March 23 (Reuters) - California's air pollution regulator is due to hold a vote on Thursday on methane emission regulations that it says would be the strictest in the United States in controlling the second-most prevalent greenhouse gas in the atmosphere.
The new standards, proposed by the California Air Resources Board, would tighten efficiency requirements in the production and transportation of natural gas, and also for some oil-handling equipment, and would mandate prompt repair of discovered leaks, said Dave Clegern, a spokesman for the board.
The regulations are expected to pass Thursday's vote by the board, people familiar with the process told Reuters.
In October 2015, the massive Aliso Canyon natural gas leak forced thousands to evacuate in Los Angeles' Porter Ranch area. It took nearly four months to plug and has been estimated to have had a larger climate impact than the 2010 Deepwater Horizon oil spill.
Methane, the main component of commercially distributed natural gas, is produced at dedicated wells and during the extraction of oil. Pound for pound, it traps significantly more heat in the atmosphere than carbon dioxide, the most prevalent greenhouse gas.
Thursday's vote comes shortly after U.S. President Donald Trump proposed major cuts to the Environmental Protection Agency's budget and as the U.S. Senate prepares to vote on repealing a rule limiting methane venting and leaking on federal and tribal lands.
Clegern said the timing of the vote was unintentional and that it followed years of active work on the measure.
“If the federal government won’t protect the people and the environment from oil and gas pollution, it has to be up to the states,” said Tim O’Connor, a director at the Environmental Defense Fund, which worked with the agency on the rule.
Since methane is relatively cheap, economic incentives for producers to fix leaks are small, said Steve Weissman, a lecturer at the Golden School of Public Policy at the University of California at Berkeley who specializes in energy law and policy.
Sabrina Lockhart, a spokeswoman for the California Natural Gas Producers Association, expressed reservations about the proposal on Wednesday, and said industry concerns have centered on requirements for continued inspections even for facilities with strong maintenance records, and the cost of inspection.
If approved, California’s regulations would be the most stringent in the country. Colorado, Wyoming and Ohio have their own regulations to tackle methane, and fracking powerhouse Pennsylvania is in the process of crafting its own rules. (Reporting by Tom James in Seattle; Additional reporting by Valerie Volcovici; Editing by Patrick Enright and Bill Rigby)