A bill that would give California the nation’s toughest regulation of hydraulic fracturing won easy passage on Sept. 11 from the state Legislature, reports The Los Angeles Times.

The bill now goes to Gov. Jerry Brown, who said that he would sign it into law, reports Marc Lifsher in The Times.

Hydraulic fracturing, or “fracking,” is a process that involves injecting mixtures of sand, water and chemicals to free oil and natural gas trapped deep underground in shale formations.

The measure had widespread support from most environmental groups, but some of them withdrew their endorsement just before the Assembly vote, according to the article in The Times, arguing that the proposal was too weak and did not force drillers to disclose all needed information about chemicals injected in wells.

Oil companies opposed the bill, arguing it would make it harder for them to exploit the estimated 15 billion barrels of oil in the Monterey Shale Formation in the southern San Joaquin Valley, the article notes.

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