NEW ORLEANS - Texas and Louisiana will have to come up with better plans for handling ozone, a federal appeals court has ruled.
The U.S. Court of Appeals for the Fifth Circuit on March 25 found no fault in the Environmental Protection Agency rejecting the strategies of the two states for preventing ground-level ozone caused when sunlight interacts with pollutants.
The case involves the EPA's 2015 reduction of the maximum allowable amount of ozone and part of the Clean Air Act that considers whether pollution will spread from state to state via wind.
Texas, Louisiana and Mississippi were among 20 states challenging the EPA's denials of their state implementation plans (SIPs) of the new ozone standards. They argued the EPA shouldn't independently review SIP submissions for compliance with the CAA's Good Neighbor Provisions.
"We disagree," Judge Priscilla Richman wrote. "States retain complete discretion over the 'means to achieve' the air-quality ends set by EPA.
"EPA cannot disapprove a SIP because it believes it unwise or misguided... (T)he sole question for EPA is whether a SIP submission 'meets all of the applicable requirements of' the CAA."
That includes the Good Neighbor Provision, included in the CAA to address pollution traveling state lines on the wind. The case is one of many in which Texas Attorney General Ken Paxton has taken the EPA to court to challenge its findings.
Paxton sued in 2023, drawing criticism from groups like the Sierra Club, which claimed Texas wanted to continue "dumping its trash in other states' backyards."
The EPA rejected the Texas SIP because it failed to impose emissions limitations even though Texas' own interpretation showed they traveled significantly downwind. Texas said its air does not significantly affect the ozone concentrations in California and Colorado.
The EPA noted that its technique for evaluating a state's projected contribution focuses on the five-to-10 days with the highest projected ozone levels. The State, however, used all days projected to be above the 70 ppb level, which reduced the average, the EPA said.
"(T)he monitored ozone design value trends provide evidence that future year modeled ozone levels are underestimated by [Texas'] modeling and there are likely more receptors that should have been identified with additional potential linkages," the EPA wrote.
The Fifth Circuit upheld denial of Texas' and Louisiana's SIPs, but reversed Mississippi's.
"We cannot say that EPA's approach to critiquing Texas' modeling evinced that it failed to 'reasonably consider the relevant issues and reasonably explain the decision," Richman wrote.