BISMARCK, N.D. (AP) -- The North Dakota Supreme Court has heard the first of two legal challenges to an oil refinery planned near Theodore Roosevelt National Park.

Tuesday's arguments involve a lawsuit brought by the National Parks Conservation Association. It's concerned about how the state will regulate emissions from the Davis Refinery under a permit issued last year by health officials. The association says the permit lacks safeguards that would protect the park and its visitors from air pollution.

The Bismarck Tribune reports the state maintains that the permit it issued does adequately control emissions, in part by requiring a leak detection system.

A second legal challenge to the refinery will be heard before the Supreme Court next week. A pair of environmental groups are suing over issues surrounding the site of the refinery.