The Environmental Protection Agency has issued groundbreaking national limits for mercury emissions. The new regulations limit mercury air emissions from cement plants, one of the largest sources of mercury air pollution in the United States.

The rules would cut mercury emissions from the LaFarge Ravena plant by nearly a half.Specifically, the new rules strengthen emissions limits for new cement kilns, place limits on existing kilns, and also set limits to reduce emissions of acid gases. In addition, the action regulates particulate pollution and smog-forming emissions from both new and existing cement kilns.

EPA Administrator Lisa Jackson called the measure a "historic step" toward reducing pollution. Mercury has been linked to a wide range of health problems, particularly brain damage in children.

Existing cement plants have until 2013 to comply with the new regulations.  When fully implemented, EPA approximates that mercury emissions will be reduced by 92 percent annually.  The new regulations are estimated to create public health and environmental benefits of between $6.7 billion and $18 billion, according to the EPA.

The new rules will have a significant impact at the LaFarge cement plant in Ravena, just south of Albany, which is the state's second-largest source of mercury pollution.

The Times Union reports that some environmental groups, such as Community Advocates for Safe Emissions, are disappointed that the new rules won't take effect for another three years. DEC reports that mercury emissions from LaFarge would drop by nearly a half under the new rules.