Bloomberg Law
March 23, 2022, 8:00 AM

Mercury from Power Plants: EPA Must Get the Standards Right

Ellen Kurlansky
Ellen Kurlansky
Environmental Protection Network

In a move to right a Trump-era wrong, the Environmental Protection Agency recently proposed to restore the finding that it is “appropriate and necessary” to use the Mercury and Air Toxic Standards (MATS) to regulate mercury emissions and other hazardous air pollutants from coal and oil-fired power plants.

Mercury is a powerful neurotoxin that harms fetuses and children, and increases the risk of heart attacks and cardiac disease in adults. The EPA considers mercury the “hazardous air pollutant of greatest concern” from these plants.

Since MATS was issued in 2012, emissions of mercury and other hazardous air pollutants have been reduced by a hefty 86%, improving public health. The electric power industry is largely in compliance with the regulation and has used available and affordable technology to provide the public with reliable and affordable electricity.

Yet, this is the fourth time that the EPA has been forced to decide that regulating these emissions is appropriate and necessary. And MATS has been demonstrated to be both appropriate and necessary. So, what’s going on?

The Cost-Benefit Analysis When Regulation Was Issued

When the EPA issued the original regulation, it conducted a required cost-benefit analysis that claimed that the costs of the regulation were high—over $9.6 billion in 2015, the year facilities would need to comply with the standards. The benefits, however, were much higher—about $90 billion each year.

Almost all the benefits that the EPA counted were from the reduction of other harmful pollutants, called “co-benefits,” not the result of reductions of mercury or other hazardous air pollutants. In fact, the agency counted only a small fraction of the benefits related to the reduction of mercury emissions.

As a result, MATS has been vulnerable to numerous legal challenges claiming that the EPA has not made the case for the regulation. The Trump administration was wrongly able to use this analysis to claim that the regulation was not appropriate and necessary.

Proposed New Finding Corrects Problems in Earlier Analysis

The proposed new finding corrects many of the problems with the old analysis. The EPA should be commended for acknowledging that its original calculation of the costs was significantly overestimated. As often happens, the regulated industry found a way to meet the standards at a much lower cost by using fewer and less expensive controls.

On the benefits side, the EPA has corrected a grave error made when the it was led by former coal-industry lobbyist Andrew Wheeler. In 2020, the agency refused to acknowledge the co-benefits of reductions in auxiliary pollution that resulted from the rule, because they weren’t the targeted pollutants. Accounting for all the benefits (and disbenefits) of a regulation is not only sound economic practice; it’s good government.

The new proposal better presents the benefits of reducing mercury. This time, the EPA considered the impacts on the general population rather than the very narrow segment of the population that the EPA considered before.

The agency also looked at some cardiovascular benefits of reducing mercury exposure. As a result, the calculated value of the direct benefits in the proposal is greater than previously considered. However, it is still not fully consistent with the current available science and, as a result, still undercounts the benefits of reducing mercury pollution.

There are, for example, well-established modeling tools available that do a good job of predicting the transport of mercury. They are consistent with what we have been able to measure in real life, including an update to the EPA’s own model.

Better Analysis of Health Impacts Is Still Needed

The version of the transport model that the EPA used for the previous regulatory impact analysis and continues to rely on, however, is based on an out-of-date understanding of mercury transport. It leads to an underestimation of exposures in the U.S. The EPA should make a more accurate assessment of actual exposures based on one of the more reliable modeling platforms.

In looking at the neurotoxic effects of mercury, the EPA only looked at the loss of IQ points in children exposed before birth. There are several additional well-documented impacts such as delayed learning, behavioral impacts, memory effects, and others that could be measured in children at all stages of development and analyzed.

We also urge the EPA to consider the relationship between exposure to methylmercury, a very toxic form of mercury that is formed when bacteria react with mercury in water, and its effects on the cardiovascular system.

The EPA has not done an analysis that would allow a more accurate estimate of cardiovascular effects—including heart attacks and cardiac disease caused by mercury from power plants. Instead, EPA’s short-hand analysis undercounts these serious health impacts.

The EPA is right: It is appropriate and necessary to regulate hazardous emissions from coal-fired and oil-fired power plants, and it should be applauded for this proposal. But by continuing to underestimate the benefits of reducing mercury emissions, the agency is once again giving fodder to those who want to jettison the regulation and discredit the EPA.

A better analysis of the benefits would make it clear that the EPA, by controlling pollution from the industry with the highest hazardous emissions in the U.S., is taking action that is not only appropriate and necessary, but also critical to protecting public health.

This article does not necessarily reflect the opinion of The Bureau of National Affairs, Inc., the publisher of Bloomberg Law and Bloomberg Tax, or its owners.

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Ellen Kurlansky is a member of the Environmental Protection Network where she volunteers her time to support sound environmental policy and provide high level analyses and recommendations for proposed EPA rulemakings. She was an economic and policy analyst at the EPA for 30 years, where her work focused on control of air pollution from the electric power industry.