In a letter to the EPA last summer, utilities and regulatory and labor groups said mercury emissions had been reduced by almost 90 percent over the past decade.
Environmental advocacy groups criticized the move, while the National Mining Association praised it.
The Environmental Protection Agency announced Friday that it was proposing new rules regarding the regulation of hazardous air pollutants, potentially making way for fewer restrictions on various pollutants in the future.
The agency said that the Trump administration was "providing regulatory certainty" by more accurately estimating the costs...
"Once again, the Trump administration is acting in a way that will adversely affect the health and safety of those living from coast to coast". The Obama administration estimated that the measure would prevent as many as 11,000 premature deaths from asthma, other respiratory diseases or heart attacks.
The 2011 Obama administration rule led to what electric utilities say was an $18 billion clean-up of mercury and other toxins from the smokestacks of coal-fired power plants. Although the EPA's proposal does not eliminate the regulations outright, it sets the stage for weakening them altogether, particularly, as The New York Times observes, in weakening "the ability of the E.P.A.to impose new regulations in the future by adjusting the way the agency measures the benefits of curbing pollutants, giving less weight to the potential health gains".
"What has changed now is the administration's attitude towards public health", said Clean Air Task Force Legal Director Ann Weeks in a statement. "The misguided proposed changes leave MATS legally vulnerable and foolishly make it harder to strengthen mercury pollution reduction standards in the future to better protect children's and women's health, and Great Lakes fisheries".
Representatives of the Environmental Protection Agency (EPA) in the U.S. have proposed going back on a previous endorsement of limits on mercury pollution.
Janet McCabe, a former air-quality official in the Obama administration's EPA, called the proposal part of "the quiet dismantling of the regulatory framework" for the federal government's environmental protections. The federal Energy Information Administration says US coal consumption in 2018 is expected to be at its lowest level in almost four decades. Coal power plants in this country are the largest single manmade source of mercury pollutants, which enters the food chain through fish and other items that people consume. Even as coal use rises in China and India, the domestic industry has struggled to compete with cheaper electricity produced from natural gas and renewable energy.
The proposal will be up for 60 days of public comment before a final ruling goes into effect.