The EPA, Mercury, and Air Toxics, Oh My!

December 30, 2018 | 7:48 pm
Photo: John Westrock/CC BY-NC (Flickr)
Kathleen Rest
Former Executive Director

UPDATE (April 15, 2019): You have until the end of the day on Wednesday, April 17, to submit a public comment on this proposed rollback. The Union of Concerned Scientists has made it easy for you to share your thoughts directly with the EPA. For all the details and background, we also wrote a technical guide to help inform discussion; learn more about it here.

The government may be in the midst of a nonsensical shutdown, but that didn’t stop the Environmental Protection Agency (EPA) last week from proposing a new formula of calculating the human health benefits of reducing mercury emissions from power plants (or in their words proposing a “revised Supplemental Cost Finding”).

New and revised for sure, but definitely not in a good way.

In keeping with the Trump Administration’s assault on science and on environmental and public health safeguards (see here and here), the EPA has decided that its own rule adopted during the Obama administration is just too costly and can no longer be justified as “appropriate and necessary.” Too costly for whom, you might ask. Bet you know the answer to that question.

Whose math is funny?

In 2012, the EPA estimated that its Mercury and Air Toxics Standard (MATS) rule would prevent 11,000 premature deaths and over 100,000 asthma and heart attacks each year, as a result of the co-benefits of the reduction in particulate matter pollution that occurs when plants reduce their mercury emissions. The agency estimated the health benefits of reductions in all air pollutants associated with MATS would range from $37 billion to $90 billion, with compliance costs to industry estimated at $7.4 to $9.6 billion annually.

Bah, humbug says EPA Acting Administrator Wheeler. The health benefits of cutting mercury emissions are only $4 million to $6 million max; it’s just not right to count those other co-benefits. Apparently, even the benefits of protecting pregnant women and the brains of their developing fetuses and young children from mercury exposure (a toxin can lower IQ, cause motor function problems, and other nervous system impairments) are too small to worry about, as they are far outweighed by what it could cost power plants to install the required pollution controls.

Never mind that scientists have concluded that the EPA’s 2011 regulatory impact assessment greatly underestimated the monetized benefits of reducing mercury emissions from power plants. And never mind that most coal plants have already come into compliance with MATS by installing the necessary pollution control technology. Oh, and almost forgot to mention that electric companies have reduced mercury emissions by 90% since the MATS rule took effect in 2012 (see quote by Brian Reil, a spokesman for the utility trade group Edison Electric Institute in this article.)

So, what is an agency bent on rolling back regulations to do? Well, why not narrow the scope of what can count as benefits and do a new cost-benefit analysis. Done! And presto, the EPA now asserts it is no longer “appropriate and necessary” to regulate hazardous air pollution emitted from power plants under the Clean Air Act. The EPA is also asserting that there are no new technologies or methods of operation for controlling any residual risks of mercury and other hazardous air toxics that would justify the costs of further reductions. [So much for the agency’s confidence in innovation.]

An end-of-year gift (to industry) that will keep on giving

I suppose one can give a nod to the EPA’s impeccable timing in announcing this roll-back—at the end of a week between the holidays and while the government was shut down. Or perhaps the agency thought the public wouldn’t grasp the seriousness of its crafty ploy that leaves the actual rule intact (for now) while sideswiping its analytical underpinning.

But we and the broader public health and environmental communities are not fooled (some early reflections here and here and a more detailed analysis here). This maneuver to change the calculus of benefits sets a dangerous and far-reaching precedent—one that will make it ever more challenging to set protective regulations in the future. And one that clearly sets the stage for rescinding MATS itself, which BTW was included in Murray Energy CEO Bob Murray’s wish list of environmental rollbacks submitted to the Trump administration in early 2017. [Murray was an important client of Acting Administrator Wheeler in his former life as a coal industry lobbyist. See here and here.]


We can expect to see a notice published in the Federal Register (FR) shortly, which will open a 60-day public comment period. [See the submitted notice here, which includes mention of at least one public hearing on the proposal—location, date, and time to be published in a second FR document.]

It’s critical that we let the EPA know what we think of its wonky little revision. It’s not little; it’s a crafty, nasty, and dangerous proposal that could rollback current safeguards and undermine future public health and environmental protections. Get ready to comment and alert your colleagues to do the same. We will watch for the FR notice and let you know when it appears.