With a formal complaint filed by the Wyoming Attorney General's office, the state became the first to challenge a new federal rule that regulates hydraulic fracturing on public lands. 

Among other things, the rule requires disclosure of chemicals used in fracking and tests to make sure a well isn't leaking. According to the complaint filed in federal district court today, the new rule represents federal overreach by the Bureau of Land Management and conflicts with Wyoming’s own hydraulic fracturing regulations.  

Shannon Anderson, with the Powder River Basin Resource Council, says Wyoming does already have strong rules on the disclosure of fracking chemicals.

"But nationally there is a need to have consistent and strong regulations to address hydraulic fracturing on federal land," Anderson said.

North Dakota is also considering legal action.