Opinion: Supreme Court Ruling on EPA's Mercury Rule Will Have Little Effect

The June 29 ruling "is probably not going to change the mercury regulations," writes Roberts, formerly with Grist. "It's probably not going to have any effect on the power sector. It probably won't establish any significant legal precedents. The most likely outcome of the ruling is ... nothing much."

Michigan v. Environmental Protection Agency centered on costs, specifically when the cost-benefit analysis should be calculated. "Industry groups and states like Michigan sued the EPA, arguing that the agency should have taken costs into account during that initial stage — when determining whether mercury regulations were 'necessary and appropriate' in the first place," writes Brad Plumer in a separate Vox piece on the ruling. "If the agency had done so, they argued, it would have realized that its initial determination was not "appropriate" since the costs vastly outweighed the tiny benefits."

EPA did do the analysis, but after it crafted its regulations—and that was the basis of the suit and why the Supreme Court ruled as it did, which brings us to Roberts' interpretation of it: "It is likely pointless," he writes at the start of his opinion piece. And he's not alone in making that assessment.

Back in May, SNL Financial determined that the ruling "will be (mostly) moot," largely because only "22 plants, representing less than 1% of U.S. power capacity and 1% of U.S. energy production in 2013" lack the mercury controls." However, Eric Wolff went on to write that it "will have legal ramifications for future EPA rules."

According to Roberts, that won't happen, though it could have.

• "The ruling only applies to the specific subsection of the (Clean Air Act) devoted to [hazardous air pollutants, also called air toxics] from power plants. It won't affect how future EPA regulations are developed."
• He cites Chevron vs. NRDC that wasn't used in the ruling—had it, it could have reigned in EPA's authority.
• It didn't take up the issue of "co-benefits or ancillary benefits. Plumer explains that when the EPA analyzed the mercury rule after it had been established, "it calculated that the benefits of reducing mercury from power plants were just $4 million to $9 million." Only when EPA estimated "co-benefits" were the enormous health cost savings revealed.

The agency pointed out that if coal-fired power plants installed scrubbers to clean up mercury, that would also reduce other pollutants, particularly fine particulates like soot. And these pollutants are widely known to damage lungs and kill people. The EPA estimated that these "co-benefits" were worth some $26 billion to $89 billion per year. Looked at in this light, the benefits of the mercury rule far exceeded the cost.

The main deleterious effect of the ruling is that 22 dirty coal plants will not be required to install scrubbers. "That's not nothing — especially to the vulnerable populations exposed to those toxic pollutants," writes Roberts.

Now what?

Contrary to some media reports, the mercury rule is not "struck down" but remanded to the DC Circuit Court which will "decide how to proceed," adds Roberts.

Hat tip to Darrell Clark.