The U.S. will rein in methane from its biggest human source—the oil and gas industry—but the new rules won't touch a wide swath of places already leaking the invisible, heat-trapping gas.
Strengthened Environmental Protection Agency standards aimed at new energy facilities, proposed Tuesday, will cut somewhere between 20 to 30 percent of the sector's methane emissions from 2012 levels over the next decade, estimates Janet McCabe, acting assistant administrator for the EPA's Office of Air and Radiation.
That's short of the 40 to 45 percent goal the administration announced in January, begging the question, where will the rest be cut from? McCabe declined to give specifics, saying the agency was approaching the target "in a step-wise way" and "not ruling anything out."
Methane, the main component of natural gas, has 25 times the warming potential of carbon dioxide. This latest rule joins the recently finalized Clean Power Plan, which aims to curb carbon dioxide emissions from existing power plants. Both are part of President Barack Obama's pledge to reduce overall U.S. emissions 26 to 28 percent from 2005 levels. (See the Clean Power Plan goals and which states use the most coal power.)
Environmental groups say the U.S. simply can't reach the 45 percent methane reduction goal by focusing mainly on new sources—that it must also target thousands of existing leaky oil and gas facilities.
The U.S. has more than 500 gas processing facilities and an estimated 1.1 million active oil and gas wells. Methane escapes into the atmosphere at points all along the chain between wellhead and end user: Sometimes it's burned off intentionally as a byproduct that comes up along with oil; in other cases it seeps out of old or inefficient pumps, distribution lines, and storage tanks.
The new rule comes on the same day that a paper in Environmental Science and Technology says gathering facilities, where gas is collected from multiple wells, alone are churning out about eight times the methane cited in EPA estimates.
Some companies have been proactive in stopping leaks by installing detection equipment and, for example, performing "green completions" on newly drilled wells, a gas-capturing process that the EPA began requiring in 2012. (Read more about the industry's efforts.)
The American Petroleum Institute said Tuesday's proposed rules are "duplicative, costly, and undermine America’s competitiveness," noting that the industry is already taking action on methane.
But critics say voluntary measures aren't sufficient, and though the EPA estimates the rule will cost up to $420 million, McCabe estimates that it could also save up to $550 million and result in more natural gas going into pipelines as product rather than directly into the air.
EPA says its proposal would also reduce the volatile organic compounds, or VOCs, that contribute to smog. It targets VOCs at certain existing oil and gas facilities in areas that don't meet current ozone standards, which would also result in methane reductions. (See related story: "New U.S. Ozone Rules Likely to Be Felt Nationwide.")
Separately, the Bureau of Land Management is updating its own standards that govern methane leaks from oil and gas production on public land. Still, says the Natural Resources Defense Council, "meaningful progress" on reining in the greenhouse gas "will require an industrywide cleanup—from infrastructure new and old, nationwide," said Meleah Geertsma, a senior attorney with the environmental group. "We are hopeful today’s announcement is just the beginning.”