U.S. EPA's pollution-cutting oil and gas rule will help cut emissions of a potent greenhouse gas without regulating it directly, say clean air advocates.

EPA released a final rule yesterday that requires new hydraulically fractured gas wells to use technology that will cut toxic substances and smog-forming pollution by 2015. As a co-benefit, the upgrades will also reduce methane -- a greenhouse gas with 30 times the global warming potential of carbon dioxide -- by up to 1.7 million tons, said EPA Assistant Administrator for the Office of Air and Radiation Gina McCarthy.

When it comes to cutting methane emissions from hydraulic fracturing, or fracking, wells, "[EPA] isn't aware of any other technologies that are effective as this rulemaking," McCarthy said.

"The standards are practical, flexible, affordable and achievable," she said.

The New Source Performance Standards will mandate that all new wells install "green" completions, technology that separates gas from liquid hydrocarbons from the flowback of wells to cut pollution. Well operators could also flare, or burn, waste gas instead of releasing it directly into the atmosphere.

But because methane is only a co-benefit, it is not an enforceable requirement, said Stuart Ross, communications director for the Clean Air Task Force.

"We know there's a lot more that can be done for methane," he said.

In the rule, EPA estimates the climate co-benefits -- based on the calculations of the social cost of climate change -- to reach between $100 million to $1.3 billion per year by 2015, when the rule will be fully enforceable. Despite the needed investment to install green completions, industry will benefit from efficiency measures that stop the release of methane -- the basis for natural gas -- which is sold on the market.

"It's a win for the environment, it's a win for the natural gas sector, it's definitely a win for the public," said Jason Schwartz, legal director for the Institute for Policy Integrity at New York University. It is still relatively unclear how to measure the benefits, said Schwartz. Less work has been done on the costs of methane emissions to society.

Exact benefits remain to be measured
Last year, EPA's National Center for Environmental Economics estimated the social cost of a metric ton of methane to be $350 to $2,000. The study calculates the social cost of carbon at $9.40 to $74 per metric ton.

The difference in economic impacts is based on the higher global warming potential of methane but also varies on the time scale of climate effects. Methane stays in the atmosphere for a shorter period of time than carbon dioxide, and its damage to the climate could vary over time.

"We don't know how accurately to translate this number that we've developed for carbon and apply it to methane," said Schwartz. "We don't know how to measure the benefits of averting that."

The Environmental Defense Fund released a study last week that found that methane leakage in hydraulic fracturing and transportation of natural gas has the potential to remove some or all of the benefits of being a low-carbon fuel, compared to coal, gasoline or diesel (E&ENews PM, April 9).

Nevertheless, the attention to methane, in addition to carbon dioxide, is an important one for U.S. climate policy said Paul Bledsoe, senior adviser at the Bipartisan Policy Center.

"It shows that there is an important role for reducing short-lived climate forcers like methane as part of a realistic kind of strategy," Bledsoe said. "It will play in a broader climate strategy."

Benzene and hexane, cancer-causing substances, will drop by 20,000 to 30,000 tons per year. Volatile organic compounds that mix with nitrogen oxides to create smog, will be cut by 190,000 to 290,000 tons per year -- a nearly 95 percent reduction, said EPA's McCarthy.

Approximately 13,000 natural gas wells are fractured or re-fractured each year, said McCarthy. The agency relaxed the final rule from the proposal from last year, allowing well operators an additional two-and-a-half years to comply with the regulation. The proposal stated that operators would need to comply immediately after the rule's publication in the Federal Register (Greenwire, April 18).

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500