jobs, many of them filled by American Indians, and the nearby Kayenta coal mine. The Bureau of Reclamation owns the Navajo Generating Station along with the Salt River Project and various utilities.

Andy Bessler, an organizer with the Sierra Club's Beyond Coal campaign, said, "We applaud the Environmental Protection Agency for requiring the long-overdue cleanup of pollution from this dirty coal plant, which for decades has harmed human health and marred one of the nation's iconic national parks, the Grand Canyon."

The new proposal is subject to public comment and hearings in the coming months.