SACRAMENTO -- Gov. Jerry Brown has signed the nation's toughest regulation of a controversial oil drilling technique, hydraulic fracturing.
The measure, Brown said in a signing message, "establishes strong environmental protections and transparency requirements for the practice known as "fracking."
At issue is the injection of mixtures of sand, water and chemicals to free oil and natural gas trapped deep underground in shale formations.
The measure originally had widespread support from most environmental groups, but some of them withdrew their endorsements two weeks ago. They argued that the proposal was too weak and did not force drillers to disclose all needed information about chemicals injected into wells.
Oil companies opposed the bill, saying 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 bill's author, Sen. Fran Pavley (D-Agoura Hills), said the legislation, SB 4, is needed because California currently does not regulate fracking and other so-called well-stimulation procedures. Underground water supplies could be at risk in areas where fracking occurs, she said.
The bill also would require state regulators to oversee a related process that uses acid to retrieve hydrocarbons, she said.
The new law requires permitting of wells, notification of neighbors living near drilling and a study of fracking's impact on the environment.
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