The Environmental Protection Agency’s independent appeals board has upheld final air pollution permits that oil giant Royal Dutch Shell needs to launch a controversial drilling project in Arctic waters off Alaska’s coast this summer.

The Environmental Appeals Board on Friday rejected environmentalists’ challenge to permits EPA issued for Shell to operate the Kulluk drilling unit.

“Achieving a usable air permit for the Kulluk means Shell has, for the first time, all of the air permits needed to work in the Alaska offshore,” a Shell spokeswoman said.

he step comes 10 weeks after the appeals board similarly denied green group challenges to permits for operating the Noble Discoverer drillship.

A number of parties including the Alaska Wilderness League, the Inupiat Community of the Arctic Slope, the Center for Biological Diversity, and The Wilderness Society had challenged the permits for the Kulluk and Noble Discoverer.

Shell has recently cleared several hurdles in its quest to drill in the Beaufort and Chukchi Seas off Alaska’s northern coast.