Wyoming’s Republican congressional delegation asked the Interior Department on Monday to exempt states that already regulate hydraulic fracturing, or fracking, from a proposed rule governing the practice on federal land.

Sens. John Barrasso and Mike Enzi, along with Rep. Cynthia Lummis, said they’re concerned the draft rules from the department’s Bureau of Land Management would be duplicative. That, they said, could deter people from drilling for oil and gas on federal lands within their states, costing “hundreds of millions of dollars in revenue.”

“Federal law and regulations often delay investment and job creation for years. Consequently, Federal law and regulations push investment out of public land states and into other states where there is greater regulatory certainty,” the lawmakers wrote to Interior Secretary Sally Jewell.