CHEYENNE -- Questions about how to regulate underground storage of captured carbon emissions in Wyoming are proving tricky.

A legislative panel Tuesday delayed action on two carbon sequestration bills because of lingering questions about the complicated legislation.

Gov. Dave Freudenthal and other policy makers are pushing to make the state a leader in carbon capture and sequestration technology and policy. Underground disposal of carbon dioxide gas, believed to be a contributor to global warming, is seen as critical to the continued success of the state's coal economy.

“What we're trying to do is get ahead of the game,” said Sen. Tony Ross, R-Cheyenne, a co-chairman of the Legislature's Joint Interim Judiciary Committee, which is crafting the bills for the upcoming budget session.

The bills cover two areas: who owns underground carbon dioxide storage areas, also called “pore areas,” and which agencies should be in charge of regulating carbon sequestration. The ownership issue is the most important.

At question is whether the pore spaces belong to surface holders or mineral owners. Wyoming split-estate laws provide separate ownership for each.

The legislation in its current form would grant ownership to surface holders. That's largely because court decisions across the nation hold that pore space created by the extraction of oil and gas belongs to the surface owner.

Spokesmen for the Wyoming Farm Bureau Federation and the Wyoming Stock Growers Association spoke out in support of the ownership bill.

Wyoming Mining Association spokesman Marion Loomis asked the committee to differentiate between pore spaces used for carbon sequestration and other purposes, such as the storage of other materials. The committee declined to act on Loomis' recommendation.

Two agencies, the Wyoming Oil and Gas Conservation Commission and the state Department of Environmental Quality, have expressed interest in regulating carbon sequestration. After much deliberation, the committee opted to withhold a decision.

The committee is carefully crafting the bills so they don't infringe on the state's long-standing extraction traditions.

“Our point here is to help clarify the law without destroying 100 years of oil and gas production,” Rep. Mary Throne, D-Cheyenne, said.

But lawmakers say carbon sequestration technology and regulations are urgently needed. Without them, Wyoming coal may become less viable as the political tide turns against coal-fired power plants and other carbon gas emitters, officials said.

“This is about jobs,” Rep. Tom Lubnau, R-Gillette, said.

Geological formations such as the Rock Springs Uplift have been offered as locations where millions of tons of gas could be injected and stored long term.

Mark Northam, director of the University of Wyoming School of Energy Resources, told the committee that Wyoming is positioned to be a leader in carbon sequestration.

“We have an opportunity in Wyoming to set precedents if we do this correctly,” said Northam, who painted a picture of carbon sequestration as a complex and somewhat uncharted field of geological science.

He said the major environmental concerns are interactions with fluids and other subsurface minerals and potential groundwater contamination. He said the risk of accidental discharge is minimal.

He explained that injections of carbon dioxide will displace ancient reservoirs that will then be in flux for centuries.

Once underground, the gas can spread upward and outward in massive plumes that will require long-term monitoring to make sure it stays in place, Northam said.

He said it can take hundreds of years for the gas to find its permanent resting place beneath the earth's surface, and regulations should be crafted accordingly.

“This is a much longer-term issue than we are used to dealing with in the oil and gas field,” Northam said.

The Joint Interim Judiciary Committee will take up both bills when it meets again in January.

Support of two-thirds of the House or Senate will be needed to introduce the bill during the upcoming budget session.

Reach capital bureau reporter Jared Miller at (307) 632-1244 or at jared.miller@trib.com.