The EPA’s analysis of the new mercury rule (the Utility Maximum Achievable Control Technology, or Utility MACT) is yet another example of regulatory bait-and-switch. The rule refers to mercury but really targets CO2, and it generates its purported benefits from reducing particulates that are already covered by other regulations. For an excellent and revealing analysis of the EPA calculations, see Anne E. Smith’s technical comments.

The EPA claims this rule would produce $53 billion to $140 billion in annual benefits, but at most $6 million of the benefits come from mercury reductions. We can compare this $6 million to the EPA’s estimated costs of more than $10 billion per year. However, even this bad deal is likely overly optimistic.

First, other independent annual cost estimates range from $70 billion to $200 billion—well above the EPA estimate.

Second, the benefits of particulate reduction and mercury reduction are based on questionable assumptions.

Suppose a study examined accidents in which four people each fell a distance of 50 feet. If two of the four died, the prediction of what is called a linear-dose response is that for every 200 feet that a population falls, two people will die. This would be averaged out among the population and the distance of falling. For instance, this linear-dose response would predict that for every 400 people who step off a six-inch curb, two will die from the impact. A cost-benefit calculation using this assumption would show that even a small city would save thousands of lives per day by cutting down all curbs. Though stepping out into street may be dangerous for other reasons, dropping down six inches is not the cause of any fatalities. Nor would eliminating curbs reduce any of the other dangers of stepping into the street.

Likewise, the EPA’s analysis of the Utility MACT rule using a linear-dose response is way off base, because existing mercury and particulate levels are more analogous to stepping off a six-inch curb than a 50-foot cliff.

In summary:

• The benefits of MACT’s mercury reduction are negligible.

• Particulates are already controlled by other regulations under the Clean Air Act, and the benefits calculated by the EPA for this rule are almost certainly exaggerated as well.

• The EPA’s cost estimate for the rule is far below independent estimates.

The proponents of the proposed rule tell stories of mercury poisoning and point to benefit estimates as though they reflect a reduced incidence of mercury poisoning. However, even the EPA’s own cost-benefit calculations reveal that this is not a mercury rule in any meaningful sense—less than one-tenth of one percent of the estimated benefits come from mercury abatement. Those who conflate the exaggerated benefits of particulate reduction with the virtually nonexistent benefits of controlling mercury emissions perpetrate a costly fraud.