Shell Oil won approval of two air pollution permits for oil exploration using a drillship and fleet of support vessels off the North Slope of Alaska. The 9th U.S. Circuit Court of Appeals upheld two permits to emit pollutants as part of the exploration for oil and gas in the Chukchi and Beaufort Seas in an opinion Wednesday.
A host of environmental groups challenged the permits for alleged failure to satisfy the Clean Air Act requirements.
“We conclude that the EPA’s grant of an ambient air exemption to Shell conditioned on an effective safety zone excluding the public is a permissible interpretation of its ambient air regulation,” said Judge Margaret McKeown.
The permits allow the drillship and its associated fleet to conduct drilling activities between July 1 and November 30 each year. Under terms of the permits, the company must use specific technologies to limit emissions of specific pollutants and comply with other requirements.
The EPA exemption from air pollution requirements covers an area for ambient air within a 500-meter radius of the drillship.
The appeals court held that because the Clean Air Act is ambiguous as to the applicability of best available control technology, BACT, to support vessels not attached to an outer continental shelf source. The court found the EPA’s interpretation of the law was reasonable.
“We defer to the EPA’s reasonable construction of the statute,” wrote McKeown. The BACT does not apply to mobile support vessels unattached to the drillship,” she said.
Judges Michael Daly Hawkins and Carlos Bea joined the opinion.
Case: Redoil v. EPA, No. 12-70518