The rule is sure to face legal challenges

The rule would require deep cuts in emissions of mercury, acid gases and soot from coal-fired power plants and is likely moncler jackets to help reshape the industry as companies turn off old plants and decide whether to clean up existing ones or switch to cleaner-burning fuels such as natural gas. It will cost about $9.6 billion annually to implement but will provide substantially more in health benefits each year, including 100,000 fewer heart and asthma attacks, the Environmental Protection Agency said.

The rule is sure to face legal challenges and Republicans vowed to continue as-yet unsuccessful efforts to delay it with legislation. But Wednesday's announcement was a major victory for public-health advocates who have been fighting for years for the EPA to institute the long-overdue standards. Revisions to the Clean Air Act in 1990 required reductions of mercury and other pollutants. The first power-plant standards set out by President George W. Bush's administration were rejected by a federal court in 2008.

"These standards are 22 years in the making. They have not been a surprise," said EPA Administrator Lisa Jackson. "They are based on technology and science and, we believe, based firmly in the law."

President Barack Obama, in a video posted on the White House's website, said the standards were "common sense" and "cost-effective." "It's a good day in the fight for clean air," said Mr. Obama, whose campaign website already touts the new rule.

The administration held its ground on the air-toxins rule despite objections. Some power companies and electric-grid operators said the rules will go too far, too quickly, and could put the reliability of the grid at risk.

In a nod to the reliability concerns, the Obama administration encouraged the states that will enforce the pollution standards to allow four years "when justified" for companies to install retrofits to comply with the rules, instead of the statutory three. The EPA said the rule would allow additional wiggle room to address local reliability problems if they arise.

Those gestures didn't moncler eric light black jackets for men please the industry, which had wanted a more explicit guarantee that plants needed for reliability could be kept online.

The Edison Electric Institute, which represents power firms, said it was "the most expensive rule in the agency's history."

Chip Yost, vice president for energy and resources policy at the National Association of Manufacturers, called the rule a "train wreck" and said it would burden companies also facing other pending EPA air-quality rules.

EPA projects the rule announced Wednesday will require power plants to cut emissions of mercury, a neurotoxin, by about 75% by 2016 and reduce emissions of hydrogen chloride, an acid gas that irritates the respiratory system, by 88%. Those requirements add to earlier rules calling for plants in some states to cut back on gases that form smog and soot. Other pending rules would require plants to take in less water for cooling and impose new rules for handling of coal waste.

"The EPA is being very, very aggressive in their rule-making. It takes time to engineer these changes. It takes time to switch from coal to gas," said Mr. Yost, who warned of higher costs for manufacturers and consumers.

The EPA said some 60% of the 1,400 affected coal- and oil-fired generating units already complied with the rule. Many power companies, including Exelon Corp. and Calpine Corp., support the rules because they rely less on coal-burning generation.

Others have already retrofitted plants to comply with state regulations. One of those firms— Constellation Energy Group Inc.—spent $885 million over three years to retrofit its Brandon Shores plant in Maryland, said Paul Allen, the company's chief environmental officer. "When you've invested a lot of money and when you're complying with strict rules as we have in Maryland, it doesn't come as a surprise that you believe other companies should shoulder their share," Mr. Allen said.

By contrast, American Electric moncler giacca donna 2011 pop star sub-gloss black Power Co., the nation's largest consumer of coal, has said that complying with a series of EPA regulations could cost the company between $6 billion and $8 billion through 2020. Spokeswoman Melissa McHenry said the EPA made some "improvements" but was still underestimating the cost of putting the rule in place on the agency's timeline.