U.S. limits for sulfur-dioxide emissions from power plants, factories and industrial sources were upheld by a federal appeals court, which rejected a lawsuit brought by North Dakota and Texas.
A three judge panel of the U.S. Appeals Court in Washington said today that the Environmental Protection Agency didn’t act “arbitrarily” in setting the 2010 rule that restricts sulfur-dioxide levels in the air to 75 parts per billion over a one-hour period.
“EPA cites evidence that current levels of SO2 in the ambient air, even when the air quality meets the current SO2” standards, “still cause respiratory effects in some areas,” U.S. Circuit Judge David Sentelle wrote in the opinion.
The regulation revokes standards for the pollutant adopted in 1971 that included limits of 140 parts per billion measured over 24 hours. North Dakota and Texas were among five states that sued over the rule.
The EPA cited research that shows short-term exposure to sulfur pollution poses a greater health threat than past rules took into account, including risks to children, the elderly and people with asthma. Power plants account for almost 70 percent of sulfur dioxide in the air, according to the EPA.
On July 13, a different appeals court panel in Washington upheld EPA’s standards for nitrogen dioxide.
The case is National Environmental Development Association’s Clean Air Project v. Environmental Protection Agency, 10-1252, U.S. Court of Appeals for the District of Columbia (Washington).