Methane Leaks
A gas flare is seen at an oil well site outside Williston, North Dakota, July 26, 2013. Andrew Burton/Getty Images

The Senate failed Wednesday to overturn an Obama-era methane restriction, unable to muster a simple majority to repeal the rule when three Republicans who were expected to vote yes instead voted no on the repeal.

Sens. John McCain, R-Ariz., Susan Collins, R-Maine, and Lindsey Graham, R-S.C., voted no on the motion to proceed in repealing the methane restriction rule, bringing the “nay” tally to 51. Lawmakers in the House and Senate have been using the Congressional Review Act to repeal Obama-era rules.

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What is the Congressional Review Act?

The Congressional Review Act was put in place in 1996 to help speed the process by which the legislative branch of the government can repeal restrictions put in place by federal agencies. Each chamber of Congress has 60 days to repeal with a simple majority vote.

Since President Donald J. Trump took office and the congressional term started the Congressional Review Act has been used a number of times to repeal Obama-era regulations. Republicans had been successful in using the CRA 13 times prior to today’s vote, the Washington Post reported.

What is the methane rule?

The methane regulation was a rule, called the Methane and Waste Prevention rule, was issued in November by the U.S. Department of the Interior. It was instituted with the goal of reducing methane emissions released during the natural gas production process on public and Indian land. “The rule updates 30-year-old regulations governing venting, flaring and leaks of natural gas, and will help curb waste of public resources, reduce harmful methane emissions and provide a fair return on public resources for federal taxpayers, tribes and states,” a release from Interior said.

What is methane gas?

Methane is a harmful greenhouse gas that traps far more radiation than carbon dioxide, the Environmental Protection Agency has said. Trapped radiation contributes to global climate change. Methane is produced by farm animals and agriculture, the breakdown of natural materials and human activity. But the processing of natural gas, from extraction to production, transportation, storage and use accounts for the highest percentage of methane pollution. Methane is released when fossil fuels like gas or coal are burned for energy.

The methane rule regulates how much methane could be released during the processing and production of natural gas that takes place on public or Indian land in the hope of reducing the greenhouse gas.

Wednesday’s vote was a surprise for lawmakers and those following the repeal. When McCain cast his vote with a forceful thumbs down, another senator on the floor reacted with a shrug at McCain. A video of the vote and shrug shows McCain then walking off of the Senate floor as the motion to repeal fails.

The Congressional Review Act is only valid for 60 days and expires Thursday, so lawmakers are running out of time to repeal any more Obama-era regulations.