The US Environmental Protection Agency (EPA) declared on Thursday that the cost of regulating mercury and other toxic emissions from power plants is not “appropriate and necessary.” This conclusion stems from the EPA’s revised cost-benefit analysis.

The new analysis only includes benefits from regulating hazardous air pollutant emissions; it does not account for benefits from regulating particulate matter. The EPA also acknowledges that the cost-benefit analysis fails to quantify other existing benefits.

Based on the new cost-benefit analysis, the cost of complying with the Mercury and Air Toxics Standards (MATS) reaches between $7.4 to $9.6 billion annually, while the compliance benefits only amount to $4 to $6 per year.

The EPA claims that the MATS rule will remain in effect. However, the Environmental Defense Fund (EDF) claims that the EPA’s Revised Supplemental Finding will result in more mercury, lead, arsenic and acid gas emissions each year.

In 2016 the EPA claimed that the MATS prevented 11,000 premature deaths and thousands of illnesses per year. The new roll back could endanger those lives.