SAN FRANCISCO (CN) - The Ninth Circuit upheld stricter emission limits for an Arizona power plant, as well as other measures to manage regional haze.
Federal regulators tightened the rules after disapproving a state implementation plan Arizona had proposed in 2011 for managing three of its fossil-fuel power plants over the long term.
Though Arizona had proposed a nitrogen-oxide limit of 0.32 lb/mmBtu for both units of the Coronado Generating Station, the Environmental Protection said the coal-fired power plant in eastern Arizona needed a much lower limit: 0.050 lb/mmBtu for Coronado Unit 1, and 0.080 lb/mmBtu for Coronado Unit 2.
Though Arizona challenged the EPA's actions were arbitrary and capricious under the Administrative Procedure Act, a three-judge panel of the Ninth Circuit threw out the appeal Wednesday.
The court saw nothing wrong with the EPA's decision to uphold other aspects of Arizona's plan, saying the law "expressly permits" such partial approval.
Furthermore, the EPA's conclusions concerning were "well explicated, carefully grounded in the administrative record and analytically reasonable," the 49-page opinion states.
The agency's disapproval of Arizona's cost analysis for its Coronado power plant was also neither arbitrary nor capricious because the state relied on insufficiently detailed cost data, according to the ruling
Plus, the EPA "rationally determined that Arizona's BART visibility analysis for Coronado was unsupported by explanation and inconsistent with the Clean Air Act and its regulations," Judge Marsha Berzon wrote for the panel.
The agency also "reasonably concluded that Arizona's cost and visibility impact analyses for Coronado suffered from significant analytical defects," Berzon added.
Though the court also upheld the EPA's visibility improvement assessment and its new cost analysis, it declined to rule on the reasonableness of the agency's new emissions limits, "as they are likely to be altered."
Attorneys for the state and EPA have not returned emails requesting comment.
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