As Republican lawmakers consider how closely to align with the climate skepticism and fossil fuel fervor radiating from the White House, a nascent clean air initiative that energy firms want scrapped is fast testing their comfort zone.
Weighing on them is 41 billion cubic feet of methane, a greenhouse gas leaking from many of the nearly 100,000 oil and gas wells on federally owned land. Methane is among the most potent accelerators of global warming, 25 times more harmful than carbon dioxide.
Since the House swiftly voted last month to lift a requirement that escaping gas be trapped and converted to electricity, the backlash has been intense.
Anger is most pronounced in the West, where tens of thousands of residents near drilling operations risk exposure to the toxic compounds that leak in tandem with the methane. Local governments are also desperate for the royalty money they would be entitled to if that gas were turned to energy.
"The thought of a bunch of disconnected lawmakers who don't live next to leaking gas wells deciding to vote to take this protection away from us just leaves me speechless," said New Mexico cattleman Don Schreiber, whose Devil's Spring Ranch in Rio Arriba County is surrounded by 122 natural gas wells.
Supervisors in adjacent La Plata County, Colo., passed a resolution calling on Congress to abandon the rollback. More than 80% of the people in Western states including Arizona, Colorado, Montana, Utah and Wyoming support the Obama-era mandate, according to a Colorado College poll taken in December.
The political tension has left many Republican senators wavering, as they struggle with the potential fallout of going after a signature Obama administration climate change policy that — like many others — has a constituency that extends far beyond climate hawks.
They face competing pressure from the Trump administration, as Environmental Protection Agency Administrator Scott Pruitt rebukes climate science and steps away from his own agency's far-reaching methane blueprint, intended to stem leaks that in some cases are so large they can be spotted from outer space.
Oil and gas companies have recruited powerful allies in the fight, including in California's Central Valley, home to some of the highest concentrations of methane anywhere.
"As federal lands become less cost-effective to produce energy on, this unnecessary rule adds to that burden and could wipe out marginal wells run by family-owned businesses who can't pack up and move their operations," warned a report posted by House Majority Leader Kevin McCarthy of Bakersfield.
He also forecasts financial peril for local governments if the Obama-era rule is not immediately rolled back.
Such pressure has yet to sway many GOP colleagues tangled in the messy politics of methane, such as Colorado Sen. Cory Gardner. His state, like McCarthy's, is among several that have passed their own laws requiring oil and gas companies to pursue aggressive measures to contain the methane. Many of Gardner's constituents, including energy firms subject to the new state law, are demanding he help preserve the federal restraints so operators in adjacent states with no local laws would have to abide by the same rules.
They point to large amounts of air pollution drifting from Utah and New Mexico, exacerbating air problems in Colorado. Local Colorado firms resent that their nearby competitors can ignore leaks they can't. The state's burgeoning clean-energy industry, with its growing bipartisan political might, is applying its own pressure.
"I'm continuing to meet with my constituents on this topic and will continue to do so until the vote," Gardner wrote in an email.
Sens. Susan Collins of Maine and Lindsey Graham of South Carolina, both Republican moderates, announced they would vote against GOP efforts to roll back the rule.
Other Republicans are leaving open the option of joining them, as public concern about leaking methane across the nation puts energy firms under new pressure to invest in technology to contain it.
Charges by energy companies that the rule would bankrupt them conflict with Bureau of Land Management findings that the average small business with an oil or gas operation on federal property would see its profit margin reduced by two-tenths of 1% as a result of the rule.
The amount of methane escaping each year, the Obama administration ultimately concluded, is enough to provide electricity for nearly 740,000 homes. The Government Accountability Office alerted Congress in July that capturing it would boost royalties owed to taxpayers by $23 million.
"We shouldn't just be giving away these taxpayer assets," said Ryan Alexander, president of the advocacy group Taxpayers for Common Sense. "We should be demanding fair compensation for them."
But layered over the fights about royalties and air pollution is the more politically contentious issue of climate change. Methane was a focal point in Obama's expansive, government-wide plan to limit greenhouse gas emissions that President Trump set about tearing up upon taking office.
The White House calls the plan "expensive and unnecessary." This month, Pruitt told oil and gas companies not to bother complying with a directive from the EPA to compile and report data related to their methane emissions, which the agency was to use in crafting new restrictions that would apply to all oil and gas operations, not just those on federal land.
Some Republicans have allied with the charge that methane's role in changing the climate is overhyped, noting the gas escaping from oil and gas operations on federal land accounted for a tiny fraction of 1% of the greenhouse gas that must be cut under the global climate agreement Obama signed in Paris.
But as climate actions go, this one packs a relatively big punch for the price. Methane leaks are America's second-biggest industrial source of climate change, behind power plant emissions, according to the Environmental Defense Fund. Retreating on efforts to contain them is another signal internationally that the U.S. is ceding the leadership role it cemented in Paris to other nations, such as China.
And that doesn't sit well with some Republicans, leaving in limbo a rule rollback that oil and gas companies once anticipated would be easy.
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