- If we consider just the hazardous air pollutants (HAPs) targeted by EPA’s Mercury Air Toxics Standards (MATS) rule, costs exceed quantifiable benefits by 1,600 times to 2,400 times–a potential PR disaster for the agency.
- To sell the rule to Congress and the public, EPA touted the “co-benefits” of the rule’s coincidental reductions in fine particulate matter (PM2.5) pollution.
- In fact, EPA attributes more than 99 percent of the rule’s monetized health benefits to collateral reductions in PM2.5-related emissions.
- But about 99 percent of those co-benefits occur in areas projected to be in attainment with the National Air Quality Standard (NAAQS) for PM2.5.
- To calculate the MATS rule’s PM2.5-related health benefits, EPA ascribes equal value to PM2.5 reductions in areas below and above the NAAQS.
- That is inconsistent with the basic concept of the NAAQS program, which is to set concentration standards at a level “requisite to protect public health . . . allowing an adequate margin of safety.”
- Once we factor in the lower probability of PM2.5 health effects in areas where exposures are already below the NAAQS, the value of the MATS rule’s co-benefits falls nearly to zero.
- The lion’s share of EPA-estimated Clean Power Plan health benefits also disappears.
- Unless EPA makes its impact assessments consistent with its NAAQS determinations, the agency’s benefit estimates will become increasingly overstated and less credible over time.
MATS Back in the News
EPA’s 2012 Mercury and Air Toxics Standards (MATS) rule, which established maximum achievable control technology (MACT) standards for mercury and other hazardous air pollutant (HAP) emissions from power plants, is again in the news. The Supreme Court on Monday rejected a petition by Michigan and 26 other states to freeze the rule.
Petitioners complained that EPA continued to implement MATS even though the Court last year deemed the rule to be unlawful. The Court held that EPA “strayed well beyond the bounds of reasonable interpretation in concluding that cost is not a factor relevant to the appropriateness of regulating [HAP emissions from] power plants.”
Although EPA did not compare costs and benefits when deciding whether to regulate power plant HAP emissions, it did compare costs and benefits when promoting the rule to Congress and the public. EPA boasted that although MATS would cost utilities $9.6 billion to implement in 2016, it would generate $37 billion to $90 billion in health benefits in the same year (77 FR 9306).
However, EPA attributed more than 99 percent of the quantified benefits to coincidental reductions in fine particulate matter (PM2.5)–a pollutant not directly targeted by the rule and not classified as a HAP in the Clean Air Act. Specifically, EPA’s Regulatory Impact Analysis (p. 5-93) claimed that reductions in PM2.5-related emissions would avert 4,200 to 11,000 premature deaths in 2016–annual “co-benefits” valued by the agency at $36 billion to $89 billion.
A study by economist Anne Smith of NERA Economic Consulting finds that even if we accept the epidemiological literature supporting an association between mortality and PM2.5 at today’s historically-low levels (skepticism is justified), the MATS rule’s co-benefit estimates are flimflam. [click to continue…]